A bibliographical surveys of large-scale systems
NASA Technical Reports Server (NTRS)
Corliss, W. R.
1970-01-01
A limited, partly annotated bibliography was prepared on the subject of large-scale system control. Approximately 400 references are divided into thirteen application areas, such as large societal systems and large communication systems. A first-author index is provided.
Large scale preparation and crystallization of neuron-specific enolase.
Ishioka, N; Isobe, T; Kadoya, T; Okuyama, T; Nakajima, T
1984-03-01
A simple method has been developed for the large scale purification of neuron-specific enolase [EC 4.2.1.11]. The method consists of ammonium sulfate fractionation of brain extract, and two subsequent column chromatography steps on DEAE Sephadex A-50. The chromatography was performed on a short (25 cm height) and thick (8.5 cm inside diameter) column unit that was specially devised for the large scale preparation. The purified enolase was crystallized in 0.05 M imidazole-HCl buffer containing 1.6 M ammonium sulfate (pH 6.39), with a yield of 0.9 g/kg of bovine brain tissue.
Zhu, Yuyang; Yan, Maomao; Lasanajak, Yi; Smith, David F; Song, Xuezheng
2018-07-15
Despite the important advances in chemical and chemoenzymatic synthesis of glycans, access to large quantities of complex natural glycans remains a major impediment to progress in Glycoscience. Here we report a large-scale preparation of N-glycans from a kilogram of commercial soy proteins using oxidative release of natural glycans (ORNG). The high mannose and paucimannose N-glycans were labeled with a fluorescent tag and purified by size exclusion and multidimensional preparative HPLC. Side products are identified and potential mechanisms for the oxidative release of natural N-glycans from glycoproteins are proposed. This study demonstrates the potential for using the ORNG approach as a complementary route to synthetic approaches for the preparation of multi-milligram quantities of biomedically relevant complex glycans. Copyright © 2018 Elsevier Ltd. All rights reserved.
Sebaaly, Carine; Greige-Gerges, Hélène; Agusti, Géraldine; Fessi, Hatem; Charcosset, Catherine
2016-01-01
Based on our previous study where optimal conditions were defined to encapsulate clove essential oil (CEO) into liposomes at laboratory scale, we scaled-up the preparation of CEO and eugenol (Eug)-loaded liposomes using a membrane contactor (600 mL) and a pilot plant (3 L) based on the principle of ethanol injection method, both equipped with a Shirasu Porous Glass membrane for injection of the organic phase into the aqueous phase. Homogenous, stable, nanometric-sized and multilamellar liposomes with high phospholipid, Eug loading rates and encapsulation efficiency of CEO components were obtained. Saturation of phospholipids and drug concentration in the organic phase may control the liposome stability. Liposomes loaded with other hydrophobic volatile compounds could be prepared at large scale using the ethanol injection method and a membrane for injection.
Large-scale Eucalyptus energy farms and power cogeneration
Robert C. Noroña
1983-01-01
A thorough evaluation of all factors possibly affecting a large-scale planting of eucalyptus is foremost in determining the cost effectiveness of the planned operation. Seven basic areas of concern must be analyzed:1. Species Selection 2. Site Preparation 3. Planting 4. Weed Control 5....
Ito, Y; Zhang, T Y
1988-11-25
A preparative capability of the present cross-axis synchronous flow-through coil planet centrifuge was demonstrated with 0.5 cm I.D. multilayer coils. Results of the model studies with short coils indicated that the optimal separations are obtained at low revolutional speeds of 100-200 rpm in both central and lateral coil positions. Preparative separations were successfully performed on 2.5-10 g quantities of test samples in a pair of multilayer coils connected in series with a total capacity of 2.5 l. The sample loading capacity will be scaled up in several folds by increasing the column width.
Wei, Binnian; Feng, June; Rehmani, Imran J; Miller, Sharyn; McGuffey, James E; Blount, Benjamin C; Wang, Lanqing
2014-09-25
Most sample preparation methods characteristically involve intensive and repetitive labor, which is inefficient when preparing large numbers of samples from population-scale studies. This study presents a robotic system designed to meet the sampling requirements for large population-scale studies. Using this robotic system, we developed and validated a method to simultaneously measure urinary anatabine, anabasine, nicotine and seven major nicotine metabolites: 4-Hydroxy-4-(3-pyridyl)butanoic acid, cotinine-N-oxide, nicotine-N-oxide, trans-3'-hydroxycotinine, norcotinine, cotinine and nornicotine. We analyzed robotically prepared samples using high-performance liquid chromatography (HPLC) coupled with triple quadrupole mass spectrometry in positive electrospray ionization mode using scheduled multiple reaction monitoring (sMRM) with a total runtime of 8.5 min. The optimized procedure was able to deliver linear analyte responses over a broad range of concentrations. Responses of urine-based calibrators delivered coefficients of determination (R(2)) of >0.995. Sample preparation recovery was generally higher than 80%. The robotic system was able to prepare four 96-well plate (384 urine samples) per day, and the overall method afforded an accuracy range of 92-115%, and an imprecision of <15.0% on average. The validation results demonstrate that the method is accurate, precise, sensitive, robust, and most significantly labor-saving for sample preparation, making it efficient and practical for routine measurements in large population-scale studies such as the National Health and Nutrition Examination Survey (NHANES) and the Population Assessment of Tobacco and Health (PATH) study. Published by Elsevier B.V.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harringa, J.L.; Cook, B.A.
1996-06-01
Improvements to state-of-the-art Si{sub 80}Ge{sub 20} thermoelectric alloys have been observed in laboratory-scale samples by the powder metallurgy techniques of mechanical alloying and hot pressing. Incorporating these improvements in large scale compacts for the production of thermoelectric generator elements is the next step in achieving higher efficiency RTGs. This paper discusses consolidation of large quantities of mechanically alloyed powders into production size compacts. Differences in thermoelectric properties are noted between the compacts prepared by the standard technique of hot uniaxial pressing and hot isostatic pressing. Most significant is the difference in carrier concentration between the alloys prepared by the twomore » consolidation techniques.« less
Fire management over large landscapes: a hierarchical approach
Kenneth G. Boykin
2008-01-01
Management planning for fires becomes increasingly difficult as scale increases. Stratification provides land managers with multiple scales in which to prepare plans. Using statistical techniques, Geographic Information Systems (GIS), and meetings with land managers, we divided a large landscape of over 2 million acres (White Sands Missile Range) into parcels useful in...
Overview of Opportunities for Co-Location of Solar Energy Technologies and Vegetation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Macknick, Jordan; Beatty, Brenda; Hill, Graham
2013-12-01
Large-scale solar facilities have the potential to contribute significantly to national electricity production. Many solar installations are large-scale or utility-scale, with a capacity over 1 MW and connected directly to the electric grid. Large-scale solar facilities offer an opportunity to achieve economies of scale in solar deployment, yet there have been concerns about the amount of land required for solar projects and the impact of solar projects on local habitat. During the site preparation phase for utility-scale solar facilities, developers often grade land and remove all vegetation to minimize installation and operational costs, prevent plants from shading panels, and minimizemore » potential fire or wildlife risks. However, the common site preparation practice of removing vegetation can be avoided in certain circumstances, and there have been successful examples where solar facilities have been co-located with agricultural operations or have native vegetation growing beneath the panels. In this study we outline some of the impacts that large-scale solar facilities can have on the local environment, provide examples of installations where impacts have been minimized through co-location with vegetation, characterize the types of co-location, and give an overview of the potential benefits from co-location of solar energy projects and vegetation. The varieties of co-location can be replicated or modified for site-specific use at other solar energy installations around the world. We conclude with opportunities to improve upon our understanding of ways to reduce the environmental impacts of large-scale solar installations.« less
Large-scale preparation of plasmid DNA.
Heilig, J S; Elbing, K L; Brent, R
2001-05-01
Although the need for large quantities of plasmid DNA has diminished as techniques for manipulating small quantities of DNA have improved, occasionally large amounts of high-quality plasmid DNA are desired. This unit describes the preparation of milligram quantities of highly purified plasmid DNA. The first part of the unit describes three methods for preparing crude lysates enriched in plasmid DNA from bacterial cells grown in liquid culture: alkaline lysis, boiling, and Triton lysis. The second part describes four methods for purifying plasmid DNA in such lysates away from contaminating RNA and protein: CsCl/ethidium bromide density gradient centrifugation, polyethylene glycol (PEG) precipitation, anion-exchange chromatography, and size-exclusion chromatography.
Discovery of Newer Therapeutic Leads for Prostate Cancer
2009-06-01
promising plant extracts and then prepare large-scale quantities of the plant extracts using supercritical fluid extraction techniques and use this...quantities of the plant extracts using supercritical fluid extraction techniques. Large scale plant collections were conducted for 14 of the top 20...material for bioassay-guided fractionation of the biologically active constituents using modern chromatography techniques. The chemical structures of
ERIC Educational Resources Information Center
Abramovich, Samuel; Schunn, Christian
2012-01-01
Ultra-large-scale interactive systems on the Internet have begun to change how teachers prepare for instruction, particularly in regards to resource selection. Consequently, it is important to look at how teachers are currently selecting resources beyond content or keyword search. We conducted a two-part observational study of an existing popular…
Large-scale uniform bilayer graphene prepared by vacuum graphitization of 6H-SiC(0001) substrates
NASA Astrophysics Data System (ADS)
Wang, Qingyan; Zhang, Wenhao; Wang, Lili; He, Ke; Ma, Xucun; Xue, Qikun
2013-03-01
We report on the preparation of large-scale uniform bilayer graphenes on nominally flat Si-polar 6H-SiC(0001) substrates by flash annealing in ultrahigh vacuum. The resulting graphenes have a single thickness of one bilayer and consist of regular terraces separated by the triple SiC bilayer steps on the 6H-SiC(0001) substrates. In situ scanning tunneling microscopy reveals that suppression of pit formation on terraces and uniformity of SiC decomposition at step edges are the key factors to the uniform thickness. By studying the surface morphologies prepared under different annealing rates, it is found that the annealing rate is directly related to SiC decomposition, diffusion of the released Si/C atoms and strain relaxation, which together determine the final step structure and density of defects.
Large-scale uniform bilayer graphene prepared by vacuum graphitization of 6H-SiC(0001) substrates.
Wang, Qingyan; Zhang, Wenhao; Wang, Lili; He, Ke; Ma, Xucun; Xue, Qikun
2013-03-06
We report on the preparation of large-scale uniform bilayer graphenes on nominally flat Si-polar 6H-SiC(0001) substrates by flash annealing in ultrahigh vacuum. The resulting graphenes have a single thickness of one bilayer and consist of regular terraces separated by the triple SiC bilayer steps on the 6H-SiC(0001) substrates. In situ scanning tunneling microscopy reveals that suppression of pit formation on terraces and uniformity of SiC decomposition at step edges are the key factors to the uniform thickness. By studying the surface morphologies prepared under different annealing rates, it is found that the annealing rate is directly related to SiC decomposition, diffusion of the released Si/C atoms and strain relaxation, which together determine the final step structure and density of defects.
Schmidt, Olga; Hausmann, Axel; Cancian de Araujo, Bruno; Sutrisno, Hari; Peggie, Djunijanti; Schmidt, Stefan
2017-01-01
Here we present a general collecting and preparation protocol for DNA barcoding of Lepidoptera as part of large-scale rapid biodiversity assessment projects, and a comparison with alternative preserving and vouchering methods. About 98% of the sequenced specimens processed using the present collecting and preparation protocol yielded sequences with more than 500 base pairs. The study is based on the first outcomes of the Indonesian Biodiversity Discovery and Information System (IndoBioSys). IndoBioSys is a German-Indonesian research project that is conducted by the Museum für Naturkunde in Berlin and the Zoologische Staatssammlung München, in close cooperation with the Research Center for Biology - Indonesian Institute of Sciences (RCB-LIPI, Bogor).
Large scale synthesis of nanostructured zirconia-based compounds from freeze-dried precursors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gomez, A.; Villanueva, R.; Vie, D.
2013-01-15
Nanocrystalline zirconia powders have been obtained at the multigram scale by thermal decomposition of precursors resulting from the freeze-drying of aqueous acetic solutions. This technique has equally made possible to synthesize a variety of nanostructured yttria or scandia doped zirconia compositions. SEM images, as well as the analysis of the XRD patterns, show the nanoparticulated character of those solids obtained at low temperature, with typical particle size in the 10-15 nm range when prepared at 673 K. The presence of the monoclinic, the tetragonal or both phases depends on the temperature of the thermal treatment, the doping concentration and themore » nature of the dopant. In addition, Rietveld refinement of the XRD profiles of selected samples allows detecting the coexistence of the tetragonal and the cubic phases for high doping concentration and high thermal treatment temperatures. Raman experiments suggest the presence of both phases also at relatively low treatment temperatures. - Graphical abstract: Zr{sub 1-x}A{sub x}O{sub 2-x/2} (A=Y, Sc; 0{<=}x{<=}0.12) solid solutions have been prepared as nanostructured powders by thermal decomposition of precursors obtained by freeze-drying, and this synthetic procedure has been scaled up to the 100 g scale. Highlights: Black-Right-Pointing-Pointer Zr{sub 1-x}A{sub x}O{sub 2-x/2} (A=Y, Sc; 0{<=}x{<=}0.12) solid solutions have been prepared as nanostructured powders. Black-Right-Pointing-Pointer The synthetic method involves the thermal decomposition of precursors obtained by freeze-drying. Black-Right-Pointing-Pointer The temperature of the thermal treatment controls particle sizes. Black-Right-Pointing-Pointer The preparation procedure has been scaled up to the 100 g scale. Black-Right-Pointing-Pointer This method is appropriate for the large-scale industrial preparation of multimetallic systems.« less
Managing Materials and Wastes for Homeland Security Incidents
To provide information on waste management planning and preparedness before a homeland security incident, including preparing for the large amounts of waste that would need to be managed when an incident occurs, such as a large-scale natural disaster.
Hausmann, Axel; Cancian de Araujo, Bruno; Sutrisno, Hari; Peggie, Djunijanti; Schmidt, Stefan
2017-01-01
Abstract Here we present a general collecting and preparation protocol for DNA barcoding of Lepidoptera as part of large-scale rapid biodiversity assessment projects, and a comparison with alternative preserving and vouchering methods. About 98% of the sequenced specimens processed using the present collecting and preparation protocol yielded sequences with more than 500 base pairs. The study is based on the first outcomes of the Indonesian Biodiversity Discovery and Information System (IndoBioSys). IndoBioSys is a German-Indonesian research project that is conducted by the Museum für Naturkunde in Berlin and the Zoologische Staatssammlung München, in close cooperation with the Research Center for Biology – Indonesian Institute of Sciences (RCB-LIPI, Bogor). PMID:29134041
Use of Nanostructures in Fabrication of Large Scale Electrochemical Film
NASA Astrophysics Data System (ADS)
Chen, Chien Chon; Chen, Shih Hsun; Shyu, Sheang Wen; Hsieh, Sheng Jen
Control of electrochemical parameters when preparing small-scale samples for academic research is not difficult. In mass production environments, however, maintenance of constant current density and temperature become a critical issue. This article describes the design of several molds for large work pieces. These molds were designed to maintain constant current density and to facilitate the occurrence of electrochemical reactions in designated areas. Large-area thin films with fine nanostructure were successfully prepared using the designed electrochemical molds and containers. In addition, current density and temperature could be controlled well. This electrochemical system has been verified in many experimental operations, including etching of Al surfaces; electro-polishing of Al, Ti and stainless steel; and fabrication of anodic alumina oxide (AAO), Ti-TiO2 interference membrane, TiO2 nanotubes, AAO-TiO2 nanotubes, Ni nanowires and porous tungsten
Generating multi-photon W-like states for perfect quantum teleportation and superdense coding
NASA Astrophysics Data System (ADS)
Li, Ke; Kong, Fan-Zhen; Yang, Ming; Ozaydin, Fatih; Yang, Qing; Cao, Zhuo-Liang
2016-08-01
An interesting aspect of multipartite entanglement is that for perfect teleportation and superdense coding, not the maximally entangled W states but a special class of non-maximally entangled W-like states are required. Therefore, efficient preparation of such W-like states is of great importance in quantum communications, which has not been studied as much as the preparation of W states. In this paper, we propose a simple optical scheme for efficient preparation of large-scale polarization-based entangled W-like states by fusing two W-like states or expanding a W-like state with an ancilla photon. Our scheme can also generate large-scale W states by fusing or expanding W or even W-like states. The cost analysis shows that in generating large-scale W states, the fusion mechanism achieves a higher efficiency with non-maximally entangled W-like states than maximally entangled W states. Our scheme can also start fusion or expansion with Bell states, and it is composed of a polarization-dependent beam splitter, two polarizing beam splitters and photon detectors. Requiring no ancilla photon or controlled gate to operate, our scheme can be realized with the current photonics technology and we believe it enable advances in quantum teleportation and superdense coding in multipartite settings.
Zhang, Hongcai; Yun, Sanyue; Song, Lingling; Zhang, Yiwen; Zhao, Yanyun
2017-03-01
The crustacean shells of crabs and shrimps produces quantities of by-products, leading to seriously environmental pollution and human health problems during industrial processing, yet they turned into high-value useful products, such as chitin and chitosan. To prepare them under large-scale submerged fermentation level, shrimp shell powders (SSPs) was fermented by successive three-step fermentation of Serratia marcescens B742, Lactobacillus plantarum ATCC 8014 and Rhizopus japonicus M193 to extract chitin and chitosan based on previously optimal conditions. Moreover, the key parameters was investigated to monitor the changes of resulted products during fermentation process. The results showed that the yield of prepared chitin and chitosan reached 21.35 and 13.11% with the recovery rate of 74.67 and 63.42%, respectively. The degree of deacetylation (DDA) and molecular mass (MM) of produced chitosan were 81.23% and 512.06kDa, respectively. The obtained chitin and chitosan was characterized using Fourier transform infrared spectrometer (FT-IR) and X-ray diffraction (XRD) analysis. The established microbial fermentation method can be applied for the industrial large-scale production of chitin and chitosan, while the use of chemical reagents was significantly reduced. Copyright © 2016 Elsevier B.V. All rights reserved.
Large-scale production and properties of human plasma-derived activated Factor VII concentrate.
Tomokiyo, K; Yano, H; Imamura, M; Nakano, Y; Nakagaki, T; Ogata, Y; Terano, T; Miyamoto, S; Funatsu, A
2003-01-01
An activated Factor VII (FVIIa) concentrate, prepared from human plasma on a large scale, has to date not been available for clinical use for haemophiliacs with antibodies against FVIII and FIX. In the present study, we attempted to establish a large-scale manufacturing process to obtain plasma-derived FVIIa concentrate with high recovery and safety, and to characterize its biochemical and biological properties. FVII was purified from human cryoprecipitate-poor plasma, by a combination of anion exchange and immunoaffinity chromatography, using Ca2+-dependent anti-FVII monoclonal antibody. To activate FVII, a FVII preparation that was nanofiltered using a Bemberg Microporous Membrane-15 nm was partially converted to FVIIa by autoactivation on an anion-exchange resin. The residual FVII in the FVII and FVIIa mixture was completely activated by further incubating the mixture in the presence of Ca2+ for 18 h at 10 degrees C, without any additional activators. For preparation of the FVIIa concentrate, after dialysis of FVIIa against 20 mm citrate, pH 6.9, containing 13 mm glycine and 240 mm NaCl, the FVIIa preparation was supplemented with 2.5% human albumin (which was first pasteurized at 60 degrees C for 10 h) and lyophilized in vials. To inactivate viruses contaminating the FVIIa concentrate, the lyophilized product was further heated at 65 degrees C for 96 h in a water bath. Total recovery of FVII from 15 000 l of plasma was approximately 40%, and the FVII preparation was fully converted to FVIIa with trace amounts of degraded products (FVIIabeta and FVIIagamma). The specific activity of the FVIIa was approximately 40 U/ micro g. Furthermore, virus-spiking tests demonstrated that immunoaffinity chromatography, nanofiltration and dry-heating effectively removed and inactivated the spiked viruses in the FVIIa. These results indicated that the FVIIa concentrate had both high specific activity and safety. We established a large-scale manufacturing process of human plasma-derived FVIIa concentrate with a high yield, making it possible to provide sufficient FVIIa concentrate for use in haemophiliacs with inhibitory antibodies.
2010-04-01
Factors of Child Abuse in A Large Survey Sample. International FamilyViolence and Child Victimization Research Conference. Portsmouth, New...manuscript in preparation). Physical child abuse in a large-scale survey of the U.S. Air Force: Risk and promotive factors. Slep, A. M. S., Snarr, J...D., Heyman, R. E., & Foran, H. M. (manuscript in preparation). Risk and promotive factors for emotional child abuse among active duty U.S. Air
2001-05-01
isolates could retain gp120 in an oligomer. A large scale purification scheme was developed using lentil lectin affinity and size exclusion...34 e. Western blot analysis……………………………………………… 35 f. Large scale protein expression and purification…………………... 35 g. Metabolic labeling, size...isolate HIV-1 Env………... 60 c. Large scale antigen preparation and analysis……………………… 67 d. Cleaved, soluble crosslinked primary isolate Env binds
Lou, Zhengsong; He, Minglong; Wang, Ruikun; Qin, Weiwei; Zhao, Dejian; Chen, Changle
2014-02-17
Sub-micrometer-sized magnesium ferrite spheres consisting of uniform small particles have been prepared using a facile, large-scale solid-state reaction employing a molten salt technique. Extensive structural characterization of the as-prepared samples has been performed using scanning electron microscope, transmission electron microscopy, high-resolution transmission electron microscopy, selected area electron diffraction, and X-ray diffraction. The yield of the magnesium ferrite sub-micrometer spheres is up to 90%, and these sub-micrometer spheres are made up of square and rectangular nanosheets. The magnetic properties of magnesium ferrite sub-micrometer spheres are investigated, and the magnetization saturation value is about 24.96 emu/g. Moreover, the possible growth mechanism is proposed based on the experimental results.
Advances in the manufacture of MIP nanoparticles.
Poma, Alessandro; Turner, Anthony P F; Piletsky, Sergey A
2010-12-01
Molecularly imprinted polymers (MIPs) are prepared by creating a three-dimensional polymeric matrix around a template molecule. After the matrix is removed, complementary cavities with respect to shape and functional groups remain. MIPs have been produced for applications in in vitro diagnostics, therapeutics and separations. However, this promising technology still lacks widespread application because of issues related to large-scale production and optimization of the synthesis. Recent developments in the area of MIP nanoparticles might offer solutions to several problems associated with performance and application. This review discusses various approaches used in the preparation of MIP nanoparticles, focusing in particular on the issues associated with large-scale manufacture and implications for the performance of synthesized nanomaterials. Copyright © 2010 Elsevier Ltd. All rights reserved.
Students' Views of A-Level Mathematics as Preparation for Degree-Level Economics
ERIC Educational Resources Information Center
Darlington, Ellie; Bowyer, Jessica
2017-01-01
As part of a large-scale survey of over 4000 undergraduates at British universities, 238 economics students reported on their experiences of studying post-compulsory secondary mathematics qualifications (A-levels) and the preparation they provided for their degrees. Participants were positive about their experience of post-compulsory mathematics…
ERIC Educational Resources Information Center
Bowyer, Jessica; Darlington, Ellie
2018-01-01
This article reports on data from a large-scale study investigating students' mathematical transitions to higher education. Three hundred and seventy-one undergraduate bioscientists were surveyed in order to investigate their perceptions and experiences of studying post-compulsory mathematics, as preparation for the mathematics elements of their…
Xu, Qingsong; Huang, Tong; Li, Shanlong; Li, Ke; Li, Chuanlong; Liu, Yannan; Wang, Yuling; Yu, Chunyang; Zhou, Yongfeng
2018-05-09
Hierarchical solution self-assembly has nowadays become an important biomimetic method to prepare highly complex and multifunctional supramolecular structures. However, despites the great progress, it is still highly challenging to prepare hierarchical self-assemblies in a large scale since the self-assembly processes are generally performed at high dilution. Herein, we report an emulsion-assisted polymerization-induced self-assembly (EAPISA) method with the advantages of in-situ self-assembly process, scalable preparation and facile functionalization to prepare hierarchical multiscale sea urchin-like aggregates (SUAs). It also extends horizons of PISA in monomers and in polymerization method. The obtained SUAs from amphiphilic alternating copolymers represent a novel self-assembled structure with micron-sized rattan ball-like capsule (RBC) acting as the hollow core body and radiating nanotubes tens of micrometers in length as the hollow spines. They can effectively capture model proteins at an ultra-low concentration (≈10 nM) after functionalized with amino groups through click copolymerization. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
An improved method for large-scale preparation of negatively and positively supercoiled plasmid DNA.
Barth, Marita; Dederich, Debra; Dedon, Peter
2009-07-01
A rigorous understanding of the biological function of superhelical tension in cellular DNA requires the development of new tools and model systems for study. To this end, an ethidium bromide[#x02013]free method has been developed to prepare large quantities of either negatively or positively super-coiled plasmid DNA. The method is based upon the known effects of ionic strength on the direction of binding of DNA to an archaeal histone, rHMfB, with low and high salt concentrations leading to positive and negative DNA supercoiling, respectively. In addition to fully optimized conditions for large-scale (>500 microg) supercoiling reactions, the method is advantageous in that it avoids the use of mutagenic ethidium bromide, is applicable to chemically modified plasmid DNA substrates, and produces both positively and negatively supercoiled DNA using a single set of reagents.
A mesostructured Y zeolite as a superior FCC catalyst--lab to refinery.
García-Martínez, Javier; Li, Kunhao; Krishnaiah, Gautham
2012-12-18
A mesostructured Y zeolite was prepared by a surfactant-templated process at the commercial scale and tested in a refinery, showing superior hydrothermal stability and catalytic cracking selectivity, which demonstrates, for the first time, the promising future of mesoporous zeolites in large scale industrial applications.
The continuous large-scale preparation of several 1-methylimidazole based ionic liquids was carried out using a Spinning Tube-in-Tube (STT) reactor (manufactured by Kreido Laboratories). This reactor, which embodies and facilitates the use of Green Chemistry principles and Proce...
RNA–protein binding kinetics in an automated microfluidic reactor
Ridgeway, William K.; Seitaridou, Effrosyni; Phillips, Rob; Williamson, James R.
2009-01-01
Microfluidic chips can automate biochemical assays on the nanoliter scale, which is of considerable utility for RNA–protein binding reactions that would otherwise require large quantities of proteins. Unfortunately, complex reactions involving multiple reactants cannot be prepared in current microfluidic mixer designs, nor is investigation of long-time scale reactions possible. Here, a microfluidic ‘Riboreactor’ has been designed and constructed to facilitate the study of kinetics of RNA–protein complex formation over long time scales. With computer automation, the reactor can prepare binding reactions from any combination of eight reagents, and is optimized to monitor long reaction times. By integrating a two-photon microscope into the microfluidic platform, 5-nl reactions can be observed for longer than 1000 s with single-molecule sensitivity and negligible photobleaching. Using the Riboreactor, RNA–protein binding reactions with a fragment of the bacterial 30S ribosome were prepared in a fully automated fashion and binding rates were consistent with rates obtained from conventional assays. The microfluidic chip successfully combines automation, low sample consumption, ultra-sensitive fluorescence detection and a high degree of reproducibility. The chip should be able to probe complex reaction networks describing the assembly of large multicomponent RNPs such as the ribosome. PMID:19759214
Guide for preparing active solar heating systems operation and maintenance manuals
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1991-01-01
This book presents a systematic and standardized approach to the preparation of operation and maintenance manuals for active solar heating systems. Provides an industry consensus of the best operating and maintenance procedures for large commercial-scale solar service water and space heating systems. A sample O M manual is included. 3-ring binder included.
ERIC Educational Resources Information Center
Seeber, Susan; Lehmann, Rainer
2013-01-01
Germany has relied on its well-established tradition of preparing the workforce through the so-called dual system of practical in-firm training (apprenticeships) and theoretical foundations conveyed by vocational schools. Believing in the high quality of academic school programmes that prepare a small elite for university studies, the German…
Becoming a Principal in Indonesia: Possibility, Pitfalls and Potential
ERIC Educational Resources Information Center
Sumintono, Bambang; Sheyoputri, Elslee Y. A.; Jiang, Na; Misbach, Ifa H.; Jumintono
2015-01-01
The preparation and development of school leaders is now considered to be fundamental to school and system improvement. In the pursuit of educational change and reform, the leadership of the principal is deemed to be of critical importance. This qualitative study is part of a large scale research project that is exploring principal preparation and…
Wang, Yunwei; Tong, Xili; Guo, Xiaoning; Wang, Yingyong; Jin, Guoqiang; Guo, Xiangyun
2013-11-29
Highly-qualified graphene was prepared by the ultrasonic exfoliation of commercial expanded graphite (EG) under the promotion of (NH4)2CO3 decomposition. The yield of graphene from the first exfoliation is 7 wt%, and it can be increased to more than 65 wt% by repeated exfoliations. Atomic force microscopy, x-ray photoelectron spectroscopy and Raman analysis show that the as-prepared graphene only has a few defects or oxides, and more than 95% of the graphene flakes have a thickness of ~1 nm. The electrochemical performance of the as-prepared graphene is comparable to reduced graphene oxide in the determination of dopamine (DA) from the mixed solution of ascorbic acid, uric acid and DA. These results show that the decomposition of (NH4)2CO3 molecules in the EG layers under ultrasonication promotes the exfoliation of graphite and provides a low-priced route for large scale production of highly-quality graphene.
NASA Astrophysics Data System (ADS)
Wang, Yunwei; Tong, Xili; Guo, Xiaoning; Wang, Yingyong; Jin, Guoqiang; Guo, Xiangyun
2013-11-01
Highly-qualified graphene was prepared by the ultrasonic exfoliation of commercial expanded graphite (EG) under the promotion of (NH4)2CO3 decomposition. The yield of graphene from the first exfoliation is 7 wt%, and it can be increased to more than 65 wt% by repeated exfoliations. Atomic force microscopy, x-ray photoelectron spectroscopy and Raman analysis show that the as-prepared graphene only has a few defects or oxides, and more than 95% of the graphene flakes have a thickness of ˜1 nm. The electrochemical performance of the as-prepared graphene is comparable to reduced graphene oxide in the determination of dopamine (DA) from the mixed solution of ascorbic acid, uric acid and DA. These results show that the decomposition of (NH4)2CO3 molecules in the EG layers under ultrasonication promotes the exfoliation of graphite and provides a low-priced route for large scale production of highly-quality graphene.
A guide to large-scale RNA sample preparation.
Baronti, Lorenzo; Karlsson, Hampus; Marušič, Maja; Petzold, Katja
2018-05-01
RNA is becoming more important as an increasing number of functions, both regulatory and enzymatic, are being discovered on a daily basis. As the RNA boom has just begun, most techniques are still in development and changes occur frequently. To understand RNA functions, revealing the structure of RNA is of utmost importance, which requires sample preparation. We review the latest methods to produce and purify a variation of RNA molecules for different purposes with the main focus on structural biology and biophysics. We present a guide aimed at identifying the most suitable method for your RNA and your biological question and highlighting the advantages of different methods. Graphical abstract In this review we present different methods for large-scale production and purification of RNAs for structural and biophysical studies.
Li, Xiao-Lin; Ge, Jian-Ping; Li, Ya-Dong
2004-11-19
Large-scale MoS2 and WS2 inorganic fullerene-like (IF) nanostructures (onionlike nanoparticles, nanotubes) and elegant three-dimensional nanoflowers (NF) have been selectively prepared through an atmospheric pressure chemical vapor deposition (APCVD) process with the reaction of chlorides and sulfur. The morphologies were controlled by adjusting the deposition position, the deposition temperature, and the flux of the carrier gas. All of the nanostructures have been characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). A reaction mechanism is proposed based on the experimental results. The surface area of MoS2 IF nanoparticles and the field-emission effect of as-prepared WS2 nanoflowers is reported.
Development of piezoelectric composites for transducers
NASA Astrophysics Data System (ADS)
Safari, A.
1994-07-01
For the past decade and a half, many different types of piezoelectric ceramic-polymer composites have been developed intended for transducer applications. These diphasic composites are prepared from non-active polymer, such as epoxy, and piezoelectric ceramic, such as PZT, in the form of filler powders, elongated fibers, multilayer and more complex three-dimensional structures. For the last four years, most of the efforts have been given to producing large area and fine scale PZT fiber composites. In this paper, processing of piezoelectric ceramic-polymer composites with various connectivity patterns are reviewed. Development of fine scale piezoelectric composites by lost mold, injection molding and the relic method are described. Research activities of different groups for preparing large area piezocomposites for hydrophone and actuator applications are briefly reviewed. Initial development of electrostrictive ceramics and composites are also
Lessons from historical rangeland revegetation for today's restoration
Bruce A. Roundy
1999-01-01
Rangeland revegetation in the Western United States historically was applied at a large scale for soil conservation and forage production purposes. Principles of revegetation that have developed over years of research include matching site potential and plant materials adaption, use of appropriate seedbed preparation and sowing techniques, and development of large...
Seismic safety in conducting large-scale blasts
NASA Astrophysics Data System (ADS)
Mashukov, I. V.; Chaplygin, V. V.; Domanov, V. P.; Semin, A. A.; Klimkin, M. A.
2017-09-01
In mining enterprises to prepare hard rocks for excavation a drilling and blasting method is used. With the approach of mining operations to settlements the negative effect of large-scale blasts increases. To assess the level of seismic impact of large-scale blasts the scientific staff of Siberian State Industrial University carried out expertise for coal mines and iron ore enterprises. Determination of the magnitude of surface seismic vibrations caused by mass explosions was performed using seismic receivers, an analog-digital converter with recording on a laptop. The registration results of surface seismic vibrations during production of more than 280 large-scale blasts at 17 mining enterprises in 22 settlements are presented. The maximum velocity values of the Earth’s surface vibrations are determined. The safety evaluation of seismic effect was carried out according to the permissible value of vibration velocity. For cases with exceedance of permissible values recommendations were developed to reduce the level of seismic impact.
Large-scale production of lipoplexes with long shelf-life.
Clement, Jule; Kiefer, Karin; Kimpfler, Andrea; Garidel, Patrick; Peschka-Süss, Regine
2005-01-01
The instability of lipoplex formulations is a major obstacle to overcome before their commercial application in gene therapy. In this study, a continuous mixing technique for the large-scale preparation of lipoplexes followed by lyophilisation for increased stability and shelf-life has been developed. Lipoplexes were analysed for transfection efficiency and cytotoxicity in human aorta smooth muscle cells (HASMC) and a rat smooth muscle cell line (A-10 SMC). Homogeneity of lipid/DNA-products was investigated by photon correlation spectroscopy (PCS) and cryotransmission electron microscopy (cryo-TEM). Studies have been undertaken with DAC-30, a composition of 3beta-[N-(N,N'-dimethylaminoethane)-carbamoyl]-cholesterol (DAC-Chol) and dioleylphosphatidylethanolamine (DOPE) and a green fluorescent protein (GFP) expressing marker plasmid. A continuous mixing technique was compared to the small-scale preparation of lipoplexes by pipetting. Individual steps of the continuous mixing process were evaluated in order to optimise the manufacturing technique: lipid/plasmid ratio, composition of transfection medium, pre-treatment of the lipid, size of the mixing device, mixing procedure and the influence of the lyophilisation process. It could be shown that the method developed for production of lipoplexes on a large scale under sterile conditions led to lipoplexes with good transfection efficiencies combined with low cytotoxicity, improved characteristics and long shelf-life.
TARGET Publication Guidelines | Office of Cancer Genomics
Like other NCI large-scale genomics initiatives, TARGET is a community resource project and data are made available rapidly after validation for use by other researchers. To act in accord with the Fort Lauderdale principles and support the continued prompt public release of large-scale genomic data prior to publication, researchers who plan to prepare manuscripts containing descriptions of TARGET pediatric cancer data that would be of comparable scope to an initial TARGET disease-specific comprehensive, global analysis publication, and journal editors who receive such manuscripts, are
Primary-Graders Study Nutrition
ERIC Educational Resources Information Center
Niedermeyer, Fred C.; Moncrief, Michael H.
1975-01-01
Describes the content of an instructional unit on nutrition prepared by the Dairy Council of California for primary-level school children and the results of its large-scale tryout in 30 California schools. (SDH)
Platinum clusters with precise numbers of atoms for preparative-scale catalysis.
Imaoka, Takane; Akanuma, Yuki; Haruta, Naoki; Tsuchiya, Shogo; Ishihara, Kentaro; Okayasu, Takeshi; Chun, Wang-Jae; Takahashi, Masaki; Yamamoto, Kimihisa
2017-09-25
Subnanometer noble metal clusters have enormous potential, mainly for catalytic applications. Because a difference of only one atom may cause significant changes in their reactivity, a preparation method with atomic-level precision is essential. Although such a precision with enough scalability has been achieved by gas-phase synthesis, large-scale preparation is still at the frontier, hampering practical applications. We now show the atom-precise and fully scalable synthesis of platinum clusters on a milligram scale from tiara-like platinum complexes with various ring numbers (n = 5-13). Low-temperature calcination of the complexes on a carbon support under hydrogen stream affords monodispersed platinum clusters, whose atomicity is equivalent to that of the precursor complex. One of the clusters (Pt 10 ) exhibits high catalytic activity in the hydrogenation of styrene compared to that of the other clusters. This method opens an avenue for the application of these clusters to preparative-scale catalysis.The catalytic activity of a noble metal nanocluster is tied to its atomicity. Here, the authors report an atom-precise, fully scalable synthesis of platinum clusters from molecular ring precursors, and show that a variation of only one atom can dramatically change a cluster's reactivity.
Forced Alignment for Understudied Language Varieties: Testing Prosodylab-Aligner with Tongan Data
ERIC Educational Resources Information Center
Johnson, Lisa M.; Di Paolo, Marianna; Bell, Adrian
2018-01-01
Automated alignment of transcriptions to audio files expedites the process of preparing data for acoustic analysis. Unfortunately, the benefits of auto-alignment have generally been available only to researchers studying majority languages, for which large corpora exist and for which acoustic models have been created by large-scale research…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hong, Young Jun; Choi, Seung Ho; Sim, Chul Min
2012-12-15
Graphical abstract: Display Omitted Highlights: ► Spherical shape Li{sub 2}MnO{sub 3}·LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} composite cathode powders are prepared by large-scale spray pyrolysis with droplet classifier. ► Boric acid improves the morphological and electrochemical properties of the composite cathode powders. ► The discharge capacity of the composite cathode powders decreases from 217 to 196 mAh g{sup −1} by the 30th cycle. -- Abstract: Spherically shaped 0.3Li{sub 2}MnO{sub 3}·0.7LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} composite cathode powders with filled morphology and narrow size distribution are prepared by large-scale spray pyrolysis. A droplet classification reduces the standard deviation of the size distribution of themore » composite cathode powders. Addition of boric acid improves the morphological properties of the product powders by forming a lithium borate glass material with low melting temperature. The optimum amount of boric acid dissolved in the spray solution is 0.8 wt% of the composite powders. The powders prepared from the spray solution with 0.8 wt% boric acid have a mixed layered crystal structure comprising Li{sub 2}MnO{sub 3} and LiNi{sub 0.5}Mn{sub 0.5}O{sub 2} phases, thus forming a composite compound. The initial charge and discharge capacities of the composite cathode powders prepared from the 0.8 wt% boric acid spray solution are 297 and 217 mAh g{sup −1}, respectively. The discharge capacity of the powders decreases from 217 to 196 mAh g{sup −1} by the 30th cycle, in which the capacity retention is 90%.« less
Achieving Agility and Stability in Large-Scale Software Development
2013-01-16
temporary team is assigned to prepare layers and frameworks for future feature teams. Presentation Layer Domain Layer Data Access Layer...http://www.sei.cmu.edu/training/ elearning ~ Software Engineering Institute CarnegieMellon
ERIC Educational Resources Information Center
Tesfamariam, Gebrekidan Mebrahtu; Lykknes, Annette; Kvittingen, Lise
2017-01-01
In theory, practical work is an established part of university-level chemistry courses. However, mainly due to budget constraints, large class size, time constraints and inadequate teacher preparations, practical activities are frequently left out from chemistry classroom instruction in most developing countries. Small-scale chemistry (SSC)…
Achieving Agility and Stability in Large-Scale Software Development
2013-01-16
temporary team is assigned to prepare layers and frameworks for future feature teams. Presentation Layer Domain Layer Data Access Layer Framework...http://www.sei.cmu.edu/training/ elearning ~ Software Engineering Institute CarnegieMellon
Kim, Hyoung Jun; Kim, Tae Oh; Shin, Bong Chul; Woo, Jae Gon; Seo, Eun Hee; Joo, Hee Rin; Heo, Nae-Yun; Park, Jongha; Park, Seung Ha; Yang, Sung Yeon; Moon, Young Soo; Shin, Jin-Yong; Lee, Nae Young
2012-01-01
Currently, a split-dose of polyethylene glycol (PEG) is the mainstay of bowel preparation due to its tolerability, bowel-cleansing action, and safety. However, bowel preparation with PEG is suboptimal because residual fluid reduces the polyp detection rate and requires a more thorough colon inspection. The aim of our study was to demonstrate the efficacy of a sufficient dose of prokinetics on bowel cleansing together with split-dose PEG. A prospective endoscopist-blinded study was conducted. Patients were randomly allocated to two groups: prokinetic with split-dose PEG or split-dose PEG alone. A prokinetic [100 mg itopride (Itomed)], was administered twice simultaneously with each split-dose of PEG. Bowel-cleansing efficacy was measured by endoscopists using the Ottawa scale and the segmental fluidity scale score. Each participant completed a bowel preparation survey. Mean scores from the Ottawa scale, segmental fluid scale, and rate of poor preparation were compared between both groups. Patients in the prokinetics with split-dose PEG group showed significantly lower total Ottawa and segmental fluid scores compared with patients in the split-dose of PEG alone group. A sufficient dose of prokinetics with a split-dose of PEG showed efficacy in bowel cleansing for morning colonoscopy, largely due to the reduction in colonic fluid. Copyright © 2012 S. Karger AG, Basel.
Katsura, Kazushige; Matsuda, Takayoshi; Tomabechi, Yuri; Yonemochi, Mayumi; Hanada, Kazuharu; Ohsawa, Noboru; Sakamoto, Kensaku; Takemoto, Chie; Shirouzu, Mikako
2017-11-01
Cell-free protein synthesis is a useful method for preparing proteins for functional or structural analyses. However, batch-to-batch variability with regard to protein synthesis activity remains a problem for large-scale production of cell extract in the laboratory. To address this issue, we have developed a novel procedure for large-scale preparation of bacterial cell extract with high protein synthesis activity. The developed procedure comprises cell cultivation using a fermentor, harvesting and washing of cells by tangential flow filtration, cell disruption with high-pressure homogenizer and continuous diafiltration. By optimizing and combining these methods, ∼100 ml of the cell extract was prepared from 150 g of Escherichia coli cells. The protein synthesis activities, defined as the yield of protein per unit of absorbance at 260 nm of the cell extract, were shown to be reproducible, and the average activity of several batches was twice that obtained using a previously reported method. In addition, combinatorial use of the high-pressure homogenizer and diafiltration increased the scalability, indicating that the cell concentration at disruption varies from 0.04 to 1 g/ml. Furthermore, addition of Gam protein and examinations of the N-terminal sequence rendered the extract prepared here useful for rapid screening with linear DNA templates. © The Authors 2017. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.
NASA Astrophysics Data System (ADS)
He, Xiangming; Li, Jianjun; Cheng, Hongwei; Jiang, Changyin; Wan, Chunrong
A novel synthesis of controlled crystallization and granulation was attempted to prepare nano-scale β-Ni(OH) 2 cathode materials for high power Ni-MH batteries. Nano-scale β-Ni(OH) 2 and Co(OH) 2 with a diameter of 20 nm were prepared by controlled crystallization, mixed by ball milling, and granulated to form about 5 μm spherical grains by spray drying granulation. Both the addition of nano-scale Co(OH) 2 and granulation significantly enhanced electrochemical performance of nano-scale Ni(OH) 2. The XRD and TEM analysis shown that there were a large amount of defects among the crystal lattice of as-prepared nano-scale Ni(OH) 2, and the DTA-TG analysis shown that it had both lower decomposition temperature and higher decomposition reaction rate, indicating less thermal stability, as compared with conventional micro-scale Ni(OH) 2, and indicating that it had higher electrochemical performance. The granulated grains of nano-scale Ni(OH) 2 mixed with nano-scale Co(OH) 2 at Co/Ni = 1/20 presented the highest specific capacity reaching its theoretical value of 289 mAh g -1 at 1 C, and also exhibited much improved electrochemical performance at high discharge capacity rate up to 10 C. The granulated grains of nano-scale β-Ni(OH) 2 mixed with nano-scale Co(OH) 2 is a promising cathode active material for high power Ni-MH batteries.
Large Scale Synthesis and Light Emitting Fibers of Tailor-Made Graphene Quantum Dots
Park, Hun; Hyun Noh, Sung; Hye Lee, Ji; Jun Lee, Won; Yun Jaung, Jae; Geol Lee, Seung; Hee Han, Tae
2015-01-01
Graphene oxide (GO), which is an oxidized form of graphene, has a mixed structure consisting of graphitic crystallites of sp2 hybridized carbon and amorphous regions. In this work, we present a straightforward route for preparing graphene-based quantum dots (GQDs) by extraction of the crystallites from the amorphous matrix of the GO sheets. GQDs with controlled functionality are readily prepared by varying the reaction temperature, which results in precise tunability of their optical properties. Here, it was concluded that the tunable optical properties of GQDs are a result of the different fraction of chemical functionalities present. The synthesis approach presented in this paper provides an efficient strategy for achieving large-scale production and long-time optical stability of the GQDs, and the hybrid assembly of GQD and polymer has potential applications as photoluminescent fibers or films. PMID:26383257
NASA Astrophysics Data System (ADS)
Gad-El-Hak, Mohamed
"Extreme" events - including climatic events, such as hurricanes, tornadoes, and drought - can cause massive disruption to society, including large death tolls and property damage in the billions of dollars. Events in recent years have shown the importance of being prepared and that countries need to work together to help alleviate the resulting pain and suffering. This volume presents a review of the broad research field of large-scale disasters. It establishes a common framework for predicting, controlling and managing both manmade and natural disasters. There is a particular focus on events caused by weather and climate change. Other topics include air pollution, tsunamis, disaster modeling, the use of remote sensing and the logistics of disaster management. It will appeal to scientists, engineers, first responders and health-care professionals, in addition to graduate students and researchers who have an interest in the prediction, prevention or mitigation of large-scale disasters.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fishkind, H.H.
