Sample records for inorganic membrane materials

  1. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Jia

    Biorefineries convert biomass into many useful intermediates. For bio-based products to be used for fuel, energy, chemical, and many other applications, water needs to be removed from these aqueous products. Membrane separation technologies can significantly reduce separation energy consumption compared with conventional separation processes such as distillation. Nanoporous inorganic membranes have superior pervaporation performance with excellent organic fouling resistance. However, their commercial applications are limited due to high membrane costs and poor production reproducibility. A novel cost-effective inorganic membrane fabrication technology has been developed with low cost materials and using an advanced membrane fabrication technology. Low cost precursor material formulationmore » was successfully developed with desired material properties for membrane fabrication. An advanced membrane fabrication process was developed using the novel membrane materials to enable the fabrication of separation membranes of various geometries. The structural robustness and separation performance of the low cost inorganic membranes were evaluated. The novel inorganic membranes demonstrated high structural integrity and were effective in pervaporation removal of water.« less

  2. X-ray lithography masking

    NASA Technical Reports Server (NTRS)

    Smith, Henry I. (Inventor); Lim, Michael (Inventor); Carter, James (Inventor); Schattenburg, Mark (Inventor)

    1998-01-01

    X-ray masking apparatus includes a frame having a supporting rim surrounding an x-ray transparent region, a thin membrane of hard inorganic x-ray transparent material attached at its periphery to the supporting rim covering the x-ray transparent region and a layer of x-ray opaque material on the thin membrane inside the x-ray transparent region arranged in a pattern to selectively transmit x-ray energy entering the x-ray transparent region through the membrane to a predetermined image plane separated from the layer by the thin membrane. A method of making the masking apparatus includes depositing back and front layers of hard inorganic x-ray transparent material on front and back surfaces of a substrate, depositing back and front layers of reinforcing material on the back and front layers, respectively, of the hard inorganic x-ray transparent material, removing the material including at least a portion of the substrate and the back layers of an inside region adjacent to the front layer of hard inorganic x-ray transparent material, removing a portion of the front layer of reinforcing material opposite the inside region to expose the surface of the front layer of hard inorganic x-ray transparent material separated from the inside region by the latter front layer, and depositing a layer of x-ray opaque material on the surface of the latter front layer adjacent to the inside region.

  3. Inorganic-based proton conductive composite membranes for elevated temperature and reduced relative humidity PEM fuel cells

    NASA Astrophysics Data System (ADS)

    Wang, Chunmei

    Proton exchange membrane (PEM) fuel cells are regarded as highly promising energy conversion systems for future transportation and stationary power generation and have been under intensive investigations for the last decade. Unfortunately, cutting edge PEM fuel cell design and components still do not allow economically commercial implementation of this technology. The main obstacles are high cost of proton conductive membranes, low-proton conductivity at low relative humidity (RH), and dehydration and degradation of polymer membranes at high temperatures. The objective of this study was to develop a systematic approach to design a high proton conductive composite membrane that can provide a conductivity of approximately 100 mS cm-1 under hot and dry conditions (120°C and 50% RH). The approach was based on fundamental and experimental studies of the proton conductivity of inorganic additives and composite membranes. We synthesized and investigated a variety of organic-inorganic Nafion-based composite membranes. In particular, we analyzed their fundamental properties, which included thermal stability, morphology, the interaction between inorganic network and Nafion clusters, and the effect of inorganic phase on the membrane conductivity. A wide range of inorganic materials was studied in advance in order to select the proton conductive inorganic additives for composite membranes. We developed a conductivity measurement method, with which the proton conductivity characteristics of solid acid materials, zirconium phosphates, sulfated zirconia (S-ZrO2), phosphosilicate gels, and Santa Barbara Amorphous silica (SBA-15) were discussed in detail. Composite membranes containing Nafion and different amounts of functionalized inorganic additives (sulfated inorganics such as S-ZrO2, SBA-15, Mobil Composition of Matter MCM-41, and S-SiO2, and phosphonated inorganic P-SiO2) were synthesized with different methods. We incorporated inorganic particles within Nafion clusters either by mixing inorganic gels or solutions with Nafion solution followed by membrane casting or by blending inorganic powders with Nafion solution. The membrane properties, such as acidity, swelling, water uptake, thermostability, proton conductivity, and electrochemical performance, were explored in depth. We characterized the inorganic phase inside composite membranes and its interaction with the Nafion matrix by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Furthermore, we discussed the effect of these inorganic conductors' properties, such as particle size, conductivity, and interaction between functional groups and the Nafion, on the membrane conductivity. The contribution of hydrophilic inorganic particles in improving the membrane fuel cell performance was numerically analyzed by Tafel plot. Finally, the proton conductivity phenomena in composite membranes were simulated with two proton-transport models; one was based on the rule of mixtures, and the other was described by generalized Stefan-Maxwell equations. In the simulation, we proposed a new route in rational design of high proton-conductive composite membranes.

  4. Molecular sieving silica membrane fabrication process

    DOEpatents

    Raman, Narayan K.; Brinker, Charles Jeffrey

    1998-01-01

    A process for producing a molecular sieve silica membrane comprising depositing a hybrid organic-inorganic polymer comprising at least one organic constituent and at least one inorganic constituent on a porous substrate material and removing at least a portion of the at least one organic constituent of the hybrid organic-inorganic polymer, forming a porous film.

  5. Molecular sieving silica membrane fabrication process

    DOEpatents

    Raman, Narayan K.; Brinker, Charles Jeffrey

    1999-01-01

    A process for producing a molecular sieve silica membrane comprising depositing a hybrid organic-inorganic polymer comprising at least one organic constituent and at least one inorganic constituent on a porous substrate material and removing at least a portion of the at least one organic constituent of the hybrid organic-inorganic polymer, forming a porous film.

  6. Piezoelectric Characteristics of Chiral Polymer Composite Films Obtained under Strong Magnetic Field

    NASA Astrophysics Data System (ADS)

    Nakiri, Takuo; Okuno, Masaki; Maki, Nobuyuki; Kanasaki, Masayoshi; Morimoto, Yu; Okamoto, Satoshi; Ishizuka, Masayuki; Fukuda, Kazuyuki; Takaki, Toshihiko; Tajitsu, Yoshiro

    2005-09-01

    It is difficult to obtain a drawn chiral polymer/inorganic material composite membrane with shear piezoelectricity by the conventional method because the chiral polymer/inorganic material composite membrane breaks during the drawing process by which shear piezoelectricity is realized. Using a strong magnetic field, we propose to manufacture a drawn composite membrane of poly-l-lactic acid (PLLA), a chiral polymer, and hydroxyapatite (Hap), an inoroganic material (PLLA/Hap composite membrane). The manufacturing method used here is effective for obtaining a drawn PLLA/Hap composite membrane with a large uniform area. Also, the shear piezoelectric constant of the drawn PLLA/Hap composite membrane is about 20 pC/N. This value is large for piezoelectric polymers.

  7. Molecular sieving silica membrane fabrication process

    DOEpatents

    Raman, N.K.; Brinker, C.J.

    1999-08-10

    A process is described for producing a molecular sieve silica membrane comprising depositing a hybrid organic-inorganic polymer comprising at least one organic constituent and at least one inorganic constituent on a porous substrate material and removing at least a portion of the at least one organic constituent of the hybrid organic-inorganic polymer, forming a porous film. 11 figs.

  8. Surface modification of polyamide reverse osmosis membrane with organic-inorganic hybrid material for antifouling

    NASA Astrophysics Data System (ADS)

    Zhang, Yang; Wan, Ying; Pan, Guoyuan; Yan, Hao; Yao, Xuerong; Shi, Hongwei; Tang, Yujing; Wei, Xiangrong; Liu, Yiqun

    2018-03-01

    A series of thin-film composite reverse osmosis membranes based on polyamide have been modified by coating the polyvinyl alcohol and 3-mercaptopropyltriethoxysilane aqueous solution prepared by a sol-gel process on the membrane surface, followed by thermal crosslinking treatment. In order to improve the hydrophilicity of the modified TFC membranes, the membranes were then immersed into H2O2 aqueous solution to convert -SH into -SO3H. The resulting TFC membranes were characterized by SEM, AFM, ATR-FTIR, streaming potential, XPS as well as static contact angle. After surface modification with the organic-inorganic hybrid material, the TFC membranes show increased NaCl rejection and decreased water flux with increasing 3-mercaptopropyltrimethoxysilane content in coating solution. The optimal modification membrane (PA-SMPTES-0.8) exhibits a NaCl rejection of 99.29%, higher than that (97.20%) of the virgin PA membrane, and a comparable water flux to virgin PA membrane (41.7 L/m2 h vs 47.9 L/m2 h). More importantly, PA-SMPTES-0.8 membrane shows much more improved fouling resistance to BSA than virgin PA and PVA modified PA (PA-PVA-1.0) membranes. PA-SMPTES-0.8 membrane loses about 13% of the initial flux after BSA fouling for 12 h, which is lower than that of virgin PA and PA-PVA-1.0 membranes (42% and 18%). Furthermore, the flux recovery of PA-SMPTES-0.8 membrane reaches 94% after cleaning. Thus the TFC membranes modified by this organic-inorganic hybrid technology show potential applications as antifouling RO membrane for desalination and purification.

  9. Electrochemical detection of single molecules using abiotic nanopores having electrically tunable dimensions

    DOEpatents

    Sansinena, Jose-Maria [Los Alamos, NM; Redondo, Antonio [Los Alamos, NM; Olazabal, Virginia [Los Alamos, NM; Hoffbauer, Mark A [Los Alamos, NM; Akhadov, Elshan A [Los Alamos, NM

    2009-12-29

    A barrier structure for use in an electrochemical stochastic membrane sensor for single molecule detection. The sensor is based upon inorganic nanopores having electrically tunable dimensions. The inorganic nanopores are formed from inorganic materials and an electrically conductive polymer. Methods of making the barrier structure and sensing single molecules using the barrier structure are also described.

  10. Electrochemical detection of single molecules using abiotic nanopores having electrically tunable dimensions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sansinena, Jose-Maria; Redondo, Antonio; Olazabal, Virginia

    2017-09-12

    A barrier structure for use in an electrochemical stochastic membrane sensor for single molecule detection. The sensor is based upon inorganic nanopores having electrically tunable dimensions. The inorganic nanopores are formed from inorganic materials and an electrically conductive polymer. Methods of making the barrier structure and sensing single molecules using the barrier structure are also described.

  11. Electrochemical detection of single molecules using abiotic nanopores having electrically tunable dimensions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sansinena, Jose-Maria; Redondo, Antonio; Olazabal, Virginia

    2017-07-18

    A barrier structure for use in an electrochemical stochastic membrane sensor for single molecule detection. The sensor is based upon inorganic nanopores having electrically tunable dimensions. The inorganic nanopores are formed from inorganic materials and an electrically conductive polymer. Methods of making the barrier structure and sensing single molecules using the barrier structure are also described.

  12. Electrochemical detection of single molecules using abiotic nanopores having electrically tunable dimensions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sansinena, Jose-Maria; Redondo, Antonio; Olazabal, Virginia

    A barrier structure for use in an electrochemical stochastic membrane sensor for single molecule detection. The sensor is based upon inorganic nanopores having electrically tunable dimensions. The inorganic nanopores are formed from inorganic materials and an electrically conductive polymer. Methods of making the barrier structure and sensing single molecules using the barrier structure are also described.

  13. Inorganic Membranes: Preparation and Application for Water Treatment and Desalination

    PubMed Central

    McKay, Gordon; Buekenhoudt, Anita; Motmans, Filip; Khraisheh, Marwan; Atieh, Muataz

    2018-01-01

    Inorganic membrane science and technology is an attractive field of membrane separation technology, which has been dominated by polymer membranes. Recently, the inorganic membrane has been undergoing rapid development and innovation. Inorganic membranes have the advantage of resisting harsh chemical cleaning, high temperature and wear resistance, high chemical stability, long lifetime, and autoclavable. All of these outstanding properties made inorganic membranes good candidates to be used for water treatment and desalination applications. This paper is a state of the art review on the synthesis, development, and application of different inorganic membranes for water and wastewater treatment. The inorganic membranes reviewed in this paper include liquid membranes, dynamic membranes, various ceramic membranes, carbon based membranes, silica membranes, and zeolite membranes. A brief description of the different synthesis routes for the development of inorganic membranes for application in water industry is given and each synthesis rout is critically reviewed and compared. Thereafter, the recent studies on different application of inorganic membrane and their properties for water treatment and desalination in literature are critically summarized. It was reported that inorganic membranes despite their high synthesis cost, showed very promising results with high flux, full salt rejection, and very low or no fouling. PMID:29304024

  14. Programmable assembly of pressure sensors using pattern-forming bacteria.

    PubMed

    Cao, Yangxiaolu; Feng, Yaying; Ryser, Marc D; Zhu, Kui; Herschlag, Gregory; Cao, Changyong; Marusak, Katherine; Zauscher, Stefan; You, Lingchong

    2017-11-01

    Biological systems can generate microstructured materials that combine organic and inorganic components and possess diverse physical and chemical properties. However, these natural processes in materials fabrication are not readily programmable. Here, we use a synthetic-biology approach to assemble patterned materials. We demonstrate programmable fabrication of three-dimensional (3D) materials by printing engineered self-patterning bacteria on permeable membranes that serve as a structural scaffold. Application of gold nanoparticles to the colonies creates hybrid organic-inorganic dome structures. The dynamics of the dome structures' response to pressure is determined by their geometry (colony size, dome height, and pattern), which is easily modified by varying the properties of the membrane (e.g., pore size and hydrophobicity). We generate resettable pressure sensors that process signals in response to varying pressure intensity and duration.

  15. Inorganic dual-layer microporous supported membranes

    DOEpatents

    Brinker, C. Jeffrey; Tsai, Chung-Yi; Lu, Yungfeng

    2003-03-25

    The present invention provides for a dual-layer inorganic microporous membrane capable of molecular sieving, and methods for production of the membranes. The inorganic microporous supported membrane includes a porous substrate which supports a first inorganic porous membrane having an average pore size of less than about 25 .ANG. and a second inorganic porous membrane coating the first inorganic membrane having an average pore size of less than about 6 .ANG.. The dual-layered membrane is produced by contacting the porous substrate with a surfactant-template polymeric sol, resulting in a surfactant sol coated membrane support. The surfactant sol coated membrane support is dried, producing a surfactant-templated polymer-coated substrate which is calcined to produce an intermediate layer surfactant-templated membrane. The intermediate layer surfactant-templated membrane is then contacted with a second polymeric sol producing a polymeric sol coated substrate which is dried producing an inorganic polymeric coated substrate. The inorganic polymeric coated substrate is then calcined producing an inorganic dual-layered microporous supported membrane in accordance with the present invention.

  16. Hierarchically structured transparent hybrid membranes by in situ growth of mesostructured organosilica in host polymer

    NASA Astrophysics Data System (ADS)

    Vallé, Karine; Belleville, Philippe; Pereira, Franck; Sanchez, Clément

    2006-02-01

    The elaborate performances characterizing natural materials result from functional hierarchical constructions at scales ranging from nanometres to millimetres, each construction allowing the material to fit the physical or chemical demands occurring at these different levels. Hierarchically structured materials start to demonstrate a high input in numerous promising applied domains such as sensors, catalysis, optics, fuel cells, smart biologic and cosmetic vectors. In particular, hierarchical hybrid materials permit the accommodation of a maximum of elementary functions in a small volume, thereby optimizing complementary possibilities and properties between inorganic and organic components. The reported strategies combine sol-gel chemistry, self-assembly routes using templates that tune the material's architecture and texture with the use of larger inorganic, organic or biological templates such as latex, organogelator-derived fibres, nanolithographic techniques or controlled phase separation. We propose an approach to forming transparent hierarchical hybrid functionalized membranes using in situ generation of mesostructured hybrid phases inside a non-porogenic hydrophobic polymeric host matrix. We demonstrate that the control of the multiple affinities existing between organic and inorganic components allows us to design the length-scale partitioning of hybrid nanomaterials with tuned functionalities and desirable size organization from ångström to centimetre. After functionalization of the mesoporous hybrid silica component, the resulting membranes have good ionic conductivity offering interesting perspectives for the design of solid electrolytes, fuel cells and other ion-transport microdevices.

  17. Synthesis and characterization of inorganic materials precipitated into polymeric and novel liquid crystalline systems

    NASA Astrophysics Data System (ADS)

    Lubeck, Christopher Ryan

    The use of nanostructured, hybrid materials possesses great future potential. Many examples of nanostructured materials exist within nature, such as animal bone, animal teeth, and seashells. This research, inspired by nature, strove to mimic salient properties of natural materials, utilizing methods observed within nature to produce materials. Further, this research increased the functionality of the templates from "mere" template to functional participant. Different chemical methods to produce hybrid materials were employed within this research to achieve these goals. First, electro-osmosis was utilized to drive ions into a polymeric matrix to form hybrid inorganic polymer material, creating a material inspired by naturally occurring bone or seashell in which the inorganic component provides strength and the polymeric material decreases the brittleness of the combined hybrid material. Second, self-assembled amphiphiles, forming higher ordered structures, acted as a template for inorganic cadmium sulfide. Electronically active molecules based on ethylene oxide and aniline segments were synthesized to create interaction between the templating material and the resulting inorganic cadmium sulfide. The templating process utilized self-assembly to create the inorganic structure through the interaction of the amphiphiles with water. The use of self-assembly is itself inspired by nature. Self-assembled structures are observed within living cells as cell walls and cell membranes are created through hydrophilic and hydrophobic interactions. Finally, the mesostructured inorganic cadmium sulfide was itself utilized as a template to form mesostructured copper sulfide.

  18. Programmable assembly of pressure sensors using pattern-forming bacteria

    PubMed Central

    Cao, Yangxiaolu; Feng, Yaying; Ryser, Marc D.; Zhu, Kui; Herschlag, Gregory; Cao, Changyong; Marusak, Katherine; Zauscher, Stefan; You, Lingchong

    2017-01-01

    Biological systems can generate microstructured materials that combine organic and inorganic components and possess diverse physical and chemical properties. However, these natural processes in materials fabrication are not readily programmable. Here, we use a synthetic-biology approach to mimic such natural processes to assemble patterned materials.. We demonstrate programmable fabrication of three-dimensional (3D) materials by printing engineered self-patterning bacteria on permeable membranes that serve as a structural scaffold. Application of gold nanoparticles to the colonies creates hybrid organic-inorganic dome structures. The dynamics of the dome structures' response to pressure is determined by their geometry (colony size, dome height and pattern), which is easily modified by varying the properties of the membrane (e.g., pore size and hydrophobicity). We generate resettable pressure sensors that process signals in response to varying pressure intensity and duration. PMID:28991268

  19. Zeolite inorganic scaffolds for novel biomedical application: Effect of physicochemical characteristic of zeolite membranes on cell adhesion and viability

    NASA Astrophysics Data System (ADS)

    Tavolaro, Palmira; Catalano, Silvia; Martino, Guglielmo; Tavolaro, Adalgisa

    2016-09-01

    The design, preparation and selection of inorganic materials useful as functional scaffolds for cell adhesion is a complex question based both on the understanding of the chemical behavior of the materials and individual cells, and on their interactions. Pure zeolite membranes formed from synthetic crystals offer chemically-capable being modulated silanolic surfaces that are amenable to adhesion and growth of fibroblasts. We report the facile preparation of reusable, very longlasting, biocompatible, easily sterilized synthetic scaffolds in a zeolite membrane configuration, which are very stable in aqueous media (apart from ionic strength and pH values), able to adsorb pollutant species and to confine undesired toxic ions (present in culture media). This may ultimately lead to the development of cell supports for economic antibiotic-free culture media.

  20. Superhydrophobic and superhydrophilic surface-enhanced separation performance of porous inorganic membranes for biomass-to-biofuel conversion applications

    DOE PAGES

    Hu, Michael Z.; Engtrakul, Chaiwat; Bischoff, Brian L.; ...

    2016-11-14

    A new class of inorganic-based membranes, i.e., High-Performance Architectured Surface Selective (HiPAS) membranes, is introduced to provide high perm-selective flux by exploiting unique separation mechanisms induced by superhydrophobic or superhydrophilic surface interactions and confined capillary condensation in enlarged membrane pores (~8 nm). The super-hydro-tunable HiPAS membranes were originally developed for the purpose of bio-oil/biofuel processing to achieve selective separations at higher flux relative to size selective porous membranes (e.g., inorganic zeolite-based membranes) and better high-temperature tolerance than polymer membranes (>250 C) for hot vapor processing. Due to surface-enhanced separation selectivity, HiPAS membranes can thus possibly enable larger pores to facilitatemore » large-flux separations by increasing from sub-nanometer pores to mesopores (2-50 nm) for vapor phase or micron-scale pores for liquid phase separations. In this paper, we describe an innovative membrane concept and a materials synthesis strategy to fabricate HiPAS membranes, and demonstrate selective permeation in both vapor- and liquid-phase applications. High permeability and selectivity were demonstrated using surrogate mixtures, such as ethanol-water, toluene-water, and toluene-phenol-water. The overall membrane evaluation results show promise for the future processing of biomass pyrolysis and upgraded product vapors and condensed liquid bio-oil intermediates.« less

  1. Ionogels, ionic liquid based hybrid materials.

    PubMed

    Le Bideau, Jean; Viau, Lydie; Vioux, André

    2011-02-01

    The current interest in ionic liquids (ILs) is motivated by some unique properties, such as negligible vapour pressure, thermal stability and non-flammability, combined with high ionic conductivity and wide electrochemical stability window. However, for material applications, there is a challenging need for immobilizing ILs in solid devices, while keeping their specific properties. In this critical review, ionogels are presented as a new class of hybrid materials, in which the properties of the IL are hybridized with those of another component, which may be organic (low molecular weight gelator, (bio)polymer), inorganic (e.g. carbon nanotubes, silica etc.) or hybrid organic-inorganic (e.g. polymer and inorganic fillers). Actually, ILs act as structuring media during the formation of inorganic ionogels, their intrinsic organization and physicochemical properties influencing the building of the solid host network. Conversely, some effects of confinement can modify some properties of the guest IL, even though liquid-like dynamics and ion mobility are preserved. Ionogels, which keep the main properties of ILs except outflow, while allowing easy shaping, considerably enlarge the array of applications of ILs. Thus, they form a promising family of solid electrolyte membranes, which gives access to all-solid devices, a topical industrial challenge in domains such as lithium batteries, fuel cells and dye-sensitized solar cells. Replacing conventional media, organic solvents in lithium batteries or water in proton-exchange-membrane fuel cells (PEMFC), by low-vapour-pressure and non flammable ILs presents major advantages such as improved safety and a higher operating temperature range. Implementation of ILs in separation techniques, where they benefit from huge advantages as well, relies again on the development of supported IL membranes such as ionogels. Moreover, functionalization of ionogels can be achieved both by incorporation of organic functions in the solid matrix, and by encapsulation of molecular species (from metal complexes to enzymes) in the immobilized IL phase, which opens new routes for designing advanced materials, especially (bio)catalytic membranes, sensors and drug release systems (194 references).

  2. Inorganic Nanoporous Membranes for Immunoisolated Cell-Based Drug Delivery

    PubMed Central

    Mendelsohn, Adam; Desai, Tejal

    2014-01-01

    Materials advances enabled by nanotechnology have brought about promising approaches to improve the encapsulation mechanism for immunoisolated cell-based drug delivery. Cell-based drug delivery is a promising treatment for many diseases but has thus far achieved only limited clinical success. Treatment of insulin dependent diabetes mellitus (IDDM) by transplantation of pancreatic β-cells represents the most anticipated application of cell-based drug delivery technology. This review outlines the challenges involved with maintaining transplanted cell viability and discusses how inorganic nanoporous membranes may be useful in achieving clinical success. PMID:20384222

  3. Novel inorganic materials for polymer electrolyte and alkaline fuel cells

    NASA Astrophysics Data System (ADS)

    Tadanaga, Kiyoharu

    2012-06-01

    Inorganic materials with high ionic conductivity must have big advantages for the thermal and long term stability when the materials are used as the electrolyte of fuel cells. In the present paper, novel ionic conductive inorganic materials for polymer electrolyte fuel cells (PEFCs) and all solid state alkaline fuel cells (AFCs) that have been developed by our group have been reviewed. PEFCs which can operate in temperature range from 100 to 200 °C are intensively studied because of some advantages such as reduction of CO poisoning of Pt catalyst and acceleration of electrode reactions. We showed that the fuel cells using the composite membranes prepared from phosphosilicate gel powder and polyimide precursor can operate in the temperature range from 30 to 180 °C. We also found that the inorganic-organic hybrid membranes with acid-base pairs from 3-aminopropyl triethoxy silane and H2SO4 or H3PO4 show high proton conductivity under dry atmosphere, and the membranes are thermally stable at intermediate temperatures. On the other hand, because the use of noble platinum is the serious problem for the commercialization of PEFCs and because oxidation reactions are usually faster than those of acid-type fuel cells, alkaline type fuel cells, in which a nonplatinum catalyst can be used, are attractive. Recently, we have proposed an alkaline-type direct ethanol fuel cell (DEFC) using a natural clay electrolyte with non-platinum catalysts. So-called hydrotalcite clay, Mg-Al layered double hydroxide intercalated with CO32- (Mg-Al CO32- LDH), has been proved to be a hydroxide ion conductor. An alkalinetype DEFC using Mg-Al CO32- LDH as the electrolyte and aqueous solution of ethanol and potassium hydroxide as a source of fuel exhibited excellent electrochemical performance.

  4. Inorganic Nanoparticles/Metal Organic Framework Hybrid Membrane Reactors for Efficient Photocatalytic Conversion of CO2.

    PubMed

    Maina, James W; Schütz, Jürg A; Grundy, Luke; Des Ligneris, Elise; Yi, Zhifeng; Kong, Lingxue; Pozo-Gonzalo, Cristina; Ionescu, Mihail; Dumée, Ludovic F

    2017-10-11

    Photocatalytic conversion of carbon dioxide (CO 2 ) to useful products has potential to address the adverse environmental impact of global warming. However, most photocatalysts used to date exhibit limited catalytic performance, due to poor CO 2 adsorption capacity, inability to efficiently generate photoexcited electrons, and/or poor transfer of the photogenerated electrons to CO 2 molecules adsorbed on the catalyst surface. The integration of inorganic semiconductor nanoparticles across metal organic framework (MOF) materials has potential to yield new hybrid materials, combining the high CO 2 adsorption capacity of MOF and the ability of the semiconductor nanoparticles to generate photoexcited electrons. Herein, controlled encapsulation of TiO 2 and Cu-TiO 2 nanoparticles within zeolitic imidazolate framework (ZIF-8) membranes was successfully accomplished, using rapid thermal deposition (RTD), and their photocatalytic efficiency toward CO 2 conversion was investigated under UV irradiation. Methanol and carbon monoxide (CO) were found to be the only products of the CO 2 reduction, with yields strongly dependent upon the content and composition of the dopant semiconductor particles. CuTiO 2 nanoparticle doped membranes exhibited the best photocatalytic performance, with 7 μg of the semiconductor nanoparticle enhancing CO yield of the pristine ZIF-8 membrane by 233%, and methanol yield by 70%. This work opens new routes for the fabrication of hybrid membranes containing inorganic nanoparticles and MOFs, with potential application not only in catalysis but also in electrochemical, separation, and sensing applications.

  5. Proton exchange membrane materials for the advancement of direct methanol fuel-cell technology

    DOEpatents

    Cornelius, Christopher J [Albuquerque, NM

    2006-04-04

    A new class of hybrid organic-inorganic materials, and methods of synthesis, that can be used as a proton exchange membrane in a direct methanol fuel cell. In contrast with Nafion.RTM. PEM materials, which have random sulfonation, the new class of materials have ordered sulfonation achieved through self-assembly of alternating polyimide segments of different molecular weights comprising, for example, highly sulfonated hydrophilic PDA-DASA polyimide segment alternating with an unsulfonated hydrophobic 6FDA-DAS polyimide segment. An inorganic phase, e.g., 0.5 5 wt % TEOS, can be incorporated in the sulfonated polyimide copolymer to further improve its properties. The new materials exhibit reduced swelling when exposed to water, increased thermal stability, and decreased O.sub.2 and H.sub.2 gas permeability, while retaining proton conductivities similar to Nafion.RTM.. These improved properties may allow direct methanol fuel cells to operate at higher temperatures and with higher efficiencies due to reduced methanol crossover.

  6. Development of robust fluorinated TiO2/PVDF composite hollow fiber membrane for CO2 capture in gas-liquid membrane contactor

    NASA Astrophysics Data System (ADS)

    Lin, Yuqing; Xu, Yilin; Loh, Chun Heng; Wang, Rong

    2018-04-01

    Gas-liquid membrane contactor (GLMC) is a promising method to attain high efficiency for CO2 capture from flue gas, biogas and natural gas. However, membranes used in GLMC are prone to pore wetting due to insufficient hydrophobicity and low chemical resistance, resulting in significant increase in mass transfer resistance. To mitigate this issue, inorganic-organic fluorinated titania/polyvinylidene fluoride (fTiO2/PVDF) composite hollow fiber (HF) membranes was prepared via facile in-situ vapor induced hydrolyzation method, followed by hydrophobic modification. The proposed composite membranes were expected to couple the superb chemical stability of inorganic and high permeability/low cost of organic materials. The continuous fTiO2 layer deposited on top of PVDF substrate was found to possess a tighter microstructure and better hydrophobicity, which effectively prevented the membrane from wetting and lead to a high CO2 absorption flux (12.7 × 10-3 mol m-2 s-1). In a stability test with 21-day operation of GLMC using 1M monoethanolamine (MEA) as the absorbent, the fTiO2/PVDF membrane remained to be intact with a CO2 absorption flux decline of ∼16%, while the pristine PVDF membrane suffered from a flux decline of ∼80% due to membrane damage. Overall, this work provides an insight into the preparation of high-quality inorganic/organic composite HF membranes for CO2 capture in GLMC application.

  7. Architectured Nanomembranes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sturgeon, Matthew R.; Hu, Michael Z.

    2017-07-01

    This paper has reviewed the frontier field of “architectured membranes” that contains anisotropic oriented porous nanostructures of inorganic materials. Three example types of architectured membranes were discussed with some relevant results from our own research: (1) anodized thin-layer titania membranes on porous anodized aluminum oxide (AAO) substrates of different pore sizes, (2) porous glass membranes on alumina substrate, and (3) guest-host membranes based on infiltration of yttrium-stabilized zirconia inside the pore channels of AAO matrices.

  8. Proton-conducting membranes based on benzimidazole polymers for high-temperature PEM fuel cells. A chemical quest.

    PubMed

    Asensio, Juan Antonio; Sánchez, Eduardo M; Gómez-Romero, Pedro

    2010-08-01

    The development of high-temperature PEM fuel cells (working at 150-200 degrees C) is pursued worldwide in order to solve some of the problems of current cells based on Nafion (CO tolerance, improved kinetics, water management, etc.). Polybenzimidazole membranes nanoimpregnated with phosphoric acid have been studied as electrolytes in PEMFCs for more than a decade. Commercially available polybenzimidazole (PBI) has been the most extensively studied and used for this application in membranes doped with all sorts of strong inorganic acids. In addition to this well-known polymer we also review here studies on ABPBI and other polybenzimidazole type membranes. More recently, several copolymers and related derivatives have attracted many researchers' attention, adding variety to the field. Furthermore, besides phosphoric acid, many other strong inorganic acids, as well as alkaline electrolytes have been used to impregnate benzimidazole membranes and are analyzed here. Finally, we also review different hybrid materials based on polybenzimidazoles and several inorganic proton conductors such as heteropoly acids, as well as sulfonated derivatives of the polymers, all of which contribute to a quickly-developing field with many blooming results and useful potential which are the subject of this critical review (317 references).

  9. Recent advances in the fabrication and structure-specific applications of graphene-based inorganic hybrid membranes.

    PubMed

    Zhao, Xinne; Zhang, Panpan; Chen, Yuting; Su, Zhiqiang; Wei, Gang

    2015-03-12

    The preparation and applications of graphene (G)-based materials are attracting increasing interests due to their unique electronic, optical, magnetic, thermal, and mechanical properties. Compared to G-based hybrid and composite materials, G-based inorganic hybrid membrane (GIHM) offers enormous advantages ascribed to their facile synthesis, planar two-dimensional multilayer structure, high specific surface area, and mechanical stability, as well as their unique optical and mechanical properties. In this review, we report the recent advances in the technical fabrication and structure-specific applications of GIHMs with desirable thickness and compositions. In addition, the advantages and disadvantages of the methods utilized for creating GIHMs are discussed in detail. Finally, the potential applications and key challenges of GIHMs for future technical applications are mentioned.

  10. Advancement in Electrospun Nanofibrous Membranes Modification and Their Application in Water Treatment

    PubMed Central

    Nasreen, Shaik Anwar Ahamed Nabeela; Sundarrajan, Subramanian; Nizar, Syed Abdulrahim Syed; Balamurugan, Ramalingam; Ramakrishna, Seeram

    2013-01-01

    Water, among the most valuable natural resources available on earth, is under serious threat as a result of undesirable human activities: for example, marine dumping, atmospheric deposition, domestic, industrial and agricultural practices. Optimizing current methodologies and developing new and effective techniques to remove contaminants from water is the current focus of interest, in order to renew the available water resources. Materials like nanoparticles, polymers, and simple organic compounds, inorganic clay materials in the form of thin film, membrane or powder have been employed for water treatment. Among these materials, membrane technology plays a vital role in removal of contaminants due to its easy handling and high efficiency. Though many materials are under investigation, nanofibers driven membrane are more valuable and reliable. Synthetic methodologies applied over the modification of membrane and its applications in water treatment have been reviewed in this article. PMID:24957057

  11. Engineering the performance of mixed matrix membranes for gas separations

    NASA Astrophysics Data System (ADS)

    Shu, Shu

    Mixed matrix membranes that comprise domains of organic and inorganic components are investigated in this research. Such materials effectively circumvent the polymeric 'upper bound trade-off curve' and show properties highly attractive for industrial gas separations. Nevertheless, lack of intrinsic compatibility between the organic polymers and inorganic fillers poses the biggest challenge to successful fabrication of mixed matrix membranes. Consequently, control of the nanoscale interface between the sieve and polymer has been the key technical challenge to the implementation of composite membrane materials. The overarching goal of this research was to devise and explore approaches to enhance the performance of mixed matrix membranes by properly tailoring the sieve/polymer interface. In an effort to pursue the aforementioned objective, three approaches were developed and inspected: (i) use of silane coupling agents, (ii) hydrophobizing of sieve surface through alcohol etherification reactions, and (iii) a two-step modification sequence involving the use of a Grignard reagent. A comparison was drawn to evaluate these methodologies and the most effective strategy (Grignard treatment) was selected and further investigated. Successful formulation and characterization of mixed matrix membranes constituting zeolite 4A modified via the Grignard treatment are described in detail. Membranes with impressive improvements in gas separation efficiency and mechanical properties were demonstrated. The basis for the improvements in polymer/sieve compatibility enabled by this specific process were proposed and investigated. A key aspect of the present study was illuminating the detailed chemical mechanisms involved in the Grignard modification. Systematic characterization and carefully designed experiments revealed that the formation of distinctive surface structures is essentially a heterogeneous nucleation process, where Mg(OH)2 crystals grow from the nuclei previously extracted from zeolites. In addition to the main work, discovery of sonication-induced dealumination of zeolites was made during the systematic exploration of Grignard chemistry. The new procedure employing sonication can potentially be applied to prepare zeolites with a variety of Si/Al ratios under relatively mild conditions. The last part of this thesis focused on development of a technique to generalize the highly specific Grignard treatment to inorganic materials other than zeolite 4A. This work delivered composite membranes with improved interfacial adhesion. Moreover, research revealed the effect of surface nuclei density on the ultimate morphology of deposited nanostructures and how different surface morphologies influence polymer/filler interaction in composite membranes. Methods were devised to tailor the morphologies of such structures in order to optimize adhesion enhancement. The acquired results demonstrated the potential of extending this modification process to a broad domain of materials and render it a general methodology for interfacial adhesion promotion.

  12. Challenges and advances in the field of self-assembled membranes.

    PubMed

    van Rijn, Patrick; Tutus, Murat; Kathrein, Christine; Zhu, Leilei; Wessling, Matthias; Schwaneberg, Ulrich; Böker, Alexander

    2013-08-21

    Self-assembled membranes are of vital importance in biological systems e.g. cellular and organelle membranes, however, more focus is being put on synthetic self-assembled membranes not only as an alternative for lipid membranes but also as an alternative for lithographic methods. More investigations move towards self-assembly processes because of the low-cost preparations, structural self-regulation and the ease of creating composite materials and tunable properties. The fabrication of new smart membrane materials via self-assembly is of interest for delivery vessels, size selective separation and purification, controlled-release materials, sensors and catalysts, scaffolds for tissue engineering, low dielectric constant materials for microelectronic devices, antireflective coatings and proton exchange membranes for polymer electrolyte membrane fuel cells. Polymers and nanoparticles offer the most straightforward approaches to create membrane structures. However, alternative approaches using small molecules or composite materials offer novel ultra-thin membranes or multi-functional membranes, respectively. Especially, the composite material membranes are regarded as highly promising since they offer the possibility to combine properties of different systems. The advantages of polymers which provide elastic and flexible yet stable matrices can be combined with nanoparticles being either inorganic, organic or even protein-based which offers pore-size control, catalytic activity or permeation regulation. It is therefore believed that at the interface of different disciplines with each offering different materials or approaches, the most novel and interesting membrane structures are going to be produced. The combinations and approaches presented in this review offer non-conventional self-assembled membrane materials which exhibit a high potential to advance membrane science and find more practical applications.

  13. A review of water recovery by vapour permeation through membranes.

    PubMed

    Bolto, Brian; Hoang, Manh; Xie, Zongli

    2012-02-01

    In vapour permeation the feed is a vapour, not a liquid as in pervaporation. The process employs a polymeric membrane as a semi-permeable barrier between the feed side under high pressure and the permeate side under low pressure. Separation is achieved by the different degrees to which components are dissolved in and diffuse through the membrane, the system working according to a solution-diffusion mechanism. The materials used in the membrane depend upon the types of compounds being separated, so water transport is favoured by hydrophilic material, whether organic or inorganic. The process is used for the dehydration of natural gas and various organic solvents, notably alcohol as biofuel, as well as the removal of water from air and its recovery from waste steam. Waste steam can be found in almost every plant/factory where steam is used. It is frequently contaminated and cannot be reused. Discharging the spent steam to the atmosphere is a serious energy loss and environmental issue. Recycling the steam can significantly improve the overall energy efficiency of an industry, which is responsible for massive CO(2) emissions. Steam separation at high fluxes and temperatures has been accomplished with a composite poly(vinyl alcohol) membrane containing silica nanoparticles, and also, less efficiently, with an inorganic zeolite membrane. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hu, Michael Z.; Engtrakul, Chaiwat; Bischoff, Brian L.

    A new class of inorganic-based membranes, i.e., High-Performance Architectured Surface Selective (HiPAS) membranes, is introduced to provide high perm-selective flux by exploiting unique separation mechanisms induced by superhydrophobic or superhydrophilic surface interactions and confined capillary condensation in enlarged membrane pores (~8 nm). The super-hydro-tunable HiPAS membranes were originally developed for the purpose of bio-oil/biofuel processing to achieve selective separations at higher flux relative to size selective porous membranes (e.g., inorganic zeolite-based membranes) and better high-temperature tolerance than polymer membranes (>250 C) for hot vapor processing. Due to surface-enhanced separation selectivity, HiPAS membranes can thus possibly enable larger pores to facilitatemore » large-flux separations by increasing from sub-nanometer pores to mesopores (2-50 nm) for vapor phase or micron-scale pores for liquid phase separations. In this paper, we describe an innovative membrane concept and a materials synthesis strategy to fabricate HiPAS membranes, and demonstrate selective permeation in both vapor- and liquid-phase applications. High permeability and selectivity were demonstrated using surrogate mixtures, such as ethanol-water, toluene-water, and toluene-phenol-water. The overall membrane evaluation results show promise for the future processing of biomass pyrolysis and upgraded product vapors and condensed liquid bio-oil intermediates.« less

  15. Ion-Conducting Organic/Inorganic Polymers

    NASA Technical Reports Server (NTRS)

    Kinder, James D.; Meador, Mary Ann B.

    2007-01-01

    Ion-conducting polymers that are hybrids of organic and inorganic moieties and that are suitable for forming into solid-electrolyte membranes have been invented in an effort to improve upon the polymeric materials that have been used previously for such membranes. Examples of the prior materials include perfluorosulfonic acid-based formulations, polybenzimidazoles, sulfonated polyetherketone, sulfonated naphthalenic polyimides, and polyethylene oxide (PEO)-based formulations. Relative to the prior materials, the polymers of the present invention offer greater dimensional stability, greater ease of formation into mechanically resilient films, and acceptably high ionic conductivities over wider temperature ranges. Devices in which films made of these ion-conducting organic/inorganic polymers could be used include fuel cells, lithium batteries, chemical sensors, electrochemical capacitors, electrochromic windows and display devices, and analog memory devices. The synthesis of a polymer of this type (see Figure 1) starts with a reaction between an epoxide-functionalized alkoxysilane and a diamine. The product of this reaction is polymerized by hydrolysis and condensation of the alkoxysilane group, producing a molecular network that contains both organic and inorganic (silica) links. The silica in the network contributes to the ionic conductivity and to the desired thermal and mechanical properties. Examples of other diamines that have been used in the reaction sequence of Figure 1 are shown in Figure 2. One can use any of these diamines or any combination of them in proportions chosen to impart desired properties to the finished product. Alternatively or in addition, one could similarly vary the functionality of the alkoxysilane to obtain desired properties. The variety of available alkoxysilanes and diamines thus affords flexibility to optimize the organic/inorganic polymer for a given application.

  16. Asymmetric organic-inorganic hybrid membrane formation via block copolymer-nanoparticle co-assembly.

    PubMed

    Gu, Yibei; Dorin, Rachel M; Wiesner, Ulrich

    2013-01-01

    A facile method for forming asymmetric organic-inorganic hybrid membranes for selective separation applications is developed. This approach combines co-assembly of block copolymer (BCP) and inorganic nanoparticles (NPs) with non-solvent induced phase separation. The method is successfully applied to two distinct molar mass BCPs with different fractions of titanium dioxide (TiO2) NPs. The resulting hybrid membranes exhibit structural asymmetry with a thin nanoporous surface layer on top of a macroporous fingerlike support layer. Key parameters that dictate membrane surface morphology include the fraction of inorganics used and the length of time allowed for surface layer development. The resulting membranes exhibit both good selectivity and high permeability (3200 ± 500 Lm(-2) h(-1) bar(-1)). This fast and straightforward synthesis method for asymmetric hybrid membranes provides a new self-assembly platform upon which multifunctional and high-performance organic-inorganic hybrid membranes can be formed.

  17. Ultra-thin microporous/hybrid materials

    DOEpatents

    Jiang, Ying-Bing [Albuquerque, NM; Cecchi, Joseph L [Albuquerque, NM; Brinker, C Jeffrey [Albuquerque, NM

    2012-05-29

    Ultra-thin hybrid and/or microporous materials and methods for their fabrication are provided. In one embodiment, the exemplary hybrid membranes can be formed including successive surface activation and reaction steps on a porous support that is patterned or non-patterned. The surface activation can be performed using remote plasma exposure to locally activate the exterior surfaces of porous support. Organic/inorganic hybrid precursors such as organometallic silane precursors can be condensed on the locally activated exterior surfaces, whereby ALD reactions can then take place between the condensed hybrid precursors and a reactant. Various embodiments can also include an intermittent replacement of ALD precursors during the membrane formation so as to enhance the hybrid molecular network of the membranes.

  18. Tracking inorganic foulants irreversibly accumulated on low-pressure membranes for treating surface water.

    PubMed

    Yamamura, Hiroshi; Kimura, Katsuki; Higuchi, Kumiko; Watanabe, Yoshimasa; Ding, Qing; Hafuka, Akira

    2015-12-15

    While low-pressure membrane filtration processes (i.e., microfiltration and ultrafiltration) can offer precise filtration than sand filtration, they pose the problem of reduced efficiency due to membrane fouling. Although many studies have examined membrane fouling by organic substances, there is still not enough data available concerning membrane fouling by inorganic substances. The present research investigated changes in the amounts of inorganic components deposited on the surface of membrane filters over time using membrane specimens sampled thirteen times at arbitrary time intervals during pilot testing in order to determine the mechanism by which irreversible fouling by inorganic substances progresses. The experiments showed that the inorganic components that primarily contribute to irreversible fouling vary as filtration continues. It was discovered that, in the initial stage of operation, the main membrane-fouling substance was iron, whereas the primary membrane-fouling substances when operation finished were manganese, calcium, and silica. The amount of iron accumulated on the membrane increased up to the thirtieth day of operation, after which it reached a steady state. After the accumulation of iron became static, subsequent accumulation of manganese was observed. The fact that the removal rates of these inorganic components also increased gradually shows that the size of the exclusion pores of the membrane filter narrows as operation continues. Studying particle size distributions of inorganic components contained in source water revealed that while many iron particles are approximately the same size as membrane pores, the fraction of manganese particles slightly smaller than the pores in diameter was large. From these results, it is surmised that iron particles approximately the same size as the pores block them soon after the start of operation, and as the membrane pores narrow with the development of fouling, they become further blocked by manganese particles approximately the same size as the narrowed pores. Calcium and silica are assumed to accumulate on the membrane due to their cross-linking action and/or complex formation with organic substances such as humic compounds. The present research is the first to clearly show that the inorganic components that contribute to membrane fouling differ according to the stage of membrane fouling progression; the information obtained by this research should enable chemical cleaning or operational control in accordance with the stage of membrane fouling progression. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Ultra-thin Solid-State Li-Ion Electrolyte Membrane Facilitated by a Self-Healing Polymer Matrix.

    PubMed

    Whiteley, Justin M; Taynton, Philip; Zhang, Wei; Lee, Se-Hee

    2015-11-18

    Thin solid membranes are formed by a new strategy, whereby an in situ derived self-healing polymer matrix that penetrates the void space of an inorganic solid is created. The concept is applied as a separator in an all-solid-state battery with an FeS2 -based cathode and achieves tremendous performance for over 200 cycles. Processing in dry conditions represents a paradigm shift for incorporating high active-material mass loadings into mixed-matrix membranes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Hybrid and Mixed Matrix Membranes for Separations from Fermentations

    PubMed Central

    Davey, Christopher John; Leak, David; Patterson, Darrell Alec

    2016-01-01

    Fermentations provide an alternative to fossil fuels for accessing a number of biofuel and chemical products from a variety of renewable and waste substrates. The recovery of these dilute fermentation products from the broth, however, can be incredibly energy intensive as a distillation process is generally involved and creates a barrier to commercialization. Membrane processes can provide a low energy aid/alternative for recovering these dilute fermentation products and reduce production costs. For these types of separations many current polymeric and inorganic membranes suffer from poor selectivity and high cost respectively. This paper reviews work in the production of novel mixed-matrix membranes (MMMs) for fermentative separations and those applicable to these separations. These membranes combine a trade-off of low-cost and processability of polymer membranes with the high selectivity of inorganic membranes. Work within the fields of nanofiltration, reverse osmosis and pervaporation has been discussed. The review shows that MMMs are currently providing some of the most high-performing membranes for these separations, with three areas for improvement identified: Further characterization and optimization of inorganic phase(s), Greater understanding of the compatibility between the polymer and inorganic phase(s), Improved methods for homogeneously dispersing the inorganic phase. PMID:26938567

  1. Comparison of a new inorganic membrane filter (Anopore) with a track-etched polycarbonate membrane filter (Nuclepore) for direct counting of bacteria.

    PubMed Central

    Jones, S E; Ditner, S A; Freeman, C; Whitaker, C J; Lock, M A

    1989-01-01

    Bacterial counts obtained by using a new Anopore inorganic membrane filter were 21 to 33% higher than those obtained by using a Nuclepore polycarbonate membrane filter. In addition, the inorganic filter had higher flow rates, permitting lower vacuum pressures to be used, while the intrinsically flat, rigid surface resulted in easier focusing and sharp definition of bacteria across the whole field of view. Images PMID:2655539

  2. Solid-State NMR Spectroscopy for the Physical Chemistry Laboratory

    ERIC Educational Resources Information Center

    Kinnun, Jacob J.; Leftin, Avigdor; Brown, Michael F.

    2013-01-01

    Solid-state nuclear magnetic resonance (NMR) spectroscopy finds growing application to inorganic and organic materials, biological samples, polymers, proteins, and cellular membranes. However, this technique is often neither included in laboratory curricula nor typically covered in undergraduate courses. On the other hand, spectroscopy and…

  3. Chitosan and alginate types of bio-membrane in fuel cell application: An overview

    NASA Astrophysics Data System (ADS)

    Shaari, N.; Kamarudin, S. K.

    2015-09-01

    The major problems of polymer electrolyte membrane fuel cell technology that need to be highlighted are fuel crossovers (e.g., methanol or hydrogen leaking across fuel cell membranes), CO poisoning, low durability, and high cost. Chitosan and alginate-based biopolymer membranes have recently been used to solve these problems with promising results. Current research in biopolymer membrane materials and systems has focused on the following: 1) the development of novel and efficient biopolymer materials; and 2) increasing the processing capacity of membrane operations. Consequently, chitosan and alginate-based biopolymers seek to enhance fuel cell performance by improving proton conductivity, membrane durability, and reducing fuel crossover and electro-osmotic drag. There are four groups of chitosan-based membranes (categorized according to their reaction and preparation): self-cross-linked and salt-complexed chitosans, chitosan-based polymer blends, chitosan/inorganic filler composites, and chitosan/polymer composites. There are only three alginate-based membranes that have been synthesized for fuel cell application. This work aims to review the state-of-the-art in the growth of chitosan and alginate-based biopolymer membranes for fuel cell applications.

  4. Conductivity Analysis of Membranes for High-Temperature PEMFC Applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reed, R.; Turner, J.A.

    2005-01-01

    Low-temperature operation requirements for per-fluorinated membranes are one factor that limits the viability of current fuel cell technology for transportation and other uses. Because of this, high-temperature membrane materials are being researched. The protonic conductivity of organic/inorganic hybrid composites, Nafion® analog material, and heteropoly acid doped Nafion membranes were studied using a BekkTech® conductivity test cell as a hydrogen pump. The goal was to find a high-temperature membrane with sufficient enough conductive properties to replace the currently implemented low-temperature membranes, such as Nafion. Four-point conductivity measurements were taken using a hydrogen pump experiment. Results showed that one of the organic/inorganicmore » membranes that we tested had similar protonic conductivity to Nafion. Nafion analog membranes were shown to have similar to slightly better conductivity than Nafion at high-temperatures. However, like Nafion, performance dropped upon dehydration of the membrane at higher temperatures. Of the heteropoly acid doped Nafion membranes studied, silicotungstic acid was found to be, overall, the most promising for use as a dopant.« less

  5. The Effect of Surfactant and Compatibilizer on Inorganic Loading and Properties of PPO-based EPMM Membranes

    NASA Astrophysics Data System (ADS)

    Bissadi, Golnaz

    Hybrid membranes represent a promising alternative to the limitations of organic and inorganic materials for high productivity and selectivity gas separation membranes. In this study, the previously developed concept of emulsion-polymerized mixed matrix (EPMM) membranes was further advanced by investigating the effects of surfactant and compatibilizer on inorganic loading in poly(2,6-dimethyl-1,4-phenylene oxide) (PPO)-based EPMM membranes, in which inorganic part of the membranes originated from tetraethylorthosilicate (TEOS). The polymerization of TEOS, which consists of hydrolysis of TEOS and condensation of the hydrolyzed TEOS, was carried out as (i) one- and (ii) two-step processes. In the one-step process, the hydrolysis and condensation take place in the same environment of a weak acid provided by the aqueous solution of aluminum hydroxonitrate and sodium carbonate. In the two-step process, the hydrolysis takes place in the environment of a strong acid (solution of hydrochloric acid), whereas the condensation takes place in weak base environment obtained by adding excess of the ammonium hydroxide solution to the acidic solution of the hydrolyzed TEOS. For both one- and two-step processes, the emulsion polymerization of TEOS was carried out in two types of emulsions made of (i) pure trichloroethylene (TCE) solvent, and (ii) 10 w/v% solution of PPO in TCE, using different combinations of the compatibilizer (ethanol) and the surfactant (n-octanol). The experiments with pure TCE, which are referred to as a gravimetric powder method (GPM) allowed assessing the effect of different experimental parameters on the conversion of TEOS. The GPM tests also provided a guide for the synthesis of casting emulsions containing PPO, from which the EPMM membranes were prepared using a spin coating technique. The synthesized EPMM membranes were characterized using 29Si nuclear magnetic resonance (29Si NMR), differential scanning calorimetry (DSC), inductively coupled plasma mass spectrometry (ICP-MS), and gas permeation measurements carried out in a constant pressure (CP) system. The 29Si NMR analysis verified polymerization of TEOS in the emulsions made of pure TCE, and the PPO solution in TCE. The conversions of TEOS in the two-step process in the two types of emulsions were very close to each other. In the case of the one-step process, the conversions in the TCE emulsion were significantly greater than those in the emulsion of the PPO solution in TCE. Consequently, the conversions of TEOS in the EPMM membranes made in the two-step process were greater than those in the EPMM membranes made in the one-step process. The latter ranged between 10 - 20%, while the highest conversion in the two-step process was 74% in the presence of pure compatibilizer with no surfactant. Despite greater conversions and hence the greater inorganic loadings, the EPMM membranes prepared in the two-step process had glass transition temperatures (Tg) only slightly greater than the reference PPO membranes. In contrast, despite relatively low inorganic loadings, the EPMM membranes prepared in the one-step process had Tgs markedly greater than PPO, and showed the expected trend of an increase in Tg with the inorganic loading. These results indicate that in the case of the one-step process the polymerized TEOS was well integrated with the PPO chains and the interactions between the two phases lead to high Tgs. On the other hand, this was not the case for the EPMM membranes prepared in the two-step process, suggesting possible phase separation between the polymerized TEOS and the organic phase. The latter was confirmed by detecting no selectivity in the EPMM membranes prepared by the two-step process. In contrast, the EPMM membranes prepared in the one-step process in the presence of the compatibilizer and no surfactant showed 50% greater O2 permeability coefficient and a slightly greater O2/N2 permeability ratio compared to the reference PPO membranes.

  6. One-pot biosynthesis of polymer-inorganic nanocomposites

    NASA Astrophysics Data System (ADS)

    Geng, Jiaqing; Yang, Dong; Zhu, Yong; Cao, Lichao; Jiang, Zhongyi; Sun, Yan

    2011-06-01

    A biological method is demonstrated to fabricate the polymer-inorganic nanocomposites (PINCs) utilizing bacterium as an efficient and versatile biofactory. Gluconacetobacter xylinum that can produce bacterial cellulose is incubated in the culture medium containing titanium or silica precursor. The PINCs can be acquired under the elaborate control of the culturing condition of G. xylinum, in which the formation of inorganic nanoparticles about several tens of nanometers in size synchronizes the fabrication of reticulated bacterial cellulose membrane composed of dense and finely branched nanofibers about 60-120 nm in diameter. The composition and chemical states, morphology, thermal stability of the inorganic nanoparticles, and nanocomposites were extensively characterized. A tentative mechanism for the formation of PINCs is proposed. It is hoped that this study may establish a generic platform toward facile and green synthesis of nanocomposite materials.

  7. Progress on Zeolite-membrane-aided Organic Acid Esterification

    NASA Astrophysics Data System (ADS)

    Makertiharta, I. G. B. N.; Dharmawijaya, P. T.

    2017-07-01

    Esterification is a common route to produce carboxylic acid esters as important intermediates in chemical and pharmaceutical industries. However, the reaction is equilibrium limited and needs to be driven forward by selective removal one of the products. There have been some efforts to selectively remove water from reaction mixture via several separation processes (such as pervaporation and reactive distillation). Integrated pervaporation and esterification has gained increasing attention towards. Inorganic zeolite is the most popular material for pervaporation due to its high chemical resistant and separation performance towards water. Zeolite also has proven to be an effective material in removing water from organic compound. Zeolite can act not only as selective layer but also simultaneously act as a catalyst on promoting the reaction. Hence, there are many configurations in integrating zeolite membrane for esterification reaction. As a selective layer to remove water from reaction mixture, high Si/Al zeolite is preferred to enhance its hydrophilicity. However, low Si/Al zeolite is unstable in acid condition due to dealumination thus eliminate its advantages. As a catalyst, acid zeolites (e.g. H-ZSM-5) provide protons for autoprotolysis of the carboxylic acid similar to other catalyst for esterification (e.g. inorganic acid, and ion exchange resins). There are many studies related to zeolite membrane aided esterification. This paper will give brief information related to zeolite membrane role in esterification and also research trend towards it.

  8. Characterizing membrane foulants in MBR with addition of polyferric chloride to enhance phosphorus removal.

    PubMed

    Yang, Xiao-Li; Song, Hai-Liang; Chen, Ming; Cheng, Bing

    2011-10-01

    The effect of polymeric ferric chloride (PFC) addition on phosphorus removal and membrane fouling were investigated in an anoxic/oxic submerged membrane bioreactor. The total phosphorus concentration in effluent averaged at 0.26 mg/L with PFC addition of 10-15 mg/L, while the rate of membrane fouling increased 1.6 times over the control MBR (without PFC addition). Three-dimensional excitation-emission matrix fluorescence spectroscopy and Gel Filtration Chromatography analysis indicated that soluble microbial byproduct-like materials and large molecules (M(W)>100 kDa) were one of the main contributors of biofouling. Fourier transform infrared spectrum confirmed that the major components of the cake layer were proteins and polysaccharides materials. Scanning electron microscopy demonstrated that membrane surfaces were covered with compact gel layer formed by organic substances and Energy Dispersive X-ray analysis indicated that ferric metals were the most important inorganic pollutants. Consequently, soluble organic substances and dose of PFC should be controlled to minimize membrane fouling. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Supported inorganic membranes

    DOEpatents

    Sehgal, Rakesh; Brinker, Charles Jeffrey

    1998-01-01

    Supported inorganic membranes capable of molecular sieving, and methods for their production, are provided. The subject membranes exhibit high flux and high selectivity. The subject membranes are substantially defect free and less than about 100 nm thick. The pores of the subject membranes have an average critical pore radius of less than about 5 .ANG., and have a narrow pore size distribution. The subject membranes are prepared by coating a porous substrate with a polymeric sol, preferably under conditions of low relative pressure of the liquid constituents of the sol. The coated substrate is dried and calcined to produce the subject supported membrane. Also provided are methods of derivatizing the surface of supported inorganic membranes with metal alkoxides. The subject membranes find use in a variety of applications, such as the separation of constituents of gaseous streams, as catalysts and catalyst supports, and the like.

  10. Effects of inorganic substances on water splitting in ion-exchange membranes; II. Optimal contents of inorganic substances in preparing bipolar membranes.

    PubMed

    Kang, Moon-Sung; Choi, Yong-Jin; Moon, Seung-Hyeon

    2004-05-15

    An approach to enhancing the water-splitting performance of bipolar membranes (BPMs) is introducing an inorganic substance at the bipolar (BP) junction. In this study, the immobilization of inorganic matters (i.e., iron hydroxides and silicon compounds) at the BP junction and the optimum concentration have been investigated. To immobilize these inorganic matters, novel methods (i.e., electrodeposition of the iron hydroxide and processing of the sol-gel to introduce silicon groups at the BP junction) were suggested. At optimal concentrations, the immobilized inorganic matters significantly enhanced the water-splitting fluxes, indicating that they provide alternative paths for water dissociation, but on the other hand possibly reduce the polarization of water molecules between the sulfonic acid and quaternary ammonium groups at high contents. Consequently, the amount of inorganic substances introduced should be optimized to obtain the maximum water splitting in the BPM.

  11. Composite polymer membranes for proton exchange membrane fuel cells operating at elevated temperatures and reduced humidities

    NASA Astrophysics Data System (ADS)

    Zhang, Tao

    Proton Exchange Membrane Fuel Cells (PEMFCs) are the leading candidate in the fuel cell technology due to the high power density, solid electrolyte, and low operational temperature. However, PEMFCs operating in the normal temperature range (60-80°C) face problems including poor carbon monoxide tolerance and heat rejection. The poisoning effect can be significantly relieved by operating the fuel cell at elevated temperature, which also improves the heat rejection and electrochemical kinetics. Low relative humidity (RH) operation is also desirable to simplify the reactant humidification system. However, at elevated temperatures, reduced RH PEMFC performance is seriously impaired due to irreversible water loss from presently employed state-of-the-art polymer membrane, Nafion. This thesis focuses on developing polymer electrolyte membranes with high water retention ability for operation in elevated temperature (110-150°C), reduced humidity (˜50%RH) PEMFCs. One approach is to alter Nafion by adding inorganic particles such as TiO2, SiO2, Zr(HPO 4)2, etc. While the presence of these materials in Nafion has proven beneficial, a reduction or no improvement in the PEMFC performance of Nafion/TiO2 and Nafion/Zr(HPO4)2 membranes is observed with reduced particle sizes or increased particle loadings in Nafion. It is concluded that the PEMFC performance enhancement associated with addition of these inorganic particles was not due to the particle hydrophilicity. Rather, the particle, partially located in the hydrophobic region of the membrane, benefits the cell performance by altering the membrane structure. Water transport properties of some Nafion composite membranes were investigated by NMR methods including pulsed field gradient spin echo diffusion, spin-lattice relaxation, and spectral measurements. Compared to unmodified Nafion, composite membranes materials exhibit longer longitudinal relaxation time constant T1. In addition to the Nafion material, sulfonated styrene-ethylene/butylene-styrene triblock copolymer (sSEBS) was investigated as an alternate membrane candidate. sSEBS was modified through introduction of polymer crosslinks using benzephenone as a photoinitiator and addition of a titania co-phase. A photocrosslinked membrane initially containing 15% benzophenone and 3% titania laminated with a 10 mum Nafion layer was found to produce the best PEMFC performance (120°C, 50%RH).

  12. Systems, compositions, and methods for fluid purification

    DOEpatents

    Ho, W.S. Winston; Verweij, Hendrik; Shqau, Krenar; Ramasubranian, Kartik

    2015-12-22

    Disclosed herein are membranes comprising a substrate, a support layer, and a selective layer. In some embodiments the membrane may further comprise a permeable layer. Methods of forming membranes are also disclosed comprising forming a support layer on a substrate, removing adsorbed species from the support layer, preparing a solution containing inorganic materials of a selective layer, contacting the support layer with the solution, drying the membrane, and exposing the membrane to rapid thermal processing. Also disclosed are methods of fluid purification comprising providing a membrane having a feed side and a permeable side, passing a fluid mixture across the feed side of the membrane, providing a driving force for transmembrane permeation, removing from the permeate side a permeate stream enriched in a purified fluid, and withdrawing from the feed side a fluid that is depleted in a purified fluid.

  13. Dynamic hybrid materials for constitutional self-instructed membranes.

    PubMed

    Cazacu, Adinela; Legrand, Yves-Marie; Pasc, Andreea; Nasr, Gihane; Van der Lee, Arie; Mahon, Eugene; Barboiu, Mihail

    2009-05-19

    Constitutional self-instructed membranes were developed and used for mimicking the adaptive structural functionality of natural ion-channel systems. These membranes are based on dynamic hybrid materials in which the functional self-organized macrocycles are reversibly connected with the inorganic silica through hydrophobic noncovalent interactions. Supramolecular columnar ion-channel architectures can be generated by reversible confinement within scaffolding hydrophobic silica mesopores. They can be structurally determined by using X-ray diffraction and morphologically tuned by alkali-salts templating. From the conceptual point of view, these membranes express a synergistic adaptive behavior: the simultaneous binding of the fittest cation and its anion would be a case of "homotropic allosteric interactions," because in time it increases the transport efficiency of the pore-contained superstructures by a selective evolving process toward the fittest ion channel. The hybrid membranes presented here represent dynamic constitutional systems evolving over time to form the fittest ion channels from a library of molecular and supramolecular components, or selecting the fittest ion pairs from a mixture of salts demonstrating flexible adaptation.

  14. Ultem((R))/ZIF-8 mixed matrix hollow fiber membranes for CO2/N-2 separations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dai, Y; Johnson, JR; Karvan, O

    2012-05-15

    Organic-inorganic hybrid (mixed matrix) membranes can potentially extend the separation performance of traditional polymeric materials while maintaining processing convenience. Although many dense films studies have been reported, there have been few reported cases of these materials being successfully extended to asymmetric hollow fibers. In this work we report the first successful production of mixed matrix asymmetric hollow fiber membranes containing metal-organic-framework (MOF) ZIF-8 fillers. Specifically, we have incorporated ZIF-8 into a polyetherimide (Ultem((R)) 1000) matrix and produced dual-layer asymmetric hollow fiber membranes via the dry jet-wet quench method. The outer separating layer of these composite fibers contains 13 wt% (17more » vol%) of ZIF-8 filler. These membranes have been tested over a range of temperatures and pressures for a variety of gas pairs. An increase in separation performance for the CO2/N-2 gas pairs was observed for both pure gas and mixed gas feeds. (C) 2012 Elsevier B.V. All rights reserved.« less

  15. Membrane-based technologies for biogas separations.

    PubMed

    Basu, Subhankar; Khan, Asim L; Cano-Odena, Angels; Liu, Chunqing; Vankelecom, Ivo F J

    2010-02-01

    Over the past two decades, membrane processes have gained a lot of attention for the separation of gases. They have been found to be very suitable for wide scale applications owing to their reasonable cost, good selectivity and easily engineered modules. This critical review primarily focuses on the various aspects of membrane processes related to the separation of biogas, more in specific CO(2) and H(2)S removal from CH(4) and H(2) streams. Considering the limitations of inorganic materials for membranes, the present review will only focus on work done with polymeric materials. An overview on the performance of commercial membranes and lab-made membranes highlighting the problems associated with their applications will be given first. The development studies carried out to enhance the performance of membranes for gas separation will be discussed in the subsequent section. This review has been broadly divided into three sections (i) performance of commercial polymeric membranes (ii) performance of lab-made polymeric membranes and (iii) performance of mixed matrix membranes (MMMs) for gas separations. It will include structural modifications at polymer level, polymer blending, as well as synthesis of mixed matrix membranes, for which addition of silane-coupling agents and selection of suitable fillers will receive special attention. Apart from an overview of the different membrane materials, the study will also highlight the effects of different operating conditions that eventually decide the performance and longevity of membrane applications in gas separations. The discussion will be largely restricted to the studies carried out on polyimide (PI), cellulose acetate (CA), polysulfone (PSf) and polydimethyl siloxane (PDMS) membranes, as these membrane materials have been most widely used for commercial applications. Finally, the most important strategies that would ensure new commercial applications will be discussed (156 references).

  16. Nanoscale patterning controls inorganic-membrane interface structure

    NASA Astrophysics Data System (ADS)

    Almquist, Benjamin D.; Verma, Piyush; Cai, Wei; Melosh, Nicholas A.

    2011-02-01

    The ability to non-destructively integrate inorganic structures into or through biological membranes is essential to realizing full bio-inorganic integration, including arrayed on-chip patch-clamps, drug delivery, and biosensors. Here we explore the role of nanoscale patterning on the strength of biomembrane-inorganic interfaces. AFM measurements show that inorganic probes functionalized with hydrophobic bands with thicknesses complimentary to the hydrophobic lipid bilayer core exhibit strong attachment in the bilayer. As hydrophobic band thickness increases to 2-3 times the bilayer core the interfacial strength decreases, comparable to homogeneously hydrophobic probes. Analytical calculations and molecular dynamics simulations predict a transition between a `fused' interface and a `T-junction' that matches the experimental results, showing lipid disorder and defect formation for thicker bands. These results show that matching biological length scales leads to more intimate bio-inorganic junctions, enabling rational design of non-destructive membrane interfaces.The ability to non-destructively integrate inorganic structures into or through biological membranes is essential to realizing full bio-inorganic integration, including arrayed on-chip patch-clamps, drug delivery, and biosensors. Here we explore the role of nanoscale patterning on the strength of biomembrane-inorganic interfaces. AFM measurements show that inorganic probes functionalized with hydrophobic bands with thicknesses complimentary to the hydrophobic lipid bilayer core exhibit strong attachment in the bilayer. As hydrophobic band thickness increases to 2-3 times the bilayer core the interfacial strength decreases, comparable to homogeneously hydrophobic probes. Analytical calculations and molecular dynamics simulations predict a transition between a `fused' interface and a `T-junction' that matches the experimental results, showing lipid disorder and defect formation for thicker bands. These results show that matching biological length scales leads to more intimate bio-inorganic junctions, enabling rational design of non-destructive membrane interfaces. Electronic supplementary information (ESI) available: Breakthrough rate as a function of force plots for 5 nm, 10 nm and ∞-probes.. See DOI: 10.1039/c0nr00486c

  17. Evaluation of New Reverse Osmosis Membranes for the Separation of Toxic Compounds from Wastewater

    DTIC Science & Technology

    1976-06-01

    limited theoretical work being done regarding the separation of inorganic salts. Glueckauf (1967) has analyzed the repulsive forces between ions and a... inorganic ions by cellulose acetate membrane is in the order of the lyotropic series of ions. However, this criterion of separation has a few...12). The objective of this work was to study the criterion for the separa- tion of inorganic ions with the NS-1O0 membrane. Hopefully, it can be used

  18. Interfacial and transport properties of nanoconstrained inorganic and organic materials

    NASA Astrophysics Data System (ADS)

    Kocherlakota, Lakshmi Suhasini

    Nanoscale constraints impact the material properties of both organic and inorganic systems. The systems specifically studied here are (i) nanoconstrained polymeric systems, poly(l-trimethylsilyl-1-propyne) (PTMSP) and poly(ethylene oxide) (PEO) relevant to gas separation membranes (ii) Zwitterionic polymers poly(sulfobetaine methacrylate)(pSBMA), poly(carboxybetaine acrylamide) (pCBAA), and poly(oligo(ethylene glycol) methyl methacrylate) (PEGMA) brushes critical for reducing bio-fouling (iii) Surface properties of N-layer graphene sheets. Interfacial constraints in ultrathin poly(l-trimethylsilyl-1-propyne) (PTMSP) membranes yielded gas permeabilities and CO2/helium selectivities that exceed bulk PTMSP membrane transport properties by up to three-fold for membranes of submicrometer thickness. Indicative of a free volume increase, a molecular energetic mobility analysis (involving intrinsic friction analysis) revealed enhanced methyl side group mobilities in thin PTMSP membranes with maximum permeation, compared to bulk films. Aging studies conducted over the timescales relevant to the conducted experiments signify that the free volume states in the thin film membranes are highly unstable in the presence of sorbing gases such as CO2. To maintain this high free volume configuration of polymer while improving the temporal stability an "inverse" architecture to conventional polymer nanocomposites was investigated, in which the polymer phase of PTMSP and PEO were interfacially and dimensionally constrained in nanoporous anodic aluminum oxide (AAO) membranes. While with this architecture the benefits of nanocomposite and ultrathin film membranes of PTMSP could be reproduced and improved upon, also the temporal stability could be enhanced substantially. The PEO-AAO nanocomposite membranes also revealed improved gas selectivity properties of CO2 over helium. In the thermal transition studies of zwitterionic pSBMA brushes a reversible critical transition temperature of 60 °C in 27 nm films was evidenced, indicating changes in molecular conformations with respect to the temperature. pCBAA and pEGMA brushes displayed no thermal transitions, suggesting that the molecular conformations of these systems were insensitive to temperature in the investigated regime. The surface energy of a dimensionally constrained inorganic system, graphene is studied via local Hamaker constant determination from a single graphene layer to bulk graphite. Intrinsic friction scattering analysis of dipolar fluctuations of the Van der Waals interactions between an atomic force microscopy tip and graphene layers revealed a four-fold reduction in the surface energy from bulk HOPG to graphene. A numerical analysis based on electron energy loss spectroscopy confirms quantitatively the results.