1982-04-01
The feasibility of large-scale plantation establishment by various methods was examined, and the following conclusions were reached: seedling plantations are limited in potential yield due to genetic variation among the planting stock and often inadequate supplies of appropriate seed; vegetative propagation by rooted cuttings can provide good genetic uniformity of select hybrid planting stock; however, large-scale production requires establishment and maintenance of extensive cutting orchards. The collection of shoots and preparation of cuttings, although successfully implemented in the Congo and Brazil, would not be economically feasible in Florida for large-scale plantations; tissue culture propagation of select hybrid eucalypts offers themore » only opportunity to produce the very large number of trees required to establish the energy plantation. The cost of tissue culture propagation, although higher than seedling production, is more than off-set by the increased productivity of vegetative plantations established from select hybrid Eucalyptus.« less
Application of ARC/INFO to regional scale hydrogeologic modeling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wurstner, S.K.; McWethy, G.; Devary, J.L.
1993-05-01
Geographic Information Systems (GIS) can be a useful tool in data preparation for groundwater flow modeling, especially when studying large regional systems. ARC/INFO is being used in conjunction with GRASS to support data preparation for input to the CFEST (Coupled Fluid, Energy, and Solute Transport) groundwater modeling code. Simulations will be performed with CFEST to model three-dimensional, regional, groundwater flow in the West Siberian Basin.
Walther, Cornelia; Kellner, Martin; Berkemeyer, Matthias; Brocard, Cécile; Dürauer, Astrid
2017-10-21
Escherichia coli stores large amounts of highly pure product within inclusion bodies (IBs). To take advantage of this beneficial feature, after cell disintegration, the first step to optimal product recovery is efficient IB preparation. This step is also important in evaluating upstream optimization and process development, due to the potential impact of bioprocessing conditions on product quality and on the nanoscale properties of IBs. Proper IB preparation is often neglected, due to laboratory-scale methods requiring large amounts of materials and labor. Miniaturization and parallelization can accelerate analyses of individual processing steps and provide a deeper understanding of up- and downstream processing interdependencies. Consequently, reproducible, predictive microscale methods are in demand. In the present study, we complemented a recently established high-throughput cell disruption method with a microscale method for preparing purified IBs. This preparation provided results comparable to laboratory-scale IB processing, regarding impurity depletion, and product loss. Furthermore, with this method, we performed a "design of experiments" study to demonstrate the influence of fermentation conditions on the performance of subsequent downstream steps and product quality. We showed that this approach provided a 300-fold reduction in material consumption for each fermentation condition and a 24-fold reduction in processing time for 24 samples.
Taheri, Mohammadreza; Moazeni-Pourasil, Roudabeh Sadat; Sheikh-Olia-Lavasani, Majid; Karami, Ahmad; Ghassempour, Alireza
2016-03-01
Chromatographic method development for preparative targets is a time-consuming and subjective process. This can be particularly problematic because of the use of valuable samples for isolation and the large consumption of solvents in preparative scale. These processes could be improved by using statistical computations to save time, solvent and experimental efforts. Thus, contributed by ESI-MS, after applying DryLab software to gain an overview of the most effective parameters in separation of synthesized celecoxib and its co-eluted compounds, design of experiment software that relies on multivariate modeling as a chemometric approach was used to predict the optimized touching-band overloading conditions by objective functions according to the relationship between selectivity and stationary phase properties. The loadability of the method was investigated on the analytical and semi-preparative scales, and the performance of this chemometric approach was approved by peak shapes beside recovery and purity of products. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Zhang, Panpan; Huang, Ying; Lu, Xin; Zhang, Siyu; Li, Jingfeng; Wei, Gang; Su, Zhiqiang
2014-07-29
We demonstrated a facile one-step synthesis strategy for the preparation of a large-scale reduced graphene oxide multilayered film doped with gold nanoparticles (RGO/AuNP film) and applied this film as functional nanomaterials for electrochemistry and Raman detection applications. The related applications of the fabricated RGO/AuNP film in electrochemical nonenzymatic H2O2 biosensor, electrochemical oxygen reduction reaction (ORR), and surface-enhanced Raman scattering (SERS) detection were investigated. Electrochemical data indicate that the H2O2 biosensor fabricated by RGO/AuNP film shows a wide linear range, low limitation of detection, high selectivity, and long-term stability. In addition, it was proved that the created RGO/AuNP film also exhibits excellent ORR electrochemical catalysis performance. The created RGO/AuNP film, when serving as SERS biodetection platform, presents outstanding performances in detecting 4-aminothiophenol with an enhancement factor of approximately 5.6 × 10(5) as well as 2-thiouracil sensing with a low concentration to 1 μM. It is expected that this facile strategy for fabricating large-scale graphene film doped with metallic nanoparticles will spark inspirations in preparing functional nanomaterials and further extend their applications in drug delivery, wastewater purification, and bioenergy.
Lu, Xunyu; Zhao, Chuan
2015-01-01
Large-scale industrial application of electrolytic splitting of water has called for the development of oxygen evolution electrodes that are inexpensive, robust and can deliver large current density (>500 mA cm−2) at low applied potentials. Here we show that an efficient oxygen electrode can be developed by electrodepositing amorphous mesoporous nickel–iron composite nanosheets directly onto macroporous nickel foam substrates. The as-prepared oxygen electrode exhibits high catalytic activity towards water oxidation in alkaline solutions, which only requires an overpotential of 200 mV to initiate the reaction, and is capable of delivering current densities of 500 and 1,000 mA cm−2 at overpotentials of 240 and 270 mV, respectively. The electrode also shows prolonged stability against bulk water electrolysis at large current. Collectively, the as-prepared three-dimensional structured electrode is the most efficient oxygen evolution electrode in alkaline electrolytes reported to the best of our knowledge, and can potentially be applied for industrial scale water electrolysis. PMID:25776015
Hennig, Bianca P.; Velten, Lars; Racke, Ines; Tu, Chelsea Szu; Thoms, Matthias; Rybin, Vladimir; Besir, Hüseyin; Remans, Kim; Steinmetz, Lars M.
2017-01-01
Efficient preparation of high-quality sequencing libraries that well represent the biological sample is a key step for using next-generation sequencing in research. Tn5 enables fast, robust, and highly efficient processing of limited input material while scaling to the parallel processing of hundreds of samples. Here, we present a robust Tn5 transposase purification strategy based on an N-terminal His6-Sumo3 tag. We demonstrate that libraries prepared with our in-house Tn5 are of the same quality as those processed with a commercially available kit (Nextera XT), while they dramatically reduce the cost of large-scale experiments. We introduce improved purification strategies for two versions of the Tn5 enzyme. The first version carries the previously reported point mutations E54K and L372P, and stably produces libraries of constant fragment size distribution, even if the Tn5-to-input molecule ratio varies. The second Tn5 construct carries an additional point mutation (R27S) in the DNA-binding domain. This construct allows for adjustment of the fragment size distribution based on enzyme concentration during tagmentation, a feature that opens new opportunities for use of Tn5 in customized experimental designs. We demonstrate the versatility of our Tn5 enzymes in different experimental settings, including a novel single-cell polyadenylation site mapping protocol as well as ultralow input DNA sequencing. PMID:29118030
NASA Astrophysics Data System (ADS)
Sasaki, Yuki; Kitaura, Ryo; Yuk, Jong Min; Zettl, Alex; Shinohara, Hisanori
2016-04-01
By utilizing graphene-sandwiched structures recently developed in this laboratory, we are able to visualize small droplets of liquids in nanometer scale. We have found that small water droplets as small as several tens of nanometers sandwiched by two single-layer graphene are frequently observed by TEM. Due to the electron beam irradiation during the TEM observation, these sandwiched droplets are frequently moving from one place to another and are subjected to create small bubbles inside. The synthesis of a large area single-domain graphene of high-quality is essential to prepare the graphene sandwiched cell which safely encapsulates the droplets in nanometer size.
NASA Technical Reports Server (NTRS)
Gilligan, J. E.; Harada, Y.
1974-01-01
The development of a large scale manufacturing method for the production of a stable zinc orthotitanate pigment is discussed. Major emphasis was placed on the evaluation of ultraviolet radiation stability tests of pigments derived from coprecipitated and individually precipitated oxalates. Emphasis was also placed on an investigation of the conditions (time and temperature) leading to high reflectance and high optical stability. Paints were formulated in OI-650 and in OI-650G vehicles from pigments which were prepared at various temperatures. Analyses of ultraviolet irradiation test data were conducted regarding optimum pigment preparation parameters and treatment conditions.
Characteristics of transitional and turbulent jet diffusion flames in microgravity
NASA Technical Reports Server (NTRS)
Bahadori, Yousef M.; Small, James F., Jr.; Hegde, Uday G.; Zhou, Liming; Stocker, Dennis P.
1995-01-01
This paper presents the ground-based results obtained to date in preparation of a proposed space experiment to study the role of large-scale structures in microgravity transitional and turbulent gas-jet diffusion flames by investigating the dynamics of vortex/flame interactions and their influence on flame characteristics. The overall objective is to gain an understanding of the fundamental characteristics of transitional and turbulent gas-jet diffusion flames. Understanding of the role of large-scale structures on the characteristics of microgravity transitional and turbulent flames will ultimately lead to improved understanding of normal-gravity turbulent combustion.
Mass Spectrometry as a Preparative Tool for the Surface Science of Large Molecules
NASA Astrophysics Data System (ADS)
Rauschenbach, Stephan; Ternes, Markus; Harnau, Ludger; Kern, Klaus
2016-06-01
Measuring and understanding the complexity that arises when nanostructures interact with their environment are one of the major current challenges of nanoscale science and technology. High-resolution microscopy methods such as scanning probe microscopy have the capacity to investigate nanoscale systems with ultimate precision, for which, however, atomic scale precise preparation methods of surface science are a necessity. Preparative mass spectrometry (pMS), defined as the controlled deposition of m/z filtered ion beams, with soft ionization sources links the world of large, biological molecules and surface science, enabling atomic scale chemical control of molecular deposition in ultrahigh vacuum (UHV). Here we explore the application of high-resolution scanning probe microscopy and spectroscopy to the characterization of structure and properties of large molecules. We introduce the fundamental principles of the combined experiments electrospray ion beam deposition and scanning tunneling microscopy. Examples for the deposition and investigation of single particles, for layer and film growth, and for the investigation of electronic properties of individual nonvolatile molecules show that state-of-the-art pMS technology provides a platform analog to thermal evaporation in conventional molecular beam epitaxy. Additionally, it offers additional, unique features due to the use of charged polyatomic particles. This new field is an enormous sandbox for novel molecular materials research and demands the development of advanced molecular ion beam technology.
2011-01-01
Background Studies of nuclear function in many organisms, especially those with tough cell walls, are limited by lack of availability of simple, economical methods for large-scale preparation of clean, undamaged nuclei. Findings Here we present a useful method for nuclear isolation from the important model organism, the fission yeast, Schizosaccharomyces pombe. To preserve in vivo molecular configurations, we flash-froze the yeast cells in liquid nitrogen. Then we broke their tough cell walls, without damaging their nuclei, by grinding in a precision-controlled motorized mortar-and-pestle apparatus. The cryo-ground cells were resuspended and thawed in a buffer designed to preserve nuclear morphology, and the nuclei were enriched by differential centrifugation. The washed nuclei were free from contaminating nucleases and have proven well-suited as starting material for genome-wide chromatin analysis and for preparation of fragile DNA replication intermediates. Conclusions We have developed a simple, reproducible, economical procedure for large-scale preparation of endogenous-nuclease-free, morphologically intact nuclei from fission yeast. With appropriate modifications, this procedure may well prove useful for isolation of nuclei from other organisms with, or without, tough cell walls. PMID:22088094
Givens, Robert M; Mesner, Larry D; Hamlin, Joyce L; Buck, Michael J; Huberman, Joel A
2011-11-16
Studies of nuclear function in many organisms, especially those with tough cell walls, are limited by lack of availability of simple, economical methods for large-scale preparation of clean, undamaged nuclei. Here we present a useful method for nuclear isolation from the important model organism, the fission yeast, Schizosaccharomyces pombe. To preserve in vivo molecular configurations, we flash-froze the yeast cells in liquid nitrogen. Then we broke their tough cell walls, without damaging their nuclei, by grinding in a precision-controlled motorized mortar-and-pestle apparatus. The cryo-ground cells were resuspended and thawed in a buffer designed to preserve nuclear morphology, and the nuclei were enriched by differential centrifugation. The washed nuclei were free from contaminating nucleases and have proven well-suited as starting material for genome-wide chromatin analysis and for preparation of fragile DNA replication intermediates. We have developed a simple, reproducible, economical procedure for large-scale preparation of endogenous-nuclease-free, morphologically intact nuclei from fission yeast. With appropriate modifications, this procedure may well prove useful for isolation of nuclei from other organisms with, or without, tough cell walls.
Unique intermetallic compounds prepared by shock wave synthesis
NASA Technical Reports Server (NTRS)
Otto, G.; Reece, O. Y.; Roy, U.
1971-01-01
Technique compresses fine ground metallic powder mixture beyond crystal fusion point. Absence of vapor pressure voids and elimination of incongruous effects permit application of technique to large scale fabrication of intermetallic compounds with specific characteristics, e.g., semiconduction, superconduction, or magnetic properties.
Scaling up digital circuit computation with DNA strand displacement cascades.
Qian, Lulu; Winfree, Erik
2011-06-03
To construct sophisticated biochemical circuits from scratch, one needs to understand how simple the building blocks can be and how robustly such circuits can scale up. Using a simple DNA reaction mechanism based on a reversible strand displacement process, we experimentally demonstrated several digital logic circuits, culminating in a four-bit square-root circuit that comprises 130 DNA strands. These multilayer circuits include thresholding and catalysis within every logical operation to perform digital signal restoration, which enables fast and reliable function in large circuits with roughly constant switching time and linear signal propagation delays. The design naturally incorporates other crucial elements for large-scale circuitry, such as general debugging tools, parallel circuit preparation, and an abstraction hierarchy supported by an automated circuit compiler.
One-pot synthesis of hypervalent iodine reagents for electrophilic trifluoromethylation.
Matoušek, Václav; Pietrasiak, Ewa; Schwenk, Rino; Togni, Antonio
2013-07-05
Simplified syntheses suited for large scale preparations of the two hypervalent iodine reagents 1 and 2 for electrophilic trifluoromethylation are reported. In both cases, the stoichiometric oxidants sodium metaperiodate and tert-butyl hypochlorite have been replaced by trichloroisocyanuric acid. Reagent 1 is accessible in a one-pot procedure from 2-iodobenzoic acid in 72% yield. Reagent 2 was prepared via fluoroiodane 11 in a considerably shorter reaction time and with no need of an accurate temperature control.
[A bomb attack in the Netherlands; how would we provide hospital care?
Haverkort, J J M; de Jong, M B; van Spengler, L L; Leenen, L P H
2017-01-01
- There is an ever-present threat of large-scale incidents and disasters, such as terrorism and natural disasters.- Preparation and planning are the key to successful response to major incidents and disasters, which is why education, training sessions and exercises take place in the Netherlands.- Analysis of recent large-scale incidents in Europe and the USA emphasises the importance of adequate distribution of the wounded to centres where the correct care can be provided.- A major step has been taken in the Netherlands to provide for such an eventuality with the introduction of distribution plans for the wounded, and other initiatives such as a regional hospital disaster plan.- If a large-scale incident should take place the Netherlands also has a Major Incident Hospital at its disposal; this is a unique facility that can guarantee availability of 200 spare beds to the Netherlands healthcare system within 30 minutes.
Chu, Yen Li; Farmer, Anna; Fung, Christina; Kuhle, Stefan; Storey, Kate E; Veugelers, Paul J
2013-01-01
To examine the association between frequency of assisting with home meal preparation and fruit and vegetable preference and self-efficacy for making healthier food choices among grade 5 children in Alberta, Canada. A cross-sectional survey design was used. Children were asked how often they helped prepare food at home and rated their preference for twelve fruits and vegetables on a 3-point Likert-type scale. Self-efficacy was measured with six items on a 4-point Likert-type scale asking children their level of confidence in selecting and eating healthy foods at home and at school. Schools (n =151) located in Alberta, Canada. Grade 5 students (n = 3398). A large majority (83-93 %) of the study children reported helping in home meal preparation at least once monthly. Higher frequency of helping prepare and cook food at home was associated with higher fruit and vegetable preference and with higher self-efficacy for selecting and eating healthy foods. Encouraging children to be more involved in home meal preparation could be an effective health promotion strategy. These findings suggest that the incorporation of activities teaching children how to prepare simple and healthy meals in health promotion programmes could potentially lead to improvement in dietary habits.
ERIC Educational Resources Information Center
Wolf, Walter A., Ed.
1978-01-01
Reported here are brief descriptions of a common grading and scaling formula for large multi-section courses, an ion exchange amino acid separation and thin layer chromatography identification experiment, a conservation of energy demonstration, a catalyst for synthesizing esters from fatty aids, and an inexpensive method for preparing platinum…
A scalable and operationally simple radical trifluoromethylation
Beatty, Joel W.; Douglas, James J.; Cole, Kevin P.; Stephenson, Corey R. J.
2015-01-01
The large number of reagents that have been developed for the synthesis of trifluoromethylated compounds is a testament to the importance of the CF3 group as well as the associated synthetic challenge. Current state-of-the-art reagents for appending the CF3 functionality directly are highly effective; however, their use on preparative scale has minimal precedent because they require multistep synthesis for their preparation, and/or are prohibitively expensive for large-scale application. For a scalable trifluoromethylation methodology, trifluoroacetic acid and its anhydride represent an attractive solution in terms of cost and availability; however, because of the exceedingly high oxidation potential of trifluoroacetate, previous endeavours to use this material as a CF3 source have required the use of highly forcing conditions. Here we report a strategy for the use of trifluoroacetic anhydride for a scalable and operationally simple trifluoromethylation reaction using pyridine N-oxide and photoredox catalysis to affect a facile decarboxylation to the CF3 radical. PMID:26258541
Evaluation of fuel preparation systems for lean premixing-prevaporizing combustors
NASA Technical Reports Server (NTRS)
Dodds, W. J.; Ekstedt, E. E.
1985-01-01
A series of experiments was carried out in order to produce design data for a premixing prevaporizing fuel-air mixture preparation system for aircraft gas turbine engine combustors. The fuel-air mixture uniformity of four different system design concepts was evaluated over a range of conditions representing the cruise operation of a modern commercial turbofan engine. Operating conditions including pressure, temperature, fuel-to-air ratio, and velocity, exhibited no clear effect on mixture uniformity of systems using pressure-atomizing fuel nozzles and large-scale mixing devices. However, the performance of systems using atomizing fuel nozzles and large-scale mixing devices was found to be sensitive to operating conditions. Variations in system design variables were also evaluated and correlated. Mixing uniformity was found to improve with system length, pressure drop, and the number of fuel injection points per unit area. A premixing system capable of providing mixing uniformity to within 15 percent over a typical range of cruise operating conditions is demonstrated.
NASA Astrophysics Data System (ADS)
Hua, Wei-Bo; Guo, Xiao-Dong; Zheng, Zhuo; Wang, Yan-Jie; Zhong, Ben-He; Fang, Baizeng; Wang, Jia-Zhao; Chou, Shu-Lei; Liu, Heng
2015-02-01
Developing advanced electrode materials that deliver high energy at ultra-fast charge and discharge rates are very crucial to meet an increasing large-scale market demand for high power lithium ion batteries (LIBs). A three-dimensional (3D) nanoflower structure is successfully developed in the large-scale synthesis of LiNi1/3Co1/3Mn1/3O2 material for the first time. The fast co-precipitation is the key technique to prepare the nanoflower structure in our method. After heat treatment, the obtained LiNi1/3Co1/3Mn1/3O2 nanoflowers (NL333) pronouncedly present a pristine flower-like nano-architecture and provide fast pathways for the transport of Li-ions and electrons. As a cathode material in a LIB, the prepared NL333 electrode demonstrates an outstanding high-rate capability. Particularly, in a narrow voltage range of 2.7-4.3 V, the discharge capacity at an ultra-fast charge-discharge rate (20C) is up to 126 mAh g-1, which reaches 78% of that at 0.2C, and is much higher than that (i.e., 44.17%) of the traditional bulk LiNi1/3Co1/3Mn1/3O2.
High quality uniform YBCO film growth by the metalorganic deposition using trifluoroacetates
NASA Astrophysics Data System (ADS)
Wang, S. S.; Zhang, Z. L.; Wang, L.; Gao, L. K.; Liu, J.
2017-03-01
A need exists for the large-area superconducting YBa2Cu3O7-x (YBCO) films with high critical current density for microwave communication and/or electric power applications. Trifluoroacetic metalorganic (TFA-MOD) method is a promising low cost technique for large-scale production of YBCO films, because it does not need high vacuum device and is easily applicable to substrates of various shape and size. In this paper, double-sided YBCO films with maximum 2 in diameter were prepared on LaAlO3 substrates by TFA-MOD method. Inductive critical current densitiy Jc, microwave surface resistance Rs, as well as the microstructure were characterized. A newly homemade furnace system was used to epitaxially grown YBCO films, which can improve the uniformity of YBCO film significantly by gas supply and temperature distribution proper design. Results showed that the large area YBCO films were very uniform in microstructure and thickness distribution, an average inductive Jc in excess of 6 MA/cm2 with uniform distribution, and low Rs (10 GHz) below 0.3 mΩ at 77 K were obtained. Andthe film filter may be prepared to work at temperatures lower than 74 K. These results are very close to the highest value of YBCO films made by conventional vacuum method, so we show a very promising route for large-scale production of high quality large-area YBCO superconducting films at a lower cost.
Theory of wavelet-based coarse-graining hierarchies for molecular dynamics.
Rinderspacher, Berend Christopher; Bardhan, Jaydeep P; Ismail, Ahmed E
2017-07-01
We present a multiresolution approach to compressing the degrees of freedom and potentials associated with molecular dynamics, such as the bond potentials. The approach suggests a systematic way to accelerate large-scale molecular simulations with more than two levels of coarse graining, particularly applications of polymeric materials. In particular, we derive explicit models for (arbitrarily large) linear (homo)polymers and iterative methods to compute large-scale wavelet decompositions from fragment solutions. This approach does not require explicit preparation of atomistic-to-coarse-grained mappings, but instead uses the theory of diffusion wavelets for graph Laplacians to develop system-specific mappings. Our methodology leads to a hierarchy of system-specific coarse-grained degrees of freedom that provides a conceptually clear and mathematically rigorous framework for modeling chemical systems at relevant model scales. The approach is capable of automatically generating as many coarse-grained model scales as necessary, that is, to go beyond the two scales in conventional coarse-grained strategies; furthermore, the wavelet-based coarse-grained models explicitly link time and length scales. Furthermore, a straightforward method for the reintroduction of omitted degrees of freedom is presented, which plays a major role in maintaining model fidelity in long-time simulations and in capturing emergent behaviors.
Atomic-scale epitaxial aluminum film on GaAs substrate
NASA Astrophysics Data System (ADS)
Fan, Yen-Ting; Lo, Ming-Cheng; Wu, Chu-Chun; Chen, Peng-Yu; Wu, Jenq-Shinn; Liang, Chi-Te; Lin, Sheng-Di
2017-07-01
Atomic-scale metal films exhibit intriguing size-dependent film stability, electrical conductivity, superconductivity, and chemical reactivity. With advancing methods for preparing ultra-thin and atomically smooth metal films, clear evidences of the quantum size effect have been experimentally collected in the past two decades. However, with the problems of small-area fabrication, film oxidation in air, and highly-sensitive interfaces between the metal, substrate, and capping layer, the uses of the quantized metallic films for further ex-situ investigations and applications have been seriously limited. To this end, we develop a large-area fabrication method for continuous atomic-scale aluminum film. The self-limited oxidation of aluminum protects and quantizes the metallic film and enables ex-situ characterizations and device processing in air. Structure analysis and electrical measurements on the prepared films imply the quantum size effect in the atomic-scale aluminum film. Our work opens the way for further physics studies and device applications using the quantized electronic states in metals.
Terkola, R; Czejka, M; Bérubé, J
2017-08-01
Medication errors are a significant cause of morbidity and mortality especially with antineoplastic drugs, owing to their narrow therapeutic index. Gravimetric workflow software systems have the potential to reduce volumetric errors during intravenous antineoplastic drug preparation which may occur when verification is reliant on visual inspection. Our aim was to detect medication errors with possible critical therapeutic impact as determined by the rate of prevented medication errors in chemotherapy compounding after implementation of gravimetric measurement. A large-scale, retrospective analysis of data was carried out, related to medication errors identified during preparation of antineoplastic drugs in 10 pharmacy services ("centres") in five European countries following the introduction of an intravenous workflow software gravimetric system. Errors were defined as errors in dose volumes outside tolerance levels, identified during weighing stages of preparation of chemotherapy solutions which would not otherwise have been detected by conventional visual inspection. The gravimetric system detected that 7.89% of the 759 060 doses of antineoplastic drugs prepared at participating centres between July 2011 and October 2015 had error levels outside the accepted tolerance range set by individual centres, and prevented these doses from reaching patients. The proportion of antineoplastic preparations with deviations >10% ranged from 0.49% to 5.04% across sites, with a mean of 2.25%. The proportion of preparations with deviations >20% ranged from 0.21% to 1.27% across sites, with a mean of 0.71%. There was considerable variation in error levels for different antineoplastic agents. Introduction of a gravimetric preparation system for antineoplastic agents detected and prevented dosing errors which would not have been recognized with traditional methods and could have resulted in toxicity or suboptimal therapeutic outcomes for patients undergoing anticancer treatment. © 2017 The Authors. Journal of Clinical Pharmacy and Therapeutics Published by John Wiley & Sons Ltd.
1972-02-21
is a two-sided strategic nuclear exchange war gaming system. It is designed co assist the military planner in examining various facets of strategic...substantial, the data base preparation process is designed to provide an efficient means of assembling, maintaining, and organizing an input data base to... designed to assist in the study of &’trategic conflicts involving a large-scale Pexchange of nuclear weapons. The system is structured into five
Strongly luminescent monolayered MoS2 prepared by effective ultrasound exfoliation.
Štengl, Václav; Henych, Jiří
2013-04-21
Intense ultrasound in a pressurized batch reactor was used for preparation of monolayered MoS2 nanosheets from natural mineral molybdenite. Exfoliation of bulk MoS2 using ultrasound is an attractive route to large-scale preparation of monolayered crystals. To evaluate the quality of delamination, methods like X-ray diffraction, Raman spectroscopy and microscopic techniques (TEM and AFM) were employed. From single- or few-layered products obtained from intense sonication, MoS2 quantum dots (MoSQDs) were prepared by a one-pot reaction by refluxing exfoliated nanosheets of MoS2 in ethylene glycol under atmospheric pressure. The synthesised MoSQDs were characterised by photoluminescence spectroscopy and laser-scattering particle size analysis. Our easy preparation leads to very strongly green luminescing quantum dots.
Starch-lipid inclusion complexes for aerogel formation
USDA-ARS?s Scientific Manuscript database
Recently we reported that aqueous slurries of starch can be excess steam jet-cooked and blended with aqueous solutions of fatty acid salts to produce inclusion complexes between amylose and the fatty acid salt. These complexes can be simply prepared on large scale using commercially available steam ...
Kuipers, Jeroen; Kalicharan, Ruby D; Wolters, Anouk H G; van Ham, Tjakko J; Giepmans, Ben N G
2016-05-25
Large-scale 2D electron microscopy (EM), or nanotomy, is the tissue-wide application of nanoscale resolution electron microscopy. Others and we previously applied large scale EM to human skin pancreatic islets, tissue culture and whole zebrafish larvae(1-7). Here we describe a universally applicable method for tissue-scale scanning EM for unbiased detection of sub-cellular and molecular features. Nanotomy was applied to investigate the healthy and a neurodegenerative zebrafish brain. Our method is based on standardized EM sample preparation protocols: Fixation with glutaraldehyde and osmium, followed by epoxy-resin embedding, ultrathin sectioning and mounting of ultrathin-sections on one-hole grids, followed by post staining with uranyl and lead. Large-scale 2D EM mosaic images are acquired using a scanning EM connected to an external large area scan generator using scanning transmission EM (STEM). Large scale EM images are typically ~ 5 - 50 G pixels in size, and best viewed using zoomable HTML files, which can be opened in any web browser, similar to online geographical HTML maps. This method can be applied to (human) tissue, cross sections of whole animals as well as tissue culture(1-5). Here, zebrafish brains were analyzed in a non-invasive neuronal ablation model. We visualize within a single dataset tissue, cellular and subcellular changes which can be quantified in various cell types including neurons and microglia, the brain's macrophages. In addition, nanotomy facilitates the correlation of EM with light microscopy (CLEM)(8) on the same tissue, as large surface areas previously imaged using fluorescent microscopy, can subsequently be subjected to large area EM, resulting in the nano-anatomy (nanotomy) of tissues. In all, nanotomy allows unbiased detection of features at EM level in a tissue-wide quantifiable manner.
Kuipers, Jeroen; Kalicharan, Ruby D.; Wolters, Anouk H. G.
2016-01-01
Large-scale 2D electron microscopy (EM), or nanotomy, is the tissue-wide application of nanoscale resolution electron microscopy. Others and we previously applied large scale EM to human skin pancreatic islets, tissue culture and whole zebrafish larvae1-7. Here we describe a universally applicable method for tissue-scale scanning EM for unbiased detection of sub-cellular and molecular features. Nanotomy was applied to investigate the healthy and a neurodegenerative zebrafish brain. Our method is based on standardized EM sample preparation protocols: Fixation with glutaraldehyde and osmium, followed by epoxy-resin embedding, ultrathin sectioning and mounting of ultrathin-sections on one-hole grids, followed by post staining with uranyl and lead. Large-scale 2D EM mosaic images are acquired using a scanning EM connected to an external large area scan generator using scanning transmission EM (STEM). Large scale EM images are typically ~ 5 - 50 G pixels in size, and best viewed using zoomable HTML files, which can be opened in any web browser, similar to online geographical HTML maps. This method can be applied to (human) tissue, cross sections of whole animals as well as tissue culture1-5. Here, zebrafish brains were analyzed in a non-invasive neuronal ablation model. We visualize within a single dataset tissue, cellular and subcellular changes which can be quantified in various cell types including neurons and microglia, the brain's macrophages. In addition, nanotomy facilitates the correlation of EM with light microscopy (CLEM)8 on the same tissue, as large surface areas previously imaged using fluorescent microscopy, can subsequently be subjected to large area EM, resulting in the nano-anatomy (nanotomy) of tissues. In all, nanotomy allows unbiased detection of features at EM level in a tissue-wide quantifiable manner. PMID:27285162
Getting "Ready" for an Emergency: Emergency Preparedness Series--Part 3
ERIC Educational Resources Information Center
Apel, Laura
2009-01-01
This article presents part 3 of a series of articles giving timely information about potential emergency situations and offering suggestions and new technology that exceptional families can use to prepare for emergencies--everything from localized to large scale emergencies, everything from natural disasters to terrorist attacks. In 2003 the…
Plant succession and approaches to community restoration
Bruce A. Roundy
2005-01-01
The processes of vegetation change over time, or plant succession, are also the processes involved in plant community restoration. Restoration efforts attempt to use designed disturbance, seedbed preparation and sowing methods, and selection of adapted and compatible native plant materials to enhance ecological function. The large scale of wildfires and weed invasion...
Integration of Metal Oxide Nanowires in Flexible Gas Sensing Devices
Comini, Elisabetta
2013-01-01
Metal oxide nanowires are very promising active materials for different applications, especially in the field of gas sensors. Advances in fabrication technologies now allow the preparation of nanowires on flexible substrates, expanding the potential market of the resulting sensors. The critical steps for the large-scale preparation of reliable sensing devices are the elimination of high temperatures processes and the stretchability of the entire final device, including the active material. Direct growth on flexible substrates and post-growth procedures have been successfully used for the preparation of gas sensors. The paper will summarize the procedures used for the preparation of flexible and wearable gas sensors prototypes with an overlook of the challenges and the future perspectives concerning this field. PMID:23955436
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeon, Bup Ju; Hudaya, Chairul; Center for Energy Convergence, Green City Research Institute, Korea Institute of Science and Technology, Hwarangno 14 gil 5, Seoul 136-791
2016-05-15
The authors report the surface morphology, optical, electrical, thermal and humidity impacts, and electromagnetic interference properties of fluorine-doped tin oxide (SnO{sub 2}:F or “FTO”) thin films on a flexible polyethylene terephthalate (PET) substrate fabricated by a pilot-scale electron cyclotron resonance–metal organic chemical vapor deposition (PS ECR-MOCVD). The characteristics of large area FTO thin films were compared with a commercially available transparent conductive electrode made of tin-doped indium oxide (ITO), prepared with an identical film and PET thickness of 125 nm and 188 μm, respectively. The results revealed that the as-prepared FTO thin films exhibited comparable performances with the incumbent ITO films, includingmore » a high optical transmittance of 97% (substrate-subtracted), low electrical resistivity of about 5 × 10{sup −3} Ω cm, improved electrical and optical performances due to the external thermal and humidity impact, and an excellent shielding effectiveness of electromagnetic interference of nearly 2.3 dB. These excellent performances of the FTO thin films were strongly attributed to the design of the PS ECR-MOCVD, which enabled a uniform plasma environment resulting from a proper mixture of electromagnetic profiles and microwave power.« less
Large-scale synthesis of arrays of high-aspect-ratio rigid vertically aligned carbon nanofibres
NASA Astrophysics Data System (ADS)
Melechko, A. V.; McKnight, T. E.; Hensley, D. K.; Guillorn, M. A.; Borisevich, A. Y.; Merkulov, V. I.; Lowndes, D. H.; Simpson, M. L.
2003-09-01
We report on techniques for catalytic synthesis of rigid, high-aspect-ratio, vertically aligned carbon nanofibres by dc plasma enhanced chemical vapour deposition that are tailored for applications that require arrays of individual fibres that feature long fibre lengths (up to 20 µm) such as scanning probe microscopy, penetrant cell and tissue probing arrays and mechanical insertion approaches for gene delivery to cell cultures. We demonstrate that the definition of catalyst nanoparticles is the critical step that enables growth of individual, long-length fibres and discuss methods for catalyst particle preparation that allow the growth of individual isolated nanofibres from catalyst dots with diameters as large as 500 nm. This development enables photolithographic definition of catalyst and therefore the inexpensive, large-scale production of such arrays.
De Vilmorin, Philippe; Slocum, Ashley; Jaber, Tareq; Schaefer, Oliver; Ruppach, Horst; Genest, Paul
2015-01-01
This article describes a four virus panel validation of EMD Millipore's (Bedford, MA) small virus-retentive filter, Viresolve® Pro, using TrueSpike(TM) viruses for a Biogen Idec process intermediate. The study was performed at Charles River Labs in King of Prussia, PA. Greater than 900 L/m(2) filter throughput was achieved with the approximately 8 g/L monoclonal antibody feed. No viruses were detected in any filtrate samples. All virus log reduction values were between ≥3.66 and ≥5.60. The use of TrueSpike(TM) at Charles River Labs allowed Biogen Idec to achieve a more representative scaled-down model and potentially reduce the cost of its virus filtration step and the overall cost of goods. The body of data presented here is an example of the benefits of following the guidance from the PDA Technical Report 47, The Preparation of Virus Spikes Used for Viral Clearance Studies. The safety of biopharmaceuticals is assured through the use of multiple steps in the purification process that are capable of virus clearance, including filtration with virus-retentive filters. The amount of virus present at the downstream stages in the process is expected to be and is typically low. The viral clearance capability of the filtration step is assessed in a validation study. The study utilizes a small version of the larger manufacturing size filter, and a large, known amount of virus is added to the feed prior to filtration. Viral assay before and after filtration allows the virus log reduction value to be quantified. The representativeness of the small-scale model is supported by comparing large-scale filter performance to small-scale filter performance. The large-scale and small-scale filtration runs are performed using the same operating conditions. If the filter performance at both scales is comparable, it supports the applicability of the virus log reduction value obtained with the small-scale filter to the large-scale manufacturing process. However, the virus preparation used to spike the feed material often contains impurities that contribute adversely to virus filter performance in the small-scale model. The added impurities from the virus spike, which are not present at manufacturing scale, compromise the scale-down model and put into question the direct applicability of the virus clearance results. Another consequence of decreased filter performance due to virus spike impurities is the unnecessary over-sizing of the manufacturing system to match the low filter capacity observed in the scale-down model. This article describes how improvements in mammalian virus spike purity ensure the validity of the log reduction value obtained with the scale-down model and support economically optimized filter usage. © PDA, Inc. 2015.
Hookey, Lawrence C; Depew, William T; Vanner, Stephen J
2006-01-01
INTRODUCTION The effectiveness of polyethylene glycol solutions (PEG) for colon cleansing is often limited by the inability of patients to drink adequate portions of the 4 L solution. The aim of the present study was to determine whether a reduced volume of PEG combined with stimulant laxatives would be better tolerated and as or more effective than the standard dose. METHODS Patients undergoing outpatient colonoscopy were randomly assigned to receive either low-volume PEG plus sennosides (120 mg oral sennosides syrup followed by 2 L PEG) or the standard volume preparation (4 L PEG). The subjects rated the tolerability of the preparations and their symptoms. Colonoscopists were blind to the colonic cleansing preparation and graded the cleansing efficacy using a validated tool (the Ottawa scale). RESULTS The low-volume PEG plus sennosides preparation was significantly better tolerated than the standard large volume PEG (P<0.001) but was less efficacious (P=0.03). Thirty-eight per cent of patients in the large volume PEG group were unable to finish the preparation, compared with only 6% in the reduced volume group. There were no adverse events reported. CONCLUSIONS Although the low-volume PEG plus sennosides preparation was better tolerated, it was not as effective as standard large-volume PEG. However, in view of the significant difference in tolerance, further research investigating possible improvements in the reduced-volume regimen seems warranted. PMID:16482236
Evaluation of advanced microelectronics for inclusion in MIL-STD-975
NASA Technical Reports Server (NTRS)
Scott, W. Richard
1991-01-01
The approach taken by NASA and JPL (Jet Propulsion Laboratory) in the development of a MIL-STD-975 section which contains advanced technology such as Large Scale Integration and Very Large Scale Integration (LSI/VLSI) microelectronic devices is described. The parts listed in this section are recommended as satisfactory for NASA flight applications, in the absence of alternate qualified devices, based on satisfactory results of a vendor capability audit, the availability of sufficient characterization and reliability data from the manufacturers and users and negotiated detail procurement specifications. The criteria used in the selection and evaluation of the vendors and candidate parts, the preparation of procurement specifications, and the status of this activity are discussed.
Large-scale Growth and Simultaneous Doping of Molybdenum Disulfide Nanosheets
Kim, Seong Jun; Kang, Min-A; Kim, Sung Ho; Lee, Youngbum; Song, Wooseok; Myung, Sung; Lee, Sun Sook; Lim, Jongsun; An, Ki-Seok
2016-01-01
A facile method that uses chemical vapor deposition (CVD) for the simultaneous growth and doping of large-scale molybdenum disulfide (MoS2) nanosheets was developed. We employed metalloporphyrin as a seeding promoter layer for the uniform growth of MoS2 nanosheets. Here, a hybrid deposition system that combines thermal evaporation and atomic layer deposition (ALD) was utilized to prepare the promoter. The doping effect of the promoter was verified by X-ray photoelectron spectroscopy and Raman spectroscopy. In addition, the carrier density of the MoS2 nanosheets was manipulated by adjusting the thickness of the metalloporphyrin promoter layers, which allowed the electrical conductivity in MoS2 to be manipulated. PMID:27044862
Large-scale terrestrial solar cell power generation cost: A preliminary assessment
NASA Technical Reports Server (NTRS)
Spakowski, A. E.; Shure, L. I.
1972-01-01
A cost study was made to assess the potential of the large-scale use of solar cell power for terrestrial applications. The incentive is the attraction of a zero-pollution source of power for wide-scale use. Unlike many other concepts for low-pollution power generation, even thermal pollution is avoided since only the incident solar flux is utilized. To provide a basis for comparison and a perspective for evaluation, the pertinent technology was treated in two categories: current and optimistic. Factors considered were solar cells, array assembly, power conditioning, site preparation, buildings, maintenance, and operation. The capital investment was assumed to be amortized over 30 years. The useful life of the solar cell array was assumed to be 10 years, and the cases of zero and 50-percent performance deg-radation were considered. Land costs, taxes, and profits were not included in this study because it was found too difficult to provide good generalized estimates of these items. On the basis of the factors considered, it is shown that even for optimistic projections of technology, electric power from large-sclae terrestrial use of solar cells is approximately two to three orders of magnitude more costly than current electric power generation from either fossil or nuclear fuel powerplants. For solar cell power generation to be a viable competitor on a cost basis, technological breakthroughs would be required in both solar cell and array fabrication and in site preparation.
One-step large scale gas phase synthesis of Mn2 + doped ZnS nanoparticles in reducing flames
NASA Astrophysics Data System (ADS)
Athanassiou, E. K.; Grass, R. N.; Stark, W. J.
2010-05-01
Metal sulfide nanoparticles have attracted considerable interest because of their unique semiconducting and electronic properties. In order to prepare these fascinating materials at an industrial scale, however, solvent-free, dry processes would be most advantageous. In the present work, we demonstrate how traditional oxide nanoparticle synthesis in flames can be extended to sulfides if we apply a careful control on flame gas composition and sulfur content. The ultra-fast (<1 ms) gas phase kinetics at elevated temperatures allow direct sulfidization of metals in flames (\\mathrm {MO}_{x} \\Rightarrow \\mathrm {MS}_{x} ). As a representative example, we prepared air-stable Mn2 + doped zinc sulfide nanoparticles. Post-sintering of the initially polycrystalline nanopowder resulted in a material of high crystallinity and improved photoluminescence. An analysis of the thermodynamics, gas composition, and kinetics in these reducing flames indicates that the here-presented extension of flame synthesis provides access to a broad range of metal sulfide nanoparticles and offers an alternative to non-oxide phosphor preparation.
Vapor and healing treatment for CH3NH3PbI3-xClx films toward large-area perovskite solar cells
NASA Astrophysics Data System (ADS)
Gouda, Laxman; Gottesman, Ronen; Tirosh, Shay; Haltzi, Eynav; Hu, Jiangang; Ginsburg, Adam; Keller, David A.; Bouhadana, Yaniv; Zaban, Arie
2016-03-01
Hybrid methyl-ammonium lead trihalide perovskites are promising low-cost materials for use in solar cells and other optoelectronic applications. With a certified photovoltaic conversion efficiency record of 20.1%, scale-up for commercial purposes is already underway. However, preparation of large-area perovskite films remains a challenge, and films of perovskites on large electrodes suffer from non-uniform performance. Thus, production and characterization of the lateral uniformity of large-area films is a crucial step towards scale-up of devices. In this paper, we present a reproducible method for improving the lateral uniformity and performance of large-area perovskite solar cells (32 cm2). The method is based on methyl-ammonium iodide (MAI) vapor treatment as a new step in the sequential deposition of perovskite films. Following the MAI vapor treatment, we used high throughput techniques to map the photovoltaic performance throughout the large-area device. The lateral uniformity and performance of all photovoltaic parameters (Voc, Jsc, Fill Factor, Photo-conversion efficiency) increased, with an overall improved photo-conversion efficiency of ~100% following a vapor treatment at 140 °C. Based on XRD and photoluminescence measurements, We propose that the MAI treatment promotes a ``healing effect'' to the perovskite film which increases the lateral uniformity across the large-area solar cell. Thus, the straightforward MAI vapor treatment is highly beneficial for large scale commercialization of perovskite solar cells, regardless of the specific deposition method.Hybrid methyl-ammonium lead trihalide perovskites are promising low-cost materials for use in solar cells and other optoelectronic applications. With a certified photovoltaic conversion efficiency record of 20.1%, scale-up for commercial purposes is already underway. However, preparation of large-area perovskite films remains a challenge, and films of perovskites on large electrodes suffer from non-uniform performance. Thus, production and characterization of the lateral uniformity of large-area films is a crucial step towards scale-up of devices. In this paper, we present a reproducible method for improving the lateral uniformity and performance of large-area perovskite solar cells (32 cm2). The method is based on methyl-ammonium iodide (MAI) vapor treatment as a new step in the sequential deposition of perovskite films. Following the MAI vapor treatment, we used high throughput techniques to map the photovoltaic performance throughout the large-area device. The lateral uniformity and performance of all photovoltaic parameters (Voc, Jsc, Fill Factor, Photo-conversion efficiency) increased, with an overall improved photo-conversion efficiency of ~100% following a vapor treatment at 140 °C. Based on XRD and photoluminescence measurements, We propose that the MAI treatment promotes a ``healing effect'' to the perovskite film which increases the lateral uniformity across the large-area solar cell. Thus, the straightforward MAI vapor treatment is highly beneficial for large scale commercialization of perovskite solar cells, regardless of the specific deposition method. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr08658b
NASA Astrophysics Data System (ADS)
Soja, Amber; Westberg, David; Stackhouse, Paul, Jr.; McRae, Douglas; Jin, Ji-Zhong; Sukhinin, Anatoly
2010-05-01
Fire is the dominant disturbance that precipitates ecosystem change in boreal regions, and fire is largely under the control of weather and climate. Fire frequency, fire severity, area burned and fire season length are predicted to increase in boreal regions under current climate change scenarios. Therefore, changes in fire regimes have the potential to compel ecological change, moving ecosystems more quickly towards equilibrium with a new climate. The ultimate goal of this research is to assess the viability of large-scale (1°) data to be used to define fire weather danger and fire regimes, so that large-scale data can be confidently used to predict future fire regimes using large-scale fire weather data, like that available from current Intergovernmental Panel on Climate Change (IPCC) climate change scenarios. In this talk, we intent to: (1) evaluate Fire Weather Indices (FWI) derived using reanalysis and interpolated station data; (2) discuss the advantages and disadvantages of using these distinct data sources; and (3) highlight established relationships between large-scale fire weather data, area burned, active fires and ecosystems burned. Specifically, the Canadian Forestry Service (CFS) Fire Weather Index (FWI) will be derived using: (1) NASA Goddard Earth Observing System version 4 (GEOS-4) large-scale reanalysis and NASA Global Precipitation Climatology Project (GPCP) data; and National Climatic Data Center (NCDC) surface station-interpolated data. Requirements of the FWI are local noon surface-level air temperature, relative humidity, wind speed, and daily (noon-noon) rainfall. GEOS-4 reanalysis and NCDC station-interpolated fire weather indices are generally consistent spatially, temporally and quantitatively. Additionally, increased fire activity coincides with increased FWI ratings in both data products. Relationships have been established between large-scale FWI to area burned, fire frequency, ecosystem types, and these can be use to estimate historic and future fire regimes.