  19. Nanostructural surface engineering of grafted polymers on inorganic oxide substrates for membrane separations

    NASA Astrophysics Data System (ADS)

    Yoshida, Wayne Hiroshi

    Nanostructural engineering of inorganic substrates by free radical graft polymerization was studied with the goal of developing new membrane materials for pervaporation. Graft polymerization consisted of modification of surface hydroxyls with vinyl trimethoxysilane, followed by solution graft polymerization reaction using either vinyl acetate (VAc) or vinyl pyrrolidone (VP). The topology of the modified surfaces was studied by atomic force microscopy (AFM) on both atomically smooth silicon wafer substrates and microporous inorganic membrane supports in order to deduce the effects of modification on the nanostructural properties of the membrane. While unmodified wafers showed a root-mean-square (RMS) surface roughness of 0.21 +/- 0.03 nm, roughness increased to 3.15 +/- 0.23 nm upon silylation. Under poor solvent conditions (i.e., air), surfaces modified with higher poly(vinyl acetate) (PVAc) or poly(vinyl pyrrolidone) (PVP) polymer graft yields displayed lateral inhomogeneities in the polymer layer. Although RMS surface roughness was nearly identical (0.81--0.85 nm) for PVAc-modified surfaces grafted at different monomer concentrations, the skewness of the height distribution decreased from 2.22 to 0.78 as polymer graft yield increased from 0.8 to 3.5 mg/m2. The polymer-modified surfaces were used to create inorganic pervaporation membranes consisting of a single macromolecular separation layer formed by graft polymerization. PVAc grafted silica membranes (500A native pore size) were found selective for MTBE in the separation of 0.1--1% (v/v) MTBE from water, achieving MTBE enrichment factors as high as 371 at a permeate flux of 0.38 l/m2 hr and a Reynolds number of 6390; however, these membranes could not separate anhydrous organic mixtures. Pervaporative separation of methanol/MTBE mixtures was possible with PVAc and PVP-modified alumina supports of 50A native pore size, where the separation layer consisted of grafted polymer chains with estimated radius of gyration 4.5--6.8 times larger than the membrane pore radius. Methanol separation factors for the PVP and PVAc-grafted alumina pervaporation membranes reached values of 26 and 100 (respectively) at total permeate fluxes of 0.055--1.26 kg/m 2 hr and 0.55--6.19 kg/m2 hr. The present study demonstrated that selective pervaporation membranes for separation of both organic/organic and organic/aqueous mixtures can be effectively designed by careful selection of the surface-grafted polymer chain density and the ratio of the polymer chain size to the native support pore size.

  20. Controllable synthesis of single-walled carbon nanotube framework membranes and capsules.

    PubMed

    Song, Changsik; Kwon, Taeyun; Han, Jae-Hee; Shandell, Mia; Strano, Michael S

    2009-12-01

    Controlling the morphology of membrane components at the nanometer scale is central to many next-generation technologies in water purification, gas separation, fuel cell, and nanofiltration applications. Toward this end, we report the covalent assembly of single-walled carbon nanotubes (SWNTs) into three-dimensional framework materials with intertube pores controllable by adjusting the size of organic linker molecules. The frameworks are fashioned into multilayer membranes possessing linker spacings from 1.7 to 3.0 nm, and the resulting framework films were characterized, including transport properties. Nanoindentation measurements by atomic force microscopy show that the spring constant of the SWNT framework film (22.6 +/- 1.2 N/m) increased by a factor of 2 from the control value (10.4 +/- 0.1 N/m). The flux ratio comparison in a membrane-permeation experiment showed that larger spacer sizes resulted in larger pore structures. This synthetic method was equally efficient on silica microspheres, which could then be etched to create all-SWNT framework, hollow capsules approximately 5 mum in diameter. These hollow capsules are permeable to organic and inorganic reagents, allowing one to form inorganic nanoparticles, for example, that become entrapped within the capsule. The ability to encapsulate functional nanomaterials inside perm-selective SWNT cages and membranes may find applications in new adsorbents, novel catalysts, and drug delivery vehicles.

  1. [Analysis and separation of organic and inorganic speciations of soluble zinc in edible flowers].

    PubMed

    Peng, Shan-shan; Huang, Guo-qing

    2005-02-01

    Considering the medicinal effects of the edible flowers, the authors studied the separation of trace element zinc's soluble organic and inorganic speciations in water decoction of three edible flowers: Chrysanthemum, Cottonrose hibiscus and Honeysucker by using the 0.45 microm membrane filter and amberlite XAD-2 macroreticular resins. And trace element zinc contents were determined by atomic absorption spectrometry. The optimal conditions for separation had been established. This study verifies the economic value of developing edible flowers, and provides theoretical basis for developing edible flowers as the third functional food materials.

  2. Reduction in excess sludge production in a dairy wastewater treatment plant via nozzle-cavitation treatment: case study of an on-farm wastewater treatment plant.

    PubMed

    Hirooka, Kayako; Asano, Ryoki; Yokoyama, Atsushi; Okazaki, Masao; Sakamoto, Akira; Nakai, Yutaka

    2009-06-01

    Nozzle-cavitation treatment was used to reduce excess sludge production in a dairy wastewater treatment plant. During the 450-d pilot-scale membrane bioreactor (MBR) operation, when 300 l of the sludge mixed liquor (1/10 of the MBR volume) was disintegrated per day by the nozzle-cavitation treatment with the addition of sodium hydrate (final concentration: 0.01% W/W) and returned to the MBR, the amount of excess sludge produced was reduced by 80% compared with that when sludge was not disintegrated. On the basis of the efficiency of CODCr removal and the ammonia oxidation reaction, it was concluded that the nozzle-cavitation treatment did not have a negative impact on the performance of the MBR. The estimation of the inorganic material balance showed that when the mass of the excess sludge was decreased, the inorganic content of the activated sludge increased and some part of the inorganic material was simultaneously solubilized in the effluent.

  3. Three-Dimensionally Printed Microfluidic Cross-flow System for Ultrafiltration/Nanofiltration Membrane Performance Testing.

    PubMed

    Wardrip, Nathaniel C; Arnusch, Christopher J

    2016-02-13

    Minimization and management of membrane fouling is a formidable challenge in diverse industrial processes and other practices that utilize membrane technology. Understanding the fouling process could lead to optimization and higher efficiency of membrane based filtration. Here we show the design and fabrication of an automated three-dimensionally (3-D) printed microfluidic cross-flow filtration system that can test up to 4 membranes in parallel. The microfluidic cells were printed using multi-material photopolymer 3-D printing technology, which used a transparent hard polymer for the microfluidic cell body and incorporated a thin rubber-like polymer layer, which prevents leakages during operation. The performance of ultrafiltration (UF), and nanofiltration (NF) membranes were tested and membrane fouling could be observed with a model foulant bovine serum albumin (BSA). Feed solutions containing BSA showed flux decline of the membrane. This protocol may be extended to measure fouling or biofouling with many other organic, inorganic or microbial containing solutions. The microfluidic design is especially advantageous for testing materials that are costly or only available in small quantities, for example polysaccharides, proteins, or lipids due to the small surface area of the membrane being tested. This modular system may also be easily expanded for high throughput testing of membranes.

  4. Three-Dimensionally Printed Microfluidic Cross-flow System for Ultrafiltration/Nanofiltration Membrane Performance Testing

    PubMed Central

    Wardrip, Nathaniel C.; Arnusch, Christopher J.

    2016-01-01

    Minimization and management of membrane fouling is a formidable challenge in diverse industrial processes and other practices that utilize membrane technology. Understanding the fouling process could lead to optimization and higher efficiency of membrane based filtration. Here we show the design and fabrication of an automated three-dimensionally (3-D) printed microfluidic cross-flow filtration system that can test up to 4 membranes in parallel. The microfluidic cells were printed using multi-material photopolymer 3-D printing technology, which used a transparent hard polymer for the microfluidic cell body and incorporated a thin rubber-like polymer layer, which prevents leakages during operation. The performance of ultrafiltration (UF), and nanofiltration (NF) membranes were tested and membrane fouling could be observed with a model foulant bovine serum albumin (BSA). Feed solutions containing BSA showed flux decline of the membrane. This protocol may be extended to measure fouling or biofouling with many other organic, inorganic or microbial containing solutions. The microfluidic design is especially advantageous for testing materials that are costly or only available in small quantities, for example polysaccharides, proteins, or lipids due to the small surface area of the membrane being tested. This modular system may also be easily expanded for high throughput testing of membranes.  PMID:26968008

  5. Recent progress on exploring exceptionally high and anisotropic H+/OH– ion conduction in two-dimensional materials

    PubMed Central

    Sun, Pengzhan; Sasaki, Takayoshi

    2017-01-01

    Ion conducting membranes/electrolytes have been employed extensively in some important industrial and biological systems, especially in fuel cells, water electrolyzers, gas separation, sensors and biological selective ion transport, acting as one of the core components and sometimes directly determining the device performance. However, the traditional polymeric proton exchange membranes (PEMs)/anion exchange membranes (AEMs) suffer from highly toxic preparation procedures, poor thermal and chemical stabilities, and unsatisfactory ion conductivities. This has triggered researchers worldwide to explore alternative inorganic building blocks with high ion conductivities and stabilities from the new materials library, hoping to solve the above long-lasting problems. The recent burgeoning research on two-dimensional (2D) materials has unveiled exceptionally high ionic conductivities, which raises the feasibility of fabricating high-performance nanosheet-based ion conductors/membranes. In this perspective, the recent advances in measuring and understanding the exceptionally high and anisotropic H+/OH– ion conductivities of representative 2D materials, e.g. graphene oxide (GO), vermiculite and layered double hydroxide (LDH) nanosheets, are reviewed. In particular, regarding the anisotropic ionic conduction in 2D nanosheets, possible design strategies and technological innovations for fabricating macroscopic nanosheet-based ionic conductors/membranes are proposed for maximizing the high in-plane conduction, which may serve to guide future development of high-performance industrial and biological systems relying on H+/OH– conducting membranes. PMID:29629071

  6. Recent progress on exploring exceptionally high and anisotropic H+/OH- ion conduction in two-dimensional materials.

    PubMed

    Sun, Pengzhan; Ma, Renzhi; Sasaki, Takayoshi

    2018-01-07

    Ion conducting membranes/electrolytes have been employed extensively in some important industrial and biological systems, especially in fuel cells, water electrolyzers, gas separation, sensors and biological selective ion transport, acting as one of the core components and sometimes directly determining the device performance. However, the traditional polymeric proton exchange membranes (PEMs)/anion exchange membranes (AEMs) suffer from highly toxic preparation procedures, poor thermal and chemical stabilities, and unsatisfactory ion conductivities. This has triggered researchers worldwide to explore alternative inorganic building blocks with high ion conductivities and stabilities from the new materials library, hoping to solve the above long-lasting problems. The recent burgeoning research on two-dimensional (2D) materials has unveiled exceptionally high ionic conductivities, which raises the feasibility of fabricating high-performance nanosheet-based ion conductors/membranes. In this perspective, the recent advances in measuring and understanding the exceptionally high and anisotropic H + /OH - ion conductivities of representative 2D materials, e.g. graphene oxide (GO), vermiculite and layered double hydroxide (LDH) nanosheets, are reviewed. In particular, regarding the anisotropic ionic conduction in 2D nanosheets, possible design strategies and technological innovations for fabricating macroscopic nanosheet-based ionic conductors/membranes are proposed for maximizing the high in-plane conduction, which may serve to guide future development of high-performance industrial and biological systems relying on H + /OH - conducting membranes.

  7. Membrane bioreactors for treating waste streams.

    PubMed

    Howell, J A; Arnot, T C; Liu, W

    2003-03-01

    Membrane bioreactors (MBRs) have a number of advantages for treating wastewater containing large quantities of BOD. This paper reviews the inherent advantages of an MBR, which include high potential biomass loadings, lower sludge yields, and retention of specialized organisms that may not settle well in clarifiers. A major problem in effluent treatment occurs when mixed inorganic and organic wastes occur with high concentrations of pollutants. Inorganics that might cause extremes of pH and/or salinity will inhibit microbial growth and only specialized organisms can survive under these conditions. Refractory organics are only biodegraded with difficulty by specialized organisms, which usually do not resist the extreme inorganic environments. The use of membrane bioreactors to help separate the micro-organisms from the inorganic compounds, yet permit the organics to permeate, has been developed in two different designs that are outlined in this paper. The use of membrane contactors in a multimembrane stripping system to treat acidic chlorinated wastes is proposed and discussed.

  8. The "Origin-of-Life Reactor" and Reduction of CO2 by H2 in Inorganic Precipitates.

    PubMed

    Jackson, J Baz

    2017-08-01

    It has been suggested that inorganic membranes were forerunners of organic membranes at the origin of life. Such membranes, interposed between alkaline fluid in submarine vents and the more acidic Hadean ocean, were thought to house inorganic molecular machines. H + flowed down the pH gradient (ΔpH) from ocean to vent through the molecular machines to drive metabolic reactions for early life. A set of experiments was performed by Herschy et al. (J Mol Evol 79:213-227, 2014) who followed earlier work to construct inorganic precipitate membranes which, they argued, would be transected by a ΔpH. They supposed that inorganic molecular machines might assemble by chance in the precipitate membranes, and be capable of using the ΔpH to drive unfavourable reduction of CO 2 by H 2 to formate and formaldehyde. Indeed, these workers detected both of these compounds in their origin-of-life reaction vessel and contend this was proof of principle for their hypothesis. However, it is shown here by a straightforward calculation that the formate produced was only that which reached on approach to equilibrium without any driving force from ΔpH. We conclude that the reaction was facilitated by isotropic catalysts in the precipitate membrane but not by an anisotropic ΔpH-driven molecular machine.

  9. Synthesis and Characterization of Organic-Inorganic Nanocomposite Poly-o-anisidine Sn(IV) Arsenophosphate: Its Analytical Applications as Pb(II) Ion-Selective Membrane Electrode

    PubMed Central

    Khan, Asif Ali; Habiba, Umme; Khan, Anish

    2009-01-01

    Poly-o-anisidine Sn(IV) arsenophosphate is a newly synthesized nanocomposite material and has been characterized on the basis of its chemical composition, ion exchange capacity, TGA-DTA, FTIR, X-RAY, SEM, and TEM studies. On the basis of distribution studies, the exchanger was found to be highly selective for lead that is an environmental pollutant. For the detection of lead in water a heterogeneous precipitate based ion-selective membrane electrode was developed by means of this composite cation exchanger as electroactive material. The membrane electrode is mechanically stable, with a quick response time, and can be operated over a wide pH range. The selectivity coefficients were determined by mixed solution method and revealed that the electrode is sensitive for Pb(II) in presence of interfering cations. The practical utility of this membrane electrode has been established by employing it as an indicator electrode in the potentiometric titration of Pb(II). PMID:20140082

  10. Removal of precursors and disinfection by-products (DBPs) by membrane filtration from water; a review.

    PubMed

    Zazouli, Mohammad Ali; Kalankesh, Laleh R

    2017-01-01

    Disinfection by-products (DBPs) have heterogeneous structures which are suspected carcinogens as a result of reactions between NOMs (Natural Organic Matter) and oxidants/disinfectants such as chlorine. Because of variability in DBPs characteristics, eliminate completely from drinking water by single technique is impossible. The current article reviews removal of the precursors and DBPs by different membrane filtration methods such as Microfiltration (MF), Ultrafiltration (UF), Nanofiltration (NF) and Reverse Osmosis (RO) techniques. Also, we provide an overview of existing and potentially Membrane filtration techniques, highlight their strengths and drawbacks. MF membranes are a suitable alternative to remove suspended solids and colloidal materials. However, NOMs fractions are effectively removed by negatively charged UF membrane. RO can remove both organic and inorganic DBPs and precursors simultaneously. NF can be used to remove compounds from macromolecular size to multivalent ions.

  11. Template directed synthesis of plasmonic gold nanotubes with tunable IR absorbance.

    PubMed

    Bridges, Colin R; Schon, Tyler B; DiCarmine, Paul M; Seferos, Dwight S

    2013-04-01

    A nearly parallel array of pores can be produced by anodizing aluminum foils in acidic environments. Applications of anodic aluminum oxide (AAO) membranes have been under development since the 1990's and have become a common method to template the synthesis of high aspect ratio nanostructures, mostly by electrochemical growth or pore-wetting. Recently, these membranes have become commercially available in a wide range of pore sizes and densities, leading to an extensive library of functional nanostructures being synthesized from AAO membranes. These include composite nanorods, nanowires and nanotubes made of metals, inorganic materials or polymers. Nanoporous membranes have been used to synthesize nanoparticle and nanotube arrays that perform well as refractive index sensors, plasmonic biosensors, or surface enhanced Raman spectroscopy (SERS) substrates, as well as a wide range of other fields such as photo-thermal heating, permselective transport, catalysis, microfluidics, and electrochemical sensing. Here, we report a novel procedure to prepare gold nanotubes in AAO membranes. Hollow nanostructures have potential application in plasmonic and SERS sensing, and we anticipate these gold nanotubes will allow for high sensitivity and strong plasmon signals, arising from decreased material dampening.

  12. Dynamic hybrid materials for constitutional self-instructed membranes

    PubMed Central

    Cazacu, Adinela; Legrand, Yves-Marie; Pasc, Andreea; Nasr, Gihane; Van der Lee, Arie; Mahon, Eugene; Barboiu, Mihail

    2009-01-01

    Constitutional self-instructed membranes were developed and used for mimicking the adaptive structural functionality of natural ion-channel systems. These membranes are based on dynamic hybrid materials in which the functional self-organized macrocycles are reversibly connected with the inorganic silica through hydrophobic noncovalent interactions. Supramolecular columnar ion-channel architectures can be generated by reversible confinement within scaffolding hydrophobic silica mesopores. They can be structurally determined by using X-ray diffraction and morphologically tuned by alkali-salts templating. From the conceptual point of view, these membranes express a synergistic adaptive behavior: the simultaneous binding of the fittest cation and its anion would be a case of “homotropic allosteric interactions,” because in time it increases the transport efficiency of the pore-contained superstructures by a selective evolving process toward the fittest ion channel. The hybrid membranes presented here represent dynamic constitutional systems evolving over time to form the fittest ion channels from a library of molecular and supramolecular components, or selecting the fittest ion pairs from a mixture of salts demonstrating flexible adaptation. PMID:19416909

  13. Hydrogen Selective Inorganic membranes for Gas Separations under High Pressure Intermediate Temperature Hydrocarbonic Envrionment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rich Ciora; Paul KT Liu

    2012-06-27

    In this project, we have successfully developed a full scale commercially ready carbon molecular sieve (CMS) based membrane for applications in H{sub 2} recovery from refinery waste and other aggressive gas streams. Field tests at a refinery pilot plant and a coal gasification facility have successfully demonstrated its ability to recovery hydrogen from hydrotreating and raw syngas respectively. High purity H{sub 2} and excellent stability of the membrane permeance and selectivity were obtained in testing conducted over >500 hours at each site. The results from these field tests as well as laboratory testing conclude that the membranes can be operated at high pressures (up to 1,000 psig) and temperatures (up to 300 C) in presence of aggressive contaminants, such as sulfur and nitrogen containing species (H{sub 2}S, CO{sub 2}, NH{sub 3}, etc), condensable hydrocarbons, tar-like species, heavy metals, etc. with no observable effect on membrane performance. By comparison, similar operating conditions and/or environments would rapidly destroy competing membranes, such as polymeric, palladium, zeolitic, etc. Significant cost savings can be achieved through recovering H{sub 2} from refinery waste gas using this newly developed CMS membrane. Annual savings ofmore » $$2 to 4MM/year (per 20,000 scfd of waste gas) can be realized by recovering the H{sub 2} for reuse (versus fuel). Projecting these values over the entire US market, potential H{sub 2} savings from refinery waste gases on the order of 750 to 1,000MM scfd and $$750 to $1,000MM per year are possible. In addition to the cost savings, potential energy savings are projected to be ca. 150 to 220 tBTU/yr and CO{sub 2} gas emission reductions are projected to be ca. 5,000 to 6,500MMtons/year. The full scale membrane bundle developed as part of this project, i.e., 85 x 30 inch ceramic membrane tubes packaged into a full ceramic potting, is an important accomplishment. No comparable commercial scale product exists in the inorganic membrane field. Further, this newly developed full scale bundle concept can be extended to other thin film inorganic membrane technology (Pd, zeolite, etc), providing a potential commercialization pathway for these membrane materials that demonstrate high potential in a variety of separation applications yet remain a laboratory 'novelty' for lack of a full scale support. Overall, the project has been highly successful and all of the project objectives have been met. We have developed the first of its kind commercial scale carbon molecular sieve membrane and demonstrated its performance in field testing under aggressive operating conditions and in the presence of chemical contaminants that would rapidly destroy alternative organic and inorganic membranes. This innovative membrane permits H{sub 2} recovery from gas streams that up until now have not been successfully treated with membrane or conventional technology. Our end user participant is currently pursuing the field demonstration of this membrane for hydrogen recovery at its refinery site.« less

  14. Hydrophobization of track membrane surface by ion-plasma sputtering method

    NASA Astrophysics Data System (ADS)

    Kuklin, I. E.; Khlebnikov, N. A.; Barashev, N. R.; Serkov, K. V.; Polyakov, E. V.; Zdorovets, M. V.; Borgekov, D. B.; Zhidkov, I. S.; Cholakh, S. O.; Kozlovskiy, A. L.

    2017-09-01

    This article reviews the possibility of applying inorganic coatings of metal compounds on PTM by ion-plasma sputtering. The main aim of this research is to increase the contact angle of PTM surfaces and to impart the properties of a hydrophobic material to it. After the modification, the initial contact angle increased from 70° to 120°.

  15. Evaluation of the Snap Sampler for Sampling Ground Water Monitoring Wells for Inorganic Analytes

    DTIC Science & Technology

    2008-12-01

    08-25 3 Accumulation samplers rely on both diffusion through a membrane and then sorption by some type of sorbent material that is contained in the...the materials in the sampler to equilibrate with the analytes in the well water thereby prevent- ing losses of analytes due to sorption by the sampler...The spring in the bottles is coated with perfluoroalkoxy ( PFA ) (Teflon) and is connected to PFA end caps at both ends of the bottle. Currently

  16. SOLVENT NANOFILTRATION USING LOW-COST INORGANIC MEMBRANE MODULES - PHASE I

    EPA Science Inventory

    This Phase I project addresses: (1) development of fully inorganic nanofiltration (NF) membrane modules that have the attributes of low-cost, excellent chemical resistance in aggressive organic and aqueous media and high thermal stability; and (2) demonstration of the perfo...

  17. Biomimetic Hybridization of Kevlar into Silk Fibroin: Nanofibrous Strategy for Improved Mechanic Properties of Flexible Composites and Filtration Membranes.

    PubMed

    Lv, Lili; Han, Xiangsheng; Zong, Lu; Li, Mingjie; You, Jun; Wu, Xiaochen; Li, Chaoxu

    2017-08-22

    Silk, one of the strongest natural biopolymers, was hybridized with Kevlar, one of the strongest synthetic polymers, through a biomimetic nanofibrous strategy. Regenerated silk materials have outstanding properties in transparency, biocompatibility, biodegradability and sustainability, and promising applications as diverse as in pharmaceutics, electronics, photonic devices and membranes. To compete with super mechanic properties of their natural counterpart, regenerated silk materials have been hybridized with inorganic fillers such as graphene and carbon nanotubes, but frequently lose essential mechanic flexibility. Inspired by the nanofibrous strategy of natural biomaterials (e.g., silk fibers, hemp and byssal threads of mussels) for fantastic mechanic properties, Kevlar was integrated in regenerated silk materials by combining nanometric fibrillation with proper hydrothermal treatments. The resultant hybrid films showed an ultimate stress and Young's modulus two times as high as those of pure regenerated SF films. This is not only because of the reinforcing effect of Kevlar nanofibrils, but also because of the increasing content of silk β-sheets. When introducing Kevlar nanofibrils into the membranes of silk nanofibrils assembled by regenerated silk fibroin, the improved mechanic properties further enabled potential applications as pressure-driven nanofiltration membranes and flexible substrates of electronic devices.

  18. Ultrafast excited state deactivation of doped porous anodic alumina membranes

    NASA Astrophysics Data System (ADS)

    Makhal, Abhinandan; Sarkar, Soumik; Pal, Samir Kumar; Yan, Hongdan; Wulferding, Dirk; Cetin, Fatih; Lemmens, Peter

    2012-08-01

    Free-standing, bi-directionally permeable and ultra-thin anodic aluminum oxide (AAO) membranes establish attractive templates (host) for the synthesis of nano-dots and rods of various materials (guest). This is due to their chemical and structural integrity and high periodicity on length scales of 5-150 nm which are often used to host photoactive nano-materials for various device applications including dye-sensitized solar cells. In the present study, AAO membranes are synthesized by using electrochemical methods and a detailed structural characterization using FEG-SEM, XRD and TGA confirms the porosity and purity of the material. Defect-mediated photoluminescence quenching of the porous AAO membrane in the presence of an electron accepting guest organic molecule (benzoquinone) is studied by means of steady-state and picosecond/femtosecond-resolved luminescence measurements. Using time-resolved luminescence transients, we have also revealed light harvesting of complexes of porous alumina impregnated with inorganic quantum dots (Maple Red) or gold nanowires. Both the Förster resonance energy transfer and the nano-surface energy transfer techniques are employed to examine the observed quenching behavior as a function of the characteristic donor-acceptor distances. The experimental results will find their relevance in light harvesting devices based on AAOs combined with other materials involving a decisive energy/charge transfer dynamics.

  19. Ultrafast excited state deactivation of doped porous anodic alumina membranes.

    PubMed

    Makhal, Abhinandan; Sarkar, Soumik; Pal, Samir Kumar; Yan, Hongdan; Wulferding, Dirk; Cetin, Fatih; Lemmens, Peter

    2012-08-03

    Free-standing, bi-directionally permeable and ultra-thin anodic aluminum oxide (AAO) membranes establish attractive templates (host) for the synthesis of nano-dots and rods of various materials (guest). This is due to their chemical and structural integrity and high periodicity on length scales of 5-150 nm which are often used to host photoactive nano-materials for various device applications including dye-sensitized solar cells. In the present study, AAO membranes are synthesized by using electrochemical methods and a detailed structural characterization using FEG-SEM, XRD and TGA confirms the porosity and purity of the material. Defect-mediated photoluminescence quenching of the porous AAO membrane in the presence of an electron accepting guest organic molecule (benzoquinone) is studied by means of steady-state and picosecond/femtosecond-resolved luminescence measurements. Using time-resolved luminescence transients, we have also revealed light harvesting of complexes of porous alumina impregnated with inorganic quantum dots (Maple Red) or gold nanowires. Both the Förster resonance energy transfer and the nano-surface energy transfer techniques are employed to examine the observed quenching behavior as a function of the characteristic donor-acceptor distances. The experimental results will find their relevance in light harvesting devices based on AAOs combined with other materials involving a decisive energy/charge transfer dynamics.

  20. Grafting of alginates on UF/NF ceramic membranes for wastewater treatment.

    PubMed

    Athanasekou, C P; Romanos, G E; Kordatos, K; Kasselouri-Rigopoulou, V; Kakizis, N K; Sapalidis, A A

    2010-10-15

    The mechanism of heavy metal ion removal in processes involving multi-layered tubular ultrafiltration and nanofiltration (UF/NF) membranes was investigated by conducting retention experiments in both flow-through and cross-flow modes. The prospect of the regeneration of the membranes through an acidic process was also examined and discussed. The UF/NF membranes were functionalised with alginates to develop hybrid inorganic/organic materials for continuous, single pass, wastewater treatment applications. The challenge laid in the induction of additional metal adsorption and improved regeneration capacity. This was accomplished by stabilizing alginates either into the pores or on the top-separating layer of the membrane. The preservation of efficient water fluxes at moderate trans-membrane pressures introduced an additional parameter that was pursued in parallel to the membrane modification process. The deposition and stabilization of alginates was carried out via physical (filtration/cross-linking) and chemical (grafting) procedures. The materials developed by means of the filtration process exhibited a 25-60% enhancement of their Cd(2+) binding capacity, depending on the amount of the filtered alginate solution. The grafting process led to the development of alginate layers with adequate stability under acidic regeneration conditions and metal retention enhancement of 25-180%, depending on the silane involved as grafting agent and the solvent of silanisation. 2010 Elsevier B.V. All rights reserved.

  1. Preparation and characterization of self-crosslinked organic/inorganic proton exchange membranes

    NASA Astrophysics Data System (ADS)

    Zhong, Shuangling; Cui, Xuejun; Dou, Sen; Liu, Wencong

    A series of silicon-containing sulfonated polystyrene/acrylate (Si-sPS/A) nanoparticles are successfully synthesized via simple emulsion polymerization method. The Si-sPS/A latexes show good film-forming capability and the self-crosslinked organic/inorganic proton exchange membranes are prepared by pouring the Si-sPS/A nanoparticle latexes into glass plates and drying at 60 °C for 10 h and 120 °C for 2 h. The potential of the membranes in direct methanol fuel cells (DMFCs) is characterized preliminarily by studying their thermal stability, ion-exchange capacity, water uptake, methanol diffusion coefficient, proton conductivity and selectivity (proton conductivity/methanol diffusion coefficient). The results indicate that these membranes possess excellent thermal stability and methanol barrier due to the existence of self-crosslinked silica network. In addition, the proton conductivity of the membranes is in the range of 10 -3-10 -2 S cm -1 and all the membranes show much higher selectivity in comparison with Nafion ® 117. These results suggest that the self-crosslinked organic/inorganic proton exchange membranes are particularly promising in DMFC applications.

  2. Membranes for Environmentally Friendly Energy Processes

    PubMed Central

    He, Xuezhong; Hägg, May-Britt

    2012-01-01

    Membrane separation systems require no or very little chemicals compared to standard unit operations. They are also easy to scale up, energy efficient, and already widely used in various gas and liquid separation processes. Different types of membranes such as common polymers, microporous organic polymers, fixed-site-carrier membranes, mixed matrix membranes, carbon membranes as well as inorganic membranes have been investigated for CO2 capture/removal and other energy processes in the last two decades. The aim of this work is to review the membrane systems applied in different energy processes, such as post-combustion, pre-combustion, oxyfuel combustion, natural gas sweetening, biogas upgrading, hydrogen production, volatile organic compounds (VOC) recovery and pressure retarded osmosis for power generation. Although different membranes could probably be used in a specific separation process, choosing a suitable membrane material will mainly depend on the membrane permeance and selectivity, process conditions (e.g., operating pressure, temperature) and the impurities in a gas stream (such as SO2, NOx, H2S, etc.). Moreover, process design and the challenges relevant to a membrane system are also being discussed to illustrate the membrane process feasibility for a specific application based on process simulation and economic cost estimation. PMID:24958426

  3. Advanced Hybrid Membranes for Next Generation PEMFC Automotive Applications.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Herring, Andrew M; Motz, Andrew R; Kuo, Mei-Chen

    The objective of this proposal is to fabricate a low cost high performance hybrid inorganic/polymer membrane that has a proton area specific resistance (ASR) < 0.02 ohm cm2 at the operating temperature of an automotive fuel cell stack (95 - 120°C) at low inlet RH <50% with good mechanical and chemical durability. Additionally the membrane will be optimized for low hydrogen and oxygen crossover with high electrical ASR at all temperatures and adequate proton ASR at lower temperatures. We also seek to gain valuable insights into rapid proton transport at the limit of proton hydration. Additional research will be performedmore » to incorporate the membrane into a 50 cm2 membrane electrode assembly (MEA). The materials at the start of this project are at a TRL of 2, as we have shown that they have proton conductivity under high and dry conditions, but we have not yet consistently shown that they will function in an operational fuel cell. At the project’s end the materials will be at a TRL of 4 and will be integrated into an MEA, demonstrating that they can function with electrodes as a single fuel cell.« less

  4. Nitrogen recovery from wastewater using gas-permeable membranes: Impact of inorganic carbon content and natural organic matter

    USDA-ARS?s Scientific Manuscript database

    Gas-permeable membranes coupled with low-rate aeration are useful to recover ammonium from livestock effluents. In this study, the role of inorganic carbon (bicarbonate) to enhance the nitrogen (N) recovery process was evaluated using synthetic effluents with various ammonium to bicarbonate molar ra...

  5. Application of a macrocyclic compound, bambus[6]uril, in tailor-made liquid membranes for highly selective electromembrane extractions of inorganic anions.

    PubMed

    Šlampová, Andrea; Šindelář, Vladimír; Kubáň, Pavel

    2017-01-15

    A tailor-made liquid membrane consisting of a resistive organic solvent (nitrobenzene, NB) and a highly selective non-ionic macrocyclic compound (bambus[6]uril, BU6) was employed for electromembrane extraction (EME) of inorganic anions. BU6 facilitates strong host-guest interactions of its internal cavity with selected inorganic anions only and its presence in the liquid membrane ensured excellent selectivity of the EME process. EME transfers were directly related to association constants between BU6 and inorganic anions and nearly absolute selectivity was achieved for EMEs of iodide, bromide and perchlorate. Major inorganic anions (chloride, nitrate, sulphate and carbonate), which exhibit low interactions with BU6 cavity, were efficiently eliminated from the EME transfer. No interferences were observed for EMEs of target analytes from samples containing up to 100.000-fold higher concentrations of the major anions. Addition of species-specific macrocyclic modifiers to free and supported liquid membranes might thus open new directions in fine-tuning of EME selectivity. At optimized EME conditions (polypropylene hollow fiber impregnated with NB + 3% (w/w) BU6, extraction voltage 25 V, extraction time 15 min, deionized water as acceptor solution) perchlorate was selectively extracted from tap water at concentrations below the guideline value recommended by United States Environmental Protection Agency. Excellent selectivity of the tailor-made liquid membrane was further demonstrated by EME of bromide from sea water. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Crystals: animal, vegetable or mineral?

    PubMed Central

    Hyde, Stephen T.

    2015-01-01

    The morphologies of biological materials, from body shapes to membranes within cells, are typically curvaceous and flexible, in contrast to the angular, facetted shapes of inorganic matter. An alternative dichotomy has it that biomolecules typically assemble into aperiodic structures in vivo, in contrast to inorganic crystals. This paper explores the evolution of our understanding of structures across the spectrum of materials, from living to inanimate, driven by those naive beliefs, with particular focus on the development of crystallography in materials science and biology. The idea that there is a clear distinction between these two classes of matter has waxed and waned in popularity through past centuries. Our current understanding, driven largely by detailed exploration of biomolecular structures at the sub-cellular level initiated by Bernal and Astbury in the 1930s, and more recent explorations of sterile soft matter, makes it clear that this is a false dichotomy. For example, liquid crystals and other soft materials are common to both living and inanimate materials. The older picture of disjoint universes of forms is better understood as a continuum of forms, with significant overlap and common features unifying biological and inorganic matter. In addition to the philosophical relevance of this perspective, there are important ramifications for science. For example, the debates surrounding extra-terrestrial life, the oldest terrestrial fossils and consequent dating of the emergence of life on the Earth rests to some degree on prejudices inferred from the supposed dichotomy between life-forms and the rest. PMID:26464788

  7. Crystals: animal, vegetable or mineral?

    PubMed

    Hyde, Stephen T

    2015-08-06

    The morphologies of biological materials, from body shapes to membranes within cells, are typically curvaceous and flexible, in contrast to the angular, facetted shapes of inorganic matter. An alternative dichotomy has it that biomolecules typically assemble into aperiodic structures in vivo, in contrast to inorganic crystals. This paper explores the evolution of our understanding of structures across the spectrum of materials, from living to inanimate, driven by those naive beliefs, with particular focus on the development of crystallography in materials science and biology. The idea that there is a clear distinction between these two classes of matter has waxed and waned in popularity through past centuries. Our current understanding, driven largely by detailed exploration of biomolecular structures at the sub-cellular level initiated by Bernal and Astbury in the 1930s, and more recent explorations of sterile soft matter, makes it clear that this is a false dichotomy. For example, liquid crystals and other soft materials are common to both living and inanimate materials. The older picture of disjoint universes of forms is better understood as a continuum of forms, with significant overlap and common features unifying biological and inorganic matter. In addition to the philosophical relevance of this perspective, there are important ramifications for science. For example, the debates surrounding extra-terrestrial life, the oldest terrestrial fossils and consequent dating of the emergence of life on the Earth rests to some degree on prejudices inferred from the supposed dichotomy between life-forms and the rest.

  8. Surface modification of thin film composite membrane by nanoporous titanate nanoparticles for improving combined organic and inorganic antifouling properties.

    PubMed

    Emadzadeh, D; Ghanbari, M; Lau, W J; Rahbari-Sisakht, M; Rana, D; Matsuura, T; Kruczek, B; Ismail, A F

    2017-06-01

    In this study, nanoporous titanate (NT) nanoparticle synthesized by the solvothermal method was used to modify polyamide layer of thin film composite membranes with the aim of improving membrane resistances against organic and inorganic fouling. Thin film nanocomposite membranes (NMs) were synthesized by adding mNTs (modified nanoparticles) into polyamide selective layer followed by characterization using different analytical instruments. The results of XPS and XRD confirmed the presence of mNTs in the polyamide layer of NMs, while FESEM, AFM, zeta potential and contact angle measurement further supported the changes in physical and chemical properties of the membrane surface upon mNTs incorporation. Results of fouling showed that NM1 (the membrane incorporated with 0.01w/v% mNTs) always demonstrated lower degree of flux decline compared to the control membrane when membranes were tested with organic, inorganic and multicomponent synthesized water, brackish water or seawater. Besides showing greater antifouling resistance, the NM also displayed significantly higher water flux compared to the control M membrane. The findings of this work confirmed the positive impact of mNTs in improving the properties of NM with respect to fouling mitigation and flux improvement. Copyright © 2017. Published by Elsevier B.V.

  9. Characterization of Pores in Dense Nanopapers and Nanofibrillated Cellulose Membranes: A Critical Assessment of Established Methods.

    PubMed

    Orsolini, Paola; Michen, Benjamin; Huch, Anja; Tingaut, Philippe; Caseri, Walter R; Zimmermann, Tanja

    2015-11-25

    Nanofibrillated cellulose (NFC) is a natural fibrous material that can be readily processed into membranes. NFC membranes for fluid separation work in aqueous medium, thus in their swollen state. The present study is devoted to a critical investigation of porosity, pore volume, specific surface area, and pore size distribution of dry and wet NFC nanopapers, also known as membranes, with various established techniques, such as electron microscopy, helium pycnometry, mercury intrusion, gas adsorption (N2 and Kr), and thermoporometry. Although these techniques can be successfully applied to inorganic materials (e.g., mesoporous silica), it is necessary to appraise them for organic and hydrophilic products such as NFC membranes. This is due to different phenomena occurring at the materials interfaces with the probing fluids. Mercury intrusion and gas adsorption are often used for the characterization of porosity-related properties; nevertheless, both techniques characterize materials in the dry state. In parallel, thermoporometry was employed to monitor the structure changes upon swelling, and a water permeance test was run to show the accessibility of the membranes to fluids. For the first time, the methods were systematically screened, and we highlighted the need of uniform sample treatments prior to the measurements (i.e., sample cutting and outgassing protocols) in order to harmonize results from the literature. The need for revising the applicability range of mercury intrusion and the inappropriateness of nitrogen adsorption were pointed out. We finally present a table for selecting the most appropriate method to determine a desired property and propose guidelines for results interpretation from which future users could profit.

  10. Light metal production

    DOEpatents

    Fan, Qinbai

    2016-04-19

    An electrochemical process for the production of light metals, particularly aluminum. Such a process involves contacting a light metal source material with an inorganic acid to form a solution containing the light metal ions in high concentration. The solution is fed to an electrochemical reactor assembly having an anode side containing an anode and a cathode side containing a cathode, with anode side and the cathode side separated by a bipolar membrane, with the solution being fed to the anode side. Light metal ions are electrochemically transferred through the bipolar membrane to the cathode side. The process further involves reducing the light metal ions to light metal powder. An associated processing system is also provided.

  11. Development of composite membranes of PVA-TEOS doped KOH for alkaline membrane fuel cell

    NASA Astrophysics Data System (ADS)

    Haryadi, Sugianto, D.; Ristopan, E.

    2015-12-01

    Anion exchange membranes (AEMs) play an important role in separating fuel and oxygen (or air) in the Alkaline Membrane Fuel Cells. Preparation of hybrid organic inorganic materials of Polyvinylalcohol (PVA) - Tetraethylorthosilicate (TEOS) composite membrane doped KOH for direct alcohol alkaline fuel cell application has been investigated. The sol-gel method has been used to prepare the composite membrane of PVA-TEOS through crosslinking step and catalyzed by concentrated of hydrochloric acid. The gel solution was cast on the membrane plastic plate to obtain membrane sheets. The dry membranes were then doped by immersing in various concentrations of KOH solutions for about 4 hours. Investigations of the cross-linking process and the presence of hydroxyl group were conducted by FTIR as shown for frequency at about 1600 cm-1 and 3300 cm-1 respectively. The degree of swelling in ethanol decreased as the KOH concentration for membrane soaking process increased. The ion exchange capacity (IEC) of the membrane was 0.25meq/g. This composite membranes display significant ionic conductivity of 3.23 x 10-2 S/cm in deionized water at room temperature. In addition, the morphology observation by scanning electron microscope (SEM) of the membrane indicates that soaking process of membrane in KOH increased thermal resistant.

  12. Development of taste sensing system using inorganic membrane

    NASA Astrophysics Data System (ADS)

    Kojima, Yohichiro; Hasegawa, Yuki

    2011-09-01

    We developed a novel taste sensor for liquid and verified its effectiveness using coffee. We fabricated an inorganic metal oxide membrane liquid sensor using the laser ablation method. The sensor shows a sufficient sensitivity for electrolyte solutions, while it shows a relatively low response for non-electrolyte solutions. We differentiated and identified five brands of commercially available coffee using the sensor.

  13. Fouling characteristics of reverse osmosis membranes at different positions of a full-scale plant for municipal wastewater reclamation.

    PubMed

    Tang, Fang; Hu, Hong-Ying; Sun, Li-Juan; Sun, Ying-Xue; Shi, Na; Crittenden, John C

    2016-03-01

    Membrane fouling is an important shortcoming limiting the efficiency and wide application of reverse osmosis (RO) technology. In this paper, RO membranes in a full-scale municipal wastewater reclamation plant were autopsied. From the lead to tail position RO membranes in RO system, both of organic and inorganic matters on membranes reduced gradually. The higher ion products in RO concentrate didn't result in more serious inorganic scaling on the last position RO membranes, which was contrast with some other researches. Fe, Ca and Mg were major inorganic elements. Fe had a relatively low concentration in RO influent but the highest content on membranes. However, there was no specific pretreatment in terms of Fe removal. Ca and Mg scaling was controlled by the antiscalants injected. Organic fouling (75.0-84.5% of dry weights) was major problem on RO membranes due to the large amount of dissolved organic matters in secondary effluent as raw water. Hydrophilic acid (HIA, 48.0% of total DOC), hydrophobic acid (HOA, 23.6%) and hydrophobic neutral (HON, 19.0%) fraction was largest among the six fractions in RO influent, while HON (38.2-51.1%) and HOA (22.1-26.1%) tended to accumulate on membranes in higher quantities. Monitoring HON and HOA might help to forecast organic fouling. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Biological interaction of living cells with COSAN-based synthetic vesicles

    PubMed Central

    Tarrés, Màrius; Canetta, Elisabetta; Paul, Eleanor; Forbes, Jordan; Azzouni, Karima; Viñas, Clara; Teixidor, Francesc; Harwood, Adrian J.

    2015-01-01

    Cobaltabisdicarbollide (COSAN) [3,3′-Co(1,2-C2B9H11)2]−, is a complex boron-based anion that has the unusual property of self-assembly into membranes and vesicles. These membranes have similar dimensions to biological membranes found in cells, and previously COSAN has been shown to pass through synthetic lipid membranes and those of living cells without causing breakdown of membrane barrier properties. Here, we investigate the interaction of this inorganic membrane system with living cells. We show that COSAN has no immediate effect on cell viability, and cells fully recover when COSAN is removed following exposure for hours to days. COSAN elicits a range of cell biological effects, including altered cell morphology, inhibition of cell growth and, in some cases, apoptosis. These observations reveal a new biology at the interface between inorganic, synthetic COSAN membranes and naturally occurring biological membranes. PMID:25588708

  15. Biological interaction of living cells with COSAN-based synthetic vesicles.

    PubMed

    Tarrés, Màrius; Canetta, Elisabetta; Paul, Eleanor; Forbes, Jordan; Azzouni, Karima; Viñas, Clara; Teixidor, Francesc; Harwood, Adrian J

    2015-01-15

    Cobaltabisdicarbollide (COSAN) [3,3'-Co(1,2-C2B9H11)2](-), is a complex boron-based anion that has the unusual property of self-assembly into membranes and vesicles. These membranes have similar dimensions to biological membranes found in cells, and previously COSAN has been shown to pass through synthetic lipid membranes and those of living cells without causing breakdown of membrane barrier properties. Here, we investigate the interaction of this inorganic membrane system with living cells. We show that COSAN has no immediate effect on cell viability, and cells fully recover when COSAN is removed following exposure for hours to days. COSAN elicits a range of cell biological effects, including altered cell morphology, inhibition of cell growth and, in some cases, apoptosis. These observations reveal a new biology at the interface between inorganic, synthetic COSAN membranes and naturally occurring biological membranes.

  16. Method of making chalcogen catalysts for polymer electrolyte fuel cells

    DOEpatents

    Choi, Jong-Ho; Zelenay, Piotr; Wieckowski, Andrzej; Cao, Dianxue

    2010-12-14

    A method of making an electrode catalyst material using aqueous solutions. The electrode catalyst material includes a support comprising at least one transition metal and at least one chalcogen disposed on a surface of the transition metal. The method includes reducing a metal powder, mixing the metal powder with an aqueous solution containing at least one inorganic compound of the chalcogen to form a mixture, and providing a reducing agent to the mixture to form nanoparticles of the electrode catalyst. The electrode catalyst may be used in a membrane electrode assembly for a fuel cell.

  17. Evaluation of Removal Mechanisms in a Graphene Oxide-Coated Ceramic Ultrafiltration Membrane for Retention of Natural Organic Matter, Pharmaceuticals, and Inorganic Salts.

    PubMed

    Chu, Kyoung Hoon; Fathizadeh, Mahdi; Yu, Miao; Flora, Joseph R V; Jang, Am; Jang, Min; Park, Chang Min; Yoo, Sung Soo; Her, Namguk; Yoon, Yeomin

    2017-11-22

    Functionalized graphene oxide (GO), derived from pure graphite via the modified Hummer method, was used to modify commercially available ceramic ultrafiltration membranes using the vacuum method. The modified ceramic membrane functionalized with GO (ceramic GO ) was characterized using a variety of analysis techniques and exhibited higher hydrophilicity and increased negative charge compared with the pristine ceramic membrane. Although the pure water permeability of the ceramic GO membrane (14.4-58.6 L/m 2 h/bar) was slightly lower than that of the pristine membrane (25.1-62.7 L/m 2 h/bar), the removal efficiencies associated with hydrophobic attraction and charge effects were improved significantly after GO coating. Additionally, solute transport in the GO nanosheets of the ceramic GO membrane played a vital role in the retention of target compounds: natural organic matter (NOM; humic acid and tannic acid), pharmaceuticals (ibuprofen and sulfamethoxazole), and inorganic salts (NaCl, Na 2 SO 4 , CaCl 2 , and CaSO 4 ). While the retention efficiencies of NOM, pharmaceuticals, and inorganic salts in the pristine membrane were 74.6%, 15.3%, and 2.9%, respectively, these increased to 93.5%, 51.0%, and 31.4% for the ceramic GO membrane. Consequently, the improved removal mechanisms of the membrane modified with functionalized GO nanosheets can provide efficient retention for water treatment under suboptimal environmental conditions of pH and ionic strength.

  18. How different is the composition of the fouling layer of wastewater reuse and seawater desalination RO membranes?

    PubMed

    Khan, Muhammad Tariq; Busch, Markus; Molina, Veronica Garcia; Emwas, Abdul-Hamid; Aubry, Cyril; Croue, Jean-Philippe

    2014-08-01

    To study the effect of water quality and operating parameters on membrane fouling, a comparative analysis of wastewater (WW) and seawater (SW) fouled reverse osmosis (RO) membranes was conducted. Membranes were harvested from SWRO and WWRO pilot plants located in Vilaseca (East Spain), both using ultrafiltration as pretreatment. The SWRO unit was fed with Mediterranean seawater and the WWRO unit was operated using secondary effluent collected from the municipal wastewater treatment plant. Lead and terminal SWRO and WWRO modules were autopsied after five months and three months of operation, respectively. Ultrastructural, chemical, and microbiological analyses of the fouling layers were performed. Results showed that the WWRO train had mainly bio/organic fouling at the lead position element and inorganic fouling at terminal position element, whereas SWRO train had bio/organic fouling at both end position elements. In the case of WWRO membranes, Betaproteobacteria was the major colonizing species; while Ca, S, and P were the major present inorganic elements. The microbial population of SWRO membranes was mainly represented by Alpha and Gammaproteobacteria. Ca, Fe, and S were the main identified inorganic elements of the fouling layer of SWRO membranes. These results confirmed that the RO fouling layer composition is strongly impacted by the source water quality. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Bismuth citrate in the quantification of inorganic phosphate and its utility in the determination of membrane-bound phosphatases.

    PubMed

    Cariani, L; Thomas, L; Brito, J; del Castillo, J R

    2004-01-01

    This paper describes a rapid and sensitive method to determine inorganic phosphate, even in the presence of labile organic phosphate compounds and large quantities of proteins. The method eliminates the use of sodium arsenite, a highly toxic compound, substituting bismuth citrate for it to stabilize the phosphomolybdic acid complex formed during the interaction of inorganic phosphate and molybdate reduced by ascorbic acid. This method has also been adapted to microplates and has been used to determine the activities of Na/K ATPase and alkaline phosphatase of intestinal basolateral and luminal plasma membranes.

  20. The viability of MCM-41 as separator in secondary alkaline cells

    NASA Astrophysics Data System (ADS)

    Meskon, S. R.; Othman, R.; Ani, M. H.

    2018-01-01

    The viability of MCM-41 membrane as a separator material in secondary alkaline cell is investigated. The inorganic membrane was employed in an alkaline nickel-zinc system. MCM-41 mesoporous material consists of arrays of hexagonal nano-pore channels. The membrane was synthesized using sol-gel route from parent solution comprising of quarternary ammonium surfactant, cethyltrimethylammonium bromide C16H33(CH3)3NBr (CTAB), hydrochloric acid (HCl), deionized water (H2O), ethanol (C2H5OH), and tetraethylortosilicate (TEOS). Both the anodic zinc/zinc oxide and cathodic nickel hydroxide electrodeposited film were coated with MCM-41 membrane. The Ni/MCM-41/Zn alkaline cell was then subjected to 100-cycle durability test and the structural stability of MCM-41 separator throughout the progression of the charge-discharge cycles is studied. X-ray diffraction (XRD) analysis on the dismantled cell shows that MCM-41 began to transform to lamellar MCM-50 on the 5th cycle and transformed almost completely on the 25th cycle. The phase transformation of MCM-41 hexagonal structure into gel-like MCM-50 prevents the mesoporous cell separator from diminished in the caustic alkaline surround. This work has hence demonstrated MCM-41 membrane is viable to be employed in secondary alkaline cells.

  1. MIL-53 frameworks in mixed-matrix membranes and cross-linked ZIF-8/matrimidRTM mixed-matrix membranes for gas separation

    NASA Astrophysics Data System (ADS)

    Hsieh, Josephine Ordonez

    Mixed matrix membranes (MMMs) are hybrid materials consisting of two phases: an inorganic nanoscale particle as the discrete phase, and a polymeric material as the continuous phase. The incorporation of inorganic particles into a polymer can improve a membrane's overall separation performance. MMMs incorporating metal-organic frameworks (MOFs) have exhibited promising gas separation performance. MOFs are inorganic-organic crystals constructed from metal ions that are linked by polydentate ligands. Zeolitic imidazolate frameworks (ZIFs) are a sub-class of MOFs that uses imidazole analogues as ligands. In these studies, the MOF MIL-53 and ZIF-8 were successfully synthesized and characterized by a battery of analytical techniques including XRD, FTIR, TGA, N2 adsorption, and SEM, and were incorporated into MMMs with Matrimid® polymer. In chapter 1, MIL-53/Matrimid® MMMs containing MIL-53-ht (open-pore form) were fabricated, characterized and obtained permeability values higher than Matrimid®. Selectivities decreased for the gas pairs of O2/N2, H2/O2, H2/CO2, and H2/N2. However, slight enhancement of the CO2/CH4 selectivity was observed for the MIL-53-ht/Matrimid® compared to that of Matrimid ®. The MIL-53-as/Matrimid® MMM also showed an increase in permeability as well as an increase in selectivity for the gas pairs H2/O2, CO2/CH4, H 2/CH4, and H2/N2. The MIL-53-lt/Matrimid ® MMM showed that it does not retain its closed-pore form in the MMM due to chloroform solvent opening the pores and eventually polymer confinement of the MIL 53 framework in the MMM. In chapter 2, easy synthesis and fabrication of the MIL-53 MOF membrane was realized using a seeded growth method with a commercially available alumina TLC plate. The MOF membrane had a well-intergrown and dense layer of MIL-53 crystals on the surface of the alumina substrate. The MIL-53 crystals were also converted to the MIL-53-lt (closed-pore form) after heating at 330 °C and cooling to room temperature, which confirms the breathing ability of the MOF. In chapter 3, a comprehensive approach for membrane materials in order to achieve high productivity and separation efficiency was applied by incorporating additives into polymers and cross-linking the resulting MMM that could lead to increase and simultaneous selectivity enhancement. ZIF-8 was used as an additive in these MMMs. ZIF-8 can readily absorb small gases such, as H 2 and CO2 due to its 3.4 Å pore aperture. ZIF-8/Matrimid ® MMMs were fabricated with a spin-coated Matrimid® layer on one surface and cross-linked with EDA vapor. This membrane morphology could lead to enhanced selectivities due to the cross-linked layer, at the same time maintain the high permeability of the bulk MMM. The permeabilities decreased for the cross-linked, spin-coated Matrimid® ZIF-8/Matrimid ® MMMs. However, there was enhancement in selectivities for H 2/CO2, H2/N2, H2/O 2 and H2/CH4 gas pairs, which can be due to reduction of diffusive pathways for larger gas molecules. Compared to uncross-linked ZIF-8/Matrimid® MMMs, the cross-linked, spin-coated Matrimid ® ZIF-8/Matrimid® MMMs lie close to the Robeson's upper bound for H2/CO2 suggesting its potential for this gas pair separation.

  2. Effect of non-solvent additives on the morphology, pore structure, and direct contact membrane distillation performance of PVDF-CTFE hydrophobic membranes.

    PubMed

    Zheng, Libing; Wu, Zhenjun; Zhang, Yong; Wei, Yuansong; Wang, Jun

    2016-07-01

    Four common types of additives for polymer membrane preparation including organic macromolecule and micromolecule additives, inorganic salts and acids, and the strong non-solvent H2O were used to prepare poly (vinylidene fluoride-co-chlorotrifluoroethylene) (PVDF-CTFE) hydrophobic flat-sheet membranes. Membrane properties including morphology, porosity, hydrophobicity, pore size and pore distribution were investigated, and the permeability was evaluated via direct contact membrane distillation (DCMD) of 3.5g/L NaCl solution in a DCMD configuration. Both inorganic and organic micromolecule additives were found to slightly influence membrane hydrophobicity. Polyethylene glycol (PEG), organic acids, LiCl, MgCl2, and LiCl/H2O mixtures were proved to be effective additives to PVDF-CTFE membranes due to their pore-controlling effects and the capacity to improve the properties and performance of the resultant membranes. The occurrence of a pre-gelation process showed that when organic and inorganic micromolecules were added to PVDF-CTFE solution, the resultant membranes presented a high interconnectivity structure. The membrane prepared with dibutyl phthalate (DBP) showed a nonporous surface and symmetrical cross-section. When H2O and LiCl/H2O mixtures were also used as additives, they were beneficial for solid-liquid demixing, especially when LiCl/H2O mixed additives were used. The membrane prepared with 5% LiCl+2% H2O achieved a flux of 24.53kg/(m(2)·hr) with 99.98% salt rejection. This study is expected to offer a reference not only for PVDF-CTFE membrane preparation but also for other polymer membranes. Copyright © 2016. Published by Elsevier B.V.

  3. Outer Membrane Permeability of Cyanobacterium Synechocystis sp. Strain PCC 6803: Studies of Passive Diffusion of Small Organic Nutrients Reveal the Absence of Classical Porins and Intrinsically Low Permeability

    PubMed Central

    Kowata, Hikaru; Tochigi, Saeko; Takahashi, Hideyuki

    2017-01-01

    ABSTRACT The outer membrane of heterotrophic Gram-negative bacteria plays the role of a selective permeability barrier that prevents the influx of toxic compounds while allowing the nonspecific passage of small hydrophilic nutrients through porin channels. Compared with heterotrophic Gram-negative bacteria, the outer membrane properties of cyanobacteria, which are Gram-negative photoautotrophs, are not clearly understood. In this study, using small carbohydrates, amino acids, and inorganic ions as permeation probes, we determined the outer membrane permeability of Synechocystis sp. strain PCC 6803 in intact cells and in proteoliposomes reconstituted with outer membrane proteins. The permeability of this cyanobacterium was >20-fold lower than that of Escherichia coli. The predominant outer membrane proteins Slr1841, Slr1908, and Slr0042 were not permeable to organic nutrients and allowed only the passage of inorganic ions. Only the less abundant outer membrane protein Slr1270, a homolog of the E. coli export channel TolC, was permeable to organic solutes. The activity of Slr1270 as a channel was verified in a recombinant Slr1270-producing E. coli outer membrane. The lack of putative porins and the low outer membrane permeability appear to suit the cyanobacterial autotrophic lifestyle; the highly impermeable outer membrane would be advantageous to cellular survival by protecting the cell from toxic compounds, especially when the cellular physiology is not dependent on the uptake of organic nutrients. IMPORTANCE Because the outer membrane of Gram-negative bacteria affects the flux rates for various substances into and out of the cell, its permeability is closely associated with cellular physiology. The outer membrane properties of cyanobacteria, which are photoautotrophic Gram-negative bacteria, are not clearly understood. Here, we examined the outer membrane of Synechocystis sp. strain PCC 6803. We revealed that it is relatively permeable to inorganic ions but is markedly less permeable to organic nutrients, with >20-fold lower permeability than the outer membrane of Escherichia coli. Such permeability appears to fit the cyanobacterial lifestyle, in which the diffusion pathway for inorganic solutes may suffice to sustain the autotrophic physiology, illustrating a link between outer membrane permeability and the cellular lifestyle. PMID:28696278

  4. The presence and distribution of polycyclic aromatic hydrocarbons and inorganic elements in water and lakebed materials and the potential for bioconcentration in biota at established sampling sites on Lake Powell, Utah and Arizona

    USGS Publications Warehouse

    Schonauer, Kurt T.; Hart, Robert J.; Antweiler, Ronald C.

    2014-01-01

    The National Park Service is responsible for monitoring the effects of visitor use on the quality of water, lakebed material (bottom sediments), and biota, in Lake Powell, Utah and Arizona. A sampling program was begun in 2010 to assess the presence, distribution, and concentrations of organic and inorganic compounds in the water column and bottom sediment. In response to an Environmental Impact Statement regarding personal watercraft and as a continuation from previous studies by the U.S. Geological Survey and the National Park Service, Glen Canyon National Recreation Area, water samples were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) using semipermeable membrane devices and inorganic elements using a fixed-bottle sampler deployed at established monitoring sites during 2010 and 2011. Lakebed material samples were also analyzed for polycyclic aromatic hydrocarbons and inorganic elements, some of which could be harmful to aquatic biota if present at concentrations above established aquatic life criteria. Of the 44 PAH compounds analyzed, 26 individual compounds were detected above the censoring limit in the water column by semipermeable membrane devices. The highest number of compounds detected were at Lone Rock Beach, Wahweap Marina, Rainbow Bridge National Monument, and Antelope Marina which are all located in the southern part of Lake Powell where visitation and boat use is high. Because PAHs can remain near their source, the potential for bioconcentration is highest near these sites. The PAH compound found in the highest concentration was phenol (5,902 nanograms per liter), which is included in the U.S. Environmental Protection Agency’s priority pollutants list. The dissolved inorganic chemistry of water samples measured at the sampling sites in Lake Powell defined three different patterns of elements: (1) concentrations were similar between sites in the upper part of the lake near Farley Canyon downstream to Halls Crossing Marina, a distance of about 36 lake miles, (2) concentrations varied depending on the element between Halls Crossing Marina downstream to the mouth of the Escalante River, a distance of about 33 lake miles, and (3) concentrations were similar between sites from below the mouth of the Escalante River to Glen Canyon Dam, a distance of about 68 lake miles. Analysis of lakebed bottom sediment material samples detected PAH compounds at all sampling sites except at Halls Crossing Marina, Stanton Creek, and Forgotten Canyon. Twenty-four of 44 PAHs analyzed in lakebed material were detected above the reporting limit. Perylene was the most prevalent compound detected above the reporting limit in lakebed material and was detected at three sampling sites. Concentrations of perylene ranged from an estimate of 24.0 to 47.9 micrograms per kilogram (μg/kg). Fluoranthene had the highest concentration of any PAH and was detected at the Wahweap Marina with a concentration of 565 μg/kg. The highest sum of concentrations for all compounds found in lakebed material samples at one site was at the Wahweap Marina, which had concentrations five times higher than the next highest site. The three major tributaries to Lake Powell—the Colorado, Escalante, and San Juan Rivers—all showed elevated concentrations of inorganic elements in their delta sediments for most elements relative to the majority of the sediment samples taken from the lake itself. However, there were four lake sites that had concentrations for most inorganic elements that equaled or exceeded those of the tributaries. Two of these sites were at the northeast part of the lake, nearest to the Colorado River as it enters Lake Powell (Farley Canyon and Blue Notch Canyon), one was at the Escalante River below 50-Mile Canyon, and other was at Antelope Marina.

  5. Infiltration of methylammonium metal halide in highly porous membranes using sol-gel-derived coating method

    NASA Astrophysics Data System (ADS)

    Kwon, Seung Lee; Jin, Young Un; Kim, Byeong Jo; Han, Man Hyung; Han, Gill Sang; Shin, Seunghak; Lee, Sangwook; Jung, Hyun Suk

    2017-09-01

    Organic-inorganic halide perovskites (OIHPs) has emerged as promising optoelectronic materials for solar cells and light-emitting diodes. OIHPs are usually coated on a flat surface or mesoporous scaffold for the applications. Herein, we report a facile sol-gel-derived solution route for coating methylammonium lead iodide (MAPbI3) perovskite layers onto various nanoporous structures. We found that lead-acetate solution has superior infiltration property onto surface of oxide membranes, and it can easily be converted to MAPbI3 by sequential transform to PbO, PbI2, and finally MAPbI3. Excellent pore-filling and full coverage of the nanostructures with the final MAPbI3 perovskite material are demonstrated via this sol-gel-derived solution route, using mesoporous TiO2, TiO2 nanorods, and high-aspect ratio nanopores in anodic aluminum oxide membranes. Given that this sol-gel-based method fills nanopores better than other conventional coating methods for OIHPs, this method may find wide applications in nanostructured OIHPs-based optoelectronic systems.

  6. Dehydration of an ethanol/water azeotrope by novel organic-inorganic hybrid membranes based on quaternized chitosan and tetraethoxysilane.

    PubMed

    Uragami, Tadashi; Katayama, Takuya; Miyata, Takashi; Tamura, Hiroshi; Shiraiwa, Tadashi; Higuchi, Akon

    2004-01-01

    To control swelling of quaternized chitosan (q-Chito) membranes, mixtures of q-Chito as an organic component and tetraethoxysilane (TEOS) as an inorganic component were prepared using the sol-gel reaction, and novel q-Chito/TEOS hybrid membranes were formed. In the separation of an ethanol/water azeotrope by pervaporation, the effect of TEOS content on the water/ethanol selectivity of q-Chito/TEOS hybrid membranes was investigated. Hybrid membranes containing up to 45 mol % TEOS exhibited higher water/ethanol selectivity than the q-Chito membrane. This resulted from depressed swelling of the membranes by formation of a cross-linked structure. However, introduction of excess TEOS led to greater swelling of the hybrid membranes. Therefore, the water/ethanol selectivity of the hybrid membranes containing more than 45 mol % TEOS was lower than that of the q-Chito membrane. The relationship between the structure of q-Chito/TEOS hybrid membranes and their permeation and separation characteristics during pervaporation of an ethanol/water azeotrope is discussed in detail.

  7. Preliminary study on gas separation performance of flat sheet mixed matrix (PVDF/Zeolite)

    NASA Astrophysics Data System (ADS)

    Rahman, Sunarti Abd; Abdalla Suliman Haron, Gamal; Krishna Roshan Kanasan, Raj; Hasbullah, Hasrinah

    2018-04-01

    Membrane separation has attracted a lot of attention over the last years mainly due to its separation ability, operational capability and economical viability. Mixed matrix membrane (MMM) combines the superior transport and selectivity properties of inorganic membrane materials and the excellent fabrication properties of organic polymers. This emerging technology can be utilized to purify biogas which can be used in a variety of applications. In this study, flat sheet mixed matrix membranes were synthesized with different percentages of N-Mehtyl-2-pyrrolidone (NMP) as solvent, Polyvinylidene Fluoride (PVDF) as the polymer matrix and zeolite 4A as the dispersed fine particles, membrane A (80: 20: 0), membrane B (80: 18: 2), membrane C (80: 15: 5), and membrane D (75: 15: 10) respectively. The membranes were fabricated using dry/wet phase inversion method. The membrane’s performance in terms of permeability and selectivity was examined using the single gas permeation device. The general trend was that, the permeability of the two gases (CO2/CH4) decreased with the increase of the pressure (0.5, 1, 1.5) bar. Membrane D was found to be suitable to separate the pair gas (CO2/CH4) as the permeability was 65623.412, Barrer and 15587.508, Barrer respectively, and its selectivity for was 4.21 at 0.5 bar.

  8. Development of composite membranes of PVA-TEOS doped KOH for alkaline membrane fuel cell

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Haryadi,, E-mail: haryadi@polban.ac.id; Sugianto, D.; Ristopan, E.

    2015-12-29

    Anion exchange membranes (AEMs) play an important role in separating fuel and oxygen (or air) in the Alkaline Membrane Fuel Cells. Preparation of hybrid organic inorganic materials of Polyvinylalcohol (PVA) - Tetraethylorthosilicate (TEOS) composite membrane doped KOH for direct alcohol alkaline fuel cell application has been investigated. The sol-gel method has been used to prepare the composite membrane of PVA-TEOS through crosslinking step and catalyzed by concentrated of hydrochloric acid. The gel solution was cast on the membrane plastic plate to obtain membrane sheets. The dry membranes were then doped by immersing in various concentrations of KOH solutions for aboutmore » 4 hours. Investigations of the cross-linking process and the presence of hydroxyl group were conducted by FTIR as shown for frequency at about 1600 cm{sup −1} and 3300 cm{sup −1} respectively. The degree of swelling in ethanol decreased as the KOH concentration for membrane soaking process increased. The ion exchange capacity (IEC) of the membrane was 0.25meq/g. This composite membranes display significant ionic conductivity of 3.23 x 10{sup −2} S/cm in deionized water at room temperature. In addition, the morphology observation by scanning electron microscope (SEM) of the membrane indicates that soaking process of membrane in KOH increased thermal resistant.« less

  9. Nanocrystal solar cells processed from solution

    DOEpatents

    Alivisatos, A. Paul; Gur, Ilan; Milliron, Delia

    2013-05-14

    A photovoltaic device having a first electrode layer, a high resistivity transparent film disposed on the first electrode, a second electrode layer, and an inorganic photoactive layer disposed between the first and second electrode layers, wherein the inorganic photoactive layer is disposed in at least partial electrical contact with the high resistivity transparent film, and in at least partial electrical contact with the second electrode. The photoactive layer has a first inorganic material and a second inorganic material different from the first inorganic material, wherein the first and second inorganic materials exhibit a type II band offset energy profile, and wherein the photoactive layer has a first population of nanostructures of a first inorganic material and a second population of nanostructures of a second inorganic material.

  10. Effect of "bridge" on the performance of organic-inorganic crosslinked hybrid proton exchange membranes via KH550

    NASA Astrophysics Data System (ADS)

    Han, Hailan; Li, Hai Qiang; Liu, Meiyu; Xu, Lishuang; Xu, Jingmei; Wang, Shuang; Ni, Hongzhe; Wang, Zhe

    2017-02-01

    A series of novel organic-inorganic crosslinked hybrid proton exchange membranes were prepared using sulfonated poly(arylene ether ketone sulfone) polymers containing carboxyl groups (C-SPAEKS), (3-aminopropyl)-triethoxysilane (KH550), and tetraethoxysilane (TEOS). KH550 acted as a "bridge" after reacting with carboxyl and sulfonic groups of C-SPAEKS to form covalent and ionic crosslinked structure between the C-SPAEKS and SiO2 phase. The crosslinked hybrid membranes (C-SPAEKS/K-SiO2) were characterized by FT-IR spectroscopy, TGA, and electrochemistry, etc. The thermal stability, mechanical properties and proton conductivity of the crosslinked hybrid membranes were improved by the presence of both crosslinked structure and inorganic phase. The proton conductivity of C-SPAEKS/K-SiO2-8 was recorded as 0.110 S cm-1, higher than that of Nafion® (0.028 S cm-1) at 120 °C. Moreover, the methanol permeability of the C-SPAEKS/K-SiO2-8 was measured as 3.86 × 10-7 cm2 s-1, much lower than that of Nafion® 117 membranes (29.4 × 10-7 cm2 s-1) at 25 °C.

  11. Inorganic spark chamber frame and method of making the same

    NASA Technical Reports Server (NTRS)

    Heslin, T. M. (Inventor)

    1982-01-01

    A spark chamber frame, manufactured using only inorganic materials is described. The spark chamber frame includes a plurality of beams formed from inorganic material, such as ceramic or glass, and are connected together at ends with inorganic bonding material having substantially the same thermal expansion as the beam material. A plurality of wires formed from an inorganic composition are positioned between opposed beams so that the wires are uniformly spaced and form a grid. A plurality of hold down straps are formed of inorganic material such as ceramic or glass having substantially the same chemical and thermal properties as the beam material. Hold down straps overlie wires extending over the beams and are bonded thereto with inorganic bonding material.

  12. [Mode of action of plantaricin L-1, an antilisteria bacteriocin produced by Lactobacillus plantarum].

    PubMed

    Zhou, Wei; Liu, Guo-rong; Li, Ping-lan; Dai, Yun-qing; Zhou, Kang

    2007-04-01

    Plantaricin L-1, an anti-Listeria bacteriocin, was produced by Lactobacillus plantarum and successfully purified by SP-Sepharose FF cation exchange chromatography. The mechanism on energized cells of Listeria monocytogenes was studied with purified plantaricin L-1. After adding plantaricin L-1 to Listeria monocytogenes at 64 AU/mL, leakage of intercellular K+ ions, inorganic phosphate, lactic dehydrogenase, UV-absorbing materials and the intracellular ATP was observed, and the action resulted in the dissipation of the membrane potential (delta psi) and pH gradient (delta psi), two components of the proton motive force (PMF). All the data suggested that the primary site of action of plantaricin L-1 was the cytoplasmic membrane of sensitive cells. By forming the nonselective pores which leak ions and small organic compounds plantaricin L-1 induced the cells death, this action was similar to membrane corruption caused by peptide effect. Penetrability increased due to the enlarged pore and dysfuction of membrane transporters, which ensured efficient killing of target bacteria.

  13. Impact of PAC Fines in Fouling of Polymeric and Ceramic Low-Pressure Membranes for Drinking Water Treatment

    PubMed Central

    Oligny, Laurent; Bérubé, Pierre R.; Barbeau, Benoit

    2016-01-01

    This study assessed the issue of membrane fouling in a Hybrid Membrane Process (HMP) due to the export of powdered activated carbon (PAC) fines from a pretreatment contactor. Two parallel pilot-scale ceramic and polymeric membranes were studied. Reversible and irreversible foulings were measured following three cleaning procedures: Physical backwashing (BW), chemically enhanced backwashing (CEB) and Clean-in-Place (CIP). The impacts on fouling of membrane type, operation flux increase and the presence/absence of the PAC pretreatment were investigated. Membranes without pretreatment were operated in parallel as a control. In addition, CIP washwaters samples were analyzed to measure organic and inorganic foulants removed from the membranes. It was observed that for the polymeric membranes, fouling generally increased with the presence of the PAC pretreatment because of the export of fines. On the contrary, the ceramic membranes were not significantly impacted by their presence. The analysis of CIP washwaters showed a greater total organic carbon (TOC) content on membranes with a PAC pretreatment while no similar conclusion could be made for inorganic foulants. PMID:27399788

  14. Impact of PAC Fines in Fouling of Polymeric and Ceramic Low-Pressure Membranes for Drinking Water Treatment.

    PubMed

    Oligny, Laurent; Bérubé, Pierre R; Barbeau, Benoit

    2016-07-07

    This study assessed the issue of membrane fouling in a Hybrid Membrane Process (HMP) due to the export of powdered activated carbon (PAC) fines from a pretreatment contactor. Two parallel pilot-scale ceramic and polymeric membranes were studied. Reversible and irreversible foulings were measured following three cleaning procedures: Physical backwashing (BW), chemically enhanced backwashing (CEB) and Clean-in-Place (CIP). The impacts on fouling of membrane type, operation flux increase and the presence/absence of the PAC pretreatment were investigated. Membranes without pretreatment were operated in parallel as a control. In addition, CIP washwaters samples were analyzed to measure organic and inorganic foulants removed from the membranes. It was observed that for the polymeric membranes, fouling generally increased with the presence of the PAC pretreatment because of the export of fines. On the contrary, the ceramic membranes were not significantly impacted by their presence. The analysis of CIP washwaters showed a greater total organic carbon (TOC) content on membranes with a PAC pretreatment while no similar conclusion could be made for inorganic foulants.

  15. Preparation and Characterization of Graphene Oxide Paper

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dikin,D.; Stankovich, S.; Zimney, E.

    2007-01-01

    Free-standing paper-like or foil-like materials are an integral part of our technological society. Their uses include protective layers, chemical filters, components of electrical batteries or supercapacitors, adhesive layers, electronic or optoelectronic components, and molecular storage. Inorganic 'paper-like' materials based on nanoscale components such as exfoliated vermiculite or mica platelets have been intensively studied and commercialized as protective coatings, high-temperature binders, dielectric barriers and gas-impermeable membranes. Carbon-based flexible graphite foils composed of stacked platelets of expanded graphite have long been used in packing and gasketing applications because of their chemical resistivity against most media, superior sealability over a wide temperature range,more » and impermeability to fluids. The discovery of carbon nanotubes brought about bucky paper, which displays excellent mechanical and electrical properties that make it potentially suitable for fuel cell and structural composite applications. Here we report the preparation and characterization of graphene oxide paper, a free-standing carbon-based membrane material made by flow-directed assembly of individual graphene oxide sheets. This new material outperforms many other paper-like materials in stiffness and strength. Its combination of macroscopic flexibility and stiffness is a result of a unique interlocking-tile arrangement of the nanoscale graphene oxide sheets.« less

  16. Preparation and characterization of graphene oxide paper.

    PubMed

    Dikin, Dmitriy A; Stankovich, Sasha; Zimney, Eric J; Piner, Richard D; Dommett, Geoffrey H B; Evmenenko, Guennadi; Nguyen, SonBinh T; Ruoff, Rodney S

    2007-07-26

    Free-standing paper-like or foil-like materials are an integral part of our technological society. Their uses include protective layers, chemical filters, components of electrical batteries or supercapacitors, adhesive layers, electronic or optoelectronic components, and molecular storage. Inorganic 'paper-like' materials based on nanoscale components such as exfoliated vermiculite or mica platelets have been intensively studied and commercialized as protective coatings, high-temperature binders, dielectric barriers and gas-impermeable membranes. Carbon-based flexible graphite foils composed of stacked platelets of expanded graphite have long been used in packing and gasketing applications because of their chemical resistivity against most media, superior sealability over a wide temperature range, and impermeability to fluids. The discovery of carbon nanotubes brought about bucky paper, which displays excellent mechanical and electrical properties that make it potentially suitable for fuel cell and structural composite applications. Here we report the preparation and characterization of graphene oxide paper, a free-standing carbon-based membrane material made by flow-directed assembly of individual graphene oxide sheets. This new material outperforms many other paper-like materials in stiffness and strength. Its combination of macroscopic flexibility and stiffness is a result of a unique interlocking-tile arrangement of the nanoscale graphene oxide sheets.

  17. Nitrogen recovery from wastewater using gas-permeable membranes: Impact of inorganic carbon content and natural organic matter.

    PubMed

    Daguerre-Martini, S; Vanotti, M B; Rodriguez-Pastor, M; Rosal, A; Moral, R

    2018-06-15

    Gas-permeable membranes coupled with low-rate aeration is useful to recover ammonia (NH 4 + ) from livestock effluents. In this study, the role of inorganic carbon (bicarbonate, HCO 3 - ) to enhance the N recovery process was evaluated using synthetic effluents with various NH 4 + to HCO 3 - molar ratios of 0.5, 1.0, 1.5 and 2.0. The study also evaluated the effect of increased organic matter on the NH 4 + recovery using humic acids (3000-6000 mg L -1 ), and the N recovery from high-strength swine manure. The release of hydroxide from the HCO 3 - with aeration increased the wastewater pH and promoted gaseous ammonia formation and membrane uptake. At the same time, the recovery of gaseous ammonia (NH 3 ) through the membrane acidified the wastewater. Therefore, an abundant inorganic carbon supply in balance with the NH 4 + is needed for a successful operation of the technology. NH 4 + removal efficiencies >96% were obtained with NH 4 + to HCO 3 - ratios ≤1. However, higher molar ratios inhibited the N recovery process resulting in lower efficiencies (<65%). Fortunately, most swine manures contain ample supply of endogenous inorganic carbon and the process can be used to more economically recover the ammonia using the natural inorganic carbon instead of expensive alkali chemicals. In 4 days, the recovered NH 4 + from swine manure contained 48,000 mg L -1 . Finally, it was found the process was not inhibited by the increasing levels of organic matter in the wastewater evaluated. Published by Elsevier Ltd.

  18. From Chemical Gardens to Fuel Cells: Generation of Electrical Potential and Current Across Self-Assembling Iron Mineral Membranes.

    PubMed

    Barge, Laura M; Abedian, Yeghegis; Russell, Michael J; Doloboff, Ivria J; Cartwright, Julyan H E; Kidd, Richard D; Kanik, Isik

    2015-07-06

    We examine the electrochemical gradients that form across chemical garden membranes and investigate how self-assembling, out-of-equilibrium inorganic precipitates-mimicking in some ways those generated in far-from-equilibrium natural systems-can generate electrochemical energy. Measurements of electrical potential and current were made across membranes precipitated both by injection and solution interface methods in iron-sulfide and iron-hydroxide reaction systems. The battery-like nature of chemical gardens was demonstrated by linking multiple experiments in series which produced sufficient electrical energy to light an external light-emitting diode (LED). This work paves the way for determining relevant properties of geological precipitates that may have played a role in hydrothermal redox chemistry at the origin of life, and materials applications that utilize the electrochemical properties of self-organizing chemical systems. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Effects of suspended titanium dioxide nanoparticles on cake layer formation in submerged membrane bioreactor.

    PubMed

    Zhou, Lijie; Zhang, Zhiqiang; Xia, Siqing; Jiang, Wei; Ye, Biao; Xu, Xiaoyin; Gu, Zaoli; Guo, Wenshan; Ngo, Huu-Hao; Meng, Xiangzhou; Fan, Jinhong; Zhao, Jianfu

    2014-01-01

    Effects of the suspended titanium dioxide nanoparticles (TiO2 NPs, 50 mg/L) on the cake layer formation in a submerged MBR were systematically investigated. With nanometer sizes, TiO2 NPs were found to aggravate membrane pore blocking but postpone cake layer fouling. TiO2 NPs showed obvious effects on the structure and the distribution of the organic and the inorganic compounds in cake layer. Concentrations of fatty acids and cholesterol in the cake layer increased due to the acute response of bacteria to the toxicity of TiO2 NPs. Line-analysis and dot map of energy-dispersive X-ray were also carried out. Since TiO2 NPs inhibited the interactions between the inorganic and the organic compounds, the inorganic compounds (especially SiO2) were prevented from depositing onto the membrane surface. Thus, the postponed cake layer fouling was due to the changing features of the complexes on the membrane surface caused by TiO2 NPs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Breakthrough and future: nanoscale controls of compositions, morphologies, and mesochannel orientations toward advanced mesoporous materials.

    PubMed

    Yamauchi, Yusuke; Suzuki, Norihiro; Radhakrishnan, Logudurai; Wang, Liang

    2009-01-01

    Currently, ordered mesoporous materials prepared through the self-assembly of surfactants have attracted growing interests owing to their special properties, including uniform mesopores and a high specific surface area. Here we focus on fine controls of compositions, morphologies, mesochannel orientations which are important factors for design of mesoporous materials with new functionalities. This Review describes our recent progress toward advanced mesoporous materials. Mesoporous materials now include a variety of inorganic-based materials, for example, transition-metal oxides, carbons, inorganic-organic hybrid materials, polymers, and even metals. Mesoporous metals with metallic frameworks can be produced by using surfactant-based synthesis with electrochemical methods. Owing to their metallic frameworks, mesoporous metals with high electroconductivity and high surface areas hold promise for a wide range of potential applications, such as electronic devices, magnetic recording media, and metal catalysts. Fabrication of mesoporous materials with controllable morphologies is also one of the main subjects in this rapidly developing research field. Mesoporous materials in the form of films, spheres, fibers, and tubes have been obtained by various synthetic processes such as evaporation-mediated direct templating (EDIT), spray-dried techniques, and collaboration with hard-templates such as porous anodic alumina and polymer membranes. Furthermore, we have developed several approaches for orientation controls of 1D mesochannels. The macroscopic-scale controls of mesochannels are important for innovative applications such as molecular-scale devices and electrodes with enhanced diffusions of guest species. Copyright 2009 The Japan Chemical Journal Forum and Wiley Periodicals, Inc.

  1. Catalyzed CO.sub.2-transport membrane on high surface area inorganic support

    DOEpatents

    Liu, Wei

    2014-05-06

    Disclosed are membranes and methods for making the same, which membranes provide improved permeability, stability, and cost-effective manufacturability, for separating CO.sub.2 from gas streams such as flue gas streams. High CO.sub.2 permeation flux is achieved by immobilizing an ultra-thin, optionally catalyzed fluid layer onto a meso-porous modification layer on a thin, porous inorganic substrate such as a porous metallic substrate. The CO.sub.2-selective liquid fluid blocks non-selective pores, and allows for selective absorption of CO.sub.2 from gas mixtures such as flue gas mixtures and subsequent transport to the permeation side of the membrane. Carbon dioxide permeance levels are in the order of 1.0.times.10.sup.-6 mol/(m.sup.2sPa) or better. Methods for making such membranes allow commercial scale membrane manufacturing at highly cost-effective rates when compared to conventional commercial-scale CO.sub.2 separation processes and equipment for the same and such membranes are operable on an industrial use scale.

  2. Fabricating porous materials using interpenetrating inorganic-organic composite gels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Seo, Dong-Kyun; Volosin, Alex

    Porous materials are fabricated using interpenetrating inorganic-organic composite gels. A mixture or precursor solution including an inorganic gel precursor, an organic polymer gel precursor, and a solvent is treated to form an inorganic wet gel including the organic polymer gel precursor and the solvent. The inorganic wet gel is then treated to form a composite wet gel including an organic polymer network in the body of the inorganic wet gel, producing an interpenetrating inorganic-organic composite gel. The composite wet gel is dried to form a composite material including the organic polymer network and an inorganic network component. The composite materialmore » can be treated further to form a porous composite material, a porous polymer or polymer composite, a porous metal oxide, and other porous materials.« less

  3. Effectiveness of inorganic membrane mixture of natural zeolite and portland white cement in purifying of peat water based on turbidity parameter

    NASA Astrophysics Data System (ADS)

    Elfiana; Fuadi, A.; Diana, S.

    2018-04-01

    Peat water is water surface that brownish red colour caused by the contained constituents. Solving the peat watercolor problem requires special attention considering the quantity of peat water and suitable to be used to meet the daily needs. This study aims to know the inorganic membrane capability of mix nature zeolite and white Portland cement to purifying the peat water based on turbidity parameter. The study was conducted by varying the composition of nature zeolite (Za) and white Portland cement (Sp) in the ratio of Za: Sp is (25%:75%; 50%:50%; 75%:25%) with zeolite condition activated using HCl 2M and nonactivated zeolite treatments. The result of the characteristic test on membrane morphology using SEM (Scanning Electron Microscope) showed that the pore surface size of the membrane is 2 μm that could classified in microfiltration membrane an organic type. The characteristic test showed also resulted in the density of 0.77 to 0.86 gr/cm3, porosity 26.22% to 35.93%, and permeability 2736.19 to 8428.15. While the water retention capacity is in range of 30.64% to 46.46%, The result of inorganic membrane application on peat water showed turbidity of peat water decreased 94.17%, from 10.3 NTU to 0.6 NTU.

  4. Flow-through pretreatment of lignocellulosic biomass with inorganic nanoporous membranes

    DOEpatents

    Bhave, Ramesh R.; Lynd, Lee; Shao, Xiongjun

    2018-04-03

    A process for the pretreatment of lignocellulosic biomass is provided. The process generally includes flowing water through a pretreatment reactor containing a bed of particulate ligno-cellulosic biomass to produce a pressurized, high-temperature hydrolyzate exit stream, separating solubilized compounds from the hydrolyzate exit stream using an inorganic nanoporous membrane element, fractionating the retentate enriched in solubilized organic components and recycling the permeate to the pretreatment reactor. The pretreatment process provides solubilized organics in concentrated form for the subsequent conversion into biofuels and other chemicals.

  5. A proton-exchange membrane prepared by the radiation grafting of styrene and silica into polytetrafluoroethylene films

    NASA Astrophysics Data System (ADS)

    Yu, Hongyan; Shi, Jianheng; Zeng, Xinmiao; Bao, Mao; Zhao, Xinqing

    2009-07-01

    A polytetrafluoroethylene (PTFE) based organic-inorganic hybrid proton-exchange membrane was prepared from simultaneous radiation grafting of styrene (St) into porous PTFE membrane with the in situ sol-gel reaction of tetraethoxysilane (TEOS) followed by sulfonation in fuming sulfonic acid. The effect of radiation on the sol-gel reaction was studied. The results show that radiation promotes the sol-gel reaction with the help of St at room temperature. Incorporated silica gel helps to produce higher degree of grafting (DOG). SEM analysis was conducted to confirm that the inorganic silicon oxide was introduced to produce hybrid membrane in this work. The proton conductivity of membrane evaluated using electrochemical impedance spectroscopy is much higher (14.3×10 -2 S cm -1) than that of Nafion ® 117 at temperature of 80 °C with acceptable water uptake 51 wt%.

  6. New High-Temperature Membranes Developed for Proton Exchange Membrane Fuel Cells

    NASA Technical Reports Server (NTRS)

    Kinder, James D.

    2004-01-01

    Fuel cells are receiving a considerable amount of attention for potential use in a variety of areas, including the automotive industry, commercial power generation, and personal electronics. Research at the NASA Glenn Research Center has focused on the development of fuel cells for use in aerospace power systems for aircraft, unmanned air vehicles, and space transportation systems. These applications require fuel cells with higher power densities and better durability than what is required for nonaerospace uses. In addition, membrane cost is a concern for any fuel cell application. The most widely used membrane materials for proton exchange membrane (PEM) fuel cells are based on sulfonated perfluorinated polyethers, typically Nafion 117, Flemion, or Aciplex. However, these polymers are costly and do not function well at temperatures above 80 C. At higher temperatures, conventional membrane materials dry out and lose their ability to conduct protons, essential for the operation of the fuel cell. Increasing the operating temperature of PEM fuel cells from 80 to 120 C would significantly increase their power densities and enhance their durability by reducing the susceptibility of the electrode catalysts to carbon monoxide poisoning. Glenn's Polymers Branch has focused on developing new, low-cost membranes that can operate at these higher temperatures. A new series of organically modified siloxane (ORMOSIL) polymers were synthesized for use as membrane materials in a high-temperature PEM fuel cell. These polymers have an organic portion that can allow protons to transport through the polymer film and a cross-linked silica network that gives the polymers dimensional stability. These flexible xerogel polymer films are thermally stable, with decomposition onset as high as 380 C. Two types of proton-conducting ORMOSIL films have been produced: (1) NASA-A, which can coordinate many highly acid inorganic salts that facilitate proton conduction and (2) NASA-B, which has been produced and which incorporates strongly acidic (proton donating) functional groups into the polymer backbone. Both of these polymer films have demonstrated significantly higher proton conductivity than Nafion at elevated temperatures and low relative humidities. An added advantage is that these polymers are very inexpensive to produce because their starting materials are commodity chemicals that are commercially available in large volumes.

  7. Membrane Bioreactor (MBR) Technology for Wastewater Treatment and Reclamation: Membrane Fouling

    PubMed Central

    Iorhemen, Oliver Terna; Hamza, Rania Ahmed; Tay, Joo Hwa

    2016-01-01

    The membrane bioreactor (MBR) has emerged as an efficient compact technology for municipal and industrial wastewater treatment. The major drawback impeding wider application of MBRs is membrane fouling, which significantly reduces membrane performance and lifespan, resulting in a significant increase in maintenance and operating costs. Finding sustainable membrane fouling mitigation strategies in MBRs has been one of the main concerns over the last two decades. This paper provides an overview of membrane fouling and studies conducted to identify mitigating strategies for fouling in MBRs. Classes of foulants, including biofoulants, organic foulants and inorganic foulants, as well as factors influencing membrane fouling are outlined. Recent research attempts on fouling control, including addition of coagulants and adsorbents, combination of aerobic granulation with MBRs, introduction of granular materials with air scouring in the MBR tank, and quorum quenching are presented. The addition of coagulants and adsorbents shows a significant membrane fouling reduction, but further research is needed to establish optimum dosages of the various coagulants/adsorbents. Similarly, the integration of aerobic granulation with MBRs, which targets biofoulants and organic foulants, shows outstanding filtration performance and a significant reduction in fouling rate, as well as excellent nutrients removal. However, further research is needed on the enhancement of long-term granule integrity. Quorum quenching also offers a strong potential for fouling control, but pilot-scale testing is required to explore the feasibility of full-scale application. PMID:27314394

  8. Polyphosphazene semipermeable membranes

    DOEpatents

    Allen, Charles A.; McCaffrey, Robert R.; Cummings, Daniel G.; Grey, Alan E.; Jessup, Janine S.; McAtee, Richard E.

    1988-01-01

    A semipermeable, inorganic membrane is disclosed; the membrane is prepared from a phosphazene polymer and, by the selective substitution of the constituent groups bound to the phosphorous in the polymer structure, the selective passage of fluid from a feedstream can be controlled. Resistance to high temperatures and harsh chemical environments is observed in the use of the phosphazene polymers as semipermeable membranes.

  9. USEPA/WSWRD MEMBRANE RESEARCH

    EPA Science Inventory

    The USEPA has been very active in membrane research. The following areas are currently being investigated: in-house fouling research, Information Collection Rule (ICR) treatment studies, inorganic scaling modeling, Environmental Technology Verification (ETV) program implementati...

  10. Gas Transport Selectivity of Ultrathin, Nanoporous, Inorganic Membranes Made from Block Copolymer Templates

    DOE PAGES

    Greil, Stefanie; Rahman, Atikur; Liu, Mingzhao; ...

    2017-10-10

    Here, we report the fabrication of ultrathin, nanoporous silicon nitride membranes made from templates of regular, nanoscale features in self-assembled block copolymer thin films. The inorganic membranes feature thicknesses less than 50 nm and volume porosities over 30%, with straight-through pores that offer high throughout for gas transport and separation applications. As fabricated, the pores are uniformly around 20 nm in diameter, but they can be controllably and continuously tuned to single-digit nanometer dimensions by atomic layer deposition of conformal coatings. A deviation from expected Knudsen diffusion is revealed for transport characteristics of saturated vapors of organic solvents across themore » membrane, which becomes more significant for membranes of smaller pores. We attribute this to capillary condensation of saturated vapors within membrane pores, which reduces membrane throughput by over 1 order of magnitude but significantly improves the membrane’s selectivity. Between vapors of acetone and ethyl acetate, we measure selectivities as high as 7:1 at ambient pressure and temperature, 4 times more than the Knudsen selectivity.« less

  11. Oxidative coupling of methane using inorganic membrane reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ma, Y.H.; Moser, W.R.; Dixon, A.G.

    1995-12-31

    The goal of this research is to improve the oxidative coupling of methane in a catalytic inorganic membrane reactor. A specific target is to achieve conversion of methane to C{sub 2} hydrocarbons at very high selectivity and relatively higher yields than in fixed bed reactors by controlling the oxygen supply through the membrane. A membrane reactor has the advantage of precisely controlling the rate of delivery of oxygen to the catalyst. This facility permits balancing the rate of oxidation and reduction of the catalyst. In addition, membrane reactors minimize the concentration of gas phase oxygen thus reducing non selective gasmore » phase reactions, which are believed to be a main route for formation of CO{sub x} products. Such gas phase reactions are a cause for decreased selectivity in oxidative coupling of methane in conventional flow reactors. Membrane reactors could also produce higher product yields by providing better distribution of the reactant gases over the catalyst than the conventional plug flow reactors. Modeling work which aimed at predicting the observed experimental trends in porous membrane reactors was also undertaken in this research program.« less

  12. Gas Transport Selectivity of Ultrathin, Nanoporous, Inorganic Membranes Made from Block Copolymer Templates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Greil, Stefanie; Rahman, Atikur; Liu, Mingzhao

    Here, we report the fabrication of ultrathin, nanoporous silicon nitride membranes made from templates of regular, nanoscale features in self-assembled block copolymer thin films. The inorganic membranes feature thicknesses less than 50 nm and volume porosities over 30%, with straight-through pores that offer high throughout for gas transport and separation applications. As fabricated, the pores are uniformly around 20 nm in diameter, but they can be controllably and continuously tuned to single-digit nanometer dimensions by atomic layer deposition of conformal coatings. A deviation from expected Knudsen diffusion is revealed for transport characteristics of saturated vapors of organic solvents across themore » membrane, which becomes more significant for membranes of smaller pores. We attribute this to capillary condensation of saturated vapors within membrane pores, which reduces membrane throughput by over 1 order of magnitude but significantly improves the membrane’s selectivity. Between vapors of acetone and ethyl acetate, we measure selectivities as high as 7:1 at ambient pressure and temperature, 4 times more than the Knudsen selectivity.« less

  13. The Drive to Life on Wet and Icy Worlds

    PubMed Central

    Barge, Laura M.; Bhartia, Rohit; Bocanegra, Dylan; Bracher, Paul J.; Branscomb, Elbert; Kidd, Richard; McGlynn, Shawn; Meier, David H.; Nitschke, Wolfgang; Shibuya, Takazo; Vance, Steve; White, Lauren; Kanik, Isik

    2014-01-01

    Abstract This paper presents a reformulation of the submarine alkaline hydrothermal theory for the emergence of life in response to recent experimental findings. The theory views life, like other self-organizing systems in the Universe, as an inevitable outcome of particular disequilibria. In this case, the disequilibria were two: (1) in redox potential, between hydrogen plus methane with the circuit-completing electron acceptors such as nitrite, nitrate, ferric iron, and carbon dioxide, and (2) in pH gradient between an acidulous external ocean and an alkaline hydrothermal fluid. Both CO2 and CH4 were equally the ultimate sources of organic carbon, and the metal sulfides and oxyhydroxides acted as protoenzymatic catalysts. The realization, now 50 years old, that membrane-spanning gradients, rather than organic intermediates, play a vital role in life's operations calls into question the idea of “prebiotic chemistry.” It informs our own suggestion that experimentation should look to the kind of nanoengines that must have been the precursors to molecular motors—such as pyrophosphate synthetase and the like driven by these gradients—that make life work. It is these putative free energy or disequilibria converters, presumably constructed from minerals comprising the earliest inorganic membranes, that, as obstacles to vectorial ionic flows, present themselves as the candidates for future experiments. Key Words: Methanotrophy—Origin of life. Astrobiology 14, 308–343. The fixation of inorganic carbon into organic material (autotrophy) is a prerequisite for life and sets the starting point of biological evolution. (Fuchs, 2011) Further significant progress with the tightly membrane-bound H+-PPase family should lead to an increased insight into basic requirements for the biological transport of protons through membranes and its coupling to phosphorylation. (Baltscheffsky et al., 1999) PMID:24697642

  14. The drive to life on wet and icy worlds.

    PubMed

    Russell, Michael J; Barge, Laura M; Bhartia, Rohit; Bocanegra, Dylan; Bracher, Paul J; Branscomb, Elbert; Kidd, Richard; McGlynn, Shawn; Meier, David H; Nitschke, Wolfgang; Shibuya, Takazo; Vance, Steve; White, Lauren; Kanik, Isik

    2014-04-01

    This paper presents a reformulation of the submarine alkaline hydrothermal theory for the emergence of life in response to recent experimental findings. The theory views life, like other self-organizing systems in the Universe, as an inevitable outcome of particular disequilibria. In this case, the disequilibria were two: (1) in redox potential, between hydrogen plus methane with the circuit-completing electron acceptors such as nitrite, nitrate, ferric iron, and carbon dioxide, and (2) in pH gradient between an acidulous external ocean and an alkaline hydrothermal fluid. Both CO2 and CH4 were equally the ultimate sources of organic carbon, and the metal sulfides and oxyhydroxides acted as protoenzymatic catalysts. The realization, now 50 years old, that membrane-spanning gradients, rather than organic intermediates, play a vital role in life's operations calls into question the idea of "prebiotic chemistry." It informs our own suggestion that experimentation should look to the kind of nanoengines that must have been the precursors to molecular motors-such as pyrophosphate synthetase and the like driven by these gradients-that make life work. It is these putative free energy or disequilibria converters, presumably constructed from minerals comprising the earliest inorganic membranes, that, as obstacles to vectorial ionic flows, present themselves as the candidates for future experiments. Key Words: Methanotrophy-Origin of life. Astrobiology 14, 308-343. The fixation of inorganic carbon into organic material (autotrophy) is a prerequisite for life and sets the starting point of biological evolution. (Fuchs, 2011 ) Further significant progress with the tightly membrane-bound H(+)-PPase family should lead to an increased insight into basic requirements for the biological transport of protons through membranes and its coupling to phosphorylation. (Baltscheffsky et al., 1999 ).

  15. A flexible all-inorganic fuel cell membrane with conductivity above Nafion, and durable operation at 150 °C

    NASA Astrophysics Data System (ADS)

    Ansari, Y.; Tucker, T. G.; Huang, W.; Klein, I. S.; Lee, S.-Y.; Yarger, J. L.; Angell, C. A.

    2016-01-01

    The search for fuel cell membranes has focused on carbon backbone polymers, among which Nafion seems to best survive the most severe of the degradation mechanisms - attack by peroxide radicals. Less attention has been given to inorganic membranes because of their generally inflexible nature and lower conductivity, though some SiO2-Nafion composites have shown improved properties. Nafion dominates, despite needing hydration, which then restricts operation to below 100 °C (so CO poisoning problems persist). Described herein is a low cost, flexible, and all-inorganic fiberglass reinforced gel membrane with conductivity exceeding that of Nafion at any temperature above 60 °C. Using Teflon fuel cells, maximum currents > 1 Acm-2 and OCV of 1.03 V at 150 °C are demonstrated. No detectable loss of cell potential was observed over 24 h during 50 mAcm-2 constant current operation at 120 °C while, at 150 °C and maximum power, the degradation rate is intermediate among other high conductivity H3PO4-PBI type membranes. The structure of the membrane is deduced, mainly from 29Si solid state-NMR. The -115 ppm resonance, which is extreme for Q4 Si(O) structures, identifies a zeolite-like SiO2 network, which is ;floppy;. 31P and 1H NMR establish nano-permeating H3PO4 as the source of the exceptional conductivity.

  16. Direct membrane-carbonation photobioreactor producing photoautotrophic biomass via carbon dioxide transfer and nutrient removal.

    PubMed

    Kim, Hyun-Woo; Cheng, Jing; Rittmann, Bruce E

    2016-03-01

    An advanced-material photobioreactor, the direct membrane-carbonation photobioreactor (DMCPBR), was tested to investigate the impact of directly submerging a membrane carbonation (MC) module of hollow-fiber membranes inside the photobioreactor. Results demonstrate that the DMCPBR utilized over 90% of the supplied CO2 by matching the CO2 flux to the C demand of photoautotrophic biomass growth. The surface area of the submerged MC module was the key to control CO2 delivery and biomass productivity. Tracking the fate of supplied CO2 explained how the DMCPBR reduced loss of gaseous CO2 while matching the inorganic carbon (IC) demand to its supply. Accurate fate analysis required that the biomass-associated C include soluble microbial products as a sink for captured CO2. With the CO2 supply matched to the photosynthetic demand, light attenuation limited the rate microalgal photosynthesis. The DMCPBR presents an opportunity to improve CO2-deliver efficiency and make microalgae a more effective strategy for C-neutral resource recovery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Design and fabrication of zeolite macro- and micromembranes

    NASA Astrophysics Data System (ADS)

    Chau, Lik Hang Joseph

    2001-07-01

    The chemical nature of the support surface influences zeolite nucleation, crystal growth and elm adhesion. It had been demonstrated that chemical modification of support surface can significantly alter the zeolite film and has a good potential for large-scale applications for zeolite membrane production. The incorporation of titanium and vanadium metal ions into the structural framework of MFI zeolite imparts the material with catalytic properties. The effects of silica and metal (i.e., Ti and V) content, template concentration and temperature on the zeolite membrane growth and morphology were investigated. Single-gas permeation experiments were conducted for noble gases (He and Ar), inorganic gases (H2, N2, SF6) and hydrocarbons (methane, n-C4, i-C4) to determine the separation performance of these membranes. Using a new fabrication method based on microelectronic fabrication and zeolite thin film technologies, complex microchannel geometry and network (<5 mum), as well as zeolite arrays (<10 mum) were successfully fabricated onto highly orientated supported zeolite films. The zeolite micropatterns were stable even after repeated thermal cycling between 303 K and 873 K for prolonged periods of time. This work also demonstrates that zeolites (i.e., Sil-1, ZSM-5 and TS-1) can be employed as catalyst, membrane or structural materials in miniature chemical devices. Traditional semiconductor fabrication technology was employed in micromachining the device architecture. Four strategies for the manufacture of zeolite catalytic microreactors were discussed: zeolite powder coating, uniform zeolite film growth, localized zeolite growth, and etching of zeolite-silicon composite film growth inhibitors. Silicalite-1 was also prepared as free-standing membrane for zeolite membrane microseparators.

  18. Thin film composition with biological substance and method of making

    DOEpatents

    Campbell, Allison A.; Song, Lin

    1999-01-01

    The invention provides a thin-film composition comprising an underlying substrate of a first material including a plurality of attachment sites; a plurality of functional groups chemically attached to the attachment sites of the underlying substrate; and a thin film of a second material deposited onto the attachment sites of the underlying substrate, and a biologically active substance deposited with the thin-film. Preferably the functional groups are attached to a self assembling monolayer attached to the underlying substrate. Preferred functional groups attached to the underlying substrate are chosen from the group consisting of carboxylates, sulfonates, phosphates, optionally substituted, linear or cyclo, alkyl, alkene, alkyne, aryl, alkylaryl, amine, hydroxyl, thiol, silyl, phosphoryl, cyano, metallocenyl, carbonyl, and polyphosphate. Preferred materials for the underlying substrate are selected from the group consisting of a metal, a metal alloy, a plastic, a polymer, a proteic film, a membrane, a glass or a ceramic. The second material is selected from the group consisting of inorganic crystalline structures, inorganic amorphus structures, organic crystalline structures, and organic amorphus structures. Preferred second materials are phosphates, especially calcium phosphates and most particularly calcium apatite. The biologically active molecule is a protein, peptide, DNA segment, RNA segment, nucleotide, polynucleotide, nucleoside, antibiotic, antimicrobal, radioisotope, chelated radioisotope, chelated metal, metal salt, anti-inflamatory, steriod, nonsteriod anti-inflammatory, analgesic, antihistamine, receptor binding agent, or chemotherapeutic agent, or other biologically active material. Preferably the biologically active molecule is an osteogenic factor the compositions listed above.

  19. AIEgens-Functionalized Inorganic-Organic Hybrid Materials: Fabrications and Applications.

    PubMed

    Li, Dongdong; Yu, Jihong

    2016-12-01

    Inorganic materials functionalized with organic fluorescent molecules combine advantages of them both, showing potential applications in biomedicine, chemosensors, light-emitting, and so on. However, when more traditional organic dyes are doped into the inorganic materials, the emission of resulting hybrid materials may be quenched, which is not conducive to the efficiency and sensitivity of detection. In contrast to the aggregation-caused quenching (ACQ) system, the aggregation-induced emission luminogens (AIEgens) with high solid quantum efficiency, offer new potential for developing highly efficient inorganic-organic hybrid luminescent materials. So far, many AIEgens have been incorporated into inorganic materials through either physical doping caused by aggregation induced emission (AIE) or chemical bonding (e.g., covalent bonding, ionic bonding, and coordination bonding) caused by bonding induced emission (BIE) strategy. The hybrid materials exhibit excellent photoactive properties due to the intramolecular motion of AIEgens is restricted by inorganic matrix. Recent advances in the fabrication of AIEgens-functionalized inorganic-organic hybrid materials and their applications in biomedicine, chemical sensing, and solid-state light emitting are presented. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. The cytotoxic effects of titanium oxide and zinc oxide nanoparticles oh Human Cervical Adenocarcinoma cell membranes

    NASA Astrophysics Data System (ADS)

    Mironava, Tatsiana; Applebaum, Ariella; Applebaum, Eliana; Guterman, Shoshana; Applebaum, Kayla; Grossman, Daniel; Gordon, Chris; Brink, Peter; Wang, H. Z.; Rafailovich, Miriam

    2013-03-01

    The importance of titanium dioxide (TiO2) and zinc oxide (ZnO), inorganic metal oxides nanoparticles (NPs) stems from their ubiquitous applications in personal care products, solar cells and food whitening agents. Hence, these NPs come in direct contact with the skin, digestive tracts and are absorbed into human tissues. Currently, TiO2 and ZnO are considered safe commercial ingredients by the material safety data sheets with no reported evidence of carcinogenicity or ecotoxicity, and do not classify either NP as a toxic substance. This study examined the direct effects of TiO2 and ZnO on HeLa cells, a human cervical adenocarcinonma cell line, and their membrane mechanics. The whole cell patch-clamp technique was used in addition to immunohistochemistry staining, TEM and atomic force microscopy (AFM). Additionally, we examined the effects of dexamethasone (DXM), a glucocorticoid steroid known to have an effect on cell membrane mechanics. Overall, TiO2 and ZnO seemed to have an adverse effect on cell membrane mechanics by effecting cell proliferation, altering cellular structure, decreasing cell-cell adhesion, activating existing ion channels, increasing membrane permeability, and possibly disrupting cell signaling.

  1. Determination of Cd2+ in aqueous solution using polyindole-Ce(IV) vanadophosphate conductive nanocomposite ion-selective membrane electrode

    NASA Astrophysics Data System (ADS)

    Khan, Asif Ali; Quasim Khan, Mohd; Hussain, Rizwan

    2017-09-01

    In the present study an organic-inorganic nanocomposite ion exchanger Polyindole-Ce(IV) vanadophosphate (PIn-CVP) was synthesized via sol-gel process showing excellent ion exchange capacity (IEC‒1.90 meqg-1). The material was characterized by SEM, TEM, XRD, FTIR, and TGA. A heterogeneous ion exchange membrane of PIn-CVP (IEC‒0.90 meqg-1) was also prepared by solution casting method. PIn-CVP shows high electrical conductivity (5.5  ×  10-2 S cm-1) and it is stable up to 120 °C under ambient conditions. Cd2+ selective membrane electrode was fabricated and its linear working range (3.98  ×  10-7 M to 1.0  ×  10-1 M), response time (25 s), Nerstian slope 25.00 mV dec-1 and working pH range (4-7) were calculated. It was employed as an indicator electrode in the potentiometric titration of Cd2+.

  2. A Structural and Molecular Approach for the Study Biomarkers

    NASA Technical Reports Server (NTRS)

    Thomas-Keprta, Kathie; Vali, Hojatollah; Sears, S. Kelly; Roh, Yul

    2001-01-01

    Investigation of the nucleation and growth of crystals in both abiotic and biotic systems is critical to seemingly diverse disciplines of geology, biology, environmental science, and astrobiology. While there are abundant studies devoted to the determination of the structure and composition of inorganic crystals, as well as to the development of thermodynamic and kinetic models, it is only recently that research efforts have been directed towards understanding mineralization in biological systems (i.e., biomineralization). Biomineralization refers to the processes by which living organisms form inorganic solids. Studies of the processes of biomineralization under low temperature aqueous conditions have focused primarily on magnetite forming bacteria and shell forming marine organisms. Many of the biological building materials consist of inorganic minerals (calcium carbonate, calcium phosphate, silica or iron oxide) intricately combined with organic polymers (like proteins). More recently, efforts have been undertaken to explore the nature of biological activities in ancient rocks. In the absence of well-preserved microorganisms or genetic material required for the polmerase chain reaction (PCR) method in molecular phylogenetic studies, using biominerals as biomarkers offers an alternative approach for the recognition of biogenic activity in both terrestrial and extraterrestrial environments. The primary driving force in biomineralization is the interaction between organic and inorganic phases. Thus, the investigation of the ultrastructure and the nature of reactions at the molecular level occurring at the interface between inorganic and organic phases is essential to understanding the processes leading to the nucleation and growth of crystals. It is recognized that crystal surfaces can serve as the substrate for the organization of organic molecules that lead to the formation of polymers and other complex organic molecules, and in discussions of the origins of life, is referred to as organic synthesis on mineral surfaces. Furthermore, it is suggested that the interaction between mineral surfaces and simple organic molecules resulted in the formation of amino acids, RNA, and perhaps other more complex molecules such as proteins. On the other hand, in natural systems, it is recognized that functional groups on cell walls or membranes of microorganisms serve as sites of nucleation and crystallization. The precise replication of biominerals with controlled structure, morphology, size and texture is not confined to higher organisms as it also occurs in primitive prokaryotic cells such as magnetotactic bacteria and cyanobacteria. This suggests that the principal strategies of biomineralization were established early on in the evolutionary history of organisms. It is critical, therefore, to search for common mechanisms within diverse biological systems. One such common factor is the capability for organization and self-assembly. Organic macromolecules such as proteins and lipids can aggregate and polymerize forming membranes or extracellular matrix. At the organic-inorganic interface, several factors such as lattice geometry, polarity, stereochemistry and topography may act in concert to control nucleation and growth of crystals. Although several models have been proposed that discuss the significance of these factors for biomineralization, no comprehensive experimental data are available. In contrast to crystallization in exclusively inorganic systems, the kinetics of reaction and structural relationships between organic and inorganic phases in biominerals or biomimetic material is poorly understood. For example, it is not clear if the concept of epitactic growth (geometrical matching of unit cells at the interface of a secondary crystal growing on a primary crystal) applies to organic-inorganic systems. In contrast to inorganic templates that often have a smooth and rigid surface that promotes epitactic growth, biological substrates are usually rough and result in a large degree of mismatch. It is apparent that factors controlling the reaction at the crystal-matrix interface are strongly dependent upon the nature of the substrate. Therefore, characterization of the assembled organic surface and surface structure of the inorganic phase is crucial to understanding the processes of biomineralization. The focus of our research is the investigation of the processes leading to the nucleation and growth of crystals on both natural and synthetic systems through an interdisciplinary approach that integrates molecular biology, morphology and mineralogy using advanced preparation and analytical techniques. We have studied run-products, particularly magnetite, siderite and other carbonates, that resulted from extracellular biomineralization by extremophiles isolated from a variety of extreme environments ranging from permafrost to hydrothermal vent systems. The results of this study are critical to recognizing biomarkers in terrestrial and extraterrestrial environments.

  3. SUPPORTED LIX-84 LIQUID MEMBRANES FOR METAL ION SEPARATION: A STUDY ON METAL ION SORPTION EQUILIBRIUM AND KINETICS

    EPA Science Inventory

    Supported 2-hydroxy-5-nonyl-acetophenone oxime (LIX-84) liquid membranes have potential applications for the removal (or recovery) of copper ions from waste streams. But, the stability of such a liquid membrane remains the major hurdle for its practical applications. Inorganic su...

  4. Modulation of mitochondrial ion transport by inorganic polyphosphate - essential role in mitochondrial permeability transition pore.

    PubMed

    Baev, Artyom Y; Negoda, Alexander; Abramov, Andrey Y

    2017-02-01

    Inorganic polyphosphate (polyP) is a biopolymer of phosphoanhydride-linked orthophosphate residues. PolyP is involved in multiple cellular processes including mitochondrial metabolism and cell death. We used artificial membranes and isolated mitochondria to investigate the role of the polyP in mitochondrial ion transport and in activation of PTP. Here, we found that polyP can modify ion permeability of de-energised mitochondrial membranes but not artificial membranes. This permeability was selective for Ba 2+ and Ca 2+ but not for other monovalent and bivalent cations and can be blocked by inhibitors of the permeability transition pore - cyclosporine A or ADP. Lower concentrations of polyP modulate calcium dependent permeability transition pore opening. Increase in polyP concentrations and elongation chain length of the polymer causes calcium independent swelling in energized conditions. Physiologically relevant concentrations of inorganic polyP can regulate calcium dependent as well calcium independent mitochondrial permeability transition pore opening. This raises the possibility that cytoplasmic polyP can be an important contributor towards regulation of the cell death.

  5. Critical aspects in the production of periodically ordered mesoporous titania thin films

    NASA Astrophysics Data System (ADS)

    Soler-Illia, Galo J. A. A.; Angelomé, Paula C.; Fuertes, M. Cecilia; Grosso, David; Boissiere, Cedric

    2012-03-01

    Periodically ordered mesoporous titania thin films (MTTF) present a high surface area, controlled porosity in the 2-20 nm pore diameter range and an amorphous or crystalline inorganic framework. These materials are nowadays routinely prepared by combining soft chemistry and supramolecular templating. Photocatalytic transparent coatings and titania-based solar cells are the immediate promising applications. However, a wealth of new prospective uses have emerged on the horizon, such as advanced catalysts, perm-selective membranes, optical materials based on plasmonics and photonics, metamaterials, biomaterials or new magnetic nanocomposites. Current and novel applications rely on the ultimate control of the materials features such as pore size and geometry, surface functionality and wall structure. Even if a certain control of these characteristics has been provided by the methods reported so far, the needs for the next generation of MTTF require a deeper insight in the physical and chemical processes taking place in their preparation and processing. This article presents a critical discussion of these aspects. This discussion is essential to evolve from know-how to sound knowledge, aiming at a rational materials design of these fascinating systems.Periodically ordered mesoporous titania thin films (MTTF) present a high surface area, controlled porosity in the 2-20 nm pore diameter range and an amorphous or crystalline inorganic framework. These materials are nowadays routinely prepared by combining soft chemistry and supramolecular templating. Photocatalytic transparent coatings and titania-based solar cells are the immediate promising applications. However, a wealth of new prospective uses have emerged on the horizon, such as advanced catalysts, perm-selective membranes, optical materials based on plasmonics and photonics, metamaterials, biomaterials or new magnetic nanocomposites. Current and novel applications rely on the ultimate control of the materials features such as pore size and geometry, surface functionality and wall structure. Even if a certain control of these characteristics has been provided by the methods reported so far, the needs for the next generation of MTTF require a deeper insight in the physical and chemical processes taking place in their preparation and processing. This article presents a critical discussion of these aspects. This discussion is essential to evolve from know-how to sound knowledge, aiming at a rational materials design of these fascinating systems. Dedicated to Clément Sanchez, on the first anniversary of his appointment to the Hybrid Materials Chair of the Collège de France.

  6. Organometallic-inorganic hybrid electrodes for lithium-ion batteries

    DOEpatents

    Huang, Qian; Lemmon, John P.; Choi, Daiwon; Cosimbescu, Lelia

    2016-09-13

    Disclosed are embodiments of active materials for organometallic and organometallic-inorganic hybrid electrodes and particularly active materials for organometallic and organometallic-inorganic hybrid cathodes for lithium-ion batteries. In certain embodiments the organometallic material comprises a ferrocene polymer.

  7. Lyotropic liquid crystalline L3 phase silicated nanoporous monolithic composites and their production

    DOEpatents

    McGrath, Kathryn M.; Dabbs, Daniel M.; Aksay, Ilhan A.; Gruner, Sol M.

    2003-10-28

    A mesoporous ceramic material is provided having a pore size diameter in the range of about 10-100 nanometers produced by templating with a ceramic precursor a lyotropic liquid crystalline L.sub.3 phase consisting of a three-dimensional, random, nonperiodic network packing of a multiple connected continuous membrane. A preferred process for producing the inesoporous ceramic material includes producing a template of a lyotropic liquid crystalline L.sub.3 phase by mixing a surfactant, a co-surfactant and hydrochloric acid, coating the template with an inorganic ceramic precursor by adding to the L.sub.3 phase tetramethoxysilane (TMOS) or tetraethoxysilane (TEOS) and then converting the coated template to a ceramic by removing any remaining liquids.

  8. Hybrid Materials Based on the Embedding of Organically Modified Transition Metal Oxoclusters or Polyoxometalates into Polymers for Functional Applications: A Review

    PubMed Central

    Carraro, Mauro; Gross, Silvia

    2014-01-01

    The covalent incorporation of inorganic building blocks into a polymer matrix to obtain stable and robust materials is a widely used concept in the field of organic-inorganic hybrid materials, and encompasses the use of different inorganic systems including (but not limited to) nanoparticles, mono- and polynuclear metal complexes and clusters, polyhedral oligomeric silsesquioxanes (POSS), polyoxometalates (POM), layered inorganic systems, inorganic fibers, and whiskers. In this paper, we will review the use of two particular kinds of structurally well-defined inorganic building blocks, namely transition metals oxoclusters (TMO) and polyoxometalates (POM), to obtain hybrid materials with enhanced functional (e.g., optical, dielectric, magnetic, catalytic) properties. PMID:28788659

  9. Osteoconductive Potential of Barrier NanoSiO2 PLGA Membranes Functionalized by Plasma Enhanced Chemical Vapour Deposition

    PubMed Central

    Terriza, Antonia; Vilches-Pérez, Jose I.; de la Orden, Emilio; Yubero, Francisco; Gonzalez-Caballero, Juan L.; González-Elipe, Agustin R.; Vilches, José; Salido, Mercedes

    2014-01-01

    The possibility of tailoring membrane surfaces with osteoconductive potential, in particular in biodegradable devices, to create modified biomaterials that stimulate osteoblast response should make them more suitable for clinical use, hopefully enhancing bone regeneration. Bioactive inorganic materials, such as silica, have been suggested to improve the bioactivity of synthetic biopolymers. An in vitro study on HOB human osteoblasts was performed to assess biocompatibility and bioactivity of SiO2 functionalized poly(lactide-co-glycolide) (PLGA) membranes, prior to clinical use. A 15 nm SiO2 layer was deposited by plasma enhanced chemical vapour deposition (PECVD), onto a resorbable PLGA membrane. Samples were characterized by X-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy, and infrared spectroscopy (FT-IR). HOB cells were seeded on sterilized test surfaces where cell morphology, spreading, actin cytoskeletal organization, and focal adhesion expression were assessed. As proved by the FT-IR analysis of samples, the deposition by PECVD of the SiO2 onto the PLGA membrane did not alter the composition and other characteristics of the organic membrane. A temporal and spatial reorganization of cytoskeleton and focal adhesions and morphological changes in response to SiO2 nanolayer were identified in our model. The novedous SiO2 deposition method is compatible with the standard sterilization protocols and reveals as a valuable tool to increase bioactivity of resorbable PLGA membranes. PMID:24883304

  10. Filtration performance of microporous ceramic supports.

    PubMed

    Belouatek, Aissa; Ouagued, Abdellah; Belhakem, Mustapha; Addou, Ahmed

    2008-04-24

    The use of inorganic membranes in pollution treatment is actually limited by the cost of such membranes. Advantages of inorganic membranes are their chemical, thermal and pH properties. The purpose of this work was the development of microporous ceramic materials based on clay for liquid waste processing. The supports or ceramic filters having various compositions were prepared and thermally treated at 1100 degrees C. The results show that, at the temperature studied, porosity varied according to the support composition from 12% for the double-layered (ceramic) support to 47% for the activated carbon- filled support with a mean pore diameter between 0.8 and 1.3 microm, respectively. Volumes of 5 l of distilled water were filtered tangentially for 3 h under an applied pressure of 3.5 and 5.5 bar. The retention of tubular supports prepared was tested with molecules of varying size (Evans blue, NaCl and Sacharose). The study of the liquid filtration and flow through these supports showed that the retention rate depends on support composition and pore diameter, and solute molecular weight. The S1 support (mixture of barbotine and 1% (w/w) activated carbon) gave a flux for distilled water of 68 L/m2 h while the double-layered support resulted in a flux of 8 L/m2 h for the same solution at the pressure of 3.5 bar. At a pressure of 5.5 bar an increase in the distilled water flux through the various supports was observed. It was significant for the S1 support (230 L/m h).

  11. [The effect of composition and structure of radiological equivalent materials on radiological equivalent].

    PubMed

    Wang, Y; Lin, D; Fu, T

    1997-03-01

    Morphology of inorganic material powders before and after being treated by ultrafine crush was observed by transformite electron microscope. The length and diameter of granules were measured. Polymers inorganic material powders before and after being treated by ultrafine crush were used for preparing radiological equivalent materials. Blending compatibility of inorganic meterials with polymer materials was observed by scanning electron microscope. CT values of tissue equivalent materials were measured by X-ray CT. Distribution of inorganic materials was examined. The compactness of materials was determined by the water absorbed method. The elastic module of materials was measured by laser speckle interferementry method. The results showed that the inorganic material powders treated by the ultrafine crush blent well with polymer and the distribution of these powders in the polymer was homogeneous. The equivalent errors of linear attenuation coefficients and CT values of equivalent materials were small. Their elastic modules increased one order of magnitude from 6.028 x 10(2) kg/cm2 to 9.753 x 10(3) kg/cm2. In addition, the rod inorganic material powders having rod granule blent easily with polymer. The present study provides a theoretical guidance and experimental basis for the design and synthesis of radiological equivalent materials.

  12. Multifunctional nanocrystals

    DOEpatents

    Klimov, Victor I.; Hollingsworth, Jennifer A.; Crooker, Scott A.; Kim, Hyungrak

    2010-06-22

    Multifunctional nanocomposites are provided including a core of either a magnetic material or an inorganic semiconductor, and, a shell of either a magnetic material or an inorganic semiconductor, wherein the core and the shell are of differing materials, such multifunctional nanocomposites having multifunctional properties including magnetic properties from the magnetic material and optical properties from the inorganic semiconductor material. Various applications of such multifunctional nanocomposites are also provided.

  13. Methods of capturing and immobilizing radioactive nuclei with metal fluorite-based inorganic materials

    DOEpatents

    Wang, Yifeng; Miller, Andy; Bryan, Charles R.; Kruichak, Jessica Nicole

    2015-11-17

    Methods of capturing and immobilizing radioactive nuclei with metal fluorite-based inorganic materials are described. For example, a method of capturing and immobilizing radioactive nuclei includes flowing a gas stream through an exhaust apparatus. The exhaust apparatus includes a metal fluorite-based inorganic material. The gas stream includes a radioactive species. The radioactive species is removed from the gas stream by adsorbing the radioactive species to the metal fluorite-based inorganic material of the exhaust apparatus.

  14. Preparation and characterization of PVDF-glass fiber composite membrane reinforced by interfacial UV-grafting copolymerization.

    PubMed

    Luo, Nan; Xu, Rongle; Yang, Min; Yuan, Xing; Zhong, Hui; Fan, Yaobo

    2015-12-01

    A novel inorganic-organic composite membrane, namely poly(vinylidene fluoride) PVDF-glass fiber (PGF) composite membrane, was prepared and reinforced by interfacial ultraviolet (UV)-grafting copolymerization to improve the interfacial bonding strength between the membrane layer and the glass fiber. The interfacial polymerization between inorganic-organic interfaces is a chemical cross-linking reaction that depends on the functionalized glass fiber with silane coupling (KH570) as the initiator and the polymer solution with acrylamide monomer (AM) as the grafting block. The Fourier transform infrared spectrometer-attenuated total reflectance (FTIR-ATR) spectra and the energy dispersive X-ray (EDX) pictures of the interface between the glass fiber and polymer matrix confirmed that the AM was grafted to the surface of the glass fiber fabric and that the grafting polymer was successfully embedded in the membrane matrix. The formation mechanisms, permeation, and anti-fouling performance of the PGF composite membrane were measured with different amounts of AM in the doping solutions. The results showed that the grafting composite membrane improved the interfacial bonding strength and permeability, and the peeling strength was improved by 32.6% for PGF composite membranes with an AM concentration at 2wt.%. Copyright © 2015. Published by Elsevier B.V.

  15. Synthesis of macroporous structures

    DOEpatents

    Stein, Andreas; Holland, Brian T.; Blanford, Christopher F.; Yan, Hongwei

    2004-01-20

    The present application discloses a method of forming an inorganic macroporous material. In some embodiments, the method includes: providing a sample of organic polymer particles having a particle size distribution of no greater than about 10%; forming a colloidal crystal template of the sample of organic polymer particles, the colloidal crystal template including a plurality of organic polymer particles and interstitial spaces therebetween; adding an inorganic precursor composition including a noncolloidal inorganic precursor to the colloidal crystal template such that the precursor composition permeates the interstitial spaces between the organic polymer particles; converting the noncolloidal inorganic precursor to a hardened inorganic framework; and removing the colloidal crystal template from the hardened inorganic framework to form a macroporous material. Inorganic macroporous materials are also disclosed.

  16. Organic-inorganic hybrid materials as semiconducting channels in thin-film field-effect transistors

    PubMed

    Kagan; Mitzi; Dimitrakopoulos

    1999-10-29

    Organic-inorganic hybrid materials promise both the superior carrier mobility of inorganic semiconductors and the processability of organic materials. A thin-film field-effect transistor having an organic-inorganic hybrid material as the semiconducting channel was demonstrated. Hybrids based on the perovskite structure crystallize from solution to form oriented molecular-scale composites of alternating organic and inorganic sheets. Spin-coated thin films of the semiconducting perovskite (C(6)H(5)C(2)H(4)NH(3))(2)SnI(4) form the conducting channel, with field-effect mobilities of 0.6 square centimeters per volt-second and current modulation greater than 10(4). Molecular engineering of the organic and inorganic components of the hybrids is expected to further improve device performance for low-cost thin-film transistors.

  17. Cross-Linking Reactions for the Conversion of Polyphosphazenes into Useful Materials

    DTIC Science & Technology

    1994-05-18

    Characteristics of Polymeric Materials Polymers form one of the largest classes of materials.I Together with ceramics, metals, and a number of inorganic ...the (mainly inorganic ) ceramics, semiconductors, metals, and electro-optical materials. As such, they provide access to combinations of properties that...are not found in any of the classical materials areas. Because the field of inorganic /organic materials is one of the most promising areas for the

  18. Hydrogen-permeable composite metal membrane and uses thereof

    DOEpatents

    Edlund, D.J.; Friesen, D.T.

    1993-06-08

    Various hydrogen production and hydrogen sulfide decomposition processes are disclosed that utilize composite metal membranes that contain an intermetallic diffusion barrier separating a hydrogen-permeable base metal and a hydrogen-permeable coating metal. The barrier is a thermally stable inorganic proton conductor.

  19. Fabrication and evaluation of novel zeolite membranes to control the neoplastic activity and anti-tumoral drug treatments in human breast cancer cells. Part 1: Synthesis and characterization of Pure Zeolite Membranes and Mixed Matrix Membranes for adhesion and growth of cancer cells.

    PubMed

    Tavolaro, Palmira; Martino, Guglielmo; Andò, Sebastiano; Tavolaro, Adalgisa

    2016-12-01

    Novel pure and hybrid zeolite membranes were prepared with appropriate different physicochemical characteristics such as frameworks, hydrophilicity, crystal size, chemical composition, acid-base properties (Point of Zero Charge, PZC) and surface morphology and used in inorganic cell/scaffold constructs. Because the control of cell interactions, as the adhesion, proliferation, remodelling and mobility, is important for differentiation and progression of tumors, this work focused on response of cancer cells adhered and grown on synthesized zeolite surfaces in order to study the influence of these scaffolds in controlled conditions. We have selected the MCF-7 and MDA-MB-231 human breast cancer cell line as model tumor cell lines. This study showed that all the zeolite membranes synthesized are excellent scaffolds because they are very selective materials to support the adhesion and growth of neoplastic cells. All zeolite scaffolds were characterized by FESEM, FTIR ATR, XRD, AFM, PZC and contact angle analyses. Cell adhesion, viability and morphology were measured by count, MTT assay and FESEM microphotography analysis, at various incubation times. Copyright © 2016. Published by Elsevier B.V.

  20. The Effect of Silane Addition on Chitosan-Fly Ash/CTAB as Electrolyte Membrane

    NASA Astrophysics Data System (ADS)

    Kusumastuti, E.; Isnaeni, D.; Sulistyaningsih, T.; Mahatmanti, F. W.; Jumaeri; Atmaja, L.; Widiastuti, N.

    2017-02-01

    Electrolyte membrane is an important component in fuel cell system, because it may influence fuel cell performance. Many efforts have been done to produce electrolyte membrane to replace comercial membrane. In this research, electrolyte membrane is composed of chitosan as an organic matrix and fly ash modified with CTAB and silane as inorganic filler. Fly ash is modified using silane as coupling agent to improve interfacial morphology between organic matrix and inorganic filler. This research aims to determine the best membrane performance based on its characteristics such as water uptake, mechanical properties, proton conductivity, and methanol permeability. The steps that have been done include silica preparation from fly ash, modification of silica surface with CTAB, silica coupling process with silane, synthesis of membranes with inversion phase method, and membrane characterization. The result shows that membrane C-FA/CTAB-Silane 10% (w/w) has the best performance with proton conductivity 8.00 x 10-4 S.cm-1, methanol permeability 3.37 x 10-7 cm.s-1, and selectivity 2.12 x 103 S.s.cm-3. The result of FTIR analysis on membrane C-FA/CTAB-Silane 10% shows that there is only physical interaction occured between chitosan, fly ash and silane, because there is no peak differences significantly at wave number 1000-1250 cm-1, while morphology analysis on membrane with Scanning Electron Microscopy (SEM) shows good dispersion and there is no agglomeration on chitosan matrix.

  1. Improved method for the determination of nonpurgeable suspended organic carbon in natural water by silver filter filtration, wet chemical oxidation, and infrared spectrometry

    USGS Publications Warehouse

    Burkhardt, Mark R.; Brenton, Ronald W.; Kammer, James A.; Jha, Virenda K.; O'Mara-Lopez, Peggy G.; Woodworth, Mark T.

    1999-01-01

    Precision and accuracy are reported for the first time for the analysis of nonpurgeable suspended organic carbon by silver membrane filtration followed by wet chemical oxidation. A water sample is pressure filtered through a 0.45‐μm‐pore‐size, 47‐mm‐diameter silver membrane filter. The silver membrane filter then is cut into ribbons and placed in a flame‐sealable glass ampule. The organic material trapped on the membrane filter strips is acidified, purged with oxygen to remove inorganic carbonates and volatile organic compounds, and oxidized to carbon dioxide (CO2) using phosphoric acid and potassium persulfate in the sealed glass ampule. The resulting CO2 is measured by a nondispersive infrared CO2 detector. The amount of CO2 is proportional to the concentration of chemically oxidizable nonpurgeable organic carbon in the environmental water sample. The quantitation and method detection limit for routine analysis is 0.2 mg/L. The average percent recovery in five representative matrices was 97 ± 11%. The errors associated with sampling and sample preparation of nonpurgeable suspended organic carbon are also described.

  2. NREL Opens Large Database of Inorganic Thin-Film Materials | News | NREL

    Science.gov Websites

    Inorganic Thin-Film Materials April 3, 2018 An extensive experimental database of inorganic thin-film Energy Laboratory (NREL) is now publicly available. The High Throughput Experimental Materials (HTEM Schroeder / NREL) "All existing experimental databases either contain many entries or have all this

  3. Recent Applications of 2D Inorganic Nanosheets for Emerging Energy Storage System.

    PubMed

    Oh, Seung Mi; Patil, Sharad B; Jin, Xiaoyan; Hwang, Seong-Ju

    2018-04-03

    Among many types of nanostructured inorganic materials, highly anisotropic 2D nanosheets provide unique advantages in designing and synthesizing efficient electrode and electrocatalyst materials for novel energy storage technologies. 2D inorganic nanosheets boast lots of unique characteristics such as high surface area, short ion diffusion path, tailorable compositions, and tunable electronic structures. These merits of 2D inorganic nanosheets render them promising candidate materials as electrodes for diverse secondary batteries and supercapacitors, and electrocatalysts. A wide spectrum of examples is presented for inorganic nanosheet-based electrodes and electrocatalysts. Future perspectives in research about 2D nanosheet-based functional materials are discussed to provide insight for the development of next-generation energy storage systems using 2D nanostructured materials. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Strongly coupled inorganic-nano-carbon hybrid materials for energy storage.

    PubMed

    Wang, Hailiang; Dai, Hongjie

    2013-04-07

    The global shift of energy production from fossil fuels to renewable energy sources requires more efficient and reliable electrochemical energy storage devices. In particular, the development of electric or hydrogen powered vehicles calls for much-higher-performance batteries, supercapacitors and fuel cells than are currently available. In this review, we present an approach to synthesize electrochemical energy storage materials to form strongly coupled hybrids (SC-hybrids) of inorganic nanomaterials and novel graphitic nano-carbon materials such as carbon nanotubes and graphene, through nucleation and growth of nanoparticles at the functional groups of oxidized graphitic nano-carbon. We show that the inorganic-nano-carbon hybrid materials represent a new approach to synthesize electrode materials with higher electrochemical performance than traditional counterparts made by simple physical mixtures of electrochemically active inorganic particles and conducting carbon materials. The inorganic-nano-carbon hybrid materials are novel due to possible chemical bonding between inorganic nanoparticles and oxidized carbon, affording enhanced charge transport and increased rate capability of electrochemical materials without sacrificing specific capacity. Nano-carbon with various degrees of oxidation provides a novel substrate for nanoparticle nucleation and growth. The interactions between inorganic precursors and oxidized-carbon substrates provide a degree of control over the morphology, size and structure of the resulting inorganic nanoparticles. This paper reviews the recent development of inorganic-nano-carbon hybrid materials for electrochemical energy storage and conversion, including the preparation and functionalization of graphene sheets and carbon nanotubes to impart oxygen containing groups and defects, and methods of synthesis of nanoparticles of various morphologies on oxidized graphene and carbon nanotubes. We then review the applications of the SC-hybrid materials for high performance lithium ion batteries, rechargeable Li-S and Li-O2 batteries, supercapacitors and ultrafast Ni-Fe batteries, and new electrocatalysts for oxygen reduction, oxygen evolution and hydrogen evolution reactions.

  5. Bifunctionalized organic-inorganic charged nanocomposite membrane for pervaporation dehydration of ethanol.

    PubMed

    Tripathi, Bijay P; Kumar, Mahendra; Saxena, Arunima; Shahi, Vinod K

    2010-06-01

    Chitosan was modified into N-p-carboxy benzyl chitosan (NCBC) by introducing an aromatic ring grafted with acidic -COOH group and highly stable and cross-linked nanostructured NCBC-silica composite membranes were prepared for pervaporation dehydration of water-ethanol mixture. These membranes were tailored to comprise three regions namely: hydrophobic region, highly charged region and selective region, in which weak acidic group (-COOH) was grafted at organic segment while strong acidic group (-SO(3)H) was grafted at inorganic segment to achieve high stability and less swelling in water-ethanol mixture. Cross-linking density and NCBC-silica content in membrane matrix has been systematically optimized to control the nanostructure of the developed polymer matrix for studying the effects of molecular structure on the swelling, and PV performance. Among prepared membranes, nanocomposite membrane with 3h cross-linking time and 90% (w/w) of NCBC-silica content (PCS-3-3) exhibited 1.66×10(-4)cm(3)(STP) cm/cm(2) s cmHg water permeability (P(W)), while 1.35×10(-7) cm(3)(STP) cm/cm(2) s cmHg ethanol permeability (P(EtOH)) of developed membrane and 1231 PV selectivity factor at 30 °C for separating water from 90% (w/w) ethanol mixture. Copyright © 2010 Elsevier Inc. All rights reserved.

  6. Self-assembled hierarchically structured organic-inorganic composite systems.

    PubMed

    Tritschler, Ulrich; Cölfen, Helmut

    2016-05-13

    Designing bio-inspired, multifunctional organic-inorganic composite materials is one of the most popular current research objectives. Due to the high complexity of biocomposite structures found in nacre and bone, for example, a one-pot scalable and versatile synthesis approach addressing structural key features of biominerals and affording bio-inspired, multifunctional organic-inorganic composites with advanced physical properties is highly challenging. This article reviews recent progress in synthesizing organic-inorganic composite materials via various self-assembly techniques and in this context highlights a recently developed bio-inspired synthesis concept for the fabrication of hierarchically structured, organic-inorganic composite materials. This one-step self-organization concept based on simultaneous liquid crystal formation of anisotropic inorganic nanoparticles and a functional liquid crystalline polymer turned out to be simple, fast, scalable and versatile, leading to various (multi-)functional composite materials, which exhibit hierarchical structuring over several length scales. Consequently, this synthesis approach is relevant for further progress and scientific breakthrough in the research field of bio-inspired and biomimetic materials.

  7. Decomposition Behavior of Curcumin during Solar Irradiation when Contact with Inorganic Particles

    NASA Astrophysics Data System (ADS)

    Nandiyanto, A. B. D.; Wiryani, A. S.; Rusli, A.; Purnamasari, A.; Abdullah, A. G.; Riza, L. S.

    2017-03-01

    Curcumin is one of materials which have been widely used in medicine, Asian cuisine, and traditional cosmetic. Therefore, understanding the stability of curcumin has been widely studied. The purpose of this study was to investigate the stability of curcumin solution against solar irradiation when making contact with inorganic material. As a model for the inorganic material, titanium dioxide (TiO2) was used. In the experimental method, the curcumin solution was irradiated using a solar irradiation. To confirm the stability of curcumin when contact with inorganic material, we added TiO2 micro particles with different concentrations. The results showed that the concentration of curcumin decreased during solar irradiation. The less concentration of curcumin affected the more decomposition rate obtained. The decomposition rate was increased greatly when TiO2 was added, in which the more TiO2 concentration added allowed the faster decomposition rate. Based on the result, we conclude that the curcumin is relatively stable as long as using higher concentration of curcumin and is no inorganic material existed. Then, the decomposition can be minimized by avoiding contact with inorganic material.

  8. Organic/inorganic nanocomposites, methods of making, and uses as a permeable reactive barrier

    DOEpatents

    Harrup, Mason K [Idaho Falls, ID; Stewart, Frederick F [Idaho Falls, ID

    2007-05-15

    Nanocomposite materials having a composition including an inorganic constituent, a preformed organic polymer constituent, and a metal ion sequestration constituent are disclosed. The nanocomposites are characterized by being single phase, substantially homogeneous materials wherein the preformed polymer constituent and the inorganic constituent form an interpenetrating network with each other. The inorganic constituent may be an inorganic oxide, such as silicon dioxide, formed by the in situ catalyzed condensation of an inorganic precursor in the presence of the solvated polymer and metal ion sequestration constituent. The polymer constituent may be any hydrophilic polymer capable of forming a type I nanocomposite such as, polyacrylonitrile (PAN), polyethyleneoxide (PEO), polyethylene glycol (PEG), polyvinyl acetate (PVAc), polyvinyl alcohol (PVA), and combinations thereof. Nanocomposite materials of the present invention may be used as permeable reactive barriers (PRBs) to remediate contaminated groundwater. Methods for making nanocomposite materials, PRB systems, and methods of treating groundwater are also disclosed.

  9. Biomineralization-inspired synthesis of functional organic/inorganic hybrid materials: organic molecular control of self-organization of hybrids.

    PubMed

    Arakaki, Atsushi; Shimizu, Katsuhiko; Oda, Mayumi; Sakamoto, Takeshi; Nishimura, Tatsuya; Kato, Takashi

    2015-01-28

    Organisms produce various organic/inorganic hybrid materials, which are called biominerals. They form through the self-organization of organic molecules and inorganic elements under ambient conditions. Biominerals often have highly organized and hierarchical structures from nanometer to macroscopic length scales, resulting in their remarkable physical and chemical properties that cannot be obtained by simple accumulation of their organic and inorganic constituents. These observations motivate us to create novel functional materials exhibiting properties superior to conventional materials--both synthetic and natural. Herein, we introduce recent progress in understanding biomineralization processes at the molecular level and the development of organic/inorganic hybrid materials by these processes. We specifically outline fundamental molecular studies on silica, iron oxide, and calcium carbonate biomineralization and describe material synthesis based on these mechanisms. These approaches allow us to design a variety of advanced hybrid materials with desired morphologies, sizes, compositions, and structures through environmentally friendly synthetic routes using functions of organic molecules.

  10. A metamorphic inorganic framework that can be switched between eight single-crystalline states

    NASA Astrophysics Data System (ADS)

    Zhan, Caihong; Cameron, Jamie M.; Gabb, David; Boyd, Thomas; Winter, Ross S.; Vilà-Nadal, Laia; Mitchell, Scott G.; Glatzel, Stefan; Breternitz, Joachim; Gregory, Duncan H.; Long, De-Liang; MacDonell, Andrew; Cronin, Leroy

    2017-02-01

    The design of highly flexible framework materials requires organic linkers, whereas inorganic materials are more robust but inflexible. Here, by using linkable inorganic rings made up of tungsten oxide (P8W48O184) building blocks, we synthesized an inorganic single crystal material that can undergo at least eight different crystal-to-crystal transformations, with gigantic crystal volume contraction and expansion changes ranging from -2,170 to +1,720 Å3 with no reduction in crystallinity. Not only does this material undergo the largest single crystal-to-single crystal volume transformation thus far reported (to the best of our knowledge), the system also shows conformational flexibility while maintaining robustness over several cycles in the reversible uptake and release of guest molecules switching the crystal between different metamorphic states. This material combines the robustness of inorganic materials with the flexibility of organic frameworks, thereby challenging the notion that flexible materials with robustness are mutually exclusive.