DESCRIPTION OF THE ENIAC CONVERTER CODE
The report is intended as a working manual for personnel preparing problems for the ENIAC . It should also serve as a guide to those groups who have...computing problems that could be solved on the ENIAC . The report discusses the ENIAC from the point of view of the coder, describing its memory as well...accomplishes as well as how to use each instruction. A few remarks are made on the more general subject of problem preparation for large scale computers in general based on the experience of operating the ENIAC . (Author)
SERS spectra of pyridine adsorbed on nickel film prepared by magnetron sputtering
NASA Astrophysics Data System (ADS)
Li, Daoyong; Ouyang, Yu; Chen, Li; Cao, Weiran; Shi, Shaohua
2011-02-01
As a repeating well and cheaper enhancement substrate, the nickel film was fabricated with magnetron sputtering coating instrument. Surface enhanced Raman spectra (SERS) of pyridine adsorbed on this nickel film are compared with the experimental values of gaseous pyridine, the theoretical value of pyridine solution listed in other literatures and our method is better than electro-chemical etching electrode method for large scale preparation. The enhancement factor of the nickel film is calculated and the result indicates that magnetron sputtering coating technology is feasible for obtaining good SERS active surface.
Merten, Otto-Wilhelm; Charrier, Sabine; Laroudie, Nicolas; Fauchille, Sylvain; Dugué, Céline; Jenny, Christine; Audit, Muriel; Zanta-Boussif, Maria-Antonietta; Chautard, Hélène; Radrizzani, Marina; Vallanti, Giuliana; Naldini, Luigi; Noguiez-Hellin, Patricia; Galy, Anne
2011-03-01
From the perspective of a pilot clinical gene therapy trial for Wiskott-Aldrich syndrome (WAS), we implemented a process to produce a lentiviral vector under good manufacturing practices (GMP). The process is based on the transient transfection of 293T cells in Cell Factory stacks, scaled up to harvest 50 liters of viral stock per batch, followed by purification of the vesicular stomatitis virus glycoprotein-pseudotyped particles through several membrane-based and chromatographic steps. The process leads to a 200-fold volume concentration and an approximately 3-log reduction in protein and DNA contaminants. An average yield of 13% of infectious particles was obtained in six full-scale preparations. The final product contained low levels of contaminants such as simian virus 40 large T antigen or E1A sequences originating from producer cells. Titers as high as 2 × 10(9) infectious particles per milliliter were obtained, generating up to 6 × 10(11) infectious particles per batch. The purified WAS vector was biologically active, efficiently expressing the genetic insert in WAS protein-deficient B cell lines and transducing CD34(+) cells. The vector introduced 0.3-1 vector copy per cell on average in CD34(+) cells when used at the concentration of 10(8) infectious particles per milliliter, which is comparable to preclinical preparations. There was no evidence of cellular toxicity. These results show the implementation of large-scale GMP production, purification, and control of advanced HIV-1-derived lentiviral technology. Results obtained with the WAS vector provide the initial manufacturing and quality control benchmarking that should be helpful to further development and clinical applications.
University Change in Ireland: Understanding the "What", the "Why" and the "How"
ERIC Educational Resources Information Center
Dowling-Hetherington, Linda
2016-01-01
Over the past decade, universities in Ireland have been implementing large-scale institutional change designed to better prepare them for the multitude of pressures they face. Changes have been taking place, for example, in approaches to institutional management and leadership practices and in decision-making structures. However, despite the rapid…
THE CULTURALLY DEPRIVED. EDUCATING THE DISADVANTAGED.
ERIC Educational Resources Information Center
MITCHELL, CHARLES
AMERICA'S GREAT CITY SCHOOL SYSTEMS ARE HAVING SERIOUS DIFFICULTIES. THEY HAVEN'T ENOUGH MONEY FOR TEACHERS AND CLASSROOMS. THEIR INNER-CITY SCHOOLS ARE CROWDED WITH STUDENTS WHO REQUIRE SERVICES WHICH THE SCHOOLS HAVE NEVER HAD TO PROVIDE ON A LARGE, ORGANIZED SCALE. THEY HAVE TOO FEW TEACHERS, MANY OF WHOM ARE INADEQUATELY PREPARED TO TEACH THE…
Detoxification of Mycotoxins and Other Compounds of Military Interest
1987-01-14
h to A conclusion. A newly recognized naturally occurring gILLathione derivative y ltmlguttin)hs enpnae and methods for large scale preparation of...whereas ochers contained as much as 50-70% of the new material. An effort is currently in progress in order to determine the nature of the new compound
Models of Design: Envisioning a Future Design Education
ERIC Educational Resources Information Center
Friedman, Ken
2012-01-01
This article offers a large-scale view of how design fits in the world economy today, and the role of design education in preparing designers for their economic and professional role. The current context of design involves broad-based historical changes including a major redistribution of geopolitical and industrial power from the West to the…
Behavioral Effects Within and Between Individual and Group Reinforcement Procedures.
ERIC Educational Resources Information Center
Reese, Sandra C.; And Others
This paper briefly outlines the outcomes of a large-scale behavioral program, Preparation through Responsive Educational Programs (PREP), involving students with academic and social deficits from a 1350-student junior high school. Overall program effectiveness was assessed by outcome criteria of total school grades, grades in non-PREP classes,…
Do Sustainability Projects Stimulate Organizational Learning in Universities?
ERIC Educational Resources Information Center
Albrecht, Patrick; Burandt, Simon; Schaltegger, Stefan
2007-01-01
Purpose: The purpose of this paper is to analyze the preparation of a sustainability report and a large-scale energy-saving campaign with regards to their role for organizational learning (OL). Similar processes indicating OL were observed during the implementation of both projects. Along the lines of a theoretical framework of OL these processes…
USDA-ARS?s Scientific Manuscript database
Aqueous slurries of high amylose starch can be steam jet cooked and blended with aqueous solutions of fatty acid salts to generate materials that contain inclusion complexes between amylose and the fatty acid salt. These complexes are simply prepared on large scale using commercially available steam...
Flexible strain sensor based on carbon nanotube rubber composites
NASA Astrophysics Data System (ADS)
Kim, Jin-Ho; Kim, Young-Ju; Baek, Woon Kyung; Lim, Kwon Taek; Kang, Inpil
2010-04-01
Electrically conducting rubber composites (CRC) with carbon nanotubes (CNTs) filler have received much attention as potential materials for sensors. In this work, Ethylene propylene diene M-class rubber (EPDM)/CNT composites as a novel nano sensory material were prepared to develop flexible strain sensors that can measure large deformation of flexible structures. The EPDM/CNT composites were prepared by using a Brabender mixer with multi-walled CNTs and organo-clay. A strain sensor made of EPDM/CNT composite was attached to the surface of a flexible beam and change of resistance of the strain sensor was measured with respect to the beam deflection. Resistance of the sensor was change quite linearly under the bending and compressive large beam deflection. Upon external forces, CRC deformation takes place with the micro scale change of inter-electrical condition in rubber matrix due to the change of contact resistance, and CRC reveals macro scale piezoresistivity. It is anticipated that the CNT/EPDM fibrous strain sensor can be eligible to develop a biomimetic artificial neuron that can continuously sense deformation, pressure and shear force.
NASA Astrophysics Data System (ADS)
Yu, Qing; Huang, Hongwen; Peng, Xinsheng; Ye, Zhizhen
2011-09-01
A simple filtration technique was developed to prepare large scale free-standing close-packed gold nanoparticle ultrathin films using metal hydroxide nanostrands as both barrier layer and sacrificial layer. As thin as 70 nm, centimeter scale robust free-standing gold nanoparticle thin film was obtained. The thickness of the films could be easily tuned by the filtration volumes. The electronic conductivities of these films varied with the size of the gold nanoparticles, post-treatment temperature, and thickness, respectively. The conductivity of the film prepared from 20 nm gold nanoparticles is higher than that of the film prepared from 40 nm gold nanoparticle by filtering the same filtration volume of their solution, respectively. Their conductivities are comparable to that of the 220 nm thick ITO film. Furthermore, these films demonstrated an average surface Raman scattering enhancement up to 6.59 × 105 for Rhodamine 6 G molecules on the film prepared from 40 nm gold nanoparticles. Due to a lot of nano interspaces generated from the close-packed structures, two abnormal enhancements and relative stronger intensities of the asymmetrical vibrations at 1534 and 1594 cm-1 of R6G were observed, respectively. These robust free-standing gold nanoparticle films could be easily transferred onto various solid substrates and hold the potential application for electrodes and surface enhanced Raman detectors. This method is applicable for preparation of other nanoparticle free-standing thin films.A simple filtration technique was developed to prepare large scale free-standing close-packed gold nanoparticle ultrathin films using metal hydroxide nanostrands as both barrier layer and sacrificial layer. As thin as 70 nm, centimeter scale robust free-standing gold nanoparticle thin film was obtained. The thickness of the films could be easily tuned by the filtration volumes. The electronic conductivities of these films varied with the size of the gold nanoparticles, post-treatment temperature, and thickness, respectively. The conductivity of the film prepared from 20 nm gold nanoparticles is higher than that of the film prepared from 40 nm gold nanoparticle by filtering the same filtration volume of their solution, respectively. Their conductivities are comparable to that of the 220 nm thick ITO film. Furthermore, these films demonstrated an average surface Raman scattering enhancement up to 6.59 × 105 for Rhodamine 6 G molecules on the film prepared from 40 nm gold nanoparticles. Due to a lot of nano interspaces generated from the close-packed structures, two abnormal enhancements and relative stronger intensities of the asymmetrical vibrations at 1534 and 1594 cm-1 of R6G were observed, respectively. These robust free-standing gold nanoparticle films could be easily transferred onto various solid substrates and hold the potential application for electrodes and surface enhanced Raman detectors. This method is applicable for preparation of other nanoparticle free-standing thin films. Electronic supplementary information (ESI) available: Figure S1, the SEM images and photograph of the films prepared from 10 ml, 20 nm gold nanoparticles. Scheme S1, the vibrations of 1534 and 1594 cm-1 of R6G. See DOI: 10.1039/c1nr10578g
Synthesis and electrochemical property of few-layer molybdenum disulfide nanosheets
NASA Astrophysics Data System (ADS)
Fu, Yanjue; Wang, Chunrui; Wang, Linlin; Peng, Xia; Wu, Binhe; Sun, Xingqu; Chen, Xiaoshuang
2016-12-01
Large-scale few-layer MoS2 nanosheets have been fabricated via a simple hydrothermal route using molybdenum powder as precursors. The as-prepared MoS2 samples were characterized by X-ray powder diffraction (XRD) analysis, transmission electron microscopy (TEM), and Raman and photoluminescence (PL) spectral analyses at room temperature. The results confirm that the as-prepared MoS2 displays a sheet-like morphology with a thickness of few (bi- to tri-) layers. Electrochemical measurements showed that the as-prepared few-layer MoS2 exhibited the highest reversible capacity of 1127 mAh g-1 and a stable reversible capacity of 1057 mAh g-1 after 30 cycles.
Glovinski, Peter V; Herly, Mikkel; Mathiasen, Anders B; Svalgaard, Jesper D; Borup, Rehannah; Talman, Maj-Lis M; Elberg, Jens J; Kølle, Stig-Frederik T; Drzewiecki, Krzysztof T; Fischer-Nielsen, Anne
2017-02-01
Platelet lysates (PL) represent a promising replacement for xenogenic growth supplement for adipose-derived stem cell (ASC) expansions. However, fresh platelets from human blood donors are not clinically feasible for large-scale cell expansion based on their limited supply. Therefore, we tested PLs prepared via three methods from outdated buffy coat-derived platelet concentrates (PCs) to establish an efficient and feasible expansion of ASCs for clinical use. PLs were prepared by the freeze-thaw method from freshly drawn platelets or from outdated buffy coat-derived PCs stored in the platelet additive solution, InterSol. Three types of PLs were prepared from outdated PCs with platelets suspended in either (1) InterSol (not manipulated), (2) InterSol + supplemented with plasma or (3) plasma alone (InterSol removed). Using these PLs, we compared ASC population doubling time, cell yield, differentiation potential and cell surface markers. Gene expression profiles were analyzed using microarray assays, and growth factor concentrations in the cell culture medium were measured using enzyme-linked immunosorbent assay (ELISA). Of the three PL compositions produced from outdated PCs, removal of Intersol and resuspension in plasma prior to the first freezing process was overall the best. This specific outdated PL induced ASC growth kinetics, surface markers, plastic adherence and differentiation potentials comparable with PL from fresh platelets. ASCs expanded in PL from fresh versus outdated PCs exhibited different expressions of 17 overlapping genes, of which 10 were involved in cellular proliferation, although not significantly reflected by cell growth. Only minor differences in growth factor turnover were observed. PLs from outdated platelets may be an efficient and reliable source of human growth supplement allowing for large-scale ASC expansion for clinical use. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kojima, S.; Yokosawa, M.; Matsuyama, M.
To study the practical application of a tritium separation process using Self-Developing Gas Chromatography (SDGC) using a Pd-Pt alloy, intermediate scale-up experiments (22 mm ID x 2 m length column) and the development of a computational simulation method have been conducted. In addition, intermediate scale production of Pd-Pt powder has been developed for the scale-up experiments.The following results were obtained: (1) a 50-fold scale-up from 3 mm to 22 mm causes no significant impact on the SDGC process; (2) the Pd-Pt alloy powder is applicable to a large size SDGC process; and (3) the simulation enables preparation of a conceptualmore » design of a SDGC process for tritium separation.« less
NASA Technical Reports Server (NTRS)
Hanley, G. M.
1980-01-01
An evolutionary Satellite Power Systems development plan was prepared. Planning analysis was directed toward the evolution of a scenario that met the stated objectives, was technically possible and economically attractive, and took into account constraining considerations, such as requirements for very large scale end-to-end demonstration in a compressed time frame, the relative cost/technical merits of ground testing versus space testing, and the need for large mass flow capability to low Earth orbit and geosynchronous orbit at reasonable cost per pound.
Kulling, Per; Sigurdsson, Susannah; Hamberger, Bertil
2008-01-01
A large-scale armed conflict between Hezbollah and Israel in July 2006 caused the evacuation of a large number of Swedish residents from Lebanon. This report describes the evacuation throughout its various stages. Swedish authorities were prepared for an event of this type from the experience of the 2004 Asian tsunami disaster. Lessons learned from the management and medical care during the evacuations are presented in this report.
Preparation and some properties of Cu-Li alloys containing up to 20 at. % Li
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mendelsohn, M.; Krauss, A.R.; Gruen, D.M.
1985-01-01
Lithium strongly segregates to the surface of Cu-Li alloys, thus substantially lowering the Cu sputtering yield relative to pure Cu. Use of Cu-Li limiters or divertors in tokamaks can therefore be expected to be beneficial in limiting high-Z plasma impurity influx. A large scale (100-200g) method for the preparation of Cu-Li alloys is described. Analysis reveals that on solidification from the melt stratification occurs which leads to compositional inhomogeneity. The results are discussed in the light of the Cu-Li binary phase diagram and rationalized on the basis of large density differences between Cu and Cu-Li solid solutions. It is concludedmore » that obtaining homogeneous Cu-Li solid solutions is a nontrivial task.« less
NASA Astrophysics Data System (ADS)
van der Molen, Johan
2015-04-01
Tidal power generation through submerged turbine-type devices is in an advanced stage of testing, and large-scale applications are being planned in areas with high tidal current speeds. The potential impact of such large-scale applications on the hydrography can be investigated using hydrodynamical models. In addition, aspects of the potential impact on the marine ecosystem can be studied using biogeochemical models. In this study, the coupled hydrodynamics-biogeochemistry model GETM-ERSEM is used in a shelf-wide application to investigate the potential impact of large-scale tidal power generation in the Pentland Firth. A scenario representing the currently licensed power extraction suggested i) an average reduction in M2 tidal current velocities of several cm/s within the Pentland Firth, ii) changes in the residual circulation of several mm/s in the vicinity of the Pentland Firth, iii) an increase in M2 tidal amplitude of up to 1 cm to the west of the Pentland Firth, and iv) a reduction of several mm in M2 tidal amplitude along the east coast of the UK. A second scenario representing 10 times the currently licensed power extraction resulted in changes that were approximately 10 times as large. Simulations including the biogeochemistry model for these scenarios are currently in preparation, and first results will be presented at the the conference, aiming at impacts on primary production and benthic production.
Large-scale time-lapse microscopy of Oct4 expression in human embryonic stem cell colonies.
Bhadriraju, Kiran; Halter, Michael; Amelot, Julien; Bajcsy, Peter; Chalfoun, Joe; Vandecreme, Antoine; Mallon, Barbara S; Park, Kye-Yoon; Sista, Subhash; Elliott, John T; Plant, Anne L
2016-07-01
Identification and quantification of the characteristics of stem cell preparations is critical for understanding stem cell biology and for the development and manufacturing of stem cell based therapies. We have developed image analysis and visualization software that allows effective use of time-lapse microscopy to provide spatial and dynamic information from large numbers of human embryonic stem cell colonies. To achieve statistically relevant sampling, we examined >680 colonies from 3 different preparations of cells over 5days each, generating a total experimental dataset of 0.9 terabyte (TB). The 0.5 Giga-pixel images at each time point were represented by multi-resolution pyramids and visualized using the Deep Zoom Javascript library extended to support viewing Giga-pixel images over time and extracting data on individual colonies. We present a methodology that enables quantification of variations in nominally-identical preparations and between colonies, correlation of colony characteristics with Oct4 expression, and identification of rare events. Copyright © 2016. Published by Elsevier B.V.
Safety Testing of Ammonium Nitrate Based Mixtures
NASA Astrophysics Data System (ADS)
Phillips, Jason; Lappo, Karmen; Phelan, James; Peterson, Nathan; Gilbert, Don
2013-06-01
Ammonium nitrate (AN)/ammonium nitrate based explosives have a lengthy documented history of use by adversaries in acts of terror. While historical research has been conducted on AN-based explosive mixtures, it has primarily focused on detonation performance while varying the oxygen balance between the oxidizer and fuel components. Similarly, historical safety data on these materials is often lacking in pertinent details such as specific fuel type, particle size parameters, oxidizer form, etc. A variety of AN-based fuel-oxidizer mixtures were tested for small-scale sensitivity in preparation for large-scale testing. Current efforts focus on maintaining a zero oxygen-balance (a stoichiometric ratio for active chemical participants) while varying factors such as charge geometry, oxidizer form, particle size, and inert diluent ratios. Small-scale safety testing was conducted on various mixtures and fuels. It was found that ESD sensitivity is significantly affected by particle size, while this is less so for impact and friction. Thermal testing is in progress to evaluate hazards that may be experienced during large-scale testing.
[Development and application of morphological analysis method in Aspergillus niger fermentation].
Tang, Wenjun; Xia, Jianye; Chu, Ju; Zhuang, Yingping; Zhang, Siliang
2015-02-01
Filamentous fungi are widely used in industrial fermentation. Particular fungal morphology acts as a critical index for a successful fermentation. To break the bottleneck of morphological analysis, we have developed a reliable method for fungal morphological analysis. By this method, we can prepare hundreds of pellet samples simultaneously and obtain quantitative morphological information at large scale quickly. This method can largely increase the accuracy and reliability of morphological analysis result. Based on that, the studies of Aspergillus niger morphology under different oxygen supply conditions and shear rate conditions were carried out. As a result, the morphological responding patterns of A. niger morphology to these conditions were quantitatively demonstrated, which laid a solid foundation for the further scale-up.
Production of large-scale, freestanding vanadium pentoxide nanobelt porous structures
NASA Astrophysics Data System (ADS)
Yun, Yong Ju; Kim, Byung Hoon; Hong, Won G.; Kim, Chang Hee; Kim, Yark Yeon; Jeong, Eun-Ju; Jang, Won Ick; Yu, Han Young
2012-02-01
Large-scale, freestanding, porous structures of vanadium pentoxide nanobelts (VPNs) were successfully prepared using the template-free freeze-drying method. The porous and multi-layered VPN macrostructures are composed of randomly oriented long nanobelts (over 100 μm) and their side length can be controlled up to a few tens of centimetres. Also, the bulk density and surface area of these macrostructures are 3-5 mg cm-3 and 40-80 m2 g-1, respectively, which are similar to those of the excellent adsorbents. In addition, the removal efficiency measurements of ammonia molecules revealed that the VPN porous structures can adsorb the ammonia molecules with the combinations of van der Waals forces and strong chemical bonding by functional groups on the VPN surface.
Production of large-scale, freestanding vanadium pentoxide nanobelt porous structures.
Yun, Yong Ju; Kim, Byung Hoon; Hong, Won G; Kim, Chang Hee; Kim, Yark Yeon; Jeong, Eun-ju; Jang, Won Ick; Yu, Han Young
2012-03-07
Large-scale, freestanding, porous structures of vanadium pentoxide nanobelts (VPNs) were successfully prepared using the template-free freeze-drying method. The porous and multi-layered VPN macrostructures are composed of randomly oriented long nanobelts (over 100 μm) and their side length can be controlled up to a few tens of centimetres. Also, the bulk density and surface area of these macrostructures are 3-5 mg cm(-3) and 40-80 m(2) g(-1), respectively, which are similar to those of the excellent adsorbents. In addition, the removal efficiency measurements of ammonia molecules revealed that the VPN porous structures can adsorb the ammonia molecules with the combinations of van der Waals forces and strong chemical bonding by functional groups on the VPN surface.
Impact of a Faith-Based Social Justice Course on Pre-Service Teachers
ERIC Educational Resources Information Center
Critchfield, Meredith
2018-01-01
Rapid demographic shifts are occurring around the country. United States' public schools are more diverse than any time in history. To help prepare pre-service teachers for these shifts, this small-scale qualitative case study explored the impact of a required social justice course for pre-service educators at a large private Christian university…
Changes and Trends in Secondary Agricultural Education in the Czech Republic
ERIC Educational Resources Information Center
Slavik, Milan
2004-01-01
Programmes of education for farmers in the form of Winter Schools, in the early 19th century, were gradually broadened into agricultural education for employment in farming or as preparation for higher education. In the 20th century, vocational education was developed at Apprenticeship and Secondary Schools to meet the needs of large-scale state…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-22
.... Chronic marine pollution stresses fish and wildlife resources, possibly delaying recovery of resources... chronic marine pollution are believed to be at least as important as those of large-scale spills. The... and lower Cook Inlet. The Council seeks to further reduce pollution in the marine environment to...
The Impact of Experiencing a Mobile Game on Teachers' Attitudes towards Mobile Learning
ERIC Educational Resources Information Center
Meishar-Tal, Hagit; Ronen, Miky
2017-01-01
This paper describes a workshop held as part of preparations for a large scale implementation of a mobile game designed to support learning of the topic "my hometown." The study reveals teachers' attitudes towards the incorporation of smartphones in teaching and learning in school and whether these attitudes changed after experiencing…
Experiencing a Mobile Game and Its Impact on Teachers' Attitudes towards Mobile Learning
ERIC Educational Resources Information Center
Meishar-Tal, Hagit; Ronen, Miky
2016-01-01
This paper describes a workshop held as part of preparations for a large scale implementation of a mobile game designed to support learning of the topic "my hometown". The study reveals teachers' attitudes towards the incorporation of smartphones in teaching and learning in school and whether these attitudes changed after experiencing…
Lanxing Du; Jinwu Wang; Yang Zhang; Chusheng Qi; Michael P. Wolcott; Zhiming Yu
2017-01-01
This study demonstrated the technical potential for the large-scale co-production of sugars, lignosulfonates, cellulose, and cellulose nanocrystals. Ball-milled woods with two particle sizes were prepared by ball milling for 80 min or 120 min (BMW80, BMW120) and then enzymatically hydrolyzed. 78.3% cellulose conversion of...
Learning and Teaching Technology in English Teacher Education: Findings from a National Study
ERIC Educational Resources Information Center
Pasternak, Donna L.; Hallman, Heidi L.; Caughlan, Samantha; Renzi, Laura; Rush, Leslie S.; Meineke, Hannah
2016-01-01
This paper reports on one aspect of a large-scale nationwide study that surveyed English teacher educators about English teacher preparation programs throughout the United States. One aspect of the study focused on how technology is integrated within the context of English teacher education programs, asking the question, "As an area of…
On the Brink: Activity and Resource Guide to Teaching about Massachusetts Endangered Species.
ERIC Educational Resources Information Center
Cervoni, Cleti, Ed.
Project WILD is the first large-scale curriculum supplement focusing on wildlife concepts and integrated with many areas of the general school curriculum. It features decision-making processes and explores a diversity of attitudes toward wildlife. The goal of Project WILD is to prepare young people to make decisions affecting people and wildlife…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fishkind, H.H.
The silvicultural matrix within which the nation's first large scale wood energy plantation will develop is described in detail. The relevant literature reviewed is identified and distilled. The plantation history, site preparation, planting, species selection, maintenance and management, harvesting, and the Eucalyptus biomass production estimates are presented.
A NASTRAN Model of a Large Flexible Swing-Wing Bomber. Volume 1: NASTRAN Model Plane
NASA Technical Reports Server (NTRS)
Mock, W. D.
1982-01-01
A review was conducted of B-1 aircraft no. 2 (A/C-2) internal loads models to determine the minimum model complexity necessary to fulfill all of the airloads research study objectives. Typical model sizings were tabulated at selected vehicle locations, and scale layouts were prepared of the NASTRAN structural analysis model.
The Role of Empathy in Preparing Teachers to Tackle Bullying
ERIC Educational Resources Information Center
Murphy, Helena; Tubritt, John; Norman, James O'Higgins
2018-01-01
Much research on bullying behaviour in schools among students has been carried out since the 1970's, when Olweus started a large-scale project in Norway which is now generally regarded as the first scientific study on bullying. Yet, there has been little research on how teachers respond to reports of bullying and tackle bullying behaviour in…
WikiTextbooks: Designing Your Course around a Collaborative Writing Project
ERIC Educational Resources Information Center
Katz, Brian P.; Thoren, Elizabeth
2014-01-01
We have used wiki technology to support large-scale, collaborative writing projects in which the students build reference texts (called WikiTextbooks). The goal of this paper is to prepare readers to adapt this idea for their own courses. We give examples of the implementation of WikiTextbooks in a variety of courses, including lecture and…
Cheng, Jing-Jy; Chao, Chi-Hsein; Lu, Mei-Kuang
2018-07-01
Sulfated polysaccharides (SPSs) were isolated from 0.5mM potassium-sulfate fed Antrodia cinnamomea. We investigated the chemical properties and bio-activities of the five different fractions (SPS-K1, SPS-K2, SPS-K3, SPS-K4, and SPS-K5) with molecular weights ranging from 0.51 to 523.48kDa. SPS-K3 was consisted mainly of glucose, galactose and sulfate in a molar ratio of 15:1:30 with Mn value of 6.82kDa. It showed maximal inhibition of the tumor necrosis factor (TNF-α), interleukin-1beta (IL-1β) and interleukin-6 (IL-6) on bacterial LPS-induced inflammation in RAW264.7 macrophage and the production was recorded as 26.19 and 51.06%, respectively. SPS-K2 showed inhibition of endothelial cell tube formation in an in vitro assay of angiogenesis, and IC 50 was determined to be 160.92μg/ml. Large-scale preparation of SPS was performed in the 3-L fermentation of A. cinnamomea and the yield of the SPS was 5.38%. The area percentage of high-molecular-weight SPSs (1470-1590kDa) covered almost half of the SPSs mixture characterized by size exclusion column chromatography. The SPSs from fermented A. cinnamomea had significant inhibition on TNF-α, IL-1β and IL-6 production. This study is the first report to large-scale produce SPSs and demonstrates sulfated galactoglucan with strong anti-inflammatory activity. Copyright © 2018 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Cai, Xing-Wei; Zhao, Yu-Yuan; Li, Hong; Huang, Cui-Ping; Zhou, Zhen
2018-06-01
With the flourishing development of emitting materials, tremendous technological progress has been accomplished. However, they still face great challenges in convenient economical environmental-friendly large-scale commercial production. Herein we designed this organic-inorganic hybrid lead-free compound, an emerging class of high-efficiency emitting materials, [(C10H16N)2][MnBr4] (1), which emits intense greenish photoluminescence with a high emissive quantum yields of 72.26%, was prepared through the convenient economical solution method. What's more, compared with rare earth fluorescent materials (especially green-emitting Tb), Mn material is rich in natural resources and low commercial cost, which would possess an increasingly predominant advantage in the preparation of luminescent materials. Additionally, the exceptional thermal stability as well as the low-cost/convenient preparation process makes crystal 1 with the large size of more than 1 cm to be an ideal technologically important green-emitting material and it would open up a new route towards the commercialization process of lead-free/rare earth-free hybrid emitting materials in display and sensing.
Preparation of highly multiplexed small RNA sequencing libraries.
Persson, Helena; Søkilde, Rolf; Pirona, Anna Chiara; Rovira, Carlos
2017-08-01
MicroRNAs (miRNAs) are ~22-nucleotide-long small non-coding RNAs that regulate the expression of protein-coding genes by base pairing to partially complementary target sites, preferentially located in the 3´ untranslated region (UTR) of target mRNAs. The expression and function of miRNAs have been extensively studied in human disease, as well as the possibility of using these molecules as biomarkers for prognostication and treatment guidance. To identify and validate miRNAs as biomarkers, their expression must be screened in large collections of patient samples. Here, we develop a scalable protocol for the rapid and economical preparation of a large number of small RNA sequencing libraries using dual indexing for multiplexing. Combined with the use of off-the-shelf reagents, more samples can be sequenced simultaneously on large-scale sequencing platforms at a considerably lower cost per sample. Sample preparation is simplified by pooling libraries prior to gel purification, which allows for the selection of a narrow size range while minimizing sample variation. A comparison with publicly available data from benchmarking of miRNA analysis platforms showed that this method captures absolute and differential expression as effectively as commercially available alternatives.
Research on the self-absorption corrections for PGNAA of large samples
NASA Astrophysics Data System (ADS)
Yang, Jian-Bo; Liu, Zhi; Chang, Kang; Li, Rui
2017-02-01
When a large sample is analysed with the prompt gamma neutron activation analysis (PGNAA) neutron self-shielding and gamma self-absorption affect the accuracy, the correction method for the detection efficiency of the relative H of each element in a large sample is described. The influences of the thickness and density of the cement samples on the H detection efficiency, as well as the impurities Fe2O3 and SiO2 on the prompt γ ray yield for each element in the cement samples, were studied. The phase functions for Ca, Fe, and Si on H with changes in sample thickness and density were provided to avoid complicated procedures for preparing the corresponding density or thickness scale for measuring samples under each density or thickness value and to present a simplified method for the measurement efficiency scale for prompt-gamma neutron activation analysis.
Identification of Phosphorylated Proteins on a Global Scale.
Iliuk, Anton
2018-05-31
Liquid chromatography (LC) coupled with tandem mass spectrometry (MS/MS) has enabled researchers to analyze complex biological samples with unprecedented depth. It facilitates the identification and quantification of modifications within thousands of proteins in a single large-scale proteomic experiment. Analysis of phosphorylation, one of the most common and important post-translational modifications, has particularly benefited from such progress in the field. Here, detailed protocols are provided for a few well-regarded, common sample preparation methods for an effective phosphoproteomic experiment. © 2018 by John Wiley & Sons, Inc. Copyright © 2018 John Wiley & Sons, Inc.
Casting Control of Floating-films into Ribbon-shape Structure by modified Dynamic FTM
NASA Astrophysics Data System (ADS)
Tripathi, A.; Pandey, M.; Nagamatsu, S.; Pandey, S. S.; Hayase, S.; Takashima, W.
2017-11-01
We have developed a new method to obtain Ribbon-shaped floating films via dynamic casting of floating-film and transfer method (dynamic-FTM). Dynamic-FTM is a unique method to prepare oriented thin-film of conjugated polymers (CPs) which is quick and easy. This method has several advantages as compared to the other conventional casting procedure to prepare oriented CP films. In the conventional dynamic FTM appearance of large scale circular orientation poses difficulty not only for practical applications but also hinders the detailed analysis of the orientation mechanism. In this present work, pros and cons of this newly proposed ribbon-shaped floating-film have been discussed in detail from those of the conventional floating-film prepared by dynamic-FTM.
Novel approach for extinguishing large-scale coal fires using gas-liquid foams in open pit mines.
Lu, Xinxiao; Wang, Deming; Qin, Botao; Tian, Fuchao; Shi, Guangyi; Dong, Shuaijun
2015-12-01
Coal fires are a serious threat to the workers' security and safe production in open pit mines. The coal fire source is hidden and innumerable, and the large-area cavity is prevalent in the coal seam after the coal burned, causing the conventional extinguishment technology difficult to work. Foams are considered as an efficient means of fire extinguishment in these large-scale workplaces. A noble foam preparation method is introduced, and an original design of cavitation jet device is proposed to add foaming agent stably. The jet cavitation occurs when the water flow rate and pressure ratio reach specified values. Through self-building foaming system, the high performance foams are produced and then infused into the blast drilling holes at a large flow. Without complicated operation, this system is found to be very suitable for extinguishing large-scale coal fires. Field application shows that foam generation adopting the proposed key technology makes a good fire extinguishment effect. The temperature reduction using foams is 6-7 times higher than water, and CO concentration is reduced from 9.43 to 0.092‰ in the drilling hole. The coal fires are controlled successfully in open pit mines, ensuring the normal production as well as the security of personnel and equipment.
Weis, Karen L; Lederman, Regina P; Walker, Katherine C; Chan, Wenyaw
To determine the efficacy of the Mentors Offering Maternal Support (MOMS) program to reduce pregnancy-specific anxiety and depression and build self-esteem and resilience in military women. Randomized controlled trial with repeated measures. Large military community in Texas. Pregnant women (N = 246) in a military sample defined as active duty or spouse of military personnel. Participants were randomized in the first trimester to the MOMS program or normal prenatal care. Participants attended eight 1-hour sessions every other week during the first, second, and third trimesters of pregnancy. Pregnancy-specific anxiety, depression, self-esteem, and resilience were measured in each trimester. Linear mixed models were used to compare the two-group difference in slope for prenatal anxiety, depression, self-esteem, and resilience. The Prenatal Self-Evaluation Questionnaire was used to measure perinatal anxiety. Rates of prenatal anxiety on the Identification With a Motherhood Role (p = .049) scale and the Preparation for Labor (p = .017) scale were significantly reduced for participants in MOMS. Nulliparous participants showed significantly lower anxiety on the Acceptance of Pregnancy scale and significantly greater anxiety on the Preparation for Labor scale. Single participants had significantly greater anxiety on the Well-Being of Self and Baby in Labor scale, and participants with deployed husbands had significantly greater anxiety on the Identification With a Motherhood Role scale. Participation in the MOMS program reduced pregnancy-specific prenatal anxiety for the dimensions of Identification With a Motherhood Role and Preparation for Labor. Both dimensions of anxiety were previously found to be significantly associated with preterm birth and low birth weight. Military leaders have recognized the urgent need to support military families. Copyright © 2017 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses. Published by Elsevier Inc. All rights reserved.
Shinde, Manish; Patil, Rajendra; Karmakar, Soumen; Bhoraskar, Sudha; Rane, Sunit; Gade, Wasudev; Amalnerkar, Dinesh
2012-02-01
We, herein, report the antimicrobial properties of uncapped silver nanoparticles for a Gram positive model organism, Bacillus subtilis. Uncapped silver nanoparticles have been prepared using less-explored DC arc thermal plasma technique by considering its large scale generation capability. It is observed that the resultant nanoparticles show size as well as optical property dependent antimicrobial effect.
ERIC Educational Resources Information Center
Dyson, Benjamin; Vickers, Kristin; Turtle, John; Cowan, Sara; Tassone, Adrianna
2015-01-01
Both lecture delivery and Facebook use are ubiquitous aspects of higher education from staff and student points-of-view, respectively. An attempt was made to integrate the two by setting up a Facebook group and delivering contemporary news stories in preparation for in-lecture discussion in a large-scale (1,200 students across 5 sections)…
Ultrahydrophobic Fluorinated Polyhedral Oligomeric Silsesquioxanes (F-POSS) (Preprint)
2007-01-25
From - To) 25-01-2007 Journal Article 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Ultrahydrophobic Fluorinated Polyhedral Oligomeric Silsesquioxanes...Ultrahydrophobic Fluorinated Polyhedral Oligomeric Silsesquioxanes (F-POSS) Joseph M. Mabry,* Ashwani Vij,* Scott T. Iacono, and Brent D. Viers Recently...there exists a demand to construct ultrahydrophobic materials inspired by nature that are easy to prepare on a large scale. Polyhedral oligomeric
ERIC Educational Resources Information Center
Towndrow, Phillip; Kwek, Dennis Beng Kiat
2017-01-01
Set against the backdrop of reinvigorating the study of literature and concerns about the adequate preparation of students for the world of work, this paper explores how a Singapore teacher presented a literary text in the classroom. Drawing on data from a large-scale representative sample of Singapore schools in instruction and assessment…
Tyrosine Phosphorylation of Botulinum Neurotoxin Protease Domains
2012-06-01
trifluoroacetic acid; Tm: melting temperature; TMB, 3,3′,5,5′-tetramethylbenzidine; UPLC , ultra performance liquid chromatography; VAMP, vesicle...activity determination by UPLC . Alternately, in large-scale preparations, phosphoryla- tion reaction was stopped by removing the Src with sepharose beads...peptides. ENZYMATIC ACTIVITY ASSAYS Activity assays were based on UPLC separation and measurement of the cleaved products from a 17-residue SNAP-25
ERIC Educational Resources Information Center
Iwashita, Noriko
2006-01-01
The study reported in this article is a part of a large-scale study investigating syntactic complexity in second language (L2) oral data in commonly taught foreign languages (English, German, Japanese, and Spanish; Ortega, Iwashita, Rabie, & Norris, in preparation). In this article, preliminary findings of the analysis of the Japanese data are…
Climate-induced changes in vulnerability to biological threats in the southern United States
Rabiu Olatinwo; Qinfeng Guo; Songlin Fei; William Otrosina; Kier Klepzig; Douglas Streett
2014-01-01
Forest land managers face the challenges of preparing their forests for the impacts of climate change. However, climate change adds a new dimension to the task of developing and testing science-based management options to deal with the effects of stressors on forest ecosystems in the southern United States. The large spatial scale and complex interactions make...
Amine enriched solid sorbents for carbon dioxide capture
Gray, McMahan L.; Soong, Yee; Champagne, Kenneth J.
2003-04-15
A new method for making low-cost CO.sub.2 sorbents that can be used in large-scale gas-solid processes. The new method entails treating a solid substrate with acid or base and simultaneous or subsequent treatment with a substituted amine salt. The method eliminates the need for organic solvents and polymeric materials for the preparation of CO.sub.2 capture systems.
USDA-ARS?s Scientific Manuscript database
This study reports generation of large-scale genomic resources for pigeonpea, a so-called ‘orphan crop species’ of the semi-arid tropic regions. Roche FLX/454 sequencing was carried out on a normalized cDNA pool prepared from 31 tissues produced 494,353 short transcript reads (STRs). Cluster analysi...
Field experiences in pre-commercial thinning, planting and container growing of northern softwoods
L. Oscar Selin
1977-01-01
In preparation for intensive logging mechanization and for the subsequent silvicultural treatments of clearcut areas the Woodland Division of Georgia-Pacific Corporation started a pre-commercial thinning trials in young softwood and mixed wood stands during the spring and early summer of 1970. Pre-commercial thinnings were intended to be a backbone of a large scale...
VizieR Online Data Catalog: REFLEX Galaxy Cluster Survey catalogue (Boehringer+, 2004)
NASA Astrophysics Data System (ADS)
Boehringer, H.; Schuecker, P.; Guzzo, L.; Collins, C. A.; Voges, W.; Cruddace, R. G.; Ortiz-Gil, A.; Chincarini, G.; de Grandi, S.; Edge, A. C.; MacGillivray, H. T.; Neumann, D. M.; Schindler, S.; Shaver, P.
2004-05-01
The following tables provide the catalogue as well as several data files necessary to reproduce the sample preparation. These files are also required for the cosmological modeling of these observations in e.g. the study of the statistics of the large-scale structure of the matter distribution in the Universe and related cosmological tests. (13 data files).
ERIC Educational Resources Information Center
Greene, Jay; Loveless, Tom; MacLeod, W. Bentley; Nechyba, Thomas; Peterson, Paul; Rosenthal, Meredith; Whitehurst, Grover
2010-01-01
Choice is most frequently realized within the public sector using the mechanisms of residence, magnet schools, and open enrollment systems, whereas the voucher-like systems applauded by choice advocates and feared by opponents are extremely rare. Further, the charter sector is neither large enough nor sufficiently prepared to go to scale to…
ERIC Educational Resources Information Center
Martin, Catherine Anne
2017-01-01
This study, "Teacher Insight: The Implementation of the Common Core State Standards in California School Districts" was designed to glean teacher voice on the large-scale reform. With a need for a global workforce in a 21st century society the existing education system is undergoing a tremendous change in order to prepare students for…
Ultrafast and large scale preparation of superior catalyst for oxygen evolution reaction
NASA Astrophysics Data System (ADS)
Tian, Xianqing; Liu, Yunhua; Xiao, Dan; Sun, Jie
2017-10-01
The development of efficient and earth abundant catalyst for the oxygen evolution reaction (OER) is a key challenge for the renewable energy research community. Here, we report a facile and ultrafast route to immobilize nickel-iron layered double hydroxide (NiFe-LDH) nanoparticles on nickel foam (NF) via soaking the direct electroless deposited prussian blue analogue (PBA) on NF in 1 M KOH. This NiFe-LDH/NF electrode can be prepared in a few seconds without further treatments. It has three-dimensional interpenetrating network originated from its PBA precursor which facilitate the diffusion and ad/desorption of the reactants and producing for OER. And further characterization of the Faradaic efficiency and forced convection tests show direct evidence to demonstrate the formation of free intermediate(s) in the OER process. This electrode (typically NiFe-LDH-20s/NF) exhibits outstanding electrocatalytic activity with low overpotential of ∼0.240 V at 10 mA cm-2, low Tafel slope of 38 mV dec-1, and great stability. This feasible strategy affords a new strategy for the large scale manufacture of low-cost, effective and robust OER electrodes.
Ren, Zhonghua; Li, Jianpeng; Ren, Yaqi; Wang, Shuguang; Qiu, Yejun; Yu, Jie
2016-01-01
Electrochemical performance and production cost are the main concerns for the practical application of supercapacitors. Here we report a simple and universally applicable method to prepare hybrid metal oxides by metal redox reaction utilizing the inherent reducibility of metals and oxidbility of for the first time. As an example, Ni(OH)2/MnO2 hybrid nanosheets (NMNSs) are grown for supercapacitor application by self-reaction of Ni foam substrates in KMnO4 solution at room temperature. The obtained hybrid nanosheets exhibit high specific capacitance (2,937 F g−1). The assembled solid-state asymmetric pseudocapacitors possess ultrahigh energy density of 91.13 Wh kg−1 (at the power density of 750 W kg−1) and extraordinary cycling stability with 92.28% capacitance retention after 25,000 cycles. Co(OH)2/MnO2 and Fe2O3/MnO2 hybrid oxides are also synthesized through this metal redox mechanism. This green and low-cost method is capable of large-scale production and one-step preparation of the electrodes, holding promise for practical application of high-performance pseudocapacitors. PMID:26805027
Yu, Qing; Huang, Hongwen; Peng, Xinsheng; Ye, Zhizhen
2011-09-01
A simple filtration technique was developed to prepare large scale free-standing close-packed gold nanoparticle ultrathin films using metal hydroxide nanostrands as both barrier layer and sacrificial layer. As thin as 70 nm, centimeter scale robust free-standing gold nanoparticle thin film was obtained. The thickness of the films could be easily tuned by the filtration volumes. The electronic conductivities of these films varied with the size of the gold nanoparticles, post-treatment temperature, and thickness, respectively. The conductivity of the film prepared from 20 nm gold nanoparticles is higher than that of the film prepared from 40 nm gold nanoparticle by filtering the same filtration volume of their solution, respectively. Their conductivities are comparable to that of the 220 nm thick ITO film. Furthermore, these films demonstrated an average surface Raman scattering enhancement up to 6.59 × 10(5) for Rhodamine 6 G molecules on the film prepared from 40 nm gold nanoparticles. Due to a lot of nano interspaces generated from the close-packed structures, two abnormal enhancements and relative stronger intensities of the asymmetrical vibrations at 1534 and 1594 cm(-1) of R6G were observed, respectively. These robust free-standing gold nanoparticle films could be easily transferred onto various solid substrates and hold the potential application for electrodes and surface enhanced Raman detectors. This method is applicable for preparation of other nanoparticle free-standing thin films.
The synthesis of active pharmaceutical ingredients (APIs) using continuous flow chemistry
2015-01-01
Summary The implementation of continuous flow processing as a key enabling technology has transformed the way we conduct chemistry and has expanded our synthetic capabilities. As a result many new preparative routes have been designed towards commercially relevant drug compounds achieving more efficient and reproducible manufacture. This review article aims to illustrate the holistic systems approach and diverse applications of flow chemistry to the preparation of pharmaceutically active molecules, demonstrating the value of this strategy towards every aspect ranging from synthesis, in-line analysis and purification to final formulation and tableting. Although this review will primarily concentrate on large scale continuous processing, additional selected syntheses using micro or meso-scaled flow reactors will be exemplified for key transformations and process control. It is hoped that the reader will gain an appreciation of the innovative technology and transformational nature that flow chemistry can leverage to an overall process. PMID:26425178
Rogers, R; Sewell, K W; Morey, L C; Ustad, K L
1996-12-01
Psychological assessment with multiscale inventories is largely dependent on the honesty and forthrightness of those persons evaluated. We investigated the effectiveness of the Personality Assessment Inventory (PAI) in detecting participants feigning three specific disorders: schizophrenia, major depression, and generalized anxiety disorder. With a simulation design, we tested the PAI validity scales on 166 naive (undergraduates with minimal preparation) and 80 sophisticated (doctoral psychology students with 1 week preparation) participants. We compared their results to persons with the designated disorders: schizophrenia (n = 45), major depression (n = 136), and generalized anxiety disorder (n = 40). Although moderately effective with naive simulators, the validity scales evidenced only modest positive predictive power with their sophisticated counterparts. Therefore, we performed a two-stage discriminant analysis that yielded a moderately high hit rate (> 80%) that was maintained in the cross-validation sample, irrespective of the feigned disorder or the sophistication of the simulators.
Ikigai, H; Seki, K; Nishihara, S; Masuda, S
1988-01-01
A simplified method for preparation of concentrated exoproteins including protein A and alpha-toxin produced by Staphylococcus aureus was successfully devised. The concentrated proteins were obtained by cultivating S. aureus organisms on the surface of a liquid medium-containing cellophane bag enclosed in a sterilized glass flask. With the same amount of medium, the total amount of proteins obtained by the method presented here was identical with that obtained by conventional liquid culture. The concentration of proteins obtained by the method, however, was high enough to observe their distinct bands stained on polyacrylamide gel electrophoresis. This method was considered quite useful not only for large-scale cultivation for the purification of staphylococcal proteins but also for small-scale study using the proteins. The precise description of the method was presented and its possible usefulness was discussed.
The synthesis of active pharmaceutical ingredients (APIs) using continuous flow chemistry.
Baumann, Marcus; Baxendale, Ian R
2015-01-01
The implementation of continuous flow processing as a key enabling technology has transformed the way we conduct chemistry and has expanded our synthetic capabilities. As a result many new preparative routes have been designed towards commercially relevant drug compounds achieving more efficient and reproducible manufacture. This review article aims to illustrate the holistic systems approach and diverse applications of flow chemistry to the preparation of pharmaceutically active molecules, demonstrating the value of this strategy towards every aspect ranging from synthesis, in-line analysis and purification to final formulation and tableting. Although this review will primarily concentrate on large scale continuous processing, additional selected syntheses using micro or meso-scaled flow reactors will be exemplified for key transformations and process control. It is hoped that the reader will gain an appreciation of the innovative technology and transformational nature that flow chemistry can leverage to an overall process.
NASA Astrophysics Data System (ADS)
Bundschuh, V.; Grueter, J. W.; Kleemann, M.; Melis, M.; Stein, H. J.; Wagner, H. J.; Dittrich, A.; Pohlmann, D.
1982-08-01
A preliminary study was undertaken before a large scale project for construction and survey of about a hundred solar houses was launched. The notion of solar house was defined and the use of solar energy (hot water preparation, heating of rooms, heating of swimming pool, or a combination of these possibilities) were examined. A coherent measuring program was set up. Advantages and inconveniences of the large scale project were reviewed. Production of hot water, evaluation of different concepts and different fabrications of solar systems, coverage of the different systems, conservation of energy, failure frequency and failures statistics, durability of the installation, investment maintenance and energy costs were retained as study parameters. Different solar hot water production systems and the heat counter used for measurements are described.
2'-modified nucleosides for site-specific labeling of oligonucleotides
NASA Technical Reports Server (NTRS)
Krider, Elizabeth S.; Miller, Jeremiah E.; Meade, Thomas J.
2002-01-01
We report the synthesis of 2'-modified nucleosides designed specifically for incorporating labels into oligonucleotides. Conversion of these nucleosides to phosphoramidite and solid support-bound derivatives proceeds in good yield. Large-scale synthesis of 11-mer oligonucleotides possessing the 2'-modified nucleosides is achieved using these derivatives. Thermal denaturation studies indicate that the presence of 2'-modified nucleosides in 11-mer duplexes has minimal destabilizing effects on the duplex structure when the nucleosides are placed at the duplex termini. The powerful combination of phosphoramidite and support-bound derivatives of 2'-modified nucleosides affords the large-scale preparation of an entirely new class of oligonucleotides. The ability to synthesize oligonucleotides containing label attachment sites at 3', intervening, and 5' locations of a duplex is a significant advance in the development of oligonucleotide conjugates.
Shirshekanb, Mahsa; Rezadoost, Hassan; Javanbakht, Mehran; Ghassempour, Ali Reza
2017-01-01
There is no other naturally occurring defense agent against cancer that has a stronger effect than paclitaxel, commonly known under the brand name of Taxol ® . The major drawback for the more widespread use of paclitaxel and its precious precursor, 10-deacetylbaccatin III (10-DAB III), is that they require large-scale extraction from different parts of yew trees ( Taxus species), cell cultures, taxane-producing endophytic fungi, and Corylus species. In our previous work, a novel online two-dimensional heart-cut liquid chromatography process using hydrophilic interaction/ reversed-phase chromatography was used to introduce a semi-preparative treatment for the separation of polar (10-deacetylbaccatin III) and non-polar (paclitaxel) taxanes from Taxus baccata L. In this work, a combination of the absorbent (Diaion ® HP-20) and a silica based solid phase extraction is utilized as a new, efficient, and cost effective method for large-scale production of taxanes. This process avoids the technical problem of two-dimensional preparative liquid chromatography. The first stage of the process involves discarding co-extractive polar compounds including chlorophylls and pigments using a non-polar synthetic hydrophobic absorbent, Diaion ® HP-20. Extract was then loaded on to a silica based hydrophilic interaction solid phase extraction (silica 40-60 micron). Taxanes was eluted using a mixture of water and methanol at the optimized ratio of 70:30. Finally, the fraction containing taxanes was applied to semi-preparative reversed phase HPLC. The results revealed that using this procedure, paclitaxel and 10-DAB III could be obtained at 8 and 3 times more, respectively than by the traditional method of extraction.
The Galics Project: Virtual Galaxy: from Cosmological N-body Simulations
NASA Astrophysics Data System (ADS)
Guiderdoni, B.
The GalICS project develops extensive semi-analytic post-processing of large cosmological simulations to describe hierarchical galaxy formation. The multiwavelength statistical properties of high-redshift and local galaxies are predicted within the large-scale structures. The fake catalogs and mock images that are generated from the outputs are used for the analysis and preparation of deep surveys. The whole set of results is now available in an on-line database that can be easily queried. The GalICS project represents a first step towards a 'Virtual Observatory of virtual galaxies'.
Carbonized-leaf Membrane with Anisotropic Surfaces for Sodium-ion Battery.
Li, Hongbian; Shen, Fei; Luo, Wei; Dai, Jiaqi; Han, Xiaogang; Chen, Yanan; Yao, Yonggang; Zhu, Hongli; Fu, Kun; Hitz, Emily; Hu, Liangbing
2016-01-27
A simple one-step thermal pyrolysis route has been developed to prepare carbon membrane from a natural leaf. The carbonized leaf membrane possesses anisotropic surfaces and internal hierarchical porosity, exhibiting a high specific capacity of 360 mAh/g and a high initial Coulombic efficiency of 74.8% as a binder-free, current-collector-free anode for rechargeable sodium ion batteries. Moreover, large-area carbon membranes with low contact resistance are fabricated by simply stacking and carbonizing leaves, a promising strategy toward large-scale sodium-ion battery developments.
Chen, Fei-Fei; Yang, Zi-Yue; Zhu, Ying-Jie; Xiong, Zhi-Chao; Dong, Li-Ying; Lu, Bing-Qiang; Wu, Jin; Yang, Ri-Long
2018-01-09
To date, the scaled-up production and large-area applications of superhydrophobic coatings are limited because of complicated procedures, environmentally harmful fluorinated compounds, restrictive substrates, expensive equipment, and raw materials usually involved in the fabrication process. Herein, the facile, low-cost, and green production of superhydrophobic coatings based on hydroxyapatite nanowire bundles (HNBs) is reported. Hydrophobic HNBs are synthesised by using a one-step solvothermal method with oleic acid as the structure-directing and hydrophobic agent. During the reaction process, highly hydrophobic C-H groups of oleic acid molecules can be attached in situ to the surface of HNBs through the chelate interaction between Ca 2+ ions and carboxylic groups. This facile synthetic method allows the scaled-up production of HNBs up to about 8 L, which is the largest production scale of superhydrophobic paint based on HNBs ever reported. In addition, the design of the 100 L reaction system is also shown. The HNBs can be coated on any substrate with an arbitrary shape by the spray-coating technique. The self-cleaning ability in air and oil, high-temperature stability, and excellent mechanical durability of the as-prepared superhydrophobic coatings are demonstrated. More importantly, the HNBs are coated on large-sized practical objects to form large-area superhydrophobic coatings. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Lu, Yao; Xu, Wenji; Song, Jinlong; Liu, Xin; Xing, Yingjie; Sun, Jing
2012-12-01
The preparation of superhydrophobic surfaces on hydrophilic metal substrates depends on both surface microstructures and low surface energy modification. In this study, a simple and inexpensive electrochemical method for preparing robust superhydrophobic titanium surfaces is reported. The neutral sodium chloride solution is used as electrolyte. Fluoroalkylsilane (FAS) was used to reduce the surface energy of the electrochemically etched surface. Scanning electron microscopy (SEM) images, energy-dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) spectra, and contact angle measurement are performed to characterize the morphological features, chemical composition, and wettability of the titanium surfaces. Stability and friction tests indicate that the prepared titanium surfaces are robust. The analysis of electrolyte, reaction process, and products demonstrates that the electrochemical processing is very inexpensive and environment-friendly. This method is believed to be easily adaptable for use in large-scale industry productions to promote the application of superhydrophobic titanium surfaces in aviation, aerospace, shipbuilding, and the military industry.
NASA Astrophysics Data System (ADS)
Subramanian, Sunu; Pandurangan, Arumugam
2016-04-01
The challenges on carbon nanotubes and graphene are still the subject of many research works due to its unique properties. There are three main methods to synthesis carbon nanotubes in which chemical vapor deposition (CVD) method can use for large scale production. The principle of CVD is the decomposition of various hydrocarbons over transition metal supported catalyst. KIT-6 molecular sieve was used as a support to prepare cobalt catalyst for CVD method using metal impregnation method to produce cobalt loadings of 2, 4 and 6 wt%. The catalysts were characterized by XRD, FTIR &TEM. Carbon nanotubes (CNTs) synthesized on Co-KIT-6 was also characterized by XRD, TGA, SEM & Raman spectra. Graphene was synthesized by Hummers method, which is the most common method for preparing graphene oxide. Graphene oxide was prepared by oxidation of graphite using some oxidizing agents like sulphuric acid, sodium nitrate and potassium permanganate. This graphene oxide is further treated with hydrazine solution to convert it into chemically converted graphene and also decorated with nickel metal and characterized. Hummer's method is important for large scale production of graphene. Both Graphene and carbon nanotubes are used in different fields due to its unique properties. Both Graphene and carbon nanotubes are fabricated in counter electrode of Dye sensitized solar cells (DSSC). By cyclic voltammetry study, it confirms that both materials are good and efficient to replace platinum in the DSSC.
Purification and preparation of graphite oxide from natural graphite
DOE Office of Scientific and Technical Information (OSTI.GOV)
Panatarani, C., E-mail: c.panatarani@phys.unpad.ac.id; Muthahhari, N.; Joni, I. Made
2016-03-11
Graphite oxide has attracted much interest as a possible route for preparation of natural graphite in the large-scale production and manipulation of graphene as a material with extraordinary electronic properties. Graphite oxide was prepared by modified Hummers method from purified natural graphite sample from West Kalimantan. We demonstrated that natural graphite is well-purified by acid leaching method. The purified graphite was proceed for intercalating process by modifying Hummers method. The modification is on the reaction time and temperature of the intercalation process. The materials used in the intercalating process are H{sub 2}SO{sub 4} and KMNO{sub 4}. The purified natural graphitemore » is analyzed by carbon content based on Loss on Ignition test. The thermo gravimetricanalysis and the Fouriertransform infrared spectroscopy are performed to investigate the oxidation results of the obtained GO which is indicated by the existence of functional groups. In addition, the X-ray diffraction and energy dispersive X-ray spectroscopy are also applied to characterize respectively for the crystal structure and elemental analysis. The results confirmed that natural graphite samples with 68% carbon content was purified into 97.68 % carbon content. While the intercalation process formed a formation of functional groups in the obtained GO. The results show that the temperature and reaction times have improved the efficiency of the oxidation process. It is concluded that these method could be considered as an important route for large-scale production of graphene.« less
Spin diffusion from an inhomogeneous quench in an integrable system.
Ljubotina, Marko; Žnidarič, Marko; Prosen, Tomaž
2017-07-13
Generalized hydrodynamics predicts universal ballistic transport in integrable lattice systems when prepared in generic inhomogeneous initial states. However, the ballistic contribution to transport can vanish in systems with additional discrete symmetries. Here we perform large scale numerical simulations of spin dynamics in the anisotropic Heisenberg XXZ spin 1/2 chain starting from an inhomogeneous mixed initial state which is symmetric with respect to a combination of spin reversal and spatial reflection. In the isotropic and easy-axis regimes we find non-ballistic spin transport which we analyse in detail in terms of scaling exponents of the transported magnetization and scaling profiles of the spin density. While in the easy-axis regime we find accurate evidence of normal diffusion, the spin transport in the isotropic case is clearly super-diffusive, with the scaling exponent very close to 2/3, but with universal scaling dynamics which obeys the diffusion equation in nonlinearly scaled time.
Cheng, Chen; Guironnet, Damien; Barborak, James; Brookhart, Maurice
2011-06-29
Conjugated polymers possessing a poly(2,5-dimethylene-2,5-dihydrofuran) backbone were prepared through postpolymerization reaction of styrenic polyketones with bromine in one-pot reactions. The modification is proposed to proceed via condensation of two repeating units to form a fully characterized polymer with a poly(2,5-dimethylenetetrahydrofuran) backbone. Subsequent bromination and elimination of HBr yield a polymer with a fully conjugated carbon backbone. The new conjugated polymers were characterized by NMR, IR, and UV-vis spectroscopies and by CV. These polymers have strong absorption in the visible region, with the absorption peaks shifted to the NIR region upon doping with acids. The ease of the synthesis of the starting polyketone and of the modifications allows large-scale preparation of those conjugated polymers.
NASA Astrophysics Data System (ADS)
Zhen, Fangchen; Ran, Maofei; Chu, Wei; Jiang, Chengfa; Sun, Wenjing
2018-03-01
Pd-Fe3O4 hybrid nanostructures were prepared using a simple one-pot hydrothermal method. The prepared materials were characterized by Fourier transform-infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma, N2 adsorption-desorption, and vibrating sample magnetometry. This self-assembled nanosystem acted as an efficient magnetically recyclable noble metal-based multi-functional nanocatalyst. It showed excellent catalytic activity and stability for the Heck reaction of iodobenzene and styrene under mild conditions. The methods used to prepare the Pd-Fe3O4 catalysts were simple and low-cost, which will be useful for the large-scale development and application of a magnetically recoverable Pd catalyst.
A facile and green preparation of reduced graphene oxide using Eucalyptus leaf extract
NASA Astrophysics Data System (ADS)
Li, Chengyang; Zhuang, Zechao; Jin, Xiaoying; Chen, Zuliang
2017-11-01
In this paper, a green and facile synthesis of reduced graphene oxide (GO) by Eucalyptus leaf extract (EL-RGO) was investigated, which was characterized with ultraviolet-visible spectroscopy (UV), Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and Thermal gravimetric analysis (TG). Eucalyptus leaf extract also play both reducing and capping stabilizing agents prepared EL-RGO as shown a good stability and electrochemical properties. This approach could provide an alternative method to prepare EL-RGO in large-scale production. Moreover, the good electrochemical property and biocompatibility can be used in various applications. In addition, the merit of this study is that both the oxidized products and the reducing agents are environmental friendly by green reduction.
Preparation and Thermoelectric Properties of Graphite/Bi0.5Sb1.5Te3 Composites
NASA Astrophysics Data System (ADS)
Hu, Wenhua; Zhou, Hongyu; Mu, Xin; He, Danqi; Ji, Pengxia; Hou, Weikang; Wei, Ping; Zhu, Wanting; Nie, Xiaolei; Zhao, Wenyu
2018-06-01
Bismuth telluride zone-melting alloys are the most commercially used thermoelectric materials. However, the zone-melting ingots have weak machinability due to the strong preferred orientation. Here, non-textured graphite/Bi0.5Sb1.5Te3 (G/BST) composites were prepared by a powder metallurgy method combined with cold-pressing and annealing treatments. The composition, microstructure, and thermoelectric properties of the G/BST composites with different mass percentages of G were investigated. It was found that G addition could effectively reduce the thermal conductivity and slightly improve the electrical properties of the BST, which resulted in a large enhancement in the figure-of-merit, ZT. The largest ZT for the xG/BST composites with x = 0.05% reached 1.05 at 320 K, which is increased by 35% as compared with that of the G-free BST materials. This work provided an effective method for preparing non-textured Bi2Te3-based TE materials with a simple process, low cost, and large potential in scale production.
Preparing Laboratory and Real-World EEG Data for Large-Scale Analysis: A Containerized Approach
Bigdely-Shamlo, Nima; Makeig, Scott; Robbins, Kay A.
2016-01-01
Large-scale analysis of EEG and other physiological measures promises new insights into brain processes and more accurate and robust brain–computer interface models. However, the absence of standardized vocabularies for annotating events in a machine understandable manner, the welter of collection-specific data organizations, the difficulty in moving data across processing platforms, and the unavailability of agreed-upon standards for preprocessing have prevented large-scale analyses of EEG. Here we describe a “containerized” approach and freely available tools we have developed to facilitate the process of annotating, packaging, and preprocessing EEG data collections to enable data sharing, archiving, large-scale machine learning/data mining and (meta-)analysis. The EEG Study Schema (ESS) comprises three data “Levels,” each with its own XML-document schema and file/folder convention, plus a standardized (PREP) pipeline to move raw (Data Level 1) data to a basic preprocessed state (Data Level 2) suitable for application of a large class of EEG analysis methods. Researchers can ship a study as a single unit and operate on its data using a standardized interface. ESS does not require a central database and provides all the metadata data necessary to execute a wide variety of EEG processing pipelines. The primary focus of ESS is automated in-depth analysis and meta-analysis EEG studies. However, ESS can also encapsulate meta-information for the other modalities such as eye tracking, that are increasingly used in both laboratory and real-world neuroimaging. ESS schema and tools are freely available at www.eegstudy.org and a central catalog of over 850 GB of existing data in ESS format is available at studycatalog.org. These tools and resources are part of a larger effort to enable data sharing at sufficient scale for researchers to engage in truly large-scale EEG analysis and data mining (BigEEG.org). PMID:27014048
Microfluidic desalination techniques and their potential applications.
Roelofs, S H; van den Berg, A; Odijk, M
2015-09-07
In this review we discuss recent developments in the emerging research field of miniaturized desalination. Traditionally desalination is performed to convert salt water into potable water and research is focused on improving performance of large-scale desalination plants. Microfluidic desalination offers several new opportunities in comparison to macro-scale desalination, such as providing a platform to increase fundamental knowledge of ion transport on the nano- and microfluidic scale and new microfluidic sample preparation methods. This approach has also lead to the development of new desalination techniques, based on micro/nanofluidic ion-transport phenomena, which are potential candidates for up-scaling to (portable) drinking water devices. This review assesses microfluidic desalination techniques on their applications and is meant to contribute to further implementation of microfluidic desalination techniques in the lab-on-chip community.
NASA Astrophysics Data System (ADS)
Roh, H. S.; Kang, Y. C.; Park, H. D.; Park, S. B.
Y2O3:Eu phosphor particles were prepared by large-scale spray pyrolysis. The morphological control of Y2O3:Eu particles in spray pyrolysis was attempted by adding polymeric precursors to the spray solution. The effect of composition and amount of polymeric precursors on the morphology, crystallinity and photoluminescence characteristics of Y2O3:Eu particles was investigated. Particles prepared from a solution containing polyethylene glycol (PEG) with an average molecular weight of 200 had a hollow structure, while those prepared from solutions containing adequate amounts of citric acid (CA) and PEG had a spherical shape, filled morphology and clean surfaces after post-treatment at high temperature. Y2O3:Eu particles prepared from an aqueous solution with no polymeric precursors had a hollow structure and rough surfaces after post-treatment. The phosphor particles prepared from solutions with inadequate amounts of CA and/or PEG also had hollow and/or fragmented structures. The particles prepared from the solution containing 0.3 M CA and 0.3 M PEG had the highest photoluminescence emission intensity, which was 56% higher than that of the particles prepared from aqueous solution without polymeric precursors.
Preparation of Copper (Cu)-Nickel (Ni) Alloy Thin Films for Bilayer Graphene Growth
2016-02-01
public release; distribution is unlimited. 5 0 50 100 150 200 250 300 350 40 60 80 100 In te ns ity 2 Theta (°) 6:1 Cu/Ni, 15 mT, 400°C...JY, Hong BH. Large-scale pattern growth of graphene films for stretchable transparent electrodes. Nature. 2009;457:706−710 4. Li XS , Cai WW, An JH
Quantum information processing with long-wavelength radiation
NASA Astrophysics Data System (ADS)
Murgia, David; Weidt, Sebastian; Randall, Joseph; Lekitsch, Bjoern; Webster, Simon; Navickas, Tomas; Grounds, Anton; Rodriguez, Andrea; Webb, Anna; Standing, Eamon; Pearce, Stuart; Sari, Ibrahim; Kiang, Kian; Rattanasonti, Hwanjit; Kraft, Michael; Hensinger, Winfried
To this point, the entanglement of ions has predominantly been performed using lasers. Using long wavelength radiation with static magnetic field gradients provides an architecture to simplify construction of a large scale quantum computer. The use of microwave-dressed states protects against decoherence from fluctuating magnetic fields, with radio-frequency fields used for qubit manipulation. I will report the realisation of spin-motion entanglement using long-wavelength radiation, and a new method to efficiently prepare dressed-state qubits and qutrits, reducing experimental complexity of gate operations. I will also report demonstration of ground state cooling using long wavelength radiation, which may increase two-qubit entanglement fidelity. I will then report demonstration of a high-fidelity long-wavelength two-ion quantum gate using dressed states. Combining these results with microfabricated ion traps allows for scaling towards a large scale ion trap quantum computer, and provides a platform for quantum simulations of fundamental physics. I will report progress towards the operation of microchip ion traps with extremely high magnetic field gradients for multi-ion quantum gates.
Modeling the Hydrologic Effects of Large-Scale Green Infrastructure Projects with GIS
NASA Astrophysics Data System (ADS)
Bado, R. A.; Fekete, B. M.; Khanbilvardi, R.
2015-12-01
Impervious surfaces in urban areas generate excess runoff, which in turn causes flooding, combined sewer overflows, and degradation of adjacent surface waters. Municipal environmental protection agencies have shown a growing interest in mitigating these effects with 'green' infrastructure practices that partially restore the perviousness and water holding capacity of urban centers. Assessment of the performance of current and future green infrastructure projects is hindered by the lack of adequate hydrological modeling tools; conventional techniques fail to account for the complex flow pathways of urban environments, and detailed analyses are difficult to prepare for the very large domains in which green infrastructure projects are implemented. Currently, no standard toolset exists that can rapidly and conveniently predict runoff, consequent inundations, and sewer overflows at a city-wide scale. We demonstrate how streamlined modeling techniques can be used with open-source GIS software to efficiently model runoff in large urban catchments. Hydraulic parameters and flow paths through city blocks, roadways, and sewer drains are automatically generated from GIS layers, and ultimately urban flow simulations can be executed for a variety of rainfall conditions. With this methodology, users can understand the implications of large-scale land use changes and green/gray storm water retention systems on hydraulic loading, peak flow rates, and runoff volumes.
Ding, Fuchuan; Liu, Jingjing; Zeng, Songshan; Xia, Yan; Wells, Kacie M.; Nieh, Mu-Ping; Sun, Luyi
2017-01-01
Large-scale biomimetic organic/inorganic hybrid nanocoatings with a nacre-like microstructure were prepared via a facile coassembly process. Different from conventional polymer nanocomposites, these nanocoatings contain a high concentration of nanosheets, which can be well aligned along the substrate surface. Moreover, the nanosheets and polymer matrix can be chemically co–cross-linked. As a result, the nanocoatings exhibit exceptional mechanical properties (high stiffness and strength), barrier properties (to both oxygen and water vapor), and flame retardancy, but they are also highly transparent (maintaining more than 85% of their original transmittance to visible light). The nanocoatings can be applied to various substrates and regular or irregular surfaces (for example, films and foams). Because of their excellent performance and high versatility, these nanocoatings are expected to find widespread application. PMID:28776038
Large-scale synthesis of a novel tri(8-hydroxyquioline) aluminum nanostructure.
Tian, Xike; Fei, Jinbo; Pi, Zhenbang; Yang, Chao; Xiao, Zhidong; Zhang, Lide
2006-08-01
A novel tri(8-hydroxyquioline) aluminum (AlQ3) nanostructure was prepared on large scale at low cost by low-temperature physical vapor deposition (PVD). The morphologies, the chemical bondings, and photoluminescence of the AlQ3 nanostructure were investigated by environmental scanning electronic microscopy (ESEM), Fourier transform infrared spectrum (FT-IR), and photoluminescence (PL) spectra, respectively. The AlQ3 nanostructure was composed of micro-sphere with nanowire-cluster growing on the surface. The diameter of micro-sphere and nanowire were about 5 microm and 80 nm, respectively. FT-IR results indicated that the AlQ3 molecule had a strong thermal stability under research conditions. The growth mechanism of the novel nanostructure was discussed. The novel organic nanostructure would be believed to attractive building field-emission devices and other optical devices.
The LHC magnet system and its status of development
NASA Technical Reports Server (NTRS)
Bona, Maurizio; Perin, Romeo; Vlogaert, Jos
1995-01-01
CERN is preparing for the construction of a new high energy accelerator/collider, the Large Hadron Collider (LHC). This new facility will mainly consist of two superconducting magnetic beam channels, 27 km long, to be installed in the existing LEP tunnel. The magnetic system comprises about 1200 twin-aperture dipoles, 13.145 m long, with an operational field of 8.65 T, about 600 quadrupoles, 3 m long, and a very large number of other superconducting magnetic components. A general description of the system is given together with the main features of the design of the regular lattice magnets. The paper also describes the present state of the magnet R & D program. Results from short model work, as well as from full scale prototypes will be presented, including the recently tested 10 m long full-scale prototype dipole manufactured in industry.
USDA-ARS?s Scientific Manuscript database
Proper identification of soft scales (Hemiptera:Coccidae) requires preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare soft scale specimens on microscope slides for examination and identification. Steps ranging from collection, speci...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spittler, T.E.; Sydnor, R.H.; Manson, M.W.
1990-01-01
The Loma Prieta earthquake of October 17, 1989 triggered landslides throughout the Santa Cruz Mountains in central California. The California Department of Conservation, Division of Mines and Geology (DMG) responded to a request for assistance from the County of Santa Cruz, Office of Emergency Services to evaluate the geologic hazard from major reactivated large landslides. DMG prepared a set of geologic maps showing the landslide features that resulted from the October 17 earthquake. The principal purpose of large-scale mapping of these landslides is: (1) to provide county officials with regional landslide information that can be used for timely recovery ofmore » damaged areas; (2) to identify disturbed ground which is potentially vulnerable to landslide movement during winter rains; (3) to provide county planning officials with timely geologic information that will be used for effective land-use decisions; (4) to document regional landslide features that may not otherwise be available for individual site reconstruction permits and for future development.« less
Polymeric materials from renewable resources
NASA Astrophysics Data System (ADS)
Frollini, Elisabete; Rodrigues, Bruno V. M.; da Silva, Cristina G.; Castro, Daniele O.; Ramires, Elaine C.; de Oliveira, Fernando; Santos, Rachel P. O.
2016-05-01
The goals of our studies have been the use of renewable raw materials in the preparation of polymeric materials with diversified properties. In this context, lignosulfonate, which is produced in large scale around the world, but not widely used in the production of polymeric materials, was used to replace phenol and polyols in the preparation of phenolic- (Ligno-PH) and polyurethane-type (Ligno-PU) polymers, respectively. These polymers were used to prepare composites reinforced with sisal lignocellulosic fibers. The use of lignosulfonate in the formulation of both types of polymers was beneficial, because in general composites with improved properties, specially impact strength, were obtained. Composites were also prepared from the so called "biopolyethylene" (HDPE), curaua lignocellulosic fiber, and castor oil (CO). All composites HDBPE/CO/Fiber exhibited higher impact strength, when compared to those of the corresponding HDBPE/Fiber. These results, combined with others (eg SEM images of the fractured surfaces) indicated that, in addition to acting as a plasticizer, this oil may have acted as a compatibilizer of the hydrophilic fiber with the hydrophobic polymer. The set of results indicated that (i) mats with nano (diameter ≤ 100nm) and/or ultrafine (submicron scale) fibers were produced, (ii) hybrid fibers were produced (bio-based mats composites), (iii) cellulosic pulp (CP) and/or lignin (Lig) can be combined with PET matrices to control properties such as stiffness and hydrophilicity of the respective mats. Materials with diversified properties were prepared from high content of renewable raw materials, thus fulfilling the proposed targets.
On the statistical mechanics of the 2D stochastic Euler equation
NASA Astrophysics Data System (ADS)
Bouchet, Freddy; Laurie, Jason; Zaboronski, Oleg
2011-12-01
The dynamics of vortices and large scale structures is qualitatively very different in two dimensional flows compared to its three dimensional counterparts, due to the presence of multiple integrals of motion. These are believed to be responsible for a variety of phenomena observed in Euler flow such as the formation of large scale coherent structures, the existence of meta-stable states and random abrupt changes in the topology of the flow. In this paper we study stochastic dynamics of the finite dimensional approximation of the 2D Euler flow based on Lie algebra su(N) which preserves all integrals of motion. In particular, we exploit rich algebraic structure responsible for the existence of Euler's conservation laws to calculate the invariant measures and explore their properties and also study the approach to equilibrium. Unexpectedly, we find deep connections between equilibrium measures of finite dimensional su(N) truncations of the stochastic Euler equations and random matrix models. Our work can be regarded as a preparation for addressing the questions of large scale structures, meta-stability and the dynamics of random transitions between different flow topologies in stochastic 2D Euler flows.
Li, Jinsong; Lu, Weibang; Suhr, Jonghwan; Chen, Hang; Xiao, John Q; Chou, Tsu-Wei
2017-05-24
Graphene has sparked extensive research interest for its excellent physical properties and its unique potential for application in absorption of electromagnetic waves. However, the processing of stable large-scale graphene and magnetic particles on a micrometer-thick conductive support is a formidable challenge for achieving high reflection loss and impedance matching between the absorber and free space. Herein, a novel and simple approach for the processing of a CNT film-Fe 3 O 4 -large scale graphene composite is studied. The Fe 3 O 4 particles with size in the range of 20-200 nm are uniformly aligned along the axial direction of the CNTs. The composite exhibits exceptionally high wave absorption capacity even at a very low thickness. Minimum reflection loss of -44.7 dB and absorbing bandwidth of 4.7 GHz at -10 dB are achieved in composites with one-layer graphene in six-layer CNT film-Fe 3 O 4 prepared from 0.04 M FeCl 3 . Microstructural and theoretical studies of the wave-absorbing mechanism reveal a unique Debye dipolar relaxation with an Eddy current effect in the absorbing bandwidth.
Lunar terrain mapping and relative-roughness analysis
NASA Technical Reports Server (NTRS)
Rowan, L. C.; Mccauley, J. F.; Holm, E. A.
1971-01-01
Terrain maps of the equatorial zone were prepared at scales of 1:2,000,000 and 1:1,000,000 to classify lunar terrain with respect to roughness and to provide a basis for selecting sites for Surveyor and Apollo landings, as well as for Ranger and Lunar Orbiter photographs. Lunar terrain was described by qualitative and quantitative methods and divided into four fundamental classes: maria, terrae, craters, and linear features. Some 35 subdivisions were defined and mapped throughout the equatorial zone, and, in addition, most of the map units were illustrated by photographs. The terrain types were analyzed quantitatively to characterize and order their relative roughness characteristics. For some morphologically homogeneous mare areas, relative roughness can be extrapolated to the large scales from measurements at small scales.
USDA-ARS?s Scientific Manuscript database
Proper identification of armored scales (Hemiptera: Diaspididae) requires preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare armored scales specimens on microscope slides for examination and identification. Steps ranging from collect...
Zhang, Yong-Gang; Zhu, Ying-Jie; Xiong, Zhi-Chao; Wu, Jin; Chen, Feng
2018-04-18
Inorganic aerogels have been attracting great interest owing to their distinctive structures and properties. However, the practical applications of inorganic aerogels are greatly restricted by their high brittleness and high fabrication cost. Herein, inspired by the cancellous bone, we have developed a novel kind of hydroxyapatite (HAP) nanowire-based inorganic aerogel with excellent elasticity, which is highly porous (porosity ≈ 99.7%), ultralight (density 8.54 mg/cm 3 , which is about 0.854% of water density), and highly adiabatic (thermal conductivity 0.0387 W/m·K). Significantly, the as-prepared HAP nanowire aerogel can be used as the highly efficient air filter with high PM 2.5 filtration efficiency. In addition, the HAP nanowire aerogel is also an ideal candidate for continuous oil-water separation, which can be used as a smart switch to separate oil from water continuously. Compared with organic aerogels, the as-prepared HAP nanowire aerogel is biocompatible, environmentally friendly, and low-cost. Moreover, the synthetic method reported in this work can be scaled up for large-scale production of HAP nanowires, free from the use of organic solvents. Therefore, the as-prepared new kind of HAP nanowire aerogel is promising for the applications in various fields.
Cho, Jung Sang; Ju, Hyeon Seok; Kang, Yun Chan
2016-01-01
A commercially applicable and simple process for the preparation of aggregation-free metal oxide hollow nanospheres is developed by applying nanoscale Kirkendall diffusion to a large-scale spray drying process. The precursor powders prepared by spray drying are transformed into homogeneous metal oxide hollow nanospheres through a simple post-treatment process. Aggregation-free SnO2 hollow nanospheres are selected as the first target material for lithium ion storage applications. Amorphous carbon microspheres with uniformly dispersed Sn metal nanopowder are prepared in the first step of the post-treatment process under a reducing atmosphere. The post-treatment of the Sn-C composite powder at 500 °C under an air atmosphere produces carbon- and aggregation-free SnO2 hollow nanospheres through nanoscale Kirkendall diffusion. The hollow and filled SnO2 nanopowders exhibit different cycling performances, with their discharge capacities after 300 cycles being 643 and 280 mA h g−1, respectively, at a current density of 2 A g−1. The SnO2 hollow nanospheres with high structural stability exhibit superior cycling and rate performances for lithium ion storage compared to the filled ones. PMID:27033088
NASA Astrophysics Data System (ADS)
Cho, Jung Sang; Ju, Hyeon Seok; Kang, Yun Chan
2016-04-01
A commercially applicable and simple process for the preparation of aggregation-free metal oxide hollow nanospheres is developed by applying nanoscale Kirkendall diffusion to a large-scale spray drying process. The precursor powders prepared by spray drying are transformed into homogeneous metal oxide hollow nanospheres through a simple post-treatment process. Aggregation-free SnO2 hollow nanospheres are selected as the first target material for lithium ion storage applications. Amorphous carbon microspheres with uniformly dispersed Sn metal nanopowder are prepared in the first step of the post-treatment process under a reducing atmosphere. The post-treatment of the Sn-C composite powder at 500 °C under an air atmosphere produces carbon- and aggregation-free SnO2 hollow nanospheres through nanoscale Kirkendall diffusion. The hollow and filled SnO2 nanopowders exhibit different cycling performances, with their discharge capacities after 300 cycles being 643 and 280 mA h g-1, respectively, at a current density of 2 A g-1. The SnO2 hollow nanospheres with high structural stability exhibit superior cycling and rate performances for lithium ion storage compared to the filled ones.
The use of smoke acid as an alternative coagulating agent for natural rubber sheets' production.
Ferreira, Vanda S; Rêgo, Ione N C; Pastore, Floriano; Mandai, Mariana M; Mendes, Leonardo S; Santos, Karin A M; Rubim, Joel C; Suarez, Paulo A Z
2005-03-01
A comparative study of rubber sheets obtained using formic, acetic, and smoke acid as coagulants is shown for latex obtained from native Amazonian trees and also from commercial cultivated trees. The evaluation of both processes of coagulation was carried out by spectroscopic and physical-chemical analysis, showing no differences in the rubber sheets obtained. This new method of rubber sheet preparation was introduced into Amazonian rainforest rubber tapper communities, which are actually producing in large scale. The physical-mechanical properties were similar among a large sheets made by different rubber tapper communities using this new method.
Validation of the RAGE Hydrocode for Impacts into Volatile-Rich Targets
NASA Astrophysics Data System (ADS)
Plesko, C. S.; Asphaug, E.; Coker, R. F.; Wohletz, K. H.; Korycansky, D. G.; Gisler, G. R.
2007-12-01
In preparation for a detailed study of large-scale impacts into the Martian surface, we have validated the RAGE hydrocode (Gittings et al., in press, CSD) against a suite of experiments and statistical models. We present comparisons of hydrocode models to centimeter-scale gas gun impacts (Nakazawa et al. 2002), an underground nuclear test (Perret, 1971), and crater scaling laws (Holsapple 1993, O'Keefe and Ahrens 1993). We have also conducted model convergence and uncertainty analyses which will be presented. Results to date are encouraging for our current model goals, and indicate areas where the hydrocode may be extended in the future. This validation work is focused on questions related to the specific problem of large impacts into volatile-rich targets. The overall goal of this effort is to be able to realistically model large-scale Noachian, and possibly post- Noachian, impacts on Mars not so much to model the crater morphology as to understand the evolution of target volatiles in the post-impact regime, to explore how large craters might set the stage for post-impact hydro- geologic evolution both locally (in the crater subsurface) and globally, due to the redistribution of volatiles from the surface and subsurface into the atmosphere. This work is performed under the auspices of IGPP and the DOE at LANL under contracts W-7405-ENG-36 and DE-AC52-06NA25396. Effort by DK and EA is sponsored by NASA's Mars Fundamental Research Program.
Sundramoorthy, Ashok K.; Wang, Yilei; Wang, Jing; Che, Jianfei; Thong, Ya Xuan; Lu, Albert Chee W.; Chan-Park, Mary B.
2015-01-01
Graphene is a promising candidate material for transparent conductive films because of its excellent conductivity and one-carbon-atom thickness. Graphene oxide flakes prepared by Hummers method are typically several microns in size and must be pieced together in order to create macroscopic films. We report a macro-scale thin film fabrication method which employs a three-dimensional (3-D) surfactant, 4-sulfocalix[4]arene (SCX), as a lateral aggregating agent. After electrochemical exfoliation, the partially oxidized graphene (oGr) flakes are dispersed with SCX. The SCX forms micelles, which adsorb on the oGr flakes to enhance their dispersion, also promote aggregation into large-scale thin films under vacuum filtration. A thin oGr/SCX film can be shaved off from the aggregated oGr/SCX cake by immersing the cake in water. The oGr/SCX thin-film floating on the water can be subsequently lifted from the water surface with a substrate. The reduced oGr (red-oGr) films can be as thin as 10−20 nm with a transparency of >90% and sheet resistance of 890 ± 47 kΩ/sq. This method of electrochemical exfoliation followed by SCX-assisted suspension and hydrazine reduction, avoids using large amounts of strong acid (unlike Hummers method), is relatively simple and can easily form a large scale conductive and transparent film from oGr/SCX suspension. PMID:26040436
A robust quantitative near infrared modeling approach for blend monitoring.
Mohan, Shikhar; Momose, Wataru; Katz, Jeffrey M; Hossain, Md Nayeem; Velez, Natasha; Drennen, James K; Anderson, Carl A
2018-01-30
This study demonstrates a material sparing Near-Infrared modeling approach for powder blend monitoring. In this new approach, gram scale powder mixtures are subjected to compression loads to simulate the effect of scale using an Instron universal testing system. Models prepared by the new method development approach (small-scale method) and by a traditional method development (blender-scale method) were compared by simultaneously monitoring a 1kg batch size blend run. Both models demonstrated similar model performance. The small-scale method strategy significantly reduces the total resources expended to develop Near-Infrared calibration models for on-line blend monitoring. Further, this development approach does not require the actual equipment (i.e., blender) to which the method will be applied, only a similar optical interface. Thus, a robust on-line blend monitoring method can be fully developed before any large-scale blending experiment is viable, allowing the blend method to be used during scale-up and blend development trials. Copyright © 2017. Published by Elsevier B.V.
Constructing Flexible, Configurable, ETL Pipelines for the Analysis of "Big Data" with Apache OODT
NASA Astrophysics Data System (ADS)
Hart, A. F.; Mattmann, C. A.; Ramirez, P.; Verma, R.; Zimdars, P. A.; Park, S.; Estrada, A.; Sumarlidason, A.; Gil, Y.; Ratnakar, V.; Krum, D.; Phan, T.; Meena, A.
2013-12-01
A plethora of open source technologies for manipulating, transforming, querying, and visualizing 'big data' have blossomed and matured in the last few years, driven in large part by recognition of the tremendous value that can be derived by leveraging data mining and visualization techniques on large data sets. One facet of many of these tools is that input data must often be prepared into a particular format (e.g.: JSON, CSV), or loaded into a particular storage technology (e.g.: HDFS) before analysis can take place. This process, commonly known as Extract-Transform-Load, or ETL, often involves multiple well-defined steps that must be executed in a particular order, and the approach taken for a particular data set is generally sensitive to the quantity and quality of the input data, as well as the structure and complexity of the desired output. When working with very large, heterogeneous, unstructured or semi-structured data sets, automating the ETL process and monitoring its progress becomes increasingly important. Apache Object Oriented Data Technology (OODT) provides a suite of complementary data management components called the Process Control System (PCS) that can be connected together to form flexible ETL pipelines as well as browser-based user interfaces for monitoring and control of ongoing operations. The lightweight, metadata driven middleware layer can be wrapped around custom ETL workflow steps, which themselves can be implemented in any language. Once configured, it facilitates communication between workflow steps and supports execution of ETL pipelines across a distributed cluster of compute resources. As participants in a DARPA-funded effort to develop open source tools for large-scale data analysis, we utilized Apache OODT to rapidly construct custom ETL pipelines for a variety of very large data sets to prepare them for analysis and visualization applications. We feel that OODT, which is free and open source software available through the Apache Software Foundation, is particularly well suited to developing and managing arbitrary large-scale ETL processes both for the simplicity and flexibility of its wrapper framework, as well as the detailed provenance information it exposes throughout the process. Our experience using OODT to manage processing of large-scale data sets in domains as diverse as radio astronomy, life sciences, and social network analysis demonstrates the flexibility of the framework, and the range of potential applications to a broad array of big data ETL challenges.
NASA Astrophysics Data System (ADS)
Savina, Irina N.; Ingavle, Ganesh C.; Cundy, Andrew B.; Mikhalovsky, Sergey V.
2016-02-01
The development of bulk, three-dimensional (3D), macroporous polymers with high permeability, large surface area and large volume is highly desirable for a range of applications in the biomedical, biotechnological and environmental areas. The experimental techniques currently used are limited to the production of small size and volume cryogel material. In this work we propose a novel, versatile, simple and reproducible method for the synthesis of large volume porous polymer hydrogels by cryogelation. By controlling the freezing process of the reagent/polymer solution, large-scale 3D macroporous gels with wide interconnected pores (up to 200 μm in diameter) and large accessible surface area have been synthesized. For the first time, macroporous gels (of up to 400 ml bulk volume) with controlled porous structure were manufactured, with potential for scale up to much larger gel dimensions. This method can be used for production of novel 3D multi-component macroporous composite materials with a uniform distribution of embedded particles. The proposed method provides better control of freezing conditions and thus overcomes existing drawbacks limiting production of large gel-based devices and matrices. The proposed method could serve as a new design concept for functional 3D macroporous gels and composites preparation for biomedical, biotechnological and environmental applications.
Forecasting Demand for KC-135 Sorties: Deploy to Dwell Impacts
2013-06-01
fighter movements from individual units are rampant (6 OSS/ OSOS , 2013). However, TACC directed missions in this category are scarce, if not non...existent (6 OSS/ OSOS , 2013). Recent TACC tasked missions that appear to support CONUS fighter movements were training related: pre-deployment preparation...and large scale exercises directed by the Joint Staff (6 OSS/ OSOS , 2013). Anecdotal evidence that AMC supports CONUS fighter movements was flawed
ERIC Educational Resources Information Center
Schwille, John, Ed.; Ingvarson, Lawrence, Ed.; Holdgreve-Resendez, Richard, Ed.
2013-01-01
The IEA Teacher Education and Development Study in Mathematics (TEDS-M) is the first large-scale international study of the preparation of primary and lower-secondary teachers. The study investigated the pedagogical and subject-specific knowledge that future primary and lower secondary school teachers acquire during their mathematics teacher…
Hedging against terrorism: Are US businesses prepared?