  11. Biocellulose-based flexible magnetic paper

    NASA Astrophysics Data System (ADS)

    Barud, H. S.; Tercjak, A.; Gutierrez, J.; Viali, W. R.; Nunes, E. S.; Ribeiro, S. J. L.; Jafellici, M.; Nalin, M.; Marques, R. F. C.

    2015-05-01

    Biocellulose or bacterial cellulose (BC) is a biocompatible (nano) material produced with a three-dimensional network structure composed of microfibrils having nanometric diameters obtained by the Gluconacetobacter xylinus bacteria. BC membranes present relatively high porosity, allowing the incorporation or synthesis in situ of inorganic nanoparticles for multifunctional applications and have been used as flexible membranes for incorporation of magnetic nanocomposite. In this work, highly stable superparamagnetic iron oxide nanoparticles (SPION), functionalized with polyethylene glycol (PEG), with an average diameter of 5 nm and a saturation magnetization of 41 emu/g at 300 K were prepared. PEG-Fe2O3 hybrid was dispersed by mixing a pristine BC membrane in a stable aqueous dispersion of PEG-SPION. The PEG chains at PEG-SPION's surface provide a good permeability and strong affinity between the BC chains and SPION through hydrogen-bonding interactions. PEG-SPION also allow the incorporation of higher content of nanoparticles without compromising the mechanical properties of the nanocomposite. Structural and magnetic properties of the composite have been characterized by XRD, SEM, energy-dispersive X-ray spectroscopy (EDX), magnetization, Raman spectroscopy, and magnetic force microscopy.

  12. [Pollution prevention and control of aqueous extract of astragali radix processed with ZrO2 inorganic ceramic membrane micro-filtration].

    PubMed

    Pan, Lin-Men; Huang, Min-Yan; Guo, Li-Wei

    2012-11-01

    To study the measures for preventing and controlling the pollution of aqueous extract of Astragali Radix proceeded with inorganic ceramic membrane micro-filtration, in order to find effective measures for preventing and controlling the membrane pollution. The resistance distribution, polymer removal and changes in physical and chemical parameters of the zirconium oxide film of different pore diameters were determined to analyze the state or location of pollutants as well as the regularity of formation. Meanwhile, recoil and ultrasonic physical measures were adopted to strengthen the membrane process, in order to explore the methods for preventing and controlling the membrane pollution. When 0.2 microm of ZrO2 micro-filtrated aqueous extract of Astragali Radix, the rate of pollution was as high as 44.9%. The hole blocking resistance and the concentration polarization resistance were the main filtration resistances, while the surface deposit resistance decreased with the increase in the membrane's hold diameter; after micro-filtration, the liquid turbidity significantly reduced, with slight changes in both pH and viscosity. The 0.2 microm ZrO2 micro-filtration membrane performed better than the 0.05 microm pore size membrane in terms of conductivity. The 0. 2 microm and 0.05 microm pore diameter membranes showed better performance in the removal of pectin. The ultrasonic measure to strengthen membranes is more suitable to this system, with a flux rate up by 41.7%. The membrane optimization process adopts appropriate measures for preventing and controlling the membrane pollution, in order to reduce the membrane pollution, recover membrane performance and increase filtration efficiency.

  13. A biochemical network can control formation of a synthetic material by sensing numerous specific stimuli

    NASA Astrophysics Data System (ADS)

    Hun Yeon, Ju; Chan, Karen Y. T.; Wong, Ting-Chia; Chan, Kelvin; Sutherland, Michael R.; Ismagilov, Rustem F.; Pryzdial, Edward L. G.; Kastrup, Christian J.

    2015-05-01

    Developing bio-compatible smart materials that assemble in response to environmental cues requires strategies that can discriminate multiple specific stimuli in a complex milieu. Synthetic materials have yet to achieve this level of sensitivity, which would emulate the highly evolved and tailored reaction networks of complex biological systems. Here we show that the output of a naturally occurring network can be replaced with a synthetic material. Exploiting the blood coagulation system as an exquisite biological sensor, the fibrin clot end-product was replaced with a synthetic material under the biological control of a precisely regulated cross-linking enzyme. The functions of the coagulation network remained intact when the material was incorporated. Clot-like polymerization was induced in indirect response to distinct small molecules, phospholipids, enzymes, cells, viruses, an inorganic solid, a polyphenol, a polysaccharide, and a membrane protein. This strategy demonstrates for the first time that an existing stimulus-responsive biological network can be used to control the formation of a synthetic material by diverse classes of physiological triggers.

  14. Pervaporation Separation of Water-Ethanol Mixtures Using Organic-Inorganic Nanocomposite Membranes

    EPA Science Inventory

    Preyssler type heteropolyacid viz., H14[NaP5W30O110] incorporated chitosan nanocomposite membranes (NCMs) were prepared by solution casting, characterized using a variety of techniques and employed in the pervaporation separation of water-ethanol mixtures as a function of feed wa...

  15. Ceramic membranes having macroscopic channels

    DOEpatents

    Anderson, Marc A.; Peterson, Reid A.

    1996-01-01

    Methods have been developed to make porous ceramic membranes having macroscopic channels therethrough. The novel membranes are formed by temporarily supporting the sol-gel membrane precursor on an organic support which is ultimately removed from the interior of the membrane, preferably by pyrolysis or by chemical destruction. The organic support may also include an inorganic metal portion that remains on destruction of the organic portion, providing structural support and/or chemical reactivity to the membrane. The channels formed when the organic support is destroyed provide the ability to withdraw small catalytic products or size-separated molecules from the metal oxide membrane. In addition, the channel-containing membranes retain all of the advantages of existing porous ceramic membranes.

  16. Ceramic membranes having macroscopic channels

    DOEpatents

    Anderson, M.A.; Peterson, R.A.

    1996-09-03

    Methods have been developed to make porous ceramic membranes having macroscopic channels therethrough. The novel membranes are formed by temporarily supporting the sol-gel membrane precursor on an organic support which is ultimately removed from the interior of the membrane, preferably by pyrolysis or by chemical destruction. The organic support may also include an inorganic metal portion that remains on destruction of the organic portion, providing structural support and/or chemical reactivity to the membrane. The channels formed when the organic support is destroyed provide the ability to withdraw small catalytic products or size-separated molecules from the metal oxide membrane. In addition, the channel-containing membranes retain all of the advantages of existing porous ceramic membranes. 1 fig.

  17. Membrane fouling of forward osmosis (FO) membrane for municipal wastewater treatment: A comparison between direct FO and OMBR.

    PubMed

    Sun, Yan; Tian, Jiayu; Zhao, Zhiwei; Shi, Wenxin; Liu, Dongmei; Cui, Fuyi

    2016-11-01

    In this work, membrane fouling behavior in a direct forward osmosis (FO) and an osmotic membrane bioreactor (OMBR) for municipal wastewater treatment was systematically investigated and compared. During the long-term operation, much severer flux decline was observed for the direct FO than that for the OMBR. The cake layer was found to be much thicker, together with large amounts of microorganisms growing on the membrane surface in direct FO. Interestingly, no obvious attachment of microorganisms on the membrane surface was observed in the OMBR. The fourier transform infrared spectroscopy (FTIR) and excitation emission matrices (EEM) analyses showed the polysaccharides and proteins were the dominant organic foulants in the fouling layer, and the quantity of the organic substances was also higher in direct FO than that in OMBR. Energy-dispersive X-ray (EDX) results indicated the main inorganic elements in the fouling layer were Ca, Mg, Fe and P, all of which exhibited higher relative percentages in direct FO than that in OMBR. The occurrence of higher contents of microorganisms, organic foulants and inorganic elements in the cake layer caused a higher filtration resistance for the FO membrane in the direct FO. Although more severe membrane fouling was identified in direct FO, the hydraulic and chemical cleaning was more effective on recovering the water permeability of the membrane in direct FO than that in OMBR. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Inorganic membranes for carbon capture and power generation

    NASA Astrophysics Data System (ADS)

    Snider, Matthew T.

    Inorganic membranes are under consideration for cost-effective reductions of carbon emissions from coal-fired power plants, both in the capture of pollutants post-firing and in the direct electrochemical conversion of coal-derived fuels for improved plant efficiency. The suitability of inorganic membrane materials for these purposes stems as much from thermal and chemical stability in coal plant operating conditions as from high performance in gas separations and power generation. Hydrophilic, micro-porous zeolite membrane structures are attractive for separating CO2 from N2 in gaseous waste streams due to the attraction of CO2 to the membrane surface and micropore walls that gives the advantage to CO2 transport. Recent studies have indicated that retention of the templating agent used in zeolite synthesis can further block N2 from the micropore interior and significantly improve CO2/N2 selectivity. However, the role of the templating agent in micro-porous transport has not been well investigated. In this work, gas sorption studies were conducted by high-pressure thermo-gravimetric analysis on Zeolite Y membrane materials to quantify the effect of the templating agent on CO2, N2, and H2O adsorption/desorption, as well as to examine the effect of humidification on overall membrane performance. In equilibrium conditions, the N2 sorption enthalpy was nearly unchanged by the presence of the templating agent, but the N2 pore occupation was reduced ˜1000x. Thus, the steric nature of the blocking of N2 from the micropores by the templating agent was confirmed. CO2 and H2O sorption enthalpies were similarly unaffected by the templating agent, and the micropore occupations were only reduced as much as the void volume taken up by the templating agent. Thus, the steric blocking effect did not occur for molecules more strongly attracted to the micropore walls. Additionally, in time-transient measurements the CO 2 and H2O mobilities were significantly enhanced by the presence of the templating agent. This meant that small restrictions in the micropores were beneficial to the transport of molecules with some attraction to the micropore walls. Further evidence of this effect were discovered in transport studies on Zeolite Y membranes, in which small amounts of residual water were observed to enhance the CO2 permeance in a similar way as the templating agent in the powder. However, the effect was only observed for dry CO 2 streams and previously humidified membranes. H2O affinity for the zeolite framework was so high and mobility in the micropores was so low that even 0.8 mol% H2O included in the gas stream was enough to reduce CO2 transport by 100x. This poses a serious concern for carbon capture by zeolite Y membrane in coal-fired power plants: the waste stream must be dehumidified first. In the long-term, raising the efficiencies of fossil-fuel power plants is preferable to post-combustion capture for cost- and resource-effective carbon emissions reduction. Supplementing combustion of the fuel with electrochemical conversion by solid oxide fuel cell (SOFC) shows promise in this effort. Thin-film (<1microm thick) SOFCs have recently exhibited power densities at low temperature (LT) that rival those of thick-film, high-temperature designs, with improved stability and quick ramp times. Low operating temperatures also provide the potential for fast, high-volume production, but so far high-performing LT-SOFCs have all been made by micro-fabrication methods. In this work, thin-film LT-SOFC modules were fabricated by colloidal processing and their performance was demonstrated. Nano-particulate colloid syntheses, dip-coating, and rapid thermal processing methods yielded fine-particle membrane microstructures, with high porosity and conductivity in the platinum/gadolinium-doped ceria (GDC) composite electrodes and density in the yttria-stabilized zirconia (YSZ) electrolytes. Power densities of >1000 W/m2 at 450°C and ˜5000 W/m2 at 600°C were achieved, and the modules ran >100hrs at peak power after 8 thermal cycles. Thus it was demonstrated that high performing LT-SOFCs can be produced with large-scale methods.

  19. Porous Inorganic Drug Delivery Systems-a Review.

    PubMed

    Sayed, E; Haj-Ahmad, R; Ruparelia, K; Arshad, M S; Chang, M-W; Ahmad, Z

    2017-07-01

    Innovative methods and materials have been developed to overcome limitations associated with current drug delivery systems. Significant developments have led to the use of a variety of materials (as excipients) such as inorganic and metallic structures, marking a transition from conventional polymers. Inorganic materials, especially those possessing significant porosity, are emerging as good candidates for the delivery of a range of drugs (antibiotics, anticancer and anti-inflammatories), providing several advantages in formulation and engineering (encapsulation of drug in amorphous form, controlled delivery and improved targeting). This review focuses on key selected developments in porous drug delivery systems. The review provides a short broad overview of porous polymeric materials for drug delivery before focusing on porous inorganic materials (e.g. Santa Barbara Amorphous (SBA) and Mobil Composition of Matter (MCM)) and their utilisation in drug dosage form development. Methods for their preparation and drug loading thereafter are detailed. Several examples of porous inorganic materials, drugs used and outcomes are discussed providing the reader with an understanding of advances in the field and realistic opportunities.

  20. Design and synthesis of polyoxometalate-framework materials from cluster precursors

    NASA Astrophysics Data System (ADS)

    Vilà-Nadal, Laia; Cronin, Leroy

    2017-10-01

    Inorganic oxide materials are used in semiconductor electronics, ion exchange, catalysis, coatings, gas sensors and as separation materials. Although their synthesis is well understood, the scope for new materials is reduced because of the stability limits imposed by high-temperature processing and top-down synthetic approaches. In this Review, we describe the derivatization of polyoxometalate (POM) clusters, which enables their assembly into a range of frameworks by use of organic or inorganic linkers. Additionally, bottom-up synthetic approaches can be used to make metal oxide framework materials, and the features of the molecular POM precursors are retained in these structures. Highly robust all-inorganic frameworks can be made using metal-ion linkers, which combine molecular synthetic control without the need for organic components. The resulting frameworks have high stability, and high catalytic, photochemical and electrochemical activity. Conceptually, these inorganic oxide materials bridge the gap between zeolites and metal-organic frameworks (MOFs) and establish a new class of all-inorganic POM frameworks that can be designed using topological and reactivity principles similar to MOFs.

  1. Water-equivalent fiber radiation dosimeter with two scintillating materials

    PubMed Central

    Qin, Zhuang; Hu, Yaosheng; Ma, Yu; Lin, Wei; Luo, Xianping; Zhao, Wenhui; Sun, Weimin; Zhang, Daxin; Chen, Ziyin; Wang, Boran; Lewis, Elfed

    2016-01-01

    An inorganic scintillating material plastic optical fiber (POF) dosimeter for measuring ionizing radiation during radiotherapy applications is reported. It is necessary that an ideal dosimeter exhibits many desirable qualities, including water equivalence, energy independence, reproducibility, dose linearity. There has been much recent research concerning inorganic dosimeters. However, little reference has been made to date of the depth-dose characteristics of dosimeter materials. In the case of inorganic scintillating materials, they are predominantly non water-equivalent, with their effective atomic weight (Zeff) being typically much greater than that of water. This has been a barrier in preventing inorganic scintillating material dosimeter from being used in actual clinical applications. In this paper, we propose a parallel-paired fiber light guide structure to solve this problem. Two different inorganic scintillating materials are embedded separately in the parallel-paired fiber. It is shown that the information of water depth and absorbed dose at the point of measurement can be extracted by utilizing their different depth-dose properties. PMID:28018715

  2. Casting fine grained, fully dense, strong inorganic materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brown, Sam W.; Spencer, Larry S.; Phillips, Michael R.

    2015-11-24

    Methods and apparatuses for casting inorganic materials are provided. The inorganic materials include metals, metal alloys, metal hydrides and other materials. Thermal control zones may be established to control the propagation of a freeze front through the casting. Agitation from a mechanical blade or ultrasonic energy may be used to reduce porosity and shrinkage in the casting. After solidification of the casting, the casting apparatus may be used to anneal the cast part.

  3. Fluidizable particulate materials and methods of making same

    DOEpatents

    Gupta, Raghubir P.

    1999-01-01

    The invention provides fluidizable, substantially spherical particulate material of improved attrition resistance having an average particle size from about 100 to about 400 microns useful as sorbents, catalysts, catalytic supports, specialty ceramics or the like. The particles are prepared by spray drying a slurry comprising inorganic starting materials and an organic binder. Exemplary inorganic starting materials include mixtures of zinc oxide with titanium dioxide, or with iron oxide, alumina or the like. Exemplary organic binders include polyvinyl alcohol, hydroxypropylemethyl cellulose, polyvinyl acetate and the like. The spray dried particles are heat treated at a first temperature wherein organic binder material is removed to thereby provide a porous structure to the particles, and thereafter the particles are calcined at a higher temperature to cause reaction of the inorganic starting materials and to thereby form the final inorganic particulate material.

  4. Microbial fuel cells

    DOEpatents

    Nealson, Kenneth H; Pirbazari, Massoud; Hsu, Lewis

    2013-04-09

    A microbial fuel cell includes an anode compartment with an anode and an anode biocatalyst and a cathode compartment with a cathode and a cathode biocatalyst, with a membrane positioned between the anode compartment and the cathode compartment, and an electrical pathway between the anode and the cathode. The anode biocatalyst is capable of catalyzing oxidation of an organic substance, and the cathode biocatalyst is capable of catalyzing reduction of an inorganic substance. The reduced organic substance can form a precipitate, thereby removing the inorganic substance from solution. In some cases, the anode biocatalyst is capable of catalyzing oxidation of an inorganic substance, and the cathode biocatalyst is capable of catalyzing reduction of an organic or inorganic substance.

  5. Colloidal interactions and fouling of NF and RO membranes: a review.

    PubMed

    Tang, Chuyang Y; Chong, T H; Fane, Anthony G

    2011-05-11

    Colloids are fine particles whose characteristic size falls within the rough size range of 1-1000 nm. In pressure-driven membrane systems, these fine particles have a strong tendency to foul the membranes, causing a significant loss in water permeability and often a deteriorated product water quality. There have been a large number of systematic studies on colloidal fouling of reverse osmosis (RO) and nanofiltration (NF) membranes in the last three decades, and the understanding of colloidal fouling has been significantly advanced. The current paper reviews the mechanisms and factors controlling colloidal fouling of both RO and NF membranes. Major colloidal foulants (including both rigid inorganic colloids and organic macromolecules) and their properties are summarized. The deposition of such colloidal particles on an RO or NF membrane forms a cake layer, which can adversely affect the membrane flux due to 1) the cake layer hydraulic resistance and/or 2) the cake-enhanced osmotic pressure. The effects of feedwater compositions, membrane properties, and hydrodynamic conditions are discussed in detail for inorganic colloids, natural organic matter, polysaccharides, and proteins. In general, these effects can be readily explained by considering the mass transfer near the membrane surface and the colloid-membrane (or colloid-colloid) interaction. The critical flux and limiting flux concepts, originally developed for colloidal fouling of porous membranes, are also applicable to RO and NF membranes. For small colloids (diameter≪100 nm), the limiting flux can result from two different mechanisms: 1) the diffusion-solubility (gel formation) controlled mechanism and 2) the surface interaction controlled mechanism. The former mechanism probably dominates for concentrated solutions, while the latter mechanism may be more important for dilute solutions. Future research needs on RO and NF colloidal fouling are also identified in the current paper. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. Increasing the operation temperature of polymer electrolyte membranes for fuel cells: From nanocomposites to hybrids

    NASA Astrophysics Data System (ADS)

    Licoccia, Silvia; Traversa, Enrico

    Among the possible systems investigated for energy production with low environmental impact, polymeric electrolyte membrane fuel cells (PEMFCs) are very promising as electrochemical power sources for application in portable technology and electric vehicles. For practical applications, operating FCs at temperatures above 100 °C is desired, both for hydrogen and methanol fuelled cells. When hydrogen is used as fuel, an increase of the cell temperature produces enhanced CO tolerance, faster reaction kinetics, easier water management and reduced heat exchanger requirement. The use of methanol instead of hydrogen as a fuel for vehicles has several practical benefits such as easy transport and storage, but the slow oxidation kinetics of methanol needs operating direct methanol fuel cells (DMFCs) at intermediate temperatures. For this reason, new membranes are required. Our strategy to achieve the goal of operating at temperatures above 120 °C is to develop organic/inorganic hybrid membranes. The first approach was the use of nanocomposite class I hybrids where nanocrystalline ceramic oxides were added to Nafion. Nanocomposite membranes showed enhanced characteristics, hence allowing their operation up to 130 °C when the cell was fuelled with hydrogen and up to 145 °C in DMFCs, reaching power densities of 350 mW cm -2. The second approach was to prepare Class II hybrids via the formation of covalent bonds between totally aromatic polymers and inorganic clusters. The properties of such covalent hybrids can be modulated by modifying the ratio between organic and inorganic groups and the nature of the chemical components allowing to reach high and stable conductivity values up to 6.4 × 10 -2 S cm -1 at 120 °C.

  7. Development of high power VRLA batteries using novel materials and processes

    NASA Astrophysics Data System (ADS)

    Soria, M. L.; Valenciano, J.; Ojeda, A.; Raybaut, G.; Ihmels, K.; Deiters, J.; Clement, N.; Morales, J.; Sánchez, L.

    Nowadays UPS manufacturers demand batteries with very high specific power and relatively low specific energy, because most mains failures can be defined as "microfailures", usually of the order of seconds. Due to this fact, it is not necessary to provide energy but power. Within a 3-year EU funded project, a new AGM valve-regulated lead-acid battery with weight and volume substantially reduced, as well as a substantial improvement in its reliability, is under development. These aspects can provide the achievement of a more efficient, safe and economic energy supply. Battery specific power is practically related to electrode area, so that its increase, and therefore an electrode thickness reduction, appear essential to achieve the project objectives. Furthermore, it is necessary to achieve a similar reduction in the conventional glass microfibre separator. But such thin material should have improved mechanical properties and can make the battery more prone to develop short circuits across the separator. In order to avoid this problem, a new microporous polyethylene membrane has been developed and tested, with excellent mechanical properties, high porosity and low pore size. For these reasons, the final separator configuration includes a combination of both materials, improved non-woven glass microfibre and the polyethylene membrane. Batteries are designed and assembled by Tudor (Exide Technologies) as battery manufacturer and will be tested in real conditions by MGE UPS Systems as end user. Daramic for the membrane and Bernard Dumas for the glass microfibre mat, have developed and supplied the separators, while the Inorganic Chemistry Department of Córdoba University carries out fundamental research studies on very thin electrodes.

  8. Sulphate absorption across biological membranes.

    PubMed

    Mitchell, Stephen C; Waring, Rosemary H

    2016-01-01

    1. Sulphonation is unusual amongst the common Phase II (condensation; synthetic) reactions experienced by xenobiotics, in that the availability of the conjugating agent, sulphate, may become a rate-limiting factor. This sulphate is derived within the body via the oxygenation of sulphur moieties liberated from numerous ingested compounds including the sulphur-containing amino acids. Preformed inorganic sulphate also makes a considerable contribution to this pool. 2. There has been a divergence of opinion as to whether or not inorganic sulphate may be readily absorbed from the gastrointestinal tract and this controversy still continues in some quarters. Even more so, is the vexing question of potential absorption of inorganic sulphate via the lungs and through the skin. 3. This review examines the relevant diverse literature and concludes that sulphate ions may move across biological membranes by means of specific transporters and, although the gastrointestinal tract is by far the major portal of entry, some absorption across the lungs and the skin may take place under appropriate circumstances.

  9. Methods for the additive manufacturing of semiconductor and crystal materials

    DOEpatents

    Stowe, Ashley C.; Speight, Douglas

    2016-11-22

    A method for the additive manufacturing of inorganic crystalline materials, including: physically combining a plurality of starting materials that are used to form an inorganic crystalline compound to be used as one or more of a semiconductor, scintillator, laser crystal, and optical filter; heating or melting successive regions of the combined starting materials using a directed heat source having a predetermined energy characteristic, thereby facilitating the reaction of the combined starting materials; and allowing each region of the combined starting materials to cool in a controlled manner, such that the desired inorganic crystalline compound results. The method also includes, prior to heating or melting the successive regions of the combined starting materials using the directed heat source, heating the combined starting materials to facilitate initial reaction of the combined starting materials. The method further includes translating the combined starting materials and/or the directed heat source between successive locations. The method still further includes controlling the mechanical, electrical, photonic, and/or optical properties of the inorganic crystalline compound.

  10. Bottom-up design of de novo thermoelectric hybrid materials using chalcogenide resurfacing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sahu, Ayaskanta; Russ, Boris; Su, Norman C.

    Hybrid organic/inorganic thermoelectric materials based on conducting polymers and inorganic nanostructures have been demonstrated to combine both the inherently low thermal conductivity of the polymer and the superior charge transport properties (high power factors) of the inorganic component. While their performance today still lags behind that of conventional inorganic thermoelectric materials, solution-processable hybrids have made rapid progress and also offer unique advantages not available to conventional rigid inorganic thermoelectrics, namely: (1) low cost fabrication on rigid and flexible substrates, as well as (2) engineering complex conformal geometries for energy harvesting/cooling. While the number of reports of new classes of viablemore » hybrid thermoelectric materials is growing, no group has reported a general approach for bottom-up design of both p- and n-type materials from one common base. Thus, unfortunately, the literature comprises mostly of disconnected discoveries, which limits development and calls for a first-principles approach for property manipulation analogous to doping in traditional semiconductor thermoelectrics. Here, molecular engineering at the organic/inorganic interface and simple processing techniques are combined to demonstrate a modular approach enabling de novo design of complex hybrid thermoelectric systems. Here, we chemically modify the surfaces of inorganic nanostructures and graft conductive polymers to yield robust solution processable p- and n-type inorganic/organic hybrid nanostructures. Our new modular approach not only offers researchers new tools to perform true bottom-up design of thermoelectric hybrids, but also strong performance advantages as well due to the quality of the designed interfaces. For example, we obtain enhanced power factors in existing (by up to 500% in Te/PEDOT:PSS) and novel (Bi 2S 3/PEDOT:PSS) p-type systems, and also generate water-processable and air-stable high performing n-type hybrid systems (Bi 2Te 3/PEDOT:PSS), thus highlighting the potency of our ex situ strategy in opening up new material options for thermoelectric applications. Finally, this strategy establishes a unique platform with broad handles for custom tailoring of thermal and electrical properties through hybrid material tunability and enables independent control over inorganic material chemistry, nanostructure geometry, and organic material properties, thus providing a robust pathway to major performance enhancements.« less

  11. Bottom-up design of de novo thermoelectric hybrid materials using chalcogenide resurfacing

    DOE PAGES

    Sahu, Ayaskanta; Russ, Boris; Su, Norman C.; ...

    2017-01-01

    Hybrid organic/inorganic thermoelectric materials based on conducting polymers and inorganic nanostructures have been demonstrated to combine both the inherently low thermal conductivity of the polymer and the superior charge transport properties (high power factors) of the inorganic component. While their performance today still lags behind that of conventional inorganic thermoelectric materials, solution-processable hybrids have made rapid progress and also offer unique advantages not available to conventional rigid inorganic thermoelectrics, namely: (1) low cost fabrication on rigid and flexible substrates, as well as (2) engineering complex conformal geometries for energy harvesting/cooling. While the number of reports of new classes of viablemore » hybrid thermoelectric materials is growing, no group has reported a general approach for bottom-up design of both p- and n-type materials from one common base. Thus, unfortunately, the literature comprises mostly of disconnected discoveries, which limits development and calls for a first-principles approach for property manipulation analogous to doping in traditional semiconductor thermoelectrics. Here, molecular engineering at the organic/inorganic interface and simple processing techniques are combined to demonstrate a modular approach enabling de novo design of complex hybrid thermoelectric systems. Here, we chemically modify the surfaces of inorganic nanostructures and graft conductive polymers to yield robust solution processable p- and n-type inorganic/organic hybrid nanostructures. Our new modular approach not only offers researchers new tools to perform true bottom-up design of thermoelectric hybrids, but also strong performance advantages as well due to the quality of the designed interfaces. For example, we obtain enhanced power factors in existing (by up to 500% in Te/PEDOT:PSS) and novel (Bi 2S 3/PEDOT:PSS) p-type systems, and also generate water-processable and air-stable high performing n-type hybrid systems (Bi 2Te 3/PEDOT:PSS), thus highlighting the potency of our ex situ strategy in opening up new material options for thermoelectric applications. Finally, this strategy establishes a unique platform with broad handles for custom tailoring of thermal and electrical properties through hybrid material tunability and enables independent control over inorganic material chemistry, nanostructure geometry, and organic material properties, thus providing a robust pathway to major performance enhancements.« less

  12. Nanostructured catalyst supports

    DOEpatents

    Zhu, Yimin; Goldman, Jay L.; Qian, Baixin; Stefan, Ionel C.

    2012-10-02

    The present invention relates to SiC nanostructures, including SiC nanopowder, SiC nanowires, and composites of SiC nanopowder and nanowires, which can be used as catalyst supports in membrane electrode assemblies and in fuel cells. The present invention also relates to composite catalyst supports comprising nanopowder and one or more inorganic nanowires for a membrane electrode assembly.

  13. Electrospun Superhydrophobic Organic/Inorganic Composite Nanofibrous Membranes for Membrane Distillation.

    PubMed

    Li, Xiong; Yu, Xufeng; Cheng, Cheng; Deng, Li; Wang, Min; Wang, Xuefen

    2015-10-07

    Electrospun superhydrophobic organic/inorganic composite nanofibrous membranes exhibiting excellent direct contact membrane distillation (DCMD) performance were fabricated by a facile route combining the hydrophobization of silica nanoparticles (SiO2 NPs) and colloid electrospinning of the hydrophobic silica/poly(vinylidene fluoride) (PVDF) matrix. Benefiting from the utilization of SiO2 NPs with three different particle sizes, the electrospun nanofibrous membranes (ENMs) were endowed with three different delicate nanofiber morphologies and fiber diameter distribution, high porosity, and superhydrophobic property, which resulted in excellent waterproofing and breathability. Significantly, structural attributes analyses have indicated the major contributing role of fiber diameter distribution on determining the augment of permeate vapor flux through regulating mean flow pore size (MFP). Meanwhile, the extremely high liquid entry pressure of water (LEPw, 2.40 ± 0.10 bar), robust nanofiber morphology of PVDF immobilized SiO2 NPs, remarkable mechanical properties, thermal stability, and corrosion resistance endowed the as-prepared membranes with prominent desalination capability and stability for long-term MD process. The resultant choreographed PVDF/silica ENMs with optimized MFP presented an outstanding permeate vapor flux of 41.1 kg/(m(2)·h) and stable low permeate conductivity (∼2.45 μs/cm) (3.5 wt % NaCl salt feed; ΔT = 40 °C) over a DCMD test period of 24 h without membrane pores wetting detected. This result was better than those of typical commercial PVDF membranes and PVDF and modified PVDF ENMs reported so far, suggesting them as promising alternatives for MD applications.

  14. Insight into the effect of organic and inorganic draw solutes on the flux stability and sludge characteristics in the osmotic membrane bioreactor.

    PubMed

    Siddique, Muhammad Saboor; Khan, Sher Jamal; Shahzad, Muhammad Aamir; Nawaz, Muhammad Saqib; Hankins, Nicholas P

    2018-02-01

    In this study, chloride based (CaCl 2 and MgCl 2 ) and acetate based (NaOAc and MgOAc) salts in comparison with NaCl were investigated as draw solutions (DS) to evaluate their viability in the osmotic membrane bioreactor (OMBR). Membrane distillation was coupled with an OMBR setup to develop a hybrid OMBR-MD system, for the production of clean water and DS recovery. Results demonstrate that organic DS were able to mitigate the salinity buildup in the bioreactor as compared to inorganic salts. Prolonged filtration runs were observed with MgCl 2 and MgOAc in contrast with other draw solutes at the same molar concentration. Significant membrane fouling was observed with NaOAc while rapid flux decline due to increased salinity build-up was witnessed with NaCl and CaCl 2 . Improved characteristics of mixed liquor in terms of sludge filterability, particle size, and biomass growth along with the degradation of soluble microbial products (SMP) were found with organic DS. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Studies on a novel approach for the separation of L-phenylalanine amino acid from fermentation broth using a newly developed charged ultrafiltration membrane. I. Single solute system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Agarwal, A.K.; Huang, R.Y.M.

    A newly developed thin-film composite (TFC) ultrafiltration membrane made of sulfonated poly(phenylene oxide) (SPPO) was used to establish the feasibility of separating L-phenylalanine from the fermentation broth containing a number of dissolved inorganic and organic solutes as an alternative approach to the currently used complex and uneconomical conventional ion-exchange schemes. It was found that the rejection of inorganic salts in a single component system was highly dependent on the feed solution concentration and varied inversely with it. The pH of the feed solution was found to have a strong effect on the rejection of L-phenylalanine, changing it from - 10more » to 90%. This rejection behavior was identical for the two TFC-SPPO membrane samples which had molecular weight cutoff ratings of 10,000 and 20,000, respectively, although the permeate flux of the latter sample was almost twice that of the former sample. It was found that glucose molecules were not rejected by the membrane. 11 refs., 18 figs., 2 tab.« less

  16. When 2D Materials Meet Molecules: Opportunities and Challenges of Hybrid Organic/Inorganic van der Waals Heterostructures.

    PubMed

    Gobbi, Marco; Orgiu, Emanuele; Samorì, Paolo

    2018-05-01

    van der Waals heterostructures, composed of vertically stacked inorganic 2D materials, represent an ideal platform to demonstrate novel device architectures and to fabricate on-demand materials. The incorporation of organic molecules within these systems holds an immense potential, since, while nature offers a finite number of 2D materials, an almost unlimited variety of molecules can be designed and synthesized with predictable functionalities. The possibilities offered by systems in which continuous molecular layers are interfaced with inorganic 2D materials to form hybrid organic/inorganic van der Waals heterostructures are emphasized. Similar to their inorganic counterpart, the hybrid structures have been exploited to put forward novel device architectures, such as antiambipolar transistors and barristors. Moreover, specific molecular groups can be employed to modify intrinsic properties and confer new capabilities to 2D materials. In particular, it is highlighted how molecular self-assembly at the surface of 2D materials can be mastered to achieve precise control over position and density of (molecular) functional groups, paving the way for a new class of hybrid functional materials whose final properties can be selected by careful molecular design. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Inorganic separator technology program

    NASA Technical Reports Server (NTRS)

    Smatko, J. S.; Weaver, R. D.; Kalhammer, F. R.

    1973-01-01

    Testing and failure analyses of silver zinc cells with largely inorganic separators were performed. The results showed that the wet stand and cycle life objective of the silver-zinc cell development program were essentially accomplished and led to recommendations for cell composition, design, and operation that should yield further improvement in wet and cycle life. A series of advanced inorganic materials was successfully developed and formulated into rigid and semiflexible separator samples. Suitable screening tests for evaluation of largely inorganic separators were selected and modified for application to the separator materials. The results showed that many of these formulations are potentially superior to previously used materials and permitted selection of three promising materials for further evaluation in silver-zinc cells.

  18. Advances in organic-inorganic hybrid sorbents for the extraction of organic and inorganic pollutants in different types of food and environmental samples.

    PubMed

    Ng, Nyuk-Ting; Kamaruddin, Amirah Farhan; Wan Ibrahim, Wan Aini; Sanagi, Mohd Marsin; Abdul Keyon, Aemi S

    2018-01-01

    The efficiency of the extraction and removal of pollutants from food and the environment has been an important issue in analytical science. By incorporating inorganic species into an organic matrix, a new material known as an organic-inorganic hybrid material is formed. As it possesses high selectivity, permeability, and mechanical and chemical stabilities, organic-inorganic hybrid materials constitute an emerging research field and have become popular to serve as sorbents in various separaton science methods. Here, we review recent significant advances in analytical solid-phase extraction employing organic-inorganic composite/nanocomposite sorbents for the extraction of organic and inorganic pollutants from various types of food and environmental matrices. The physicochemical characteristics, extraction properties, and analytical performances of sorbents are discussed; including morphology and surface characteristics, types of functional groups, interaction mechanism, selectivity and sensitivity, accuracy, and regeneration abilities. Organic-inorganic hybrid sorbents combined with extraction techniques are highly promising for sample preparation of various food and environmental matrixes with analytes at trace levels. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Inorganic-organic electrolyte materials for energy applications

    NASA Astrophysics Data System (ADS)

    Fei, Shih-To

    This thesis research is devoted to the development of phosphazene-based electrolyte materials for use in various energy applications. Phosphazenes are inorganic-organic materials that provide unusal synthetic advantages and unique process features that make them useful in energy research. This particular thesis consists of six chapters and is focused on four specific aspects: lithium battery, solar cell, and fuel cell electrolytes, and artificial muscles. Chapter 1 is written as an introduction and review of phosphazene electrolytes used in energy applications. In this introduction the basic history and characteristics of the phosphazenes are discussed briefly, followed by examples of current and future applications of phosphazene electrolytes related to energy. Notes are included on how the rest of the chapters relate to previous work. Chapters 2 and 3 discuss the conductivity and fire safety of ethyleneoxy phosphazene gel electrolytes. The current highly flammable configurations for rechargeable lithium batteries generate serious safety concerns. Although commercial fire retardant additives have been investigated, they tend to decrease the overall efficiency of the battery. In these two chapters the discussion is focused on ionically conductive, non-halogenated lithium battery additives based on a methoxyethoxyethoxyphosphazene oligomer and the corresponding high polymer, both of which can increase the fire resistance of a battery while retaining a high energy efficiency. Conductivities in the range of 10 -4 Scm-1 have been obtained for self-extinguishing, ion-conductive methoxyethoxyethoxyphosphazene oligomers. The addition of 25 wt% high polymeric poly[bis(methoxyethoxyethoxy)phosphazene] to propylene carbonate electrolytes lowers the flammability by 90% while maintaining a good ionic conductivity of 2.5x10--3 Scm -1 Chapter 2 is focused more on the electrochemical properties of the electrolytes and how they compare to other similar materials, while Chapter 3 emphasizes the flammability studies. Chapter 4 expands the application of the ethyleneoxy phosphazene system to dye sensitized solar cell systems, and uses this material as a model for the study of electrode-electrolyte interfaces. We report here the results of our study on polymer electrolyte infiltration and its effect on dye-sensitized solar cells. In-depth studies have been made to compare the effects of different cell assembly procedures on the electrochemical properties as well as infiltration of electrolytes into various electrode designs. The first part of the study is based on the use of thermoplastic phosphazene electrolytes and how the overall fabrication procedure affects electrochemical performance, and the second is the use of cross-section microscopy to characterize the degree of electrolyte infiltration into various nanostructured titanium dioxide electrode surfaces. The results of this study should eventually improve the efficiency and longevity of thermally stable polymer dye solar cell systems. In Chapter 5 the effect of pendant polymer design on methanol fuel cell membrane performance was investigated. A synthetic method is described to produce a proton conductive polymer membrane with a polynorbornane backbone and inorganic-organic cyclic phosphazene pendent groups that bear sulfonic acid units. This hybrid polymer combines the inherent hydrophobicity and flexibility of the organic polymer with the tuning advantages of the cyclic phosphazene to produce a membrane with high proton conductivity and low methanol crossover at room temperature. The ion exchange capacity (IEC), the water swelling behavior of the polymer, and the effect of gamma radiation crosslinking were studied, together with the proton conductivity and methanol permeability of these materials. A typical membrane had an IEC of 0.329 mmolg-1 and had water swelling of 50 wt%. The maximum proton conductivity of 1.13x10 -4 Scm-1 at room temperature is less than values reported for some commercially available materials such as Nafion. However the average methanol permeability was around 10-9 cms-1, which is one hundred times smaller than the value for Nafion. Thus, the new polymers are candidates for low-temperature direct methanol fuel cell membranes. Finally, Chapter 6 focuses on the electroactivity of a mixed-substituent phosphazene electrolyte and its viability as an actuator material. We report here an electrochemically responsive polymer hydrogel based on ionic crosslinking. The crosslinking by metal cations and anionic carboxylic acid side groups can be controlled by redox reactions. The crosslinks dissociate when the cation crosslinker is reduced to a lower oxidation state and reform following oxidation, which leads to a reversible and localized swelling--contraction. By choosing biocompatible components and miniaturization designs, the system has potential in microrobotic and biomedical applications.

  20. Inorganic composites for space applications

    NASA Technical Reports Server (NTRS)

    Malmendier, J. W.

    1984-01-01

    The development of inorganic composite materials for space applications is reviewed. The composites do not contain any organic materials, and therefore, are not subject to degradation by ultraviolet radiation, volatilization of constituents, or embrittlement at low temperatures. The composites consist of glass, glass/ceramics or ceramic matrices, reinforced by refractory whiskers or fibers. Such composites have the low thermal expansion, refractories, chemical stability and other desirable properties usually associated with the matrix materials. The composites also have a degree of toughness which is extraordinary for refractory inorganic materials.

  1. Charting the complete elastic properties of inorganic crystalline compounds

    PubMed Central

    de Jong, Maarten; Chen, Wei; Angsten, Thomas; Jain, Anubhav; Notestine, Randy; Gamst, Anthony; Sluiter, Marcel; Krishna Ande, Chaitanya; van der Zwaag, Sybrand; Plata, Jose J; Toher, Cormac; Curtarolo, Stefano; Ceder, Gerbrand; Persson, Kristin A.; Asta, Mark

    2015-01-01

    The elastic constant tensor of an inorganic compound provides a complete description of the response of the material to external stresses in the elastic limit. It thus provides fundamental insight into the nature of the bonding in the material, and it is known to correlate with many mechanical properties. Despite the importance of the elastic constant tensor, it has been measured for a very small fraction of all known inorganic compounds, a situation that limits the ability of materials scientists to develop new materials with targeted mechanical responses. To address this deficiency, we present here the largest database of calculated elastic properties for inorganic compounds to date. The database currently contains full elastic information for 1,181 inorganic compounds, and this number is growing steadily. The methods used to develop the database are described, as are results of tests that establish the accuracy of the data. In addition, we document the database format and describe the different ways it can be accessed and analyzed in efforts related to materials discovery and design. PMID:25984348

  2. Ionic Liquids and Poly(ionic liquid)s for Morphosynthesis of Inorganic Materials.

    PubMed

    Gao, Min-Rui; Yuan, Jiayin; Antonietti, Markus

    2017-04-24

    Ionic liquids (ILs) are new, innovative ionic solvents with rich physicochemical properties and intriguing pre-organized solvent structures; these materials offer great potential to impact across versatile areas of scientific research, for example, synthetic inorganic chemistry. Recent use of ILs as precursors, templates, and solvents has led to inorganic materials with tailored sizes, dimensionalities, morphologies, and functionalities that are difficult to obtain, or even not accessible, by using conventional solvents. Poly(ionic liquid)s (PILs) polymerized from IL monomers also raise the prospect of modifying nucleation, growth, and crystallization of inorganic objects, shedding light on the synthesis of a wide range of new materials. Here we survey recent key progress in using ILs and PILs in the field of synthetic inorganic chemistry. As well as highlighting the unique features of ILs and PILs that enable advanced synthesis, the effects of adding other solvents to the final products, along with the emerging applications of the created inorganic materials will be discussed. We finally provide an outlook on several development opportunities that could lead to new advancements of this exciting research field. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Biexciton Auger Recombination Differs in Hybrid and Inorganic Halide Perovskite Quantum Dots.

    PubMed

    Eperon, Giles E; Jedlicka, Erin; Ginger, David S

    2018-01-04

    We use time-resolved photoluminescence measurements to determine the biexciton Auger recombination rate in both hybrid organic-inorganic and fully inorganic halide perovskite nanocrystals as a function of nanocrystal volume. We find that the volume scaling of the biexciton Auger rate in the hybrid perovskites, containing a polar organic A-site cation, is significantly shallower than in the fully inorganic Cs-based nanocrystals. As the nanocrystals become smaller, the Auger rate in the hybrid nanocrystals increases even less than expected, compared to the fully inorganic nanocrystals, which already show a shallower volume dependence than other material systems such as chalcogenide quantum dots. This finding suggests there may be differences in the strength of Coulombic interactions between the fully inorganic and hybrid perovskites, which may prove to be crucial in selecting materials to obtain the highest performing devices in the future, and hints that there could be something "special" about the hybrid materials.

  4. Microbial Relevant Fouling in Membrane Bioreactors: Influencing Factors, Characterization, and Fouling Control

    PubMed Central

    Wu, Bing; Fane, Anthony G.

    2012-01-01

    Microorganisms in membrane bioreactors (MBRs) play important roles on degradation of organic/inorganic substances in wastewaters, while microbial deposition/growth and microbial product accumulation on membranes potentially induce membrane fouling. Generally, there is a need to characterize membrane foulants and to determine their relations to the evolution of membrane fouling in order to identify a suitable fouling control approach in MBRs. This review summarized the factors in MBRs that influence microbial behaviors (community compositions, physical properties, and microbial products). The state-of-the-art techniques to characterize biofoulants in MBRs were reported. The strategies for controlling microbial relevant fouling were discussed and the future studies on membrane fouling mechanisms in MBRs were proposed. PMID:24958297

  5. Properties of PMR Polyimides Improved by Preparation of Polyhedral Oligomeric Silsesquioxane (POSS) Nanocomposites

    NASA Technical Reports Server (NTRS)

    Campbell, Sandi G.; Lee, Andre

    2005-01-01

    The field of hybrid organic-inorganic materials has grown drastically over the last several years. This interest stems from our ever-increasing ability to custom-build and control molecular structure at several length scales. This ability to control both the composition and structure of hybrid materials is sometimes broadly referred to as nanocomposite systems. One class of hybrid (organic-inorganic) nanostructured material is polyhedral oligomeric silsesquioxane (POSS), shown in the preceding diagram. The hybrid composition gives POSS materials dramatically enhanced properties relative to traditional hydrocarbons and inorganics. An important benefit of this technology is that it makes possible the formulations of nanostructured chemicals with excellent thermal and oxidative stability. This is largely due to the inorganic component.

  6. Nanocomposites of polymer and inorganic nanoparticles for optical and magnetic applications

    PubMed Central

    Li, Shanghua; Meng Lin, Meng; Toprak, Muhammet S.; Kim, Do Kyung; Muhammed, Mamoun

    2010-01-01

    This article provides an up-to-date review on nanocomposites composed of inorganic nanoparticles and the polymer matrix for optical and magnetic applications. Optical or magnetic characteristics can change upon the decrease of particle sizes to very small dimensions, which are, in general, of major interest in the area of nanocomposite materials. The use of inorganic nanoparticles into the polymer matrix can provide high-performance novel materials that find applications in many industrial fields. With this respect, frequently considered features are optical properties such as light absorption (UV and color), and the extent of light scattering or, in the case of metal particles, photoluminescence, dichroism, and so on, and magnetic properties such as superparamagnetism, electromagnetic wave absorption, and electromagnetic interference shielding. A general introduction, definition, and historical development of polymer–inorganic nanocomposites as well as a comprehensive review of synthetic techniques for polymer–inorganic nanocomposites will be given. Future possibilities for the development of nanocomposites for optical and magnetic applications are also introduced. It is expected that the use of new functional inorganic nano-fillers will lead to new polymer–inorganic nanocomposites with unique combinations of material properties. By careful selection of synthetic techniques and understanding/exploiting the unique physics of the polymeric nanocomposites in such materials, novel functional polymer–inorganic nanocomposites can be designed and fabricated for new interesting applications such as optoelectronic and magneto-optic applications. PMID:22110855

  7. Biodiscovery of aluminum binding peptides

    NASA Astrophysics Data System (ADS)

    Adams, Bryn L.; Sarkes, Deborah A.; Finch, Amethist S.; Hurley, Margaret M.; Stratis-Cullum, Dimitra

    2013-05-01

    Cell surface peptide display systems are large and diverse libraries of peptides (7-15 amino acids) which are presented by a display scaffold hosted by a phage (virus), bacteria, or yeast cell. This allows the selfsustaining peptide libraries to be rapidly screened for high affinity binders to a given target of interest, and those binders quickly identified. Peptide display systems have traditionally been utilized in conjunction with organic-based targets, such as protein toxins or carbon nanotubes. However, this technology has been expanded for use with inorganic targets, such as metals, for biofabrication, hybrid material assembly and corrosion prevention. While most current peptide display systems employ viruses to host the display scaffold, we have recently shown that a bacterial host, Escherichia coli, displaying peptides in the ubiquitous, membrane protein scaffold eCPX can also provide specific peptide binders to an organic target. We have, for the first time, extended the use of this bacterial peptide display system for the biodiscovery of aluminum binding 15mer peptides. We will present the process of biopanning with macroscopic inorganic targets, binder enrichment, and binder isolation and discovery.

  8. A Review on Recent Patents and Applications of Inorganic Material Binding Peptides.

    PubMed

    Thota, Veeranjaneyulu; Perry, Carole C

    2017-01-01

    Although the popularity of using combinatorial display techniques for recognising unique peptides having high affinity for inorganic (nano) particles has grown rapidly, there are no systematic reviews showcasing current developments or patents on binding peptides specific to these materials. In this review, we summarize and discuss recent progress in patents on material binding peptides specifically exploring inorganic nano surfaces such as metals, metal oxides, minerals, carbonbased materials, polymer based materials, magnetic materials and semiconductors. We consider both the peptide display strategies used and the exploitation of the identified peptides in the generation of advanced nanomaterials. In order to get a clear picture on the number of patents and literature present to date relevant to inorganic material binding biomolecules and their applications, a thorough online search was conducted using national and worldwide databases. The literature search include standard bibliographic databases while patents included EPO Espacenet, WIPO patent scope, USPTO, Google patent search, Patent lens, etc. along with commercial databases such as Derwent and Patbase. Both English and American spellings were included in the searches. The initial number of patents found related to material binders were 981. After reading and excluding irrelevant patents such as organic binding peptides, works published before 2001, repeated patents, documents not in English etc., 51 highly relevant patents published from 2001 onwards were selected and analysed. These patents were further separated into six categories based on their target inorganic material and combinatorial library used. They include relevant patents on metal, metal oxide or combination binding peptides (19), magnetic and semiconductor binding peptides (8), carbon based (3), mineral (5), polymer (8) and other binders (9). Further, how these material specific binders have been used to synthesize simple to complex bio- or nano-materials, mediate the controlled biomineralization process, direct self-assembly and nanofabrication of ordered structures, facilitate the immobilization of functional biomolecules and construct inorganic-inorganic or organic-inorganic nano hybrids are concisely described. From analysis of recent literature and patents, we clearly show that biomimetic material binders are in the vanguard of new design approaches for novel nanomaterials with improved/ controlled physical and chemical properties that have no adverse effect on the structural or functional activities of the nanomaterials themselves. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  9. Single-layer nanosheets with exceptionally high and anisotropic hydroxyl ion conductivity

    PubMed Central

    Sun, Pengzhan; Ma, Renzhi; Bai, Xueyin; Wang, Kunlin; Zhu, Hongwei; Sasaki, Takayoshi

    2017-01-01

    When the dimensionality of layered materials is reduced to the physical limit, an ultimate two-dimensional (2D) anisotropy and/or confinement effect may bring about extraordinary physical and chemical properties. Layered double hydroxides (LDHs), bearing abundant hydroxyl groups covalently bonded within 2D host layers, have been proposed as inorganic anion conductors. However, typical hydroxyl ion conductivities for bulk or lamellar LDHs, generally up to 10−3 S cm−1, are considered not high enough for practical applications. We show that single-layer LDH nanosheets exhibited exceptionally high in-plane conductivities approaching 10−1 S cm−1, which were the highest among anion conductors and comparable to proton conductivities in commercial proton exchange membranes (for example, Nafion). The in-plane conductivities were four to five orders of magnitude higher than the cross-plane or cross-membrane values of restacked LDH nanosheets. This 2D superionic transport characteristic might have great promises in a variety of applications including alkaline fuel cells and water electrolysis. PMID:28439551

  10. Growth of aragonite calcium carbonate nanorods in the biomimetic anodic aluminum oxide template

    NASA Astrophysics Data System (ADS)

    Lee, Inho; Han, Haksoo; Lee, Sang-Yup

    2010-04-01

    In this study, a biomimetic template was prepared and applied for growing calcium carbonate (CaCO 3) nanorods whose shape and polymorphism were controlled. A biomimetic template was prepared by adsorbing catalytic dipeptides into the pores of an anodic aluminum oxide (AAO) membrane. Using this peptide-adsorbed template, mineralization and aggregation of CaCO 3 was carried out to form large nanorods in the pores. The nanorods were aragonite and had a structure similar to nanoneedle assembly. This aragonite nanorod formation was driven by both the AAO template and catalytic function of dipeptides. The AAO membrane pores promoted generation of aragonite polymorph and guided nanorod formation by guiding the nanorod growth. The catalytic dipeptides promoted the aggregation and further dehydration of calcium species to form large nanorods. Functions of the AAO template and catalytic dipeptides were verified through several control experiments. This biomimetic approach makes possible the production of functional inorganic materials with controlled shapes and crystalline structures.

  11. Micrometer-scale fabrication of complex three dimensional lattice + basis structures in silicon

    DOE PAGES

    Burckel, D. Bruce; Resnick, Paul J.; Finnegan, Patrick S.; ...

    2015-01-01

    A complementary metal oxide semiconductor (CMOS) compatible version of membrane projection lithography (MPL) for fabrication of micrometer-scale three-dimensional structures is presented. The approach uses all inorganic materials and standard CMOS processing equipment. In a single layer, MPL is capable of creating all 5 2D-Bravais lattices. Furthermore, standard semiconductor processing steps can be used in a layer-by-layer approach to create fully three dimensional structures with any of the 14 3D-Bravais lattices. The unit cell basis is determined by the projection of the membrane pattern, with many degrees of freedom for defining functional inclusions. Here we demonstrate several unique structural motifs, andmore » characterize 2D arrays of unit cells with split ring resonators in a silicon matrix. The structures exhibit strong polarization dependent resonances and, for properly oriented split ring resonators (SRRs), coupling to the magnetic field of a normally incident transverse electromagnetic wave, a response unique to 3D inclusions.« less

  12. Partitioning of Alkali Metal Salts and Boric Acid from Aqueous Phase into the Polyamide Active Layers of Reverse Osmosis Membranes.

    PubMed

    Wang, Jingbo; Kingsbury, Ryan S; Perry, Lamar A; Coronell, Orlando

    2017-02-21

    The partition coefficient of solutes into the polyamide active layer of reverse osmosis (RO) membranes is one of the three membrane properties (together with solute diffusion coefficient and active layer thickness) that determine solute permeation. However, no well-established method exists to measure solute partition coefficients into polyamide active layers. Further, the few studies that measured partition coefficients for inorganic salts report values significantly higher than one (∼3-8), which is contrary to expectations from Donnan theory and the observed high rejection of salts. As such, we developed a benchtop method to determine solute partition coefficients into the polyamide active layers of RO membranes. The method uses a quartz crystal microbalance (QCM) to measure the change in the mass of the active layer caused by the uptake of the partitioned solutes. The method was evaluated using several inorganic salts (alkali metal salts of chloride) and a weak acid of common concern in water desalination (boric acid). All partition coefficients were found to be lower than 1, in general agreement with expectations from Donnan theory. Results reported in this study advance the fundamental understanding of contaminant transport through RO membranes, and can be used in future studies to decouple the contributions of contaminant partitioning and diffusion to contaminant permeation.

  13. Methods for Introducing Inorganic Polymer Concepts throughout the Undergraduate Curriculum

    ERIC Educational Resources Information Center

    de Lill, Daniel T.; Carraher, Charles E., Jr.

    2017-01-01

    Inorganic polymers can be introduced in a variety of undergraduate courses to discuss concepts related to polymer chemistry. Inorganic polymers such as silicates and polysiloxanes are simple materials that can be incorporated into an introductory or descriptive inorganic course. Polymers based on inorganic carbon, including diamond and graphite,…

  14. Inorganic nanostructure-organic polymer heterostructures useful for thermoelectric devices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    See, Kevin C.; Urban, Jeffrey J.; Segalman, Rachel A.

    The present invention provides for an inorganic nanostructure-organic polymer heterostructure, useful as a thermoelectric composite material, comprising (a) an inorganic nanostructure, and (b) an electrically conductive organic polymer disposed on the inorganic nanostructure. Both the inorganic nanostructure and the electrically conductive organic polymer are solution-processable.

  15. Emerging of Inorganic Hole Transporting Materials For Perovskite Solar Cells.

    PubMed

    Rajeswari, Ramireddy; Mrinalini, Madoori; Prasanthkumar, Seelam; Giribabu, Lingamallu

    2017-07-01

    Hole transporting material (HTM) is a significant component to achieve the high performance perovskite solar cells (PSCs). Over the years, inorganic, organic and hybrid (organic-inorganic) material based HTMs have been developed and investigated successfully. Today, perovskite solar cells achieved the efficiency of 22.1 % with with 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenyl-amine) 9,9-spirobifluorene (spiro-OMeTAD) as HTM. Nevertheless, synthesis and cost of organic HTMs is a major challenging issue and therefore alternative materials are required. From the past few years, inorganic HTMs showed large improvement in power conversion efficiency (PCE) and stability. Recently CuO x reached the PCE of 19.0% with better stability. These developments affirms that inorganic HTMs are better alternativesto the organic HTMs for next generation PSCs. In this report, we mainly focussed on the recent advances of inorganic and hybrid HTMs for PSCs and highlighted the efficiency and stability of PSCs improved by changing metal oxides as HTMs. Consequently, we expect that energy levels of these inorganic HTMs matches very well with the valence band of perovskites and improved efficiency helps in future practical deployment of low cost PSCs. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Analytical electron microscopy of biogenic and inorganic carbonates

    NASA Technical Reports Server (NTRS)

    Blake, David F.

    1989-01-01

    In the terrestrial sedimentary environment, the mineralogically predominant carbonates are calcite-type minerals (rhombohedral carbonates) and aragonite-type minerals (orthorhombic carbonates). Most common minerals precipitating either inorganically or biogenically are high magnesium calcite and aragonite. High magnesium calcite (with magnesium carbonate substituting for more than 7 mole percent of the calcium carbonate) is stable only at temperatures greater than 700 C or thereabouts, and aragonite is stable only at pressures exceeding several kilobars of confining pressure. Therefore, these carbonates are expected to undergo chemical stabilization in the diagenetic environment to ultimately form stable calcite and dolomite. Because of the strong organic control of carbonate deposition in organisms during biomineralization, the microchemistry and microstructure of invertebrate skeletal material is much different than that present in inorganic carbonate cements. The style of preservation of microstructural features in skeletal material is therefore often quite distinctive when compared to that of inorganic carbonate even though wholesale recrystallization of the sediment has taken place. Microstructural and microchemical comparisons are made between high magnesium calcite echinoderm skeletal material and modern inorganic high magnesium calcite inorganic cements, using analytical electron microscopy and related techniques. Similar comparisons are made between analogous materials which have undergone stabilization in the diagenetic environment. Similar analysis schemes may prove useful in distinguishing between biogenic and inorganic carbonates in returned Martian carbonate samples.

  17. X-ray Reflectivity Characterization of Ion Distribution at Biomimetic Membrane Surfaces

    NASA Astrophysics Data System (ADS)

    Krüger, Peter; Pittler, Jens; Vaknin, David; Lösche, Mathias

    2003-03-01

    Ions at cell membrane surfaces may control the function and conformation of nearby biomolecules, thus playing an important role in inter- and intracellular transport as well as in biorecognition processes. Moreover, charge patterns at membrane surfaces may direct the growth of inorganic crystals in biomineralization. Langmuir monolayers are widely employed as model systems for studying charge distribution and growth processes at the organic/inorganic interface. We present a novel x-ray reflectivity technique that provides detailed information on ion distribution at biomembrane surfaces by using monochromatic x-rays at various energies at and away from the ion x-ray absorption edges. As a model, the interaction of Ba^2+ with DMPA^- (dimyristoyl phosphatidic acid) monolayers at the aqueous surface was studied. We find an unexpectedly large concentration of the cations near the interface where they form a Stern layer of bound ions. These studies have been complemented with conventional x-ray reflectivity measurements and extended to other anionic lipid species (DMPS, DMPG) and cations (Ca^2+).

  18. Towards All-Inorganic Transport Layers for Wide-Band-Gap Formamidinium Lead Bromide-Based Planar Photovoltaics

    DOE PAGES

    Subbiah, Anand S.; Mahuli, Neha; Agarwal, Sumanshu; ...

    2017-07-21

    Hybrid perovskite photovoltaic devices heavily rely on the use of organic (rather than inorganic) charge-transport layers on top of a perovskite absorber layer because of difficulties in depositing inorganic materials on top of these fragile absorber layers. However, in comparison to the unstable and expensive organic transport materials, inorganic charge-transport layers provide improved charge transport and stability to the device architecture. Here, we report photovoltaic devices using all-inorganic transport layers in a planar p-i-n junction device configuration using formamidinium lead tribromide (FAPbBr 3) as an absorber. Efficient planar devices are obtained through atomic layer deposition of nickel oxide and sputteredmore » zinc oxide as hole- and electron-transport materials, respectively. Using only inorganic charge-transport layers resulted in planar FAPbBr 3 devices with a power conversion efficiency of 6.75% at an open-circuit voltage of 1.23 V. In conclusion, the transition of planar FAPbBr 3 devices making from all-organic towards all-inorganic charge-transport layers is studied in detail.« less

  19. Towards All-Inorganic Transport Layers for Wide-Band-Gap Formamidinium Lead Bromide-Based Planar Photovoltaics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Subbiah, Anand S.; Mahuli, Neha; Agarwal, Sumanshu

    Hybrid perovskite photovoltaic devices heavily rely on the use of organic (rather than inorganic) charge-transport layers on top of a perovskite absorber layer because of difficulties in depositing inorganic materials on top of these fragile absorber layers. However, in comparison to the unstable and expensive organic transport materials, inorganic charge-transport layers provide improved charge transport and stability to the device architecture. Here, we report photovoltaic devices using all-inorganic transport layers in a planar p-i-n junction device configuration using formamidinium lead tribromide (FAPbBr 3) as an absorber. Efficient planar devices are obtained through atomic layer deposition of nickel oxide and sputteredmore » zinc oxide as hole- and electron-transport materials, respectively. Using only inorganic charge-transport layers resulted in planar FAPbBr 3 devices with a power conversion efficiency of 6.75% at an open-circuit voltage of 1.23 V. In conclusion, the transition of planar FAPbBr 3 devices making from all-organic towards all-inorganic charge-transport layers is studied in detail.« less

  20. Systematic evaluation of dissolved lead sorption losses to particulate syringe filter materials.

    PubMed

    Minning, Thomas; Lytle, Darren A; Pham, Maily; Kelty, Keith

    2015-06-01

    Distinguishing between soluble and particulate lead in drinking water is useful in understanding the mechanism of lead release and identifying remedial action. Typically, particulate lead is defined as the amount of lead removed by a 0.45-μm filter. Unfortunately, there is little guidance regarding selection of filter membrane material and little consideration to the possibility of the sorption of dissolved lead to the filter. The objective of this work was to examine the tendency of 0.45-μm syringe filter materials to adsorb lead. Tests were performed with water containing 40 and 24 μg/L soluble lead at pH 7 buffered with 50 mg C/L dissolved inorganic concentration (DIC). The amounts of lead sorbed greatly varied by filter, and only two filter types, polypropylene and mixed cellulose esters, performed well and are recommended. Great care must be taken in choosing a filter when filtering soluble lead and interpreting filter results.

  1. Correlating single-molecule and ensemble-average measurements of peptide adsorption onto different inorganic materials.

    PubMed

    Kim, Seong-Oh; Jackman, Joshua A; Mochizuki, Masahito; Yoon, Bo Kyeong; Hayashi, Tomohiro; Cho, Nam-Joon

    2016-06-07

    The coating of solid-binding peptides (SBPs) on inorganic material surfaces holds significant potential for improved surface functionalization at nano-bio interfaces. In most related studies, the goal has been to engineer peptides with selective and high binding affinity for a target material. The role of the material substrate itself in modulating the adsorption behavior of a peptide molecule remains less explored and there are few studies that compare the interaction of one peptide with different inorganic substrates. Herein, using a combination of two experimental techniques, we investigated the adsorption of a 16 amino acid-long random coil peptide to various inorganic substrates - gold, silicon oxide, titanium oxide and aluminum oxide. Quartz crystal microbalance-dissipation (QCM-D) experiments were performed in order to measure the peptide binding affinity for inorganic solid supports at the ensemble average level, and atomic force microscopy (AFM) experiments were conducted in order to determine the adhesion force of a single peptide molecule. A positive trend was observed between the total mass uptake of attached peptide and the single-molecule adhesion force on each substrate. Peptide affinity for gold was appreciably greater than for the oxide substrates. Collectively, the results obtained in this study offer insight into the ways in which inorganic materials can differentially influence and modulate the adhesion of SBPs.

  2. Redox-active Hybrid Materials for Pseudocapacitive Energy Storage

    NASA Astrophysics Data System (ADS)

    Boota, Muhammad

    Organic-inorganic hybrid materials show a great promise for the purpose of manufacturing high performance electrode materials for electrochemical energy storage systems and beyond. Molecular level combination of two best suited components in a hybrid material leads to new or sometimes exceptional sets of physical, chemical, mechanical and electrochemical properties that makes them attractive for broad ranges of applications. Recently, there has been growing interest in producing redox-active hybrid nanomaterials for energy storage applications where generally the organic component provides high redox capacitance and the inorganic component offers high conductivity and robust support. While organic-inorganic hybrid materials offer tremendous opportunities for electrochemical energy storage applications, the task of matching the right organic material out of hundreds of natural and nearly unlimited synthetic organic molecules to appropriate nanostructured inorganic support hampers their electrochemical energy storage applications. We aim to present the recent development of redox-active hybrid materials for pseudocapacitive energy storage. We will show the impact of combination of suitable organic materials with distinct carbon nanostructures and/or highly conductive metal carbides (MXenes) on conductivity, charge storage performance, and cyclability. Combined experimental and molecular simulation results will be discussed to shed light on the interfacial organic-inorganic interactions, pseudocapacitive charge storage mechanisms, and likely orientations of organic molecules on conductive supports. Later, the concept of all-pseudocapacitive organic-inorganic asymmetric supercapacitors will be highlighted which open up new avenues for developing inexpensive, sustainable, and high energy density aqueous supercapacitors. Lastly, future challenges and opportunities to further tailor the redox-active hybrids will be highlighted.

  3. Graded porous inorganic materials derived from self-assembled block copolymer templates.

    PubMed

    Gu, Yibei; Werner, Jörg G; Dorin, Rachel M; Robbins, Spencer W; Wiesner, Ulrich

    2015-03-19

    Graded porous inorganic materials directed by macromolecular self-assembly are expected to offer unique structural platforms relative to conventional porous inorganic materials. Their preparation to date remains a challenge, however, based on the sparsity of viable synthetic self-assembly pathways to control structural asymmetry. Here we demonstrate the fabrication of graded porous carbon, metal, and metal oxide film structures from self-assembled block copolymer templates by using various backfilling techniques in combination with thermal treatments for template removal and chemical transformations. The asymmetric inorganic structures display mesopores in the film top layers and a gradual pore size increase along the film normal in the macroporous sponge-like support structure. Substructure walls between macropores are themselves mesoporous, constituting a structural hierarchy in addition to the pore gradation. Final graded structures can be tailored by tuning casting conditions of self-assembled templates as well as the backfilling processes. We expect that these graded porous inorganic materials may find use in applications including separation, catalysis, biomedical implants, and energy conversion and storage.

  4. Enhanced Proton Conductivity of Sulfonated Hybrid Poly(arylene ether ketone) Membranes by Incorporating an Amino-Sulfo Bifunctionalized Metal-Organic Framework for Direct Methanol Fuel Cells.

    PubMed

    Ru, Chunyu; Li, Zhenhua; Zhao, Chengji; Duan, Yuting; Zhuang, Zhuang; Bu, Fanzhe; Na, Hui

    2018-03-07

    Novel side-chain-type sulfonated poly(arylene ether ketone) (SNF-PAEK) containing naphthalene and fluorine moieties on the main chain was prepared in this work, and a new amino-sulfo-bifunctionalized metal-organic framework (MNS, short for MIL-101-NH 2 -SO 3 H) was synthesized via a hydrothermal technology and postmodification. Then, MNS was incorporated into a SNF-PAEK matrix as an inorganic nanofiller to prepare a series of organic-inorganic hybrid membranes (MNS@SNF-PAEK-XX). The mechanical property, methanol resistance, electrochemistry, and other properties of MNS@SNF-PAEK-XX hybrid membranes were characterized in detail. We found that the mechanical strength and methanol resistances of these hybrid membranes were improved by the formation of an ionic cross-linking structure between -NH 2 of MNS and -SO 3 H on the side chain of SNF-PAEK. Particularly, the proton conductivity of these hybrid membranes increased obviously after the addition of MNS. MNS@SNF-PAEK-3% exhibited the proton conductivity of 0.192 S·cm -1 , which was much higher than those of the pristine membrane (0.145 S·cm -1 ) and recast Nafion (0.134 S·cm -1 ) at 80 °C. This result indicated that bifunctionalized MNS rearranged the microstructure of hybrid membranes, which could accelerate the transfer of protons. The hybrid membrane (MNS@SNF-PAEK-3%) showed a better direct methanol fuel cell performance with a higher peak power density of 125.7 mW/cm 2 at 80 °C and a higher open-circuit voltage (0.839 V) than the pristine membrane.

  5. Robust Fluorine-Free Superhydrophobic Amino-Silicone Oil/SiO2 Modification of Electrospun Polyacrylonitrile Membranes for Waterproof-Breathable Application.

    PubMed

    Sheng, Junlu; Xu, Yue; Yu, Jianyong; Ding, Bin

    2017-05-03

    Superhydrophobic waterproof-breathable membranes have attracted considerable interest owing to their multifunctional applications in self-cleaning, anti-icing, anticorrosion, outdoor tents, and protective clothing. Despite the researches pertaning to the construction of superhydrophobic functional membranes by nanoparticle finishing have increased drastically, the disconnected particle component is easy to fall off from the membranes under deformation and wear conditions, which has restricted their wide use in practice. Here, robust superhydrophobic microporous membranes were prepared via a facile and environmentally friendly strategy by dip-coating amino-silicone oil (ASO) onto the electrospun polyacrylonitrile (PAN) membranes, followed by SiO 2 nanoparticles (SiO 2 NPs) blade coating. Compared with hydrophilic PAN membranes, the modified membranes exhibited superhydrophobic surface with an advancing water contact angle up to 156°, after introducing ASO as low surface energy substance and SiO 2 NPs as filler to reduce the pore size and construct the multihierarchical rough structure. Varying the concentrations of ASO and SiO 2 NPs systematically, the PAN electrospun membranes modified with 1 wt % ASO and 0.1 wt % SiO 2 NPs were endowed with good water-resistance (74.3 kPa), relative low thermal conductivity (0.0028 W m -1 K -1 ), modest vapor permeability (11.4 kg m -2 d -1 ), and air permeability (20.5 mm s -1 ). Besides, the inorganic-organic hybrid coating of ASO/SiO 2 NPs could maintain its superhydrophobicity even after 40 abrasion cycles. The resulting membranes were found to resist variations on the pH scale from 0 to 12, and retained their water repellent properties when exposed to harsh acidic and alkali conditions. This facile fabrication of durable fluorine-free superhydrophobic membranes simultaneous with good waterproof-breathable performance provides the advantages for potential applications in self-cleaning materials and versatile protective clothing.