Kahan, Jerome H
2015-01-01
Private US companies face risks in connection with financial matters, but are not necessarily prepared to cope with risks that can seriously disrupt or even halt their operations, notably terrorist attacks and natural disasters. Enhancing the resilience of businesses when dealing with terrorism is especially challenging, as these groups or individuals can adapt tactics to exploit the vulnerabilities of companies they wish to target. Business managers need to formulate flexible preparedness plans that reduce risks from large-scale natural disasters as well as terrorist attacks. In doing so, they can take advantage of post-9/11 US government guidance for these endeavours as well as programmes that eliminate risks to private insurance entities so they can issue policies that cover terrorist strikes of high consequences. Just as business executives use hedging strategies in the world of finance, they also need operational hedging strategies as a means of exploiting as well as lowering the risks surrounding future uncertainties. Resources devoted to planning and hedging are investments that can increase the odds of businesses surviving and thriving, even if they experience high-impact terrorist attacks, threats or large-scale natural disasters, making suppliers, customers and stakeholders happy. The purpose of this paper is to give executives the incentive to take steps to do just that.
NASA Astrophysics Data System (ADS)
Hamelin, Elizabeth I.; Blake, Thomas A.; Perez, Jonas W.; Crow, Brian S.; Shaner, Rebecca L.; Coleman, Rebecca M.; Johnson, Rudolph C.
2016-05-01
Public health response to large scale chemical emergencies presents logistical challenges for sample collection, transport, and analysis. Diagnostic methods used to identify and determine exposure to chemical warfare agents, toxins, and poisons traditionally involve blood collection by phlebotomists, cold transport of biomedical samples, and costly sample preparation techniques. Use of dried blood spots, which consist of dried blood on an FDA-approved substrate, can increase analyte stability, decrease infection hazard for those handling samples, greatly reduce the cost of shipping/storing samples by removing the need for refrigeration and cold chain transportation, and be self-prepared by potentially exposed individuals using a simple finger prick and blood spot compatible paper. Our laboratory has developed clinical assays to detect human exposures to nerve agents through the analysis of specific protein adducts and metabolites, for which a simple extraction from a dried blood spot is sufficient for removing matrix interferents and attaining sensitivities on par with traditional sampling methods. The use of dried blood spots can bridge the gap between the laboratory and the field allowing for large scale sample collection with minimal impact on hospital resources while maintaining sensitivity, specificity, traceability, and quality requirements for both clinical and forensic applications.
5 CFR 532.233 - Preparation for full-scale wage surveys.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Preparation for full-scale wage surveys... REGULATIONS PREVAILING RATE SYSTEMS Prevailing Rate Determinations § 532.233 Preparation for full-scale wage... the local wage survey committee. (e) Selection and appointment of data collectors. (1) The local wage...
Lelental, Natalia; Brandner, Sebastian; Kofanova, Olga; Blennow, Kaj; Zetterberg, Henrik; Andreasson, Ulf; Engelborghs, Sebastiaan; Mroczko, Barbara; Gabryelewicz, Tomasz; Teunissen, Charlotte; Mollenhauer, Brit; Parnetti, Lucilla; Chiasserini, Davide; Molinuevo, Jose Luis; Perret-Liaudet, Armand; Verbeek, Marcel M; Andreasen, Niels; Brosseron, Frederic; Bahl, Justyna M C; Herukka, Sanna-Kaisa; Hausner, Lucrezia; Frölich, Lutz; Labonte, Anne; Poirier, Judes; Miller, Anne-Marie; Zilka, Norbert; Kovacech, Branislav; Urbani, Andrea; Suardi, Silvia; Oliveira, Catarina; Baldeiras, Ines; Dubois, Bruno; Rot, Uros; Lehmann, Sylvain; Skinningsrud, Anders; Betsou, Fay; Wiltfang, Jens; Gkatzima, Olymbia; Winblad, Bengt; Buchfelder, Michael; Kornhuber, Johannes; Lewczuk, Piotr
2016-03-01
Assay-vendor independent quality control (QC) samples for neurochemical dementia diagnostics (NDD) biomarkers are so far commercially unavailable. This requires that NDD laboratories prepare their own QC samples, for example by pooling leftover cerebrospinal fluid (CSF) samples. To prepare and test alternative matrices for QC samples that could facilitate intra- and inter-laboratory QC of the NDD biomarkers. Three matrices were validated in this study: (A) human pooled CSF, (B) Aβ peptides spiked into human prediluted plasma, and (C) Aβ peptides spiked into solution of bovine serum albumin in phosphate-buffered saline. All matrices were tested also after supplementation with an antibacterial agent (sodium azide). We analyzed short- and long-term stability of the biomarkers with ELISA and chemiluminescence (Fujirebio Europe, MSD, IBL International), and performed an inter-laboratory variability study. NDD biomarkers turned out to be stable in almost all samples stored at the tested conditions for up to 14 days as well as in samples stored deep-frozen (at - 80°C) for up to one year. Sodium azide did not influence biomarker stability. Inter-center variability of the samples sent at room temperature (pooled CSF, freeze-dried CSF, and four artificial matrices) was comparable to the results obtained on deep-frozen samples in other large-scale projects. Our results suggest that it is possible to replace self-made, CSF-based QC samples with large-scale volumes of QC materials prepared with artificial peptides and matrices. This would greatly facilitate intra- and inter-laboratory QC schedules for NDD measurements.
Accelerating root system phenotyping of seedlings through a computer-assisted processing pipeline.
Dupuy, Lionel X; Wright, Gladys; Thompson, Jacqueline A; Taylor, Anna; Dekeyser, Sebastien; White, Christopher P; Thomas, William T B; Nightingale, Mark; Hammond, John P; Graham, Neil S; Thomas, Catherine L; Broadley, Martin R; White, Philip J
2017-01-01
There are numerous systems and techniques to measure the growth of plant roots. However, phenotyping large numbers of plant roots for breeding and genetic analyses remains challenging. One major difficulty is to achieve high throughput and resolution at a reasonable cost per plant sample. Here we describe a cost-effective root phenotyping pipeline, on which we perform time and accuracy benchmarking to identify bottlenecks in such pipelines and strategies for their acceleration. Our root phenotyping pipeline was assembled with custom software and low cost material and equipment. Results show that sample preparation and handling of samples during screening are the most time consuming task in root phenotyping. Algorithms can be used to speed up the extraction of root traits from image data, but when applied to large numbers of images, there is a trade-off between time of processing the data and errors contained in the database. Scaling-up root phenotyping to large numbers of genotypes will require not only automation of sample preparation and sample handling, but also efficient algorithms for error detection for more reliable replacement of manual interventions.
Fabrication of Electrophoretic Display Driven by Membrane Switch Array
NASA Astrophysics Data System (ADS)
Senda, Kazuo; Usui, Hiroaki
2010-04-01
Electrophoretic devices (EPDs) and organic light-emitting diodes (OLEDs) have potential application in a large-area flexible displays, such as digital signage. For this purpose, a new backplane is capable of driving a large unit is required instead of thin-film transistors. In this paper we describe the fabrication of a membrane switch array suitable for driving large-scale flat-panel displays. An array of membrane switches was prepared using flexible printed circuit (FPC) technology of polyimide films, by combining low-temperature processes of lamination and copper electroplating methods. An array of 256 matrix switches with a pixel size of 7 mm2 was prepared to drive the EPD front panel. The switches were driven at a voltage of about 40 V and a frequency of 10 Hz. The operation characteristics agreed well with the result of the theoretical calculation. The calculation also suggested that driving voltage can be lowered by increasing pixel size. The contact resistance of the membrane switch was as low as 0.2 Ω, which implies the wide applicability of this device for driving a variety of elements.
Chen, Mian; Yang, Lei; Zhang, Lan; Han, Yong; Lu, Zheng; Qin, Gaowu; Zhang, Erlin
2017-06-01
In this research, Ti-Ag alloys were prepared by powder metallurgy, casting and heat treatment method in order to investigate the effect of Ag compound particles on the bio-corrosion, the antibacterial property and the cell biocompatibility. Ti-Ag alloys with different sizes of Ag or Ag-compounds particles were successfully prepared: small amount of submicro-scale (100nm) Ti 2 Ag precipitates with solid solution state of Ag, large amount of nano-scale (20-30nm) Ti 2 Ag precipitates with small amount of solid solution state of Ag and micro-scale lamellar Ti 2 Ag phases, and complete solid solution state of Ag. The mechanical tests indicated that both nano/micro-scale Ti 2 Ag phases had a strong dispersion strengthening ability and Ag had a high solid solution strengthening ability. Electrochemical results shown the Ag content and the size of Ag particles had a limited influence on the bio-corrosion resistance although nano-scale Ti 2 Ag precipitates slightly improved corrosion resistance. It was demonstrated that the nano Ag compounds precipitates have a significant influence on the antibacterial properties of Ti-Ag alloys but no effect on the cell biocompatibility. It was thought that both Ag ions release and Ti 2 Ag precipitates contributed to the antibacterial ability, in which nano-scale and homogeneously distributed Ti 2 Ag phases would play a key role in antibacterial process. Copyright © 2017 Elsevier B.V. All rights reserved.
Sakai, Toshiro; Thommes, Markus
2014-02-01
The goal of this investigation was to qualify the DSM Xplore Pharma Micro Extruder as a formulation screening tool for early-stage hot-melt extrusion. Dispersive and distributive mixing was investigated using soluplus, copovidone or basic butylated methacrylate copolymer with sodium chloride (NaCl) in a batch size of 5 g. Eleven types of solid dispersions were prepared using various drugs and carriers in batches of 5 g in accordance with the literature. The dispersive mixing was a function of screw speed and recirculation time and the particle size was remarkably reduced after 1 min of processing, regardless of the polymers. An inverse relationship between the particle size and specific mechanical energy (SME) was also found. The SME values were higher than those in large-scale extruders. After 1 min recirculation at 200 rpm, the uniformity of NaCl content met the criteria of the European Pharmacopoeia, indicating that distributive mixing was achieved in this time. For the solid dispersions preparations, the results from different scanning calorimetry, powder X-ray diffractometry and in-vitro dissolution tests confirmed that all solid-dispersion systems were successfully prepared. These findings demonstrated that the extruder is a useful tool to screen solid-dispersion formulations and their material properties on a small scale. © 2013 Royal Pharmaceutical Society.
Metal molybdate nanorods as non-precious electrocatalysts for the oxygen reduction
NASA Astrophysics Data System (ADS)
Wu, Tian; Zhang, Lieyu
2015-12-01
Development of non-precious electrocatalysts with applicable electrocatalytic activity towards the oxygen reduction reaction (ORR) is important to fulfill broad-based and large-scale applications of metal/air batteries and fuel cells. Herein, nickel and cobalt molybdates with uniform nanorod morphology are synthesized using a facile one-pot hydrothermal method. The ORR activity of the prepared metal molybdate nanorods in alkaline media are investigated by using cyclic voltammetry (CV), linear sweep voltammetry (LSV) and chronoamperomety in rotating disk electrode (RDE) techniques. The present study suggests that the prepared metal molybdate nanorods exhibit applicable electrocatalytic activities towards the ORR in alkaline media, promising the applications as non-precious cathode in fuel cells and metal-air batteries.
Qiao, Zhen-An; Chai, Song-Hai; Nelson, Kimberly; Bi, Zhonghe; Chen, Jihua; Mahurin, Shannon M; Zhu, Xiang; Dai, Sheng
2014-04-16
High-performance polymeric membranes for gas separation are attractive for molecular-level separations in industrial-scale chemical, energy and environmental processes. Molecular sieving materials are widely regarded as the next-generation membranes to simultaneously achieve high permeability and selectivity. However, most polymeric molecular sieve membranes are based on a few solution-processable polymers such as polymers of intrinsic microporosity. Here we report an in situ cross-linking strategy for the preparation of polymeric molecular sieve membranes with hierarchical and tailorable porosity. These membranes demonstrate exceptional performance as molecular sieves with high gas permeabilities and selectivities for smaller gas molecules, such as carbon dioxide and oxygen, over larger molecules such as nitrogen. Hence, these membranes have potential for large-scale gas separations of commercial and environmental relevance. Moreover, this strategy could provide a possible alternative to 'classical' methods for the preparation of porous membranes and, in some cases, the only viable synthetic route towards certain membranes.
Zhou, Xiaofeng; Cai, Guoqiang; He, Yi; Tong, Guotong
2016-01-01
Cordycepin exhibits various bio-activities, including anticancer, antibacterial, antiviral and immune regulation activities, and is a significant focus of research. However, the preparation of high-purity cordycepin remains challenging. Also, the molecular target with which cordycepin interacts to cause an antibacterial effect remains unknown. In the present study, cordycepin was prepared by preparative high-performance liquid chromatography (prep-HPLC) and the purity obtained was 99.6%, indicating that this technique may be useful for the large-scale isolation of cordycepin in the future. The results of computational molecular docking analysis indicated that the interaction energy between cordycepin and NAD+-dependent DNA ligase (LigA) was lower than that between cordycepin and other common antibacterial targets. The highly pure cordycepin obtained by prep-HPLC demonstrated inhibitory activity against LigA from various bacteria in vitro. In conclusion, cordycepin may be useful as a broad-spectrum antibiotic targeting LigA in various bacteria. PMID:27588098
AAO-based nanoreservoir arrays: A quick and easy support for TEM characterization
NASA Astrophysics Data System (ADS)
Mace, M.; Sahaf, H.; Moyen, E.; Bedu, F.; Masson, L.; Hanbücken, M.
2010-12-01
Large-scale arrays of calibrated, nanometer sized reservoirs are prepared by adapting the well-established electrochemical method used so far for the preparation of anodic aluminium oxide (AAO) membranes. The bottom plane of the assembly is prepared to be transparent for high-energy electrons, enabling their use as a universal sample support for transmission electron microscopy studies of nanoparticles. The nanoreservoir substrates can be cleaned under ultra-high-vacuum conditions and filled, by evaporating different materials. Filled nanoreservoirs can locally be sealed with a thin carbon layer using focused-ion-beam-induced deposition (FIBID). Nanoparticles, grow at various adsorption places on the walls and bottom planes inside the nanoreservoirs. They can be characterized by transmission electron microscopy (TEM) without further sample preparation in different crystallographic directions. Due to the dense array-arrangement of the reservoirs, very good statistics can already be obtained on one single sample. The controlled fabrication of the nanoreservoir array and first TEM results obtained on Au nanoparticles before and after sealing of the reservoirs, are presented.
Preparative supercritical fluid chromatography: A powerful tool for chiral separations.
Speybrouck, David; Lipka, Emmanuelle
2016-10-07
In 2012, the 4 biggest pharmaceutical blockbusters were pure enantiomers and separating racemic mixtures is now frequently a key step in the development of a new drug. For a long time, preparative liquid chromatography was the technique of choice for the separation of chiral compounds either during the drug discovery process to get up to a hundred grams of a pure enantiomer or during the clinical trial phases needing kilograms of material. However the advent of supercritical Fluid Chromatography (SFC) in the 1990s has changed things. Indeed, the use of carbon dioxide as the mobile phase in SFC offers many advantages including high flow rate, short equilibration time as well as low solvent consumption. Despite some initial teething troubles, SFC is becoming the primary method for preparative chiral chromatography. This article will cover recent developments in preparative SFC for the separation of enantiomers, reviewing several aspects such as instrumentation, chiral stationary phases, mobile phases or purely preparative considerations including overloading, productivity or large scale chromatography. Copyright © 2016 Elsevier B.V. All rights reserved.
Green synthesis of carbon quantum dots from lignite coal and the application in Fe3+ detection
NASA Astrophysics Data System (ADS)
Liu, Xuexia; Hao, Juanyuan; Liu, Jianhui; Tao, Hongcai
2018-02-01
Carbon quantum dots (CQDs) had attracted much attention due to their unique structures and excellent properties. Their green preparation was one of the research frontiers. However, most of the CQDs were prepared by strong acid oxidation, the way of which was not friendly to the environment. In this study, CQDs were prepared by green ozone oxidation of lignite coal, which is abundant and inexpensive. The CQDs were well dispersed, the size distribution of the obtained CQDs centralized from 2 to 4 nm with the average diameter of about 2.8 nm. In addition, the as-prepared CQDs containing rich oxygen functional groups exhibited good water-solubility and optical properties with yield reached 35%. The CQDs showed a highly sensitive and selective quenching effect to Fe3+ with desirable anti-interference performance. Moreover, the fluorescence intensity of CQDs had a good linear response to the Fe3+ concentration ranging from 10 to 150 µmol/L with the detection limit of 0.26 µmol/L. This green and facile synthesis method had the prospect of large-scale preparation of CQDs.
Honda, Michitaka; Wakita, Takafumi; Onishi, Yoshihiro; Nunobe, Souya; Miura, Akinori; Nishigori, Tatsuto; Kusanagi, Hiroshi; Yamamoto, Takatsugu; Boddy, Alexander; Fukuhara, Shunichi
2015-12-01
Patients who have undergone esophagectomy or gastrectomy have certain dietary limitations because of changes to the alimentary tract. This study attempted to develop a psychometric scale, named "Esophago-Gastric surgery and Quality of Dietary life (EGQ-D)," for assessment of impact of upper gastrointestinal surgery on diet-targeted quality of life. Using qualitative methods, the study team interviewed both patients and surgeons involved in esophagogastric cancer surgery, and we prepared an item pool and a draft scale. To evaluate the scale's psychometric reliability and validity, a survey involving a large number of patients was conducted. Items for the final scale were selected by factor analysis and item response theory. Cronbach's alpha was used for assessment of reliability, and correlations with the short form (SF)-12, esophagus and stomach surgery symptom scale (ES(4)), and nutritional indicators were analyzed to assess the criterion-related validity. Through multifaceted discussion and the pilot study, a draft questionnaire comprising 14 items was prepared, and a total of 316 patients were enrolled. On the basis of factor analysis and item response theory, six items were excluded, and the remaining eight items demonstrated strong unidimensionality for the final scale. Cronbach's alpha was 0.895. There were significant associations with all the subscale scores for SF-12, ES(4), and nutritional indicators. The EGQ-D scale has good contents and psychometric validity and can be used to evaluate disease-specific instrument to measure diet-targeted quality of life for postoperative patients with esophagogastric cancer.
Uteng, Marianne; Hauge, Håvard Hildeng; Brondz, Ilia; Nissen-Meyer, Jon; Fimland, Gunnar
2002-01-01
A rapid and simple two-step procedure suitable for both small- and large-scale purification of pediocin-like bacteriocins and other cationic peptides has been developed. In the first step, the bacterial culture was applied directly on a cation-exchange column (1-ml cation exchanger per 100-ml cell culture). Bacteria and anionic compounds passed through the column, and cationic bacteriocins were subsequently eluted with 1 M NaCl. In the second step, the bacteriocin fraction was applied on a low-pressure, reverse-phase column and the bacteriocins were detected as major optical density peaks upon elution with propanol. More than 80% of the activity that was initially in the culture supernatant was recovered in both purification steps, and the final bacteriocin preparation was more than 90% pure as judged by analytical reverse-phase chromatography and capillary electrophoresis. PMID:11823243
Tools for phospho- and glycoproteomics of plasma membranes.
Wiśniewski, Jacek R
2011-07-01
Analysis of plasma membrane proteins and their posttranslational modifications is considered as important for identification of disease markers and targets for drug treatment. Due to their insolubility in water, studying of plasma membrane proteins using mass spectrometry has been difficult for a long time. Recent technological developments in sample preparation together with important improvements in mass spectrometric analysis have facilitated analysis of these proteins and their posttranslational modifications. Now, large scale proteomic analyses allow identification of thousands of membrane proteins from minute amounts of sample. Optimized protocols for affinity enrichment of phosphorylated and glycosylated peptides have set new dimensions in the depth of characterization of these posttranslational modifications of plasma membrane proteins. Here, I summarize recent advances in proteomic technology for the characterization of the cell surface proteins and their modifications. In the focus are approaches allowing large scale mapping rather than analytical methods suitable for studying individual proteins or non-complex mixtures.
Extremely Scalable Spiking Neuronal Network Simulation Code: From Laptops to Exascale Computers.
Jordan, Jakob; Ippen, Tammo; Helias, Moritz; Kitayama, Itaru; Sato, Mitsuhisa; Igarashi, Jun; Diesmann, Markus; Kunkel, Susanne
2018-01-01
State-of-the-art software tools for neuronal network simulations scale to the largest computing systems available today and enable investigations of large-scale networks of up to 10 % of the human cortex at a resolution of individual neurons and synapses. Due to an upper limit on the number of incoming connections of a single neuron, network connectivity becomes extremely sparse at this scale. To manage computational costs, simulation software ultimately targeting the brain scale needs to fully exploit this sparsity. Here we present a two-tier connection infrastructure and a framework for directed communication among compute nodes accounting for the sparsity of brain-scale networks. We demonstrate the feasibility of this approach by implementing the technology in the NEST simulation code and we investigate its performance in different scaling scenarios of typical network simulations. Our results show that the new data structures and communication scheme prepare the simulation kernel for post-petascale high-performance computing facilities without sacrificing performance in smaller systems.
Extremely Scalable Spiking Neuronal Network Simulation Code: From Laptops to Exascale Computers
Jordan, Jakob; Ippen, Tammo; Helias, Moritz; Kitayama, Itaru; Sato, Mitsuhisa; Igarashi, Jun; Diesmann, Markus; Kunkel, Susanne
2018-01-01
State-of-the-art software tools for neuronal network simulations scale to the largest computing systems available today and enable investigations of large-scale networks of up to 10 % of the human cortex at a resolution of individual neurons and synapses. Due to an upper limit on the number of incoming connections of a single neuron, network connectivity becomes extremely sparse at this scale. To manage computational costs, simulation software ultimately targeting the brain scale needs to fully exploit this sparsity. Here we present a two-tier connection infrastructure and a framework for directed communication among compute nodes accounting for the sparsity of brain-scale networks. We demonstrate the feasibility of this approach by implementing the technology in the NEST simulation code and we investigate its performance in different scaling scenarios of typical network simulations. Our results show that the new data structures and communication scheme prepare the simulation kernel for post-petascale high-performance computing facilities without sacrificing performance in smaller systems. PMID:29503613
Behavior of a Large-Scale Pile Group Subjected to Cyclic Lateral Loading.
1988-02-01
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Transition to organized behavior on suspensions of concentrated bacteria
NASA Astrophysics Data System (ADS)
Ganguly, Sujoy; Cisneros, Luis; Kessler, John; Goldstein, Raymond
2008-11-01
Concentrated populations of the swimming bacterium Bacillus subtilis develop a collective phase, the Zooming BioNematic, that exhibits large-scale coherence analogous to the molecular alignment of nematic liquid crystals. Bacterial suspensions were prepared in order to experimentally measure the transition to organized behavior as a function of the cell number concentration. PIV analysis was used to obtain cell velocities and define an order parameter in order to characterize the dynamics of the system.
Chen, Feng; Zhu, Ying-Jie
2016-12-27
Practical applications of nanostructured materials have been largely limited by the difficulties in controllable and scaled-up synthesis, large-sized highly ordered self-assembly, and macroscopic processing of nanostructures. Hydroxyapatite (HAP), the major inorganic component of human bone and tooth, is an important biomaterial with high biocompatibility, bioactivity, and high thermal stability. Large-sized highly ordered HAP nanostructures are of great significance for applications in various fields and for understanding the formation mechanisms of bone and tooth. However, the synthesis of large-sized highly ordered HAP nanostructures remains a great challenge, especially for the preparation of large-sized highly ordered ultralong HAP nanowires because ultralong HAP nanowires are easily tangled and aggregated. Herein, we report our three main research findings: (1) the large-scale synthesis of highly flexible ultralong HAP nanowires with lengths up to >100 μm and aspect ratios up to >10000; (2) the demonstration of a strategy for the rapid automated production of highly flexible, fire-resistant, large-sized, self-assembled highly ordered ultralong HAP nanowires (SHOUHNs) at room temperature; and (3) the successful construction of various flexible fire-resistant HAP ordered architectures using the SHOUHNs, such as high-strength highly flexible nanostructured ropes (nanoropes), highly flexible textiles, and 3-D printed well-defined highly ordered patterns. The SHOUHNs are successively formed from the nanoscale to the microscale then to the macroscale, and the ordering direction of the ordered HAP structure is controllable. These ordered HAP architectures made from the SHOUHNs, such as highly flexible textiles, may be engineered into advanced functional products for applications in various fields, for example, fireproof clothing.
Carbon Microfibers with Hierarchical Porous Structure from Electrospun Fiber-Like Natural Biopolymer
NASA Astrophysics Data System (ADS)
Liang, Yeru; Wu, Dingcai; Fu, Ruowen
2013-01-01
Electrospinning offers a powerful route for building one-dimensional (1D) micro/nanostructures, but a common requirement for toxic or corrosive organic solvents during the preparation of precursor solution has limited their large scale synthesis and broad applications. Here we report a facile and low-cost way to prepare 1D porous carbon microfibers by using an electrospun fiber-like natural product, i.e., silk cocoon, as precursor. We surprisingly found that by utilizing a simple carbonization treatment, the cocoon microfiber can be directly transformed into 1D carbon microfiber of ca. 6 μm diameter with a unique three-dimensional porous network structure composed of interconnected carbon nanoparticles of 10~40 nm diameter. We further showed that the as-prepared carbon product presents superior electrochemical performance as binder-free electrodes of supercapacitors and good adsorption property toward organic vapor.
Reliable quantum certification of photonic state preparations
Aolita, Leandro; Gogolin, Christian; Kliesch, Martin; Eisert, Jens
2015-01-01
Quantum technologies promise a variety of exciting applications. Even though impressive progress has been achieved recently, a major bottleneck currently is the lack of practical certification techniques. The challenge consists of ensuring that classically intractable quantum devices perform as expected. Here we present an experimentally friendly and reliable certification tool for photonic quantum technologies: an efficient certification test for experimental preparations of multimode pure Gaussian states, pure non-Gaussian states generated by linear-optical circuits with Fock-basis states of constant boson number as inputs, and pure states generated from the latter class by post-selecting with Fock-basis measurements on ancillary modes. Only classical computing capabilities and homodyne or hetorodyne detection are required. Minimal assumptions are made on the noise or experimental capabilities of the preparation. The method constitutes a step forward in many-body quantum certification, which is ultimately about testing quantum mechanics at large scales. PMID:26577800
Boron-rich benzene and pyrene derivatives for the detection of thermal neutrons
Yemam, Henok A.; Mahl, Adam; Koldemir, Unsal; Remedes, Tyler; Parkin, Sean; Greife, Uwe; Sellinger, Alan
2015-01-01
A synthetic methodology is developed to generate boron rich aromatic small molecules based on benzene and pyrene moieties for the detection of thermal neutrons. The prepared aromatic compounds have a relatively high boron content up to 7.4 wt%, which is important for application in neutron detection as 10B (20% of natural abundance boron) has a large neutron induced reaction cross-section. This is demonstrated by preparing blends of the synthesized molecules with fluorescent dopants in poly(vinyltoluene) matrices resulting in comparable scintillation light output and neutron capture as state-of-the art commercial scintillators, but with the advantage of much lower cost. The boron-rich benzene and pyrene derivatives are prepared by Suzuki conditions using both microwave and traditional heating, affording yields of 40–93%. This new procedure is simple and straightforward, and has the potential to be scaled up. PMID:26334111
NASA Astrophysics Data System (ADS)
Ma, Zhijun; Ji, Huijiao; Tan, Dezhi; Dong, Guoping; Teng, Yu; Zhou, Jiajia; Guan, Miaojia; Qiu, Jianrong; Zhang, Ming
2011-07-01
In this paper, we report on a novel strategy for the preparation of silver nanoparticle-doped SiO2 microspheres (Ag-SMSs) with an interesting strawberry-like morphology using a simple and efficient electrospraying method. SEM (scanning electron microscopy), TEM (transmission electron microscopy), XRD (x-ray diffraction), EDS (energy-dispersive spectroscopy) and UV-vis spectra (ultraviolet-visible spectra) were applied to investigate the morphology, structure, composition and optical properties of the hybrid microspheres, and E. coli (Escherichia coli) was used as a model microbe to evaluate their antibacterial ability. The results showed that the Ag-SMSs were environmentally stable and washing resistant. The Ag-SMSs exhibited effective inhibition against proliferation of E. coli, and their antibacterial ability could be well preserved for a long time. The environmental stability, washing resistance, efficient antibacterial ability and simple but productive preparation method endowed the Ag-SMSs with great potential for practical biomedical applications.
Hu, Chuangang; Xiao, Ying; Zhao, Yang; Chen, Nan; Zhang, Zhipan; Cao, Minhua; Qu, Liangti
2013-04-07
Highly nitrogen-doped carbon capsules (hN-CCs) have been successfully prepared by using inexpensive melamine and glyoxal as precursors via solvothermal reaction and carbonization. With a great promise for large scale production, the hN-CCs, having large surface area and high-level nitrogen content (N/C atomic ration of ca. 13%), possess superior crossover resistance, selective activity and catalytic stability towards oxygen reduction reaction for fuel cells in alkaline medium. As a new anode material in lithium-ion battery, hN-CCs also exhibit excellent cycle performance and high rate capacity with a reversible capacity of as high as 1046 mA h g(-1) at a current density of 50 mA g(-1) after 50 cycles. These features make the hN-CCs developed in this study promising as suitable substitutes for the expensive noble metal catalysts in the next generation alkaline fuel cells, and as advanced electrode materials in lithium-ion batteries.
Fabrication of Large-area Free-standing Ultrathin Polymer Films
Stadermann, Michael; Baxamusa, Salmaan H.; Aracne-Ruddle, Chantel; Chea, Maverick; Li, Shuaili; Youngblood, Kelly; Suratwala, Tayyab
2015-01-01
This procedure describes a method for the fabrication of large-area and ultrathin free-standing polymer films. Typically, ultrathin films are prepared using either sacrificial layers, which may damage the film or affect its mechanical properties, or they are made on freshly cleaved mica, a substrate that is difficult to scale. Further, the size of ultrathin film is typically limited to a few square millimeters. In this method, we modify a surface with a polyelectrolyte that alters the strength of adhesion between polymer and deposition substrate. The polyelectrolyte can be shown to remain on the wafer using spectroscopy, and a treated wafer can be used to produce multiple films, indicating that at best minimal amounts of the polyelectrolyte are added to the film. The process has thus far been shown to be limited in scalability only by the size of the coating equipment, and is expected to be readily scalable to industrial processes. In this study, the protocol for making the solutions, preparing the deposition surface, and producing the films is described. PMID:26066738
Yu, Chuang; Ganapathy, Swapna; Eck, Ernst R H van; Wang, Heng; Basak, Shibabrata; Li, Zhaolong; Wagemaker, Marnix
2017-10-20
Solid-state batteries potentially offer increased lithium-ion battery energy density and safety as required for large-scale production of electrical vehicles. One of the key challenges toward high-performance solid-state batteries is the large impedance posed by the electrode-electrolyte interface. However, direct assessment of the lithium-ion transport across realistic electrode-electrolyte interfaces is tedious. Here we report two-dimensional lithium-ion exchange NMR accessing the spontaneous lithium-ion transport, providing insight on the influence of electrode preparation and battery cycling on the lithium-ion transport over the interface between an argyrodite solid-electrolyte and a sulfide electrode. Interfacial conductivity is shown to depend strongly on the preparation method and demonstrated to drop dramatically after a few electrochemical (dis)charge cycles due to both losses in interfacial contact and increased diffusional barriers. The reported exchange NMR facilitates non-invasive and selective measurement of lithium-ion interfacial transport, providing insight that can guide the electrolyte-electrode interface design for future all-solid-state batteries.
Savina, Irina N.; Ingavle, Ganesh C.; Cundy, Andrew B.; Mikhalovsky, Sergey V.
2016-01-01
The development of bulk, three-dimensional (3D), macroporous polymers with high permeability, large surface area and large volume is highly desirable for a range of applications in the biomedical, biotechnological and environmental areas. The experimental techniques currently used are limited to the production of small size and volume cryogel material. In this work we propose a novel, versatile, simple and reproducible method for the synthesis of large volume porous polymer hydrogels by cryogelation. By controlling the freezing process of the reagent/polymer solution, large-scale 3D macroporous gels with wide interconnected pores (up to 200 μm in diameter) and large accessible surface area have been synthesized. For the first time, macroporous gels (of up to 400 ml bulk volume) with controlled porous structure were manufactured, with potential for scale up to much larger gel dimensions. This method can be used for production of novel 3D multi-component macroporous composite materials with a uniform distribution of embedded particles. The proposed method provides better control of freezing conditions and thus overcomes existing drawbacks limiting production of large gel-based devices and matrices. The proposed method could serve as a new design concept for functional 3D macroporous gels and composites preparation for biomedical, biotechnological and environmental applications. PMID:26883390
High- and low-throughput scoring of fat mass and body fat distribution in C. elegans
Wählby, Carolina; Lee-Conery, Annie; Bray, Mark-Anthony; Kamentsky, Lee; Larkins-Ford, Jonah; Sokolnicki, Katherine L.; Veneskey, Matthew; Michaels, Kerry; Carpenter, Anne E.; O’Rourke, Eyleen J.
2014-01-01
Fat accumulation is a complex phenotype affected by factors such as neuroendocrine signaling, feeding, activity, and reproductive output. Accordingly, the most informative screens for genes and compounds affecting fat accumulation would be those carried out in whole living animals. Caenorhabditis elegans is a well-established and effective model organism, especially for biological processes that involve organ systems and multicellular interactions, such as metabolism. Every cell in the transparent body of C. elegans is visible under a light microscope. Consequently, an accessible and reliable method to visualize worm lipid-droplet fat depots would make C. elegans the only metazoan in which genes affecting not only fat mass but also body fat distribution could be assessed at a genome-wide scale. Here we present a radical improvement in oil red O worm staining together with high-throughput image-based phenotyping. The three-step sample preparation method is robust, formaldehyde-free, and inexpensive, and requires only 15 minutes of hands-on time to process a 96-well plate. Together with our free and user-friendly automated image analysis package, this method enables C. elegans sample preparation and phenotype scoring at a scale that is compatible with genome-wide screens. Thus we present a feasible approach to small-scale phenotyping and large-scale screening for genetic and/or chemical perturbations that lead to alterations in fat quantity and distribution in whole animals. PMID:24784529
Snow Tweets: Emergency Information Dissemination in a US County During 2014 Winter Storms
Bonnan-White, Jess; Shulman, Jason; Bielecke, Abigail
2014-01-01
Introduction: This paper describes how American federal, state, and local organizations created, sourced, and disseminated emergency information via social media in preparation for several winter storms in one county in the state of New Jersey (USA). Methods: Postings submitted to Twitter for three winter storm periods were collected from selected organizations, along with a purposeful sample of select private local users. Storm-related posts were analyzed for stylistic features (hashtags, retweet mentions, embedded URLs). Sharing and re-tweeting patterns were also mapped using NodeXL. Results: Results indicate emergency management entities were active in providing preparedness and response information during the selected winter weather events. A large number of posts, however, did not include unique Twitter features that maximize dissemination and discovery by users. Visual representations of interactions illustrate opportunities for developing stronger relationships among agencies. Discussion: Whereas previous research predominantly focuses on large-scale national or international disaster contexts, the current study instead provides needed analysis in a small-scale context. With practice during localized events like extreme weather, effective information dissemination in large events can be enhanced. PMID:25685629
Snow Tweets: Emergency Information Dissemination in a US County During 2014 Winter Storms.
Bonnan-White, Jess; Shulman, Jason; Bielecke, Abigail
2014-12-22
This paper describes how American federal, state, and local organizations created, sourced, and disseminated emergency information via social media in preparation for several winter storms in one county in the state of New Jersey (USA). Postings submitted to Twitter for three winter storm periods were collected from selected organizations, along with a purposeful sample of select private local users. Storm-related posts were analyzed for stylistic features (hashtags, retweet mentions, embedded URLs). Sharing and re-tweeting patterns were also mapped using NodeXL. RESULTS indicate emergency management entities were active in providing preparedness and response information during the selected winter weather events. A large number of posts, however, did not include unique Twitter features that maximize dissemination and discovery by users. Visual representations of interactions illustrate opportunities for developing stronger relationships among agencies. Whereas previous research predominantly focuses on large-scale national or international disaster contexts, the current study instead provides needed analysis in a small-scale context. With practice during localized events like extreme weather, effective information dissemination in large events can be enhanced.
NASA Astrophysics Data System (ADS)
Long, Marianna M.; Bishop, John Bradford; Delucas, Lawrence J.; Nagabhushan, Tattanhalli L.; Reichert, Paul; Smith, G. David
1997-01-01
The Protein Crystal Growth Facility (PCF) is space-flight hardware that accommodates large scale protein crystal growth experiments using temperature change as the inductive step. Recent modifications include specialized instrumentation for monitoring crystal nucleation with laser light scattering. This paper reviews results from its first seven flights on the Space Shuttle, the last with laser light scattering instrumentation in place. The PCF's objective is twofold: (1) the production of high quality protein crystals for x-ray analysis and subsequent structure-based drug design and (2) preparation of a large quantity of relatively contaminant free crystals for use as time-release protein pharmaceuticals. The first three Shuttle flights with bovine insulin constituted the PCF's proof of concept, demonstrating that the space-grown crystals were larger and diffracted to higher resolution than their earth-grown counterparts. The later four PCF missions were used to grow recombinant human insulin crystals for x-ray analysis and continue productions trials aimed at the development of a processing facility for crystalline recombinant a-interferon.
NDE application of ultrasonic tomography to a full-scale concrete structure.
Choi, Hajin; Popovics, John S
2015-06-01
Newly developed ultrasonic imaging technology for large concrete elements, based on tomographic reconstruction, is presented. The developed 3-D internal images (velocity tomograms) are used to detect internal defects (polystyrene foam and pre-cracked concrete prisms) that represent structural damage within a large steel reinforced concrete element. A hybrid air-coupled/contact transducer system is deployed. Electrostatic air-coupled transducers are used to generate ultrasonic energy and contact accelerometers are attached on the opposing side of the concrete element to detect the ultrasonic pulses. The developed hybrid testing setup enables collection of a large amount of high-quality, through-thickness ultrasonic data without surface preparation to the concrete. The algebraic reconstruction technique is used to reconstruct p-wave velocity tomograms from the obtained time signal data. A comparison with a one-sided ultrasonic imaging method is presented for the same specimen. Through-thickness tomography shows some benefit over one-sided imaging for highly reinforced concrete elements. The results demonstrate that the proposed through-thickness ultrasonic technique shows great potential for evaluation of full-scale concrete structures in the field.
Preservation of large-scale chromatin structure in FISH experiments
Hepperger, Claudia; Otten, Simone; von Hase, Johann
2006-01-01
The nuclear organization of specific endogenous chromatin regions can be investigated only by fluorescence in situ hybridization (FISH). One of the two fixation procedures is typically applied: (1) buffered formaldehyde or (2) hypotonic shock with methanol acetic acid fixation followed by dropping of nuclei on glass slides and air drying. In this study, we compared the effects of these two procedures and some variations on nuclear morphology and on FISH signals. We analyzed mouse erythroleukemia and mouse embryonic stem cells because their clusters of subcentromeric heterochromatin provide an easy means to assess preservation of chromatin. Qualitative and quantitative analyses revealed that formaldehyde fixation provided good preservation of large-scale chromatin structures, while classical methanol acetic acid fixation after hypotonic treatment severely impaired nuclear shape and led to disruption of chromosome territories, heterochromatin structures, and large transgene arrays. Our data show that such preparations do not faithfully reflect in vivo nuclear architecture. Electronic supplementary material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00412-006-0084-2 and is accessible for authorized users. PMID:17119992
Heavy hydrocarbon main injector technology
NASA Technical Reports Server (NTRS)
Fisher, S. C.; Arbit, H. A.
1988-01-01
One of the key components of the Advanced Launch System (ALS) is a large liquid rocket, booster engine. To keep the overall vehicle size and cost down, this engine will probably use liquid oxygen (LOX) and a heavy hydrocarbon, such as RP-1, as propellants and operate at relatively high chamber pressures to increase overall performance. A technology program (Heavy Hydrocarbon Main Injector Technology) is being studied. The main objective of this effort is to develop a logic plan and supporting experimental data base to reduce the risk of developing a large scale (approximately 750,000 lb thrust), high performance main injector system. The overall approach and program plan, from initial analyses to large scale, two dimensional combustor design and test, and the current status of the program are discussed. Progress includes performance and stability analyses, cold flow tests of injector model, design and fabrication of subscale injectors and calorimeter combustors for performance, heat transfer, and dynamic stability tests, and preparation of hot fire test plans. Related, current, high pressure, LOX/RP-1 injector technology efforts are also briefly discussed.
Yan, Kai; Wu, Di; Peng, Hailin; Jin, Li; Fu, Qiang; Bao, Xinhe; Liu, Zhongfan
2012-01-01
Device applications of graphene such as ultrafast transistors and photodetectors benefit from the combination of both high-quality p- and n-doped components prepared in a large-scale manner with spatial control and seamless connection. Here we develop a well-controlled chemical vapour deposition process for direct growth of mosaic graphene. Mosaic graphene is produced in large-area monolayers with spatially modulated, stable and uniform doping, and shows considerably high room temperature carrier mobility of ~5,000 cm2 V−1 s−1 in intrinsic portion and ~2,500 cm2 V−1 s−1 in nitrogen-doped portion. The unchanged crystalline registry during modulation doping indicates the single-crystalline nature of p–n junctions. Efficient hot carrier-assisted photocurrent was generated by laser excitation at the junction under ambient conditions. This study provides a facile avenue for large-scale synthesis of single-crystalline graphene p–n junctions, allowing for batch fabrication and integration of high-efficiency optoelectronic and electronic devices within the atomically thin film. PMID:23232410
Laboratory and Field Evaluation of Rapid Setting Cementitious Materials for Large Crater Repair
2010-05-01
frame used within which to complete the repair was the current NATO standard of 4 hr. A total of 6 simulated craters were prepared, with each repair...Combat Command 129 Andrews Street Langley Air Force Base, VA 23665 ERDC TR-10-4 ii Abstract: Current practice for expedient runway repair...penalty. Numerous commercial products are available. A full-scale field test was conducted using rapid setting materials to repair simulated bomb craters
Ceramic-metal composites prepared via tape casting and melt infiltration methods
NASA Astrophysics Data System (ADS)
Kim, Hyun Jun
Melt infiltration of preforms prepared by tape casting and lamination has been accomplished using a short-time infiltration process that significantly suppresses reaction product formation. For layered materials produced via infiltration of laminated ceramic tapes, of particular interest is the effect that a large change in microstructure has on infiltration, phase formation, and mechanical properties. Hardness of the fine scale composite layers is approximately three times higher than coarse scale layers, due to greater strength of the fine B4C network. Fractography showed that crack propagation occurred by brittle fracture of the carbide and ductile extension of the metal. Despite large differences in hardness, the fracture mode of the fine and coarse scale microstructures appears identical. Fluid flow modeling for tape casting was conducted with a Newtonian slurry under a parallel blade, and the effect of beveling the blade based on a one dimensional flow model is shown. The discussion on slurry deformation after the blade exit suggests that the mode of slurry deformation depends on the relative importance of the pressure gradient and wall shear and that the existence of zero shear plane might have a negative effect on particle alignment in the tape. The analysis of the flow under a beveled blade predicts that this configuration is more advantageous than the parallel blade for productivity and parallel blade is better for producing uniform particle alignment and thinner tape. Also, the one dimensional flow model for the beveled blade is shown to be a valid approximation of the fluid behavior below a blade angle of 45 degrees. The flow visualization study on tape casting was conducted with a transparent apparatus and model slurry. Most investigators have concluded that the shear stress between the doctor blade and moving carrier causes the particle alignment, but, according to the result of visualization experiment, some degree of particle alignment is already established in the reservoir. The fluid flow concept of tape casting is incorporated with a metal infiltration technique to prepare the ceramic-metal composites with tailored porosity and pore orientation. Boron carbide-aluminum system was used to prepare the composites, and its stiffness constants were investigated. The aligned metal ligaments rarely affect the stiffness constant anisotropy which appears to be caused by tape casting operation.
Salunkhe, Rahul R; Hsu, Shao-Hui; Wu, Kevin C W; Yamauchi, Yusuke
2014-06-01
We report an effective route for the preparation of layered reduced graphene oxide (rGO) with uniformly coated polyaniline (PANI) layers. These nanocomposites are synthesized by chemical oxidative polymerization of aniline monomer in the presence of layered rGO. SEM, TEM, X-ray photoelectron spectroscopy (XPS), FTIR, and Raman spectroscopy analysis results demonstrated that reduced graphene oxide-polyaniline (rGO-PANI) nanocomposites are successfully synthesized. Because of synergistic effects, rGO-PANI nanocomposites prepared by this approach exhibit excellent capacitive performance with a high specific capacitance of 286 F g(-1) and high cycle reversibility of 94 % after 2000 cycles. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
dos Santos, Antonio Rodolfo; Kunz, Ulrich; Turek, Thomas
2011-01-01
Summary In this contribution we present for the first time a continuous process for the production of highly active Pt catalysts supported by carbon nanotubes by use of an electrically heated tubular reactor. The synthesized catalysts show a high degree of dispersion and narrow distributions of cluster sizes. In comparison to catalysts synthesized by the conventional oil-bath method a significantly higher electrocatalytic activity was reached, which can be attributed to the higher metal loading and smaller and more uniformly distributed Pt particles on the carbon support. Our approach introduces a simple, time-saving and cost-efficient method for fuel cell catalyst preparation in a flow reactor which could be used at a large scale. PMID:22043252
NASA Technical Reports Server (NTRS)
Anderson, K. A.
1974-01-01
Papers are presented which were published as a result of a project involving the preparation of a topographical elevation contour map of Mars from all data sources available through 1969, as well as the observation of Mars by spectroscopic methods in 1971 to provide additional pressure data for topographic information. Topics of the papers include: the analysis of large-scale Martian topography variations - data preparation from earth based radar, earth based CO2 spectroscopy, and Mariners 6 and 7 CO2 spectroscopy; the analysis of water content in observed Martian white clouds; and Martian, lunar, and terrestrial crusts - a three-dimensional exercise in comparative geophysics.
NASA Astrophysics Data System (ADS)
Yue, Lu; Ge, Jingjing; Luo, Gaixia; Bian, Kaiting; Yin, Chao; Guan, Rongfeng; Zhang, Wenhui; Zhou, Zheng; Wang, Kaixin; Guo, Xiufeng
2018-03-01
A facile approach to prepare porous SnO2 and SnO2/C composite with Cu-Sn alloy as raw material by wet chemical reaction strategy has been developed. The prepared porous SnO2 and its carbon composite showed homogeneous mesoporous structure and high surface area, displayed superior rate performance and high reversible capacity of 625 mAh g-1 and 1185 mAh g-1 over 800 cycles at 0.4 A g-1, respectively. Compared with commercial SnO2, porous SnO2 sensor presented higher response, faster response/recovery capability, good selectivity and repeatability to ethanol at 180°C.