  6. Structure and magnetic properties of SiO{sub 2}/PCL novel sol–gel organic–inorganic hybrid materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Catauro, Michelina, E-mail: michelina.catauro@unina2.it; Bollino, Flavia; Cristina Mozzati, Maria

    2013-07-15

    Organic–inorganic nanocomposite materials have been synthesized via sol–gel. They consist of an inorganic SiO{sub 2} matrix, in which different percentages of poly(ε-caprolactone) (PCL) have been incorporated. The formation of H-bonds among the carbonyl groups of the polymer chains and Si–OH group of the inorganic matrix has been proved by means of Fourier transform infrared spectroscopy (FT-IR) analysis and has been confirmed by solid-state nuclear magnetic resonance (NMR). X-Ray diffraction (XRD) analysis highlighted the amorphous nature of the synthesized materials. Scanning electron microscope (SEM) micrograph and atomic force microscope (AFM) topography showed their homogeneous morphology and nanostructure nature. Considering the opportunitymore » to synthesize these hybrid materials under microgravity conditions by means of magnetic levitation, superconducting quantum interference device (SQUID) magnetometry has been used to quantify their magnetic susceptibility. This measure has shown that the SiO{sub 2}/PCL hybrid materials are diamagnetic and that their diamagnetic susceptibility is independent of temperature and increases with the PCL amount. - Graphical abstract: Characterization and magnetic properties of SiO{sub 2}/PCL organic–inorganic hybrid materials synthesized via sol–gel. FT-IR, Fourier transform infrared spectroscopy; solid-state NMR: solid-state nuclear magnetic resonance; SQUID: superconducting quantum interference device. - Highlights: • Sol–gel synthesis of SiO{sub 2}/PCL amorphous class I organic–inorganic hybrid materials. • FT-IR and NMR analyses show the hydrogen bonds formation between SiO{sub 2} and PCL. • AFM and SEM analyses confirm that the SiO{sub 2}/PCL are homogenous hybrid materials. • The SQUID measures show that the simples are diamagnetic. • Diamagnetic susceptibility of SiO{sub 2}/PCL materials increases with the PCL amount.« less

  7. Gas separation by composite solvent-swollen membranes

    DOEpatents

    Matson, S.L.; Lee, E.K.L.; Friesen, D.T.; Kelly, D.J.

    1989-04-25

    There is disclosed a composite immobilized liquid membrane of a solvent-swollen polymer and a microporous organic or inorganic support, the solvent being at least one highly polar solvent containing at least one nitrogen, oxygen, phosphorus or sulfur atom, and having a boiling point of at least 100 C and a specified solubility parameter. The solvent or solvent mixture is homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. The membrane is suitable for acid gas scrubbing and oxygen/nitrogen separation. 3 figs.

  8. Gas separation by composite solvent-swollen membranes

    DOEpatents

    Matson, Stephen L.; Lee, Eric K. L.; Friesen, Dwayne T.; Kelly, Donald J.

    1989-01-01

    There is disclosed a composite immobulized liquid membrane of a solvent-swollen polymer and a microporous organic or inorganic support, the solvent being at least one highly polar solvent containing at least one nitrogen, oxygen, phosphorous or sulfur atom, and having a boiling point of at least 100.degree. C. and a specified solubility parameter. The solvent or solvent mixture is homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. The membrane is suitable for acid gas scrubbing and oxygen/nitrogen separation.

  9. Critical aspects in the production of periodically ordered mesoporous titania thin films.

    PubMed

    Soler-Illia, Galo J A A; Angelomé, Paula C; Fuertes, M Cecilia; Grosso, David; Boissiere, Cedric

    2012-04-21

    Periodically ordered mesoporous titania thin films (MTTF) present a high surface area, controlled porosity in the 2-20 nm pore diameter range and an amorphous or crystalline inorganic framework. These materials are nowadays routinely prepared by combining soft chemistry and supramolecular templating. Photocatalytic transparent coatings and titania-based solar cells are the immediate promising applications. However, a wealth of new prospective uses have emerged on the horizon, such as advanced catalysts, perm-selective membranes, optical materials based on plasmonics and photonics, metamaterials, biomaterials or new magnetic nanocomposites. Current and novel applications rely on the ultimate control of the materials features such as pore size and geometry, surface functionality and wall structure. Even if a certain control of these characteristics has been provided by the methods reported so far, the needs for the next generation of MTTF require a deeper insight in the physical and chemical processes taking place in their preparation and processing. This article presents a critical discussion of these aspects. This discussion is essential to evolve from know-how to sound knowledge, aiming at a rational materials design of these fascinating systems.

  10. Polyethersulfone - barium chloride blend ultrafiltration membranes for dye removal studies

    NASA Astrophysics Data System (ADS)

    Rambabu, K.; Srivatsan, N.; Gurumoorthy, Anand V. P.

    2017-11-01

    A series of Polyethersulfone (PES) - barium chloride (BaCl2) blend ultra filtration membrane was developed by varying the BaCl2 concentration in the dope solution. Prepared membranes were subjected to membrane characterization and their performance was studied through dye rejection tests. Morphological studies through SEM and AFM showed that the composite membranes exhibited differences in morphologies, porosities and properties due to the BaCl2 addition as compared with pristine PES membrane. Addition of the inorganic modifier enhanced the hydrophilicity and water permeability of the blend membrane system. Polymer enhanced ultrafiltration of dye solutions showed that the proposed blend system had better performance in terms of flux and rejection efficiency than the pure polymer membrane. The performance of the 2 wt% BaCl2 blend membrane was more promising for application to real time dye wastewater studies.

  11. Engineering nanomaterials with a combined electrochemical and molecular biomimetic approach

    NASA Astrophysics Data System (ADS)

    Dai, Haixia

    Biocomposite materials, such as bones, teeth, and shells, are created using mild aqueous solution-based processes near room temperature. Proteins add flexibility to these processes by facilitating the nucleation, growth, and ordering of specific inorganic materials into hierarchical structures. We aim to develop a biomimetic strategy for engineering technologically relevant inorganic materials with controlled compositions and structures, as Nature does, using proteins to orchestrate material formation and assembly. This approach involves three basic steps: (i) preparation of inorganic substrates compatible with combinatorial polypeptide screening; (ii) identification of inorganic-binding polypeptides and their engineering into inorganic-binding proteins; and (iii) protein-mediated inorganic nucleation and organization. Cuprous oxide (Cu2O), a p-type semiconductor, has been used to demonstrate all three steps. Zinc oxide (ZnO), an n-type semiconductor, has been used to show the generality of selected steps. Step (i), preparation of high quality inorganic substrates to select inorganic-binding polypeptides, was accomplished using electrochemical microfabrication to grow and pattern Cu2O and ZnO. Raman spectroscopy and x-ray photoelectron spectroscopy were used to verify phase purity and compositional stability of these surfaces during polypeptide screening. Step (ii), accomplished in collaboration with personnel in Prof Baneyx' lab at the University of Washington, involved incubating the inorganic substrates with the FliTrx(TM) random peptide library to identify cysteine-constrained dodecapeptides that bind the targeted inorganic. Insertion of a Cu2O-binding dodecapeptide into the DNA-binding protein TraI endowed the engineered TraI with strong affinity for Cu2O (Kd ≈ 10 -8 M). Finally, step (iii) involved nonequilibrium synthesis and organization of Cu2O nanoparticles, taking advantage of the inorganic and DNA recognition properties of the engineered TraI. The high affinity of the engineered TraI for Cu2O over other related copper compounds led to the formation of Cu2O nanoparticles from a cuprous chloride complex (Cu2Cln1-n, n = 2 or 3) electrolyte under conditions where the mineral atacamite (CuCl(OH) 3) is thermodynamically preferred. The nonequilibrium Cu 2O nanoparticles consisted of 2--3 nm Cu2O cores and functional protein shells that enabled predictable meso-scale assembly on DNA templates. In short, we have rationally designed a protein-based scheme for forming and organizing inorganic materials that Nature has not previous worked with.

  12. Bio-inspired materials for electrochemical devices

    NASA Astrophysics Data System (ADS)

    Pawlicka, A.; Firmino, A.; Sentanin, F.; Sabadini, R. C.; Jimenez, D. E. Q.; Jayme, C. C.; Mindroiu, M.; Zgarian, R. G.; Tihan, G. T.; Rau, I.; Silva, M. M.; Nogueira, A. F.; Kanicki, J.; Kajzar, F.

    2015-10-01

    Natural macromolecules are very promising row materials to be used in modern technology including security and defense. They are abundant in nature, easy to extract and possess biocompatibility and biodegradability properties. These materials can be modified throughout chemical or physical processes, and can be doped with lithium and rare earth salts, ionic liquids, organic and inorganic acids. In this communication samples of DNA and modified DNA were doped with Prussian Blue (PB), poly(ethylene dioxythiophene) (PEDOT), europium and erbium triflate and organic dyes such as Nile Blue (NB), Disperse Red 1 (DR1) and Disperse Orange 3 (DO3). The colored or colorless membranes were characterized by electrochemical and spectroscopic measurements, and they were applied in electrochromic devices (ECDs) and dye sensitized solar cells (DSSC). ECDs change the color under applied potential, so they can modulate the intensity of transmitted light of 15 to 35%. As the electrochromic materials, WO3 or Prussian blue (PB), are usually blue colored, the color change is from transparent to blue. DNA, and the complexes: DNA-CTMA, DNA-DODA and DNAPEDOT: PSS were also investigated as either hole carrier material (HTM) or polymer electrolyte in dye-sensitized solar cells (DSSC). The DNA-based samples as HTM in small DSSCs revealed a solar energy conversion efficiency of 0.56%. Polymer electrolytes of DNA-CTMA and DNA-DODA, both with 10 wt% of LiI/I2, applied in small DSSC, exhibited the efficiencies of 0.18 and 0.66%, respectively. The obtained results show that natural macromolecules-based membranes are not only environmentally friendly but are also promising materials to be investigated for several electrochemical devices. However, to obtain better performances more research is still needed.

  13. Measurements needed for on-line control of retention and drainage

    Treesearch

    Allan M. Springer; Jeffrey S. Noe; T. H. Wegner

    1987-01-01

    In a retention and drainage control strategy, it is necessary to monitor the concentration of dissolved inorganic material and the concentration of dissolved and colloidal organic material. Conductivity is successful as a sensor to monitor inorganic material. We studied TOC as a means to monitor dissolved and colloidal organic material and found it to work well. Both...

  14. Inorganic nanolayers: structure, preparation, and biomedical applications.

    PubMed

    Saifullah, Bullo; Hussein, Mohd Zobir B

    2015-01-01

    Hydrotalcite-like compounds are two-dimensional inorganic nanolayers also known as clay minerals or anionic clays or layered double hydroxides/layered hydroxy salts, and have emerged as a single type of material with numerous biomedical applications, such as drug delivery, gene delivery, cosmetics, and biosensing. Inorganic nanolayers are promising materials due to their fascinating properties, such as ease of preparation, ability to intercalate different type of anions (inorganic, organic, biomolecules, and even genes), high thermal stability, delivery of intercalated anions in a sustained manner, high biocompatibility, and easy biodegradation. Inorganic nanolayers have been the focus for researchers over the last decade, resulting in widening application horizons, especially in the field of biomedical science. These nanolayers have been widely applied in drug and gene delivery. They have also been applied in biosensing technology, and most recently in bioimaging science. The suitability of inorganic nanolayers for application in drug delivery, gene delivery, biosensing technology, and bioimaging science makes them ideal materials to be applied for theranostic purposes. In this paper, we review the structure, methods of preparation, and latest advances made by inorganic nanolayers in such biomedical applications as drug delivery, gene delivery, biosensing, and bioimaging.

  15. Inorganic nanolayers: structure, preparation, and biomedical applications

    PubMed Central

    Saifullah, Bullo; Hussein, Mohd Zobir B

    2015-01-01

    Hydrotalcite-like compounds are two-dimensional inorganic nanolayers also known as clay minerals or anionic clays or layered double hydroxides/layered hydroxy salts, and have emerged as a single type of material with numerous biomedical applications, such as drug delivery, gene delivery, cosmetics, and biosensing. Inorganic nanolayers are promising materials due to their fascinating properties, such as ease of preparation, ability to intercalate different type of anions (inorganic, organic, biomolecules, and even genes), high thermal stability, delivery of intercalated anions in a sustained manner, high biocompatibility, and easy biodegradation. Inorganic nanolayers have been the focus for researchers over the last decade, resulting in widening application horizons, especially in the field of biomedical science. These nanolayers have been widely applied in drug and gene delivery. They have also been applied in biosensing technology, and most recently in bioimaging science. The suitability of inorganic nanolayers for application in drug delivery, gene delivery, biosensing technology, and bioimaging science makes them ideal materials to be applied for theranostic purposes. In this paper, we review the structure, methods of preparation, and latest advances made by inorganic nanolayers in such biomedical applications as drug delivery, gene delivery, biosensing, and bioimaging. PMID:26366081

  16. Chemical cleaning/disinfection and ageing of organic UF membranes: a review.

    PubMed

    Regula, C; Carretier, E; Wyart, Y; Gésan-Guiziou, G; Vincent, A; Boudot, D; Moulin, P

    2014-06-01

    Membrane separation processes have become a basic unit operation for process design and product development. These processes are used in a variety of separation and concentration steps, but in all cases, the membranes must be cleaned regularly to remove both organic and inorganic material deposited on the surface and/or into the membrane bulk. Cleaning/disinfection is a vital step in maintaining the permeability and selectivity of the membrane in order to get the plant to its original capacity, to minimize risks of bacteriological contamination, and to make acceptable products. For this purpose, a large number of chemical cleaning/disinfection agents are commercially available. In general, these cleaning/disinfection agents have to improve the membrane flux to a certain extent. However, they can also cause irreversible damages in membrane properties and performances over the long term. Until now, there is considerably less literature dedicated to membrane ageing than to cleaning/disinfection. The knowledge in cleaning/disinfection efficiency has recently been improved. But in order to develop optimized cleaning/disinfection protocols there still remains a challenge to better understand membrane ageing. In order to compensate for the lack of correlated cleaning/disinfection and ageing data from the literature, this paper investigates cleaning/disinfection efficiencies and ageing damages of organic ultrafiltration membranes. The final aim is to provide less detrimental cleaning/disinfection procedures and to propose some guidelines which should have been taken into consideration in term of membrane ageing studies. To carry out this study, this article will detail the background of cleaning/disinfection and aging membrane topics in a first introductive part. In a second part, key factors and endpoints of cleaning/disinfection and aging membranes will be discussed deeply: the membrane role and the cleaning parameters roles, such as water quality, storing conditions, cleaning/disinfection/aging agents/conditions/protocols. The third and last part will be developed the parameters, methods and ways of characterization at our disposal and commonly used to develop and implement membrane cleaning and/or ageing studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Soft templating strategies for the synthesis of mesoporous materials: inorganic, organic-inorganic hybrid and purely organic solids.

    PubMed

    Pal, Nabanita; Bhaumik, Asim

    2013-03-01

    With the discovery of MCM-41 by Mobil researchers in 1992 the journey of the research on mesoporous materials started and in the 21st century this area of scientific investigation have extended into numerous branches, many of which contribute significantly in emerging areas like catalysis, energy, environment and biomedical research. As a consequence thousands of publications came out in large varieties of national and international journals. In this review, we have tried to summarize the published works on various synthetic pathways and formation mechanisms of different mesoporous materials viz. inorganic, organic-inorganic hybrid and purely organic solids via soft templating pathways. Generation of nanoscale porosity in a solid material usually requires participation of organic template (more specifically surfactants and their supramolecular assemblies) called structure-directing agent (SDA) in the bottom-up chemical reaction process. Different techniques employed for the syntheses of inorganic mesoporous solids, like silicas, metal doped silicas, transition and non-transition metal oxides, mixed oxides, metallophosphates, organic-inorganic hybrids as well as purely organic mesoporous materials like carbons, polymers etc. using surfactants are depicted schematically and elaborately in this paper. Moreover, some of the frontline applications of these mesoporous solids, which are directly related to their functionality, composition and surface properties are discussed at the appropriate places. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Investigations of inorganic and organic fouling behaviors, antifouling and cleaning strategies for pressure retarded osmosis (PRO) membrane using seawater desalination brine and wastewater.

    PubMed

    Han, Gang; Zhou, Jieliang; Wan, Chunfeng; Yang, Tianshi; Chung, Tai-Shung

    2016-10-15

    By employing seawater desalination brine (SWBr) and wastewater brine (WWBr) as the feed pair, membrane fouling behaviors as well as antifouling and cleaning strategies for the state-of-the-art thin-film composite polyethersulfone (TFC-PES) hollow fiber membrane have been systematically investigated under pressure retarded osmosis (PRO) operations. Fouling on the polyamide selective layer induced by the SWBr draw solution is relatively mild because of the outstanding membrane rejection and the hydration antifouling layer formed by the permeating water. However, using WWBr as the feed causes fast and severe internal concentration polarization (ICP) and fouling within the porous PES substrate, which result in dramatic flux and power density declines. In addition, the PRO fouling upon and within the porous substrate is highly irreversible. Experimental data show that both anti-scalant pretreatment and pH adjustment of WWBr could effectively mitigate inorganic fouling, while increasing feed flow velocity along the substrate surface is ineffective for fouling control. To clean the fouled membranes, hydraulic-pressure induced backwash and flushing with alkaline and NaOCl solutions on the fouled surface are effective strategies to remove foulants and regenerate membranes with a flux recovery of 83-90%. However, osmotic backwash shows low cleaning efficiency in PRO. In summary, a proper combination of feed pretreatment and membrane cleaning strategies has been demonstrated in this study to sustain PRO operations with a high water flux and power density. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Membrane-bound 2,3-diphosphoglycerate phosphatase of human erythrocytes.

    PubMed

    Schröter, W; Neuvians, M

    1970-12-01

    Gradual osmotic hemolysis of human erythrocytes reduces the cell content of whole protein, hemoglobin, 2,3-diphosphoglycerate and triosephosphate isomerase extensively, but not that of membrane protein and 2,3-diphosphoglycerate phosphatase. After the refilling of the ghosts with 2,3-diphosphoglycerate and reconstitution of the membrane, the 2,3-diphosphoglycerate phosphatase activity equals that of intact red cells. The membrane-bound 2,3-diphosphoglycerate phosphatase can be activated by sodium hyposulfite. The enzyme system of ghosts seems to differ from that of intact red cells with regard to the optima of pH and temperature. It remains to be elucidated if the membrane binding of the 2,3-diphosphoglycerate phosphatase is related to the transfer of inorganic phosphate across the red cell membrane.

  20. Interfacial and Surface Science | Materials Science | NREL

    Science.gov Websites

    -flight SIMS (TOF-SIMS) provides surface spectroscopy of both inorganic and organic materials, and is Chamber This tool enables deposition of inorganic chalcogenides and for basic material and device studies lead halide perovskites and semiconductor quantum dots. Contact: Craig Perkins | Email | 303-384-6659

  1. Process simulation and economic analysis of biodiesel production from waste cooking oil with membrane bioreactor

    NASA Astrophysics Data System (ADS)

    Abdurakhman, Yuanita Budiman; Putra, Zulfan Adi; Bilad, Muhammad Roil

    2017-10-01

    Pollution and shortage of clean energy supply are among major problems that are caused by rapid population growth. Due to this growth, waste cooking oil is one of the pollution sources. On the other hand, biodiesel appears to be one of the most promising and feasible energy sources as it emits less toxic pollutants and greenhouse gases than petroleum diesel. Thus, biodiesel production using waste cooking oil offers a two-in-one solution to cater pollution and energy issues. However, the conventional biodiesel production process using homogeneous base catalyst and stirred tank reactor is unable to produce high purity of biodiesel from waste cooking oil. It is due its sensitivity to free fatty acid (FFA) content in waste cooking oil and purification difficulties. Therefore, biodiesel production using heterogeneous acid catalyst in membrane reactor is suggested. The product of this process is fatty acid methyl esters (FAME) or biodiesel with glycerol as by-product. This project is aimed to study techno-economic feasibility of biodiesel production from waste cooking oil via heterogeneous acid catalyst in membrane reactor. Aspen HYSYS is used to accomplish this aim. Several cases, such as considering different residence times and the production of pharmaceutical (USP) grade glycerol, are evaluated and compared. Economic potential of these cases is calculated by considering capital expenditure, utilities cost, product and by-product sales, as well as raw material costs. Waste cooking oil, inorganic pressure-driven membrane and WAl is used as raw material, type of membrane and heterogeneous acid catalyst respectively. Based on literature data, FAME yield formulation is developed and used in the reactor simulation. Simulation results shows that economic potential increases by 30% if pharmaceutical (USP) grade glycerol is produced regardless the residence time of the reactor. In addition, there is no significant effect of residence time on the economic potential.

  2. Development of inorganic resists for electron beam lithography: Novel materials and simulations

    NASA Astrophysics Data System (ADS)

    Jeyakumar, Augustin

    Electron beam lithography is gaining widespread utilization as the semiconductor industry progresses towards both advanced optical and non-optical lithographic technologies for high resolution patterning. The current resist technologies are based on organic systems that are imaged most commonly through chain scission, networking, or a chemically amplified polarity change in the material. Alternative resists based on inorganic systems were developed and characterized in this research for high resolution electron beam lithography and their interactions with incident electrons were investigated using Monte Carlo simulations. A novel inorganic resist imaging scheme was developed using metal-organic precursors which decompose to form metal oxides upon electron beam irradiation that can serve as inorganic hard masks for hybrid bilayer inorganic-organic imaging systems and also as directly patternable high resolution metal oxide structures. The electron beam imaging properties of these metal-organic materials were correlated to the precursor structure by studying effects such as interactions between high atomic number species and the incident electrons. Optimal single and multicomponent precursors were designed for utilization as viable inorganic resist materials for sub-50nm patterning in electron beam lithography. The electron beam imaging characteristics of the most widely used inorganic resist material, hydrogen silsesquioxane (HSQ), was also enhanced using a dual processing imaging approach with thermal curing as well as a sensitizer catalyzed imaging approach. The interaction between incident electrons and the high atomic number species contained in these inorganic resists was also studied using Monte Carlo simulations. The resolution attainable using inorganic systems as compared to organic systems can be greater for accelerating voltages greater than 50 keV due to minimized lateral scattering in the high density inorganic systems. The effects of loading nanoparticles in an electron beam resist was also investigated using a newly developed hybrid Monte Carlo approach that accounts for multiple components in a solid film. The resolution of the nanocomposite resist process was found to degrade with increasing nanoparticle loading. Finally, the electron beam patterning of self-assembled monolayers, which were found to primarily utilize backscattered electrons from the high atomic number substrate materials to form images, was also investigated and characterized. It was found that backscattered electrons limit the resolution attainable at low incident electron energies.

  3. A Splash to Nano-Sized Inorganic Energy-Materials by the Low-Temperature Molecular Precursor Approach.

    PubMed

    Driess, Matthias; Panda, Chakadola; Menezes, Prashanth Wilfried

    2018-05-07

    The low-temperature synthesis of inorganic materials and their interfaces at the atomic and molecular level provides numerous opportunities for the design and improvement of inorganic materials in heterogeneous catalysis for sustainable chemical energy conversion or other energy-saving areas. Using suitable molecular precursors for functional inorganic nanomaterial synthesis allows for facile control over uniform particle size distribution, stoichiometry, and leads to desired chemical and physical properties. This minireview outlines some advantages of the molecular precursor approach in light of selected recent developments of molecule-to-nanomaterials synthesis for renewable energy applications, relevant for the oxygen evolution reaction (OER), hydrogen evolution reaction (HER) and overall water-splitting. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Screening combinatorial arrays of inorganic materials with spectroscopy or microscopy

    DOEpatents

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    2004-02-03

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  5. Preparation and screening of crystalline inorganic materials

    DOEpatents

    Schultz, Peter G [La Jolla, CA; Xiang, Xiaodong [Danville, CA; Goldwasser, Isy [Palo Alto, CA; Brice{hacek over }o, Gabriel; Sun, Xiao-Dong [Fremont, CA; Wang, Kai-An [Cupertino, CA

    2008-10-28

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  6. Combinatorial screening of inorganic and organometallic materials

    DOEpatents

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    2002-01-01

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  7. Release of mitochondrial glutathione and calcium by a cyclosporin A-sensitive mechanism occurs without large amplitude swelling.

    PubMed

    Savage, M K; Reed, D J

    1994-11-15

    Treatment of isolated mitochondria with calcium and inorganic phosphate induces inner membrane permeability that is thought to be mediated through a non-selective, calcium-dependent pore. The inner membrane permeability results in the rapid efflux of small matrix solutes such as glutathione and calcium, loss of coupled functions, and large amplitude swelling. We have identified conditions of permeability transition without large amplitude swelling, a parameter often used to assess inner membrane permeability. The addition of either oligomycin, antimycin, or sulfide to incubation buffer containing calcium and inorganic phosphate abolished large-amplitude swelling of mitochondria but did not prevent inner membrane permeability as demonstrated by the release of mitochondrial glutathione and calcium. The release of both glutathione and calcium was inhibited by the addition of cyclosporin A, a potent inhibitor of permeability transition. Transmission electron microscopy analysis, combined with the glutathione and calcium release data, indicate that permeability transition can be observed in the absence of large-amplitude swelling. Permeability transition occurring both with and without large-amplitude swelling was accompanied by a collapse of the membrane potential. We conclude that cyclosporin A-sensitive permeability transition can occur without obvious morphological changes such as large-amplitude swelling. Monitoring the cyclosporin A-sensitive release of concentrated endogenous matrix solutes, such as GSH, may be a sensitive and useful indicator of permeability transition.

  8. Mechanism of action of anions on the electron transport chain in thylakoid membranes of higher plants.

    PubMed

    Singh-Rawal, Pooja; Zsiros, Ottó; Bharti, Sudhakar; Garab, Gyozo; Jajoo, Anjana

    2011-04-01

    With an aim to improve our understanding of the mechanisms behind specific anion effects in biological membranes, we have studied the effects of sodium salts of anions of varying valency in thylakoid membranes. Rates of electron transport of PS II and PS I, 77K fluorescence emission and excitation spectra, cyclic electron flow around PS I and circular dichroism (CD) spectra were measured in thylakoid membranes in order to elucidate a general mechanism of action of inorganic anions on photosynthetic electron transport chain. Re-distribution of absorbed excitation energy has been observed as a signature effect of inorganic anions. In the presence of anions, such as nitrite, sulphate and phosphate, distribution of absorbed excitation energy was found to be more in favor of Photosystem I (PS I). The amount of energy distributed towards PS I depended on the valency of the anion. In this paper, we propose for the first time that energy re-distribution and its valence dependence may not be the effect of anions per se. The entry of negative charge (anion) is accompanied by influx of positive charge (protons) to maintain a balance of charge across the thylakoid membranes. As reflected by the CD spectra, the observed energy re-distribution could be a result of structural rearrangements of the protein complexes of PS II caused by changes in the ionic environment of the thylakoid lumen.

  9. Biomineralization of unicellular organisms: an unusual membrane biochemistry for the production of inorganic nano- and microstructures.

    PubMed

    Bäuerlein, Edmund

    2003-02-10

    With evolution, Nature has ingeniously succeeded in giving rise to an impressive variety of inorganic structures. Every organism that synthesizes biogenic minerals does so in a form that is unique to that species. This biomineralization is apparently biologically controlled. It is thus expected that both the synthesis and the form of every specific biogenic mineral is genetically determined and controlled. An investigation of the mechanism of biomineralization has only become possible with the development of modern methods in molecular biology. Unicellular organisms such as magnetic bacteria, calcareous algae, and diatoms, all of which are amongst the simplest forms of life, are particularly suited to be investigated by these methods. Crystals and composites of proteins and amorphous inorganic polymers are formed as complex structures within these organisms; these structures are not known in conventional inorganic chemistry.

  10. Inorganic fullerenes and nanotubes: Wealth of materials and morphologies

    NASA Astrophysics Data System (ADS)

    Bar-Sadan, M.; Kaplan-Ashiri, I.; Tenne, R.

    2007-10-01

    It is already well established today that numerous materials form closed-cage structures, of which carbon fullerenes and nanotubes are a special case [1]. Inorganic fullerene-like nanoparticles (designated IF) and inorganic nanotubes (INT) have been produced by different routes and experimental techniques, achieving persistent growth of a variety of materials and structural wealth within them. The research in this area has focused on synthesizing new IF and INT materials and understanding their different properties as well as scaling up the synthetic process in order to make it suitable for industrial applications. In this review, the main synthetic procedures to obtain inorganic fullerene-like nanoparticles and nanotubes will be discussed alongside with the different mechanisms that affect the morphology of the final product. The main differences between the morphologies will be presented. Some general considerations relating the properties of the parent compound with the morphology of the product will be mentioned.

  11. Vectorial Biochemistry

    ERIC Educational Resources Information Center

    Bowne, S. W., Jr.; Bowne, G. D.

    1975-01-01

    Describes a biochemical concept called Mitchell's chemiosmotic hypothesis, which proposes a system that catalyzes the hydrolysis of ATP to ADP and inorganic phosphate. The system is reversible and causes a translocation of protons across a physiological membrane. (MLH)

  12. Coupling pervaporation to AAS for inorganic and organic mercury determination. A new approach to speciation of Hg in environmental samples.

    PubMed

    Fernandez-Rivas, C; Muñoz-Olivas, R; Camara, C

    2001-12-01

    The design and development of a new approach for Hg speciation in environmental samples is described in detail. This method, consisting of the coupling of pervaporation and atomic absorption spectrometry, is based on a membrane phenomenon that combines the evaporation of volatile analytes and their diffusion through a polymeric membrane. It is proposed here as an alternative to gas chromatography for speciation of inorganic and organic Hg compounds, as the latter compounds are volatile and can be separated by applying the principles mentioned above. The interest of this method lies in its easy handling, low cost, and rapidity for the analysis of liquid and solid samples. This method has been applied to Hg speciation in a compost sample provided by a waste water treatment plant.

  13. Hybrid Solar Cells: Materials, Interfaces, and Devices

    NASA Astrophysics Data System (ADS)

    Mariani, Giacomo; Wang, Yue; Kaner, Richard B.; Huffaker, Diana L.

    Photovoltaic technologies could play a pivotal role in tackling future fossil fuel energy shortages, while significantly reducing our carbon dioxide footprint. Crystalline silicon is pervasively used in single junction solar cells, taking up 80 % of the photovoltaic market. Semiconductor-based inorganic solar cells deliver relatively high conversion efficiencies at the price of high material and manufacturing costs. A great amount of research has been conducted to develop low-cost photovoltaic solutions by incorporating organic materials. Organic semiconductors are conjugated hydrocarbon-based materials that are advantageous because of their low material and processing costs and a nearly unlimited supply. Their mechanical flexibility and tunable electronic properties are among other attractions that their inorganic counterparts lack. Recently, collaborations in nanotechnology research have combined inorganic with organic semiconductors in a "hybrid" effort to provide high conversion efficiencies at low cost. Successful integration of these two classes of materials requires a profound understanding of the material properties and an exquisite control of the morphology, surface properties, ligands, and passivation techniques to ensure an optimal charge carrier generation across the hybrid device. In this chapter, we provide background information of this novel, emerging field, detailing the various approaches for obtaining inorganic nanostructures and organic polymers, introducing a multitude of methods for combining the two components to achieve the desired morphologies, and emphasizing the importance of surface manipulation. We highlight several studies that have fueled new directions for hybrid solar cell research, including approaches for maximizing efficiencies by controlling the morphologies of the inorganic component, and in situ molecular engineering via electrochemical polymerization of a polymer directly onto the inorganic nanowire surfaces. In the end, we provide some possible future directions for advancing the field, with a focus on flexible, lightweight, semitransparent, and low-cost photovoltaics.

  14. Flexible bipolar nanofibrous membranes for improving gradient microstructure in tendon-to-bone healing.

    PubMed

    Li, Xiaoxi; Cheng, Ruoyu; Sun, Zhiyong; Su, Wei; Pan, Guoqing; Zhao, Song; Zhao, Jinzhong; Cui, Wenguo

    2017-10-01

    Enthesis is a specialized tissue interface between the tendon and bone. Enthesis structure is very complex because of gradient changes in its composition and structure. There is currently no strategy to create a suitable environment and to regenerate the gradual-changing enthesis because of the modular complexities between two tissue types. Herein, a dual-layer organic/inorganic flexible bipolar fibrous membrane (BFM) was successfully fabricated by electrospinning to generate biomimetic non-mineralized fibrocartilage and mineralized fibrocartilage in tendon-to-bone integration of enthesis. The growth of the in situ apatite nanoparticle layer was induced on the nano hydroxyapatite-poly-l-lactic acid (nHA-PLLA) fibrous layer in simulated body solution, and the poly-l-lactic acid (PLLA) fibrous layer retained its original properties to induce tendon regeneration. The in vivo results showed that BFM significantly increased the area of glycosaminoglycan staining at the tendon-bone interface and improved collagen organization when compared to the simplex fibrous membrane (SFM) of PLLA. Implanting the bipolar membrane also induced bone formation and fibrillogenesis as assessed by micro-CT and histological analysis. Biomechanical testing showed that the BFM group had a greater ultimate load-to-failure and stiffness than the SFM group at 12weeks after surgery. Therefore, this flexible bipolar nanofibrous membrane improves the healing and regeneration process of the enthesis in rotator cuff repair. In this study, we generated a biomimetic dual-layer organic/inorganic flexible bipolar fibrous membrane by sequential electrospinning and in situ biomineralization, producing integrated bipolar fibrous membranes of PLLA fibrous membrane as the upper layer and nHA-PLLA fibrous membrane as the lower layer to mimic non-mineralized fibrocartilage and mineralized fibrocartilage in tendon-to-bone integration of enthesis. Flexible bipolar nanofibrous membranes could be easily fabricated with gradient microstructure for enthesis regeneration in rotator cuff tears. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  15. Advanced Materials for PEM-Based Fuel Cell Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    James E. McGrath; Donald G. Baird; Michael von Spakovsky

    2005-10-26

    Proton exchange membrane fuel cells (PEMFCs) are quickly becoming attractive alternative energy sources for transportation, stationary power, and small electronics due to the increasing cost and environmental hazards of traditional fossil fuels. Two main classes of PEMFCs include hydrogen/air or hydrogen/oxygen fuel cells and direct methanol fuel cells (DMFCs). The current benchmark membrane for both types of PEMFCs is Nafion, a perfluorinated sulfonated copolymer made by DuPont. Nafion copolymers exhibit good thermal and chemical stability, as well as very high proton conductivity under hydrated conditions at temperatures below 80 degrees C. However, application of these membranes is limited due tomore » their high methanol permeability and loss of conductivity at high temperatures and low relative humidities. These deficiencies have led to the search for improved materials for proton exchange membranes. Potential PEMs should have good thermal, hydrolytic, and oxidative stability, high proton conductivity, selective permeability, and mechanical durability over long periods of time. Poly(arylene ether)s, polyimides, polybenzimidazoles, and polyphenylenes are among the most widely investigated candidates for PEMs. Poly(arylene ether)s are a promising class of proton exchange membranes due to their excellent thermal and chemical stability and high glass transition temperatures. High proton conductivity can be achieved through post-sulfonation of poly(arylene ether) materials, but this most often results in very high water sorption or even water solubility. Our research has shown that directly polymerized poly(arylene ether) copolymers show important advantages over traditional post-sulfonated systems and also address the concerns with Nafion membranes. These properties were evaluated and correlated with morphology, structure-property relationships, and states of water in the membranes. Further improvements in properties were achieved through incorporation of inorganic fillers, such as phosphotungstic acid and zirconium hydrogen phosphate. Block copolymers were also studied due to the possibility to achieve a desired combination of homopolymer properties as well as the unique morphologies that are possible with block copolymers. Bezoyl substituted poly(p-phenylene) blocks were combined with poly(arylene ether) blocks to merge the structural rigidity of the poly(p-phenylene) with the ductility and high protonic conductivity of the poly(arylene ether)s. As evidenced by our many refereed publications and preprints, the research that we have conducted over the past several years has made a valuable and significant contribution to the literature and to the state of understanding of proton exchange membranes. Our early efforts at scale-up have suggested that the directly polymerized disulfonated poly(arylene ether sulfone) copolymers are commercially viable alternatives for proton exchange membranes. A new process for bipolar plates was developed and is described. An important single domain PEMFC model was developed and is documented in herein.« less

  16. Organic thermoelectric materials for energy harvesting and temperature control

    NASA Astrophysics Data System (ADS)

    Russ, Boris; Glaudell, Anne; Urban, Jeffrey J.; Chabinyc, Michael L.; Segalman, Rachel A.

    2016-10-01

    Conjugated polymers and related processing techniques have been developed for organic electronic devices ranging from lightweight photovoltaics to flexible displays. These breakthroughs have recently been used to create organic thermoelectric materials, which have potential for wearable heating and cooling devices, and near-room-temperature energy generation. So far, the best thermoelectric materials have been inorganic compounds (such as Bi2Te3) that have relatively low Earth abundance and are fabricated through highly complex vacuum processing routes. Molecular materials and hybrid organic-inorganic materials now demonstrate figures of merit approaching those of these inorganic materials, while also exhibiting unique transport behaviours that are suggestive of optimization pathways and device geometries that were not previously possible. In this Review, we discuss recent breakthroughs for organic materials with high thermoelectric figures of merit and indicate how these materials may be incorporated into new module designs that take advantage of their mechanical and thermoelectric properties.

  17. Exploring the Photovoltaic Performance of All-Inorganic Ag2PbI4/PbI2 Blends.

    PubMed

    Frolova, Lyubov A; Anokhin, Denis V; Piryazev, Alexey A; Luchkin, Sergey Yu; Dremova, Nadezhda N; Troshin, Pavel A

    2017-04-06

    We present an all-inorganic photoactive material composed of Ag 2 PbI 4 and PbI 2 , which shows unexpectedly good photovoltaic performance in planar junction solar cells delivering external quantum efficiencies of ∼60% and light power conversion efficiencies of ∼3.9%. The revealed characteristics are among the best reported to date for metal halides with nonperovskite crystal structure. Most importantly, the obtained results suggest a possibility of reaching high photovoltaic efficiencies for binary and, probably, also ternary blends of different inorganic semiconductor materials. This approach, resembling the bulk heterojunction concept guiding the development of organic photovoltaics for two decades, opens wide opportunities for rational design of novel inorganic and hybrid materials for efficient and sustainable photovoltaic technologies.

  18. Efficient light harvesting within a C153@Zr-based MOF embedded in a polymeric film: spectral and dynamical characterization.

    PubMed

    Gutiérrez, M; López-González, M; Sánchez, F; Douhal, A

    2017-07-21

    Light harvesting is a natural phenomenon that scientists try to mimic in artificial systems. Having this in mind, attention has been focused on using new smart-materials for photonics. Herein, we report on the photobehaviour of a Zr-NDC MOF (NDC = dimethyl 2,6-naphthalenedicarboxylate) and its composite material, Coumarin153@Zr-NDC, embedded within a polymeric membrane of poly[bisphenol A carbonate-co-4,4'-(3,3,5-trimethylcyclohexylidene)diphenol carbonate] (PC). For the mixed matrix membrane (MMM) Zr-NDC/PC, we observed interparticle excimer-like formation, taking place in times shorter than 15 ps and giving rise to a red-shifted broad emission band. The interparticle interactions are supported by the SEM images, as they reflect the contact between the MOF crystals. The C153@Zr-NDC/PC material presents an energy transfer (ET) process from the excited MOF to the trapped C153 molecules in 820 ps, with a 35 nm red-shifted emission band corresponding to C153 in PC. The fluorescence quantum yield, as a result of this ET from the MOF, is high enough (25%) to explore the possibility of using this new composite material in a LED device. To elucidate the observed photobehavior, we compared it with those of C153/PC and (2,6-NDC + C153)/PC films. These results shed light on the spectroscopic and dynamical properties of these new composite materials formed by a highly fluorescent molecule, and easily synthesized MOFs and polymeric matrices, opening the way for more research based on these mixed inorganic and organic compounds for possible applications in the fields of luminescence sensing and emitting devices.

  19. Microscopic origin of entropy-driven polymorphism in hybrid organic-inorganic perovskite materials

    NASA Astrophysics Data System (ADS)

    Butler, Keith T.; Svane, Katrine; Kieslich, Gregor; Cheetham, Anthony K.; Walsh, Aron

    2016-11-01

    Entropy is a critical, but often overlooked, factor in determining the relative stabilities of crystal phases. The importance of entropy is most pronounced in softer materials, where small changes in free energy can drive phase transitions, which has recently been demonstrated in the case of organic-inorganic hybrid-formate perovskites. In this Rapid Communication we demonstrate the interplay between composition and crystal structure that is responsible for the particularly pronounced role of entropy in determining polymorphism in hybrid organic-inorganic materials. Using ab initio based lattice dynamics, we probe the origins and effects of vibrational entropy of four archetype perovskite (A B X3 ) structures. We consider an inorganic material (SrTiO3), an A -site hybrid-halide material (CH3NH3) PbI3 , a X -site hybrid material KSr (BH4)3 , and a mixed A - and X -site hybrid-formate material (N2H5) Zn (HCO2)3 , comparing the differences in entropy between two common polymorphs. The results demonstrate the importance of low-frequency intermolecular modes in determining the phase stability in these materials. The understanding gained allows us to propose a general principle for the relative stability of different polymorphs of hybrid materials as temperature is increased.

  20. Phosphoric acid functionalized pre-sintered meso-silica for high temperature proton exchange membrane fuel cells.

    PubMed

    Zeng, Jie; He, Beibei; Lamb, Krystina; De Marco, Roland; Shen, Pei Kang; Jiang, San Ping

    2013-05-21

    An inorganic proton exchange membrane based on sintered mesoporous silica and phosphoric acid was developed with a high proton conductivity of 0.06 S cm(-1) at 200 °C, achieving an excellent power output of 689 mW cm(-2) in H2 at 190 °C and 200 mW cm(-2) in methanol at 200 °C with no external humidification.

  1. Evaluation of treated sewage reuse potential and membrane-based water reuse technology for the Bangkok Metropolitan area.

    PubMed

    Chiemchaisri, Chart; Chiemchaisri, Wilai; Prasertkulsak, Sirilak; Hamjinda, Nutta Sangnarin; Kootatep, Thammarat; Itonaga, Takanori; Yamamoto, Kazuo

    2015-01-01

    Only 3.4% of total water use in the Bangkok Metropolitan area is reused treated sewage. This study anticipates that further treated-sewage reuse in industrial sectors, commercial buildings and public parks, in addition to present in-plant and street cleaning purposes, would increase total water reuse to about 10%. New water reuse technologies using membrane bioreactor (MBR) and microfiltration (MF) as tertiary treatment were implemented to assess their potential for their application in the Bangkok Metropolitan area. The MBR was applied to the treatment of raw sewage in a central treatment plant of the Bangkok Metropolitan area. The MF membrane was used for polishing the effluent of the treatment plant. The results show the quality of treated water from MBR and tertiary MF treatment could meet stringent water reuse quality standard in terms of biochemical oxygen demand, suspended solids and biological parameters. Constant permeate flux of the membrane was achieved over long-term operation, during which inorganic fouling was observed. This is due to the fact that incoming sewage contains a considerable amount of inorganic constituents contributed from storm water and street inlet in the combined sewerage systems. The total cost of the MBR for sewage treatment and production of reuse water is estimated to be about USD1.10/m3.

  2. Hollow Fiber Space Suit Water Membrane Evaporator Development for Lunar Missions

    NASA Technical Reports Server (NTRS)

    Bue, Grant C.; Trevino, Luis A.; Hanford, Anthony J.; Mitchell, Keith

    2009-01-01

    The Space Suit Water Membrane Evaporator (SWME) is the baseline heat rejection technology selected for development for the Constellation lunar suit. The Hollow Fiber (HoFi) SWME is being considered for service in the Constellation Space Suit Element (CSSE) Portable Life Support Subsystem (PLSS) to provide cooling to the thermal loop through water evaporation to the vacuum of space. Previous work described the test methodology and planning to compare the test performance of three commercially available hollow fiber materials as alternatives to the sheet membrane prototype for SWME: 1) porous hydrophobic polypropylene, 2) porous hydrophobic polysulfone, and 3) ion exchange through nonporous hydrophilic modified Nafion. Contamination tests were performed to probe for sensitivities of the candidate SWME elements to organics and non-volative inorganics expected to be found in the target feedwater source, i.e., potable water provided by the vehicle. The resulting presence of precipitate in the coolant water could plug pores and tube channels and affect the SWME performance. From this prior work, a commercial porous hydrophobic hollow fiber was selected to satisfy both the sensitivity question and the need to provide 800 W of heat rejection. This paper describes the trade studies, the design methodology, and the hollow fiber test data used to design a full

  3. Membrane-less hybrid flow battery based on low-cost elements

    NASA Astrophysics Data System (ADS)

    Leung, P. K.; Martin, T.; Shah, A. A.; Mohamed, M. R.; Anderson, M. A.; Palma, J.

    2017-02-01

    The capital cost of conventional redox flow batteries is relatively high (>USD 200/kWh) due to the use of expensive active materials and ion-exchange membranes. This paper presents a membrane-less hybrid organic-inorganic flow battery based on the low-cost elements zinc (92.7% with the use of carbon felt electrodes. In the presence of a fully oxidized active species close to its solubility limit, dissolution of the deposited anode is relatively slow (<2.37 g h-1 cm-2) with an equivalent corrosion current density of <1.9 mA cm-2. In a parallel plate flow configuration, the resulting battery was charge-discharge cycled at 30 mA cm-2 with average coulombic and energy efficiencies of c.a. 71.8 and c.a. 42.0% over 20 cycles, respectively.

  4. The influence of composition and final pyrolysis temperature variations on global kinetics of combustion of segregated municipal solid waste

    NASA Astrophysics Data System (ADS)

    Pranoto; Himawanto, D. A.; Arifin, N. A.

    2017-04-01

    The combustion of segregated municipal solid waste (MSW) and the resulted char from the pyrolysis process were investigated in this research. The segregated MSW that was collected and used can be divided into organic and inorganic waste materials. The organic materials were bamboo and banana leaves and the inorganic materials were Styrofoam and snack wrappings. The composition ratio of the waste was based on the percentage of weight of each sample. The thermal behaviour of the segregated MSW was investigated by thermo gravimetric analysis. For the pyrolysis process the prepared samples of 200gram were heated from ambient temperature until a variance of final pyrolysis temperature of 550°C, 650°C and 750°C at a constant heating rate of 25°C/min. It was found that the highest activation energy of the raw materials is achieved from sample CC1 (Char with 100% inorganic materials). The activation energy of the raw materials is relatively lower than that of the char. The higher the final pyrolysis temperature, the lower the calorific value of char. The calorific value gradually increases with the amount of inorganic materials.

  5. Hydrogen Purification Using Natural Zeolite Membranes

    NASA Technical Reports Server (NTRS)

    DelValle, William

    2003-01-01

    The School of Science at Universidad del Turabo (UT) have a long-lasting investigation plan to study the hydrogen cleaning and purification technologies. We proposed a research project for the synthesis, phase analysis and porosity characterization of zeolite based ceramic perm-selective membranes for hydrogen cleaning to support NASA's commitment to achieving a broad-based research capability focusing on aerospace-related issues. The present study will focus on technology transfer by utilizing inorganic membranes for production of ultra-clean hydrogen for application in combustion. We tested three different natural zeolite membranes (different particle size at different temperatures and time of exposure). Our results show that the membranes exposured at 900 C for 1Hr has the most higher permeation capacity, indicated that our zeolite membranes has the capacity to permeate hydrogen.

  6. Development and characterization of polyethersulfone/TiO2 mixed matrix membranes for CO2/CH4 separation

    NASA Astrophysics Data System (ADS)

    Galaleldin, S.; Mannan, H. A.; Mukhtar, H.

    2017-12-01

    In this study, mixed matrix membranes comprised of polyethersulfone as the bulk polymer phase and titanium dioxide (TiO2) nanoparticles as the inorganic discontinuous phase were prepared for CO2/CH4 separation. Membranes were synthesized at filler loading of 0, 5, 10 and 15 wt % via dry phase inversion method. Morphology, chemical bonding and thermal characteristics of membranes were scrutinized utilizing different techniques, namely: Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform InfraRed (FTIR) spectra and Thermogravimetric analysis (TGA) respectively. Membranes gas separation performance was evaluated for CO2 and CH4 gases at 4 bar feed pressure. The highest separation performance was achieved by mixed matrix membrane (MMM) at 5 % loading of TiO2.

  7. Geological and Inorganic Materials.

    ERIC Educational Resources Information Center

    Jackson, L. L.; And Others

    1989-01-01

    Presents a review focusing on techniques and their application to the analysis of geological and inorganic materials that offer significant changes to research and routine work. Covers geostandards, spectroscopy, plasmas, microbeam techniques, synchrotron X-ray methods, nuclear activation methods, chromatography, and electroanalytical methods.…

  8. Synthesis of nanostructured materials in inverse miniemulsions and their applications.

    PubMed

    Cao, Zhihai; Ziener, Ulrich

    2013-11-07

    Polymeric nanogels, inorganic nanoparticles, and organic-inorganic hybrid nanoparticles can be prepared via the inverse miniemulsion technique. Hydrophilic functional cargos, such as proteins, DNA, and macromolecular fluoresceins, may be conveniently encapsulated in these nanostructured materials. In this review, the progress of inverse miniemulsions since 2000 is summarized on the basis of the types of reactions carried out in inverse miniemulsions, including conventional free radical polymerization, controlled/living radical polymerization, polycondensation, polyaddition, anionic polymerization, catalytic oxidation reaction, sol-gel process, and precipitation reaction of inorganic precursors. In addition, the applications of the nanostructured materials synthesized in inverse miniemulsions are also reviewed.

  9. Organic-inorganic hybrid mesoporous silicas: functionalization, pore size, and morphology control.

    PubMed

    Park, Sung Soo; Ha, Chang-Sik

    2006-01-01

    Topological design of mesoporous silica materials, pore architecture, pore size, and morphology are currently major issues in areas such as catalytic conversion of bulky molecules, adsorption, host-guest chemistry, etc. In this sense, we discuss the pore size-controlled mesostructure, framework functionalization, and morphology control of organic-inorganic hybrid mesoporous silicas by which we can improve the applicability of mesoporous materials. First, we explain that the sizes of hexagonal- and cubic-type pores in organic-inorganic hybrid mesoporous silicas are well controlled from 24.3 to 98.0 A by the direct micelle-control method using an organosilica precursor and surfactants with different alkyl chain lengths or triblock copolymers as templates and swelling agents incorporated in the formed micelles. Second, we describe that organic-inorganic hybrid mesoporous materials with various functional groups form various external morphologies such as rod, cauliflower, film, rope, spheroid, monolith, and fiber shapes. Third, we discuss that transition metals (Ti and Ru) and rare-earth ions (Eu(3+) and Tb(3+)) are used to modify organic-inorganic hybrid mesoporous silica materials. Such hybrid mesoporous silica materials are expected to be applied as excellent catalysts for organic reactions, photocatalysis, optical devices, etc. c) 2006 The Japan Chemical Journal Forum and Wiley Periodicals, Inc.

  10. Combinatorial synthesis of inorganic or composite materials

    DOEpatents

    Goldwasser, Isy; Ross, Debra A.; Schultz, Peter G.; Xiang, Xiao-Dong; Briceno, Gabriel; Sun, Xian-Dong; Wang, Kai-An

    2010-08-03

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials or, alternatively, allowing the components to interact to form at least two different materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, nonbiological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  11. Novel organic-inorganic hybrid mesoporous materials and nanocomposites

    NASA Astrophysics Data System (ADS)

    Feng, Qiuwei

    Organic-inorganic hybrid mesoporous materials have been prepared successfully via the nonsurfactant templated sol-gel pathway using dibenzoyl-L-tartaric acid (DBTA) as the templating compound. Styrene and methyl methacrylate polymers have been incorporated into the mesoporous silica matrix on the molecular level. The synthetic conditions have been systematically studied and optimized. Titania based mesoporous materials have also been made using nonionic polyethylene glycol surfactant as the pore forming or structure-directing agent. In all of the above mesoporous materials, pore structures have been studied in detail by Transmission Electron Microscopy (TEM), X-ray diffraction and Brunauer-Emmett-Teller (BET) characterizations. The relationship between the template concentration and the pore parameters has been established. This nonsurfactant templated pathway possesses many advantages over the known surfactant approaches such as low cost, environment friendly and biocompatability. To overcome the drawback of nonsurfactant templated mesoporous materials that lack a well ordered pore structure, a flow induced synthesis has been attempted to orientate the sol-gel solution in order to obtain aligned pore structures. The versatility of this nonsurfactant templated pathway can even be extended to the making of organic-inorganic hybrid nanocomposite materials. On the basis of this approach, polymer-silica nanocomposite materials have been prepared using a polymerizable template. It is shown that the organic monomer such as hydroxyethyl methacrylate can act as a template in making nanoporous silica materials and then be further polymerized through a post synthesis technique. The properties and morphology of this new material have been studied by Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM) and Infrared Absorption Spectroscopy (FTIR). Electroactive organic-inorganic hybrid materials have also been synthesized via the sol-gel process. A coupling agent was used to covalently bond the organic and inorganic species. The morphology and conductivity of the products have been investigated.

  12. Effect of pH and polypropylene beads in hybrid water treatment process of alumina ceramic microfiltration and PP beads with air back-flushing and UV irradiation.

    PubMed

    Park, Jin Yong; Song, Seunghwa

    2017-07-07

    For advanced water treatment, effects of pH and pure polypropylene (PP) beads packing concentration on membrane fouling and treatment efficiency were observed in a hybrid process of alumina ceramic microfiltration (MF; pore size 0.1 μm) and pure PP beads. Instead of natural organic matters and fine inorganic particles in natural water source, a quantity of humic acid (HA) and kaolin was dissolved in distilled water. The synthetic feed flowed inside the MF membrane, and the permeated water contacted the PP beads fluidized in the gap of the membrane and the acryl module case with outside UV irradiation. Periodic air back-flushing was performed to control membrane fouling during 10 s per 10 min. The membrane fouling resistance (R f ) was the maximum at 30 g/L of PP bead concentration. Finally, the maximum total permeated volume (V T ) was acquired at 5 g/L of PP beads, because flux maintained higher all through the operation. The treatment efficiency of turbidity was almost constant, independent of PP bead concentration; however, that of dissolved organic materials (DOM) showed the maximal at 50 g/L of PP beads. The R f increased as increasing feed pH from 5 to 9; however, the maximum V T was acquired at pH 6. It means that the membrane fouling could be inhibited at low acid condition. The treatment efficiency of turbidity increased a little, and that of DOM increased from 73.6 to 75.7% as increasing pH from 5 to 9.

  13. A Short Review of Membrane Fouling in Forward Osmosis Processes

    PubMed Central

    Chun, Youngpil; Mulcahy, Dennis; Zou, Linda; Kim, In S.

    2017-01-01

    Interest in forward osmosis (FO) research has rapidly increased in the last decade due to problems of water and energy scarcity. FO processes have been used in many applications, including wastewater reclamation, desalination, energy production, fertigation, and food and pharmaceutical processing. However, the inherent disadvantages of FO, such as lower permeate water flux compared to pressure driven membrane processes, concentration polarisation (CP), reverse salt diffusion, the energy consumption of draw solution recovery and issues of membrane fouling have restricted its industrial applications. This paper focuses on the fouling phenomena of FO processes in different areas, including organic, inorganic and biological categories, for better understanding of this long-standing issue in membrane processes. Furthermore, membrane fouling monitoring and mitigation strategies are reviewed. PMID:28604649

  14. Inorganic Photovoltaics Materials and Devices: Past, Present, and Future

    NASA Technical Reports Server (NTRS)

    Hepp, Aloysius F.; Bailey, Sheila G.; Rafaelle, Ryne P.

    2005-01-01

    This report describes recent aspects of advanced inorganic materials for photovoltaics or solar cell applications. Specific materials examined will be high-efficiency silicon, gallium arsenide and related materials, and thin-film materials, particularly amorphous silicon and (polycrystalline) copper indium selenide. Some of the advanced concepts discussed include multi-junction III-V (and thin-film) devices, utilization of nanotechnology, specifically quantum dots, low-temperature chemical processing, polymer substrates for lightweight and low-cost solar arrays, concentrator cells, and integrated power devices. While many of these technologies will eventually be used for utility and consumer applications, their genesis can be traced back to challenging problems related to power generation for aerospace and defense. Because this overview of inorganic materials is included in a monogram focused on organic photovoltaics, fundamental issues and metrics common to all solar cell devices (and arrays) will be addressed.

  15. Characterization of proton exchange membrane materials for fuel cells by solid state nuclear magnetic resonance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kong, Zueqian

    2010-01-01

    Solid-state nuclear magnetic resonance (NMR) has been used to explore the nanometer-scale structure of Nafion, the widely used fuel cell membrane, and its composites. We have shown that solid-state NMR can characterize chemical structure and composition, domain size and morphology, internuclear distances, molecular dynamics, etc. The newly-developed water channel model of Nafion has been confirmed, and important characteristic length-scales established. Nafion-based organic and inorganic composites with special properties have also been characterized and their structures elucidated. The morphology of Nafion varies with hydration level, and is reflected in the changes in surface-to-volume (S/V) ratio of the polymer obtained by small-anglemore » X-ray scattering (SAXS). The S/V ratios of different Nafion models have been evaluated numerically. It has been found that only the water channel model gives the measured S/V ratios in the normal hydration range of a working fuel cell, while dispersed water molecules and polymer ribbons account for the structures at low and high hydration levels, respectively.« less

  16. The effect of materials selection on metals reduction in propylene glycol methyl ether acetate, PGMEA

    NASA Astrophysics Data System (ADS)

    Entezarian, Majid; Geiger, Bob

    2016-03-01

    The trend in microelectronics fabrication is to produce nano-features measuring down to 10 nm and finer. The PPT levels of organic and inorganic contaminants in the photoresist, solvent and cleaning solutions are becoming a major processing variable affecting the process capability and defectivity. The photoresist usually contains gels, metals, and particulates that could interfere with the lithography process and cause microbridging defects. Nano filters of 5 nm polypropylene, 5 nm polyethylene, and 10 nm natural nylon were used to filter propylene glycol methyl ether acetate PGMEA containing 50 ppb of Na, Mg, Al, Ca, Cr, Mn, Fe, Cu, Zn, and Pb. All filters were effective in removing trivalent Al, Cr, and Fe metals indicating the mechanism for their removal as mechanical sieving. However, the nylon was also very effective in removing the divalent metals showing adsorptive properties. Furthermore, the metal removal of the nylon membrane was studied as a function of surface chemistry. Natural and charged 40 nm nylon membranes were tested and found that charged nylon is more effective for metal removal.

  17. CHEMICAL TRANSPORT FACILITATED BY COLLOIDAL-SIZED ORGANIC MOLECULES

    EPA Science Inventory

    The fluid passing through the pores of soils and geologic materials is not just water with dissolved inorganic chemicals, but a complex mixture of organic and inorganic molecules. Large organic molecules such as humic and fulvic materials may impact the movement of contaminants. ...

  18. Mechanics and thermal management of stretchable inorganic electronics.

    PubMed

    Song, Jizhou; Feng, Xue; Huang, Yonggang

    2016-03-01

    Stretchable electronics enables lots of novel applications ranging from wearable electronics, curvilinear electronics to bio-integrated therapeutic devices that are not possible through conventional electronics that is rigid and flat in nature. One effective strategy to realize stretchable electronics exploits the design of inorganic semiconductor material in a stretchable format on an elastomeric substrate. In this review, we summarize the advances in mechanics and thermal management of stretchable electronics based on inorganic semiconductor materials. The mechanics and thermal models are very helpful in understanding the underlying physics associated with these systems, and they also provide design guidelines for the development of stretchable inorganic electronics.

  19. Mechanics and thermal management of stretchable inorganic electronics

    PubMed Central

    Song, Jizhou; Feng, Xue; Huang, Yonggang

    2016-01-01

    Stretchable electronics enables lots of novel applications ranging from wearable electronics, curvilinear electronics to bio-integrated therapeutic devices that are not possible through conventional electronics that is rigid and flat in nature. One effective strategy to realize stretchable electronics exploits the design of inorganic semiconductor material in a stretchable format on an elastomeric substrate. In this review, we summarize the advances in mechanics and thermal management of stretchable electronics based on inorganic semiconductor materials. The mechanics and thermal models are very helpful in understanding the underlying physics associated with these systems, and they also provide design guidelines for the development of stretchable inorganic electronics. PMID:27547485

  20. Role of organic and inorganic cations on thermal behavior of lead iodide perovskites

    NASA Astrophysics Data System (ADS)

    Singh, Rajan Kumar; Dash, Saumya R.; Kumar, Ranveer; Jain, Neha; Singh, Jai

    2018-04-01

    Recently, organic-inorganic perovskite materials have attracted much attention due to their enormous potential for use in future of new sustainable energy sources. However, fabrication of environmental friendly perovskite and achieving better stability is a major concern towards the commercialization. Here we study the role of cations in the perovskite powder and their influence upon thermodynamic stability. In this study we find, inorganic (cesium, Cs+) cation is shown to be more efficient in the thermal stabilization of the perovskite material than organic (methylamine, CH3NH2+) cation. This study reviles that stability of perovskite can be improved by incorporation of inorganic cation.

  1. Organic materials as templates for the formation of mesoporous inorganic materials and ordered inorganic nanocomposites

    NASA Astrophysics Data System (ADS)

    Ziegler, Christopher R.

    Hierarchically structured inorganic materials are everywhere in nature. From unicellular aquatic algae such as diatoms to the bones and/or cartilage that comprise the skeletal systems of vertebrates. Complex mechanisms involving site-specific chemistries and precision kinetics are responsible for the formation of such structures. In the synthetic realm, reproduction of even the most basic hierarchical structure effortlessly produced in nature is difficult. However, through the utilization of self-assembling structures or "templates", such as polymers or amphiphilic surfactants, combined with some favorable interaction between a chosen inorganic, the potential exists to imprint an inorganic material with a morphology dictated via synthetic molecular self-assembly. In doing so, a very basic hierarchical structure is formed on the angstrom and nanometer scales. The work presented herein utilizes the self-assembly of either surfactants or block copolymers with the desired inorganic or inorganic precursor to form templated inorganic structures. Specifically, mesoporous silica spheres and copolymer directed calcium phosphate-polymer composites were formed through the co-assembly of an organic template and a precursor to form the desired mesostructured inorganic. For the case of the mesoporous silica spheres, a silica precursor was mixed with cetyltrimethylammonium bromide and cysteamine, a highly effective biomimetic catalyst for the conversion of alkoxysilanes to silica. Through charge-based interactions between anionic silica species and the micelle-forming cationic surfactant, ordered silica structures resulted. The incorporation of a novel, effective catalyst was found to form highly condensed silica spheres for potential application as catalyst supports or an encapsulation media. Ordered calcium phosphate-polymer composites were formed using two routes. Both routes take advantage of hydrogen bonding and ionic interactions between the calcium and phosphate precursors and the self-assembling copolymer template. Some evidence suggests that the copolymer morphology remained in the composite despite the known tendency for calcium phosphates to form highly elongated crystalline structures with time, as is commonly the case for synthetic hydroxyapatites. Such materials have obvious application as bone grafts and bone coatings due, in part, to the osteoconductive nature of calcium phosphate as well as to the mesoporosity generated through the cooperative assembly of the block copolymer and the inorganic. Future work, including potential experiments to determine osteoconductivity of as-prepared composites, is also presented herein.

  2. Composition and method to remove asbestos

    DOEpatents

    Block, Jacob

    1998-05-19

    A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed, wherein the composition comprises water, at least about 30% by weight of a boron tetrafluoride salt, free of or having only small amounts of an inorganic acid, an inorganic acid salt or a mixture thereof. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

  3. Composition and method to remove asbestos

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Block, J.

    A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed. The composition comprises water, at least about 30% by weight of a boron tetrafluoride salt, free of or having only small amounts of an inorganic acid, an inorganic acid salt or a mixture thereof. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

  4. Composition and method to remove asbestos

    DOEpatents

    Block, J.

    1998-05-19

    A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed. The composition comprises water, at least about 30% by weight of a hexafluorosilicate salt, and free of or having only small amounts of an inorganic acid, an inorganic acid salt or a mixture thereof. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

  5. Composition and method to remove asbestos

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Block, J.

    A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed. The composition comprises water, at least about 30% by weight of a hexafluorosilicate salt, and free of or having only small amounts of an inorganic acid, an inorganic acid salt or a mixture thereof. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

  6. Composition and method to remove asbestos

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Block, Jacob

    A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed, wherein the composition comprises water, at least about 30% by weight of a hexafluorosilicate salt, and free of or having only small amounts of an inorganic acid, an inorganic acid salt or a mixture thereof. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

  7. Composition and method to remove asbestos

    DOEpatents

    Block, J.

    1998-05-19

    A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed. The composition comprises water, at least about 30% by weight of a boron tetrafluoride salt, free of or having only small amounts of an inorganic acid, an inorganic acid salt or a mixture thereof. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

  8. Perspective: Toward "synthesis by design": Exploring atomic correlations during inorganic materials synthesis

    NASA Astrophysics Data System (ADS)

    Soderholm, L.; Mitchell, J. F.

    2016-05-01

    Synthesis of inorganic extended solids is a critical starting point from which real-world functional materials and their consequent technologies originate. However, unlike the rich mechanistic foundation of organic synthesis, with its underlying rules of assembly (e.g., functional groups and their reactivities), the synthesis of inorganic materials lacks an underpinning of such robust organizing principles. In the latter case, any such rules must account for the diversity of chemical species and bonding motifs inherent to inorganic materials and the potential impact of mass transport on kinetics, among other considerations. Without such assembly rules, there is less understanding, less predictive power, and ultimately less control of properties. Despite such hurdles, developing a mechanistic understanding for synthesis of inorganic extended solids would dramatically impact the range of new material discoveries and resulting new functionalities, warranting a broad call to explore what is possible. Here we discuss our recent approaches toward a mechanistic framework for the synthesis of bulk inorganic extended solids, in which either embryonic atomic correlations or fully developed phases in solutions or melts can be identified and tracked during product selection and crystallization. The approach hinges on the application of high-energy x-rays, with their penetrating power and large Q-range, to explore reaction pathways in situ. We illustrate this process using two examples: directed assembly of Zr clusters in aqueous solution and total phase awareness during crystallization from K-Cu-S melts. These examples provide a glimpse of what we see as a larger vision, in which large scale simulations, data-driven science, and in situ studies of atomic correlations combine to accelerate materials discovery and synthesis, based on the assembly of well-defined, prenucleated atomic correlations.

  9. Perspective: Toward “synthesis by design”: Exploring atomic correlations during inorganic materials synthesis

    DOE PAGES

    Soderholm, L.; Mitchell, J. F.

    2016-05-26

    Synthesis of inorganic extended solids is a critical starting point from which real-world functional materials and their consequent technologies originate. However, unlike the rich mechanistic foundation of organic synthesis, with its underlying rules of assembly (e.g., functional groups and their reactivities), the synthesis of inorganic materials lacks an underpinning of such robust organizing principles. In the latter case, any such rules must account for the diversity of chemical species and bonding motifs inherent to inorganic materials and the potential impact of mass transport on kinetics, among other considerations. Without such assembly rules, there is less understanding, less predictive power, andmore » ultimately less control of properties. Despite such hurdles, developing a mechanistic understanding for synthesis of inorganic extended solids would dramatically impact the range of new material discoveries and resulting new functionalities, warranting a broad call to explore what is possible. Here we discuss our recent approaches toward a mechanistic framework for the synthesis of bulk inorganic extended solids, in which either embryonic atomic correlations or fully developed phases in solutions or melts can be identified and tracked during product selection and crystallization. The approach hinges on the application of high-energy x-rays, with their penetrating power and large Q-range, to explore reaction pathways in situ. We illustrate this process using two examples: directed assembly of Zr clusters in aqueous solution and total phase awareness during crystallization from K–Cu–S melts. These examples provide a glimpse of what we see as a larger vision, in which large scale simulations, data-driven science, and in situ studies of atomic correlations combine to accelerate materials discovery and synthesis, based on the assembly of well-defined, prenucleated atomic correlations.« less

  10. Composite separators and redox flow batteries based on porous separators

    DOEpatents

    Li, Bin; Wei, Xiaoliang; Luo, Qingtao; Nie, Zimin; Wang, Wei; Sprenkle, Vincent L.

    2016-01-12

    Composite separators having a porous structure and including acid-stable, hydrophilic, inorganic particles enmeshed in a substantially fully fluorinated polyolefin matrix can be utilized in a number of applications. The inorganic particles can provide hydrophilic characteristics. The pores of the separator result in good selectivity and electrical conductivity. The fluorinated polymeric backbone can result in high chemical stability. Accordingly, one application of the composite separators is in redox flow batteries as low cost membranes. In such applications, the composite separator can also enable additional property-enhancing features compared to ion-exchange membranes. For example, simple capacity control can be achieved through hydraulic pressure by balancing the volumes of electrolyte on each side of the separator. While a porous separator can also allow for volume and pressure regulation, in RFBs that utilize corrosive and/or oxidizing compounds, the composite separators described herein are preferable for their robustness in the presence of such compounds.

  11. IRIS Toxicological Review for Inorganic Arsenic (Scoping and Problem Formulation Materials)

    EPA Science Inventory

    In November 2012, EPA released scoping and problem formulation materials for the IRIS assessment of inorganic arsenic for public comment and discussion. The scoping information was based on input from EPA's program and regional offices and was provided for informational purposes....

  12. Self-organization of a tetrasubstituted tetrathiafulvalene (TTF) in a silica based hybrid organic-inorganic material.

    PubMed

    Cerveau, Geneviève; Corriu, Robert J P; Lerouge, Frédéric; Bellec, Nathalie; Lorcy, Dominique; Nobili, Maurizio

    2004-02-21

    A hybrid organic inorganic nanostructured material containing a TTF core substituted by four arms exhibited a high level of both condensation at silicon (96%) and self-organization as evidenced by X-ray diffraction and an unprecedented birefringent behaviour.

  13. Photochromic Inorganic/Organic Thermoplastic Elastomers.

    PubMed

    Zhang, Jiuyang; Li, Jing; Huo, Mengmeng; Li, Naixu; Zhou, Jiancheng; Li, Tuoqi; Jiang, Jing

    2017-08-01

    Photochromic materials are an important class of "smart materials" and are broadly utilized in technological devices. However, most photochromic materials reported so far are composed of inorganic compounds that are challenging to process and suffer from poor mechanical performance, severely limiting their applications in various markets. In this paper, inorganic photochromic tungsten trioxide (WO 3 ) nanocrystals are conveniently grafted with polymers to hurdle the deficiency in processability and mechanical properties. This new type of photochromic material can be thermally processed into desired geometries like disks and dog-bone specimens. Fully reversible photochromic response under UV light is also achieved for WO 3 -graft polymers, exhibiting tunable response rate, outperforming the pristine WO 3 nanocrystals. Notably, the resulted graft polymers show extraordinary mechanical performance with excellent ductility (≈800% breaking strain) and relatively high breaking strength (≈2 MPa). These discoveries elucidate an effective pathway to design smart inorganic/organic hybrid thermoplastic elastomers endowed with outstanding photochromic and mechanical properties as well as exceptional processability. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Characterization and calibration of a viscoelastic simplified potential energy clock model for inorganic glasses

    DOE PAGES

    Chambers, Robert S.; Tandon, Rajan; Stavig, Mark E.

    2015-07-07

    In this study, to analyze the stresses and strains generated during the solidification of glass-forming materials, stress and volume relaxation must be predicted accurately. Although the modeling attributes required to depict physical aging in organic glassy thermosets strongly resemble the structural relaxation in inorganic glasses, the historical modeling approaches have been distinctly different. To determine whether a common constitutive framework can be applied to both classes of materials, the nonlinear viscoelastic simplified potential energy clock (SPEC) model, developed originally for glassy thermosets, was calibrated for the Schott 8061 inorganic glass and used to analyze a number of tests. A practicalmore » methodology for material characterization and model calibration is discussed, and the structural relaxation mechanism is interpreted in the context of SPEC model constitutive equations. SPEC predictions compared to inorganic glass data collected from thermal strain measurements and creep tests demonstrate the ability to achieve engineering accuracy and make the SPEC model feasible for engineering applications involving a much broader class of glassy materials.« less

  15. Process for removing sulfur from coal

    DOEpatents

    Aida, Tetsuo; Squires, Thomas G.; Venier, Clifford G.

    1985-02-05

    A process for the removal of divalent organic and inorganic sulfur compounds from coal and other carbonaceous material. A slurry of pulverized carbonaceous material is contacted with an electrophilic oxidant which selectively oxidizes the divalent organic and inorganic compounds to trivalent and tetravalent compounds. The carbonaceous material is then contacted with a molten caustic which dissolves the oxidized sulfur compounds away from the hydrocarbon matrix.