Optimal approach to quantum communication using dynamic programming.
Jiang, Liang; Taylor, Jacob M; Khaneja, Navin; Lukin, Mikhail D
2007-10-30
Reliable preparation of entanglement between distant systems is an outstanding problem in quantum information science and quantum communication. In practice, this has to be accomplished by noisy channels (such as optical fibers) that generally result in exponential attenuation of quantum signals at large distances. A special class of quantum error correction protocols, quantum repeater protocols, can be used to overcome such losses. In this work, we introduce a method for systematically optimizing existing protocols and developing more efficient protocols. Our approach makes use of a dynamic programming-based searching algorithm, the complexity of which scales only polynomially with the communication distance, letting us efficiently determine near-optimal solutions. We find significant improvements in both the speed and the final-state fidelity for preparing long-distance entangled states.
Facile fabrication of plate-shaped hydrohausmannite as electrode material for supercapacitors
NASA Astrophysics Data System (ADS)
Liang, Jun; Chai, Yao; Li, Deli; Li, Meng; Lu, Jiaxue; Li, Li; Luo, Min
2017-08-01
A simple and one-step solvothermal synthesis method has been developed to prepare two-dimensional (2-D) hydrohausmannite ((Mn4-2xMnx)Mn8O16-x(OH)x) nanoplates with radial length of 300 nm and thickness of about 25 nm in a binary ethanediamine/water solvent system. The formation mechanism of hydrohausmannite is suggested. As an anode material for electrochemical capacitors, the plate-shaped hydrohausmannite not only displays a high specific capacity (215 at 0.1 A g-1) and good rate capability, but also shows good stable performance along with 94% specific capacity retained after 3000 cycle tests. The method can be easily controlled and expected to be applicable for the large-scale preparation of the 2-D hydrohausmannite.
Sebaaly, Carine; Charcosset, Catherine; Stainmesse, Serge; Fessi, Hatem; Greige-Gerges, Hélène
2016-03-15
This work is dedicated to prepare liposomal dry powder formulations of inclusion complexes of clove essential oil (CEO) and its main component eugenol (Eug). Ethanol injection method and membrane contactor were applied to prepare liposomes at laboratory and large scale, respectively. Various liposomal formulations were tested: (1) free hydroxypropyl-β-cyclodextrin loaded liposomes; (2) drug in hydroxypropyl-β-cyclodextrin in liposomes (DCL); (3) DCL2 obtained by double loading technique, where the drug is added in the organic phase and the inclusion complex in the aqueous phase. Liposomes were characterized for their particle size, polydispersity index, Zeta potential, morphology, encapsulation efficiency of CEO components and Eug loading rate. Reproducible results were obtained with both injection devices. Compared to Eug-loaded liposomes, DCL and DCL2 improved the loading rate of Eug and possessed smaller vesicles size. The DPPH(•) scavenging activity of Eug and CEO was maintained upon incorporation of Eug and CEO into DCL and DCL2. Contrary to DCL2, DCL formulations were stable after 1 month of storage at 4°C and upon reconstitution of the dried lyophilized cakes. Hence, DCL in aqueous and lyophilized forms, are considered as a promising carrier system to preserve volatile and hydrophobic drugs enlarging their application in cosmetic, pharmaceutical and food industries. Copyright © 2015 Elsevier Ltd. All rights reserved.
Ponce, David A.; Mankinen, E.A.; Davidson, J.G.; Morin, R.L.; Blakely, R.J.
2000-01-01
An isostatic gravity map of the Nevada Test Site area was prepared from publicly available gravity data (Ponce, 1997) and from gravity data recently collected by the U.S. Geological Survey (Mankinen and others, 1999; Morin and Blakely, 1999). Gravity data were processed using standard gravity data reduction techniques. Southwest Nevada is characterized by gravity anomalies that reflect the distribution of pre-Cenozoic carbonate rocks, thick sequences of volcanic rocks, and thick alluvial basins. In addition, regional gravity data reveal the presence of linear features that reflect large-scale faults whereas detailed gravity data can indicate the presence of smaller-scale faults.
Catalysis on Single Supported Atoms
DOE Office of Scientific and Technical Information (OSTI.GOV)
DeBusk, Melanie Moses; Narula, Chaitanya Kumar
2015-01-01
The highly successful application of supported metals as heterogeneous catalysts in automotive catalysts, fuel cells, and other multitudes of industrial processes have led to extensive efforts to understand catalyst behavior at the nano-scale. Recent discovery of simple wet methods to prepare single supported atoms, the smallest nano-catalyst, has allowed for experimental validation of catalytic activity of a variety of catalysts and potential for large scale production for such catalysts for industrial processes. In this chapter, we summarize the synthetic and structural aspects of single supported atoms. We also present proposed mechanisms for the activity of single supported catalysts where conventionalmore » mechanisms cannot operate due to lack of M-M bonds in the catalysts.« less
Brief scale measuring patient preparedness for hospital discharge to home: Psychometric properties.
Graumlich, James F; Novotny, Nancy L; Aldag, Jean C
2008-01-01
Adverse events occur when patients transition from the hospital to outpatient care. For quality improvement and research purposes, clinicians need appropriate, reliable, and valid survey instruments to measure and improve the discharge processes. The object was to describe psychometric properties of the Brief PREPARED (B-PREPARED) instrument to measure preparedness for hospital discharge from the patient's perspective. The study was a prospective cohort of 460 patient or proxy telephone interviews following hospital discharge home. We administered the Satisfaction with Information about Medicines Scale and the PREPARED instrument 1 week after discharge. PREPARED measured patients' perceptions of quality and outcome of the discharge-planning processes. Four weeks after discharge, interviewers elicited emergency department visits. The main outcome was the B-PREPARED scale value: the sum of scores from 11 items. Internal consistency, construct, and predictive validity were assessed. : The mean B-PREPARED scale value was 17.3 +/- 4.2 (SD) with a range of 3 to 22. High scores reflected high preparedness. Principal component analysis identified 3 domains: self-care information, equipment/services, and confidence. The B-PREPARED had acceptable internal consistency (Cronbach's alpha 0.76) and construct validity. The B-PREPARED correlated with medication information satisfaction (P < 0.001). Higher median B-PREPARED scores appropriately discriminated patients with no worry about managing at home from worriers (P < 0.001) and predicted patients without emergency department visits after discharge from those who had visits (P = 0.011). The B-PREPARED scale measured patients' perceptions of their preparedness for hospital discharge home with acceptable internal consistency and construct and predictive validity. Brevity may potentiate use by patients and proxies. Clinicians and researchers may use B-PREPARED to evaluate discharge interventions. (c) 2008 Society of Hospital Medicine.
Polyethylene glycol powder solution versus senna for bowel preparation for colonoscopy in children.
Terry, Natalie A; Chen-Lim, Mei Lin; Ely, Elizabeth; Jatla, Muralidhar; Ciavardone, Denise; Esch, Salina; Farace, Lisa; Jannelli, Frances; Puma, Anita; Carlow, Dean; Mamula, Petar
2013-02-01
Safety and effectiveness of large-volume polyethylene glycol-based solution (PEG-ES) have been documented, but the taste and volume can be barriers to successful colonoscopy preparation. Efficacy and safety of small-volume electrolyte-free (PEG-P) preparation (Miralax) for colonoscopy preparation have been rarely studied, although presently used at many pediatric centers. The primary objective of the present study was to determine whether PEG-P results in a more efficacious and safe colonoscopy preparation as compared with senna. The study design was prospective, randomized, and single-blinded. Patients ages 6 to 21 years were randomized to a 2-day clean-out regimen of PEG-P at a dose of 1.5 g/kg divided twice per day for 2 days versus senna 15 mL daily (ages 6-12) or 30 mL daily (ages 12-21) for 2 days. Both preparations required 1 day of clear liquids whereas senna preparation required an additional day of full liquid diet. A blinded endoscopist graded the quality of preparation with a standardized cleanliness tool (Aronchick scale). Serum chemistry panels were obtained. Patients or parents rated symptoms and ease of preparation. The anticipated number of subjects was 166; however, the interim analysis demonstrated inferiority of senna preparation. Thirty patients were evaluated in the present study. Of the patients in the PEG-P arm, 88% (14/16) received an excellent/good score compared with 29% (4/14), with the senna preparation (P = 0.0022). Both preparations were well-tolerated by patient-graded ease of preparation. Demographics and laboratory values did not differ significantly across the 2 groups. No serious adverse events were noted. PEG-P is an effective colonoscopy preparation whereas senna preparation was insufficient. Both were well-tolerated and appear safe in a pediatric population.
Liu, Wei; Yang, Xiang-Liang; Ho, W S Winston
2011-01-01
Much attention has in recent years been paid to fine applications of drug delivery systems, such as multiple emulsions, micro/nano solid lipid and polymer particles (spheres or capsules). Precise control of particle size and size distribution is especially important in such fine applications. Membrane emulsification can be used to prepare uniform-sized multiple emulsions and micro/nano particulates for drug delivery. It is a promising technique because of the better control of size and size distribution, the mildness of the process, the low energy consumption, easy operation and simple equipment, and amendable for large scale production. This review describes the state of the art of membrane emulsification in the preparation of monodisperse multiple emulsions and micro/nano particulates for drug delivery in recent years. The principles, influence of process parameters, advantages and disadvantages, and applications in preparing different types of drug delivery systems are reviewed. It can be concluded that the membrane emulsification technique in preparing emulsion/particulate products for drug delivery will further expand in the near future in conjunction with more basic investigations on this technique. Copyright © 2010 Wiley-Liss, Inc. and the American Pharmacists Association
NASA Astrophysics Data System (ADS)
Hullo, J.-F.; Thibault, G.; Boucheny, C.
2015-02-01
In a context of increased maintenance operations and workers generational renewal, a nuclear owner and operator like Electricité de France (EDF) is interested in the scaling up of tools and methods of "as-built virtual reality" for larger buildings and wider audiences. However, acquisition and sharing of as-built data on a large scale (large and complex multi-floored buildings) challenge current scientific and technical capacities. In this paper, we first present a state of the art of scanning tools and methods for industrial plants with very complex architecture. Then, we introduce the inner characteristics of the multi-sensor scanning and visualization of the interior of the most complex building of a power plant: a nuclear reactor building. We introduce several developments that made possible a first complete survey of such a large building, from acquisition, processing and fusion of multiple data sources (3D laser scans, total-station survey, RGB panoramic, 2D floor plans, 3D CAD as-built models). In addition, we present the concepts of a smart application developed for the painless exploration of the whole dataset. The goal of this application is to help professionals, unfamiliar with the manipulation of such datasets, to take into account spatial constraints induced by the building complexity while preparing maintenance operations. Finally, we discuss the main feedbacks of this large experiment, the remaining issues for the generalization of such large scale surveys and the future technical and scientific challenges in the field of industrial "virtual reality".
Horiguchi, Hiromasa; Yasunaga, Hideo; Hashimoto, Hideki; Ohe, Kazuhiko
2012-12-22
Secondary use of large scale administrative data is increasingly popular in health services and clinical research, where a user-friendly tool for data management is in great demand. MapReduce technology such as Hadoop is a promising tool for this purpose, though its use has been limited by the lack of user-friendly functions for transforming large scale data into wide table format, where each subject is represented by one row, for use in health services and clinical research. Since the original specification of Pig provides very few functions for column field management, we have developed a novel system called GroupFilterFormat to handle the definition of field and data content based on a Pig Latin script. We have also developed, as an open-source project, several user-defined functions to transform the table format using GroupFilterFormat and to deal with processing that considers date conditions. Having prepared dummy discharge summary data for 2.3 million inpatients and medical activity log data for 950 million events, we used the Elastic Compute Cloud environment provided by Amazon Inc. to execute processing speed and scaling benchmarks. In the speed benchmark test, the response time was significantly reduced and a linear relationship was observed between the quantity of data and processing time in both a small and a very large dataset. The scaling benchmark test showed clear scalability. In our system, doubling the number of nodes resulted in a 47% decrease in processing time. Our newly developed system is widely accessible as an open resource. This system is very simple and easy to use for researchers who are accustomed to using declarative command syntax for commercial statistical software and Structured Query Language. Although our system needs further sophistication to allow more flexibility in scripts and to improve efficiency in data processing, it shows promise in facilitating the application of MapReduce technology to efficient data processing with large scale administrative data in health services and clinical research.
NASA Astrophysics Data System (ADS)
Hasyim, Fuad; Subagio, Habib; Darmawan, Mulyanto
2016-06-01
A preparation of spatial planning documents require basic geospatial information and thematic accuracies. Recently these issues become important because spatial planning maps are impartial attachment of the regional act draft on spatial planning (PERDA). The needs of geospatial information in the preparation of spatial planning maps preparation can be divided into two major groups: (i). basic geospatial information (IGD), consist of of Indonesia Topographic maps (RBI), coastal and marine environmental maps (LPI), and geodetic control network and (ii). Thematic Geospatial Information (IGT). Currently, mostly local goverment in Indonesia have not finished their regulation draft on spatial planning due to some constrain including technical aspect. Some constrain in mapping of spatial planning are as follows: the availability of large scale ofbasic geospatial information, the availability of mapping guidelines, and human resources. Ideal conditions to be achieved for spatial planning maps are: (i) the availability of updated geospatial information in accordance with the scale needed for spatial planning maps, (ii) the guideline of mapping for spatial planning to support local government in completion their PERDA, and (iii) capacity building of local goverment human resources to completed spatial planning maps. The OMP strategies formulated to achieve these conditions are: (i) accelerating of IGD at scale of 1:50,000, 1: 25,000 and 1: 5,000, (ii) to accelerate mapping and integration of Thematic Geospatial Information (IGT) through stocktaking availability and mapping guidelines, (iii) the development of mapping guidelines and dissemination of spatial utilization and (iv) training of human resource on mapping technology.
NASA Astrophysics Data System (ADS)
Dubey, Vikas; Kaur, Jagjeet
2016-05-01
Present paper reports synthesis and characterization of trivalent cerium (Ce3+) doped zirconium dioxide (ZrO2) phosphors. Effect of variable concentration of cerium on photoluminescence (PL) is studied. Samples were prepared by combustion synthesis technique which is suitable for less time taking techniques also for large scale production for phosphors. Starting material used for sample preparation are Zr(NO3)3 and Ce(NO3)3 and urea used as a fuel. All prepared phosphor with variable concentration of Ce3+ (0.1 to 2mol%) was studied by photoluminescence analysis it is found that the excitation spectra of prepared phosphor shows broad excitation centred at 390nm. The excitation spectra with variable concentration of Ce3+ show strong peaks at 447nm. Spectrophotometric determinations of peaks are evaluated by Commission Internationale de I'Eclairage technique. Using this phosphor, the desired CIE values including emissions throughout the violet (390 nm) and blue (427 nm) of the spectra were achieved. Efficient blue light emitting diodes were fabricated using Ce3+ doped phosphor based on near ultraviolet (NUV) excited LED lights.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dubey, Vikas, E-mail: jsvikasdubey@gmail.com; Kaur, Jagjeet
Present paper reports synthesis and characterization of trivalent cerium (Ce{sup 3+}) doped zirconium dioxide (ZrO{sub 2}) phosphors. Effect of variable concentration of cerium on photoluminescence (PL) is studied. Samples were prepared by combustion synthesis technique which is suitable for less time taking techniques also for large scale production for phosphors. Starting material used for sample preparation are Zr(NO{sub 3}){sub 3} and Ce(NO{sub 3}){sub 3} and urea used as a fuel. All prepared phosphor with variable concentration of Ce{sup 3+} (0.1 to 2mol%) was studied by photoluminescence analysis it is found that the excitation spectra of prepared phosphor shows broad excitationmore » centred at 390nm. The excitation spectra with variable concentration of Ce{sup 3+} show strong peaks at 447nm. Spectrophotometric determinations of peaks are evaluated by Commission Internationale de I’Eclairage technique. Using this phosphor, the desired CIE values including emissions throughout the violet (390 nm) and blue (427 nm) of the spectra were achieved. Efficient blue light emitting diodes were fabricated using Ce{sup 3+} doped phosphor based on near ultraviolet (NUV) excited LED lights.« less
Thermal exploitation of wastes with lignite for energy production.
Grammelis, Panagiotis; Kakaras, Emmanuel; Skodras, George
2003-11-01
The thermal exploitation of wastewood with Greek lignite was investigated by performing tests in a laboratory-scale fluidized bed reactor, a 1-MW(th) semi-industrial circulating fluidized bed combustor, and an industrial boiler. Blends of natural wood, demolition wood, railroad sleepers, medium-density fiberboard residues, and power poles with lignite were used, and the co-combustion efficiency and the effect of wastewood addition on the emitted pollutants were investigated. Carbon monoxide, sulfur dioxide, and oxides of nitrogen emissions were continuously monitored, and, during the industrial-scale tests, the toxic emissions (polychlorinated dibenzodioxins and dibenzofurans and heavy metals) were determined. Ash samples were analyzed for heavy metals in an inductively coupled plasma-atomic emission spectroscopy spectrophotometer. Problems were observed during the preparation of wastewood, because species embedded with different compounds, such as railway sleepers and demolition wood, were not easily treated. All wastewood blends were proven good fuels; co-combustion proceeded smoothly and homogeneous temperature and pressure profiles were obtained. Although some fluctuations were observed, low emissions of gaseous pollutants were obtained for all fuel blends. The metal element emissions (in the flue gases and the solid residues) were lower than the legislative limits. Therefore, wastewood co-combustion with lignite can be realized, provided that the fuel handling and preparation can be practically performed in large-scale installations.
Cagnetta, Giovanni; Huang, Jun; Lomovskiy, Igor O; Yu, Gang
2017-11-01
Zero-valent iron (ZVI) is a valuable material for environmental remediation, because of its safeness, large availability, and inexpensiveness. Moreover, its reactivity can be improved by addition of (nano-) particles of other elements such as noble metals. However, common preparation methods for this kind of iron-based composites involve wet precipitation of noble metal salt precursors, so they are often expensive and not green. Mechanochemical procedures can provide a solvent-free alternative, even at a large scale. The present study demonstrates that it is possible to tailor functional properties of ZVI-based materials, utilizing high-energy ball milling. All main preparation parameters are investigated and discussed. Specifically, a copper-carbon-iron ternary composite was prepared for fast degradation of 4-nitrophenol (utilized as model pollutant) to 4-aminophenol and other phenolic compounds. Copper and carbon are purposely chosen to insert specific properties to the composite: Copper acts as efficient nano-cathode that enhances electron transfer from iron to 4-nitrophenol, while carbon protects the iron surface from fast oxidation in open air. In this way, the reactive material can rapidly reduce high concentration of nitrophenols in water, it does not require acid washing to be activated, and can be stored in open air for one week without any significant activity loss.
WEST-3 wind turbine simulator development
NASA Technical Reports Server (NTRS)
Hoffman, J. A.; Sridhar, S.
1985-01-01
The software developed for WEST-3, a new, all digital, and fully programmable wind turbine simulator is given. The process of wind turbine simulation on WEST-3 is described in detail. The major steps are, the processing of the mathematical models, the preparation of the constant data, and the use of system software generated executable code for running on WEST-3. The mechanics of reformulation, normalization, and scaling of the mathematical models is discussed in detail, in particulr, the significance of reformulation which leads to accurate simulations. Descriptions for the preprocessor computer programs which are used to prepare the constant data needed in the simulation are given. These programs, in addition to scaling and normalizing all the constants, relieve the user from having to generate a large number of constants used in the simulation. Also given are brief descriptions of the components of the WEST-3 system software: Translator, Assembler, Linker, and Loader. Also included are: details of the aeroelastic rotor analysis, which is the center of a wind turbine simulation model, analysis of the gimbal subsystem; and listings of the variables, constants, and equations used in the simulation.
Survey of lift-fan aerodynamic technology
NASA Technical Reports Server (NTRS)
Hickey, David H.; Kirk, Jerry V.
1993-01-01
Representatives of NASA Ames Research Center asked that a summary of technology appropriate for lift-fan powered short takeoff/vertical landing (STOVL) aircraft be prepared so that new programs could more easily benefit from past research efforts. This paper represents one of six prepared for that purpose. The authors have conducted or supervised the conduct of research on lift-fan powered STOVL designs and some of their important components for decades. This paper will first address aerodynamic modeling requirements for experimental programs to assure realistic, trustworthy results. It will next summarize the results or efforts to develop satisfactory specialized STOVL components such as inlets and flow deflectors. It will also discuss problems with operation near the ground, aerodynamics while under lift-fan power, and aerodynamic prediction techniques. Finally, results of studies to reduce lift-fan noise will be presented. The paper will emphasize results from large scale experiments, where available, for reasons that will be brought out in the discussion. Some work with lift-engine powered STOVL aircraft is also applicable to lift-fan technology and will be presented herein. Small-scale data will be used where necessary to fill gaps.
Kamarei, Fahimeh; Vajda, Péter; Guiochon, Georges
2013-09-20
This paper compares two methods used for the preparative purification of a mixture of (S)-, and (R)-naproxen on a Whelk-O1 column, using either high performance liquid chromatography or supercritical fluid chromatography. The adsorption properties of both enantiomers were measured by frontal analysis, using methanol-water and methanol-supercritical carbon dioxide mixtures as the mobile phases. The measured adsorption data were modeled, providing the adsorption isotherms and their parameters, which were derived from the nonlinear fit of the isotherm models to the experimental data points. The model used was a Bi-Langmuir isotherm, similar to the model used in many enantiomeric separations. These isotherms were used to calculate the elution profiles of overloaded elution bands, assuming competitive Bi-Langmuir behavior of the two enantiomers. The analysis of these profiles provides the basis for a comparison between supercritical fluid chromatographic and high performance liquid chromatographic preparative scale separations. It permits an illustration of the advantages and disadvantages of these methods and a discussion of their potential performance. Copyright © 2013 Elsevier B.V. All rights reserved.
Zhang, Yunlu; Gao, Qiuming; Lin, Zhi; Zhang, Tao; Xu, Jiandong; Tan, Yanli; Tian, Weiqian; Jiang, Lei
2014-01-01
Metal organic framework (MOF) materials have attracted great attention due to their well-ordered and controllable pores possessing of prominent potentials for gas molecule sorption and separation performances. Organizing the MOF crystals to a continuous membrane with a certain scale will better exhibit their prominent potentials. Reports in recent years concentrate on well grown MOF membranes on specific substrates. Free standing MOF membranes could have more important applications since they are independent from the substrates. However, the method to prepare such a membrane has been a great challenge because good mechanical properties and stabilities are highly required. Here, we demonstrate a novel and facile technique for preparing the free standing membrane with a size as large as centimeter scale. The substrate we use proved itself not only a good skeleton but also an excellent precursor to fulfill the reaction. This kind of membrane owns a strong mechanical strength, based on the fact that it is much thinner than the composite membranes grown on substrates and it could exhibit good property of gas separation. PMID:24821299
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
Ten major studies are included in this report; a separate abstract was prepared for each. In addition, there are 4 appendices related to reliability, namely: (A) Load and Generation Uncertainty, by Norton Savage, DOE; (B) Comparison of Service-Interruption Cost Studies, by Dr. Gay Lamb, DOE; (C) Impact of Large-Scale Fuel-Supply Disruptions on Regional Electric-Power Reliability, by Anthony J. Como and Mark Gielecki, DOE; and (D) Reliability Effects of the 1980 Florida Conservation Act, by William E. Scott and Thomas R. Hitz, Jr., DOE. (LCL)
CNTs grown on nanoporous carbon from zeolitic imidazolate frameworks for supercapacitors.
Kim, Jeonghun; Young, Christine; Lee, Jaewoo; Park, Min-Sik; Shahabuddin, Mohammed; Yamauchi, Yusuke; Kim, Jung Ho
2016-10-27
Carbon nanotubes (CNT) grown on nanoporous carbon (NPC), which yields coexisting amorphous and graphitic nanoarchitectures, have been prepared on a large scale from zeolitic imidazolate framework (ZIF) by introducing bimetallic ions (Co 2+ and Zn 2+ ). Interestingly, the hybrid Co/Zn-ZIF-derived NPC showed rich graphitic CNTs on the surface. This NPC was utilized for a coin-type supercapacitor cell with an aqueous electrolyte, which showed enhanced retention at high current density and good stability over 10 000 cycles.
Synthesis of acrylic polymer beads for solid-supported proline-derived organocatalysts.
Kristensen, Tor E; Vestli, Kristian; Fredriksen, Kim A; Hansen, Finn K; Hansen, Tore
2009-07-16
A completely non-chromatographic and highly large-scale adaptable synthesis of acrylic polymer beads containing proline and prolineamides has been developed. Novel monomeric proline (meth)acrylates are prepared from hydroxyproline in only one step. Free-radical copolymerization then gives solid-supported proline organocatalysts directly in as little as two steps overall, without using any prefabricated solid supports, by using either droplet or dispersion polymerization. These affordable acrylic beads have highly favorable and adjustable swelling characteristics and are excellent reusable catalysts for organocatalytic reactions.
Topham, C M; Dalziel, K
1986-01-01
[2-18O]Ribulose 5-phosphate was prepared and shown to be converted enzymically by 6-phosphogluconate dehydrogenase from sheep liver into 6-phosphogluconate with complete retention of the heavy isotope. This finding unequivocally excludes the possibility of a Schiff-base mechanism for the enzyme. The involvement of metal ions has already been excluded, and other possible mechanisms are discussed. The enzyme was purified by an improved large-scale procedure, which is briefly described. PMID:3718491
Demonstration of Regenerable, Large-Scale Ion Exchange System Using WBA Resin in Rialto, CA
2012-12-01
requirements. The system also has the flexibility to manually modify system parameters such as flow rates, pH set points, time cycles, etc. The system... flexibility to produce soda ash solutions that vary in concentration from 1 to 10% dry soda ash. The packaged soda ash system was engineered and...The dry soda ash was conveyed to a storage hopper (39.5 ft3) using a flexible screw conveyer. Soda ash solutions were prepared in a 100 gallon
Zhou, Yu; Guo, Huajun; Yan, Guochun; Wang, Zhixing; Li, Xinhai; Yang, Zhewei; Zheng, Anxiong; Wang, Jiexi
2018-04-10
A facile and large-scale fluidized bed reaction route was introduced for the first time to prepare crystalline embedded amorphous silicon nanoparticles with an average size of 50 nm as anode materials for lithium-ion batteries. By increasing the operating potential to control the electrochemically active degree, the resulting sample showed excellent cycle stability with a high capacity retention of 94.7% after 200 cycles at 1 A g-1 in the voltage range of 0.12-2.00 V.
Refurbishment of SRB aluminum components by walnut hull blast removal of protective coatings
NASA Technical Reports Server (NTRS)
Colberg, W. R.; Gordon, G. H.; Jackson, C. H.
1982-01-01
A test program was conducted to develop, optimize, and scale up an abrasive blasting procedure was developed for refurbishment of specific SRB components: aft skirt, forward skirt, frustrum, and painted piece parts. Test specimens utilizing 2219 T87 aluminum substrate of varying thicknesses were prepared and blasted at progressively increasing pressures with selected abrasives. Specimens were analyzed for material response. The optimum blasting parameters were determined on panel specimens and verified on a large cylindrical integrated test bed.
Polymer Dispersed Liquid Crystal Displays
NASA Astrophysics Data System (ADS)
Doane, J. William
The following sections are included: * INTRODUCTION AND HISTORICAL DEVELOPMENT * PDLC MATERIALS PREPARATION * Polymerization induced phase separation (PIPS) * Thermally induced phase separation (TIPS) * Solvent induced phase separation (SIPS) * Encapsulation (NCAP) * RESPONSE VOLTAGE * Dielectric and resistive effects * Radial configuration * Bipolar configuration * Other director configurations * RESPONSE TIME * DISPLAY CONTRAST * Light scattering and index matching * Incorporation of dyes * Contrast measurements * PDLC DISPLAY DEVICES AND INNOVATIONS * Reflective direct view displays * Large-scale, flexible displays * Switchable windows * Projection displays * High definition spatial light modulator * Haze-free PDLC shutters: wide angle view displays * ENVIRONMENTAL STABILITY * ACKNOWLEDGEMENTS * REFERENCES
Quantitative mapping of rainfall rates over the oceans utilizing Nimbus-5 ESMR data
NASA Technical Reports Server (NTRS)
Rao, M. S. V.; Abbott, W. V.
1976-01-01
The electrically scanning microwave radiometer (ESMR) data from the Nimbus 5 satellite was used to deduce estimates of precipitation amount over the oceans. An atlas of the global oceanic rainfall was prepared and the global rainfall maps analyzed and related to available ground truth information as well as to large scale processes in the atmosphere. It was concluded that the ESMR system provides the most reliable and direct approach yet known for the estimation of rainfall over sparsely documented, wide oceanic regions.
22 GHz VLBI Survey: Status Report and Preliminary Results
NASA Technical Reports Server (NTRS)
Moellenbrock, G.; Fujisawa, K.; Preston, R.; Gurvits, L.; Dewey, R.; Hirabayashi, H.; Inoue, M.; Jauncey, D.; Migenes, V.; Roberts, D.;
1994-01-01
A ground-based VLBI survey to measure the visibilities and correlated flux densities in continuum at 22 GHz of more than 140 extragalactic radio sources has been conducted with baselines up to approximately 11 000 km. The project has been designed to help in preparation of target lists for VSOP and Radioastron Space VLBI missions as well as providing observational data for statistical study of structural properties at 22 GHz on sub-milliarcsecond scales for this large sample of extragalactic sources.
Inverse problems in the design, modeling and testing of engineering systems
NASA Technical Reports Server (NTRS)
Alifanov, Oleg M.
1991-01-01
Formulations, classification, areas of application, and approaches to solving different inverse problems are considered for the design of structures, modeling, and experimental data processing. Problems in the practical implementation of theoretical-experimental methods based on solving inverse problems are analyzed in order to identify mathematical models of physical processes, aid in input data preparation for design parameter optimization, help in design parameter optimization itself, and to model experiments, large-scale tests, and real tests of engineering systems.
2010-09-01
working with equally experienced partners who can, cumulatively, help each other make sense of chaotic situations. “Human brains collect, organize...but a process reinforced by years of Fire Department training. No matter what we do, even an optimally functioning human brain will prepare for...trick or reorganize the brain of those who will be first responding incident commanders to an edge-of-chaos event into creatively making sense of
Cook, Brian L.; Steuerwald, Dirk; Kaiser, Liselotte; Graveland-Bikker, Johanna; Vanberghem, Melanie; Berke, Allison P.; Herlihy, Kara; Pick, Horst; Vogel, Horst; Zhang, Shuguang
2009-01-01
Although understanding of the olfactory system has progressed at the level of downstream receptor signaling and the wiring of olfactory neurons, the system remains poorly understood at the molecular level of the receptors and their interaction with and recognition of odorant ligands. The structure and functional mechanisms of these receptors still remain a tantalizing enigma, because numerous previous attempts at the large-scale production of functional olfactory receptors (ORs) have not been successful to date. To investigate the elusive biochemistry and molecular mechanisms of olfaction, we have developed a mammalian expression system for the large-scale production and purification of a functional OR protein in milligram quantities. Here, we report the study of human OR17-4 (hOR17-4) purified from a HEK293S tetracycline-inducible system. Scale-up of production yield was achieved through suspension culture in a bioreactor, which enabled the preparation of >10 mg of monomeric hOR17-4 receptor after immunoaffinity and size exclusion chromatography, with expression yields reaching 3 mg/L of culture medium. Several key post-translational modifications were identified using MS, and CD spectroscopy showed the receptor to be ≈50% α-helix, similar to other recently determined G protein-coupled receptor structures. Detergent-solubilized hOR17-4 specifically bound its known activating odorants lilial and floralozone in vitro, as measured by surface plasmon resonance. The hOR17-4 also recognized specific odorants in heterologous cells as determined by calcium ion mobilization. Our system is feasible for the production of large quantities of OR necessary for structural and functional analyses and research into OR biosensor devices. PMID:19581598
Cook, Brian L; Steuerwald, Dirk; Kaiser, Liselotte; Graveland-Bikker, Johanna; Vanberghem, Melanie; Berke, Allison P; Herlihy, Kara; Pick, Horst; Vogel, Horst; Zhang, Shuguang
2009-07-21
Although understanding of the olfactory system has progressed at the level of downstream receptor signaling and the wiring of olfactory neurons, the system remains poorly understood at the molecular level of the receptors and their interaction with and recognition of odorant ligands. The structure and functional mechanisms of these receptors still remain a tantalizing enigma, because numerous previous attempts at the large-scale production of functional olfactory receptors (ORs) have not been successful to date. To investigate the elusive biochemistry and molecular mechanisms of olfaction, we have developed a mammalian expression system for the large-scale production and purification of a functional OR protein in milligram quantities. Here, we report the study of human OR17-4 (hOR17-4) purified from a HEK293S tetracycline-inducible system. Scale-up of production yield was achieved through suspension culture in a bioreactor, which enabled the preparation of >10 mg of monomeric hOR17-4 receptor after immunoaffinity and size exclusion chromatography, with expression yields reaching 3 mg/L of culture medium. Several key post-translational modifications were identified using MS, and CD spectroscopy showed the receptor to be approximately 50% alpha-helix, similar to other recently determined G protein-coupled receptor structures. Detergent-solubilized hOR17-4 specifically bound its known activating odorants lilial and floralozone in vitro, as measured by surface plasmon resonance. The hOR17-4 also recognized specific odorants in heterologous cells as determined by calcium ion mobilization. Our system is feasible for the production of large quantities of OR necessary for structural and functional analyses and research into OR biosensor devices.
2018-05-01
Packing light is the idea behind the Zero Launch Mass 3-D Printer. Instead of loading up on heavy building supplies, a large scale 3-D printer capable of using recycled plastic waste and dirt at the destination as construction material would save mass and money when launching robotic precursor missions to build infrastructure on the Moon or Mars in preparation for human habitation. To make this a reality, Nathan Gelino, a researcher engineer with NASA’s Swamp Works at Kennedy Space Center, measured the temperature of a test specimen from the 3-D printer Tuesday as an early step in characterizing printed material strength properties. Material temperature plays a large role in the strength of bonds between layers.
Preparation and characterization of oriented silica nanowires
NASA Astrophysics Data System (ADS)
Sun, S. H.; Meng, G. W.; Zhang, M. G.; Tian, Y. T.; Xie, T.; Zhang, L. D.
2003-11-01
Large-scale of oriented closely packed silica nanowire bunches have been synthesized by using large size (1-10 μm in diameter), low melting point tin droplets as catalyst on silicon wafers at 980 °C. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses show that the amorphous silica nanowires have lengths of 50-100 μm and diameters of 100-200 nm. Unlike any previous observed results using high melting point metal (such as gold and iron) as catalyst, the Sn catalyst growth exhibits many interesting phenomena. Each Sn ball can simultaneously catalyze the growth of many silica nanowires, which is quite different from the conventional vapor-liquid-solid process.
Preparation of fosmid libraries and functional metagenomic analysis of microbial community DNA.
Martínez, Asunción; Osburne, Marcia S
2013-01-01
One of the most important challenges in contemporary microbial ecology is to assign a functional role to the large number of novel genes discovered through large-scale sequencing of natural microbial communities that lack similarity to genes of known function. Functional screening of metagenomic libraries, that is, screening environmental DNA clones for the ability to confer an activity of interest to a heterologous bacterial host, is a promising approach for bridging the gap between metagenomic DNA sequencing and functional characterization. Here, we describe methods for isolating environmental DNA and constructing metagenomic fosmid libraries, as well as methods for designing and implementing successful functional screens of such libraries. © 2013 Elsevier Inc. All rights reserved.
Automated in-line mixing system for large scale production of chitosan-based polyplexes.
Tavakoli Naeini, Ashkan; Soliman, Ousamah Younoss; Alameh, Mohamad Gabriel; Lavertu, Marc; Buschmann, Michael D
2017-08-15
Chitosan (CS)-based polyplexes are efficient non-viral gene delivery systems that are most commonly prepared by manual mixing. However, manual mixing is not only poorly controlled but also restricted to relatively small preparation volumes, limiting clinical applications. In order to overcome these drawbacks and to produce clinical quantities of CS-based polyplexes, a fully automated in-line mixing platform was developed for production of large batches of small-size and homogeneous CS-based polyplexes. Operational conditions to produce small-sized homogeneous polyplexes were identified. Increasing mixing concentrations of CS and nucleic acid was directly associated with an increase in size and polydispersity of both CS/pDNA and CS/siRNA polyplexes. We also found that although the speed of mixing has a negligible impact on the properties of CS/pDNA polyplexes, the size and polydispersity of CS/siRNA polyplexes are strongly influenced by the mixing speed: the higher the speed, the smaller the size and polydispersity. While in-line and manual CS/pDNA polyplexes had similar size and PDI, CS/siRNA polyplexes were smaller and more homogenous when prepared in-line in the non-laminar flow regime compared to manual method. Finally, we found that in-line mixed CS/siRNA polyplexes have equivalent or higher silencing efficiency of ApoB in HepG2 cells, compared to manually prepared polyplexes. Copyright © 2017 Elsevier Inc. All rights reserved.
Li, Chen; Habler, Gerlinde; Baldwin, Lisa C; Abart, Rainer
2018-01-01
Focused ion beam (FIB) sample preparation technique in plan-view geometry allows direct correlations of the atomic structure study via transmission electron microscopy with micrometer-scale property measurements. However, one main technical difficulty is that a large amount of material must be removed underneath the specimen. Furthermore, directly monitoring the milling process is difficult unless very large material volumes surrounding the TEM specimen site are removed. In this paper, a new cutting geometry is introduced for FIB lift-out sample preparation with plan-view geometry. Firstly, an "isolated" cuboid shaped specimen is cut out, leaving a "bridge" connecting it with the bulk material. Subsequently the two long sides of the "isolated" cuboid are wedged, forming a triangular prism shape. A micromanipulator needle is used for in-situ transfer of the specimen to a FIB TEM grid, which has been mounted parallel with the specimen surface using a simple custom-made sample slit. Finally, the grid is transferred to the standard FIB grid holder for final thinning with standard procedures. This new cutting geometry provides clear viewing angles for monitoring the milling process, which solves the difficulty of judging whether the specimen has been entirely detached from the bulk material, with the least possible damage to the surrounding materials. With an improved success rate and efficiency, this plan-view FIB lift-out specimen preparation technique should have a wide application for material science. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
YU,KUI; BRINKER,C. JEFFREY; HURD,ALAN J.
2000-11-22
Since the discovery of surfactant-templated silica by Mobil scientists in 1992, mesostructured silica has been synthesized in various forms including thin films, powders, particles, and fibers. In general, mesostructured silica has potential applications, such as in separation, catalysis, sensors, and fluidic microsystems. In respect to these potential applications, mesostructured silica in the form of thin films is perhaps one of the most promising candidates. The preparation of mesostructured silica films through preferential solvent evaporation-induced self-assembly (EISA) has recently received much attention in the laboratories. However, no amphiphile/silica films with reverse mesophases have ever been made through this EISA procedure. Furthermore,more » templates employed to date have been either surfactants or poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) triblock copolymers, such as pluronic P-123, both of which are water-soluble and alcohol-soluble. Due to their relatively low molecular weight, the templated silica films with mesoscopic order have been limited to relatively small characteristic length scales. In the present communication, the authors report a novel synthetic method to prepare mesostructured amphiphilic/silica films with regular and reverse mesophases of large characteristic length scales. This method involves evaporation-induced self-assembly (EISA) of amphiphilic polystyrene-block-poly(ethylene oxide) (PS-b-PEO) diblock copolymers. In the present study, the PS-b-PEO diblocks are denoted as, for example, PS(215)-b-PEO(100), showing that this particular sample contains 215 S repeat units and 100 EO repeat units. This PS(215)-b-PEO(100) diblock possesses high molecular weight and does not directly mix with water or alcohol. To the authors knowledge, no studies have reported the use of water-insoluble and alcohol-insoluble amphiphilic diblocks as structure-directing agents in the synthesis of mesostructured silica films through EISA. It is believed that the present system is the first to yield amphiphile/silica films with regular and reverse mesophases, as well as curved multi-bilayer mesostructures, through EISA. The ready formation of the diblock/silica films with multi-bilayer vesicular mesostructures is discussed.« less
2015-01-01
Summary Amino acids, whether natural, semisynthetic or synthetic, are among the most important and useful chiral building blocks available for organic chemical synthesis. In principle, they can function as inexpensive, chiral and densely functionalized starting materials. On the other hand, the use of amino acid starting materials routinely necessitates protective group chemistry, and in reality, large-scale preparations of even the simplest side-chain derivatives of many amino acids often become annoyingly strenuous due to the necessity of employing protecting groups, on one or more of the amino acid functionalities, during the synthetic sequence. However, in the case of hydroxyamino acids such as hydroxyproline, serine, threonine, tyrosine and 3,4-dihydroxyphenylalanine (DOPA), many O-acyl side-chain derivatives are directly accessible via a particularly expedient and scalable method not commonly applied until recently. Direct acylation of unprotected hydroxyamino acids with acyl halides or carboxylic anhydrides under appropriately acidic reaction conditions renders possible chemoselective O-acylation, furnishing the corresponding side-chain esters directly, on multigram-scale, in a single step, and without chromatographic purification. Assuming a certain degree of stability under acidic reaction conditions, the method is also applicable for a number of related compounds, such as various amino alcohols and the thiol-functional amino acid cysteine. While the basic methodology underlying this approach has been known for decades, it has evolved through recent developments connected to amino acid-derived chiral organocatalysts to become a more widely recognized procedure for large-scale preparation of many useful side-chain derivatives of hydroxyamino acids and related compounds. Such derivatives are useful in peptide chemistry and drug development, as amino acid amphiphiles for asymmetric catalysis, and as amino acid acrylic precursors for preparation of catalytically active macromolecular networks in the form of soluble polymers, crosslinked polymer beads or nanoparticulate systems. The objective of the present review is to increase awareness of the existence and convenience of this methodology, assess its competitiveness compared to newer and more elaborate procedures for chemoselective O-acylation reactions, spur its further development, and finally to chronicle the informative, but poorly documented history of its development. PMID:25977719
Li, Aifeng; Sun, Ailing; Liu, Renmin; Zhang, Yongqing; Cui, Jichun
2014-08-15
In this study, a simple and efficient preparative procedure was developed for preparation of seven flavonoids from the peel of Trichosanthes kirilowii Maxim. using polyamide resin followed by semi-preparative high performance liquid chromatography (SPHPLC). First, the ethyl acetate fraction from the peel of T. kirilowii Maxim. obtained "prefractionation" using polyamide resin, which yielded two subfractions. And then the two subfractions were isolated by SPHPLC with an isocratic elution of methanol-water. Finally, seven known flavonoids were purified from 35 g of ethyl acetate extract including quercetin-3-O-[α-l-rhamnose (1→2)-β-d-glucopyranosyl]-5-O-β-d-glucopyranoside (19 mg), quercetin-3-O-rutinoside (24 mg), apigenin-7-O-β-d-glucopyranoside (10mg), diosmetin-7-O-β-d-glucopyranoside (45 mg), luteolin (21 mg), apigenin (15 mg), and diosmetin (56 mg). The purities of the compounds were determined by HPLC and the chemical structures were confirmed by UV and NMR analysis. In the present study, a simple, effective, and rapid procedure was established for preparative separation of multiple components from the peel of T. kirilowii Maxim. Furthermore, it was scalable and economical, so it was a promising basis for large-scale preparation of flavonoids from other plant extracts. Copyright © 2014. Published by Elsevier B.V.
NASA Astrophysics Data System (ADS)
Feng, Tianjiao; Wei, Wei; Chen, Liding; Yu, Yang
2017-04-01
In the dryland regions, soil moisture is the main factor to determine vegetation growth and ecosystem restoration. Land preparation and vegetation restoration are the principal means for improving soil water content(SWC). Thus, it is important to analyze the coupling role of these two means on soil moisture. In this study, soil moisture were monitored at a semi-arid loess hilly catchment of China, during the growing season of 2014 and 2015. Four different land preparation methods (level ditches, fish-scale pits, adverse grade tablelands and level benches)and vegetation types(Prunus armeniaca, Platycladus orientalis, Platycladus orientalis and Caragana microphylla) were included in the experimental design. Our results showed that: (1)Soil moisture content differed across land preparation types, which is higher for fish-scale pits and decreased in the order of level ditches and adverse grade tablelands.(2) Rainwater harvesting capacity of fish-scale pits is greater than adverse grade tablelands. However the water holding capacity is much higher at soils prepared with the adverse grade tablelands method than the ones prepared by fish-scale pits methods. (3) When land preparation method is similar, vegetation play a key role in soil moisture variation. For example, the mean soil moisture under a Platycladus orientalis field is 26.72% higher than a Pinus tabulaeformis field, with the same land preparation methods. (4)Soil moisture in deeper soil layers is more affected by changes in the vegetation cover while soil moisture in the shallower layers is more affected by the variation in the land preparation methods. Therefore, we suggest that vegetation types such as: Platycladus orientalisor as well as soil preparation methods such as level ditch and fish-scale pit are the most appropriate vegetation cover and land preparation methods for landscape restoration in semi-arid loess hilly area. This conclusion was made based on the vegetation type and land preparation with the best water-holding capacity.
Lin, Li; Xu, Xiang; Yin, Jianbo; Sun, Jingyu; Tan, Zhenjun; Koh, Ai Leen; Wang, Huan; Peng, Hailin; Chen, Yulin; Liu, Zhongfan
2016-07-13
Being atomically thin, graphene-based p-n junctions hold great promise for applications in ultrasmall high-efficiency photodetectors. It is well-known that the efficiency of such photodetectors can be improved by optimizing the chemical potential difference of the graphene p-n junction. However, to date, such tuning has been limited to a few hundred millielectronvolts. To improve this critical parameter, here we report that using a temperature-controlled chemical vapor deposition process, we successfully achieved modulation-doped growth of an alternately nitrogen- and boron-doped graphene p-n junction with a tunable chemical potential difference up to 1 eV. Furthermore, such p-n junction structure can be prepared on a large scale with stable, uniform, and substitutional doping and exhibits a single-crystalline nature. This work provides a feasible method for synthesizing low-cost, large-scale, high efficiency graphene p-n junctions, thus facilitating their applications in optoelectronic and energy conversion devices.