  16. Method of synthesis of proton conducting materials

    DOEpatents

    Garzon, Fernando Henry; Einsla, Melinda Lou; Mukundan, Rangachary

    2010-06-15

    A method of producing a proton conducting material, comprising adding a pyrophosphate salt to a solvent to produce a dissolved pyrophosphate salt; adding an inorganic acid salt to a solvent to produce a dissolved inorganic acid salt; adding the dissolved inorganic acid salt to the dissolved pyrophosphate salt to produce a mixture; substantially evaporating the solvent from the mixture to produce a precipitate; and calcining the precipitate at a temperature of from about 400.degree. C. to about 1200.degree. C.

  17. Inorganic-organic separators for alkaline batteries

    NASA Technical Reports Server (NTRS)

    Sheibley, D. W. (Inventor)

    1978-01-01

    A flexible separator is reported for use between the electrodes of Ni-Cd and Ni-Zn batteries using alkaline electrolytes. The separator was made by coating a porous substrate with a battery separator composition. The coating material included a rubber-based resin copolymer, a plasticizer and inorganic and organic fillers which comprised 55% by volume or less of the coating as finally dried. One or more of the filler materials, whether organic or inorganic, is preferably active with the alkaline electrolyte to produce pores in the separator coating. The plasticizer was an organic material which is hydrolyzed by the alkaline electrolyte to improve conductivity of the separator coating.

  18. Rotating Reverse Osmosis for Wastewater Reuse

    NASA Technical Reports Server (NTRS)

    Lueptow, Richard M.; Yoon, Yeomin; Pederson, Cynthia

    2004-01-01

    Membrane filtration such as Reverse Osmosis (RO) removes ions, proteins, and organic chemicals which are generally very difficult to remove using conventional treatment. Moreover, membrane is an absolute filtration method, so its treatment efficiency and performance are stable and predictable. We are currently working on the development of rotating RO membrane system. Dynamic rotating membrane filtration, which can produce a high shear rate, may be helpful to obtain high rejection of organic pollutants.The goal of our current work is to improve the flux of the device by increasing pressure by a factor of 3 to 4. In addition, the rejections for a wider variety of inorganic and organic compounds typically found in space mission wastewater are measured.

  19. Solution Based Functionalization of Nanostructured Oxides with Organic Molecules

    NASA Astrophysics Data System (ADS)

    Pearce, Brady Lawrence

    The surface modification of wide bandgap semiconductors with organic molecules provides novel functionalities to the composite material. These functionalities can include tuning of the optical properties, providing solution stability of the inorganic material, as well as many others. The use of an in-situ functionalization method for surface attachment of phosphonic group containing molecules to the surface of gallium nitride (GaN) has shown promise. This technique is particularly advantageous due to the etching and functionalization steps occurring at the same time, in the same beaker, as well as not being reliant on organic solvents or high temperatures. In this functionalization process, surface hydroxide groups are preferentially grown on the surface of GaN, which serve as attachment sites for phosphonic groups on organic moieties. Molecules with these hydroxyl groups available natively on their surface, such as AlOOH and GaOOH, provide a unique advantage. The requirement for an etching step is removed, and the functionalization process could be performed in a simple one-step modification. The work in this dissertation seeks to address the possibility of using these materials as the inorganic component in organic/inorganic composite material in devices. Of particular importance in solar cell and bioelectronic devices is the ability to withstand varying pH environments, and to avoid the leaching of toxic ionic species. Lysine has shown to reduce the leaching of ionic species, when particles of inorganic molecules are cross-linking agents for the amino acid. In this work, the aqueous stability of both AlOOH and GaOOH in a lysine environment will be explored. The optical and size characteristics observed in nanostructured forms of the mixed composition AlxGa1-xOOH material system is of interest, due optical tunability providing a distinct advantage in optoelectronic devices containing these organic/inorganic hybrids. Immobilizing phosphonic group containing organic dyes on the surface of GaN, GaOOH, AlOOH and mixed compositions of AlGaOOH using surface bonding sites, and possible covalent attachments mechanisms, seeks to provide an improvement in the long term stability of the inorganic/organic interface for devices. Future work in this area will test device efficiency using these hybrids, explore additional mixed oxyhydroxide composition systems and continue the advancement of the understanding of the important role of phosphonic groups in organic/inorganic devices. The nature of chemical and surface species in these materials will be characterized with Fourier Transformed-Infrared Spectroscopy (FT-IR) and X-Ray Photoelectric Spectroscopy (XPS). The optical properties of the materials were tested with photoluminescence (PL) spectroscopy, and the stability was examined with fluorescence spectroscopy. The crystallographic nature of the nanostructured inorganic materials before and after functionalization was determined with X-Ray Diffraction (XRD). Images of the nanostructures were obtained with mainly Scanning Electron Microscopy (SEM) as well as Transmission Electron Microscopy (TEM). The work in this dissertation seeks to address the improvement of the development of nanostructured inorganic/organic hybrid materials, the investigation of novel composites for these applications and the improvement of the long term stability in aqueous medium as well as of the organic/inorganic interface itself.

  20. Novel Inorganic/Polymer Composite Membranes for CO 2 Capture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ho, W.S. Winston; Dutta, Prabir K.; Schmit, Steve J.

    The objective of this project is to develop a cost-effective design and manufacturing process for new membrane modules that capture CO 2 from flue gas in coal-fired power plants. The membrane consisted of a thin selective layer including inorganic (zeolite) embedded in a polymer structure so that it can be made in a continuous manufacturing process. The membrane was incorporated in spiral-wound modules for the field test with actual flue gas at the National Carbon Capture Center (NCCC) in Wilsonville, AL and bench scale tests with simulated flue gas at the Ohio State University (OSU). Using the modules for post-combustionmore » CO 2 capture is expected to achieve the DOE target of $40/tonne CO 2 captured (in 2007 dollar) for 2025. Membranes with the amine-containing polymer cover layer on zeolite-Y (ZY) nanoparticles deposited on the polyethersulfone (PES) substrate were successfully synthesized. The membranes showed a high CO 2 permeance of about 1100 GPU (gas permeation unit, 1 GPU = 10 -6 cm 3 (STP)/(cm 2 • s • cm Hg), 3000 GPU = 10-6 mol/(m 2 • s • Pa)) with a high CO 2/N 2 selectivity of > 200 at the typical flue gas conditions at 57°C (about 17% water vapor in feed gas) and > 1400 GPU CO 2 permeance with > 500 CO 2/N 2 selectivity at 102°C (~ 80% water vapor). The synthesis of ZY nanoparticles was successfully scaled up, and the pilot-scale membranes were also successfully fabricated using the continuous membrane machine at OSU. The transport performance of the pilot-scale membranes agreed reasonably well with the lab-scale membranes. The results from both the lab-scale and scale-up membranes were used for the techno-economic analysis. The scale-up membranes were fabricated into prototype spiral-wound membrane modules for continuous testing with simulated or real flue gas. For real flue gas testing, we worked with NCCC, in consultation with TriSep Corporation, Gradient Technology and American Electric Power (AEP). The membrane module demonstrated > 800 GPU of CO 2 permeance and > 150 CO 2/N 2 selectivity when tested with real flue gas at NCCC. The results obtained were used to update the techno-economic analysis. In addition, the EH&S assessment of the membranes for post-combustion CO 2 capture was conducted.« less

  1. Lipid Nanotechnology

    PubMed Central

    Mashaghi, Samaneh; Jadidi, Tayebeh; Koenderink, Gijsje; Mashaghi, Alireza

    2013-01-01

    Nanotechnology is a multidisciplinary field that covers a vast and diverse array of devices and machines derived from engineering, physics, materials science, chemistry and biology. These devices have found applications in biomedical sciences, such as targeted drug delivery, bio-imaging, sensing and diagnosis of pathologies at early stages. In these applications, nano-devices typically interface with the plasma membrane of cells. On the other hand, naturally occurring nanostructures in biology have been a source of inspiration for new nanotechnological designs and hybrid nanostructures made of biological and non-biological, organic and inorganic building blocks. Lipids, with their amphiphilicity, diversity of head and tail chemistry, and antifouling properties that block nonspecific binding to lipid-coated surfaces, provide a powerful toolbox for nanotechnology. This review discusses the progress in the emerging field of lipid nanotechnology. PMID:23429269

  2. Nanoparticles Formed Onto/Into Halloysite Clay Tubules: Architectural Synthesis and Applications.

    PubMed

    Vinokurov, Vladimir A; Stavitskaya, Anna V; Glotov, Aleksandr P; Novikov, Andrei A; Zolotukhina, Anna V; Kotelev, Mikhail S; Gushchin, Pawel A; Ivanov, Evgenii V; Darrat, Yusuf; Lvov, Yuri M

    2018-01-04

    Nanoparticles, being objects with high surface area are prone to agglomeration. Immobilization onto solid supports is a promising method to increase their stability and it allows for scalable industrial applications, such as metal nanoparticles adsorbed to mesoporous ceramic carriers. Tubular nanoclay - halloysite - can be an efficient solid support, enabling the fast and practical architectural (inside / outside) synthesis of stable metal nanoparticles. The obtained halloysite-nanoparticle composites can be employed as advanced catalysts, ion-conducting membrane modifiers, inorganic pigments, and optical markers for biomedical studies. Here, we discuss the possibilities to synthesize halloysite decorated with metal, metal chalcogenide, and carbon nanoparticles, and to use these materials in various fields, especially in catalysis and petroleum refinery. © 2018 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Rigidified pneumatic composites

    NASA Astrophysics Data System (ADS)

    van Dessel, Steven

    2000-10-01

    The overall objective of the research presented in this dissertation was to address global issues of adequate housing for all and the need for more sustainable human settlement. In order to address these, the emerging technology of rigidified pneumatic composites was investigated. Rigidified pneumatic composites (RPC) are defined as thin flexible membrane structures that are pneumatically deployed. After deployment, these structures harden due to chemical or physical change of the membrane. Because of this change, these structures do no longer require pneumatic pressure to maintain their shape. For the first time, a systematic listing of the various means available to develop polymeric materials useful in RPC technology is presented. With the aim to reduce the cost of RPC structures, a new material was proposed, developed, and evaluated. This material involved the formation of a semi-interpenetrating polymer network based on poly vinyl chloride and an acrylate based reactive plasticizer. The economical and environmental performances of RPC structures using this new material were assessed by means of a case study. In this study, the performance of RPC technology was compared with that of a typical wood light frame structure in the application of a small single-family house. The study indicated that the cost of ownership in present day value for the RPC structure was approximately 33% less than the cost of a comparable wood light frame structure. The study also indicated that significant environmental benefits exist with the use of RPC structures. It was found that the RPC structure used significantly less resources compared to the wood light frame structure. About 3.5 times less materials coming from non-renewable fossil resources, about 2.5 times less materials coming from trees, and about 19 times less materials coming from inorganic resources was used in the RPC structure relative to the wood light frame structure. The study concluded with pointing out various means available to further increase the economical and environmental performance of RPC technology. Directions were provided to guide future developments of RPC technology.

  4. An Investigation of Low Biofouling Copper-charged Membranes

    NASA Astrophysics Data System (ADS)

    Asapu, Sunitha

    Water is essential for the survival of life on Earth, but pollutants in water can cause dangerous diseases and fatalities. The need for purified water has been increasing with increasing world population; however, natural sources of water such as rivers, lakes and streams, are progressively falling shorter and shorter of meeting water needs. The provision of clean, drinkable water to people is a key factor for the development of novel and alternative water purification technologies, such as membrane separations. Nanofiltration (NF) is a membrane separations technology that purifies water from lower quality sources, such as brackish water, seawater and wastewater. During the filtration of such sources, materials that are rejected by the membrane may accumulate on the surface of the membrane to foul it. Such materials include organic and inorganic matter, colloids, salts and microorganisms. The former four can often be controlled via pretreatment; however, the accumulation of microorganisms is more problematic to membranes. Biofouling is the accumulation and growth of microorganisms on the surface of membranes and on feed spacers. After attachment, microorganisms excrete extracellular polymeric substances (EPS), which form a matrix around the organism's outer surface as biofilm. These biofilms are detrimental and result in irreversible membrane fouling. Copper and silver ions inactivate the bacterial cells and prevent the DNA replication in microbial cells. Previous studies using copper-charged feed spacers have shown the ability of copper to control biofouling without a significant amount of copper leaching from copper-charged polypropylene (PP) feed spacers during crossflow filtration. Also, filtration using unmodified speed facers experienced almost 70% flux decline, while filtration using copper-charged feed spacers displayed only 25% flux decline. These intriguing results led to the hypothesis that the polymer chemistry could be extrapolated to produce membranes with increased biofouling resistance. The goal of this project was to develop low-biofouling nanofiltration cellulose acetate (CA) membranes through functionalization with metal chelating ligands charged with biocidal metal ions, i.e. copper ions. To this end, glycidyl methacrylate (GMA), an epoxy, was used to attach a chelating agent, iminodiacetic acid (IDA) to facilitate the charging of copper to the membrane surface. Both CA and CA-GMA membranes were cast using the phase-inversion method. The CA-GMA membranes were then charged with copper ions to make them low biofouling. Pore size distribution analysis of CA and copper charged membranes were conducted using various molecular weights of polyethylene glycol (PEG). CA and copper-charged membranes were characterized using Fourier Transform Infrared (FTIR), contact angle to measure hydrophilicity changes, and using scanning electron microscope (SEM) coupled with X-ray energy dispersive spectroscopy EDS to monitor copper leaching. Permeation experiments were conducted with distilled (DI) water, protein solutions, and synthetic brackish water containing microorganisms. The DI water permeation of the copper-charged membranes was initially lower than the CA membranes. The membranes were then subjected to bovine serum albumin (BSA) and lipase filtration. The copper-charged membranes showed higher pure water flux values for both proteins as compared to CA membranes. The rejection of BSA and lipase was the same for both the copper charged and CA membranes. The filtration with the synthetic brackish water showed that copper-charged membranes had higher flux values as compared to CA membranes, and biofouling analysis showed more bacteria on the CA membranes as compared to copper-charged membranes. Therefore, the copper-charged membranes made here have shown a potential to be used as low-biofouling membranes in the future.

  5. Organic templates for the generation of inorganic materials.

    PubMed

    van Bommel, Kjeld J C; Friggeri, Arianna; Shinkai, Seiji

    2003-03-03

    Mankind's fascination with shapes and patterns, many examples of which come from nature, has greatly influenced areas such as art and architecture. Science too has long since been interested in the origin of shapes and structures found in nature. Whereas organic chemistry in general, and supramolecular chemistry especially, has been very successful in creating large superstructures of often stunning morphology, inorganic chemistry has lagged behind. Over the last decade, however, researchers in various fields of chemistry have been studying novel methods through which the shape of inorganic materials can be controlled at the micro- or even nanoscopic level. A method that has proven very successful is the formation of inorganic structures under the influence of (bio)organic templates, which has resulted in the generation of a large variety of structured inorganic structures that are currently unattainable through any other method.

  6. HIGH FLUX NANOFILTRATION MEMBRANE FOR EMERGING CONTAMINANT CONTROL - PHASE I

    EPA Science Inventory

    A variety of inorganic and organic contaminants originating from municipal, agricultural and industrial wastewater sources are being found with increasing frequency in the Nation’s natural and drinking water supplies. These “emerging contaminants” include ...

  7. Proton conductive montmorillonite-Nafion composite membranes for direct ethanol fuel cells

    NASA Astrophysics Data System (ADS)

    Wu, Xiu-Wen; Wu, Nan; Shi, Chun-Qing; Zheng, Zhi-Yuan; Qi, Hong-Bin; Wang, Ya-Fang

    2016-12-01

    The preparation of Nafion membranes modified with montmorillonites is less studied, and most relative works mainly applied in direct methanol fuel cells, less in direct ethanol fuel cells. Organic/inorganic composite membranes are prepared with different montmorillonites (Ca-montmorillonite, Na-montmorillonite, K-montmorillonite, Mg-montmorillonite, and H-montmorillonite) and Nafion solution via casting method at 293 K in air, and with balance of their proton conductivity and ethanol permeability. The ethanol permeability and proton conductivity of the membranes are comparatively studied. The montmorillonites can well decrease the ethanol permeability of the membranes via inserted them in the membranes, while less decrease the proton conductivities of the membranes depending on the inserted amount and type of montmorillonites. The proton conductivities of the membranes are between 36.0 mS/cm and 38.5 mS/cm. The ethanol permeability of the membranes is between 0.69 × 10-6 cm2/s and 2.67 × 10-6 cm2/s.

  8. Chitosan bio-based organic-inorganic hybrid aerogel microspheres.

    PubMed

    El Kadib, Abdelkrim; Bousmina, Mosto

    2012-07-02

    Recently, organic-inorganic hybrid materials have attracted tremendous attention thanks to their outstanding properties, their efficiency, versatility and their promising applications in a broad range of areas at the interface of chemistry and biology. This article deals with a new family of surface-reactive organic-inorganic hybrid materials built from chitosan microspheres. The gelation of chitosan (a renewable amino carbohydrate obtained by deacetylation of chitin) by pH inversion affords highly dispersed fibrillar networks shaped as self-standing microspheres. Nanocasting of sol-gel processable monomeric alkoxides inside these natural hydrocolloids and their subsequent CO(2) supercritical drying provide high-surface-area organic-inorganic hybrid materials. Examples including chitosan-SiO(2), chitosan-TiO(2), chitosan-redox-clusters and chitosan-clay-aerogel microspheres are described and discussed on the basis of their textural and structural properties, thermal and chemical stability and their performance in catalysis and adsorption. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Mechanical Designs for Inorganic Stretchable Circuits in Soft Electronics.

    PubMed

    Wang, Shuodao; Huang, Yonggang; Rogers, John A

    2015-09-01

    Mechanical concepts and designs in inorganic circuits for different levels of stretchability are reviewed in this paper, through discussions of the underlying mechanics and material theories, fabrication procedures for the constituent microscale/nanoscale devices, and experimental characterization. All of the designs reported here adopt heterogeneous structures of rigid and brittle inorganic materials on soft and elastic elastomeric substrates, with mechanical design layouts that isolate large deformations to the elastomer, thereby avoiding potentially destructive plastic strains in the brittle materials. The overall stiffnesses of the electronics, their stretchability, and curvilinear shapes can be designed to match the mechanical properties of biological tissues. The result is a class of soft stretchable electronic systems that are compatible with traditional high-performance inorganic semiconductor technologies. These systems afford promising options for applications in portable biomedical and health-monitoring devices. Mechanics theories and modeling play a key role in understanding the underlining physics and optimization of these systems.

  10. Mechanical Designs for Inorganic Stretchable Circuits in Soft Electronics

    PubMed Central

    Wang, Shuodao; Huang, Yonggang; Rogers, John A.

    2016-01-01

    Mechanical concepts and designs in inorganic circuits for different levels of stretchability are reviewed in this paper, through discussions of the underlying mechanics and material theories, fabrication procedures for the constituent microscale/nanoscale devices, and experimental characterization. All of the designs reported here adopt heterogeneous structures of rigid and brittle inorganic materials on soft and elastic elastomeric substrates, with mechanical design layouts that isolate large deformations to the elastomer, thereby avoiding potentially destructive plastic strains in the brittle materials. The overall stiffnesses of the electronics, their stretchability, and curvilinear shapes can be designed to match the mechanical properties of biological tissues. The result is a class of soft stretchable electronic systems that are compatible with traditional high-performance inorganic semiconductor technologies. These systems afford promising options for applications in portable biomedical and health-monitoring devices. Mechanics theories and modeling play a key role in understanding the underlining physics and optimization of these systems. PMID:27668126

  11. Electrochemical growth of highly oriented organic-inorganic superlattices using solid-supported multilamellar membranes as templates.

    PubMed

    Xing, Li-Li; Li, Da-Peng; Hu, Shu-Xin; Jing, Huai-Yu; Fu, Honglan; Mai, Zhen-Hong; Li, Ming

    2006-02-08

    Controllable depositing of relatively thick inorganic sublayers into organic templates to fabricate organic-inorganic superlattices is of great importance. We report a novel approach to fabricating phospholipid/Ni(OH)(2) superlattices by electrochemical deposition of the inorganic component into solid-supported multilamellar templates. The well-ordered and highly oriented multilamellar templates are produced by spreading small drops of lipid solution on silicon surfaces and letting the solvent evaporate slowly. The templates which are used as working electrodes preserve the lamellar structure in the electrolyte solution. The resulting superlattices are highly oriented. The thickness of the nickel hydroxide is controlled by the concentration of nickel ions in the electrolyte bath. The electron density profiles derived from the X-ray diffraction data reveal that the thickness of the nickel hydroxide sublayers increases from 15 to 27 A as the concentration of nickel nitrate increases from 0.005 mol/L to 0.08 mol/L. We expect that the new method can be extended to depositing a variety of inorganic components including metals, oxides, and semiconductors.

  12. Berkeley Lab - Materials Sciences Division

    Science.gov Websites

    Chemical and Mechanical Properties of Surfaces, Interfaces and Nanostructures Inorganic-Organic (2016). top Inorganic-Organic Nanocomposites Program Leader: Ting Xu Co-PI's: A. Paul Alivisatos, Yi Liu , Miquel Salmeron, Lin-Wang Wang The organic/inorganic nanocomposite program aims to design and synthesize

  13. Computational evidence for stable inorganic fullerene-like structures of ceramic and semiconductor materials

    NASA Astrophysics Data System (ADS)

    Chang, Ch; Patzer, A. B. C.; Sedlmayr, E.; Steinke, T.; Sülzle, D.

    2001-12-01

    Theoretical electronic structure techniques have become an indispensible and powerful means for predicting molecular properties and designing new materials. Based on a density functional approach and guided by geometric considerations we provide evidence for some specific inorganic fullerene-like cage molecules of ceramic and semiconductor materials which exhibit high energetic stability and point group symmetry as well as nearly perfect spherical shape.

  14. Process for removing sulfur from coal

    DOEpatents

    Aida, T.; Squires, T.G.; Venier, C.G.

    1983-08-11

    A process is disclosed for the removal of divalent organic and inorganic sulfur compounds from coal and other carbonaceous material. A slurry of pulverized carbonaceous material is contacted with an electrophilic oxidant which selectively oxidizes the divalent organic and inorganic compounds to trivalent and tetravalent compounds. The carbonaceous material is then contacted with a molten caustic which dissolves the oxidized sulfur compounds away from the hydrocarbon matrix.

  15. Inorganic nanostructured materials for high performance electrochemical supercapacitors

    NASA Astrophysics Data System (ADS)

    Liu, Sheng; Sun, Shouheng; You, Xiao-Zeng

    2014-01-01

    Electrochemical supercapacitors (ES) are a well-known energy storage system that has high power density, long life-cycle and fast charge-discharge kinetics. Nanostructured materials are a new generation of electrode materials with large surface area and short transport/diffusion path for ions and electrons to achieve high specific capacitance in ES. This mini review highlights recent developments of inorganic nanostructure materials, including carbon nanomaterials, metal oxide nanoparticles, and metal oxide nanowires/nanotubes, for high performance ES applications.

  16. Inorganic nanostructured materials for high performance electrochemical supercapacitors.

    PubMed

    Liu, Sheng; Sun, Shouheng; You, Xiao-Zeng

    2014-02-21

    Electrochemical supercapacitors (ES) are a well-known energy storage system that has high power density, long life-cycle and fast charge-discharge kinetics. Nanostructured materials are a new generation of electrode materials with large surface area and short transport/diffusion path for ions and electrons to achieve high specific capacitance in ES. This mini review highlights recent developments of inorganic nanostructure materials, including carbon nanomaterials, metal oxide nanoparticles, and metal oxide nanowires/nanotubes, for high performance ES applications.

  17. From molecular chemistry to hybrid nanomaterials. Design and functionalization.

    PubMed

    Mehdi, Ahmad; Reye, Catherine; Corriu, Robert

    2011-02-01

    This tutorial review reports upon the organisation and functionalization of two families of hybrid organic-inorganic materials. We attempted to show in both cases the best ways permitting the organisation of materials in terms of properties at the nanometric scale. The first family concerns mesoporous hybrid organic-inorganic materials prepared in the presence of a structure-directing agent. We describe the functionalization of the channel pores of ordered mesoporous silica, that of the silica framework, as well as the functionalization of both of them simultaneously. This family is currently one of the best supports for exploring polyfunctional materials, which can provide a route to interactive materials. The second family concerns lamellar hybrid organic-inorganic materials which is a new class of nanostructured materials. These materials were first obtained by self-assembly, as a result of van der Waals interactions of bridged organosilica precursors containing long alkylene chains during the sol-gel process, without any structure directing agent. This methodology has been extended to functional materials. It is also shown that such materials can be obtained from monosilylated precursors.

  18. Liquid–liquid phase separation in particles containing secondary organic material free of inorganic salts

    DOE PAGES

    Song, Mijung; Liu, Pengfei; Martin, Scot T.; ...

    2017-09-25

    Particles containing secondary organic material (SOM) are ubiquitous in the atmosphere and play a role in climate and air quality. Recently, research has shown that liquid–liquid phase separation (LLPS) occurs at high relative humidity (RH) (greater than ~95 %) in α-pinene-derived SOM particles free of inorganic salts, while LLPS does not occur in isoprene-derived SOM particles free of inorganic salts. We expand on these findings by investigating LLPS at 290 ± 1 K in SOM particles free of inorganic salts produced from ozonolysis of β-caryophyllene, ozonolysis of limonene, and photo-oxidation of toluene. LLPS was observed at greater than ~95 %more » RH in the biogenic SOM particles derived from β-caryophyllene and limonene while LLPS was not observed in the anthropogenic SOM particles derived from toluene. This work combined with the earlier work on LLPS in SOM particles free of inorganic salts suggests that the occurrence of LLPS in SOM particles free of inorganic salts is related to the oxygen-to-carbon elemental ratio (O : C) of the organic material. These results help explain the difference between the hygroscopic parameter κ of SOM particles measured above and below water saturation in the laboratory and field, and have implications for predicting the cloud condensation nucleation properties of SOM particles.« less

  19. Liquid–liquid phase separation in particles containing secondary organic material free of inorganic salts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Song, Mijung; Liu, Pengfei; Martin, Scot T.

    Particles containing secondary organic material (SOM) are ubiquitous in the atmosphere and play a role in climate and air quality. Recently, research has shown that liquid–liquid phase separation (LLPS) occurs at high relative humidity (RH) (greater than ~95 %) in α-pinene-derived SOM particles free of inorganic salts, while LLPS does not occur in isoprene-derived SOM particles free of inorganic salts. We expand on these findings by investigating LLPS at 290 ± 1 K in SOM particles free of inorganic salts produced from ozonolysis of β-caryophyllene, ozonolysis of limonene, and photo-oxidation of toluene. LLPS was observed at greater than ~95 %more » RH in the biogenic SOM particles derived from β-caryophyllene and limonene while LLPS was not observed in the anthropogenic SOM particles derived from toluene. This work combined with the earlier work on LLPS in SOM particles free of inorganic salts suggests that the occurrence of LLPS in SOM particles free of inorganic salts is related to the oxygen-to-carbon elemental ratio (O : C) of the organic material. These results help explain the difference between the hygroscopic parameter κ of SOM particles measured above and below water saturation in the laboratory and field, and have implications for predicting the cloud condensation nucleation properties of SOM particles.« less

  20. Liquid-liquid phase separation in particles containing secondary organic material free of inorganic salts

    NASA Astrophysics Data System (ADS)

    Song, Mijung; Liu, Pengfei; Martin, Scot T.; Bertram, Allan K.

    2017-09-01

    Particles containing secondary organic material (SOM) are ubiquitous in the atmosphere and play a role in climate and air quality. Recently, research has shown that liquid-liquid phase separation (LLPS) occurs at high relative humidity (RH) (greater than ˜ 95 %) in α-pinene-derived SOM particles free of inorganic salts, while LLPS does not occur in isoprene-derived SOM particles free of inorganic salts. We expand on these findings by investigating LLPS at 290 ± 1 K in SOM particles free of inorganic salts produced from ozonolysis of β-caryophyllene, ozonolysis of limonene, and photo-oxidation of toluene. LLPS was observed at greater than ˜ 95 % RH in the biogenic SOM particles derived from β-caryophyllene and limonene while LLPS was not observed in the anthropogenic SOM particles derived from toluene. This work combined with the earlier work on LLPS in SOM particles free of inorganic salts suggests that the occurrence of LLPS in SOM particles free of inorganic salts is related to the oxygen-to-carbon elemental ratio (O : C) of the organic material. These results help explain the difference between the hygroscopic parameter κ of SOM particles measured above and below water saturation in the laboratory and field, and have implications for predicting the cloud condensation nucleation properties of SOM particles.

  1. A system coupling hybrid biological method with UV/O3 oxidation and membrane separation for treatment and reuse of industrial laundry wastewater.

    PubMed

    Mozia, Sylwia; Janus, Magdalena; Brożek, Piotr; Bering, Sławomira; Tarnowski, Krzysztof; Mazur, Jacek; Morawski, Antoni W

    2016-10-01

    The possibilities of application of a three-step system combining hybrid biological treatment followed by advanced UV/O3 oxidation with in situ generated O3 and membrane separation (ultrafiltration (UF) and nanofiltration (NF)) to treat and reuse the wastewater from an industrial laundry are presented. By the application of a hybrid moving bed biofilm reactor (HMBBR), the total organic carbon concentration was reduced for about 90 %. However, since the HMBBR effluent still contained organic contaminants as well as high concentrations of inorganic ions and exhibited significant turbidity (8.2 NTU), its further treatment before a possible reuse in the laundry was necessary. The UV/O3 pretreatment prior to UF was found to be an efficient method of the membrane fouling alleviation. During UF, the turbidity of wastewater was reduced below 0.3 NTU. To remove the inorganic salts, the UF permeate was further treated during NF. The NF permeate exhibited very low conductivity (27-75 μS/cm) and contained only small amounts of Ca(2+) and Mg(2+); thus ,it could be reused at any stage of the laundry process.

  2. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fain, D.E.

    The conference was an excellent initial forum for coordinating international communication about the rapidly emerging field of inorganic membranes. It was well organized and held in an excellent new conference facility. There were about 300 conferees representing 26 countries, including most of the best known researchers in the field. The quality of the papers was excellent. Many of then presented very new and sophisticated work at the cutting edge of the technology. In Europe and Japan there is a broad awareness of these technologies and techniques for fabricating membranes with a broad range of properties and potential commercial uses. Inmore » his opening plenary paper, J. Charpin, with the Commissariat a L'Energie Atomic (CEA) at Saclay, gave the CEA credit for creating the new generation of inorganic membranes through its technology transfer from their nuclear energy programs. I met and talked with most of the best known people in the field. Our paper was extremely well received. Jacques Gillot hardly spoke to me before the paper. After presenting the paper, he approached me everywhere I went. The visits to the two best known membrane laboratories in Europe were worth the trip alone. Professor Cot's lab in Montpellier is rather modest, but doing some interesting and sophisticated work. Professor Burggraaf's lab in Enschede, Netherlands is extremely well equipped and staffed (63 people), and I believe this lab is doing the most advanced work.« less

  3. Transcriptomic Analysis of Carboxylic Acid Challenge in Escherichia coli: Beyond Membrane Damage

    PubMed Central

    Royce, Liam A.; Boggess, Erin; Fu, Yao; Liu, Ping; Shanks, Jacqueline V.; Dickerson, Julie; Jarboe, Laura R.

    2014-01-01

    Carboxylic acids are an attractive biorenewable chemical. Enormous progress has been made in engineering microbes for production of these compounds though titers remain lower than desired. Here we used transcriptome analysis of Escherichia coli during exogenous challenge with octanoic acid (C8) at pH 7.0 to probe mechanisms of toxicity. This analysis highlights the intracellular acidification and membrane damage caused by C8 challenge. Network component analysis identified transcription factors with altered activity including GadE, the activator of the glutamate-dependent acid resistance system (AR2) and Lrp, the amino acid biosynthesis regulator. The intracellular acidification was quantified during exogenous challenge, but was not observed in a carboxylic acid producing strain, though this may be due to lower titers than those used in our exogenous challenge studies. We developed a framework for predicting the proton motive force during adaptation to strong inorganic acids and carboxylic acids. This model predicts that inorganic acid challenge is mitigated by cation accumulation, but that carboxylic acid challenge inverts the proton motive force and requires anion accumulation. Utilization of native acid resistance systems was not useful in terms of supporting growth or alleviating intracellular acidification. AR2 was found to be non-functional, possibly due to membrane damage. We proposed that interaction of Lrp and C8 resulted in repression of amino acid biosynthesis. However, this hypothesis was not supported by perturbation of lrp expression or amino acid supplementation. E. coli strains were also engineered for altered cyclopropane fatty acid content in the membrane, which had a dramatic effect on membrane properties, though C8 tolerance was not increased. We conclude that achieving higher production titers requires circumventing the membrane damage. As higher titers are achieved, acidification may become problematic. PMID:24586888

  4. Sorption Behavior of Compressed CO2 and CH4 on Ultrathin Hybrid Poly(POSS-imide) Layers.

    PubMed

    Raaijmakers, Michiel J T; Ogieglo, Wojciech; Wiese, Martin; Wessling, Matthias; Nijmeijer, Arian; Benes, Nieck E

    2015-12-09

    Sorption of compressed gases into thin polymeric films is essential for applications including gas sensors and membrane based gas separation. For glassy polymers, the sorption behavior is dependent on the nonequilibrium status of the polymer. The uptake of molecules by a polymer is generally accompanied by dilation, or swelling, of the polymer material. In turn, this dilation can result in penetrant induced plasticization and physical aging that affect the nonequilibrium status of the polymer. Here, we investigate the dilation and sorption behavior of ultrathin membrane layers of a hybrid inorganic-organic network material that consists of alternating polyhedral oligomeric silsesquioxane and imide groups, upon exposure to compressed carbon dioxide and methane. The imide precursor contains fluoroalkene groups that provide affinity toward carbon dioxide, while the octa-functionalized silsesquioxane provides a high degree of cross-linking. This combination allows for extremely high sorption capacities, while structural rearrangements of the network are hindered. We study the simultaneous uptake of gases and dilation of the thin films at high pressures using spectroscopic ellipsometry measurements. Ellipsometry provides the changes in both the refractive index and the film thickness, and allows for accurate quantification of sorption and swelling. In contrast, gravimetric and volumetric measurements only provide a single parameter; this does not allow an accurate correction for, for instance, the changes in buoyancy because of the extensive geometrical changes of highly swelling films. The sorption behavior of the ultrathin hybrid layers depends on the fluoroalkene group content. At low pressure, the apparent molar volume of the gases is low compared to the liquid molar volume of carbon dioxide and methane, respectively. At high gas concentrations in the polymer film, the apparent molar volume of carbon dioxide and methane exceeds that of the liquid molar volume, and approaches that of the gas phase. The high sorption capacity and reversible dilation characteristics of the presented materials provide new directions for applications including gas sensors and gas separation membranes.

  5. Inorganic metal oxide/organic polymer nanocomposites and method thereof

    DOEpatents

    Gash, Alexander E.; Satcher, Joe H.; Simpson, Randy

    2004-03-30

    A synthetic method for preparation of hybrid inorganic/organic energetic nanocomposites is disclosed herein. The method employs the use of stable metal inorganic salts and organic solvents as well as an organic polymer with good solubility in the solvent system to produce novel nanocomposite energetic materials. In addition, fuel metal powders (particularly those that are oxophillic) can be incorporated into composition. This material has been characterized by thermal methods, energy-filtered transmission electron microscopy (EFTEM), N.sub.2 adsoprtion/desorption methods, and Fourier-Transform (FT-IR) spectroscopy. According to these characterization methods the organic polymer phase fills the nanopores of the composite material, providing superb mixing of the component phases in the energetic nanocomposite.

  6. A search for the double-beta decay of Xenon-136 to an excited state of Barium-136 with exo-200

    NASA Astrophysics Data System (ADS)

    Yee, Shannon Koa

    While greater than 80% of all electricity continues to be generated by heat engines, methods of directly converting heat into electricity will remain appealing. Thermoelectric generators are one technology that is capable of doing this but the low efficiency and high cost has limited their terrestrial deployment. Thermoelectrics are compact, solid state devices, without moving parts that directly convert a temperature difference into a voltage. Developing better thermoelectric materials is challenging and requires that materials be engineered with new transport physics. The interface between organic and inorganic materials is one example where new transport physics manifests. Therefore, it is possible that improvements in thermoelectrics can be made by engineering organic-inorganic hybrid thermoelectric materials. Composite materials exhibit characteristics of their constituents where hybrid materials possess new properties that are distinctly different from their constituents. At the interface between organic and inorganic materials, hybrid properties manifest. One ideal system to understand this interface is in a metal-molecule-metal junction commonly referred to as a molecular junction. This is often a result of the discrete electronic energy levels of the organic hybridizing with the continuum of electronic states in the inorganic. Herein, new transport phenomenon is observed in molecular junctions, which have great promise for thermoelectrics. It is observed that the transport property are positively correlated breaking the historic trends to improving thermoelectric efficiency. Towards the goal of higher efficiency thermoelectrics, the fundamental science of interfaces is first investigated in molecular junctions. Guiding principles from these fundamental studies are then applied to engineer a bulk, polymer-based, thermoelectric materials with high efficiency. These improvements are encouraging and motivated a cost analysis to evaluate their current market potential against competing thermoelectric materials. In all, this dissertation marks the progress in developing a new class of hybrid organic-inorganic materials for thermoelectric applications.

  7. Proton conductivity and methanol permeability of Nafion-SiO2/SiWA composite membranes

    NASA Astrophysics Data System (ADS)

    Thiam, Hui San; Chia, Min Yan; Cheah, Qiao Rou; Koo, Charlene Chai Hoon; Lai, Soon Onn; Chong, Kok Chung

    2017-04-01

    Proton exchange membranes for a direct methanol fuel cell (DMFC) were prepared by incorporating silica/silicotungstic acid (SiO2/SiWA) inorganic composite into a Nafion polymer. The effects of SiO2/SiWA content on proton conductivity of membranes were investigated by using a four-probe conductivity cell. Methanol permeability of composite membrane was also determined by using a homemade diffusion cell and gas chromatography technique. It was found that proton conductivity of the composite membranes decreased with SiO2/SiWA content, however the highest proton conductivity achieved was 11% greater than the pure recast Nafion membrane. The methanol permeability of composite membrane was much lower than that of pure recast Nafion, in a reduction of 58% which indicated a better resistance to fuel crossover. Nafion-SiO2/SiWA composite membrane showed promising advantages over pure Nafion on electrochemical properties such as proton conductivity and fuel crossover and it is potentially attractive for use in DMFC.

  8. Ammonia recovery from agricultural wastes by membrane distillation: fouling characterization and mechanism.

    PubMed

    Zarebska, A; Nieto, D Romero; Christensen, K V; Norddahl, B

    2014-06-01

    One of the main obstacles impeding implementation of membrane distillation for the recovery and concentration of ammonia from swine manure is wetting caused by fouling. Due to the different types of fouling which can occur in a membrane system, foulants characterization is a complex problem. To elucidate the fouling mechanism, deposit morphology and composition of foulants have been determined using Scanning Electron Microscopy, X-ray Energy Dispersive Spectrometry, Attenuated Total Reflectance Infrared Spectrometry, Ion chromatography and Inductively coupled plasma-optical emission spectroscopy. Based on the analysis of fouled membranes, it is concluded that membrane fouling is dominated by organic fouling in combination with deposits of inorganic elements and microorganisms. After a week of running the membrane process without cleaning, the average fouling layer thickness was estimated to 10-15 μm. The fouling layer further results in a loss of membrane hydrophobicity. This indicates that fouling could be a severe problem for membrane distillation performance. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Report of the Polymer Core Course Committee: Inclusion of Polymer Topics into Undergraduate Inorganic Chemistry Courses.

    ERIC Educational Resources Information Center

    Miller, Norman E.; And Others

    1984-01-01

    Suggests polymer topics for study in inorganic chemistry courses. Commercial materials (including list of inorganic compounds utilized in polymer industry), anchored metal catalysis, polymers modified or formed by coordination, polysiloxanes, phosphazene or phosphonitrilic halide polymers, and hetergeneous polymerization catalysts are considered.…

  10. Acquisition of an Advanced Thermal Analysis andImaging System for Integration with Interdisciplinary Researchand Education in Low Density Organic Inorganic Materials

    DTIC Science & Technology

    2017-12-02

    Report: Acquisition of an Advanced Thermal Analysis and Imaging System for Integration with Interdisciplinary Research and Education in Low Density...for Integration with Interdisciplinary Research and Education in Low Density Organic-Inorganic Materials Report Term: 0-Other Email: dmisra2

  11. Chemically Integrated Inorganic-Graphene Two-Dimensional Hybrid Materials for Flexible Energy Storage Devices.

    PubMed

    Peng, Lele; Zhu, Yue; Li, Hongsen; Yu, Guihua

    2016-12-01

    State-of-the-art energy storage devices are capable of delivering reasonably high energy density (lithium ion batteries) or high power density (supercapacitors). There is an increasing need for these power sources with not only superior electrochemical performance, but also exceptional flexibility. Graphene has come on to the scene and advancements are being made in integration of various electrochemically active compounds onto graphene or its derivatives so as to utilize their flexibility. Many innovative synthesis techniques have led to novel graphene-based hybrid two-dimensional nanostructures. Here, the chemically integrated inorganic-graphene hybrid two-dimensional materials and their applications for energy storage devices are examined. First, the synthesis and characterization of different kinds of inorganic-graphene hybrid nanostructures are summarized, and then the most relevant applications of inorganic-graphene hybrid materials in flexible energy storage devices are reviewed. The general design rules of using graphene-based hybrid 2D materials for energy storage devices and their current limitations and future potential to advance energy storage technologies are also discussed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Insights into the Interactions of Amino Acids and Peptides with Inorganic Materials Using Single-Molecule Force Spectroscopy.

    PubMed

    Das, Priyadip; Duanias-Assaf, Tal; Reches, Meital

    2017-03-06

    The interactions between proteins or peptides and inorganic materials lead to several interesting processes. For example, combining proteins with minerals leads to the formation of composite materials with unique properties. In addition, the undesirable process of biofouling is initiated by the adsorption of biomolecules, mainly proteins, on surfaces. This organic layer is an adhesion layer for bacteria and allows them to interact with the surface. Understanding the fundamental forces that govern the interactions at the organic-inorganic interface is therefore important for many areas of research and could lead to the design of new materials for optical, mechanical and biomedical applications. This paper demonstrates a single-molecule force spectroscopy technique that utilizes an AFM to measure the adhesion force between either peptides or amino acids and well-defined inorganic surfaces. This technique involves a protocol for attaching the biomolecule to the AFM tip through a covalent flexible linker and single-molecule force spectroscopy measurements by atomic force microscope. In addition, an analysis of these measurements is included.

  13. A robust and stretchable superhydrophobic PDMS/PVDF@KNFs membrane for oil/water separation and flame retardancy.

    PubMed

    Li, Deke; Gou, Xuelian; Wu, Daheng; Guo, Zhiguang

    2018-04-05

    The wide application of superhydrophobic membranes has been limited due to their complicated preparation technology and weak durability. Inspired by the mechanical flexibility of nanofibrous biomaterials, nanofibrils have been successfully generated from Kevlar, which is one of the strongest synthetic fibers, by appropriate hydrothermal treatment. In this study, a robust superhydrophobic PDMS/PVDF@KNFs membrane is prepared via a simple one-step process and subsequent curing without combination with inorganic fillers. The as-prepared PDMS/PVDF@KNFs membrane not only shows efficient oil/water separation ability and oil absorption capacity but also has excellent superhydrophobicity stability after deformation. The resultant membrane shows stretchability, flexibility and flame retardance because of the reinforcing effect and the excellent flame retardancy of Kevlar. We believe that this simple fabrication of PDMS/PVDF@KNFs has promising applications in filtering membranes and wearable devices.

  14. Supported liquid inorganic membranes for nuclear waste separation

    DOEpatents

    Bhave, Ramesh R; DeBusk, Melanie M; DelCul, Guillermo D; Delmau, Laetitia H; Narula, Chaitanya K

    2015-04-07

    A system and method for the extraction of americium from radioactive waste solutions. The method includes the transfer of highly oxidized americium from an acidic aqueous feed solution through an immobilized liquid membrane to an organic receiving solvent, for example tributyl phosphate. The immobilized liquid membrane includes porous support and separating layers loaded with tributyl phosphate. The extracted solution is subsequently stripped of americium and recycled at the immobilized liquid membrane as neat tributyl phosphate for the continuous extraction of americium. The sequestered americium can be used as a nuclear fuel, a nuclear fuel component or a radiation source, and the remaining constituent elements in the aqueous feed solution can be stored in glassified waste forms substantially free of americium.

  15. Novel sol-gel organic-inorganic hybrid materials for drug delivery.

    PubMed

    Catauro, Michelina; Verardi, Duilio; Melisi, Daniela; Belotti, Federico; Mustarelli, Piercarlo

    2010-01-01

    The aim of the present study was to synthetize and characterize novel sol-gel organic-inorganic hybrid materials to be used for controlled drug delivery application. Organic-inorganic hybrid class I materials based on poly(epsilon-caprolactone) (PCL 6, 12, 24 and 50 wt%) and zirconia-yttria (ZrO2-5%Y2O3) were synthesized by a sol-gel method, from a multicomponent solution containing zirconium propoxide [Zr(OC2H7)4], yttrium chloride (YCl3), PCL, water and chloroform (CHCl3). The structure of the hybrids was obtained by means of hydrogen bonds between the Zr-OH group (H-donor) in the sol-gel intermediate species and the carboxylic group (H-acceptor) in the repeating units of the polymer. The presence of hydrogen bonds between organic-inorganic components of the hybrid materials was suggested by Fourier transform infrared (FTIR) analysis, and strongly supported by solid-state NMR. A single-step, sol-gel process was then used to precipitate microspheres containing ketoprofen or indomethacin for controlled drug delivery applications. Release kinetics in a simulated body fluid (SBF) were subsequently investigated. The amount of drug released was detected by UV-VIS spectroscopy. Pure anti-inflammatory agents exhibited linear release with time, in contrast drugs entrapped in the organic-inorganic hybrids were released with a logarithmic time dependence, starting with an initial burst effect followed by a gradual decrease. The synthesis of amorphous materials containing drugs, obtained by sol-gel methods, helps to devise new strategies for controlled drug delivery system design.

  16. Organic-Inorganic Composites Toward Biomaterial Application.

    PubMed

    Miyazaki, Toshiki; Sugawara-Narutaki, Ayae; Ohtsuki, Chikara

    2015-01-01

    Bioactive ceramics are known to exhibit specific biological affinities and are able to show direct integration with surrounding bone when implanted in bony defects. However, their inadequate mechanical properties, such as low fracture toughness and high Young's modulus in comparison to natural bone, limit their clinical application. Bone is a kind of organic-inorganic composite where apatite nanocrystals are precipitated onto collagen fibre networks. Thus, one way to address these problems is to mimic the natural composition of bone by using bioactive ceramics via material designs based on organic-inorganic composites. In this chapter, the current research on the development of the various organic-inorganic composites designed for biomaterial applications has been reviewed. Various compounds such as calcium phosphate, calcium sulphate and calcium carbonate can be used for the inorganic phases to design composites with the desired mechanical and biological properties of bone. Not only classical mechanical mixing but also coating of the inorganic phase in aqueous conditions is available for the fabrication of such composites. Organic modifications using various polymers enable the control of the crystalline structure of the calcium carbonate in the composites. These approaches on the fabrication of organic-inorganic composites provide important options for biomedical materials with novel functions. © 2015 S. Karger AG, Basel.

  17. Biotemplated synthesis of inorganic materials: An emerging paradigm for nanomaterial synthesis inspired by nature

    DOE PAGES

    Krajina, Brad A.; Proctor, Amy C.; Schoen, Alia P.; ...

    2017-08-08

    Biomineralization, the process by which biological systems direct the synthesis of inorganic structures from organic templates, is an exquisite example of nanomaterial self-assembly in nature. Its products include the shells of mollusks and the bones and teeth of vertebrates. By comparison, conventional inorganic synthesis techniques provide limited control over inorganic nanomaterial architecture. Inspired by biomineralization in nature, over the last two decades, the field of biotemplating has emerged as a new paradigm for inorganic nanomaterial assembly, wherein researchers seek to design novel nano-structures in which inorganic nanomaterial synthesis is directed from an underlying biomolecular template. Here, we review the motivation,more » mechanistic understanding, progress, and challenges for the field of biotemplating. We highlight the interdisciplinary nature of this field, and survey a broad range of examples of bio-templated engineering: ranging from strategies that exploit the inherent capabilities of proteins in nature, to genetically-engineered systems that unlock new capabilities for self-assembly with biomolecules. Here, we illustrate that the use of biological materials as templates for inorganic self-assembly holds tremendous potential for nanomaterial engineering, with applications that range from electronics and energy to medicine.« less

  18. Biotemplated synthesis of inorganic materials: An emerging paradigm for nanomaterial synthesis inspired by nature

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krajina, Brad A.; Proctor, Amy C.; Schoen, Alia P.

    Biomineralization, the process by which biological systems direct the synthesis of inorganic structures from organic templates, is an exquisite example of nanomaterial self-assembly in nature. Its products include the shells of mollusks and the bones and teeth of vertebrates. By comparison, conventional inorganic synthesis techniques provide limited control over inorganic nanomaterial architecture. Inspired by biomineralization in nature, over the last two decades, the field of biotemplating has emerged as a new paradigm for inorganic nanomaterial assembly, wherein researchers seek to design novel nano-structures in which inorganic nanomaterial synthesis is directed from an underlying biomolecular template. Here, we review the motivation,more » mechanistic understanding, progress, and challenges for the field of biotemplating. We highlight the interdisciplinary nature of this field, and survey a broad range of examples of bio-templated engineering: ranging from strategies that exploit the inherent capabilities of proteins in nature, to genetically-engineered systems that unlock new capabilities for self-assembly with biomolecules. Here, we illustrate that the use of biological materials as templates for inorganic self-assembly holds tremendous potential for nanomaterial engineering, with applications that range from electronics and energy to medicine.« less

  19. An Autopsy of Nanofiltration Membrane Used for Landfill Leachate Treatment

    PubMed Central

    Demir, Ibrahim; Koyuncu, Ismail; Guclu, Serkan; Yildiz, Senol; Balahorli, Vahit; Caglar, Suphi; Turken, Turker; Pasaoglu, Mehmet E.; Kaya, Recep; Sengur-Tasdemir, Reyhan

    2015-01-01

    Komurcuoda leachate treatment plant, Istanbul, which consists of membrane bioreactor (MBR) and nanofiltration (NF) system, faced rapid flux decline in membranes after 3-year successful operation. To compensate rapid flux decline in membranes, the fouled membranes were renewed but replacement of the membranes did not solve the problem. To find the reasons and make a comprehensive analysis, membrane autopsy was performed. Visual and physical inspection of the modules and some instrumental analysis were conducted for membrane autopsy. Membranes were found severely fouled with organic and inorganic foulants. Main foulant was iron which was deposited on surface. The main reason was found to be the changing of aerator type of MBR. When surface aerators were exchanged with bottom diffusers which led to increasing of dissolved oxygen (DO) level of the basin, iron particles were oxidized and they converted into particulate insoluble form. It was thought that probably this insoluble form of the iron particles was the main cause of decreased membrane performance. After the diagnosis, a new pretreatment alternative including a new iron antiscalant was suggested and system performance has been recovered. PMID:26137593

  20. USING MEMBRANES TO CONCENTRATE DISINFECTION BYPRODUCTS FOR SUBSEQUENT HEALTH EFFECTS STUDIES

    EPA Science Inventory

    Chemical disinfection of water is a major public health advance that has decreased dramatically water-borne disease. Disinfecting agents react with naturally occurring organic and inorganic matter in water to produce a wide variety of disinfection byproducts (DBPs). Although mo...

  1. Synthesis and characterization of microporous inorganic membranes for propylene/propane separation

    NASA Astrophysics Data System (ADS)

    Ma, Xiaoli

    Membrane-based gas separation is promising for efficient propylene/propane (C3H6/C3H8) separation with low energy consumption and minimum environment impact. Two microporous inorganic membrane candidates, MFI-type zeolite membrane and carbon molecular sieve membrane (CMS) have demonstrated excellent thermal and chemical stability. Application of these membranes into C3H6/C3H 8 separation has not been well investigated. This dissertation presents fundamental studies on membrane synthesis, characterization and C3H 6/C3H8 separation properties of MFI zeolite membrane and CMS membrane. MFI zeolite membranes were synthesized on α-alumina supports by secondary growth method. Novel positron annihilation spectroscopy (PAS) techniques were used to non-destructively characterize the pore structure of these membranes. PAS reveals a bimodal pore structure consisting of intracrystalline zeolitic micropores of ~0.6 nm in diameter and irregular intercrystalline micropores of 1.4 to 1.8 nm in size for the membranes. The template-free synthesized membrane exhibited a high permeance but a low selectivity in C3H 6/C3H8 mixture separation. CMS membranes were synthesized by coating/pyrolysis method on mesoporous gamma-alumina support. Such supports allow coating of thin, high-quality polymer films and subsequent CMS membranes with no infiltration into support pores. The CMS membranes show strong molecular sieving effect, offering a high C3H 6/C3H8 mixture selectivity of ~30. Reduction in membrane thickness from 500 nm to 300 nm causes an increase in C3H8 permeance and He/N2 selectivity, but a decrease in the permeance of He, N 2 and C3H6 and C3H6/C 3H8 selectivity. This can be explained by the thickness dependent chain mobility of the polymer film resulting in final carbon membrane of reduced pore size with different effects on transport of gas of different sizes, including possible closure of C3H6-accessible micropores. CMS membranes demonstrate excellent C3H6/C 3H8 separation performance over a wide range of feed pressure, composition and operation temperature. No plasticization was observed at a feed pressure up to 100 psi. The permeation and separation is mainly controlled by diffusion instead of adsorption. CMS membrane experienced a decline in permeance, and an increase in selectivity over time under on-stream C 3H6/C3H8 separation. This aging behavior is due to the reduction in effective pore size and porosity caused by oxygen chemisorption and physical aging of the membrane structure.

  2. Simulating the effects of light intensity and carbonate system composition on particulate organic and inorganic carbon production in Emiliania huxleyi.

    PubMed

    Holtz, Lena-Maria; Wolf-Gladrow, Dieter; Thoms, Silke

    2015-05-07

    Coccolithophores play an important role in the marine carbon cycle. Variations in light intensity and external carbonate system composition alter intracellular carbon fluxes and therewith the production rates of particulate organic and inorganic carbon. Aiming to find a mechanistic explanation for the interrelation between dissolved inorganic carbon fluxes and particulate carbon production rates, we develop a numerical cell model for Emiliania huxleyi, one of the most abundant coccolithophore species. The model consists of four cellular compartments, for each of which the carbonate system is resolved dynamically. The compartments are connected to each other and to the external medium via substrate fluxes across the compartment-confining membranes. By means of the model we are able to explain several pattern observed in particulate organic and inorganic carbon production rates for different strains and under different acclimation conditions. Particulate organic and inorganic carbon production rates for instance decrease at very low external CO2 concentrations. Our model suggests that this effect is caused mainly by reduced HCO3(-) uptake rates, not by CO2 limitation. The often observed decrease in particulate inorganic carbon production rates under Ocean Acidification is explained by a downregulation of cellular HCO3(-) uptake. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Review on Polymers for Thermoelectric Applications

    PubMed Central

    Culebras, Mario; Gómez, Clara M.; Cantarero, Andrés

    2014-01-01

    In this review, we report the state-of-the-art of polymers in thermoelectricity. Classically, a number of inorganic compounds have been considered as the best thermoelectric materials. Since the prediction of the improvement of the figure of merit by means of electronic confinement in 1993, it has been improved by a factor of 3–4. In the mean time, organic materials, in particular intrinsically conducting polymers, had been considered as competitors of classical thermoelectrics, since their figure of merit has been improved several orders of magnitude in the last few years. We review here the evolution of the figure of merit or the power factor during the last years, and the best candidates to compete with inorganic materials. We also outline the best polymers to substitute classical thermoelectric materials and the advantages they present in comparison with inorganic systems. PMID:28788208

  4. Contaminated water treatment

    NASA Technical Reports Server (NTRS)

    Gormly, Sherwin J. (Inventor); Flynn, Michael T. (Inventor)

    2010-01-01

    Method and system for processing of a liquid ("contaminant liquid") containing water and containing urine and/or other contaminants in a two step process. Urine, or a contaminated liquid similar to and/or containing urine and thus having a relatively high salt and urea content is passed through an activated carbon filter to provide a resulting liquid, to remove most of the organic molecules. The resulting liquid is passed through a semipermeable membrane from a membrane first side to a membrane second side, where a fortified drink having a lower water concentration (higher osmotic potential) than the resulting liquid is positioned. Osmotic pressure differential causes the water, but not most of the remaining inorganic (salts) contaminant(s) to pass through the membrane to the fortified drink. Optionally, the resulting liquid is allowed to precipitate additional organic molecules before passage through the membrane.

  5. Role of Inherent Inorganic Constituents in SO2 Sorption Ability of Biochars Derived from Three Biomass Wastes.

    PubMed

    Xu, Xiaoyun; Huang, Daxuan; Zhao, Ling; Kan, Yue; Cao, Xinde

    2016-12-06

    Biochar is rich in both organic carbon and inorganic components. Extensive work has attributed the high sorption ability of biochar to the pore structure and surface chemical property related to its organic carbon fraction. In this study, three biochars derived from dairy manure (DM-biochar), sewage sludge (SS-biochar), and rice husk (RH-biochar), respectively, were evaluated for their SO 2 sorption behavior and the underlying mechanisms, especially the role of inherent inorganic constituents. The sorption capacities of SO 2 by the three biochars were 8.87-15.9 mg g -1 . With the moisture content increasing from 0% to 50%, the sorption capacities increased by up to about 3 times, mainly due to the formation of alkaline water membrane on the biochar surface which could promote the sorption and transformation of acidic SO 2 . DM- and SS-biochar containing larger mineral constituents showed higher sorption capacity for SO 2 than RH-biochar containing less mineral components. CaCO 3 and Ca 3 (PO 4 ) 2 in DM-biochar induced sorbed SO 2 transformation into K 2 Ca(SO 4 ) 2 ·H 2 O and CaSO 4 ·2H 2 O, while the sorbed SO 2 was converted to Fe 2 (SO 4 ) 3 ·H 2 SO 4 ·2H 2 O, CaSO 4 ·2H 2 O, and Ca 3 (SO 3 ) 2 SO 4 ·12H 2 O in SS-biochar. For RH-biochar, K 3 H(SO 4 ) 2 might exist in the exhausted samples. Overall, the chemical transformation of SO 2 induced by biochar inherent mineral components occupied 44.6%-85.5% of the total SO 2 sorption. The results obtained from this study demonstrated that biochar as a unique carbonaceous material could distinctly be a promising sorbent for acidic SO 2 removal in which the inorganic components played an important role in the SO 2 sorption and transformation.

  6. Inorganic-Organic Polymers and Their Role in Materials Science

    DTIC Science & Technology

    1994-05-18

    North Quincy Street AD-A279 715 Arlington, Virginia 22217-5000 H IM 11. SUPPLEMENTARY NOTES Prepared for publication in ADVAtICED MlATERIALS 12a...This document has been approved for public release; distribution is unlimited. 13. ABSTRACT (Maximum 200 words) The design and synthesis of new...Technical Report No. 19 INORGANIC-ORGANIC POLYMERS AND THEIR ROLE IN MATERIALS SCIENCE by Harry R. Allcock Prepared for Publication in Advanced Materials

  7. Dispersions of Aramid Nanofibers: A New Nanoscale Building Block

    PubMed Central

    Yang, Ming; Cao, Keqin; Sui, Lang; Qi, Ying; Zhu, Jian; Waas, Anthony; Arruda, Ellen M.; Kieffer, John; Thouless, M. D.; Kotov, Nicholas A.

    2011-01-01

    Stable dispersions of nanofibers are virtually unknown for synthetic polymers. They can complement analogous dispersions of inorganic components, such as nanoparticles, nanowires, nanosheets, etc as a fundamental component of a toolset for design of nanostructures and metamaterials via numerous solvent-based processing methods. As such, strong flexible polymeric nanofibers are very desirable for the effective utilization within composites of nanoscale inorganic components such as nanowires, carbon nanotubes, graphene, and others. Here stable dispersions of uniform high-aspect-ratio aramid nanofibers (ANFs) with diameters between 3 and 30 nm and up to 10 μm in length were successfully obtained. Unlike the traditional approaches based on polymerization of monomers, they are made by controlled dissolution of standard macroscale form of the aramid polymer, i.e. well known Kevlar threads, and revealed distinct morphological features similar to carbon nanotubes. ANFs are successfully processed into films using layer-by-layer (LBL) assembly as one of the potential methods of preparation of composites from ANFs. The resultant films are transparent and highly temperature resilient. They also display enhanced mechanical characteristics making ANF films highly desirable as protective coatings, ultrastrong membranes, as well as building blocks of other high performance materials in place of or in combination with carbon nanotubes. PMID:21800822

  8. Sulfur-Containing Organic-Inorganic Hybrid Gel Compositions and Aerogels

    NASA Technical Reports Server (NTRS)

    Evans, Owen R (Inventor); Deshpande, Kiranmayi (Inventor); Dong, Wenting (Inventor)

    2017-01-01

    Methods and materials are described for preparing organic-inorganic hybrid gel compositions where a sulfur-containing cross-linking agent covalently links the organic and inorganic components. The gel compositions are further dried to provide porous gel compositions and aerogels. The mechanical and thermal properties of the dried gel compositions are also disclosed.

  9. Sulfur-Containing Organic-Inorganic Hybrid Gel Compositions and Aerogels

    NASA Technical Reports Server (NTRS)

    Deshpande, Kiranmayi (Inventor); Evans, Owen R. (Inventor); Dong, Wenting (Inventor)

    2015-01-01

    Methods and materials are described for preparing organic-inorganic hybrid gel compositions where a sulfur-containing cross-linking agent covalently links the organic and inorganic components. The gel compositions are further dried to provide porous gel compositions and aerogels. The mechanical and thermal properties of the dried gel compositions are also disclosed.

  10. 46 CFR 151.50-20 - Inorganic acids.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Inorganic acids. 151.50-20 Section 151.50-20 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-20 Inorganic acids. (a)(1) Gravity..., but in no case shall the design pressure be less than that indicated as follows: Fluorosilicic Acid—50...

  11. 46 CFR 151.50-20 - Inorganic acids.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Inorganic acids. 151.50-20 Section 151.50-20 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-20 Inorganic acids. (a)(1) Gravity..., but in no case shall the design pressure be less than that indicated as follows: Fluorosilicic Acid—50...

  12. Design and synthesis of organic-inorganic hybrid capsules for biotechnological applications.

    PubMed

    Shi, Jiafu; Jiang, Yanjun; Wang, Xiaoli; Wu, Hong; Yang, Dong; Pan, Fusheng; Su, Yanlei; Jiang, Zhongyi

    2014-08-07

    Organic-inorganic hybrid capsules, which typically possess a hollow lumen and a hybrid wall, have emerged as a novel and promising class of hybrid materials and have attracted enormous attention. In comparison to polymeric capsules or inorganic capsules, the hybrid capsules combine the intrinsic physical/chemical properties of the organic and inorganic moieties, acquire more degrees of freedom to manipulate multiple interactions, create hierarchical structures and integrate multiple functionalities. Thus, the hybrid capsules exhibit superior mechanical strength (vs. polymeric capsules) and diverse functionalities (vs. inorganic capsules), which may give new opportunities to produce high-performance materials. Much effort has been devoted to exploring innovative and effective methods for the synthesis of hybrid capsules that exhibit desirable performance in target applications. This tutorial review firstly presents a brief description of the capsular structure and hybrid materials in nature, then classifies the hybrid capsules into molecule-hybrid capsules and nano-hybrid capsules based upon the size of the organic and inorganic moieties in the capsule wall, followed by a detailed discussion of the design and synthesis of the hybrid capsules. For each kind of hybrid capsule, the state-of-the-art synthesis methods are described in detail and a critical comment is embedded. The applications of these hybrid capsules in biotechnological areas (biocatalysis, drug delivery, etc.) have also been summarized. Hopefully, this review will offer a perspective and guidelines for the future research and development of hybrid capsules.

  13. INVESTIGATION OF INORGANIC PHOTOTROPIC MATERIALS AS A BI-OPTIC ELEMENT APPLICABLE IN HIGH DENSITY STORAGE COMPUTER MEMORIES

    DTIC Science & Technology

    A general valuation of the various types of phototropic (i.e., reversible, light induced, color producing) phenomenon is given regarding the...application of phototropic material to bioptic high density storage media for compu er memories. The inorganic ’’F’’ center type phototropic systems were

  14. Annual Technical Report, Materials Research Laboratory, 1 July 1984 - 30 June 1986.

    DTIC Science & Technology

    1986-06-30

    4 -’ Section 2 -Inorganic Glasses , Introduction ....... ........... ........................... 54 Research Results...Inorganic Glasses (coordinated by W. M. Risen, Jr.) Surfaces (coordinated by P. J. Estrup). In addition, MRL supported thrce New Initiatives: Physical...on a series of closely related " phenomena in two-phase polycrystalline materials, single crystals and metallic glasses . Although these research

  15. Gas sensing in 2D materials

    NASA Astrophysics Data System (ADS)

    Yang, Shengxue; Jiang, Chengbao; Wei, Su-huai

    2017-06-01

    Two-dimensional (2D) layered inorganic nanomaterials have attracted huge attention due to their unique electronic structures, as well as extraordinary physical and chemical properties for use in electronics, optoelectronics, spintronics, catalysts, energy generation and storage, and chemical sensors. Graphene and related layered inorganic analogues have shown great potential for gas-sensing applications because of their large specific surface areas and strong surface activities. This review aims to discuss the latest advancements in the 2D layered inorganic materials for gas sensors. We first elaborate the gas-sensing mechanisms and introduce various types of gas-sensing devices. Then, we describe the basic parameters and influence factors of the gas sensors to further enhance their performance. Moreover, we systematically present the current gas-sensing applications based on graphene, graphene oxide (GO), reduced graphene oxide (rGO), functionalized GO or rGO, transition metal dichalcogenides, layered III-VI semiconductors, layered metal oxides, phosphorene, hexagonal boron nitride, etc. Finally, we conclude the future prospects of these layered inorganic materials in gas-sensing applications.

  16. Flexible inorganic light emitting diodes based on semiconductor nanowires

    PubMed Central

    Guan, Nan; Dai, Xing; Babichev, Andrey V.; Julien, François H.

    2017-01-01

    The fabrication technologies and the performance of flexible nanowire light emitting diodes (LEDs) are reviewed. We first introduce the existing approaches for flexible LED fabrication, which are dominated by organic technologies, and we briefly discuss the increasing research effort on flexible inorganic LEDs achieved by micro-structuring and transfer of conventional thin films. Then, flexible nanowire-based LEDs are presented and two main fabrication technologies are discussed: direct growth on a flexible substrate and nanowire membrane formation and transfer. The performance of blue, green, white and bi-color flexible LEDs fabricated following the transfer approach is discussed in more detail. PMID:29568439

  17. Heat resistant substrates and battery separators made therefrom

    NASA Technical Reports Server (NTRS)

    Langer, Alois (Inventor); Scala, Luciano C. (Inventor); Ruffing, Charles R. (Inventor)

    1976-01-01

    A flexible substrate having a caustic resistant support and at least one membrane comprising a solid polymeric matrix containing a network of interconnected pores and interdispersed inorganic filler particles with a ratio of filler: polymer in the polymeric matrix of between about 1:1 to 5:1, is made by coating at least one side of the support with a filler:coating formulation mixture of inorganic filler particles and a caustic resistant, water insoluble polymer dissolved in an organic solvent, and removing the solvent from the mixture to provide a porous network within the polymeric matrix.

  18. Visualization of Iron-Binding Micelles in Acidic Recombinant Biomineralization Protein, MamC

    DOE PAGES

    Kashyap, Sanjay; Woehl, Taylor; Valverde-Tercedor, Carmen; ...

    2014-01-01

    Biological macromolecules are utilized in low-temperature synthetic methods to exert precise control over nanoparticle nucleation and placement. They enable low-temperature formation of a variety of functional nanostructured materials with properties often not achieved via conventional synthetic techniques. Here we report on the in situ visualization of a novel acidic bacterial recombinant protein, MamC, commonly present in the magnetosome membrane of several magnetotactic bacteria, including Magnetococcus marinus , strain MC-1. Our findings provide an insight into the self-assembly of MamC and point to formation of the extended protein surface, which is assumed to play an important role in the formation ofmore » biotemplated inorganic nanoparticles. The self-organization of MamC is compared to the behavior of another acidic recombinant iron-binding protein, Mms6.« less

  19. Visualization of Iron-Binding Micelles in Acidic Recombinant Biomineralization Protein, MamC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kashyap, Sanjay; Woehl, Taylor; Valverde-Tercedor, Carmen

    2014-03-07

    Biological macromolecules are utilized in low-temperature synthetic methods to exert precise control over nanoparticle nucleation and placement. They enable low-temperature formation of a variety of functional nanostructured materials with properties often not achieved via conventional synthetic techniques. Here we report on the in situ visualization of a novel acidic bacterial recombinant protein, MamC, commonly present in the magnetosome membrane of several magnetotactic bacteria, including Magnetococcus marinus, strain MC-1. Our findings provide an insight into the self-assembly of MamC and point to formation of the extended protein surface, which is assumed to play an important role in the formation of biotemplatedmore » inorganic nanoparticles. The self-organization of MamC is compared to the behavior of another acidic recombinant iron-binding protein, Mms6.« less

  20. Water recovery in a concentrated solar power plant

    NASA Astrophysics Data System (ADS)

    Raza, Aikifa; Higgo, Alex R.; Alobaidli, Abdulaziz; Zhang, TieJun

    2016-05-01

    For CSP plants, water consumption is undergoing increasing scrutiny particularly in dry and arid regions with water scarcity conditions. Significant amount of water has to be used for parabolic trough mirror cleaning to maintain high mirror reflectance and optical efficiency in sandy environment. For this specific purpose, solar collectors are washed once or twice every week at Shams 1, one of the largest CSP plant in the Middle East, and about 5 million gallons of demineralized water is utilized every year without further recovery. The produced waste water from a CSP plant contains the soiling i.e. accumulated dust and some amount of organic contaminants, as indicated by our analysis of waste water samples from the solar field. We thus need to develop a membrane based system to filter fine dust particulates and to degrade organic contaminant simultaneously. Membrane filtration technology is considered to be cost-effective way to address the emerging problem of a clean water shortage, and to reuse the filtered water after cleaning solar collectors. But there are some major technical barriers to improve the robustness and energy efficiency of filtration membranes especially when dealing with the removal of ultra-small particles and oil traces. Herein, we proposed a robust and scalable nanostructured inorganic microporous filtration copper mesh. The inorganic membrane surface wettability is tailored to enhance the water permeability and filtration flux by creating nanostructures. These nanostructured membranes were successfully employed to recover water collected after cleaning the reflectors of solar field of Shams 1. Another achievement was to remove the traces of heat transfer fluid (HTF) from run-off water which was collected after accidental leakage in some of the heat exchangers during the commissioning of the Shams 1 for safe disposal into the main stream. We hope, by controlling the water recovery factor and membrane reusability performance, the membrane design could be used for water conservation in CSP plants.

  1. Sensitivity of Hollow Fiber Spacesuit Water Membrane Evaporator Systems to Potable Water Constituents, Contaminants and Air Bubbles

    NASA Technical Reports Server (NTRS)

    Bue, Grant C.; Trevino, Luis A.; Fritts, Sharon; Tsioulos, Gus

    2008-01-01

    The Spacesuit Water Membrane Evaporator (SWME) is the baseline heat rejection technology selected for development for the Constellation lunar suit. The first SWME prototype, designed, built, and tested at Johnson Space Center in 1999 used a Teflon hydrophobic porous membrane sheet shaped into an annulus to provide cooling to the coolant loop through water evaporation to the vacuum of space. This present study describes the test methodology and planning and compares the test performance of three commercially available hollow fiber materials as alternatives to the sheet membrane prototype for SWME, in particular, a porous hydrophobic polypropylene, and two variants that employ ion exchange through non-porous hydrophilic modified Nafion. Contamination tests will be performed to probe for sensitivities of the candidate SWME elements to ordinary constituents that are expected to be found in the potable water provided by the vehicle, the target feedwater source. Some of the impurities in potable water are volatile, such as the organics, while others, such as the metals and inorganic ions are nonvolatile. The non-volatile constituents will concentrate in the SWME as evaporated water from the loop is replaced by the feedwater. At some point in the SWME mission lifecycle as the concentrations of the non-volatiles increase, the solubility limits of one or more of the constituents may be reached. The resulting presence of precipitate in the coolant water may begin to plug pores and tube channels and affect the SWME performance. Sensitivity to macroparticles, lunar dust simulant, and air bubbles will also be investigated.

  2. NANOFILTRATION FOULANTS FROM A TREATED SURFACE WATER

    EPA Science Inventory

    The foulant from pilot nanofiltration membrane elements fed conventionally-treated surface water for 15 months was analyzed for organic, inorganic, and biological parameters. The foulant responsible for flux loss was shown to be a film layer 20 to 80 um thick with the greatest de...

  3. New insights into comparison between synthetic and practical municipal wastewater in cake layer characteristic analysis of membrane bioreactor.

    PubMed

    Zhou, Lijie; Zhuang, Wei-Qin; Wang, Xin; Yu, Ke; Yang, Shufang; Xia, Siqing

    2017-11-01

    In previous studies, cake layer analysis in membrane bioreactor (MBR) was both carried out with synthetic and practical municipal wastewater (SMW and PMW), leading to different results. This study aimed to identify the comparison between SMW and PMW in cake layer characteristic analysis of MBR. Two laboratory-scale anoxic/oxic MBRs were operated for over 90days with SMW and PMW, respectively. Results showed that PMW led to rough cake layer surface with particles, and the aggravation of cake layer formation with thinner and denser cake layer. Additionally, inorganic components, especially Si and Al, in PMW accumulated into cake layer and strengthened the cake layer structure, inducing severer biofouling. However, SMW promoted bacterial metabolism during cake layer formation, thus aggravated the accumulation of organic components into cake layer. Therefore, SMW highlighted the organic components in cake layer, but weakened the inorganic functions in practical MBR operation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Flexible single-layer ionic organic-inorganic frameworks towards precise nano-size separation

    NASA Astrophysics Data System (ADS)

    Yue, Liang; Wang, Shan; Zhou, Ding; Zhang, Hao; Li, Bao; Wu, Lixin

    2016-02-01

    Consecutive two-dimensional frameworks comprised of molecular or cluster building blocks in large area represent ideal candidates for membranes sieving molecules and nano-objects, but challenges still remain in methodology and practical preparation. Here we exploit a new strategy to build soft single-layer ionic organic-inorganic frameworks via electrostatic interaction without preferential binding direction in water. Upon consideration of steric effect and additional interaction, polyanionic clusters as connection nodes and cationic pseudorotaxanes acting as bridging monomers connect with each other to form a single-layer ionic self-assembled framework with 1.4 nm layer thickness. Such soft supramolecular polymer frameworks possess uniform and adjustable ortho-tetragonal nanoporous structure in pore size of 3.4-4.1 nm and exhibit greatly convenient solution processability. The stable membranes maintaining uniform porous structure demonstrate precisely size-selective separation of semiconductor quantum dots within 0.1 nm of accuracy and may hold promise for practical applications in selective transport, molecular separation and dialysis systems.

  5. Preparation of Cu2O nanowire-blended polysulfone ultrafiltration membrane with improved stability and antimicrobial activity

    NASA Astrophysics Data System (ADS)

    Xu, Zehai; Ye, Shuaiju; Fan, Zheng; Ren, Fanghua; Gao, Congjie; Li, Qingbiao; Li, Guoqing; Zhang, Guoliang

    2015-10-01

    Polysulfone (PSF) membranes have been widely applied in water and wastewater treatment, food-processing and biomedical fields. In this study, we report the preparation of modified PSF membranes by blending PSF with Cu2O nanowires (NWs) to improve their stability and antifouling activity. Synthesis of novel Cu2O NWs/PSF-blended ultrafiltration membrane was achieved via phase inversion method by dispersing one-dimensional Cu2O nanowires in PSF casting solutions. Various techniques such as XRD, SEM, TEM, and EDS were applied to characterize and investigate the properties of nanowires and membranes. The introduced Cu2O nanowires can firmly be restricted into micropores of PSF membranes, and therefore, they can effectively prevent the serious leaking problem of inorganic substances in separation process. The blended PSF membranes also provided enhanced antimicrobial activity and superior permeation property compared to pure PSF membrane. The overall work can not only provide a new way for preparation of novel blended membranes with multidimensional nanomaterials, but can also be beneficial to solve the annoying problem of biofouling.

  6. Bio-inorganic synthesis of ZnO powders using recombinant His-tagged ZnO binding peptide as a promoter.

    PubMed

    Song, Lei; Liu, Yingying; Zhang, Zhifang; Wang, Xi; Chen, Jinchun

    2010-10-01

    Inorganic-binding peptides termed as genetically engineered polypeptides for inorganics (GEPIs), are small peptide sequences selected via combinatorial biology-based protocols of phage or cell surface display technologies. Recent advances in nanotechnology and molecular biology allow the engineering of these peptides with specific affinity to inorganics, often used as molecular linkers or assemblers, to facilitate materials synthesis, which provides a new insight into the material science and engineering field. As a case study on this biomimetic application, here we report a novel biosynthetic ZnO binding protein and its application in promoting bio-inorganic materials synthesis. In brief, the gene encoding a ZnO binding peptide(ZBP) was genetically fused with His(6)-tag and GST-tag using E.coli expression vector pET-28a (+) and pGEX-4T-3. The recombinant protein GST-His-ZBP was expressed, purified with Ni-NTA system, identified by SDS-PAGE electrophoresis and Western blot analysis and confirmed by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) analysis. Affinity adsorption test demonstrated that the fusion protein had a specific avidity for ZnO nanoparticles (NPs). Results from the bio-inorganic synthesis experiment indicated that the new protein played a promoting part in grain refinement and accelerated precipitation during the formation of the ultra-fine precursor powders in the Zn(OH)(2) sol. X-ray diffraction (XRD) analysis on the final products after calcining the precursor powders showed that hexagonal wurtzite ZnO crystals were obtained. Our work suggested a novel approach to the application about the organic-inorganic interactions.

  7. Comparison of dialysis membrane diffusion samplers and two purging methods in bedrock wells

    USGS Publications Warehouse

    Imbrigiotta, T.E.; Ehlke, T.A.; Lacombe, P.J.; Dale, J.M.; ,

    2002-01-01

    Collection of ground-water samples from bedrock wells using low-flow purging techniques is problematic because of the random spacing, variable hydraulic conductivity, and variable contamination of contributing fractures in each well's open interval. To test alternatives to this purging method, a field comparison of three ground-water-sampling techniques was conducted on wells in fractured bedrock at a site contaminated primarily with volatile organic compounds. Constituent concentrations in samples collected with a diffusion sampler constructed from dialysis membrane material were compared to those in samples collected from the same wells with a standard low-flow purging technique and a hybrid (high-flow/low-flow) purging technique. Concentrations of trichloroethene, cis-1,2-dichloroethene, vinyl chloride, calcium, chloride, and alkalinity agreed well among samples collected with all three techniques in 9 of the 10 wells tested. Iron concentrations varied more than those of the other parameters, but their pattern of variation was not consistent. Overall, the results of nonparametric analysis of variance testing on the nine wells sampled twice showed no statistically significant difference at the 95-percent confidence level among the concentrations of volatile organic compounds or inorganic constituents recovered by use of any of the three sampling techniques.

  8. Organic/Inorganic Polymeric Composites for Heat-Transfer Reduction

    NASA Technical Reports Server (NTRS)

    Smith, Trent; Williams, Martha

    2008-01-01

    Organic/inorganic polymeric composite materials have been invented with significant reduction in heat-transfer properties. Measured decreases of 20-50 percent in thermal conductivity versus that of the unmodified polymer matrix have been attained. These novel composite materials also maintain mechanical properties of the unmodified polymer matrix. The present embodiments are applicable, but not limited to: racing applications, aerospace applications, textile industry, electronic applications, military hardware improvements, and even food service industries. One specific application of the polymeric composition is for use in tanks, pipes, valves, structural supports, and components for hot or cold fluid process systems where heat flow through materials is problematic and not desired. With respect to thermal conductivity and physical properties, these materials are superior alternatives to prior composite materials. These materials may prove useful as substitutes for metals in some cryogenic applications. A material of this type can be made from a blend of thermoplastics, elastomers, and appropriate additives and processed on normal polymer processing equipment. The resulting processed organic/inorganic composite can be made into fibers, molded, or otherwise processed into useable articles.

  9. In Situ Synthesis of Metal Nanoparticle Embedded Hybrid Soft Nanomaterials.

    PubMed

    Divya, Kizhmuri P; Miroshnikov, Mikhail; Dutta, Debjit; Vemula, Praveen Kumar; Ajayan, Pulickel M; John, George

    2016-09-20

    The allure of integrating the tunable properties of soft nanomaterials with the unique optical and electronic properties of metal nanoparticles has led to the development of organic-inorganic hybrid nanomaterials. A promising method for the synthesis of such organic-inorganic hybrid nanomaterials is afforded by the in situ generation of metal nanoparticles within a host organic template. Due to their tunable surface morphology and porosity, soft organic materials such as gels, liquid crystals, and polymers that are derived from various synthetic or natural compounds can act as templates for the synthesis of metal nanoparticles of different shapes and sizes. This method provides stabilization to the metal nanoparticles by the organic soft material and advantageously precludes the use of external reducing or capping agents in many instances. In this Account, we exemplify the green chemistry approach for synthesizing these materials, both in the choice of gelators as soft material frameworks and in the reduction mechanisms that generate the metal nanoparticles. Established herein is the core design principle centered on conceiving multifaceted amphiphilic soft materials that possess the ability to self-assemble and reduce metal ions into nanoparticles. Furthermore, these soft materials stabilize the in situ generated metal nanoparticles and retain their self-assembly ability to generate metal nanoparticle embedded homogeneous organic-inorganic hybrid materials. We discuss a remarkable example of vegetable-based drying oils as host templates for metal ions, resulting in the synthesis of novel hybrid nanomaterials. The synthesis of metal nanoparticles via polymers and self-assembled materials fabricated via cardanol (a bioorganic monomer derived from cashew nut shell liquid) are also explored in this Account. The organic-inorganic hybrid structures were characterized by several techniques such as UV-visible spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Utilization of silver nanoparticle-based hybrid nanomaterials as an antimicrobial material is another illustration of the advantage of hybrid nanomaterials. We envision that the results summarized in this Account will help the scientific community to design and develop diverse organic-inorganic hybrid materials using environmentally benign methods and that these materials will yield advanced properties that have multifaceted applications in various research fields.

  10. Recovery of Rare Earths, Precious Metals and Other Critical Materials from Geothermal Waters with Advanced Sorbent Structures

    DOE Data Explorer

    Pamela M. Kinsey

    2015-09-30

    The work evaluates, develops and demonstrates flexible, scalable mineral extraction technology for geothermal brines based upon solid phase sorbent materials with a specific focus upon rare earth elements (REEs). The selected organic and inorganic sorbent materials demonstrated high performance for collection of trace REEs, precious and valuable metals. The nanostructured materials typically performed better than commercially available sorbents. Data contains organic and inorganic sorbent removal efficiency, Sharkey Hot Springs (Idaho) water chemsitry analysis, and rare earth removal efficiency from select sorbents.

  11. Luminescent hybrid materials based on (8-hydroxyquinoline)-substituted metal-organic complexes and lead-borate glasses

    NASA Astrophysics Data System (ADS)

    Petrova, Olga B.; Anurova, Maria O.; Akkuzina, Alina A.; Saifutyarov, Rasim R.; Ermolaeva, Ekaterina V.; Avetisov, Roman I.; Khomyakov, Andrew V.; Taydakov, Ilya V.; Avetissov, Igor Ch.

    2017-07-01

    Novel luminescent organic-inorganic hybrid materials based on 8-hydroxyquinoline metal complexes (Liq, Kq, Naq, Rbq, Mgq2, Srq2, Znq2, Scq3, Alq3, Gaq3, and Inq3) have been synthesized by a high temperature exchange reaction with 80PbF2-20B2O3 inorganic low-melting glass. The mechanical and optical properties, transmission spectra, emission an excitation photoluminescence, and luminescence kinetic of hybrid materials were studied. All hybrid materials showed a wide luminescence band in the range 400-700 nm.

  12. Inorganic nanotubes and fullerene-like materials.

    PubMed

    Tenne, Reshef

    2002-12-02

    Following the discovery of fullerenes and carbon nanotubes, it was shown that nanoparticles of inorganic layered compounds, like MoS2, are unstable in the planar form and they form closed cage structures with polyhedral or nanotubular shapes. Various issues on the structure, synthesis, and properties of such inorganic fullerene-like structures are reviewed, together with some possible applications.

  13. Polymer-Attached Functional Inorganic-Organic Hybrid Nano-Composite Aerogels

    DTIC Science & Technology

    2003-01-01

    drugs. The chemistry to synthesize polyamino- siloxane based aerogel composite was discussed. In addition, two approaches to synthesize PHEMA aerogel... Composite Aerogels DISTRIBUTION: Approved for public release, distribution unlimited This paper is part of the following report: TITLE: Materials...Proc. Vol. 740 © 2003 Materials Research Society 112.24 Polymer-Attached Functional Inorganic-Organic Hybrid Nano- composite Aerogels Xipeng Liu, Mingzhe

  14. Interfacial Effects and Organization of Inorganic-Organic Composite Solids.

    DTIC Science & Technology

    1998-05-20

    SITU NMR STUDY OF THE HYDROTHERMAL SYNTHESIS OF TEMPLATE-MEDIATED MICROPOROUS ALUMINOPHOSPHATE MATERIALS, Conne M Gersrdin, Pnnccton Univ, Dept...quantitatively characterize the hydrothermal medium while the synthesis proceeds can yield to a better description of the different steps of the...Inorganic-Organic Composite Solids," focused on recent applications in materials synthesis that use structure-directing agents and self-assembly

  15. Meeting Materials for the 4th NRC Meeting on the Guidance for and the Review of EPA's Toxicological Assessment of Inorganic Arsenic

    EPA Science Inventory

    On December 2-3, 2015, the National Research Council (NRC) hosted the 4th meeting of the committee formed to peer review the draft IRIS assessment of inorganic arsenic. EPA presented background and overview materials during the public session on December 2nd. This information co...

  16. Plankton Dynamics and Mesoscale Turbulence

    DTIC Science & Technology

    2010-06-29

    transformation of inorganic materials and light into living matter by photosynthesis ) is operated mainly by small, unicellular algae that float freely in the...ecosystems, primary production (the transformation of inorganic materials and light into living matter by photosynthesis ) is operated mainly by small...them into biomass via photosynthesis . The main limiting factors for phytoplankton growth are light and nutrient availability; for this reason

  17. A review on the application of inorganic nano-structured materials in the modification of textiles: focus on anti-microbial properties.

    PubMed

    Dastjerdi, Roya; Montazer, Majid

    2010-08-01

    Textiles can provide a suitable substrate to grow micro-organisms especially at appropriate humidity and temperature in contact to human body. Recently, increasing public concern about hygiene has been driving many investigations for anti-microbial modification of textiles. However, using many anti-microbial agents has been avoided because of their possible harmful or toxic effects. Application of inorganic nano-particles and their nano-composites would be a good alternative. This review paper has focused on the properties and applications of inorganic nano-structured materials with good anti-microbial activity potential for textile modification. The discussed nano-structured anti-microbial agents include TiO(2) nano-particles, metallic and non-metallic TiO(2) nano-composites, titania nanotubes (TNTs), silver nano-particles, silver-based nano-structured materials, gold nano-particles, zinc oxide nano-particles and nano-rods, copper nano-particles, carbon nanotubes (CNTs), nano-clay and its modified forms, gallium, liposomes loaded nano-particles, metallic and inorganic dendrimers nano-composite, nano-capsules and cyclodextrins containing nano-particles. This review is also concerned with the application methods for the modification of textiles using nano-structured materials. Copyright 2010 Elsevier B.V. All rights reserved.

  18. Inorganic particle analysis of dental impression elastomers.

    PubMed

    Carlo, Hugo Lemes; Fonseca, Rodrigo Borges; Soares, Carlos José; Correr, Américo Bortolazzo; Correr-Sobrinho, Lourenço; Sinhoreti, Mário Alexandre Coelho

    2010-01-01

    The aim of this study was to determine quantitatively and qualitatively the inorganic particle fraction of commercially available dental elastomers. The inorganic volumetric fraction of two addition silicones (Reprosil Putty/Fluid and Flexitime Easy Putty/Fluid), three condensation silicones (Clonage Putty/Fluid, Optosil Confort/Xantopren VL and Silon APS Putty/Fluid), one polyether (Impregum Soft Light Body) and one polysulfide (Permlastic Light Body) was accessed by weighing a previously determined mass of each material in water before and after burning samples at 600 ºC, during 3 h. Unsettled material samples were soaked in acetone and chloroform for removal of the organic portion. The remaining filler particles were sputter-coated with gold evaluation of their morphology and size, under scanning electron microscopy (SEM). Flexitime Easy Putty was the material with the highest results for volumetric particle fraction, while Impregum Soft had the lowest values. Silon 2 APS Fluid presented the lowest mean filler size values, while Clonage Putty had the highest values. SEM micrographs of the inorganic particles showed several morphologies - lathe-cut, spherical, spherical-like, sticks, and sticks mixed to lathe-cut powder. The results of this study revealed differences in particle characteristics among the elastometic materials that could lead to different results when testing mechanical properties.

  19. [Correlation analysis and evaluation of inorganic elements in Angelica sinensis and its correspondence soil from different regions].

    PubMed

    Yan, Hui; Duan, Jin-ao; Qian, Da-wei; Su, Shu-lan; Song, Bing-sheng; He, Zi-qing

    2011-04-01

    Evaluate the relationship between the inorganic elements and the genuineness, invigoration efficacy of this medicinal material by qualitative and quantitative analysis of the inorganic elements in Angelica sinensis and its correspondence soil. The contents of 14 kinds of inorganic elements from 40 samples from 4 main habits of Angelica sinensis in China were determined by the method of ICP-AES. In Angelica sinensis and its correspondence soil, significant positive correlations existed between each pair of Ca, Na, Ni. The enrichment coefficients of Mg by Angelica sinensis was a certain peculiarity. The analysis showed that Zn, Cu, Mn, Mg were distincter to Angelica sinensis's geo-authentic than other elements. The results seemly confirmed that the Mingui was considered as geo-authentic crude drugs by traditional knowledge. The inorganic elements in Angelica sinensis may be correlated with its geo-authentic certainly. This result can provide scientific basis for understanding of Angelica sinensis's geo-authentic nature and the active material base.

  20. THE PHYSICAL AND CHEMICAL MICROSTRUCTURE OF THE ACHATINA FULICA EPIPHRAGM.

    PubMed

    Struthers, M.; Rosair, G.; Buckman, J.; Viney, C.

    2002-05-01

    Microstructural characterization of Achatina fulica Bowdich, 1822 epiphragms and mucus secretions was performed to address two questions: what are the structure and composition of the reinforcing inorganic phase in the epiphragms, and what enables a durable epiphragm to form quickly in comparison to other biomineralized materials? Characterization was performed by a combination of light microscopy (relying on a variety of contrast modes), wet chemical tests, environmental scanning electron microscopy (including the use of energy dispersive X-ray analysis to obtain compositional data), and X-ray diffraction. The morphology of the inorganic phase promotes mechanical interlocking and presents a large surface for binding to the organic matrix. Strong binding occurs between the organic and inorganic phases. The inorganic phase adopts the calcite structure; its composition is Ca(0.912) Mg(0.088) CO(3). Epiphragms can form quickly because pre-grown crystals of the inorganic reinforcing phase are co-deposited with the mucus matrix. Unlike other biomineralized material, the crystals are not solution-grown in situ on an organic template in the final product.

  1. Electrochemical determination of inorganic mercury and arsenic--A review.

    PubMed

    Zaib, Maria; Athar, Muhammad Makshoof; Saeed, Asma; Farooq, Umar

    2015-12-15

    Inorganic mercury and arsenic encompasses a term which includes As(III), As(V) and Hg(II) species. These metal ions have been extensively studied due to their toxicity related issues. Different analytical methods are used to monitor inorganic mercury and arsenic in a variety of samples at trace level. The present study reviews various analytical techniques available for detection of inorganic mercury and arsenic with particular emphasis on electrochemical methods especially stripping voltammetry. A detailed critical evaluation of methods, advantages of electrochemical methods over other analytical methods, and various electrode materials available for mercury and arsenic analysis is presented in this review study. Modified carbon paste electrode provides better determination due to better deposition with linear and improved response under studied set of conditions. Biological materials may be the potent and economical alternative as compared to macro-electrodes and chemically modified carbon paste electrodes in stripping analysis of inorganic mercury and arsenic. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. 3D printing of shape-conformable thermoelectric materials using all-inorganic Bi2Te3-based inks

    NASA Astrophysics Data System (ADS)

    Kim, Fredrick; Kwon, Beomjin; Eom, Youngho; Lee, Ji Eun; Park, Sangmin; Jo, Seungki; Park, Sung Hoon; Kim, Bong-Seo; Im, Hye Jin; Lee, Min Ho; Min, Tae Sik; Kim, Kyung Tae; Chae, Han Gi; King, William P.; Son, Jae Sung

    2018-04-01

    Thermoelectric energy conversion offers a unique solution for generating electricity from waste heat. However, despite recent improvements in the efficiency of thermoelectric materials, the widespread application of thermoelectric generators has been hampered by challenges in fabricating thermoelectric materials with appropriate dimensions to perfectly fit heat sources. Herein, we report an extrusion-based three-dimensional printing method to produce thermoelectric materials with geometries suitable for heat sources. All-inorganic viscoelastic inks were synthesized using Sb2Te3 chalcogenidometallate ions as inorganic binders for Bi2Te3-based particles. Three-dimensional printed materials with various geometries showed homogenous thermoelectric properties, and their dimensionless figure-of-merit values of 0.9 (p-type) and 0.6 (n-type) were comparable to the bulk values. Conformal cylindrical thermoelectric generators made of 3D-printed half rings mounted on an alumina pipe were studied both experimentally and computationally. Simulations show that the power output of the conformal, shape-optimized generator is higher than that of conventional planar generators.

  3. Bioactive Nanocomposites for Tissue Repair and Regeneration: A Review

    PubMed Central

    Bramhill, Jane; Ross, Sukunya; Ross, Gareth

    2017-01-01

    This review presents scientific findings concerning the use of bioactive nanocomposites in the field of tissue repair and regeneration. Bioactivity is the ability of a material to incite a specific biological reaction, usually at the boundary of the material. Nanocomposites have been shown to be ideal bioactive materials due the many biological interfaces and structures operating at the nanoscale. This has resulted in many researchers investigating nanocomposites for use in bioapplications. Nanocomposites encompass a number of different structures, incorporating organic-inorganic, inorganic-inorganic and bioinorganic nanomaterials and based upon ceramic, metallic or polymeric materials. This enables a wide range of properties to be incorporated into nanocomposite materials, such as magnetic properties, MR imaging contrast or drug delivery, and even a combination of these properties. Much of the classical research was focused on bone regeneration, however, recent advances have enabled further use in soft tissue body sites too. Despite recent technological advances, more research is needed to further understand the long-term biocompatibility impact of the use of nanoparticles within the human body. PMID:28085054

  4. Styrene process condensate treatment with a combination process of UF and NF for reuse.

    PubMed

    Wang, Aijun; Liu, Guangmin; Huang, Jin; Wang, Lijuan; Li, Guangbin; Su, Xudong; Qi, Hong

    2013-01-15

    Aiming at reusing the SPC to save water resource and heat energy, a combination treatment process of UF/NF was applied to remove inorganic irons, suspended particles and little amount of organic contaminants in this article. To achieve the indexes of CODM≤5.00 mg L(-1), oil≤2.00 mg L(-1), conductivity≤10.00 μs cm(-1), pH of 6.0-8.0, the NF membrane process was adopted. It was necessary to employ a pretreatment process to reduce NF membrane fouling. Hence UF membrane as an efficient pretreatment unit was proposed to remove the inorganic particles, such as iron oxide catalyst, to meet the influent demands of NF. The effluent of UF, which was less than 0.02 mg L(-1) of total iron, went into a security filter and then was pumped into the NF process unit. High removal efficiencies of CODM, oil and conductivity were achieved by using NF process. The ABS grafting copolymerization experiment showed that the effluent of the combination process met the criteria of ABS production process, meanwhile the process could alleviate the environment pollution. It was shown that this combination process concept was feasible and successful in treating the SPC. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Effects of inorganic phosphate on the light dependent thylakoid energization of intact spinach chloroplasts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Heineke, D.; Heldt, H.W.; Stitt, M.

    1989-09-01

    The light dependent energization of the thylakoid membrane was analyzed in isolated intact spinach (Spinacia oleracea L.) chloroplasts incubated with different concentrations of inorganic phosphate (Pi). Two independent methods were used: (a) the accumulation of ({sup 14}C)5,5-dimethyl-2,4-oxazolidinedione and ({sup 14}C)methylamine; (b) the energy dependent chlorophyll fluorescence quenching. The inhibition of CO{sub 2} fixation by superoptimal medium Pi or by adding glyceraldehyde - an inhibitor of the Calvin cycle - leads to an increased energization of the thylakoid membrane; however, the membrane energization decreases when chloroplasts are inhibited by suboptimal Pi. This specific low phosphate effect could be partially reversed bymore » adding oxaloacetate, which regenerates the electron acceptor NADP{sup +} and stimulates linear electron transport. The energization seen in low Pi is, however, always lower than in superoptimal Pi, even in the presence of oxaloacetate. Energization recovers in the presence of low amounts of N,N{prime}-dicyclohexylcarbodiimide, which reacts with proton channels including the coupling factor 1 ATP synthase. N,N{prime}-Dicyclohexylcarbodiimide has no effect on energization of chloroplasts in superoptimal Pi. These results suggest there is a specific low phosphate proton leak in the thylakoids, and its origin is discussed.« less

  6. Crystal engineering, structure–function relationships, and the future of metal–organic frameworks

    DOE PAGES

    Allendorf, Mark D.; Stavila, Vitalie

    2014-10-15

    Metal-Organic Frameworks (MOFs) are a rapidly expanding class of hybrid organic-inorganic materials that can be rationally designed and assembled through crystal engineering. The explosion of interest in this subclass of coordination polymers results from their outstanding properties and myriad possible applications that include traditional uses of microporous materials, such as gas storage, separations, and catalysis, to new realms in biomedicine, electronic devices, and and information storage. The objective of this Highlight article is to provide the reader with a sense of where the field stands after roughly fifteen years of research. Remarkable progress has been made, but the barriers tomore » practical and commercial advances are also illuminated. We discuss the basic elements of MOF assembly and present a conceptual hierarchy of structural elements that assists in understanding how unique properties in these materials can be achieved. Structure-function relationships are then discussed; several are now well understood as a result of the focused efforts of many research groups over the past decade. Prospects for practical applications of MOFs in membranes, catalysis, biomedicine, and as active components in electronic and photonic devices are also discussed. Finally, we list key challenges that, in our view, must be addressed for these materials to realize their full potential in the marketplace.« less

  7. Holographic patterning of organic-inorganic photopolymerizable nanocomposites

    NASA Astrophysics Data System (ADS)

    Sakhno, Oksana V.; Goldenberg, Leonid M.; Smirnova, Tatiana N.; Stumpe, J.

    2009-09-01

    We present here novel easily processible organic-inorganic nanocomposites suitable for holographic fabrication of diffraction optical elements (DOE). The nanocomposites are based on photocurable acrylate monomers and inorganic nanoparticles (NP). The compatibility of inorganic NP with monomers was achieved by capping the NP surface with proper organic shells. Surface modification allows to introduce up to 50wt.% of inorganic NP in organic media. Depending on the NP nature (metal oxides, phosphates, semiconductors, noble metals) and their properties, the materials for both efficient DOE and multifunctional elements can be designed. Organic-inorganic composites prepared have been successfully used for the effective inscription of periodic volume refractive index structures using the holographic photopolymerization method. The nanocomposite preparation procedure, their properties and optical performance of holographic gratings are reported. The use of functional NP makes it possible to obtain effective holographic gratings having additional physical properties such as light-emission or NLO. Some examples of such functional polymer-NP structures and their possible application fields are presented. The combination of easy photo-patterning of soft organic compounds with physical properties of inorganic materials in new nanocomposites and the flexibility of the holographic patterning method allow the fabrication of mono- and multifunctional one- and multi-dimensional passive or active optical and photonic elements.

  8. Zwitterionic materials for antifouling membrane surface construction.

    PubMed

    He, Mingrui; Gao, Kang; Zhou, Linjie; Jiao, Zhiwei; Wu, Mengyuan; Cao, Jialin; You, Xinda; Cai, Ziyi; Su, Yanlei; Jiang, Zhongyi

    2016-08-01

    Membrane separation processes are often perplexed by severe and ubiquitous membrane fouling. Zwitterionic materials, keeping electric neutrality with equivalent positive and negative charged groups, are well known for their superior antifouling properties and have been broadly utilized to construct antifouling surfaces for medical devices, biosensors and marine coatings applications. In recent years, zwitterionic materials have been more and more frequently utilized for constructing antifouling membrane surfaces. In this review, the antifouling mechanisms of zwitterionic materials as well as their biomimetic prototypes in cell membranes will be discussed, followed by the survey of common approaches to incorporate zwitterionic materials onto membrane surfaces including surface grafting, surface segregation, biomimetic adhesion, surface coating and so on. The potential applications of these antifouling membranes are also embedded. Finally, we will present a brief perspective on the future development of zwitterionic materials modified antifouling membranes. Membrane fouling is a severe problem hampering the application of membrane separation technology. The properties of membrane surfaces play a critical role in membrane fouling and antifouling behavior/performance. Antifouling membrane surface construction has evolved as a hot research issue for the development of membrane processes. Zwitterionic modification of membrane surfaces has been recognized as an effective strategy to resist membrane fouling. This review summarizes the antifouling mechanisms of zwitterionic materials inspired by cell membranes as well as the popular approaches to incorporate them onto membrane surfaces. It can help form a comprehensive knowledge about the principles and methods of modifying membrane surfaces with zwitterionic materials. Finally, we propose the possible future research directions of zwitterionic materials modified antifouling membranes. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  9. Portable spotter for fluorescent contaminants on surfaces

    DOEpatents

    Schuresko, Daniel D.

    1980-01-01

    A portable fluorescence-based spotter for polynuclear aromatic hydrocarbon contamination on personnel and work area surfaces under ambient lighting conditions is provided. This instrument employs beam modulation and phase sensitive detection for discriminating between fluorescence from organic materials from reflected background light and inorganic fluorescent material. The device uses excitation and emission filters to provide differentiation between classes of aromatic organic compounds. Certain inorganic fluorescent materials, including heavy metal compounds, may also be distinguished from the organic compounds, despite both having similar optical properties.

  10. Cryogenic Properties of Inorganic Insulation Materials for ITER Magnets: A Review

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Simon, N.J.

    1994-12-01

    Results of a literature search on the cryogenic properties of candidate inorganic insulators for the ITER TF magnets are reported. The materials investigated include: Al{sub 2}O{sub 3}, AlN, MgO, porcelain, SiO{sub 2}, MgAl{sub 2}O{sub 4}, ZrO{sub 2}, and mica. A graphical presentation is given of mechanical, elastic, electrical, and thermal properties between 4 and 300 K. A companion report reviews the low temperature irradiation resistance of these materials.

  11. [Study on spectroscopic characterization and property of PES/ micro-nano cellulose composite membrane material].

    PubMed

    Tang, Huan-Wei; Zhang, Li-Ping; Li, Shuai; Zhao, Guang-Jie; Qin, Zhu; Sun, Su-Qin

    2010-03-01

    In the present paper, the functional groups of PES/micro-nano cellulose composite membrane materials were characterized by Fourier transform infrared spectroscopy (FTIR). Also, changes in crystallinity in composite membrane materials were analyzed using X-ray diffraction (XRD). The effects of micro-nano cellulose content on hydrophilic property of composite membrane material were studied by measuring hydrophilic angle. The images of support layer structure of pure PES membrane material and composite membrane material were showed with scanning electron microscope (SEM). These results indicated that in the infrared spectrogram, the composite membrane material had characteristic peaks of both PES and micro-nano cellulose without appearance of other new characteristics peaks. It revealed that there were no new functional groups in the composite membrane material, and the level of molecular compatibility was achieved, which was based on the existence of inter-molecular hydrogen bond association between PES and micro-nano cellulose. Due to the existence of micro-nano cellulose, the crystallinity of composite membrane material was increased from 37.7% to 47.9%. The more the increase in micro-nano cellulose mass fraction, the better the van de Waal force and hydrogen bond force between composite membrane material and water were enhanced. The hydrophilic angle of composite membrane material was decreased from 55.8 degrees to 45.8 degrees and the surface energy was raised from 113.7 to 123.5 mN x m(-2). Consequently, the hydrophilic property of composite membrane material was improved. The number of pores in the support layer of composite membrane material was lager than that of pure PES membrane. Apparently, pores were more uniformly distributed.

  12. Membrane-based energy efficient dewatering of microalgae in biofuels production and recovery of value added co-products.

    PubMed

    Bhave, Ramesh; Kuritz, Tanya; Powell, Lawrence; Adcock, Dale

    2012-05-15

    The objective of this paper is to describe the use of membranes for energy efficient biomass harvesting and dewatering. The dewatering of Nannochloropsis sp. was evaluated with polymeric hollow fiber and tubular inorganic membranes to demonstrate the capabilities of a membrane-based system to achieve microalgal biomass of >150 g/L (dry wt.) and ∼99% volume reduction through dewatering. The particle free filtrate containing the growth media is suitable for recycle and reuse. For cost-effective processing, hollow fiber membranes can be utilized to recover 90-95% media for recycle. Tubular membranes can provide additional media and water recovery to achieve target final concentrations. Based on the operating conditions used in this study and taking into scale-up considerations, an integrated hollow fiber-tubular membrane system can process microalgal biomass with at least 80% lower energy requirement compared to traditional processes. Backpulsing was found to be an effective flux maintenance strategy to minimize flux decline at high biomass concentration. An effective chemical cleaning protocol was developed for regeneration of fouled membranes.

  13. Surface functionalization of metal organic frameworks for mixed matrix membranes

    DOEpatents

    Albenze, Erik; Lartey, Michael; Li, Tao; Luebke, David R.; Nulwala, Hunaid B.; Rosi, Nathaniel L.; Venna, Surendar R.

    2017-03-21

    Mixed Matrix Membrane (MMM) are composite membranes for gas separation and comprising a quantity of inorganic filler particles, in particular metal organic framework (MOF), dispersed throughout a polymer matrix comprising one or more polymers. This disclosure is directed to MOF functionalized through addition of a pendant functional group to the MOF, in order to improve interaction with a surrounding polymer matrix in a MMM. The improved interaction aids in avoiding defects in the MMM due to incompatible interfaces between the polymer matrix and the MOF particle, in turn increasing the mechanical and gas separation properties of the MMM. The disclosure is also directed to a MMM incorporating the surface functionalized MOF.

  14. The use of multiple endpoints to assess cellular responses to environmental contaminants in the interstitial marine ciliate Euplotes crassus.

    PubMed

    Gomiero, A; Sforzini, S; Dagnino, A; Nasci, C; Viarengo, A

    2012-06-15

    This paper presents the results of investigations on the suitability of Euplotes crassus, an interstitial marine ciliate, to be used as model organism in ecotoxicology and thereafter to evaluate the toxicity of estuarine and coastal sediments upon laboratory exposure. Nowadays, anthropogenic activities have resulted in accumulation of metals and organic pollutants in the environment as well as in the food chain hence leading to serious ecological and human health problems. This may pose a risk to benthic and epibenthic organisms and it is crucial to discover toxicity tests that will identify adverse effects of sediment-associated chemicals on benthic organisms. Due to their nature as a eukaryotic cell/organism and their position in the food web, ciliated protozoa are suitable models for evaluating the effects of pollution on aquatic communities. Lethal and sublethal effects of exposure to inorganic and organic pollutants were tested on the cell mortality, replication rate, lysosomal membrane stability and endocytosis rate of E. crassus. Increasing nominal concentrations of individual and mixtures of mercury, copper, and benzo(a)pyrene were investigated in this study as they might be bioavailable in naturally occurring polluted sites. A significant decrease in the mean replication rate (p<0.05) was found after 24h exposures to m/μM concentrations of all tested pollutants. At the same time, significant decreases of lysosomal membrane stability (p<0.05) were observed for Cu (5 μM), Hg (10 nM), and B(a)P (200 nM). Among the entire suite of tests, endocytosis rate test demonstrated the highest sensitivity. Exposures to binary mixtures of all studied pollutants were performed showing both inorganic-organic and inorganic-inorganic additive and/or antagonist effects. Moreover, medium salinity was also varied to mimic estuarine-like environmental conditions linking biological response to ionic strengths. Under these conditions significant increases of both endocytosis rate and lysosomal membrane stability were observed and related to the increment of some Hg- and Cu-related toxic complexes. The studied biomarkers were always able to discriminate between the effects of organic and inorganic pollutants. Together with the short time and simplicity of the test procedures, results obtained in this study indicate that E. crassus is a promising and convenient bioindicator for evaluating the toxicity of different environmental matrixes like pore water, sediments and wastewaters--polluted by metals and organic pollutants. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Recent advances in magnetic resonance microscopy to the physical structure characterization of carbonaceous and inorganic materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gregory, D.M.; Gerald, R.E.; Cody, G.D.

    1997-04-01

    Magnetic resonance microscopy (MRM) techniques have been employed to study the molecular architectures and properties of structural polymers, fossil fuels, microporous carbons and inorganic catalysts.

  16. Inorganic and methane clathrates: Versatility of guest–host compounds for energy harvesting

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krishna, Lakshmi; Koh, Carolyn A.

    ABSTRACT This review article evaluates the structure–property relations of inorganic clathrates and clathrate hydrates and their potential role in energy harvesting. There is potential cross-fertilization between the two research areas. Guest–host clathrate compounds exhibit unique structural and physical properties, which lead to their versatile roles in energy applications. Prominent classes of clathrate compounds are gas hydrates and inorganic clathrates. That said, there is limited cross-fertilization between the clathrate hydrate and inorganic clathrate communities, with researchers in the respective fields being less informed on the other field. Yet the structures and unique guest–host interactions in both these compounds are common importantmore » features of these clathrates. Common features and procedures can inspire and inform development between the compound classes, which may be important to the technological advancements for the different clathrate materials, e.g., structure characterization techniques and guest–host dynamics in which the “guest” tends to be imprisoned in the host structure, until external forces are applied. Conversely, the diversity in chemical compositions of these two classes of materials leads to the different applications from methane capture and storage to converting waste heat to electricity (thermoelectrics). This article highlights the structural and physical similarities and differences of inorganic and methane clathrates. The most promising state-of-the-art applications of the clathrates are highlighted for harvesting energy from methane (clathrate) hydrate deposits under the ocean and for inorganic clathrates as promising thermoelectric materials.« less

  17. Inorganic and methane clathrates: Versatility of guest–host compounds for energy harvesting

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krishna, Lakshmi; Koh, Carolyn A.

    2015-01-01

    ABSTRACT This review article evaluates the structure–property relations of inorganic clathrates and clathrate hydrates and their potential role in energy harvesting. There is potential cross-fertilization between the two research areas. Guest–host clathrate compounds exhibit unique structural and physical properties, which lead to their versatile roles in energy applications. Prominent classes of clathrate compounds are gas hydrates and inorganic clathrates. That said, there is limited cross-fertilization between the clathrate hydrate and inorganic clathrate communities, with researchers in the respective fields being less informed on the other field. Yet the structures and unique guest–host interactions in both these compounds are common importantmore » features of these clathrates. Common features and procedures can inspire and inform development between the compound classes, which may be important to the technological advancements for the different clathrate materials, e.g., structure characterization techniques and guest–host dynamics in which the “guest” tends to be imprisoned in the host structure, until external forces are applied. Conversely, the diversity in chemical compositions of these two classes of materials leads to the different applications from methane capture and storage to converting waste heat to electricity (thermoelectrics). This article highlights the structural and physical similarities and differences of inorganic and methane clathrates. The most promising state-of-the-art applications of the clathrates are highlighted for harvesting energy from methane (clathrate) hydrate deposits under the ocean and for inorganic clathrates as promising thermoelectric materials.« less

  18. Mixing Halogens To Assemble an All-Inorganic Layered Perovskite with Warm White-Light Emission.

    PubMed

    Li, Xianfeng; Wang, Sasa; Zhao, Sangen; Li, Lina; Li, Yanqiang; Zhao, Bingqing; Shen, Yaoguo; Wu, Zhenyue; Shan, Pai; Luo, Junhua

    2018-05-01

    Most of single-component white-light-emitting materials focus on organic-inorganic hybrid perovskites, metal-organic frameworks, as well as all-inorganic semiconductors. In this work, we successfully assembled an all-inorganic layered perovskite by mixing two halogens of distinct ionic radii, namely, Rb 2 CdCl 2 I 2 , which emits "warm" white light with a high color rendering index of 88. To date, Rb 2 CdCl 2 I 2 is the first single-component white-light-emitting material with an all-inorganic layered perovskite structure. Furthermore, Rb 2 CdCl 2 I 2 is thermally highly stable up to 575 K. A series of luminescence measurements show that the white-light emission arises from the lattice deformation, which are closely related to the [CdCl 4 I 2 ] 2- octahedra with high distortion from the distinct ionic radii of Cl and I. The first-principles calculations reveal that both the Cl and I components make significant contributions to the electronic band structures of Rb 2 CdCl 2 I 2 . These findings indicate that mixing halogens is an effective route to design and synthesize new single-component white-light-emitting materials. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Development of organic-inorganic double hole-transporting material for high performance perovskite solar cells

    NASA Astrophysics Data System (ADS)

    Jo, Jea Woong; Seo, Myung-Seok; Jung, Jae Woong; Park, Joon-Suh; Sohn, Byeong-Hyeok; Ko, Min Jae; Son, Hae Jung

    2018-02-01

    The control of the optoelectronic properties of the interlayers of perovskite solar cells (PSCs) is crucial for achieving high photovoltaic performances. Of the solution-processable interlayer candidates, NiOx is considered one of the best inorganic hole-transporting layer (HTL) materials. However, the power conversion efficiencies (PCEs) of NiOx-based PSCs are limited by the unfavorable contact between perovskite layers and NiOx HTLs, the high density of surface trap sites, and the inefficient charge extraction from perovskite photoactive layers to anodes. Here, we introduce a new organic-inorganic double HTL consisting of a Cu:NiOx thin film passivated by a conjugated polyelectrolyte (PhNa-1T) film. This double HTL has a significantly lower pinhole density and forms better contact with perovskite films, which results in enhanced charge extraction. As a result, the PCEs of PSCs fabricated with the double HTL are impressively improved up to 17.0%, which is more than 25% higher than that of the corresponding PSC with a Cu:NiOx HTL. Moreover, PSCs with the double HTLs exhibit similar stabilities under ambient conditions to devices using inorganic Cu:NiOx. Therefore, this organic-inorganic double HTL is a promising interlayer material for high performance PSCs with high air stability.

  20. Assessment of bone repair in critical-size defect in the calvarium of rats after the implantation of tricalcium phosphate beta (β-TCP).

    PubMed

    de Freitas Silva, Leonardo; de Carvalho Reis, Erik Neiva Ribeiro; Barbara, Tânia Aparecida; Bonardi, João Paulo; Garcia, Idelmo Rangel; de Carvalho, Paulo Sérgio Perri; Ponzoni, Daniela

    2017-07-01

    Evaluating the osteoconductive property of tricalcium phosphate beta (β-TCP) in comparison to that of inorganic bovine bone for repair in a critical-size defect in the rat calvarium. Critical-size defects of 7mm were made with a trephine in the calvaria of 48 Wistar rats. The animals were divided into four groups, and the defects in each group were filled with tricalcium phosphate beta (β-TCP), inorganic bovine bone (Bio-Oss), autogenous bone, or left empty. The animals were euthanized at two different time points (30 and 60days post-operation). All defects were recovered with a absorbable membrane of bovine cortical bone. Histological, histometric, and immunohistochemical (osteocalcin) assessments were carried out at 30 and 60days post-operation. At 30days post-operation, all groups showed areas of bone formation, predominantly when autogenous grafts were used. However, there were no statistically significant differences between the treatment groups (p>0.05). After 60days, there were similarities in the bone formation patterns between the β-TCP (26.32±) and Bio-Oss (17.35±) groups (p=0.549). In terms of the immunohistochemical assessment of osteocalcin, the clot group showed light to moderate staining at 30 and 60days. The autogenous group showed moderate staining at 30days and moderate to intense staining after 60days. The Bio-Oss group showed light to moderate staining after 30days and intense staining at 60days. The β-TCP group showed moderate staining at 30 and 60days post-operation. β-TCP is a good osteoconductive material with similar effects to those of inorganic bovine bone graft and is suitable for utilization in the repair of bone defects. Copyright © 2017 Elsevier GmbH. All rights reserved.

  1. Capillary electrophoresis of inorganic anions.

    PubMed

    Kaniansky, D; Masár, M; Marák, J; Bodor, R

    1999-02-26

    This review deals with the separation mechanisms applied to the separation of inorganic anions by capillary electrophoresis (CE) techniques. It covers various CE techniques that are suitable for the separation and/or determination of inorganic anions in various matrices, including capillary zone electrophoresis, micellar electrokinetic chromatography, electrochromatography and capillary isotachophoresis. Detection and sample preparation techniques used in CE separations are also reviewed. An extensive part of this review deals with applications of CE techniques in various fields (environmental, food and plant materials, biological and biomedical, technical materials and industrial processes). Attention is paid to speciations of anions of arsenic, selenium, chromium, phosphorus, sulfur and halogen elements by CE.

  2. Gravimetric chemical sensors based on silica-based mesoporous organic-inorganic hybrids.

    PubMed

    Xu, Jiaqiang; Zheng, Qi; Zhu, Yongheng; Lou, Huihui; Xiang, Qun; Cheng, Zhixuan

    2014-09-01

    Silica-based mesoporous organic-inorganic hybrid material modified quartz crystal microbalance (QCM) sensors have been examined for their ability to achieve highly sensitive and selective detection. Mesoporous silica SBA-15 serves as an inorganic host with large specific surface area, facilitating gas adsorption, and thus leads to highly sensitive response; while the presence of organic functional groups contributes to the greatly improved specific sensing property. In this work, we summarize our efforts in the rational design and synthesis of novel sensing materials for the detection of hazardous substances, including simulant nerve agent, organic vapor, and heavy metal ion, and develop high-performance QCM-based chemical sensors.

  3. Inorganic Polymers.

    DTIC Science & Technology

    1987-07-16

    inorganic plastics since the siloxanes . They have great potential and may in time prove to be even more useful than the polysiloxanes since many of these...important new class of seni-inorganic plastics since the siloxanes . They have great potential and may in time prove to be even more useful than the... biomedical qualities and useful engineering material parameters, toxicological, corrosion and fire resistance characteristics place many of the

  4. Understanding the Low-Energy Dynamics of Inorganic Fullerene-Like WS2 Nanoparticles

    NASA Astrophysics Data System (ADS)

    Luttrell, R. D.; Rosentsveig, R.

    2005-03-01

    Inorganic fullerene-like nanoparticles are attracting attention due to their outstanding solid-state lubricating behavior. We present the vibrational response of inorganic fullerene-like WS2 nanoparticles and discuss the effects of local strain and effective charge on the dynamics of this material. We compare these results to those of the chemically identical (but morphologically different) layered solid.

  5. Two-Dimensional-Material Membranes: A New Family of High-Performance Separation Membranes.

    PubMed

    Liu, Gongping; Jin, Wanqin; Xu, Nanping

    2016-10-17

    Two-dimensional (2D) materials of atomic thickness have emerged as nano-building blocks to develop high-performance separation membranes that feature unique nanopores and/or nanochannels. These 2D-material membranes exhibit extraordinary permeation properties, opening a new avenue to ultra-fast and highly selective membranes for water and gas separation. Summarized in this Minireview are the latest ground-breaking studies in 2D-material membranes as nanosheet and laminar membranes, with a focus on starting materials, nanostructures, and transport properties. Challenges and future directions of 2D-material membranes for wide implementation are discussed briefly. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. THE ROLE OF MEMBRANE TRANSPORTERS IN THE CELLULAR METABOLISM OF ARSENIC

    EPA Science Inventory

    Arsenic (+3 oxidation state) methyltransferase (AS3MT) catalyzes methylation of inorganic arsenic (iAs) in humans. In this pathway iAs is converted to mono- (MAs) and dimethylated (DMAs) metabolites containing either AsIII or AsV. Because toxicities and meta...

  7. Molten salt battery having inorganic paper separator

    DOEpatents

    Walker, Jr., Robert D.

    1977-01-01

    A high temperature secondary battery comprises an anode containing lithium, a cathode containing a chalcogen or chalcogenide, a molten salt electrolyte containing lithium ions, and a separator comprising a porous sheet comprising a homogenous mixture of 2-20 wt.% chrysotile asbestos fibers and the remainder inorganic material non-reactive with the battery components. The non-reactive material is present as fibers, powder, or a fiber-powder mixture.

  8. Synthesis and characterization of chitosan-polyvinyl alcohol-bioactive glass hybrid membranes.

    PubMed

    Dias, Luisa L S; Mansur, Herman S; Donnici, Claudio Luis; Pereira, Marivalda M

    2011-01-01

    The tissue engineering strategy is a new approach for the regeneration of cementum, which is essential for the regeneration of the periodontal tissue. This strategy involves the cell cultures present in this tissue, called cementoblasts, and located on an appropriate substrate for posterior implantation in the regeneration site. Prior studies from our research group have shown that the proliferation and viability of cementoblasts increase in the presence of the ionic dissolution products of bioactive glass particles. Therefore, one possible approach to obtaining adequate substrates for cementoblast cultures is the development of composite membranes containing bioactive glass. In the present study, composite films of chitosan-polyvinyl alcohol-bioactive glass containing different glass contents were developed. Glutaraldehyde was also added to allow for the formation of cross-links and changes in the degradation rate. The glass phase was introduced in the material by a sol-gel route, leading to an organic-inorganic hybrid. The films were characterized by Fourier-transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM) with electron dispersive spectroscopy (EDS) and X-ray diffraction (XRD) analysis. Bioactivity tests were also conducted by immersion of the films in simulated body fluid (SBF). Films containing up to 30% glass phase could be obtained. The formation of calcium phosphate was observed after the immersion of the films. A calcium phosphate layer formed more quickly on materials containing higher bioactive glass contents. In the hybrid containing 23% bioactive glass, a complete layer was formed after 24 h immersion, showing the high bioactivity of this material. However, despite the higher in vitro bioactivity, the film with 23% glass showed lower mechanical properties compared with films containing up to 17% glass.

  9. Polymer Composite and Nanocomposite Dielectric Materials for Pulse Power Energy Storage †

    PubMed Central

    Barber, Peter; Balasubramanian, Shiva; Anguchamy, Yogesh; Gong, Shushan; Wibowo, Arief; Gao, Hongsheng; Ploehn, Harry J.; zur Loye, Hans-Conrad

    2009-01-01

    This review summarizes the current state of polymer composites used as dielectric materials for energy storage. The particular focus is on materials: polymers serving as the matrix, inorganic fillers used to increase the effective dielectric constant, and various recent investigations of functionalization of metal oxide fillers to improve compatibility with polymers. We review the recent literature focused on the dielectric characterization of composites, specifically the measurement of dielectric permittivity and breakdown field strength. Special attention is given to the analysis of the energy density of polymer composite materials and how the functionalization of the inorganic filler affects the energy density of polymer composite dielectric materials.

  10. Advanced Materials for PEM-Based Fuel Cell Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    James E. McGrath

    2005-10-26

    Proton exchange membrane fuel cells (PEMFCs) are quickly becoming attractive alternative energy sources for transportation, stationary power, and small electronics due to the increasing cost and environmental hazards of traditional fossil fuels. Two main classes of PEMFCs include hydrogen/air or hydrogen/oxygen fuel cells and direct methanol fuel cells (DMFCs). The current benchmark membrane for both types of PEMFCs is Nafion, a perfluorinated sulfonated copolymer made by DuPont. Nafion copolymers exhibit good thermal and chemical stability, as well as very high proton conductivity under hydrated conditions at temperatures below 80 °C. However, application of these membranes is limited due to theirmore » high methanol permeability and loss of conductivity at high temperatures and low relative humidities. These deficiencies have led to the search for improved materials for proton exchange membranes. Potential PEMs should have good thermal, hydrolytic, and oxidative stability, high proton conductivity, selective permeability, and mechanical durability over long periods of time. Poly(arylene ether)s, polyimides, polybenzimidazoles, and polyphenylenes are among the most widely investigated candidates for PEMs. Poly(arylene ether)s are a promising class of proton exchange membranes due to their excellent thermal and chemical stability and high glass transition temperatures. High proton conductivity can be achieved through post-sulfonation of poly(arylene ether) materials, but this most often results in very high water sorption or even water solubility. Our research has shown that directly polymerized poly(arylene ether) copolymers show important advantages over traditional post-sulfonated systems and also address the concerns with Nafion membranes. These properties were evaluated and correlated with morphology, structure-property relationships, and states of water in the membranes. Further improvements in properties were achieved through incorporation of inorganic fillers, such as phosphotungstic acid and zirconium hydrogen phosphate. Block copolymers were also studied due to the possibility to achieve a desired combination of homopolymer properties as well as the unique morphologies that are possible with block copolymers. Bezoyl substituted poly(p-phenylene) blocks were combined with poly(arylene ether) blocks to merge the structural rigidity of the poly(p-phenylene) with the ductility and high protonic conductivity of the poly(arylene ether)s. As evidenced by our many refereed publications and preprints, the research that we have conducted over the past several years has made a valuable and significant contribution to the literature and to the state of understanding of proton exchange membranes. Our early efforts at scale-up have suggested that the directly polymerized disulfonated poly(arylene ether sulfone) copolymers are commercially viable alternatives for proton exchange membranes. A new process for bipolar plates was developed and is described. An important single domain PEMFC model was developed and is documented in this final report.« less

  11. Method of dye removal for the textile industry

    DOEpatents

    Stone, Mark L.

    2000-01-01

    The invention comprises a method of processing a waste stream containing dyes, such as a dye bath used in the textile industry. The invention comprises using an inorganic-based polymer, such as polyphosphazene, to separate dyes and/or other chemicals from the waste stream. Membranes comprising polyphosphazene have the chemical and thermal stability to survive the harsh, high temperature environment of dye waste streams, and have been shown to completely separate dyes from the waste stream. Several polyphosplhazene membranes having a variety of organic substituent have been shown effective in removing color from waste streams.

  12. Design of Bioactive Organic-inorganic Hybrid Materials with Self-setting Ability

    NASA Astrophysics Data System (ADS)

    Miyazaki, T.; Machida, S.; Morita, Y.; Ishida, E.

    2011-10-01

    Paste-like materials with ability of self-setting are attractive for bone substitutes, since they can be injected from the small hole with minimized invasion to the patient. Although bone cements which set as apatite are clinically used, there is limitation on clinical applications due to their mechanical properties such as high brittleness and low fracture toughness. To overcome this problem, organic-inorganic hybrids based on a flexible polymer are attractive. We have obtained an idea for design of self-setting hybrids using polyion complex fabricated by ionic interaction of anionic and cationic polymers. We aimed at preparation of organic-inorganic hybrids exhibiting self-setting ability and bioactivity. The liquid component was prepared from cationic chitosan aqueous solution. The powder component was prepared by mixing various carrageenans with α-tricalcium phosphate (α-TCP). The obtained cements set within 1 day. Compressive strength showed tendency to increase with increase in α-TCP content in the powder component. The prepared cements formed the apatite in simulated body fluid within 3 days. Novel self-setting materials based on organic-inorganic hybrid can be designed utilizing ionic interaction of polysaccharide.

  13. Integrated ion sensor device applications based on printed hybrid material systems (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    List-Kratochvil, Emil J. W.

    2016-09-01

    Comfortable, wearable sensors and computers will enhance every person's awareness of his or her health condition, environment, chemical pollutants, potential hazards, and information of interest. In agriculture and in the food industry there is a need for a constant control of the condition and needs of plants, animals, and farm products. Yet many of these applications depend upon the development of novel, cheap devices and sensors that are easy to implement and to integrate. Organic semiconductors as well as several inorganic materials and hybrid material systems have proven to combine a number of intriguing optical and electronic properties with simple processing methods. As it will be reviewed in this contribution, these materials are believed to find their application in printed electronic devices allowing for the development of smart disposable devices in food-, health-, and environmental monitoring, diagnostics and control, possibly integrated into arrays of sensor elements for multi-parameter detection. In this contribution we review past and recent achievements in the field. Followed by a brief introduction, we will focus on two topics being on the agenda recently: a) the use of electrolyte-gated organic field-effect transistor (EGOFET) and ion-selective membrane based sensors for in-situ sensing of ions and biological substances and b) the development of hybrid material based resistive switches and their integration into fully functional, printed hybrid crossbar sensor array structures.

  14. Method and apparatus for hydrogen production from water

    NASA Technical Reports Server (NTRS)

    Muradov, Nazim Z. (Inventor)

    2012-01-01

    A method, apparatuses and chemical compositions are provided for producing high purity hydrogen from water. Metals or alloys capable of reacting with water and producing hydrogen in aqueous solutions at ambient conditions are reacted with one or more inorganic hydrides capable of releasing hydrogen in aqueous solutions at ambient conditions, one or more transition metal compounds are used to catalyze the reaction and, optionally, one or more alkali metal-based compounds. The metal or alloy is preferably aluminum. The inorganic hydride is from a family of complex inorganic hydrides; most preferably, NaBH.sub.4. The transition metal catalyst is from the groups VIII and IB; preferably, Cu and Fe. The alkali metal-based compounds are preferably NaOH, KOH, and the like. Hydrogen generated has a purity of at least 99.99 vol. % (dry basis), and is used without further purification in all types of fuel cells, including the polymer electrolyte membrane (PEM) fuel cell.

  15. Synthetic Strategies in the Preparation of Polymer/Inorganic Hybrid Nanoparticles

    PubMed Central

    Hood, Matthew A.; Mari, Margherita; Muñoz-Espí, Rafael

    2014-01-01

    This article reviews the recent advances and challenges in the preparation of polymer/inorganic hybrid nanoparticles. We mainly focus on synthetic strategies, basing our classification on whether the inorganic and the polymer components have been formed in situ or ex situ, of the hybrid material. Accordingly, four types of strategies are identified and described, referring to recent examples: (i) ex situ formation of the components and subsequent attachment or integration, either by covalent or noncovalent bonding; (ii) in situ polymerization in the presence of ex situ formed inorganic nanoparticles; (iii) in situ precipitation of the inorganic components on or in polymer structures; and (iv) strategies in which both polymer and inorganic component are simultaneously formed in situ. PMID:28788665

  16. Does chlorination of seawater reverse osmosis membranes control biofouling?

    PubMed

    Khan, Muhammad Tariq; Hong, Pei-Ying; Nada, Nabil; Croue, Jean Philippe

    2015-07-01

    Biofouling is the major problem of reverse osmosis (RO) membranes used for desalting seawater (SW). The use of chlorine is a conventional and common practice to control/prevent biofouling. Unlike polyamide RO membranes, cellulose triacetate (CTA) RO membranes display a high chlorine tolerance. Due to this characteristic, CTA membranes are used in most of the RO plants located in the Middle East region where the elevated seawater temperature and water quality promote the risk of membrane biofouling. However, there is no detailed study on the investigation/characterization of CTA-RO membrane fouling. In this investigation, the fouling profile of a full-scale SWRO desalination plant operating with not only continuous chlorination of raw seawater but also intermittent chlorination of CTA-RO membranes was studied. Detailed water quality and membrane fouling analyses were conducted. Profiles of microbiological, inorganic, and organic constituents of analysed fouling layers were extensively discussed. Our results clearly identified biofilm development on these membranes. The incapability of chlorination on preventing biofilm formation on SWRO membranes could be assigned to its failure in effectively reaching throughout the different regions of the permeators. This failure could have occurred due to three main factors: plugging of membrane fibers, chlorine consumption by organics accumulated on the front side fibers, or chlorine adaptation of certain bacterial populations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Gold nanoparticles-induced enhancement of the analytical response of an electrochemical biosensor based on an organic-inorganic hybrid composite material.

    PubMed

    Barbadillo, M; Casero, E; Petit-Domínguez, M D; Vázquez, L; Pariente, F; Lorenzo, E

    2009-12-15

    The design and characterization of a new organic-inorganic hybrid composite material for glucose electrochemical sensing are described. This material is based on the entrapment of both gold nanoparticles (AuNPs) and glucose oxidase, which was chosen as a model, into a sol-gel matrix. The addition of spectroscopic grade graphite to this system, which confers conductivity, leads to the development of a material particularly attractive for electrochemical biosensor fabrication. The characterization of the hybrid composite material was performed using atomic force microscopy and scanning electron microscopy techniques. This composite material was applied to the determination of glucose in presence of hydroxymethylferrocene as a redox mediator. The system exhibits a clear electrocatalytic activity towards glucose, allowing its determination at 250 mV vs Ag/AgCl. The performance of the resulting enzyme biosensor was evaluated in terms of sensitivity, detection limit, linear response range, stability and accuracy. Finally, the enhancement of the analytical response of the resulting biosensor induced by the presence of gold nanoparticles was evaluated by comparison with a similar organic-inorganic hybrid composite material without AuNPs.

  18. Mercouri G. Kanatzidis: Excellence and Innovations in Inorganic and Solid-State Chemistry.

    PubMed

    Arachchige, Indika U; Armatas, Gerasimos S; Biswas, Kanishka; Subrahmanyam, Kota S; Latturner, Susan; Malliakas, Christos D; Manos, Manolis J; Oh, Youngtak; Polychronopoulou, Kyriaki; P Poudeu, Pierre F; Trikalitis, Pantelis N; Zhang, Qichun; Zhao, Li-Dong; Peter, Sebastian C

    2017-07-17

    Over the last 3-4 decades, solid-state chemistry has emerged as the forefront of materials design and development. The field has revolutionized into a multidisciplinary subject and matured with a scope of new synthetic strategies, new challenges, and opportunities. Understanding the structure is very crucial in the design of appropriate materials for desired applications. Professor Mercouri G. Kanatzidis has encountered both challenges and opportunities during the course of the discovery of many novel materials. Throughout his scientific career, Mercouri and his group discovered several inorganic compounds and pioneered structure-property relationships. We, a few Ph.D. and postdoctoral students, celebrate his 60th birthday by providing a Viewpoint summarizing his contributions to inorganic solid-state chemistry. The topics discussed here are of significant interest to various scientific communities ranging from condensed matter to green energy production.

  19. Hybrid Silicon-Based Organic/Inorganic Block Copolymers with Sol-Gel Active Moieties: Synthetic Advances, Self-Assembly and Applications in Biomedicine and Materials Science.

    PubMed

    Czarnecki, Sebastian; Bertin, Annabelle

    2018-03-07

    Hybrid silicon-based organic/inorganic (multi)block copolymers are promising polymeric precursors to create robust nano-objects and nanomaterials due to their sol-gel active moieties via self-assembly in solution or in bulk. Such nano-objects and nanomaterials have great potential in biomedicine as nanocarriers or scaffolds for bone regeneration as well as in materials science as Pickering emulsifiers, photonic crystals or coatings/films with antibiofouling, antibacterial or water- and oil-repellent properties. Thus, this Review outlines recent synthetic efforts in the preparation of these hybrid inorganic/organic block copolymers, gives an overview of their self-assembled structures and finally presents recent examples of their use in the biomedical field and material science. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Organic-Inorganic Hybrid Ruddlesden-Popper Perovskites: An Emerging Paradigm for High-Performance Light-Emitting Diodes.

    PubMed

    Liu, Xiao-Ke; Gao, Feng

    2018-05-03

    Recently, lead halide perovskite materials have attracted extensive interest, in particular, in the research field of solar cells. These materials are fascinating "soft" materials with semiconducting properties comparable to the best inorganic semiconductors like silicon and gallium arsenide. As one of the most promising perovskite family members, organic-inorganic hybrid Ruddlesden-Popper perovskites (HRPPs) offer rich chemical and structural flexibility for exploring excellent properties for optoelectronic devices, such as solar cells and light-emitting diodes (LEDs). In this Perspective, we present an overview of HRPPs on their structural characteristics, synthesis of pure HRPP compounds and thin films, control of their preferential orientations, and investigations of heterogeneous HRPP thin films. Based on these recent advances, future directions and prospects have been proposed. HRPPs are promising to open up a new paradigm for high-performance LEDs.

  1. Force-controlled inorganic crystallization lithography.

    PubMed

    Cheng, Chao-Min; LeDuc, Philip R

    2006-09-20

    Lithography plays a key role in integrated circuits, optics, information technology, biomedical applications, catalysis, and separation technologies. However, inorganic lithography techniques remain of limited utility for applications outside of the typical foci of integrated circuit manufacturing. In this communication, we have developed a novel stamping method that applies pressure on the upper surface of the stamp to regulate the dewetting process of the inorganic buffer and the evaporation rate of the solvent in this buffer between the substrate and the surface of the stamp. We focused on generating inorganic microstructures with specific locations and also on enabling the ability to pattern gradients during the crystallization of the inorganic salts. This approach utilized a combination of lithography with bottom-up growth and assembly of inorganic crystals. This work has potential applications in a variety of fields, including studying inorganic material patterning and small-scale fabrication technology.

  2. Nanomaterials and Water Purification: Opportunities and Challenges

    NASA Astrophysics Data System (ADS)

    Savage, Nora; Diallo, Mamadou S.

    2005-10-01

    Advances in nanoscale science and engineering suggest that many of the current problems involving water quality could be resolved or greatly ameliorated using nanosorbents, nanocatalysts, bioactive nanoparticles, nanostructured catalytic membranes and nanoparticle enhanced filtration among other products and processes resulting from the development of nanotechnology. Innovations in the development of novel technologies to desalinate water are among the most exciting and promising. Additionally, nanotechnology-derived products that reduce the concentrations of toxic compounds to sub-ppb levels can assist in the attainment of water quality standards and health advisories. This article gives an overview of the use of nanomaterials in water purification. We highlight recent advances on the development of novel nanoscale materials and processes for treatment of surface water, groundwater and industrial wastewater contaminated by toxic metal ions, radionuclides, organic and inorganic solutes, bacteria and viruses. In addition, we discuss some challenges associated with the development of cost effective and environmentally acceptable functional nanomaterials for water purification.

  3. 77 FR 4522 - National Emission Standards for Hazardous Air Pollutants for Chemical Manufacturing Area Sources

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-30

    ... Manufacturing, Industrial Organic Chemical Manufacturing, Inorganic Pigments Manufacturing, Miscellaneous Organic Chemical Manufacturing, Plastic Materials and Resins Manufacturing, Pharmaceutical Production and... Intermediate Production, Industrial Inorganic Chemical Manufacturing, Industrial Organic Chemical Manufacturing...

  4. 40 CFR 264.314 - Special requirements for bulk and containerized liquids.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) Inorganic minerals, other inorganic materials, and elemental carbon (e.g., aluminosilicates, clays... (ii) High molecular weight synthetic polymers (e.g., polyethylene, high density polyethylene (HDPE), polypropylene, polystyrene, polyurethane, polyacrylate, polynorborene, polyisobutylene, ground synthetic rubber...

  5. Adsorption of p-cresol on novel diatomite/carbon composites.

    PubMed

    Hadjar, H; Hamdi, B; Ania, C O

    2011-04-15

    Hybrid inorganic/organic adsorbents were synthesized using mixtures of diatomite and carbon charcoal as precursors, and explored for the removal of p-cresol from aqueous solution. The carbon/diatomite composites displayed a bimodal and interconnected porous structure which was partially inherited from both precursors. They display moderate surface areas (between 100 and 400 m(2)g(-1)) due to their large inorganic content (between 70 and 90 wt.%), since the diatomite is a non-porous material. Compared to activated carbons with a more developed porosity, p-cresol adsorption on the prepared carbon/diatomite composites was much faster, showing adsorption capacities similar to those of conventional adsorbents over a wide pH range. These results show a good affinity of p-cresol molecules towards the hybrid inorganic/organic composites, and demonstrate the suitability of these novel materials for the removal of aromatic (polar) molecules, despite their dominant inorganic character. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. An inorganic boronate affinity in-needle monolithic device for specific capture of cis-diol containing compounds.

    PubMed

    Jin, Shanxia; Zhang, Wei; Yang, Qin; Dai, Lili; Zhou, Ping

    2018-02-01

    In this work, inorganic boronate affinity monolith was prepared by in situ synthesis in 0.33mm i.d. stainless steel needle through sol-gel process using tetraethoxysilane and tetrabutyl orthotitanate as the co-precursors. The morphology, structure and composition of the monolith were characterized. In contrast to conventional boronate affinity materials, inorganic boric acid was used as affinity ligand. Different compounds were used for the evaluation of the boronate affinity of this inorganic monolithic material. The monolith exhibited good selectivity towards cis-diol containing compounds. Recovery of greater than 90% was achieved for in-needle extraction of catechol under neutral conditions. Owing to the hydrophilic property of the monolith, the procedure of affinity chromatography could be performed in aqueous solution. This monolithic in-needle device will be useful for boronate affinity extraction of small-volume samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Nanostructured Interfaces for Organized Mesoscopic Biotic-Abiotic Materials

    DTIC Science & Technology

    2011-09-30

    stratified films. Bio-assisted and surface-mediated growth of inorganic nanoparticles . The use of biomolecules as templates for the synthesis of...multi-length scale morphologies of several selected inorganic materials including bi-metal nanoparticles (Au-Ag, Au-Pd) as well as TiO2, ZnO nanodots...polyaminoacid-decorated surfaces which serve for both nucleation and growth of uniformly distributed gold nanoparticles at ambient conditions. We found that

  8. Effects of Residual Solvent Molecules Facilitating the Infiltration Synthesis of ZnO in a Nonreactive Polymer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ye, Xinyi; Kestell, John; Kisslinger, Kim

    Infiltration synthesis, the atomic-layer-deposition-based organic–inorganic material hybridization technique that enables unique hybrid composites with improved material properties and inorganic nanostructures replicated from polymer templates, is shown to be driven by the binding reaction between reactive chemical groups of polymers and perfusing vapor-phase material precursors. Here in this paper, we discover that residual solvent molecules from polymer processing can react with infiltrating material precursors to enable the infiltration synthesis of metal oxides in a nonreactive polymer. The systematic study, which combines in situ quartz crystal microgravimetry, polarization-modulated infrared reflection–absorption spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy, shows that the ZnOmore » infiltration synthesis in nominally nonreactive SU-8 polymer is mediated by residual processing solvent cyclopentanone, a cyclic ketone whose Lewis-basic terminal carbonyl group can react with the infiltrating Lewis-acidic Zn precursor diethylzinc (DEZ). In addition, we find favorable roles of residual epoxy rings in the SU-8 film in further assisting the infiltration synthesis of ZnO. Lastly, the discovered rationale not only improves the understanding of infiltration synthesis mechanism, but also potentially expands its application to more diverse polymer systems for the generation of unique functional organic–inorganic hybrids and inorganic nanostructures.« less

  9. "Rinse and trickle": a protocol for TEM preparation and investigation of inorganic fibers from biological material.