Progress and future tasks in food irradiation
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
1973-09-01
Progress in the use of atomic energy for preserving food was reviewed at recent meetings of the Second International Symposium on Food Irradiation in India. The technical feasibility of radiation control was discussed with regard to the inhibition of sprouting in yams by gamma radiation; combined radiation and chemical treatment of potatoes and onions to prevent sprouting; effects of radiation on starch preparations and seasonings; radiation preservation of fish; radiation effects on bacteria; and control of insect pests. The importance of assessing the economic feasibility on the basis of practical, large-scale tests is emphasized. With regard to wholesomeness reports weremore » given of acute and chronic toxicity tests with irradiated wheat, shrimp, whole diets, beef, strawberries, mushrooms, and chicken. No harmful effects were observed following large-scale animal testing of irradiated complete diets. A summary of tasks ahead includes an assessment of economic benefits of food irradiation; criteria of public health acceptance; education of the public; and internationsl collaboration with the FAO and IAEA. (HLW)« less
Large-scale patterns formed by solar active regions during the ascending phase of cycle 21
NASA Astrophysics Data System (ADS)
Gaizauskas, V.; Harvey, K. L.; Harvey, J. W.; Zwaan, C.
1983-02-01
Synoptic maps of photospheric magnetic fields prepared at the Kitt Peak National Observatory are used in investigating large-scale patterns in the spatial and temporal distribution of solar active regions for 27 solar rotations between 1977 and 1979. The active regions are found to be distributed in 'complexes of activity' (Bumba and Howard, 1965). With the working definition of a complex of activity based on continuity and proximity of the constituent active regions, the phenomenology of complexes is explored. It is found that complexes of activity form within one month and that they are typically maintained for 3 to 6 solar rotations by fresh injections of magnetic flux. During the active lifetime of a complex of activity, the total magnetic flux in the complex remains steady to within a factor of 2. The magnetic polarities are closely balanced, and each complex rotates about the sun at its own special, constant rate. In certain cases, the complexes form two diverging branches.
Diaconescu, Bogdan; Nenchev, Georgi; de la Figuera, Juan; Pohl, Karsten
2007-10-01
We describe the design and performance of a fast-scanning, variable temperature scanning tunneling microscope (STM) operating from 80 to 700 K in ultrahigh vacuum (UHV), which routinely achieves large scale atomically resolved imaging of compact metallic surfaces. An efficient in-vacuum vibration isolation and cryogenic system allows for no external vibration isolation of the UHV chamber. The design of the sample holder and STM head permits imaging of the same nanometer-size area of the sample before and after sample preparation outside the STM base. Refractory metal samples are frequently annealed up to 2000 K and their cooldown time from room temperature to 80 K is 15 min. The vertical resolution of the instrument was found to be about 2 pm at room temperature. The coarse motor design allows both translation and rotation of the scanner tube. The total scanning area is about 8 x 8 microm(2). The sample temperature can be adjusted by a few tens of degrees while scanning over the same sample area.
NASA Astrophysics Data System (ADS)
Dai, LongGui; Yang, Fan; Yue, Gen; Jiang, Yang; Jia, Haiqiang; Wang, Wenxin; Chen, Hong
2014-11-01
Generally, nano-scale patterned sapphire substrate (NPSS) has better performance than micro-scale patterned sapphire substrate (MPSS) in improving the light extraction efficiency of LEDs. Laser interference lithography (LIL) is one of the powerful fabrication methods for periodic nanostructures without photo-masks for different designs. However, Lloyd's mirror LIL system has the disadvantage that fabricated patterns are inevitably distorted, especially for large-area twodimensional (2D) periodic nanostructures. Herein, we introduce two-beam LIL system to fabricate consistent large-area NPSS. Quantitative analysis and characterization indicate that the high uniformity of the photoresist arrays is achieved. Through the combination of dry etching and wet etching techniques, the well-defined NPSS with period of 460 nm were prepared on the whole sapphire substrate. The deviation is 4.34% for the bottom width of the triangle truncated pyramid arrays on the whole 2-inch sapphire substrate, which is suitable for the application in industrial production of NPSS.
Ion conducting membranes for aqueous flow battery systems.
Yuan, Zhizhang; Zhang, Huamin; Li, Xianfeng
2018-06-07
Flow batteries, aqueous flow batteries in particular, are the most promising candidates for stationary energy storage to realize the wide utilization of renewable energy sources. To meet the requirement of large-scale energy storage, there has been a growing interest in aqueous flow batteries, especially in novel redox couples and flow-type systems. However, the development of aqueous flow battery technologies is at an early stage and their performance can be further improved. As a key component of a flow battery, the membrane has a significant effect on battery performance. Currently, the membranes used in aqueous flow battery technologies are very limited. In this feature article, we first cover the application of porous membranes in vanadium flow battery technology, and then the membranes in most recently reported aqueous flow battery systems. Meanwhile, we hope that this feature article will inspire more efforts to design and prepare membranes with outstanding performance and stability, and then accelerate the development of flow batteries for large scale energy storage applications.
Bioinspired greigite magnetic nanocrystals: chemical synthesis and biomedicine applications
Feng, Mei; Lu, Yang; Yang, Yuan; Zhang, Meng; Xu, Yun-Jun; Gao, Huai-Ling; Dong, Liang; Xu, Wei-Ping; Yu, Shu-Hong
2013-01-01
Large scale greigite with uniform dimensions has stimulated significant demands for applications such as hyperthermia, photovoltaics, medicine and cell separation, etc. However, the inhomogeneity and hydrophobicity for most of the as prepared greigite crystals has limited their applications in biomedicine. Herein, we report a green chemical method utilizing β-cyclodextrin (β-CD) and polyethylene glycol (PEG) to synthesize bioinspired greigite (Fe3S4) magnetic nanocrystals (GMNCs) with similar structure and magnetic property of magnetosome in a large scale. β-CD and PEG is responsible to control the crystal phase and morphology, as well as to bound onto the surface of nanocrystals and form polymer layers. The GMNCs exhibit a transverse relaxivity of 94.8 mM−1s−1 which is as high as iron oxide nanocrystals, and an entrapment efficiency of 58.7% for magnetic guided delivery of chemotherapeutic drug doxorubicin. Moreover, enhanced chemotherapeutic treatment of mice tumor was obtained via intravenous injection of doxorubicin loaded GMNCs. PMID:24141204
NASA Astrophysics Data System (ADS)
Chen, Yu; Wang, Qihua; Wang, Tingmei
2015-10-01
The core-shell structured mesoporous silica nanomaterials (MSNs) are experiencing rapid development in many applications such as heterogeneous catalysis, bio-imaging and drug delivery wherein a large pore volume is desirable. We develop a one-pot method for large-scale synthesis of brain-like mesoporous silica nanocomposites based on the reasonable change of the intrinsic nature of the -Si-O-Si- framework of silica nanoparticles together with a selective etching strategy. The as-synthesized products show good monodispersion and a large pore volume of 1.0 cm3 g-1. The novelty of this approach lies in the use of an inorganic-organic hybrid layer to assist the creation of large-pore morphology on the outermost shell thereby promoting efficient mass transfer or storage. Importantly, the method is reliable and grams of products can be easily prepared. The morphology on the outermost silica shell can be controlled by simply adjusting the VTES-to-TEOS molar ratio (VTES: triethoxyvinylsilane, TEOS: tetraethyl orthosilicate) as well as the etching time. The as-synthesized products exhibit fluorescence performance by incorporating rhodamine B isothiocyanate (RITC) covalently into the inner silica walls, which provide potential application in bioimaging. We also demonstrate the applications of as-synthesized large-pore structured nanocomposites in drug delivery systems and stimuli-responsive nanoreactors for heterogeneous catalysis.The core-shell structured mesoporous silica nanomaterials (MSNs) are experiencing rapid development in many applications such as heterogeneous catalysis, bio-imaging and drug delivery wherein a large pore volume is desirable. We develop a one-pot method for large-scale synthesis of brain-like mesoporous silica nanocomposites based on the reasonable change of the intrinsic nature of the -Si-O-Si- framework of silica nanoparticles together with a selective etching strategy. The as-synthesized products show good monodispersion and a large pore volume of 1.0 cm3 g-1. The novelty of this approach lies in the use of an inorganic-organic hybrid layer to assist the creation of large-pore morphology on the outermost shell thereby promoting efficient mass transfer or storage. Importantly, the method is reliable and grams of products can be easily prepared. The morphology on the outermost silica shell can be controlled by simply adjusting the VTES-to-TEOS molar ratio (VTES: triethoxyvinylsilane, TEOS: tetraethyl orthosilicate) as well as the etching time. The as-synthesized products exhibit fluorescence performance by incorporating rhodamine B isothiocyanate (RITC) covalently into the inner silica walls, which provide potential application in bioimaging. We also demonstrate the applications of as-synthesized large-pore structured nanocomposites in drug delivery systems and stimuli-responsive nanoreactors for heterogeneous catalysis. Electronic supplementary information (ESI) available: The average particle size distribution of LPASN-1, LPASN-2 and LPASN-3; the wide-angle XRD pattern of LPASN-2/LPASN-3/LPASN-4; the catalytic properties of LPASN-PNIPAM at different temperatures (15 °C and 33 °C). See DOI: 10.1039/c5nr04123f
Synthesis of oligonucleotides on a soluble support
2017-01-01
Oligonucleotides are usually prepared in lab scale on a solid support with the aid of a fully automated synthesizer. Scaling up of the equipment has allowed industrial synthesis up to kilogram scale. In spite of this, solution-phase synthesis has received continuous interest, on one hand as a technique that could enable synthesis of even larger amounts and, on the other hand, as a gram scale laboratory synthesis without any special equipment. The synthesis on a soluble support has been regarded as an approach that could combine the advantageous features of both the solution and solid-phase syntheses. The critical step of this approach is the separation of the support-anchored oligonucleotide chain from the monomeric building block and other small molecular reagents and byproducts after each coupling, oxidation and deprotection step. The techniques applied so far include precipitation, extraction, chromatography and nanofiltration. As regards coupling, all conventional chemistries, viz. phosphoramidite, H-phosphonate and phosphotriester strategies, have been attempted. While P(III)-based phosphoramidite and H-phosphonate chemistries are almost exclusively used on a solid support, the “outdated” P(V)-based phosphotriester chemistry still offers one major advantage for the synthesis on a soluble support; the omission of the oxidation step simplifies the coupling cycle. Several of protocols developed for the soluble-supported synthesis allow the preparation of both DNA and RNA oligomers of limited length in gram scale without any special equipment, being evidently of interest for research groups that need oligonucleotides in large amounts for research purposes. However, none of them has really tested at such a scale that the feasibility of their industrial use could be critically judged. PMID:28781703
Ko, K Y; Ahn, D U
2007-02-01
The objective of this study was to develop an economical, simple, and large-scale separation method for IgY from egg yolk. Egg yolk diluted with 9 volumes of cold water was centrifuged after adjusting the pH to 5.0. The supernatant was added with 0.01% charcoal or 0.01% carrageenan and centrifuged at 2,800 x g for 30 min. The supernatant was filtered through a Whatman no. 1 filter paper and then the filtrate was concentrated to 20% original volume using ultrafiltration. The concentrated solution was further purified using either cation exchange chromatography or ammonium sulfate precipitation. For the cation exchange chromatography method, the concentrated sample was loaded onto a column equilibrated with 20 mM citrate-phosphate buffer at pH 4.8 and eluted with 200 mM citrate-phosphate buffer at pH 6.4. For the ammonium sulfate precipitation method, the concentrated sample was twice precipitated with 40% ammonium sulfate solution at pH 9.0. The yield and purity of IgY were determined by ELISA and electrophoresis. The yield of IgY from the cation exchange chromatography method was 30 to 40%, whereas that of the ammonium sulfate precipitation was 70 to 80%. The purity of IgY from the ammonium sulfate method was higher than that of the cation exchange chromatography. The cation exchange chromatography could handle only a small amount of samples, whereas the ammonium sulfate precipitation could handle a large volume of samples. This suggests that ammonium sulfate precipitation was a more efficient and useful purification method than cation exchange chromatography for the large-scale preparation of IgY from egg yolk.
NASA Astrophysics Data System (ADS)
Chang, Binbin; Zhang, Shouren; Yin, Hang; Yang, Baocheng
2017-08-01
Herein, considering the great potential of nitrogen-doped hierarchical porous carbons in energy storage and CO2 capture, we designed a convenient and easily large-scale production strategy for preparing nitrogen-doped hierarchical porous carbon sphere (NHPCS) materials. In this synthesis route, spherical resorcinol-formaldehyde (RF) resins were selected as carbon precursor, and then the ZnCl2-impregnated RF resin spheres were carbonized in a NH3 atmosphere at a temperature range of 600-800 °C. During the one-step heat-treatment process, nitrogen atom could be efficiently incorporated into the carbon skeleton, and the interconnected and hierarchical pore structure with different micro/mesopore proportion could be generated and tuned by adjusting the activating agent ZnCl2 dosage and carbonization temperature. The resultant nitrogen-doped hierarchical porous carbon sphere materials exhibited a satisfactory charge storage capacity, and the optimal sample of NHPCS-2-8 with a high mesopore proportion obtained at 800 °C with a ZnCl2/RF mass ratio of 2:1 presented a specific capacitance of 273.8 F g-1 at a current density of 0.5 A g-1. More importantly, the assembled NHPCS-2-8-based symmetric capacitor displayed a high energy density of 17.2 Wh kg-1 at a power density of 178.9 W kg-1 within a voltage window of 0 ∼ 1.8 V in 0.5 M Na2SO4 aqueous electrolyte. In addition, the CO2 capture application of these NHPCS materials was also explored, and the optimal sample of NHPCS-0-8 with a large micropore proportion prepared at 800 °C exhibited an exceptional CO2 uptake capacity at ambient pressures of up to 4.23 mmol g-1 at 0 °C.
Preparative free-flow electrophoresis as a method of fractionation of natural organic materials
Leenheer, J.A.; Malcolm, R.L.
1973-01-01
Preparative free-flow electrophoresis was found to be an efficient method of conducting large-scale fractionations of the natural organic polyelectrolytes occurring in many surface waters and soils. The method of free-flow electrophoresis obviates, the problem of adsorption upon a supporting medium and permits the use of high potential gradients and currents because of an efficient cooling system. Separations were monitored by determining organic carbon concentration with a dissolved carbon analyzer, and color was measured by absorbance at 400 nanometers. Organic materials from waters and soils were purified by filtration, hydrogen exchange, and dialysis and were concentrated by freeze drying or freeze concentration. In electrophoretic fractionations of natural organic materials typically found in surface waters and soils, color was found to increase with the charge of the fraction.
Ahmad, Muthanna; Grime, Geoffrey W
2013-04-01
Porous silicon (PS) has been prepared using a microwave-assisted hydrofluoric acid (HF) etching method from a silicon wafer pre-implanted with 5 MeV Cu ions. The use of microbeam proton-induced X-ray emission (micro-PIXE) and microbeam Rutherford backscattering techniques reveals for the first time the capability of these techniques for studying the formation of micropores. The porous structures observed from micro-PIXE imaging results are compared to scanning electron microscope images. It was observed that the implanted copper accumulates in the same location as the pores and that at high implanted dose the pores form large-scale patterns of lines and concentric circles. This is the first work demonstrating the use of microwave-assisted HF etching in the formation of PS.
Jang, Bora; Kim, Boyoung; Kim, Hyunsook; Kwon, Hyokyoung; Kim, Minjeong; Seo, Yunmi; Colas, Marion; Jeong, Hansaem; Jeong, Eun Hye; Lee, Kyuri; Lee, Hyukjin
2018-06-08
Enzymatic synthesis of RNA nanostructures is achieved by isothermal rolling circle transcription (RCT). Each arm of RNA nanostructures provides a functional role of Dicer substrate RNA inducing sequence specific RNA interference (RNAi). Three different RNAi sequences (GFP, RFP, and BFP) are incorporated within the three-arm junction RNA nanostructures (Y-RNA). The template and helper DNA strands are designed for the large-scale in vitro synthesis of RNA strands to prepare self-assembled Y-RNA. Interestingly, Dicer processing of Y-RNA is highly influenced by its physical structure and different gene silencing activity is achieved depending on its arm length and overhang. In addition, enzymatic synthesis allows the preparation of various Y-RNA structures using a single DNA template offering on demand regulation of multiple target genes.
Long-range exciton transport in conjugated polymer nanofibers prepared by seeded growth
NASA Astrophysics Data System (ADS)
Jin, Xu-Hui; Price, Michael B.; Finnegan, John R.; Boott, Charlotte E.; Richter, Johannes M.; Rao, Akshay; Menke, S. Matthew; Friend, Richard H.; Whittell, George R.; Manners, Ian
2018-05-01
Easily processed materials with the ability to transport excitons over length scales of more than 100 nanometers are highly desirable for a range of light-harvesting and optoelectronic devices. We describe the preparation of organic semiconducting nanofibers comprising a crystalline poly(di-n-hexylfluorene) core and a solvated, segmented corona consisting of polyethylene glycol in the center and polythiophene at the ends. These nanofibers exhibit exciton transfer from the core to the lower-energy polythiophene coronas in the end blocks, which occurs in the direction of the interchain π-π stacking with very long diffusion lengths (>200 nanometers) and a large diffusion coefficient (0.5 square centimeters per second). This is made possible by the uniform exciton energetic landscape created by the well-ordered, crystalline nanofiber core.
Bladergroen, Marco R.; van der Burgt, Yuri E. M.
2015-01-01
For large-scale and standardized applications in mass spectrometry- (MS-) based proteomics automation of each step is essential. Here we present high-throughput sample preparation solutions for balancing the speed of current MS-acquisitions and the time needed for analytical workup of body fluids. The discussed workflows reduce body fluid sample complexity and apply for both bottom-up proteomics experiments and top-down protein characterization approaches. Various sample preparation methods that involve solid-phase extraction (SPE) including affinity enrichment strategies have been automated. Obtained peptide and protein fractions can be mass analyzed by direct infusion into an electrospray ionization (ESI) source or by means of matrix-assisted laser desorption ionization (MALDI) without further need of time-consuming liquid chromatography (LC) separations. PMID:25692071
Wang, Deli; Xin, Huolin L; Yu, Yingchao; Wang, Hongsen; Rus, Eric; Muller, David A; Abruña, Hector D
2010-12-22
A simple method for the preparation of PdCo@Pd core-shell nanoparticles supported on carbon based on an adsorbate-induced surface segregation effect has been developed. The stability of these PdCo@Pd nanoparticles and their electrocatalytic activity for the oxygen reduction reaction (ORR) were enhanced by decoration with a small amount of Pt deposited via a spontaneous displacement reaction. The facile method described herein is suitable for large-scale, lower-cost production and significantly lowers the Pt loading and thus the cost. The as-prepared PdCo@Pd and Pd-decorated PdCo@Pd nanocatalysts have a higher methanol tolerance than Pt/C in the ORR and are promising cathode catalysts for fuel cell applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Deli; Xin, Huolin L.; Yu, Yingchao
2010-11-24
A simple method for the preparation of PdCo@Pd core-shell nanoparticles supported on carbon based on an adsorbate-induced surface segregation effect has been developed. The stability of these PdCo@Pd nanoparticles and their electrocatalytic activity for the oxygen reduction reaction (ORR) were enhanced by decoration with a small amount of Pt deposited via a spontaneous displacement reaction. The facile method described herein is suitable for large-scale, lower-cost production and significantly lowers the Pt loading and thus the cost. The as-prepared PdCo@Pd and Pd-decorated PdCo@Pd nanocatalysts have a higher methanol tolerance than Pt/C in the ORR and are promising cathode catalysts for fuelmore » cell applications.« less
Polar continental margins: Studies off East Greenland
NASA Astrophysics Data System (ADS)
Mienert, J.; Thiede, J.; Kenyon, N. H.; Hollender, F.-J.
The passive continental margin off east Greenland has been shaped by tectonic and sedimentary processes, and typical physiographic patterns have evolved over the past few million years under the influence of the late Cenozoic Northern Hemisphere glaciations. The Greenland ice shield has been particularly affected.GLORIA (Geological Long Range Inclined Asdic), the Institute of Oceanographic Sciences' (IOS) long-range, side-scan sonar, was used on a 1992 RV Livonia cruise to map large-scale changes in sedimentary patterns along the east Greenland continental margin. The overall objective of this research program was to determine the variety of large-scale seafloor processes to improve our understanding of the interaction between ice sheets, current regimes, and sedimentary processes. In cooperation with IOS and the RV Livonia, a high-quality set of seafloor data has been produced. GLORIA'S first survey of east Greenland's continental margin covered several 1000- × 50-km-wide swaths (Figure 1) and yielded an impressive sidescan sonar image of the complete Greenland Basin and margin (about 250,000 km2). A mosaic of the data was made at a scale of 1:375,000. The base map was prepared with a polar stereographic projection having a standard parallel of 71°.
Cable tunnel fire experiment study based on linear optical fiber fire detectors
NASA Astrophysics Data System (ADS)
Fan, Dian; Ding, Hongjun
2013-09-01
Aiming at exiting linear temperature fire detection technology including temperature sensing cable, fiber Raman scattering, fiber Bragg grating, this paper establish an experimental platform in cable tunnel, set two different experimental scenes of the fire and record temperature variation and fire detector response time in the processing of fire simulation. Since a small amount of thermal radiation and no flame for the beginning of the small-scale fire, only directly contacting heat detectors can make alarm response and the rest of other non- contact detectors are unable to respond. In large-scale fire, the alarm response time of the fiber Raman temperature sensing fire detector and fiber Bragg grating temperature sensing fire detector is about 30 seconds, and depending on the thermocouples' record the temperature over the fire is less than 35° in first 60 seconds of large-scale fire, while the temperature rising is more than 5°/min within the range of +/- 3m. According to the technical characteristics of the three detectors, the engineering suitability of the typical linear heat detectors in cable tunnels early fire detection is analyzed, which provide technical support for the preparation of norms.
Screening and large-scale expression of membrane proteins in mammalian cells for structural studies.
Goehring, April; Lee, Chia-Hsueh; Wang, Kevin H; Michel, Jennifer Carlisle; Claxton, Derek P; Baconguis, Isabelle; Althoff, Thorsten; Fischer, Suzanne; Garcia, K Christopher; Gouaux, Eric
2014-11-01
Structural, biochemical and biophysical studies of eukaryotic membrane proteins are often hampered by difficulties in overexpression of the candidate molecule. Baculovirus transduction of mammalian cells (BacMam), although a powerful method to heterologously express membrane proteins, can be cumbersome for screening and expression of multiple constructs. We therefore developed plasmid Eric Gouaux (pEG) BacMam, a vector optimized for use in screening assays, as well as for efficient production of baculovirus and robust expression of the target protein. In this protocol, we show how to use small-scale transient transfection and fluorescence-detection size-exclusion chromatography (FSEC) experiments using a GFP-His8-tagged candidate protein to screen for monodispersity and expression level. Once promising candidates are identified, we describe how to generate baculovirus, transduce HEK293S GnTI(-) (N-acetylglucosaminyltransferase I-negative) cells in suspension culture and overexpress the candidate protein. We have used these methods to prepare pure samples of chicken acid-sensing ion channel 1a (cASIC1) and Caenorhabditis elegans glutamate-gated chloride channel (GluCl) for X-ray crystallography, demonstrating how to rapidly and efficiently screen hundreds of constructs and accomplish large-scale expression in 4-6 weeks.
Screening and large-scale expression of membrane proteins in mammalian cells for structural studies
Goehring, April; Lee, Chia-Hsueh; Wang, Kevin H.; Michel, Jennifer Carlisle; Claxton, Derek P.; Baconguis, Isabelle; Althoff, Thorsten; Fischer, Suzanne; Garcia, K. Christopher; Gouaux, Eric
2014-01-01
Structural, biochemical and biophysical studies of eukaryotic membrane proteins are often hampered by difficulties in over-expression of the candidate molecule. Baculovirus transduction of mammalian cells (BacMam), although a powerful method to heterologously express membrane proteins, can be cumbersome for screening and expression of multiple constructs. We therefore developed plasmid Eric Gouaux (pEG) BacMam, a vector optimized for use in screening assays, as well as for efficient production of baculovirus and robust expression of the target protein. In this protocol we show how to use small-scale transient transfection and fluorescence-detection, size-exclusion chromatography (FSEC) experiments using a GFP-His8 tagged candidate protein to screen for monodispersity and expression level. Once promising candidates are identified, we describe how to generate baculovirus, transduce HEK293S GnTI− (N-acetylglucosaminyltransferase I-negative) cells in suspension culture, and over-express the candidate protein. We have used these methods to prepare pure samples of chicken acid-sensing ion channel 1a (cASIC1) and Caenorhabditis elegans glutamate-gated chloride channel (GluCl), for X-ray crystallography, demonstrating how to rapidly and efficiently screen hundreds of constructs and accomplish large-scale expression in 4-6 weeks. PMID:25299155
Inkjet-Spray Hybrid Printing for 3D Freeform Fabrication of Multilayered Hydrogel Structures.
Yoon, Sejeong; Park, Ju An; Lee, Hwa-Rim; Yoon, Woong Hee; Hwang, Dong Soo; Jung, Sungjune
2018-04-30
Here, a new bioprinting process by combining drop-on-demand inkjet printing with a spray-coating technique, which enables the high-resolution, high-speed, and freeform fabrication of large-scale cell-laden hydrogel structures is reported. Hydrogel structures with various shapes and composed of different materials, including alginate, cellulose nanofiber, and fibrinogen, are fabricated using the inkjet-spray printing. To manufacture cell-friendly hydrogel structures with controllable stiffness, gelatine methacryloyl is saponified to stabilize jet formation and is subsequently mixed with sodium alginate to prepare blend inks. The hydrogels crosslinked from the blend inks are characterized by assessing physical properties including the microstructure and mechanical stiffness and cellular responses including the cell viability, metabolic activity, and functionality of human dermal fibroblasts within the hydrogel. Cell-laden hydrogel structures are generated on a large scale and collagen type I secretion and spreading of cells within the hydrogels are assessed. The results demonstrate that the inkjet-spray printing system will ensure the formation of a cell-laden hydrogel structure with high shape fidelity in a rapid and reliable manner. Ultimately, the proposed printing technique and the blend bioink to be used to fabricate 3D laminated large-scale tissue equivalents that potentially mimic the function of native tissues is expected. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Aghebati Maleki, Leili; Majidi, Jafar; Baradaran, Behzad; Abdolalizadeh, Jalal; Kazemi, Tohid; Aghebati Maleki, Ali; Sineh sepehr, Koushan
2013-01-01
Purpose: Monoclonal antibodies or specific antibodies are now an essential tool of biomedical research and are of great commercial and medical value. The purpose of this study was to produce large scale of monoclonal antibody against CD34 in order to diagnostic application in leukemia and purification of human hematopoietic stem/progenitor cells. Methods: For large scale production of monoclonal antibody, hybridoma cells that produce monoclonal antibody against human CD34 were injected into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. 5 ml ascitic fluid was harvested from each mouse in two times. Evaluation of mAb titration was assessed by ELISA method. The ascitic fluid was examined for class and subclasses by ELISA mouse mAb isotyping Kit. mAb was purified from ascitic fluid by affinity chromatography on Protein A-Sepharose. Purity of monoclonal antibody was monitored by SDS -PAGE and the purified monoclonal antibody was conjugated with FITC. Results: Monoclonal antibodies with high specificity and sensitivity against human CD34 by hybridoma technology were prepared. The subclass of antibody was IgG1 and its light chain was kappa. Conclusion: The conjugated monoclonal antibody could be a useful tool for isolation, purification and characterization of human hematopoietic stem cells. PMID:24312838
Maritime transport in the Gulf of Bothnia 2030.
Pekkarinen, Annukka; Repka, Sari
2014-10-01
Scenarios for shipping traffic in the Gulf of Bothnia (GoB) by 2030 are described in order to identify the main factors that should be taken into account when preparing a Maritime Spatial Plan (MSP) for the area. The application of future research methodology to planning of marine areas was also assessed. The methods include applying existing large scale quantitative scenarios for maritime traffic in the GoB and using real-time Delphi in which an expert group discussed different factors contributing to future maritime traffic in the GoB to find out the probability and significance of the factors having an impact on maritime traffic. MSP was tested on transnational scale in the Bothnian sea area as a pilot project.
Large-area few-layer hexagonal boron nitride prepared by quadrupole field aided exfoliation
NASA Astrophysics Data System (ADS)
Lun Lu, Han; Zhi Rong, Min; Qiu Zhang, Ming
2018-03-01
A quadrupole electric field-mediated exfoliation method is proposed to convert micron-sized hexagonal boron nitride (h-BN) powder into few-layer hexagonal boron nitride nanosheets (h-BNNS). Under optimum conditions (400 Hz, 40 V, 32 μg ml-1, sodium deoxycholate, TAE medium), the h-BN powders (thickness >200 nm, horizontal scale ˜10 μm) are successfully exfoliated into 0.5-4 nm (1-10 layers) thick h-BNNS with the same horizontal scale. Dynamic laser scattering and atomic force microscope data show that the yield is 47.6% (for the portion with the thickness of 0.5-6 nm), and all of the vertical sizes are reduced to smaller than 18 nm (45 layers).
Jankowski, Stéphane; Currie-Fraser, Erica; Xu, Licen; Coffa, Jordy
2008-09-01
Annotated DNA samples that had been previously analyzed were tested using multiplex ligation-dependent probe amplification (MLPA) assays containing probes targeting BRCA1, BRCA2, and MMR (MLH1/MSH2 genes) and the 9p21 chromosomal region. MLPA polymerase chain reaction products were separated on a capillary electrophoresis platform, and the data were analyzed using GeneMapper v4.0 software (Applied Biosystems, Foster City, CA). After signal normalization, loci regions that had undergone deletions or duplications were identified using the GeneMapper Report Manager and verified using the DyeScale functionality. The results highlight an easy-to-use, optimal sample preparation and analysis workflow that can be used for both small- and large-scale studies.
Huang, Hongliang; Li, Jian-Rong; Wang, Keke; Han, Tongtong; Tong, Minman; Li, Liangsha; Xie, Yabo; Yang, Qingyuan; Liu, Dahuan; Zhong, Chongli
2015-01-01
Metal-organic frameworks (MOFs) have recently emerged as a new type of nanoporous materials with tailorable structures and functions. Usually, MOFs have uniform pores smaller than 2 nm in size, limiting their practical applications in some cases. Although a few approaches have been adopted to prepare MOFs with larger pores, it is still challenging to synthesize hierarchical-pore MOFs (H-MOFs) with high structural controllability and good stability. Here we demonstrate a facile and versatile method, an in situ self-assembly template strategy for fabricating stable H-MOFs, in which multi-scale soluble and/or acid-sensitive metal-organic assembly (MOA) fragments form during the reactions between metal ions and organic ligands (to construct MOFs), and act as removable dynamic chemical templates. This general strategy was successfully used to prepare various H-MOFs that show rich porous properties and potential applications, such as in large molecule adsorption. Notably, the mesopore sizes of the H-MOFs can be tuned by varying the amount of templates. PMID:26548441
NASA Astrophysics Data System (ADS)
Liu, Runru; Wen, Dongdong; Zhang, Xueyu; Wang, Dejun; Yang, Qiang; Yuan, Beilei; Lü, Wei
2018-06-01
In this work, three-Dimensional nitrogen-doped graphene/MnO2 (NG/MnO2) was prepared by plasma treatment, which provides a high specific surface area due to porous structure and exhibits enhanced supercapacitor performance. The advantage of NG/MnO2 electrode was obvious compared with reduced graphene oxide/MnO2 (RGO/MnO2) which was prepared by traditional hydrothermal method, such as improved electrochemical property and better cycling stability. The specific capacitance of NG/MnO2 at the scan rate of 5 mV s‑1 (393 F g‑1) is higher than that of RGO/MnO2 (260 F g‑1). In addition, NG/MnO2 showed higher durability with 90.2% capacitance retention than that of RGO/MnO2 (82%) after 5000 cycles. Such cheap and high-performance supercapacitor electrodes are available by our feasible plasma treatment, which give promise in large-scale commercial energy storage devices.
Superhydrophobic and transparent coatings prepared by self-assembly of dual-sized silica particles
NASA Astrophysics Data System (ADS)
Xu, Qian-Feng; Wang, Jian-Nong
2010-06-01
Superhydrophobic and transparent coatings have been prepared by self-assembly of dual-sized silica particles from a mixed dispersion. The desirable micro/nano hierarchical structure for superhydrophobicity is constructed simply by adjusting the size and ratio of the dual-sized particles without organic/inorganic templates. The transparency of the prepared coatings is also researched, and the light scattering can be reduced by lowering the ratio of big sub-micro particles while the superhydrophobicity maintains unchanged. When nano particles with a diameter of 50 nm and sub-micro particles with a diameter of 350 nm are assembled, a superhydrophobic property with a water contact angle of 161° is achieved. Additionally, the coated glass is also very transparent. The highest transmittance of the coated glass can reach 85%. Compared to traditional colloid self-assembly approach, which often involves dozens of steps of layer-by-layer processing and organic/inorganic templates, the present approach is much simpler and has advantages for large-scale coating.
Synthesis of water dispersible boron core silica shell (B@SiO2) nanoparticles
NASA Astrophysics Data System (ADS)
Walton, Nathan I.; Gao, Zhe; Eygeris, Yulia; Ghandehari, Hamidreza; Zharov, Ilya
2018-04-01
Water dispersible boron nanoparticles have great potential as materials for boron neutron capture therapy of cancer and magnetic resonance imaging, if they are prepared on a large scale with uniform size and shape and hydrophilic modifiable surface. We report the first method to prepare spherical, monodisperse, water dispersible boron core silica shell nanoparticles (B@SiO2 NPs) suitable for aforementioned biomedical applications. In this method, 40 nm elemental boron nanoparticles, easily prepared by mechanical milling and carrying 10-undecenoic acid surface ligands, are hydrosilylated using triethoxysilane, followed by base-catalyzed hydrolysis of tetraethoxysilane, which forms a 10-nm silica shell around the boron core. This simple two-step process converts irregularly shaped hydrophobic boron particles into the spherically shaped uniform nanoparticles. The B@SiO2 NPs are dispersible in water and the silica shell surface can be modified with primary amines that allow for the attachment of a fluorophore and, potentially, of targeting moieties. [Figure not available: see fulltext.
Edge-localized mode avoidance and pedestal structure in I-mode plasmas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Walk, J. R., E-mail: jrwalk@psfc.mit.edu; Hughes, J. W.; Hubbard, A. E.
I-mode is a high-performance tokamak regime characterized by the formation of a temperature pedestal and enhanced energy confinement, without an accompanying density pedestal or drop in particle and impurity transport. I-mode operation appears to have naturally occurring suppression of large Edge-Localized Modes (ELMs) in addition to its highly favorable scalings of pedestal structure and overall performance. Extensive study of the ELMy H-mode has led to the development of the EPED model, which utilizes calculations of coupled peeling-ballooning MHD modes and kinetic-ballooning mode (KBM) stability limits to predict the pedestal structure preceding an ELM crash. We apply similar tools to themore » structure and ELM stability of I-mode pedestals. Analysis of I-mode discharges prepared with high-resolution pedestal data from the most recent C-Mod campaign reveals favorable pedestal scalings for extrapolation to large machines—pedestal temperature scales strongly with power per particle P{sub net}/n{sup ¯}{sub e}, and likewise pedestal pressure scales as the net heating power (consistent with weak degradation of confinement with heating power). Matched discharges in current, field, and shaping demonstrate the decoupling of energy and particle transport in I-mode, increasing fueling to span nearly a factor of two in density while maintaining matched temperature pedestals with consistent levels of P{sub net}/n{sup ¯}{sub e}. This is consistent with targets for increased performance in I-mode, elevating pedestal β{sub p} and global performance with matched increases in density and heating power. MHD calculations using the ELITE code indicate that I-mode pedestals are strongly stable to edge peeling-ballooning instabilities. Likewise, numerical modeling of the KBM turbulence onset, as well as scalings of the pedestal width with poloidal beta, indicates that I-mode pedestals are not limited by KBM turbulence—both features identified with the trigger for large ELMs, consistent with the observed suppression of large ELMs in I-mode.« less
Edge-localized mode avoidance and pedestal structure in I-mode plasmasa)
NASA Astrophysics Data System (ADS)
Walk, J. R.; Hughes, J. W.; Hubbard, A. E.; Terry, J. L.; Whyte, D. G.; White, A. E.; Baek, S. G.; Reinke, M. L.; Theiler, C.; Churchill, R. M.; Rice, J. E.; Snyder, P. B.; Osborne, T.; Dominguez, A.; Cziegler, I.
2014-05-01
I-mode is a high-performance tokamak regime characterized by the formation of a temperature pedestal and enhanced energy confinement, without an accompanying density pedestal or drop in particle and impurity transport. I-mode operation appears to have naturally occurring suppression of large Edge-Localized Modes (ELMs) in addition to its highly favorable scalings of pedestal structure and overall performance. Extensive study of the ELMy H-mode has led to the development of the EPED model, which utilizes calculations of coupled peeling-ballooning MHD modes and kinetic-ballooning mode (KBM) stability limits to predict the pedestal structure preceding an ELM crash. We apply similar tools to the structure and ELM stability of I-mode pedestals. Analysis of I-mode discharges prepared with high-resolution pedestal data from the most recent C-Mod campaign reveals favorable pedestal scalings for extrapolation to large machines—pedestal temperature scales strongly with power per particle Pnet/n ¯e, and likewise pedestal pressure scales as the net heating power (consistent with weak degradation of confinement with heating power). Matched discharges in current, field, and shaping demonstrate the decoupling of energy and particle transport in I-mode, increasing fueling to span nearly a factor of two in density while maintaining matched temperature pedestals with consistent levels of Pnet/n ¯e. This is consistent with targets for increased performance in I-mode, elevating pedestal βp and global performance with matched increases in density and heating power. MHD calculations using the ELITE code indicate that I-mode pedestals are strongly stable to edge peeling-ballooning instabilities. Likewise, numerical modeling of the KBM turbulence onset, as well as scalings of the pedestal width with poloidal beta, indicates that I-mode pedestals are not limited by KBM turbulence—both features identified with the trigger for large ELMs, consistent with the observed suppression of large ELMs in I-mode.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, Weishi; Shen, Jianfeng; Wan, Lei
2012-11-15
Graphical abstract: Well-shaped Y{sub 2}O{sub 3}:Yb/Er nanotubes have been successfully synthesized on a large scale via layer-by-layer assembly on carbon nanotubes templates followed by a subsequent heat treatment process. The as-prepared Y{sub 2}O{sub 3}:Yb/Er nanotubes show a strong red emission corresponding to the {sup 4}F{sub 9/2}–{sup 4}I{sub 15/2} transition of the Er{sup 3+} ions under excitation at 980 nm. Display Omitted Highlights: ► Well-shaped Y{sub 2}O{sub 3}:Yb/Er nanotubes have been successfully synthesized. ► CNTs were used as templates for Y{sub 2}O{sub 3}:Yb/Er nanotubes. ► LBL assembly and calcination were used for preparation of Y{sub 2}O{sub 3}:Yb/Er nanotubes. ► The as-preparedmore » Y{sub 2}O{sub 3}:Yb/Er nanotubes show a strong red emission. -- Abstract: Well-shaped Y{sub 2}O{sub 3}:Yb/Er nanotubes have been successfully synthesized on a large scale via layer-by-layer (LBL) assembly on carbon nanotubes (CNTs) templates followed by a subsequent heat treatment process. The crystal structure, element analysis, morphology and upconversion luminescence properties were characterized. XRD results demonstrate that the diffraction peaks of the samples calcinated at 800 °C or above can be indexed to the pure cubic phase of Y{sub 2}O{sub 3}. SEM images indicate that a large quantity of uniform and rough nanotubes with diameters of about 30–60 nm can be observed. The as-prepared Y{sub 2}O{sub 3}:Yb/Er nanotubes show a strong red emission corresponding to the {sup 4}F{sub 9/2}–{sup 4}I{sub 15/2} transition of the Er{sup 3+} ions under excitation at 980 nm, which have potential applications in such fields as nanoscale devices, molecular catalysts, nanobiotechnology, photonics and optoelectronics.« less
Men, Dandan; Wu, Yingyi; Wang, Chu; Xiang, Junhuai; Yang, Ganlan; Wan, Changjun; Zhang, Honghua
2018-02-04
Two-dimensional (2D) periodic micro/nanostructured arrays as SERS substrates have attracted intense attention due to their excellent uniformity and good stability. In this work, periodic hierarchical SiO₂ nanopillar arrays decorated with Ag nanoparticles (NPs) with clean surface were prepared on a wafer-scale using monolayer Au NP arrays as masks, followed by reactive ion etching (RIE), depositing Ag layer and annealing. For the prepared SiO₂ nanopillar arrays decorated with Ag NPs, the size of Ag NPs was tuned from ca. 24 to 126 nanometers by controlling the deposition thickness of Ag film. Importantly, the SiO₂ nanopillar arrays decorated with Ag NPs could be used as highly sensitive SERS substrate for the detection of 4-aminothiophenol (4-ATP) and rhodamine 6G (R6G) due to the high loading of Ag NPs and a very uniform morphology. With a deposition thickness of Ag layer of 30 nm, the SiO₂ nanopillar arrays decorated with Ag NPs exhibited the best sensitive SERS activity. The excellent SERS performance of this substrate is mainly attributed to high-density "hotspots" derived from nanogaps between Ag NPs. Furthermore, this strategy might be extended to synthesize other nanostructured arrays with a large area, which are difficult to be prepared only via conventional wet-chemical or physical methods.
López, Rosario Lucas; García, Ma Teresa; Abriouel, Hikmate; Ben Omar, Nabil; Grande, Ma José; Martínez-Cañamero, Magdalena; Gálvez, Antonio
2007-12-01
The influence of substrate composition on the production of enterocin EJ97 and the conditions for semi-preparative bacteriocin recovery have been studied. Final bacteriocin concentrations of 12.5 or 15.6 mg/l were obtained in the commercial media brain heart infusion broth (BHI) and tryptic soya broth, respectively. The bacteriocin was also produced in the complex medium CM (8.75 mg/l), in which the vitamin supplement was essential for production. Some combinations of meat peptone and yeast extract plus either soy peptone or BHI also supported bacteriocin production, at concentrations of 6.25-7.5 mg/l. In cow milk (whole, half-skimmed, and skimmed), the final bacteriocin concentrations obtained ranged from 7.5 to 11.25 mg/l. Highest bacteriocin activity was obtained by using pasteurised milk whey as growth substrate (up to 25 mg/l), suggesting that this bacteriocin can be obtained on a large scale by using this cheap food-grade industrial by-product. Highest bacteriocin titres were always obtained after 8 h of incubation at 37 degrees C. Semi-preparative concentration and purification of enterocin EJ97 produced in a complex medium was achieved by bulk cation exchange chromatography without previous cell separation, followed by reversed-phase chromatography. This two-step procedure allowed preparation of milligram quantities of purified bacteriocin, which is an improvement compared to purification procedures established for most other bacteriocins (35). The availability of purified enterocin EJ97 will facilitate other studies such as the elucidation of its molecular structure and its interaction with target bacteria.
Moreno, Rosa L.; Josey, Megan; Ribera, Angeles B.
2017-01-01
Zebrafish, first introduced as a developmental model, have gained popularity in many other fields. The ease of rearing large numbers of rapidly developing organisms, combined with the embryonic optical clarity, served as initial compelling attributes of this model. Over the past two decades, the success of this model has been further propelled by its amenability to large-scale mutagenesis screens and by the ease of transgenesis. More recently, gene-editing approaches have extended the power of the model. For neurodevelopmental studies, the zebrafish embryo and larva provide a model to which multiple methods can be applied. Here, we focus on methods that allow the study of an essential property of neurons, electrical excitability. Our preparation for the electrophysiological study of zebrafish spinal neurons involves the use of veterinarian suture glue to secure the preparation to a recording chamber. Alternative methods for recording from zebrafish embryos and larvae involve the attachment of the preparation to the chamber using a fine tungsten pin12345. A tungsten pin is most often used to mount the preparation in a lateral orientation, although it has been used to mount larvae dorsal-side up4. The suture glue has been used to mount embryos and larvae in both orientations. Using the glue, a minimal dissection can be performed, allowing access to spinal neurons without the use of an enzymatic treatment, thereby avoiding any resultant damage. However, for larvae, it is necessary to apply a brief enzyme treatment to remove the muscle tissue surrounding the spinal cord. The methods described here have been used to study the intrinsic electrical properties of motor neurons, interneurons, and sensory neurons at several developmental stages6789. PMID:28448016
Moreno, Rosa L; Josey, Megan; Ribera, Angeles B
2017-04-18
Zebrafish, first introduced as a developmental model, have gained popularity in many other fields. The ease of rearing large numbers of rapidly developing organisms, combined with the embryonic optical clarity, served as initial compelling attributes of this model. Over the past two decades, the success of this model has been further propelled by its amenability to large-scale mutagenesis screens and by the ease of transgenesis. More recently, gene-editing approaches have extended the power of the model. For neurodevelopmental studies, the zebrafish embryo and larva provide a model to which multiple methods can be applied. Here, we focus on methods that allow the study of an essential property of neurons, electrical excitability. Our preparation for the electrophysiological study of zebrafish spinal neurons involves the use of veterinarian suture glue to secure the preparation to a recording chamber. Alternative methods for recording from zebrafish embryos and larvae involve the attachment of the preparation to the chamber using a fine tungsten pin 1 , 2 , 3 , 4 , 5 . A tungsten pin is most often used to mount the preparation in a lateral orientation, although it has been used to mount larvae dorsal-side up 4 . The suture glue has been used to mount embryos and larvae in both orientations. Using the glue, a minimal dissection can be performed, allowing access to spinal neurons without the use of an enzymatic treatment, thereby avoiding any resultant damage. However, for larvae, it is necessary to apply a brief enzyme treatment to remove the muscle tissue surrounding the spinal cord. The methods described here have been used to study the intrinsic electrical properties of motor neurons, interneurons, and sensory neurons at several developmental stages 6 , 7 , 8 , 9 .