    PubMed

    Vigliaturo, Ruggero; Capella, Silvana; Rinaudo, Caterina; Belluso, Elena

    2016-07-01

    The purpose of this work is to define a sample preparation protocol that allows inorganic fibers and particulate matter extracted from different biological samples to be characterized morphologically, crystallographically and chemically by transmission electron microscopy-energy dispersive spectroscopy (TEM-EDS). The method does not damage or create artifacts through chemical attacks of the target material. A fairly rapid specimen preparation is applied with the aim of performing as few steps as possible to transfer the withdrawn inorganic matter onto the TEM grid. The biological sample is previously digested chemically by NaClO. The salt is then removed through a series of centrifugation and rinse cycles in deionized water, thus drastically reducing the digestive power of the NaClO and concentrating the fibers for TEM analysis. The concept of equivalent hydrodynamic diameter is introduced to calculate the settling velocity during the centrifugation cycles. This technique is applicable to lung tissues and can be extended to a wide range of organic materials. The procedure does not appear to cause morphological damage to the fibers or modify their chemistry or degree of crystallinity. The extrapolated data can be used in interdisciplinary studies to understand the pathological effects caused by inorganic materials.

  10. Effects of Residual Solvent Molecules Facilitating the Infiltration Synthesis of ZnO in a Nonreactive Polymer

    DOE PAGES

    Ye, Xinyi; Kestell, John; Kisslinger, Kim; ...

    2017-05-04

    Infiltration synthesis, the atomic-layer-deposition-based organic–inorganic material hybridization technique that enables unique hybrid composites with improved material properties and inorganic nanostructures replicated from polymer templates, is shown to be driven by the binding reaction between reactive chemical groups of polymers and perfusing vapor-phase material precursors. Here in this paper, we discover that residual solvent molecules from polymer processing can react with infiltrating material precursors to enable the infiltration synthesis of metal oxides in a nonreactive polymer. The systematic study, which combines in situ quartz crystal microgravimetry, polarization-modulated infrared reflection–absorption spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy, shows that the ZnOmore » infiltration synthesis in nominally nonreactive SU-8 polymer is mediated by residual processing solvent cyclopentanone, a cyclic ketone whose Lewis-basic terminal carbonyl group can react with the infiltrating Lewis-acidic Zn precursor diethylzinc (DEZ). In addition, we find favorable roles of residual epoxy rings in the SU-8 film in further assisting the infiltration synthesis of ZnO. Lastly, the discovered rationale not only improves the understanding of infiltration synthesis mechanism, but also potentially expands its application to more diverse polymer systems for the generation of unique functional organic–inorganic hybrids and inorganic nanostructures.« less

  11. Applying fermentation liquid of food waste as carbon source to a pilot-scale anoxic/oxic-membrane bioreactor for enhancing nitrogen removal: Microbial communities and membrane fouling behaviour.

    PubMed

    Tang, Jialing; Wang, Xiaochang C; Hu, Yisong; Ngo, Huu Hao; Li, Yuyou; Zhang, Yongmei

    2017-07-01

    Fermentation liquid of food waste (FLFW) was applied as an external carbon source in a pilot-scale anoxic/oxic-membrane bioreactor (A/O-MBR) system to enhance nitrogen removal for treating low COD/TN ratio domestic wastewater. Results showed that, with the FLFW addition, total nitrogen removal increased from lower than 20% to 44-67% during the 150days of operation. The bacterial metabolic activities were obviously enhanced, and the significant change in microbial community structure promoted pollutants removal and favored membrane fouling mitigation. By monitoring transmembrane pressure and characterizing typical membrane foulants, such as extracellular polymeric substances (EPS), dissolved organic matter (DOM), and inorganics and biopolymers in the cake layer, it was confirmed that FLFW addition did not bring about any additional accumulation of membrane foulants, acceleration of fouling rate, or obvious irreversible membrane fouling in the whole operation period. Therefore, FLFW is a promising alternative carbon source to enhance nitrogen removal for the A/O-MBR system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Membrane fouling control and enhanced removal of pharmaceuticals and personal care products by coagulation-MBR.

    PubMed

    Park, Junwon; Yamashita, Naoyuki; Tanaka, Hiroaki

    2018-04-01

    We investigated the effects of the addition of two coagulants-polyaluminium chloride (PACl) and chitosan-into the membrane bioreactor (MBR) process on membrane fouling and the removal of pharmaceuticals and personal care products (PPCPs). Their addition at optimized dosages improved the permeability of the membrane by reducing the concentration of soluble microbial products in mixed liquor, the content of inorganic elements, and irreversible fouling of the membrane surface. During long-term operation, the addition of PACl increased removal efficiencies of tetracycline, mefenamic acid, atenolol, furosemide, ketoprofen, and diclofenac by 17-23%. The comparative evaluation using mass balance calculations between coagulation-MBR (with PACl addition) and control-MBR (without PACl addition) showed that enhanced biodegradability played a key role in improving removal efficiencies of some PPCPs in coagulation-MBR. Coagulation-MBR also had higher oxygen uptake rates and specific nitrification rates of microorganisms. Overall, our findings suggest that the combination of MBR with coagulation reduced membrane fouling, lengthening operation period of the membrane, and improved the removal of some PPCPs as a result of enhanced biodegradability. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Sol-gel processing with inorganic metal salt precursors

    DOEpatents

    Hu, Zhong-Cheng

    2004-10-19

    Methods for sol-gel processing that generally involve mixing together an inorganic metal salt, water, and a water miscible alcohol or other organic solvent, at room temperature with a macromolecular dispersant material, such as hydroxypropyl cellulose (HPC) added. The resulting homogenous solution is incubated at a desired temperature and time to result in a desired product. The methods enable production of high quality sols and gels at lower temperatures than standard methods. The methods enable production of nanosize sols from inorganic metal salts. The methods offer sol-gel processing from inorganic metal salts.

  14. Processing and surface modification of novel natural-origin architectures aimed for biomedical applications

    NASA Astrophysics Data System (ADS)

    Silva, Simone dos Santos

    In the last decades, tissue engineering has emerged as a potential therapeutical tool aimed at developing substitutes that are able to restore proper function of the damaged organs/tissues. Nature-inspired routes involving natural origin polymer-based systems represent an attractive alternative to produce novel materials by mimicking the tissue environment required for tissue regeneration. Moreover, further modifications of these systems allow the adjustment of their properties in accordance with the requirements for successful biomedical applications. The main goal of the present thesis is to develop and modify natural origin polymer-based systems using simple methodologies such as sol-gel, surface modification by means of plasma treatment and blending of chitosan with proteins (soy protein isolate and silk fibroin). A sol-gel method was used to improve the bulk properties of chitosan by the incorporation of an inorganic component at the sub-nanometric level. Chitosan/siloxane hybrid materials were synthesised, where essentially urea bridges covalently bond the chitosan to the polysiloxane network. These bifunctional materials exhibit interesting photoluminescence features and a bioactive behaviour. In most situations in the biomedical field, the surface of a biomaterial is in direct contact with living tissues. Therefore, the surface characteristics play a fundamental role on the implant biocompatibility. In this thesis, nitrogen and argon plasma treatment was applied on chitosan membranes in order to improve their surface properties. The applied modifications promoted differences on surface chemistry, wettability and roughness, which reflected in a significant improvement of fibroblast adhesion and proliferation onto chitosan membranes. Besides the surface modification, blending of chitosan with proteins such as soy protein isolate and silk fibroin was also used to modify the bulk properties of chitosan. In situ cross-linking with glutaraldehyde solutions was used to enhance the interaction between the components of the blend. Hence, membranes with different morphologies, water absorption and degradability were obtained. The biological assays suggested that the cross-linking with lower glutaraldehyde concentration promotes better cell adhesion on the membranes. The morphological characterization showed that both surface roughness surface and surface energy were dependent on soy protein content. Structural investigations by FTIR and NMR indicated that the blends are not completely miscible due to a weak polysaccharide-protein interaction. In another related work, novel hydrogels were produced combining Bombyx mori silk fibroin and chitosan. In this case, these systems were cross-linked with genipin. These hydrogels were freeze dried to obtain cross-linked chitosan/silk sponges. Rheological and mechanical properties, structural aspects and morphological features of the porous structures were evaluated. The results revealed stable and ordered structures, similar porosities, and swelling capability that depended on the pH. The cytotoxicity assay indicated that cellular viability was about 100% in all sponges and for all time points studied (1, 3, 7 and 14 days), demonstrating the extremely low cytotoxicity levels of the materials. Cell studies using chondrocytes-like cells seeded onto sponges, including cell viability (MTS assay), proliferation (DNA test), morphology (SEM analysis) and matrix production (GAGs quantification), showed a significant high adhesion, proliferation and matrix production with the time of culture. The findings in this work suggested that the properties of the sponges can be manipulated by either change chitosan/silk fibroin ratio or through genipin cross-linking. Parallel to this study, the possibility of obtaining modified silk nanometric nets using electrospinning processing from regenerated silk fibroin/formic acid with addition of genipin was explored. Modified silk nanofibers with diameters ranging from 140 nm to 590 nm were developed. The changes on the secondary structure of nanofibers, induced by the reaction of silk fibroin with genipin, promoted a higher integrity of these modified nanofibers in water. In summary, the findings from these works demonstrated the potential and versatility of the proposed strategies in obtaining different structures (e.g. membranes, hydrogels) using mixtures of chitosan with proteins or with inorganic agents for improving the performance of natural origin polymer-based materials to be used in biomedical applications.

  15. Inorganic and metal nanoparticles and their antimicrobial activity in food packaging applications.

    PubMed

    Hoseinnejad, Mahmoud; Jafari, Seid Mahdi; Katouzian, Iman

    2018-03-01

    Nanotechnology has revolutionized almost all the fields of science and technology, particularly the food packaging industry. Accordingly, some nanoparticles can be used in food contact materials to preserve food products for longer periods. To date, many inorganic and metal nanoparticles have been implemented to synthesize active food packaging materials and to extend the shelf-life of foods. Packaging with nanocomposites containing these nanoparticles offers advantages, such as reduction in the usage of preservatives and higher rate of reactions to inhibit the microbial growth. Nevertheless, the safety issues of employing the metal and inorganic nanoparticles in food packaging are still a major concern and more studies along with clinical trials need to be carried out prior to the mass production of these promising food containers. In this review, we have evaluated recent studies plus the applications of inorganic and metal nanoparticles mostly in food packaging applications along with their antimicrobial properties and reaction mechanisms. Many examples have been provided with the aim of opening new horizons for researchers to implement inorganic and metal nanoparticles in active food packaging field.

  16. Metabolic similarities between fertilization and phagocytosis. Conservation of a peroxidatic mechanism

    PubMed Central

    1979-01-01

    At the time of fertilization, sea urchin eggs release a peroxidase which, together with H2O2 generated by a respiratory burst, is responsible for hardening of the fertilization membrane. We demonstrate here that the ovoperoxidase of unfertilized eggs is located in cortical granules and, after fertilization, is concentrated in the fertilization membrane. Fertilization of sea urchin eggs or their parthenogenetic activation with the ionophor A23187 also results in (a) the conversion of iodide to a trichloroacetic acid-precipitable form (iodination), (b) the deiodination of eggs exogenously labeled with myeloperoxidase and H2O2, (c) the degradation of thyroxine as measured by the recovery of the released radioiodine at the origin and in the inorganic iodide spot on paper chromatography, and (d) the conversion of estradiol to an alcohol-precipitable form (estrogen binding). The iodination reaction and the binding of estradio occurs predominantly in the fertilization membrane where the ovoperoxidase is concentrated. From the estimation of the kinetics of incorporation of iodine, we determine that the peroxidative system is active for 30 min after fertilization, long after hardening of the fertilization membrane is complete. Most of the bound iodine is lost during the hatching process. Iodination of albumin is catalyzed by the material released from the egg during fertilization, when combined with H2O2 and iodide. Iodination, thyroxine degradation, and estradiol binding are inhibited by azide, cyanide, aminotriazole, methimazole, ascorbic acid and ergothioneine, all of which can inhibit peroxidase-catalyzed reactions. These responses of the sea urchin egg to fertilization are strikingly similar to the changes induced in polymorphonuclear leukocytes by phagocytosis and, in both instances, a peroxidative mechanism may be involved. PMID:372484

  17. Sustainable exposure prevention through innovative detection and remediation technologies from the NIEHS Superfund Research Program.

    PubMed

    Henry, Heather F; Suk, William A

    2017-03-01

    Innovative devices and tools for exposure assessment and remediation play an integral role in preventing exposure to hazardous substances. New solutions for detecting and remediating organic, inorganic, and mixtures of contaminants can improve public health as a means of primary prevention. Using a public health prevention model, detection and remediation technologies contribute to primary prevention as tools to identify areas of high risk (e.g. contamination hotspots), to recognize hazards (bioassay tests), and to prevent exposure through contaminant cleanups. Primary prevention success is ultimately governed by the widespread acceptance of the prevention tool. And, in like fashion, detection and remediation technologies must convey technical and sustainability advantages to be adopted for use. Hence, sustainability - economic, environmental, and societal - drives innovation in detection and remediation technology. The National Institute of Health (NIH) National Institute of Environmental Health Sciences (NIEHS) Superfund Research Program (SRP) is mandated to advance innovative detection, remediation, and toxicity screening technology development through grants to universities and small businesses. SRP recognizes the importance of fast, accurate, robust, and advanced detection technologies that allow for portable real-time, on-site characterization, monitoring, and assessment of contaminant concentration and/or toxicity. Advances in non-targeted screening, biological-based assays, passive sampling devices (PSDs), sophisticated modeling approaches, and precision-based analytical tools are making it easier to quickly identify hazardous "hotspots" and, therefore, prevent exposures. Innovation in sustainable remediation uses a variety of approaches: in situ remediation; harnessing the natural catalytic properties of biological processes (such as bioremediation and phytotechnologies); and application of novel materials science (such as nanotechnology, advanced membranes, new carbon materials, and materials reuse). Collectively, the investment in new technologies shows promise to reduce the amount and toxicity of hazardous substances in the environment. This manuscript highlights SRP funded innovative devices and tools for exposure assessment and remediation of organic, inorganic, and mixtures of contaminants with a particular focus on sustainable technologies.

  18. The thermodynamic scale of inorganic crystalline metastability

    PubMed Central

    Sun, Wenhao; Dacek, Stephen T.; Ong, Shyue Ping; Hautier, Geoffroy; Jain, Anubhav; Richards, William D.; Gamst, Anthony C.; Persson, Kristin A.; Ceder, Gerbrand

    2016-01-01

    The space of metastable materials offers promising new design opportunities for next-generation technological materials, such as complex oxides, semiconductors, pharmaceuticals, steels, and beyond. Although metastable phases are ubiquitous in both nature and technology, only a heuristic understanding of their underlying thermodynamics exists. We report a large-scale data-mining study of the Materials Project, a high-throughput database of density functional theory–calculated energetics of Inorganic Crystal Structure Database structures, to explicitly quantify the thermodynamic scale of metastability for 29,902 observed inorganic crystalline phases. We reveal the influence of chemistry and composition on the accessible thermodynamic range of crystalline metastability for polymorphic and phase-separating compounds, yielding new physical insights that can guide the design of novel metastable materials. We further assert that not all low-energy metastable compounds can necessarily be synthesized, and propose a principle of ‘remnant metastability’—that observable metastable crystalline phases are generally remnants of thermodynamic conditions where they were once the lowest free-energy phase. PMID:28138514

  19. Simulations of inorganic-bioorganic interfaces to discover new materials: insights, comparisons to experiment, challenges, and opportunities.

    PubMed

    Heinz, Hendrik; Ramezani-Dakhel, Hadi

    2016-01-21

    Natural and man-made materials often rely on functional interfaces between inorganic and organic compounds. Examples include skeletal tissues and biominerals, drug delivery systems, catalysts, sensors, separation media, energy conversion devices, and polymer nanocomposites. Current laboratory techniques are limited to monitor and manipulate assembly on the 1 to 100 nm scale, time-consuming, and costly. Computational methods have become increasingly reliable to understand materials assembly and performance. This review explores the merit of simulations in comparison to experiment at the 1 to 100 nm scale, including connections to smaller length scales of quantum mechanics and larger length scales of coarse-grain models. First, current simulation methods, advances in the understanding of chemical bonding, in the development of force fields, and in the development of chemically realistic models are described. Then, the recognition mechanisms of biomolecules on nanostructured metals, semimetals, oxides, phosphates, carbonates, sulfides, and other inorganic materials are explained, including extensive comparisons between modeling and laboratory measurements. Depending on the substrate, the role of soft epitaxial binding mechanisms, ion pairing, hydrogen bonds, hydrophobic interactions, and conformation effects is described. Applications of the knowledge from simulation to predict binding of ligands and drug molecules to the inorganic surfaces, crystal growth and shape development, catalyst performance, as well as electrical properties at interfaces are examined. The quality of estimates from molecular dynamics and Monte Carlo simulations is validated in comparison to measurements and design rules described where available. The review further describes applications of simulation methods to polymer composite materials, surface modification of nanofillers, and interfacial interactions in building materials. The complexity of functional multiphase materials creates opportunities to further develop accurate force fields, including reactive force fields, and chemically realistic surface models, to enable materials discovery at a million times lower computational cost compared to quantum mechanical methods. The impact of modeling and simulation could further be increased by the advancement of a uniform simulation platform for organic and inorganic compounds across the periodic table and new simulation methods to evaluate system performance in silico.

  20. Identification and analysis of proton-translocating pyrophosphatases in the methanogenic archaeon Methanosarcina mazei

    PubMed Central

    Bäumer, Sebastian; Lentes, Sabine; Gottschalk, Gerhard; Deppenmeier, Uwe

    2002-01-01

    Analysis of genome sequence data from the methanogenic archaeon Methanosarcina mazei Gö1 revealed the existence of two open reading frames encoding proton-translocating pyrophosphatases (PPases). These open reading frames are linked by a 750-bp intergenic region containing TC-rich stretches and are transcribed in opposite directions. The corresponding polypeptides are referred to as Mvp1 and Mvp2 and consist of 671 and 676 amino acids, respectively. Both enzymes represent extremely hydrophobic, integral membrane proteins with 15 predicted transmembrane segments and an overall amino acid sequence similarity of 50.1%. Multiple sequence alignments revealed that Mvp1 is closely related to eukaryotic PPases, whereas Mvp2 shows highest homologies to bacterial PPases. Northern blot experiments with RNA from methanol-grown cells harvested in the mid-log growth phase indicated that only Mvp2 was produced under these conditions. Analysis of washed membranes showed that Mvp2 had a specific activity of 0.34 U mg (protein)–1. Proton translocation experiments with inverted membrane vesicles prepared from methanol-grown cells showed that hydrolysis of 1 mol of pyrophosphate was coupled to the translocation of about 1 mol of protons across the cytoplasmic membrane. Appropriate conditions for mvp1 expression could not be determined yet. The pyrophosphatases of M. mazei Gö1 represent the first examples of this enzyme class in methanogenic archaea and may be part of their energy-conserving system. Abbreviations: DCCD, N,N′-dicyclohexylcarbodiimide; PPase, inorganic pyrophosphatase; PPi, inorganic pyrophosphate; Δp, proton motive force. PMID:15803653

  1. Transparent organic/inorganic hybrid sol-gel materials based on perfluorinated polymers and silica

    NASA Astrophysics Data System (ADS)

    Wojcik, Anna B.; Klein, Lisa C.

    1996-01-01

    Two types of hybrid gels based on silica and perfluorinated polymers have been prepared. The first type involves a perfluorinated polymer containing acrylate groups. Perfluoropolyether diol diacrylate (PFDA) was functionalized by reacting it with (3-mercapto-propyl) trimethoxysilane by a Michael addition. The resulting silyl derivative (PFDAS) was able to copolymerize with a silica precursor, tetraethylorthosilicate (TEOS), resulting in perfluorinated polymer/silica hybrid gels. For the second type, perfluoroalkylsilane (FAS), vinyltriethoxysilane (VTES), and TEOS were polymerized in one step. In both cases, the gels were transparent, crack-free and water repellent. Since the inorganic and organic components are covalently bonded to each other, these materials can be classified as organic/inorganic copolymers.

  2. Artificial inorganic biohybrids: The functional combination of microorganisms and cells with inorganic materials.

    PubMed

    Holzmeister, Ib; Schamel, Martha; Groll, Jürgen; Gbureck, Uwe; Vorndran, Elke

    2018-04-24

    Biohybrids can be defined as the functional combination of proteins, viable cells or microorganisms with non-biological materials. This article reviews recent findings on the encapsulation of microorganisms and eukaryotic cells in inorganic matrices such as silica gels or cements. The entrapment of biological entities into a support material is of great benefit for processing since the encapsulation matrix protects sensitive cells from shear forces, unfavourable pH changes, or cytotoxic solvents, avoids culture-washout, and simplifies the separation of formed products. After reflecting general aspects of such an immobilization as well as the chemistry of the inorganic matrices, we focused on manufacturing aspects and the application of such biohybrids in biotechnology, medicine as well as in environmental science and for civil engineering purpose. The encapsulation of living cells and microorganisms became an intensively studied and rapidly expanding research field with manifold applications in medicine, bio- and environmental technology, or civil engineering. Here, the use of silica or cements as encapsulation matrices have the advantage of a higher chemical and mechanical resistance towards harsh environmental conditions during processing compared to their polymeric counterparts. In this perspective, the article gives an overview about the inorganic material systems used for cell encapsulation, followed by reviewing the most important applications. The future may lay in a combination of the currently achieved biohybrid systems with additive manufacturing techniques. In a longer perspective, this would enable the direct printing of cell loaded bioreactor components. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  3. Core-shell-corona polymeric micelles as a versatile template for synthesis of inorganic hollow nanospheres.

    PubMed

    Sasidharan, Manickam; Nakashima, Kenichi

    2014-01-21

    Hollow, inorganic nanoscale capsules have many applications, from the delivery of encapsulated products for cosmetic and medicinal purposes to use as lightweight composite materials. Early methods for producing inorganic hollow nanospheres using hard templates suffered from low product yield and shell weakness upon template removal. In the past decade, researchers have turned to amphiphilic copolymers to synthesize hollow nanostructures and ordered mesoporous materials. Amphiphilic molecules self-assemble into well-defined nanostructures including spherical micelles. Micelles formed from simple, two-component AB diblock and ABA triblock copolymers, however, have been difficult to work with to construct inorganic hollow nanoparticles, because the corona of the micelle, which serves as the template for the shell, becomes unstable as it absorbs inorganic shell precursors, causing aggregates to form. Newly developed, three-component ABC triblock copolymers may solve this problem. They provide nanoassemblies with more diverse morphological and functional features than AB diblock and ABA triblock copolymers. Micelles formed from ABC triblock copolymers in selective solvents that dissolve only one or two of the blocks provide templates for these improved nanoassemblies. By manipulating individual polymer blocks, one can "encode" additional features at the molecular level. For instance, modifying the functional groups or substitution patterns of the blocks allows better morphological and size control. Insights into polymer self-assembly gained over years of work in our group have set the stage to systematically engineer inorganic spherical hollow nanoparticles using ABC triblock copolymers. In this Account, we report our recent progress in producing diverse, inorganic hollow spherical nanospheres from asymmetric triblock copolymeric micelles with core-shell-corona architecture as templates. We discuss three classes of polymeric micelles-with neutral, cationic, and anionic shell structures-that allow fabrication of a variety of hollow nanoparticles. Importantly, we synthesized all of these particles in water, avoiding use of hazardous organic solvents. We have designed the precursor of the inorganic material to be selectively sorbed into the shell domain, leaving the corona free from the inorganic precursors that would destabilize the micelle. The core, meanwhile, is the template for the formation of the hollow void. By rationally tailoring experimental parameters, we readily and selectively obtained a variety of hollow nanoparticles including silica, hybrid silicas, metal-oxides, metal-carbonates, metal-sulfates, metal-borates, and metal-phosphates. Finally, we highlight the state-of-the-art techniques we used to characterize these nanoparticles, and describe experiments that demonstrate the potential of these hollow particles in drug delivery, and as anode and cathode materials for lithium-ion batteries.

  4. Membranes with Surface-Enhanced Antifouling Properties for Water Purification

    PubMed Central

    Shahkaramipour, Nima; Tran, Thien N.; Ramanan, Sankara; Lin, Haiqing

    2017-01-01

    Membrane technology has emerged as an attractive approach for water purification, while mitigation of fouling is key to lower membrane operating costs. This article reviews various materials with antifouling properties that can be coated or grafted onto the membrane surface to improve the antifouling properties of the membranes and thus, retain high water permeance. These materials can be separated into three categories, hydrophilic materials, such as poly(ethylene glycol), polydopamine and zwitterions, hydrophobic materials, such as fluoropolymers, and amphiphilic materials. The states of water in these materials and the mechanisms for the antifouling properties are discussed. The corresponding approaches to coat or graft these materials on the membrane surface are reviewed, and the materials with promising performance are highlighted. PMID:28273869

  5. Membranes with Surface-Enhanced Antifouling Properties for Water Purification.

    PubMed

    Shahkaramipour, Nima; Tran, Thien N; Ramanan, Sankara; Lin, Haiqing

    2017-03-05

    Membrane technology has emerged as an attractive approach for water purification, while mitigation of fouling is key to lower membrane operating costs. This article reviews various materials with antifouling properties that can be coated or grafted onto the membrane surface to improve the antifouling properties of the membranes and thus, retain high water permeance. These materials can be separated into three categories, hydrophilic materials, such as poly(ethylene glycol), polydopamine and zwitterions, hydrophobic materials, such as fluoropolymers, and amphiphilic materials. The states of water in these materials and the mechanisms for the antifouling properties are discussed. The corresponding approaches to coat or graft these materials on the membrane surface are reviewed, and the materials with promising performance are highlighted.

  6. Effect of the oral administration homeopathic Arnica montana on mitochondrial oxidative stress.

    PubMed

    de Camargo, Ronaldo Antônio; da Costa, Ellen Dias; Catisti, Rosana

    2013-01-01

    To analyze the effect of homeopathic Arnica on mitochondrial oxidative stress induced by Ca(2+) plus inorganic phosphate and/or Fe(2+)-citrate-mediated lipid peroxidation through changes in oxygen consumption rates. Mitochondria were isolated by differential centrifugation from the livers of adult male Wistar rats which had been treated with Arnica montana 6cH, 12cH, 30cH or succussed 30% ethanol (control) for 21 days. In the presence of antimycin-A, electron transport chain inhibitor, as evidenced by antimycin-A insensitive O(2) consumption, Arnica inhibited lipid peroxidation of mitochondrial membranes. In oxidative stress conditions, in the presence of Ca(2+) and inorganic phosphate, animals receiving Arnica 30cH had a significant decrease in mitochondrial O(2) consumption compared to control animals. When administrated orally, Arnica 30cH protects against hepatic mitochondrial membrane permeabilization induced by Ca(2+) and/or Fe(2+)-citrate-mediated lipid peroxidation and fragmentation of proteins due to the attack by reactive oxygen species. Copyright © 2012 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

  7. Synthesis, Multinuclear NMR Characterization and Dynamic Property of Organic–Inorganic Hybrid Electrolyte Membrane Based on Alkoxysilane and Poly(oxyalkylene) Diamine

    PubMed Central

    Saikia, Diganta; Pan, Yu-Chi; Kao, Hsien-Ming

    2012-01-01

    Organic–inorganic hybrid electrolyte membranes based on poly(propylene glycol)-block-poly(ethylene glycol)-block-poly(propylene glycol) bis(2-aminopropyl ether) complexed with LiClO4 via the co-condensation of tetraethoxysilane (TEOS) and 3-(triethoxysilyl)propyl isocyanate have been prepared and characterized. A variety of techniques such as differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, alternating current (AC) impedance and solid-state nuclear magnetic resonance (NMR) spectroscopy are performed to elucidate the relationship between the structural and dynamic properties of the hybrid electrolyte and the ion mobility. A VTF (Vogel-Tamman-Fulcher)-like temperature dependence of ionic conductivity is observed for all the compositions studied, implying that the diffusion of charge carriers is assisted by the segmental motions of the polymer chains. A maximum ionic conductivity value of 5.3 × 10−5 Scm−1 is obtained at 30 °C. Solid-state NMR results provide a microscopic view of the effects of salt concentrations on the dynamic behavior of the polymer chains. PMID:24958176

  8. Method of making nanopatterns and nanostructures and nanopatterned functional oxide materials

    DOEpatents

    Dravid, Vinayak P; Donthu, Suresh K; Pan, Zixiao

    2014-02-11

    Method for nanopatterning of inorganic materials, such as ceramic (e.g. metal oxide) materials, and organic materials, such as polymer materials, on a variety of substrates to form nanopatterns and/or nanostructures with control of dimensions and location, all without the need for etching the materials and without the need for re-alignment between multiple patterning steps in forming nanostructures, such as heterostructures comprising multiple materials. The method involves patterning a resist-coated substrate using electron beam lithography, removing a portion of the resist to provide a patterned resist-coated substrate, and spin coating the patterned resist-coated substrate with a liquid precursor, such as a sol precursor, of the inorganic or organic material. The remaining resist is removed and the spin coated substrate is heated at an elevated temperature to crystallize the deposited precursor material.

  9. Recent advances in inorganic nanoparticle-based drug delivery systems.

    PubMed

    Murakami, Tatsuya; Tsuchida, Kunihiro

    2008-02-01

    Drug delivery systems, designed to enhance drug efficacy and reduce their adverse effects, have evolved accompanied by the development of novel materials. Nanotechnology is an emerging scientific area that has created a variety of intriguing inorganic nanoparticles. In this review, we focus on the feasibility of inorganic nanoparticles, including iron oxide nanoparticles, gold nanoparticles, fullerenes and carbon nanohorns, as drug carriers, and summarize recent advances in this field.

  10. Effects of inorganic ions on morphology of octacalcium phosphate grown on cation selective membrane at physiological temperature and pH in relation to enamel formation

    NASA Astrophysics Data System (ADS)

    Iijima, Mayumi; Moriwaki, Yutaka

    1989-05-01

    The crystal growth of octacalcium phosphate (OCP) is of particular interest, since there is a possibility that OCP is formed in the early stage of tooth enamel formation. In this study, the effects of CO2-3, Mg2+ and F-ions on the morphology of OCP were investigated in a membrane system, where a cation selective membrane was used to simulate amelogenesis. Reactions were carried out at pH 6.3, 6.5 and 6.8 for 3 days at 37°C. In most cases, these ions suppressed the crystal growth in the c-axis direction of OCP, particularly when they coexisted. The morphology of OCP crystal changed from ribbon-like to flake-like, depending on the inhibitory activity. The inhibitory activity, particularly that of F - ion, was suppressed at pH lower than pH 6.8. Antagonistic effect of Mg2+ and F-ion was observed at pH 6.5. In the case of F - ion, OCP crystals showed a unique pattern, which suggests hydrolysis of OCP and subsequent growth of apatite. These findings indicate that inorganic ions, particularly F - ion, influence the growth of OCP. Although CO2-3, Mg2+andF-ions coexisted, extended growth in the c-axis direction of OCP took place at pH 6.0.

  11. Use of reinforced inorganic cement materials for spark wire and drift chamber wire frames

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The results of a survey, materials test, and analysis study directed toward the development of an inorganic glass-fiber reinforced cement material for use in the construction of space qualified spark wire frames and drift chamber frames are presented. The purpose for this research was to evaluate the feasibility of using glass fiber reinforced cement (GFRC) for large dimensioned structural frames for supporting a number of precisely located spark wires in multiple planes. A survey of the current state of the art in fiber reinforced cement materials was made; material sample mixes were made and tested to determine their laboratory performances. Tests conducted on sample materials showed that compressive and flexural strengths of this material could approach values which would enable fabrication of structural spark wire frames.

  12. Room-temperature ductile inorganic semiconductor.

    PubMed

    Shi, Xun; Chen, Hongyi; Hao, Feng; Liu, Ruiheng; Wang, Tuo; Qiu, Pengfei; Burkhardt, Ulrich; Grin, Yuri; Chen, Lidong

    2018-05-01

    Ductility is common in metals and metal-based alloys, but is rarely observed in inorganic semiconductors and ceramic insulators. In particular, room-temperature ductile inorganic semiconductors were not known until now. Here, we report an inorganic α-Ag 2 S semiconductor that exhibits extraordinary metal-like ductility with high plastic deformation strains at room temperature. Analysis of the chemical bonding reveals systems of planes with relatively weak atomic interactions in the crystal structure. In combination with irregularly distributed silver-silver and sulfur-silver bonds due to the silver diffusion, they suppress the cleavage of the material, and thus result in unprecedented ductility. This work opens up the possibility of searching for ductile inorganic semiconductors/ceramics for flexible electronic devices.

  13. Room-temperature ductile inorganic semiconductor

    NASA Astrophysics Data System (ADS)

    Shi, Xun; Chen, Hongyi; Hao, Feng; Liu, Ruiheng; Wang, Tuo; Qiu, Pengfei; Burkhardt, Ulrich; Grin, Yuri; Chen, Lidong

    2018-05-01

    Ductility is common in metals and metal-based alloys, but is rarely observed in inorganic semiconductors and ceramic insulators. In particular, room-temperature ductile inorganic semiconductors were not known until now. Here, we report an inorganic α-Ag2S semiconductor that exhibits extraordinary metal-like ductility with high plastic deformation strains at room temperature. Analysis of the chemical bonding reveals systems of planes with relatively weak atomic interactions in the crystal structure. In combination with irregularly distributed silver-silver and sulfur-silver bonds due to the silver diffusion, they suppress the cleavage of the material, and thus result in unprecedented ductility. This work opens up the possibility of searching for ductile inorganic semiconductors/ceramics for flexible electronic devices.

  14. Development of Repair Materials for Avulsive Combat-Type Maxillofacial Injuries.

    DTIC Science & Technology

    1981-11-01

    sone. A sample of 0.2702 grams of the resulting corn- nitic acid. tsocitric acid, alpha - ketoglutaric acid. suc- position was shaped into the form of a...polylactic acid and inorganic materials such as calcium carbonate or calcium sulfate. The chemistry of the system proposed for development includes...acid and high molecular weight poly(propylene fumarate) were synthesized at Dynatech to be used as organic fillers. Inorganic fil- lers such as calcium

  15. The Features of Self-Assembling Organic Bilayers Important to the Formation of Anisotropic Inorganic Materials in Microgravity Conditions

    NASA Technical Reports Server (NTRS)

    Talham, Daniel R.; Adair, James H.

    1999-01-01

    There is a growing need for inorganic anisotropic particles in a variety of materials science applications. Structural, optical, and electrical properties can be greatly augmented by the fabrication of composite materials with anisotropic microstructures or with anisotropic particles uniformly dispersed in an isotropic matrix. Examples include structural composites, magnetic and optical recording media, photographic film, certain metal and ceramic alloys, and display technologies including flat panel displays. While considerable progress has been made toward developing an understanding of the synthesis of powders composed of monodispersed, spherical particles, these efforts have not been transferred to the synthesis of anisotropic nanoparticles. The major objective of the program is to develop a fundamental understanding of the growth of anisotropic particles at organic templates, with emphasis on the chemical and structural aspects of layered organic assemblies that contribute to the formation of anisotropic inorganic particles.

  16. Freestanding, heat resistant microporous film for use in energy storage devices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pekala, Richard W.; Cherukupalli, Srinivas; Waterhouse, Robert R.

    Preferred embodiments of a freestanding, heat resistant microporous polymer film (10) constructed for use in an energy storage device (70, 100) implements one or more of the following approaches to exhibit excellent high temperature mechanical and dimensional stability: incorporation into a porous polyolefin film of sufficiently high loading levels of inorganic or ceramic filler material (16) to maintain porosity (18) and achieve low thermal shrinkage; use of crosslinkable polyethylene to contribute to crosslinking the polymer matrix (14) in a highly inorganic material-filled polyolefin film; and heat treating or annealing of biaxially oriented, highly inorganic material-filled polyolefin film above the meltingmore » point temperature of the polymer matrix to reduce residual stress while maintaining high porosity. The freestanding, heat resistant microporous polymer film embodiments exhibit extremely low resistance, as evidenced by MacMullin numbers of less than 4.5.« less

  17. p-type Mesoscopic nickel oxide/organometallic perovskite heterojunction solar cells.

    PubMed

    Wang, Kuo-Chin; Jeng, Jun-Yuan; Shen, Po-Shen; Chang, Yu-Cheng; Diau, Eric Wei-Guang; Tsai, Cheng-Hung; Chao, Tzu-Yang; Hsu, Hsu-Cheng; Lin, Pei-Ying; Chen, Peter; Guo, Tzung-Fang; Wen, Ten-Chin

    2014-04-23

    In this article, we present a new paradigm for organometallic hybrid perovskite solar cell using NiO inorganic metal oxide nanocrystalline as p-type electrode material and realized the first mesoscopic NiO/perovskite/[6,6]-phenyl C61-butyric acid methyl ester (PC61BM) heterojunction photovoltaic device. The photo-induced transient absorption spectroscopy results verified that the architecture is an effective p-type sensitized junction, which is the first inorganic p-type, metal oxide contact material for perovskite-based solar cell. Power conversion efficiency of 9.51% was achieved under AM 1.5 G illumination, which significantly surpassed the reported conventional p-type dye-sensitized solar cells. The replacement of the organic hole transport materials by a p-type metal oxide has the advantages to provide robust device architecture for further development of all-inorganic perovskite-based thin-film solar cells and tandem photovoltaics.

  18. p-type Mesoscopic Nickel Oxide/Organometallic Perovskite Heterojunction Solar Cells

    PubMed Central

    Wang, Kuo-Chin; Jeng, Jun-Yuan; Shen, Po-Shen; Chang, Yu-Cheng; Diau, Eric Wei-Guang; Tsai, Cheng-Hung; Chao, Tzu-Yang; Hsu, Hsu-Cheng; Lin, Pei-Ying; Chen, Peter; Guo, Tzung-Fang; Wen, Ten-Chin

    2014-01-01

    In this article, we present a new paradigm for organometallic hybrid perovskite solar cell using NiO inorganic metal oxide nanocrystalline as p-type electrode material and realized the first mesoscopic NiO/perovskite/[6,6]-phenyl C61-butyric acid methyl ester (PC61BM) heterojunction photovoltaic device. The photo-induced transient absorption spectroscopy results verified that the architecture is an effective p-type sensitized junction, which is the first inorganic p-type, metal oxide contact material for perovskite-based solar cell. Power conversion efficiency of 9.51% was achieved under AM 1.5 G illumination, which significantly surpassed the reported conventional p-type dye-sensitized solar cells. The replacement of the organic hole transport materials by a p-type metal oxide has the advantages to provide robust device architecture for further development of all-inorganic perovskite-based thin-film solar cells and tandem photovoltaics. PMID:24755642

  19. The effects of temperature and salinity on phosphate levels in two euryhaline crustacean species

    NASA Astrophysics Data System (ADS)

    Spaargaren, D. H.; Richard, P.; Ceccaldi, H. J.

    Total phoshate, inorganic phosphate and organic (phospholipid) phosphate concentrations were determined in the blood of Carcinus maenas and in whole-animal homogenates of Penaeus japonicus acclimatized to various salinities and a high or a low temperature. In the blood of Carcinus, total and inorganic P concentrations range between 1.0 and 4.5 mmol · l -1; the amount of phospholipids is negligeable. The higher values were found at more extreme salinities. Low temperature is associated with low phosphate concentrations, particularly at intermediate salinities. Total P concentrations in Penaeus homogenates range between 10 and 60 mmol · 1 -1; phospholipid concentrations range between zero and 50 mmol · 1 -1. The higher values are again found at the extreme salinities. Inorganic P concentrations are almost constant — ca 10 mmol · 1 -1. No apparent effect of temperature on phosphate concentrations was observed. The results show clearly that osmotic stress influences severely the phosphate metabolism of the two species studied. Both species are able to accumulate phosphate at all experimental temperature/salinity combinations used, even when deprived of food. At extreme salinities, large quantities of phosphate are accumulated and converted to organic P compounds, most likely as phospholipids associated with the cell membranes. These effects of osmotic conditions in phosphate metabolism may offer an explanation for the effect of Ca ++ on membrane permeability as the regulation of both ions may be strongly interrelated, often under hormonal control.

  20. Microbial mediated retention/transformation of organic and inorganic materials in freshwater and marine ecosystems

    EPA Science Inventory

    Aquatic ecosystems are globally connected by hydrological and biogeochemical cycles. Microorganisms inhabiting aquatic ecosystems form the basis of food webs, mediate essential element cycles, decompose natural organic matter, transform inorganic nutrients and metals, and degrad...

  1. Polishing Step Purification of High-Strength Wastewaters by Nanofiltration and Reverse Osmosis

    PubMed Central

    Zhou, Jinxiang; Baker, Brian O.; Grimsley, Charles T.; Husson, Scott M.

    2016-01-01

    This article reports findings on the use of nanofiltration (NF) and reverse osmosis (RO) for secondary treatment of high-strength rendering facility wastewaters following an ultrafiltration step. These wastewaters present significant challenges to classical treatment technologies. Constant-pressure, direct-flow membrane filtration experiments were done to screen for flux and effluent water permeate quality of ten commercial NF and RO membranes. All membranes tested were effective in reducing total dissolved salts (TDS) and chemical oxygen demand (COD); however, only two membranes (Koch MPF-34 and Toray 70UB) gave sufficiently stable flux values to warrant longer term cross-flow filtration studies. Cross-flow flux measurements, scanning electron microscopy (SEM), X-ray dispersive spectroscopy (EDS), and attenuated total reflectance-Fourier-transform infrared spectroscopy (ATR-FTIR) indicated that both membranes were eventually fouled by organic and inorganic foulants; however, the Toray 70UB RO membrane yielded a capacity of 1600 L/m2 prior to cleaning. A preliminary economic analysis compared the estimated costs of energy and consumables for a dual-stage UF/RO membrane process and dissolved air floatation (DAF) and found membrane process costs could be less than about 40% of the current DAF process. PMID:26978407

  2. A review on polyamide thin film nanocomposite (TFN) membranes: History, applications, challenges and approaches.

    PubMed

    Lau, W J; Gray, Stephen; Matsuura, T; Emadzadeh, D; Chen, J Paul; Ismail, A F

    2015-09-01

    This review focuses on the development of polyamide (PA) thin film nanocomposite (TFN) membranes for various aqueous media-based separation processes such as nanofiltration, reverse osmosis and forward osmosis since the concept of TFN was introduced in year 2007. Although the total number of published TFN articles falls far short of the articles of the well-known thin film composite (TFC) membranes, its growth rate is significant, particularly since 2012. Generally, by incorporating an appropriate amount of nanofiller into a thin selective PA layer of a composite membrane, one could produce TFN membranes with enhanced separation characteristics as compared to the conventional TFC membrane. For certain cases, the resulting TFN membranes demonstrate not only excellent antifouling resistance and/or greater antibacterial effect, but also possibly overcome the trade-off effect between water permeability and solute selectivity. Furthermore, this review attempts to give the readers insights into the difficulties of incorporating inorganic nanomaterials into the organic PA layer whose thickness usually falls in a range of several-hundred nanometers. It is also intended to show new possible approaches to overcome these challenges in TFN membrane fabrication. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Chemistry of Mesoporous Organosilica in Nanotechnology: Molecularly Organic-Inorganic Hybridization into Frameworks.

    PubMed

    Chen, Yu; Shi, Jianlin

    2016-05-01

    Organic-inorganic hybrid materials aiming to combine the individual advantages of organic and inorganic components while overcoming their intrinsic drawbacks have shown great potential for future applications in broad fields. In particular, the integration of functional organic fragments into the framework of mesoporous silica to fabricate mesoporous organosilica materials has attracted great attention in the scientific community for decades. The development of such mesoporous organosilica materials has shifted from bulk materials to nanosized mesoporous organosilica nanoparticles (designated as MONs, in comparison with traditional mesoporous silica nanoparticles (MSNs)) and corresponding applications in nanoscience and nanotechnology. In this comprehensive review, the state-of-art progress of this important hybrid nanomaterial family is summarized, focusing on the structure/composition-performance relationship of MONs of well-defined morphology, nanostructure, and nanoparticulate dimension. The synthetic strategies and the corresponding mechanisms for the design and construction of MONs with varied morphologies, compositions, nanostructures, and functionalities are overviewed initially. Then, the following part specifically concentrates on their broad spectrum of applications in nanotechnology, mainly in nanomedicine, nanocatalysis, and nanofabrication. Finally, some critical issues, presenting challenges and the future development of MONs regarding the rational synthesis and applications in nanotechnology are summarized and discussed. It is highly expected that such a unique molecularly organic-inorganic nanohybrid family will find practical applications in nanotechnology, and promote the advances of this discipline regarding hybrid chemistry and materials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Structural direction of hybrid organic-inorganic materials: Synthesis of vanadium oxyfluoride, copper vanadate, and copper molybdate solid state materials through solvuthermal and solution methods

    NASA Astrophysics Data System (ADS)

    Deburgomaster, Paul

    The vast structural complexity of inorganic oxides with structure directing organocations, nitrogen containing ligands and organophosphonate ligands was explored. The hydrothermal reaction conditions utilized herein include the variables of temperature, pH, fill volume and stoichiometry. The systems studied included: (1) the complex materials rendered from reactions of organoamine cations on the structure of vanadium oxides, oxyfluorides and fluorides. As with other systems, the influence of the mineralizer HF was not limited to pH as fluorine incorporation was not uncommon. In specific cases this coincided with reduction of vanadium sites. (2) The copper-organonitrogen ligand/vanadium oxide/aromatic phosphonate system has been studied. The rigid aromatic di- and tri-phosphonate tethers have provided a series of materials which are structurally distinct from the previously investigated aliphatic series. The inclusion of copper-coordinated nitrogen bi- and tri-dentate ligands also provided structural diversity. Product composition was highly influenced by the HF/V ratio. A similar study was conducted with the ligand 1,4-carboxy-phenylphosphonic acid. (3) The preparation of a series of bimetallic organic-inorganic hybrid materials of the M(II)/VxOy/organonitrogen ligand class was further evidence of the utility of thermodynamically driven hydrothermal synthesis. (4) While decomposition of the spherical Keplerate molybdenum clusters is encountered under hydrothermal conditions, this highly soluble form of molybdate was investigated for the development of hybrid organic-inorganic room temperature solution synthesis.

  5. The crystal chemistry of inorganic metal borohydrides and their relation to metal oxides.

    PubMed

    Černý, Radovan; Schouwink, Pascal

    2015-12-01

    The crystal structures of inorganic homoleptic metal borohydrides are analysed with respect to their structural prototypes found amongst metal oxides in the inorganic databases such as Pearson's Crystal Data [Villars & Cenzual (2015). Pearson's Crystal Data. Crystal Structure Database for Inorganic Compounds, Release 2014/2015, ASM International, Materials Park, Ohio, USA]. The coordination polyhedra around the cations and the borohydride anion are determined, and constitute the basis of the structural systematics underlying metal borohydride chemistry in various frameworks and variants of ionic packing, including complex anions and the packing of neutral molecules in the crystal. Underlying nets are determined by topology analysis using the program TOPOS [Blatov (2006). IUCr CompComm. Newsl. 7, 4-38]. It is found that the Pauling rules for ionic crystals apply to all non-molecular borohydride crystal structures, and that the latter can often be derived by simple deformation of the close-packed anionic lattices c.c.p. and h.c.p., by partially removing anions and filling tetrahedral or octahedral sites. The deviation from an ideal close packing is facilitated in metal borohydrides with respect to the oxide due to geometrical and electronic considerations of the BH4(-) anion (tetrahedral shape, polarizability). This review on crystal chemistry of borohydrides and their similarity to oxides is a contribution which should serve materials engineers as a roadmap to design new materials, synthetic chemists in their search for promising compounds to be prepared, and materials scientists in understanding the properties of novel materials.

  6. Inorganic materials for bone repair or replacement applications.

    PubMed

    Hertz, Audrey; Bruce, Ian J

    2007-12-01

    In recent years, excipient systems have been used increasingly in biomedicine in reconstructive and replacement surgery, as bone cements, drug-delivery vehicles and contrast agents. Particularly, interest has been growing in the development and application of controlled pore inorganic ceramic materials for use in bone-replacement and bone-repair roles and, in this context, attention has been focused on calcium-phosphate, bioactive glasses and SiO2- and TiO2-based materials. It has been shown that inorganic materials that most closely mimic bone structure and surface chemistry most closely function best in bone replacement/repair and, in particular, if a substance possesses a macroporous structure (pores and interconnections >100 microm diameter), then cell infiltration, bone growth and vascularization can all be promoted. The surface roughness and micro/mesoporosity of a material have also been observed to significantly influence its ability to promote apatite nucleation and cell attachment significantly. Pores (where present) can also be packed with pharmaceuticals and biomolecules (e.g., bone morphogenetic proteins [BMPs], which can stimulate bone formation). Finally, the most bio-efficient - in terms of collagen formation and apatite nucleation - materials are those that are able to provide soluble mineralizing species (Si, Ca, PO(4)) at their implant sites and/or are doped or have been surface-activated with specific functional groups. This article presents the context and latest advances in the field of bone-repair materials, especially with respect to the development of bioactive glasses and micro/mesoporous and macroporous inorganic scaffolds. It deals with the possible methods of preparing porous pure/doped or functionalized silicas or their composites, the studies that have been undertaken to evaluate their abilities to act as bone repair scaffolds and also presents future directions for work in that context.

  7. Materials processing in space

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The feasibility and possible advantages of processing materials in a nongravitational field are considered. Areas of investigation include biomedical applications, the processing of inorganic materials, and flight programs and funding.

  8. Comparison of the biological NH3 removal characteristics among four inorganic packing materials.

    PubMed

    Hirai, M; Kamamoto, M; Yani, M; Shoda, M

    2001-01-01

    Four inorganic packing materials were evaluated in terms of their availability as a packing material of a packed tower deodorization apparatus (biofilter) from the viewpoints of biological NH3 removal characteristics and some physical properties. Porous ceramics (A), calcinated cristobalite (B), calcinated and formed obsidian (C), granulated and calculated soil (D) were used. The superiority of these packing materials determined based on the values of non-biological removal per unit weight or unit volume of packing material, complete removal capacity of NH3 per unit weight of packing material per day or unit volume of packing material per day and pressure drop of the packed bed was in the order of A approximately = C > B > or = D. Packing materials A and C with high porosity, maximum water content, and suitable mean pore diameter showed excellent removal capacity.

  9. Mixed ionic and electronic conducting ceramic membranes for hydrocarbon processing

    DOEpatents

    Van Calcar, Pamela; Mackay, Richard; Sammells, Anthony F.

    2002-01-01

    The invention relates to mixed phase materials for the preparation of catalytic membranes which exhibit ionic and electronic conduction and which exhibit improved mechanical strength compared to single phase ionic and electronic conducting materials. The mixed phase materials are useful for forming gas impermeable membranes either as dense ceramic membranes or as dense thin films coated onto porous substrates. The membranes and materials of this invention are useful in catalytic membrane reactors in a variety of applications including synthesis gas production. One or more crystalline second phases are present in the mixed phase material at a level sufficient to enhance the mechanical strength of the mixture to provide membranes for practical application in CMRs.

  10. Recent advances in porous nanoparticles for drug delivery in antitumoral applications: inorganic nanoparticles and nanoscale metal-organic frameworks.

    PubMed

    Baeza, Alejandro; Ruiz-Molina, Daniel; Vallet-Regí, María

    2017-06-01

    Nanotechnology has provided new tools for addressing unmet clinical situations, especially in the oncology field. The development of smart nanocarriers able to deliver chemotherapeutic agents specifically to the diseased cells and to release them in a controlled way has offered a paramount advantage over conventional therapy. Areas covered: Among the different types of nanoparticle that can be employed for this purpose, inorganic porous materials have received significant attention in the last decade due to their unique properties such as high loading capacity, chemical and physical robustness, low toxicity and easy and cheap production in the laboratory. This review discuss the recent advances performed in the application of porous inorganic and metal-organic materials for antitumoral therapy, paying special attention to the application of mesoporous silica, porous silicon and metal-organic nanoparticles. Expert opinion: The use of porous inorganic nanoparticles as drug carriers for cancer therapy has the potential to improve the life expectancy of the patients affected by this disease. However, much work is needed to overcome their drawbacks, which are aggravated by their hard nature, exploiting the advantages offered by highly the ordered pore network of these materials.

  11. Membrane Inlet Mass Spectrometry for Homeland Security and Forensic Applications

    NASA Astrophysics Data System (ADS)

    Giannoukos, Stamatios; Brkić, Boris; Taylor, Stephen; France, Neil

    2015-02-01

    A man-portable membrane inlet mass spectrometer has been built and tested to detect and monitor characteristic odors emitted from the human body and also from threat substances. In each case, a heated membrane sampling probe was used. During human scent monitoring experiments, data were obtained for inorganic gases and volatile organic compounds emitted from human breath and sweat in a confined space. Volatile emissions were detected from the human body at low ppb concentrations. Experiments with compounds associated with narcotics, explosives, and chemical warfare agents were conducted for a range of membrane types. Test compounds included methyl benzoate (odor signature of cocaine), piperidine (precursor in clandestine phencyclidine manufacturing processes), 2-nitrotoluene (breakdown product of TNT), cyclohexanone (volatile signature of plastic explosives), dimethyl methylphosphonate (used in sarin and soman nerve agent production), and 2-chloroethyl ethyl sulfide (simulant compound for sulfur mustard gas). Gas phase calibration experiments were performed allowing sub-ppb LOD to be established. The results showed excellent linearity versus concentration and rapid membrane response times.

  12. Membrane inlet mass spectrometry for homeland security and forensic applications.

    PubMed

    Giannoukos, Stamatios; Brkić, Boris; Taylor, Stephen; France, Neil

    2015-02-01

    A man-portable membrane inlet mass spectrometer has been built and tested to detect and monitor characteristic odors emitted from the human body and also from threat substances. In each case, a heated membrane sampling probe was used. During human scent monitoring experiments, data were obtained for inorganic gases and volatile organic compounds emitted from human breath and sweat in a confined space. Volatile emissions were detected from the human body at low ppb concentrations. Experiments with compounds associated with narcotics, explosives, and chemical warfare agents were conducted for a range of membrane types. Test compounds included methyl benzoate (odor signature of cocaine), piperidine (precursor in clandestine phencyclidine manufacturing processes), 2-nitrotoluene (breakdown product of TNT), cyclohexanone (volatile signature of plastic explosives), dimethyl methylphosphonate (used in sarin and soman nerve agent production), and 2-chloroethyl ethyl sulfide (simulant compound for sulfur mustard gas). Gas phase calibration experiments were performed allowing sub-ppb LOD to be established. The results showed excellent linearity versus concentration and rapid membrane response times.

  13. Source water quality shaping different fouling scenarios in a full-scale desalination plant at the Red Sea.

    PubMed

    Khan, Muhammad Tariq; Manes, Carmem-Lara de O; Aubry, Cyril; Croué, Jean-Philippe

    2013-02-01

    The complexity of Reverse Osmosis (RO) membrane fouling phenomenon has been widely studied and several factors influencing it have been reported by many researchers. This original study involves the investigation of two different fouling profiles produced at a seawater RO desalination plant installed on a floating mobile barge. The plant was moved along the coastline of the Red Sea in Saudi Arabia. The two locations where the barge was anchored showed different water quality. At the second location, two modules were harvested. One of the modules was pre-fouled by inorganics during plant operation at the previous site while the other was installed at the second site. Fouled membranes were subjected to a wide range of chemical and microbiological characterization procedures. Drastically different fouling patterns were observed in the two membranes which indicates the influence of source water quality on membrane surface modification and on fouling of RO membranes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Single-ion polymer electrolyte membranes enable lithium-ion batteries with a broad operating temperature range.

    PubMed

    Cai, Weiwei; Zhang, Yunfeng; Li, Jing; Sun, Yubao; Cheng, Hansong

    2014-04-01

    Conductive processes involving lithium ions are analyzed in detail from a mechanistic perspective, and demonstrate that single ion polymeric electrolyte (SIPE) membranes can be used in lithium-ion batteries with a wide operating temperature range (25-80 °C) through systematic optimization of electrodes and electrode/electrolyte interfaces, in sharp contrast to other batteries equipped with SIPE membranes that display appreciable operability only at elevated temperatures (>60 °C). The performance is comparable to that of batteries using liquid electrolyte of inorganic salt, and the batteries exhibit excellent cycle life and rate performance. This significant widening of battery operation temperatures coupled with the inherent flexibility and robustness of the SIPE membranes makes it possible to develop thin and flexible Li-ion batteries for a broad range of applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Investigations of perspective technologies, equipment and sanitary - hygienic means for Life-Support System of new generation

    NASA Astrophysics Data System (ADS)

    Shumilina, I. V.

    Creation of optimal sanitary - hygienic conditions allows to keep health and capacity of the crewmembers work at increase of space flight duration. There is a wide application experience of means, methods and equipment for sanitary - hygienic supply, which were developed and experimentally tested for space flights. However, about 800 kg personal hygiene means (napkins and towels are made with water and delivered with the Earth) are necessary for 3 crewmembers per one year. For long orbital and interplanetary flights (without an opportunity of stocks updating) it is necessary to increase a degree of Life-Support System isolation and optimization of goods turnover. Washing combined with water regeneration system is most perspective for sanitary - hygienic procedures. Therefore, creation of space equipment for washing with sanitary - hygienic water (SHW) regeneration system is especially important. The researches have shown, that to processes, which can be applied for SHW regeneration in space conditions and require insignificant quantity of additional materials (as against sorption), concern membrane methods (reverse osmosis, nanofiltration etc.). Two-step membrane unit for SHW regeneration recovered no less than 85 % of permeate with the organic and inorganic selectivity of 82-95 %. The tests of two-step membrane unit for SHW regeneration carried out on mock up solutions and real SHW, containing detergents really used in space flight conditions. The researches on a substantiation of an opportunity of clothing washing, clothing drying and the estimation of an opportunity of application of various detergents for clothing washing are urgent. The tests of water extraction technology from textile materials are carried out. Is established, that at conditional time of contact 1s, humidity of a leaving air flow from clothing drying unit comes nearer to 100 %. It is necessary to solve the problem for creation of Life-Support System of new generation for long-term space flight conditions in view of an opportunity of integration of technologies, equipment and sanitary - hygienic supply means.

  16. Inorganic polyphosphate in the yeast Saccharomyces cerevisiae with a mutation disturbing the function of vacuolar ATPase.

    PubMed

    Tomaschevsky, A A; Ryasanova, L P; Kulakovskaya, T V; Kulaev, I S

    2010-08-01

    A mutation in the vma2 gene disturbing V-ATPase function in the yeast Saccharomyces cerevisiae results in a five- and threefold decrease in inorganic polyphosphate content in the stationary and active phases of growth on glucose, respectively. The average polyphosphate chain length in the mutant cells is decreased. The mutation does not prevent polyphosphate utilization during cultivation in a phosphate-deficient medium and recovery of its level on reinoculation in complete medium after phosphate deficiency. The content of short chain acid-soluble polyphosphates is recovered first. It is supposed that these polyphosphates are less dependent on the electrochemical gradient on the vacuolar membrane.

  17. Ion conducting organic/inorganic hybrid polymers

    NASA Technical Reports Server (NTRS)

    Meador, Maryann B. (Inventor); Kinder, James D. (Inventor)

    2010-01-01

    This invention relates to a series of organic/inorganic hybrid polymers that are easy to fabricate into dimensionally stable films with good ion-conductivity over a wide range of temperatures for use in a variety of applications. The polymers are prepared by the reaction of amines, preferably diamines and mixtures thereof with monoamines with epoxy-functionalized alkoxysilanes. The products of the reaction are polymerized by hydrolysis of the alkoxysilane groups to produce an organic-containing silica network. Suitable functionality introduced into the amine and alkoxysilane groups produce solid polymeric membranes which conduct ions for use in fuel cells, high-performance solid state batteries, chemical sensors, electrochemical capacitors, electro-chromic windows or displays, analog memory devices and the like.

  18. Metal-organic framework templated synthesis of porous inorganic materials as novel sorbents

    DOEpatents

    Taylor-Pashow, Kathryn M. L.; Lin, Wenbin; Abney, Carter W.

    2017-03-21

    A novel metal-organic framework (MOF) templated process for the synthesis of highly porous inorganic sorbents for removing radionuclides, actinides, and heavy metals is disclosed. The highly porous nature of the MOFs leads to highly porous inorganic sorbents (such as oxides, phosphates, sulfides, etc) with accessible surface binding sites that are suitable for removing radionuclides from high level nuclear wastes, extracting uranium from acid mine drainage and seawater, and sequestering heavy metals from waste streams. In some cases, MOFs can be directly used for removing these metal ions as MOFs are converted to highly porous inorganic sorbents in situ.

  19. Nanocomposites Derived from Polymers and Inorganic Nanoparticles

    PubMed Central

    Jeon, In-Yup; Baek, Jong-Beom

    2010-01-01

    Polymers are considered to be good hosting matrices for composite materials because they can easily be tailored to yield a variety of bulk physical properties. Moreover, organic polymers generally have long-term stability and good processability. Inorganic nanoparticles possess outstanding optical, catalytic, electronic and magnetic properties, which are significantly different their bulk states. By combining the attractive functionalities of both components, nanocomposites derived from organic polymers and inorganic nanoparticles are expected to display synergistically improved properties. The potential applications of the resultant nanocomposites are various, e.g. automotive, aerospace, opto-electronics, etc. Here, we review recent progress in polymer-based inorganic nanoparticle composites.

  20. Inorganic dendrimers: recent advances for catalysis, nanomaterials, and nanomedicine.

    PubMed

    Caminade, Anne-Marie

    2016-10-07

    Dendrimers are hyperbranched polymers having a perfectly defined structure because they are synthesized step-by-step in an iterative fashion, and not by polymerization reactions. Some dendrimers are considered as inorganic, as they possess inorganic atoms at each branching point. Among numerous examples, two families of inorganic dendrimers have emerged as particularly promising: silicon-containing dendrimers, particularly carbosilanes, and phosphorus-containing dendrimers, particularly phosphorhydrazones. This tutorial review will display the main properties of both families of dendrimers in the fields of catalysis, materials and biology/nanomedicine. Emphasis will be put on the most recent and promising examples.

  1. Cloud condensation nuclei activity of aliphatic amine secondary aerosol

    USDA-ARS?s Scientific Manuscript database

    Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g. hydroxyl radical and nitrate radical). The resulting particle composition can contain both secondary organic aerosol (SOA) and inorganic salts. The fraction of organic to inorganic materials in the particulate ...

  2. IRIS Toxicological Review of Inorganic Arsenic (Preliminary Assessment Materials)

    EPA Science Inventory

    In April 2014, EPA released the draft literature searches and associated search strategies, evidence tables, and exposure response arrays for inorganic arsenic (iAs) to obtain input from stakeholders and the public prior to developing the draft IRIS assessment. Specifically, EPA ...

  3. 46 CFR 153.1045 - Inorganic acids.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Inorganic acids. 153.1045 Section 153.1045 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Operations Special Cargo Procedures...

  4. 46 CFR 153.1045 - Inorganic acids.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Inorganic acids. 153.1045 Section 153.1045 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Operations Special Cargo Procedures...

  5. 46 CFR 153.1045 - Inorganic acids.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Inorganic acids. 153.1045 Section 153.1045 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Operations Special Cargo Procedures...

  6. Acquisition of a High Performance Computer Cluster for Materials Research and Education

    DTIC Science & Technology

    2015-04-17

    separation in all-organic and hybrid organic- inorganic solar cells. The outcome of the project 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13...diffusion and interfacial charge separation in all-organic and hybrid organic- inorganic solar cells. The outcome of the project is the development...simulations to predict charge carrier mobilities, exciton diffusion and interfacial charge separation in all- organic and hybrid organic- inorganic solar

  7. Electrochemical sensing of heavy metal ions with inorganic, organic and bio-materials.

    PubMed

    Cui, Lin; Wu, Jie; Ju, Huangxian

    2015-01-15

    As heavy metal ions severely harm human health, it is important to develop simple, sensitive and accurate methods for their detection in environment and food. Electrochemical detection featured with short analytical time, low power cost, high sensitivity and easy adaptability for in-situ measurement is one of the most developed methods. This review introduces briefly the recent achievements in electrochemical sensing of heavy metal ions with inorganic, organic and bio-materials modified electrodes. In particular, the unique properties of inorganic nanomaterials, organic small molecules or their polymers, enzymes and nucleic acids for detection of heavy metal ions are highlighted. By employing some representative examples, the design and sensing mechanisms of these electrodes are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Exciton-Dominated Core-Level Absorption Spectra of Hybrid Organic-Inorganic Lead Halide Perovskites.

    PubMed

    Vorwerk, Christian; Hartmann, Claudia; Cocchi, Caterina; Sadoughi, Golnaz; Habisreutinger, Severin N; Félix, Roberto; Wilks, Regan G; Snaith, Henry J; Bär, Marcus; Draxl, Claudia

    2018-04-19

    In a combined theoretical and experimental work, we investigate X-ray absorption near-edge structure spectroscopy of the I L 3 and the Pb M 5 edges of the methylammonium lead iodide (MAPbI 3 ) hybrid inorganic-organic perovskite and its binary phase PbI 2 . The absorption onsets are dominated by bound excitons with sizable binding energies of a few hundred millielectronvolts and pronounced anisotropy. The spectra of both materials exhibit remarkable similarities, suggesting that the fingerprints of core excitations in MAPbI 3 are essentially given by its inorganic component, with negligible influence from the organic groups. The theoretical analysis complementing experimental observations provides the conceptual insights required for a full characterization of this complex material.

  9. Combinatorial synthesis of novel materials

    DOEpatents

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    1999-01-01

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  10. Combinatorial sythesis of organometallic materials

    DOEpatents

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    2002-07-16

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  11. Polymer arrays from the combinatorial synthesis of novel materials

    DOEpatents

    Schultz, Peter G.; Xiang, Xiao-Dong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong

    2004-09-21

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  12. Combinatorial synthesis of novel materials

    DOEpatents

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    2002-02-12

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  13. Combinatorial synthesis of novel materials

    DOEpatents

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    1999-12-21

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  14. Combinatorial synthesis of novel materials

    DOEpatents

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    2001-01-01

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  15. Preparation and screening of crystalline zeolite and hydrothermally-synthesized materials

    DOEpatents

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong; Wang, Kai-An

    2005-03-08

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  16. Field Verification Program (Aquatic Disposal): Comparison of Field and Laboratory Bioaccumulation of Organic and Inorganic Contaminants from Black Rock Harbor Dredged Material

    DTIC Science & Technology

    1988-05-01

    include poly- chlorinated biphenyls (PCBs) and related chlorinated pesticides of similar polarity in addition to the petroleum hydrocarbons . The...Ui It tILL (JV: FIELD VERIFICATION PROGRAM (AQUATIC DISPOSAL).’Wh TECHNICAL REPORT D-87-6 COMPARISON OF FIELD AND LABORATORY BIOACCUMULATION OF...Laboratory Bioaccumulation of Organic and Inorganic Contaminants from Black Rock Harbor Dredged Material 12 PERSONAL AUTHOR(S) Lake, James L.; Galloway

  17. Synthesis of porous inorganic hollow fibers without harmful solvents.

    PubMed

    Shukla, Sushumna; de Wit, Patrick; Luiten-Olieman, Mieke W J; Kappert, Emiel J; Nijmeijer, Arian; Benes, Nieck E

    2015-01-01

    A route for the fabrication of porous inorganic hollow fibers with high surface-area-to-volume ratio that avoids harmful solvents is presented. The approach is based on bio-ionic gelation of an aqueous mixture of inorganic particles and sodium alginate during wet spinning. In a subsequent thermal treatment, the bio-organic material is removed and the inorganic particles are sintered. The method is applicable to the fabrication of various inorganic fibers, including metals and ceramics. The route completely avoids the use of organic solvents, such as N-methyl-2-pyrrolidone, and additives associated with the currently used fiber fabrication methods. In addition, it inherently avoids the manifestation of so-called macro voids and allows the facile incorporation of additional metal oxides in the inorganic hollow fibers. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Wood-Based Nanocomposite Derived by in Situ Formation of Organic-Inorganic Hybrid Polymer within Wood via a Sol-Gel Method.

    PubMed

    Dong, Xiaoying; Zhuo, Xiao; Wei, Jie; Zhang, Gang; Li, Yongfeng

    2017-03-15

    Solid wood materials and wood-plastic composites as two kinds of lightweight materials are attracting great interest from academia and industry due to their green and recycling nature. However, the relatively lower specific strength limits their wider applications. In particular, solid wood is vulnerable to moisture and decay fungi in nature, resulting in its poor durability for effectively long-term utilization. Inspired from the porous structure of wood, we propose a new design to build a wood-based nanocomposite with higher specific strength and satisfactory durability by in situ generation of organic-inorganic hybrid polymer within wood via a sol-gel method. The derived composite has 50-1200% improvement of impact toughness, 56-192% improvement of tensile strength, and 110-291% improvement of flexural strength over those of typical wood-plastic composites, respectively; and even 34% improvement of specific tensile strength than that of 36A steel; 208% enhancement of hardness; and 156% enhancement of compression strength than those of compared solid wood, respectively; as well as significantly improved dimensional stability and decay resistance over those of untreated natural wood. Such materials could be potentially utilized as lightweight and high-strength materials for applications in construction and automotive industries. This method could be extended to constitute other inorganic nanomaterials for novel organic-inorganic hybrid polymer within wood.

  19. Universal fragment descriptors for predicting properties of inorganic crystals

    NASA Astrophysics Data System (ADS)

    Isayev, Olexandr; Oses, Corey; Toher, Cormac; Gossett, Eric; Curtarolo, Stefano; Tropsha, Alexander

    2017-06-01

    Although historically materials discovery has been driven by a laborious trial-and-error process, knowledge-driven materials design can now be enabled by the rational combination of Machine Learning methods and materials databases. Here, data from the AFLOW repository for ab initio calculations is combined with Quantitative Materials Structure-Property Relationship models to predict important properties: metal/insulator classification, band gap energy, bulk/shear moduli, Debye temperature and heat capacities. The prediction's accuracy compares well with the quality of the training data for virtually any stoichiometric inorganic crystalline material, reciprocating the available thermomechanical experimental data. The universality of the approach is attributed to the construction of the descriptors: Property-Labelled Materials Fragments. The representations require only minimal structural input allowing straightforward implementations of simple heuristic design rules.

  20. Universal fragment descriptors for predicting properties of inorganic crystals.

    PubMed

    Isayev, Olexandr; Oses, Corey; Toher, Cormac; Gossett, Eric; Curtarolo, Stefano; Tropsha, Alexander

    2017-06-05

    Although historically materials discovery has been driven by a laborious trial-and-error process, knowledge-driven materials design can now be enabled by the rational combination of Machine Learning methods and materials databases. Here, data from the AFLOW repository for ab initio calculations is combined with Quantitative Materials Structure-Property Relationship models to predict important properties: metal/insulator classification, band gap energy, bulk/shear moduli, Debye temperature and heat capacities. The prediction's accuracy compares well with the quality of the training data for virtually any stoichiometric inorganic crystalline material, reciprocating the available thermomechanical experimental data. The universality of the approach is attributed to the construction of the descriptors: Property-Labelled Materials Fragments. The representations require only minimal structural input allowing straightforward implementations of simple heuristic design rules.

Top