Large Scale Analyses and Visualization of Adaptive Amino Acid Changes Projects.
Vázquez, Noé; Vieira, Cristina P; Amorim, Bárbara S R; Torres, André; López-Fernández, Hugo; Fdez-Riverola, Florentino; Sousa, José L R; Reboiro-Jato, Miguel; Vieira, Jorge
2018-03-01
When changes at few amino acid sites are the target of selection, adaptive amino acid changes in protein sequences can be identified using maximum-likelihood methods based on models of codon substitution (such as codeml). Although such methods have been employed numerous times using a variety of different organisms, the time needed to collect the data and prepare the input files means that tens or hundreds of coding regions are usually analyzed. Nevertheless, the recent availability of flexible and easy to use computer applications that collect relevant data (such as BDBM) and infer positively selected amino acid sites (such as ADOPS), means that the entire process is easier and quicker than before. However, the lack of a batch option in ADOPS, here reported, still precludes the analysis of hundreds or thousands of sequence files. Given the interest and possibility of running such large-scale projects, we have also developed a database where ADOPS projects can be stored. Therefore, this study also presents the B+ database, which is both a data repository and a convenient interface that looks at the information contained in ADOPS projects without the need to download and unzip the corresponding ADOPS project file. The ADOPS projects available at B+ can also be downloaded, unzipped, and opened using the ADOPS graphical interface. The availability of such a database ensures results repeatability, promotes data reuse with significant savings on the time needed for preparing datasets, and effortlessly allows further exploration of the data contained in ADOPS projects.
Covalent modification and exfoliation of graphene oxide using ferrocene
NASA Astrophysics Data System (ADS)
Avinash, M. B.; Subrahmanyam, K. S.; Sundarayya, Y.; Govindaraju, T.
2010-09-01
Large scale preparation of single-layer graphene and graphene oxide is of great importance due to their potential applications. We report a simple room temperature method for the exfoliation of graphene oxide using covalent modification of graphene oxide with ferrocene to obtain single-layer graphene oxide sheets. The samples were characterized by FESEM, HRTEM, AFM, EDAX, FT-IR, Raman and Mössbauer spectroscopic studies. HRTEM micrograph of the covalently modified graphene oxide showed increased interlayer spacing of ~2.4 nm due to ferrocene intercalation. The presence of single-layer graphene oxide sheets were confirmed by AFM studies. The covalently modified ferrocene-graphene oxide composite showed interesting magnetic behavior.Large scale preparation of single-layer graphene and graphene oxide is of great importance due to their potential applications. We report a simple room temperature method for the exfoliation of graphene oxide using covalent modification of graphene oxide with ferrocene to obtain single-layer graphene oxide sheets. The samples were characterized by FESEM, HRTEM, AFM, EDAX, FT-IR, Raman and Mössbauer spectroscopic studies. HRTEM micrograph of the covalently modified graphene oxide showed increased interlayer spacing of ~2.4 nm due to ferrocene intercalation. The presence of single-layer graphene oxide sheets were confirmed by AFM studies. The covalently modified ferrocene-graphene oxide composite showed interesting magnetic behavior. Electronic supplementary information (ESI) available: Magnetic data; AFM images; TEM micrographs; and Mössbauer spectroscopic data. See DOI: 10.1039/c0nr00024h
Yu, Jiaguo; Qi, Lifang
2009-09-30
Hierarchically flower-like tungsten trioxide assemblies were fabricated on a large scale by a simple hydrothermal treatment of sodium tungstate in aqueous solution of nitric acid. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy and N(2) adsorption-desorption measurements. The photocatalytic activity was evaluated by photocatalytic decolorization of rhodamine B aqueous solution under visible-light irradiation. It was found that the three-dimensional tungsten trioxide assemblies were constructed from two-dimensional layers, which were further composed of a large number of interconnected lathy nanoplates with different sizes. Such flower-like assemblies exhibited hierarchically porous structure and higher visible-light photocatalytic activity than the samples without such hierarchical structures due to their specific hierarchical pores that served as the transport paths for light and reactants. After five recycles for the photodegradation of RhB, the catalyst did not exhibit any great loss in activity, confirming hierarchically flower-like tungsten trioxide was stability and not photocorroded. This study may provide new insight into environmentally benign preparation and design of novel photocatalytic materials and enhancement of photocatalytic activity.
ERIC Educational Resources Information Center
Avan, Cagri; Aydinli, Bahattin; Bakar, Fatma; Alboga, Yunus
2011-01-01
The aim of this study is to introduce an attitude scale in order to define students? attitudes about environment, recycling, plastics, plastic waste. In this study, 80 attitude sentences according to 5-point Likert-type scale were prepared and applied to 492 students of 6th grade in the Kastamonu city center of Turkey. The scale consists of…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spagliardi, Fabio
Liquid argon Time Projection Chambers (LArTPCs) are becoming widely used as neutrino detectors because of their image-like event reconstruction which enables precision neutrino measurements. They primarily use ionisation charge to reconstruct neutrino events. It has been shown, however, that the scintillation light emitted by liquid argon could be exploited to improve their performance. As the neutrino measurements planned in the near future require large-scale experiments, their construction presents challenges in terms of both charge and light collection. In this dissertation we present solutions developed to improve the performance in both aspects of these detectors. We present a new wire tensioningmore » measurement method that allows a remote measurement of the tension of the large number wires that constitute the TPC anode. We also discuss the development and installation of WLS-compound covered foils for the SBND neutrino detector at Fermilab, which is a technique proposed t o augment light collection in LArTPCs. This included preparing a SBND-like mesh cathode and testing it in the Run III of LArIAT, a test beam detector also located at Fermilab. Finally, we present a study aimed at understanding late scintillation light emitted by recombining positive argon ions using LArIAT data, which could affect large scale surface detectors.« less
The TeraShake Computational Platform for Large-Scale Earthquake Simulations
NASA Astrophysics Data System (ADS)
Cui, Yifeng; Olsen, Kim; Chourasia, Amit; Moore, Reagan; Maechling, Philip; Jordan, Thomas
Geoscientific and computer science researchers with the Southern California Earthquake Center (SCEC) are conducting a large-scale, physics-based, computationally demanding earthquake system science research program with the goal of developing predictive models of earthquake processes. The computational demands of this program continue to increase rapidly as these researchers seek to perform physics-based numerical simulations of earthquake processes for larger meet the needs of this research program, a multiple-institution team coordinated by SCEC has integrated several scientific codes into a numerical modeling-based research tool we call the TeraShake computational platform (TSCP). A central component in the TSCP is a highly scalable earthquake wave propagation simulation program called the TeraShake anelastic wave propagation (TS-AWP) code. In this chapter, we describe how we extended an existing, stand-alone, wellvalidated, finite-difference, anelastic wave propagation modeling code into the highly scalable and widely used TS-AWP and then integrated this code into the TeraShake computational platform that provides end-to-end (initialization to analysis) research capabilities. We also describe the techniques used to enhance the TS-AWP parallel performance on TeraGrid supercomputers, as well as the TeraShake simulations phases including input preparation, run time, data archive management, and visualization. As a result of our efforts to improve its parallel efficiency, the TS-AWP has now shown highly efficient strong scaling on over 40K processors on IBM’s BlueGene/L Watson computer. In addition, the TSCP has developed into a computational system that is useful to many members of the SCEC community for performing large-scale earthquake simulations.
NASA Astrophysics Data System (ADS)
Perea, D. E.; Evans, J. E.
2017-12-01
The ability to image biointerfaces over nanometer to micrometer length scales is fundamental to correlating biological composition and structure to physiological function, and is aided by a multimodal approach using advanced complementary microscopic and spectroscopic characterization techniques. Atom Probe Tomography (APT) is a rapidly expanding technique for atomic-scale three-dimensional structural and chemical analysis. However, the regular application of APT to soft biological materials is lacking in large part due to difficulties in specimen preparation and inabilities to yield meaningful tomographic reconstructions that produce atomic scale compositional distributions as no other technique currently can. Here we describe the atomic-scale tomographic analysis of biological materials using APT that is facilitated by an advanced focused ion beam based approach. A novel specimen preparation strategy is used in the analysis of horse spleen ferritin protein embedded in an organic polymer resin which provides chemical contrast to distinguish the inorganic-organic interface of the ferrihydrite mineral core and protein shell of the ferritin protein. One-dimensional composition profiles directly reveal an enhanced concentration of P and Na at the surface of the ferrihydrite mineral core. We will also describe the development of a unique multifunctional environmental transfer hub allowing controlled cryogenic transfer of specimens under vacuum pressure conditions between an Atom Probe and cryo-FIB/SEM. The utility of the environmental transfer hub is demonstrated through the acquisition of previously unavailable mass spectral analysis of an intact organometallic molecule made possible via controlled cryogenic transfer. The results demonstrate a viable application of APT analysis to study complex biological organic/inorganic interfaces relevant to energy and the environment. References D.E. Perea et al. An environmental transfer hub for multimodal atom probe tomography, Adv. Struct. Chem. Imag, 2017, 3:12 The research was performed at the Environmental Molecular Sciences Laboratory; a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research located at Pacific Northwest National Laboratory.
Tran, Thi Ha; Nguyen, Viet Tuyen
2014-01-01
Cupric oxide (CuO), having a narrow bandgap of 1.2 eV and a variety of chemophysical properties, is recently attractive in many fields such as energy conversion, optoelectronic devices, and catalyst. Compared with bulk material, the advanced properties of CuO nanostructures have been demonstrated; however, the fact that these materials cannot yet be produced in large scale is an obstacle to realize the potential applications of this material. In this respect, chemical methods seem to be efficient synthesis processes which yield not only large quantities but also high quality and advanced material properties. In this paper, the effect of some general factors on the morphology and properties of CuO nanomaterials prepared by solution methods will be overviewed. In terms of advanced nanostructure synthesis, microwave method in which copper hydroxide nanostructures are produced in the precursor solution and sequentially transformed by microwave into CuO may be considered as a promising method to explore in the near future. This method produces not only large quantities of nanoproducts in a short reaction time of several minutes, but also high quality materials with advanced properties. A brief review on some unique properties and applications of CuO nanostructures will be also presented. PMID:27437488
Hudson, Judith N; Farmer, Elizabeth A; Weston, Kathryn M; Bushnell, John A
2015-01-16
Particularly when undertaken on a large scale, implementing innovation in higher education poses many challenges. Sustaining the innovation requires early adoption of a coherent implementation strategy. Using an example from clinical education, this article describes a process used to implement a large-scale innovation with the intent of achieving sustainability. Desire to improve the effectiveness of undergraduate medical education has led to growing support for a longitudinal integrated clerkship (LIC) model. This involves a move away from the traditional clerkship of 'block rotations' with frequent changes in disciplines, to a focus upon clerkships with longer duration and opportunity for students to build sustained relationships with supervisors, mentors, colleagues and patients. A growing number of medical schools have adopted the LIC model for a small percentage of their students. At a time when increasing medical school numbers and class sizes are leading to competition for clinical supervisors it is however a daunting challenge to provide a longitudinal clerkship for an entire medical school class. This challenge is presented to illustrate the strategy used to implement sustainable large scale innovation. A strategy to implement and build a sustainable longitudinal integrated community-based clerkship experience for all students was derived from a framework arising from Roberto and Levesque's research in business. The framework's four core processes: chartering, learning, mobilising and realigning, provided guidance in preparing and rolling out the 'whole of class' innovation. Roberto and Levesque's framework proved useful for identifying the foundations of the implementation strategy, with special emphasis on the relationship building required to implement such an ambitious initiative. Although this was innovation in a new School it required change within the school, wider university and health community. Challenges encountered included some resistance to moving away from traditional hospital-centred education, initial student concern, resource limitations, workforce shortage and potential burnout of the innovators. Large-scale innovations in medical education may productively draw upon research from other disciplines for guidance on how to lay the foundations for successfully achieving sustainability.
Namai, Yoshimichi; Matsuoka, Osamu
2006-04-06
We succeeded in observing the atomic scale structure of a rutile-type TiO2(110) single-crystal surface prepared by the wet chemical method of chemical etching in an acid solution and surface annealing in air. Ultrahigh vacuum noncontact atomic force microscopy (UHV-NC-AFM) was used for observing the atomic scale structures of the surface. The UHV-NC-AFM measurements at 450 K, which is above a desorption temperature of molecularly adsorbed water on the TiO2(110) surface, enabled us to observe the atomic scale structure of the TiO2(110) surface prepared by the wet chemical method. In the UHV-NC-AFM measurements at room temperature (RT), however, the atomic scale structure of the TiO2(110) surface was not observed. The TiO2(110) surface may be covered with molecularly adsorbed water after the surface was prepared by the wet chemical method. The structure of the TiO2(110) surface that was prepared by the wet chemical method was consistent with the (1 x 1) bulk-terminated model of the TiO2(110) surface.
Katz, Philip O; Rex, Douglas K; Epstein, Michael; Grandhi, Nav K; Vanner, Stephen; Hookey, Lawrence C; Alderfer, Vivian; Joseph, Raymond E
2013-03-01
Optimal bowel preparation is vital for the efficacy and safety of colonoscopy. The inconvenience, discomfort, required consumption of large volumes of product, and potential adverse effects associated with some bowel preparations deter patients from colonoscopy and may provide inadequate cleansing. A dual-action, non-phosphate, natural orange-flavored, low-volume preparation containing sodium picosulfate and magnesium citrate (P/MC) is currently being reviewed for bowel cleansing. This was a phase 3, randomized, multicenter, assessor-blinded, prespecified non-inferiority, head-to-head study to investigate the efficacy, safety, and tolerability of day-before administration of P/MC vs. 2L polyethylene glycol solution and two 5-mg bisacodyl tablets (2L PEG-3350 and bisacodyl tablets (HalfLytely and Bisacodyl Tablets Bowel Prep Kit)) in adult patients preparing for colonoscopy (SEE CLEAR II Study). The primary objective of the study was to demonstrate the non-inferiority of P/MC to 2L PEG-3350 and bisacodyl tablets in overall colon cleansing using a modified Aronchick scale. In addition, efficacy in the ascending, mid (transverse and descending), and recto-sigmoid segments of colon was evaluated using a modified Ottawa scale. Patient acceptability and tolerability of the bowel preparations were assessed via a standard questionnaire. Safety was assessed based on the monitoring of adverse events (AEs) and meaningful findings on clinical evaluations including physical examinations, vital sign measurements, and electrocardiograms (ECGs). A total of 603 patients were randomized to receive either P/MC (n = 300) or 2L PEG-3350 and bisacodyl tablets (n = 303). Based on the Aronchick scale, successful overall cleansing was similar in patients receiving P/MC (83.0%) and patients receiving 2L PEG-3350 and bisacodyl tablets (79.7%). P/MC demonstrated non-inferiority to 2L PEG-3350 and bisacodyl tablets in overall cleansing of the colon, as measured by the Aronchick scale. Similarly, the efficacy of P/MC, as measured by the Ottawa scale, was non-inferior to 2L PEG-3350 and bisacodyl tablets in cleansing the ascending, mid, and recto-sigmoid segments of the colon. Patient-reported acceptability and tolerability for each item examined on the questionnaire was significantly greater for P/MC compared with 2L PEG-3350 and bisacodyl tablets (P<0.0001).Treatment-emergent AEs related to the bowel preparation reported by 1% of patients receiving P/MC or 2L PEG-3350 and bisacodyl tablets were nausea (3.0% vs. 4.3%), vomiting (1.4% vs. 2.0%), and headache (2.7% vs. 1.7%). No clinically meaningful changes were noted in either treatment arm in data collected from physical examinations, vital sign measurements, and ECGs. When administered as a day-before dose, the bowel cleansing effects of P/MC were non-inferior compared with 2L PEG-3350 and bisacodyl tablets using the clinician-rated Aronchick and Ottawa scales. Treatment acceptability was significantly more favorable in patients receiving P/MC than in patients receiving 2L PEG-3350 and bisacodyl tablets.
Schevernels, Hanne; Krebs, Ruth M.; Santens, Patrick; Woldorff, Marty G.; Boehler, C. Nico
2013-01-01
Recently, attempts have been made to disentangle the neural underpinnings of preparatory processes related to reward and attention. Functional magnetic resonance imaging (fMRI) research showed that neural activity related to the anticipation of reward and to attentional demands invokes neural activity patterns featuring large-scale overlap, along with some differences and interactions. Due to the limited temporal resolution of fMRI, however, the temporal dynamics of these processes remain unclear. Here, we report an event-related potentials (ERP) study in which cued attentional demands and reward prospect were combined in a factorial design. Results showed that reward prediction dominated early cue processing, as well as the early and later parts of the contingent negative variation (CNV) slow-wave ERP component that has been associated with task-preparation processes. Moreover these reward-related electrophysiological effects correlated across participants with response-time speeding on reward-prospect trials. In contrast, cued attentional demands affected only the later part of the CNV, with the highest amplitudes following cues predicting high-difficulty potential-reward targets, thus suggesting maximal task preparation when the task requires it and entails reward prospect. Consequently, we suggest that task-preparation processes triggered by reward can arise earlier, and potentially more directly, than strategic top-down aspects of preparation based on attentional demands. PMID:24064071
Isolated hepatocytes--past, present and future.
Berry, M N; Grivell, A R; Grivell, M B; Phillips, J W
1997-07-01
The first technique for large-scale preparation of isolated hepatocytes was described in 1953 and involved perfusion of rat liver under pressure with a Ca(2+)-free solution containing a chelating agent. Various modifications of this technique were in use over the next ten years, until it was demonstrated that cells prepared in this manner were grossly damaged, losing most of their cytoplasmic enzymes during the preparative procedure. The successful preparation of intact isolated hepatocytes by collagenase-treatment of liver was achieved in 1967, and the widespread use of intact hepatocyte suspensions was accelerated by the development soon after of high-yield preparative techniques involving perfusion of the liver with a medium containing collagenase. The introduction of the isolated hepatocyte preparation has enabled experimental studies that otherwise would not be feasible. Important advances have been the use of cultured hepatocytes, frequently of human origin, for the investigation of the metabolism and toxicology of potential therapeutic agents. Success in this field has been achieved through the steady improvement in techniques for the maintenance in culture of differentiated hepatocytes, and in particular their cytochrome P450 complexes. Another area showing considerable promise is the employment of hepatocytes, generally from a porcine source, in temporary support systems for patients with acute liver failure. Our own studies have concentrated on the demonstration of long-range interactions between hepatocyte compartments which suggest that energy transfer between cell compartments can take place without ATP turnover.
Kennedy, Richard; Pankratz, V. Shane; Swanson, Eric; Watson, David; Golding, Hana; Poland, Gregory A.
2009-01-01
Because of the bioterrorism threat posed by agents such as variola virus, considerable time, resources, and effort have been devoted to biodefense preparation. One avenue of this research has been the development of rapid, sensitive, high-throughput assays to validate immune responses to poxviruses. Here we describe the adaptation of a β-galactosidase reporter-based vaccinia virus neutralization assay to large-scale use in a study that included over 1,000 subjects. We also describe the statistical methods involved in analyzing the large quantity of data generated. The assay and its associated methods should prove useful tools in monitoring immune responses to next-generation smallpox vaccines, studying poxvirus immunity, and evaluating therapeutic agents such as vaccinia virus immune globulin. PMID:19535540
Collective synthesis of natural products by means of organocascade catalysis
Jones, Spencer B.; Simmons, Bryon; Mastracchio, Anthony; MacMillan, David W. C.
2012-01-01
Organic chemists are now able to synthesize small quantities of almost any known natural product, given sufficient time, resources and effort. However, translation of the academic successes in total synthesis to the large-scale construction of complex natural products and the development of large collections of biologically relevant molecules present significant challenges to synthetic chemists. Here we show that the application of two nature-inspired techniques, namely organocascade catalysis and collective natural product synthesis, can facilitate the preparation of useful quantities of a range of structurally diverse natural products from a common molecular scaffold. The power of this concept has been demonstrated through the expedient, asymmetric total syntheses of six well-known alkaloid natural products: strychnine, aspidospermidine, vincadifformine, akuammicine, kopsanone and kopsinine. PMID:21753848
Parallel processing for pitch splitting decomposition
NASA Astrophysics Data System (ADS)
Barnes, Levi; Li, Yong; Wadkins, David; Biederman, Steve; Miloslavsky, Alex; Cork, Chris
2009-10-01
Decomposition of an input pattern in preparation for a double patterning process is an inherently global problem in which the influence of a local decomposition decision can be felt across an entire pattern. In spite of this, a large portion of the work can be massively distributed. Here, we discuss the advantages of geometric distribution for polygon operations with limited range of influence. Further, we have found that even the naturally global "coloring" step can, in large part, be handled in a geometrically local manner. In some practical cases, up to 70% of the work can be distributed geometrically. We also describe the methods for partitioning the problem into local pieces and present scaling data up to 100 CPUs. These techniques reduce DPT decomposition runtime by orders of magnitude.
NASA Astrophysics Data System (ADS)
Tripathi, Nagesh Kumar; Sathe, Manisha
2017-12-01
Large scale production of activated carbon is need of ongoing research due to its excellent adsorption capacity for removal of heavy metals from contaminated solutions. In the present study, polymeric precursor polystyrene beads [Brunauer Emmett Teller (BET) surface area, 46 m2/g; carbon content, 40.64%; crushing strength, 0.32 kg/sphere] were used to produce a new variant of activated carbon, Activated Carbon Spheres (ACS) in a pilot scale fluidized bed reactor. ACS were prepared by carbonization of polymeric precursor at 850 °C followed by activation of resultant material with steam. Prepared ACS were characterized using scanning electron microscope, CHNS analyzer, thermogravimetric analyzer, surface area analyzer and crushing strength tester. The produced ACS have 1009 m2/g BET surface area, 0.89 cm3/g total pore volume, 92.32% carbon content and 1.1 kg/sphere crushing strength with less than 1% of moisture and ash content. The ACS were also evaluated for its potential to remove hexavalent chromium [Cr(VI)] from contaminated solutions. The chromium removal is observed to be 99.1% at initial concentration 50 mg/l, pH 2, ACS dose 1 g/l, contact time 2 h, agitation 120 rpm and temperature 30 °C. Thus ACS can be used as an adsorbent material for the removal of Cr(VI) from contaminated solutions.
Global small-scale lunar cartography
NASA Technical Reports Server (NTRS)
Lipskiy, Y. N.; Pskovskiy, Y. P.; Rodionova, Z. F.; Shevchenko, V. V.; Chikmachev, V. I.; Volchkova, L. I.
1972-01-01
The primary sources information for compiling this map were the photographs of the visible hemisphere obtained by earth-based observatories, the Luna 3 and Zond 3 pictures, and a small number of Lunar Orbiter pictures. The primary content of the complete lunar map is the surface relief and its tonal characteristics. In preparing the map, particular attention was devoted to the variety of lunar relief forms. The color spectrum of the map was selected not only for the natural coloring of the lunar surface, but also with the objective of achieving maximum expressiveness. A lunar globe to scale 1:10 million was prepared along with the preparation of the map. The scale of the globe, half that of the map, led to some selection and generalization of the relief forms. The globe permits maintaining simultaneously geometric similarity of contours, exact proportions of areas, and identical scales in all directions. The globe was prepared in both the Latin and Russian languages.
Romm, H; Ainsbury, E; Bajinskis, A; Barnard, S; Barquinero, J F; Barrios, L; Beinke, C; Puig-Casanovas, R; Deperas-Kaminska, M; Gregoire, E; Oestreicher, U; Lindholm, C; Moquet, J; Rothkamm, K; Sommer, S; Thierens, H; Vral, A; Vandersickel, V; Wojcik, A
2014-05-01
In the case of a large scale radiation accident high throughput methods of biological dosimetry for population triage are needed to identify individuals requiring clinical treatment. The dicentric assay performed in web-based scoring mode may be a very suitable technique. Within the MULTIBIODOSE EU FP7 project a network is being established of 8 laboratories with expertise in dose estimations based on the dicentric assay. Here, the manual dicentric assay was tested in a web-based scoring mode. More than 23,000 high resolution images of metaphase spreads (only first mitosis) were captured by four laboratories and established as image galleries on the internet (cloud). The galleries included images of a complete dose effect curve (0-5.0 Gy) and three types of irradiation scenarios simulating acute whole body, partial body and protracted exposure. The blood samples had been irradiated in vitro with gamma rays at the University of Ghent, Belgium. Two laboratories provided image galleries from Fluorescence plus Giemsa stained slides (3 h colcemid) and the image galleries from the other two laboratories contained images from Giemsa stained preparations (24 h colcemid). Each of the 8 participating laboratories analysed 3 dose points of the dose effect curve (scoring 100 cells for each point) and 3 unknown dose points (50 cells) for each of the 3 simulated irradiation scenarios. At first all analyses were performed in a QuickScan Mode without scoring individual chromosomes, followed by conventional scoring (only complete cells, 46 centromeres). The calibration curves obtained using these two scoring methods were very similar, with no significant difference in the linear-quadratic curve coefficients. Analysis of variance showed a significant effect of dose on the yield of dicentrics, but no significant effect of the laboratories, different methods of slide preparation or different incubation times used for colcemid. The results obtained to date within the MULTIBIODOSE project by a network of 8 collaborating laboratories throughout Europe are very promising. The dicentric assay in the web based scoring mode as a high throughput scoring strategy is a useful application for biodosimetry in the case of a large scale radiation accident.
Li, Wenke; Wayne, Gregory S; Lallaman, John E; Chang, Sou-Jen; Wittenberger, Steven J
2006-02-17
Ketoester 1 is cyclized to give pyran-3,5-dione 2 in 78% yield using a parallel addition of ketoester 1 and base NaO(t)Bu in refluxing THF. Compared to the previously reported procedures, these optimized conditions have significantly increased the yield of this transformation and the quality of pyran 2 and prove to be suitable for large-scale preparation. An application of 2 to the synthesis of ABT-598, a potassium channel opener, is demonstrated.
[Advances in mass spectrometry-based approaches for neuropeptide analysis].
Ji, Qianyue; Ma, Min; Peng, Xin; Jia, Chenxi; Ji, Qianyue
2017-07-25
Neuropeptides are an important class of endogenous bioactive substances involved in the function of the nervous system, and connect the brain and other neural and peripheral organs. Mass spectrometry-based neuropeptidomics are designed to study neuropeptides in a large-scale manner and obtain important molecular information to further understand the mechanism of nervous system regulation and the pathogenesis of neurological diseases. This review summarizes the basic strategies for the study of neuropeptides using mass spectrometry, including sample preparation and processing, qualitative and quantitative methods, and mass spectrometry imagining.
Operational earthquake forecasting can enhance earthquake preparedness
Jordan, T.H.; Marzocchi, W.; Michael, A.J.; Gerstenberger, M.C.
2014-01-01
We cannot yet predict large earthquakes in the short term with much reliability and skill, but the strong clustering exhibited in seismic sequences tells us that earthquake probabilities are not constant in time; they generally rise and fall over periods of days to years in correlation with nearby seismic activity. Operational earthquake forecasting (OEF) is the dissemination of authoritative information about these time‐dependent probabilities to help communities prepare for potentially destructive earthquakes. The goal of OEF is to inform the decisions that people and organizations must continually make to mitigate seismic risk and prepare for potentially destructive earthquakes on time scales from days to decades. To fulfill this role, OEF must provide a complete description of the seismic hazard—ground‐motion exceedance probabilities as well as short‐term rupture probabilities—in concert with the long‐term forecasts of probabilistic seismic‐hazard analysis (PSHA).
NASA Astrophysics Data System (ADS)
Edwards, Jacob T.; Merchant, Rohan R.; McClymont, Kyle S.; Knouse, Kyle W.; Qin, Tian; Malins, Lara R.; Vokits, Benjamin; Shaw, Scott A.; Bao, Deng-Hui; Wei, Fu-Liang; Zhou, Ting; Eastgate, Martin D.; Baran, Phil S.
2017-04-01
Olefin chemistry, through pericyclic reactions, polymerizations, oxidations, or reductions, has an essential role in the manipulation of organic matter. Despite its importance, olefin synthesis still relies largely on chemistry introduced more than three decades ago, with metathesis being the most recent addition. Here we describe a simple method of accessing olefins with any substitution pattern or geometry from one of the most ubiquitous and variegated building blocks of chemistry: alkyl carboxylic acids. The activating principles used in amide-bond synthesis can therefore be used, with nickel- or iron-based catalysis, to extract carbon dioxide from a carboxylic acid and economically replace it with an organozinc-derived olefin on a molar scale. We prepare more than 60 olefins across a range of substrate classes, and the ability to simplify retrosynthetic analysis is exemplified with the preparation of 16 different natural products across 10 different families.
Wu, Yingpeng; Ma, Yanfeng; Wang, Yan; Huang, Lu; Li, Na; Zhang, Tengfei; Zhang, Yi; Wan, Xiangjian; Huang, Yi; Chen, Yongsheng
2013-02-01
Coal, which is abundant and has an incompact structure, is a good candidate to replace graphite as the raw material for the production of graphene. Here, a new solution phase technique for the preparation of graphene from coal has been developed. The precursor: graphene oxide got from coal was examined by atomic force microscopy, dynamic light scattering and X-ray diffraction, the results showed the GO was a small and single layer sheet. The graphene was examined by X-ray photoelectron spectroscopy, and Raman spectroscopy. Furthermore, graphene films have been prepared using direct solution process and the electrical conductivity and Hall effect have been studied. The results showed the conductivity of the films could reach as high as 2.5 x 10(5) Sm(-1) and exhibited an n-type behavior.
Wakahara, Takatsugu; Sathish, Marappan; Miyazawa, Kun'ichi; Hu, Chunping; Tateyama, Yoshitaka; Nemoto, Yoshihiro; Sasaki, Toshio; Ito, Osamu
2009-07-29
The supramolecular nanoarchitectures, C(60)/ferrocene nanosheets, were prepared by a simple liquid-liquid interfacial precipitation method and fully characterized by means of SEM, STEM, HRTEM, XRD, Raman and UV-vis-NIR spectra. The highly crystallized C(60)/ferrocene hexagonal nanosheets had a size of ca. 9 microm and the formulation C(60)(ferrocene)(2). A strong charge-transfer (CT) band between ferrocene and C(60) was observed at 782 nm, indicating the presence of donor-acceptor interaction in the nanosheets. Upon heating the nanosheets to 150 degrees C, the CT band disappeared due to the sublimation of ferrocene from the C(60)/ferrocene hybrid, and C(60) nanosheets with an fcc crystal structure and the same shape and size as the C(60)/ferrocene nanosheets were obtained.
Scheurell, K; Noack, J; König, R; Hegmann, J; Jahn, R; Hofmann, Th; Löbmann, P; Lintner, B; Garcia-Juan, P; Eicher, J; Kemnitz, E
2015-12-07
A synthesis route for the preparation of optically transparent magnesium fluoride sols using magnesium acetate tetrahydrate as precursor is described. The obtained magnesium fluoride sols are stable for several months and can be applied for antireflective coatings on glass substrates. Reaction parameters in the course of sol synthesis are described in detail. Thus, properties of the precursor materials play a crucial role in the formation of the desired magnesium fluoride nanoparticles, this is drying the precursor has to be performed under defined mild conditions, re-solvation of the dried precursor has to be avoided and addition of water to the final sol-system has to be controlled strictly. Important properties of the magnesium fluoride sols like viscosity, particle size distribution, and structural information are presented as well.
Fluorescent carbon nanoparticles from Citrus sinensis as efficient sorbents for pollutant dyes.
Adedokun, Oluwaseun; Roy, Anurag; Awodugba, Ayodeji O; Devi, P Sujatha
2017-02-01
Here, we report a simple, green and economic process for the synthesis of highly fluorescent carbon nanoparticles (CPs) through low-temperature carbonization of a fruit waste, Citrus sinensis peel. This approach allows the large-scale production of aqueous CPs dispersions without any additives and post-treatment processes. The as-prepared CPs were of small particle size, exhibited bright blue fluorescence under UV irradiation (λ max = 365 nm) with excellent colloidal stability in water. The chemical composition, structure and morphology of the as-prepared CPs were analyzed using various spectroscopic techniques such as X-ray diffraction, transmission electron microscopy and raman spectroscopy. The formed CPs were turbostratic in nature, with a large number of functional groups on the surface. We explored the adsorption characteristics of the formed CPs for wastewater treatment. Because of the negative surface of the CPs, as evident from the zeta value, it is possible to use them for selective adsorption of the cationic dye methylene blue from a mixture of dyes. The equilibrium adsorption isotherm revealed that the Langmuir model better describes the adsorption process than the Freundlich model. As-prepared CPs rapidly adsorbed ~84% of the methylene blue within 1 min and can be regenerated and used repeatedly. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
An easily regenerable enzyme reactor prepared from polymerized high internal phase emulsions.
Ruan, Guihua; Wu, Zhenwei; Huang, Yipeng; Wei, Meiping; Su, Rihui; Du, Fuyou
2016-04-22
A large-scale high-efficient enzyme reactor based on polymerized high internal phase emulsion monolith (polyHIPE) was prepared. First, a porous cross-linked polyHIPE monolith was prepared by in-situ thermal polymerization of a high internal phase emulsion containing styrene, divinylbenzene and polyglutaraldehyde. The enzyme of TPCK-Trypsin was then immobilized on the monolithic polyHIPE. The performance of the resultant enzyme reactor was assessed according to the conversion ability of Nα-benzoyl-l-arginine ethyl ester to Nα-benzoyl-l-arginine, and the protein digestibility of bovine serum albumin (BSA) and cytochrome (Cyt-C). The results showed that the prepared enzyme reactor exhibited high enzyme immobilization efficiency and fast and easy-control protein digestibility. BSA and Cyt-C could be digested in 10 min with sequence coverage of 59% and 78%, respectively. The peptides and residual protein could be easily rinsed out from reactor and the reactor could be regenerated easily with 4 M HCl without any structure destruction. Properties of multiple interconnected chambers with good permeability, fast digestion facility and easily reproducibility indicated that the polyHIPE enzyme reactor was a good selector potentially applied in proteomics and catalysis areas. Copyright © 2016 Elsevier Inc. All rights reserved.
Hekmat, Dariusch; Breitschwerdt, Peter; Weuster-Botz, Dirk
2015-09-01
To investigate quantitatively and reproducibly a scalable, preparative crystallization method in novel stirred tanks using three different protein solutions containing residual microbial host cell proteins (HCP). Lysozyme from solutions being spiked with up to 15% host cell proteins (HCP) (corresponding to 176,500 ppm) was crystallized within a 2.4-4.6 h at 93.7% yield using NaCl and glycerol. Lipase was crystallized under comparable conditions using NaCl and a mixture of two polyethylene glycols (PEG). Enhanced green fluorescent protein (eGFP) was overexpressed in E. coli yielding a solution containing 23% target protein. Residual HCP content after pre-treatment was 7-16%. eGFP was crystallized from these solutions within 1.75-4 h at 88.7% step yield using ethanol and the same mixture of two PEG as in the case of lipase. HCP contained in the solvent channels of the protein crystals could be removed by diffusive washing yielding final purities at or above 99%. Preparative crystallization can be carried out with fast kinetics and high yields from solutions containing residual impurities and may represent an attractive alternative purification method compared to preparative chromatography, especially at large production scales.
Application of preparative disk gel electrophoresis for antigen purification from inclusion bodies.
Okegawa, Yuki; Koshino, Masanori; Okushima, Teruya; Motohashi, Ken
2016-02-01
Specific antibodies are a reliable tool to examine protein expression patterns and to determine the protein localizations within cells. Generally, recombinant proteins are used as antigens for specific antibody production. However, recombinant proteins from mammals and plants are often overexpressed as insoluble inclusion bodies in Escherichia coli. Solubilization of these inclusion bodies is desirable because soluble antigens are more suitable for injection into animals to be immunized. Furthermore, highly purified proteins are also required for specific antibody production. Plastidic acetyl-CoA carboxylase (ACCase: EC 6.4.1.2) from Arabidopsis thaliana, which catalyzes the formation of malonyl-CoA from acetyl-CoA in chloroplasts, formed inclusion bodies when the recombinant protein was overexpressed in E. coli. To obtain the purified protein to use as an antigen, we applied preparative disk gel electrophoresis for protein purification from inclusion bodies. This method is suitable for antigen preparation from inclusion bodies because the purified protein is recovered as a soluble fraction in electrode running buffer containing 0.1% sodium dodecyl sulfate that can be directly injected into immune animals, and it can be used for large-scale antigen preparation (several tens of milligrams). Copyright © 2015 Elsevier Inc. All rights reserved.
Facile synthesis of Fe3O4@C hollow nanospheres and their application in polluted water treatment
NASA Astrophysics Data System (ADS)
Zhang, Yuanguang; Xu, Shihao; Xia, Hongyu; Zheng, Fangcai
2016-11-01
Nanostructured carbon-based materials, such as carbon nanotube arrays have shown respectable removal ability for heavy metal ions and organic dyes in aqueous solution. Although the carbon-based materials exhibited excellent removal ability, the separation of them from the aqueous solution is difficult and time-consuming. Here we demonstrated a novel and facile route for the large-scale fabrication of Fe3O4@C hollow nanospheres, with using ferrocene as a single reagent and SiO2 as a template. The as-prepared Fe3O4@C hollow nanospheres exhibited adsorption ability for heavy metal ions and organic dyes from aqueous solution, and can be easily separated by an external magnet. When the as-prepared Fe3O4@C hollow nanospheres were mixed with the aqueous solution of Hg2+ within 15 min, the removal efficiency was 90.3%. The as-prepared Fe3O4@C hollow nanospheres were also exhibited a high adsorption capacity (100%) as the adsorbent for methylene blue (MB). In addition, the as-prepared Fe3O4@C hollow nanospheres can be used as the recyclable sorbent for water treatment via a simple magnetic separation.
Green chemistry approach for the synthesis of biocompatible graphene
Gurunathan, Sangiliyandi; Han, Jae Woong; Kim, Jin-Hoi
2013-01-01
Background Graphene is a single-atom thick, two-dimensional sheet of hexagonally arranged carbon atoms isolated from its three-dimensional parent material, graphite. One of the most common methods for preparation of graphene is chemical exfoliation of graphite using powerful oxidizing agents. Generally, graphene is synthesized through deoxygenation of graphene oxide (GO) by using hydrazine, which is one of the most widespread and strongest reducing agents. Due to the high toxicity of hydrazine, it is not a promising reducing agent in large-scale production of graphene; therefore, this study focused on a green or sustainable synthesis of graphene and the biocompatibility of graphene in primary mouse embryonic fibroblast cells (PMEFs). Methods Here, we demonstrated a simple, rapid, and green chemistry approach for the synthesis of reduced GO (rGO) from GO using triethylamine (TEA) as a reducing agent and stabilizing agent. The obtained TEA reduced GO (TEA-rGO) was characterized by ultraviolet (UV)–visible absorption spectroscopy, X-ray diffraction (XRD), particle size dynamic light scattering (DLS), scanning electron microscopy (SEM), Raman spectroscopy, and atomic force microscopy (AFM). Results The transition of graphene oxide to graphene was confirmed by UV–visible spectroscopy. XRD and SEM were used to investigate the crystallinity of graphene and the surface morphologies of prepared graphene respectively. The formation of defects further supports the functionalization of graphene as indicated in the Raman spectrum of TEA-rGO. Surface morphology and the thickness of the GO and TEA-rGO were analyzed using AFM. The presented results suggest that TEA-rGO shows significantly more biocompatibility with PMEFs cells than GO. Conclusion This is the first report about using TEA as a reducing as well as a stabilizing agent for the preparation of biocompatible graphene. The proposed safe and green method offers substitute routes for large-scale production of graphene for several biomedical applications. PMID:23940417
NM-Scale Anatomy of an Entire Stardust Carrot Track
NASA Technical Reports Server (NTRS)
Nakamura-Messenger, K.; Keller, L. P.; Clemett, S. J.; Messenger, S.
2009-01-01
Comet Wild-2 samples collected by NASA s Stardust mission are extremely complex, heterogeneous, and have experienced wide ranges of alteration during the capture process. There are two major types of track morphologies: "carrot" and "bulbous," that reflect different structural/compositional properties of the impactors. Carrot type tracks are typically produced by compact or single mineral grains which survive essentially intact as a single large terminal particle. Bulbous tracks are likely produced by fine-grained or organic-rich impactors [1]. Owing to their challenging nature and especially high value of Stardust samples, we have invested considerable effort in developing both sample preparation and analytical techniques tailored for Stardust sample analyses. Our report focuses on our systematic disassembly and coordinated analysis of Stardust carrot track #112 from the mm to nm-scale.
Large Area Few Layers Hexagonal Boron Nitride Prepared by Quadrupole Field Aided Exfoliation.
Hanlun, Lu; Rong, Min Zhi; Zhang, Ming Qiu
2018-01-16
A quadrupole electric field mediated exfoliation method is proposed to convert micron sized hexagonal boron nitride (hBN) powders into few layers hexagonal boron nitride nano-sheets (h-BNNS). Under the optimum conditions (400 Hz, 40 V, 32μg/mL, sodium deoxycholate, TAE medium), the hBN powders (thickness > 200 nm, horizontal scale ~ 10 μm) are successfully exfoliated into 0.5-4 nm (1-10 layers) thick h-BNNS with the same horizontal scale. Dynamic laser scattering (DLS) and atomic force microscope (AFM) statistics show that the yield is 47.6 % (for the portion with the thickness of 0.5-6 nm), and all of the vertical sizes are reduced to smaller than 18 nm (45 layers). © 2018 IOP Publishing Ltd.
A new and fast method for preparing high quality lambda DNA suitable for sequencing.
Manfioletti, G; Schneider, C
1988-01-01
A method is described for the rapid purification of high quality lambda DNA. The method can be used from either liquid or plate lysates and on a small scale or a large scale. It relies on the preadsobtion of all polyanions present in the lysate to an "insoluble" anion-exchange matrix (DEAE or TEAE). Phage particles are then disrupted by combined treatment with EDTA/proteinase K and the resulting DNA is precipitated by the addition of the cationic detergent cetyl (or hexadecyl)-trimethyl ammonium bromide-CTAB ("soluble" anion-exchange matrix). The precipitated CTAB-DNA complex is then exchanged to Na-DNA and ethanol precipitated. The resultant purified DNA is suitable for enzymatic reactions and provides a high quality template for dideoxy-sequence analysis. Images PMID:2966928
NASA Astrophysics Data System (ADS)
Xuan, Ming-dong; Dai, Long-gui; Jia, Hai-qiang; Chen, Hong
2014-01-01
Periodic triangle truncated pyramid arrays are successfully fabricated on the sapphire substrate by a low-cost and high-efficiency laser interference lithography (LIL) system. Through the combination of dry etching and wet etching techniques, the nano-scale patterned sapphire substrate (NPSS) with uniform size is prepared. The period of the patterns is 460 nm as designed to match the wavelength of blue light emitting diode (LED). By improving the stability of the LIL system and optimizing the process parameters, well-defined triangle truncated pyramid arrays can be achieved on the sapphire substrate with diameter of 50.8 mm. The deviation of the bottom width of the triangle truncated pyramid arrays is 6.8%, which is close to the industrial production level of 3%.
Jankowski, Stéphane; Currie-Fraser, Erica; Xu, Licen; Coffa, Jordy
2008-01-01
Annotated DNA samples that had been previously analyzed were tested using multiplex ligation-dependent probe amplification (MLPA) assays containing probes targeting BRCA1, BRCA2, and MMR (MLH1/MSH2 genes) and the 9p21 chromosomal region. MLPA polymerase chain reaction products were separated on a capillary electrophoresis platform, and the data were analyzed using GeneMapper v4.0 software (Applied Biosystems, Foster City, CA). After signal normalization, loci regions that had undergone deletions or duplications were identified using the GeneMapper Report Manager and verified using the DyeScale functionality. The results highlight an easy-to-use, optimal sample preparation and analysis workflow that can be used for both small- and large-scale studies. PMID:19137113
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Haoting; Liao, Qilong, E-mail: liaoqilong@swust.edu.cn; Dai, Yunya
2016-04-15
Highlights: • Millimeter-scale translucent La{sub 2}O{sub 3}-doped Al{sub 2}O{sub 3} hollow spheres have been prepared. • The diameters of the prepared hollow spheres are 500–1300μm. • The degree of sphericity for the prepared hollow spheres is above 98%. • The mechanisms of transparency are discussed. - Abstract: Millimeter-scale translucent La{sub 2}O{sub 3}-doped Al{sub 2}O{sub 3} ceramic hollow spheres have been successfully prepared using the oil-in-water (paraffin-in-alumina sol) droplets as precursors made by self-made T-shape micro-emulsion device. The main crystalline phase of the obtained hollow sphere is alpha alumina. The prepared translucent La{sub 2}O{sub 3}-containing Al{sub 2}O{sub 3} ceramic hollow spheresmore » have diameters of 500–1300 μm, wall thickness of about 23 μm and the degree of sphericity of above 98%. With the increase of the La{sub 2}O{sub 3} content, grains and grain-boundaries of the alumina spherical shell for the prepared millimeter-scale hollow spheres become regular and clear gradually. When the La{sub 2}O{sub 3} content is 0.1 wt.%, the crystal surface of the obtained Al{sub 2}O{sub 3} spherical shell shows optimal grains and few pores, and its transmittance reaches 42% at 532 nm laser light. This method provides a promising technique of preparing millimeter-scale translucent ceramic hollow spheres for laser inertial confined fusion.« less
Self-guaranteed measurement-based quantum computation
NASA Astrophysics Data System (ADS)
Hayashi, Masahito; Hajdušek, Michal
2018-05-01
In order to guarantee the output of a quantum computation, we usually assume that the component devices are trusted. However, when the total computation process is large, it is not easy to guarantee the whole system when we have scaling effects, unexpected noise, or unaccounted for correlations between several subsystems. If we do not trust the measurement basis or the prepared entangled state, we do need to be worried about such uncertainties. To this end, we propose a self-guaranteed protocol for verification of quantum computation under the scheme of measurement-based quantum computation where no prior-trusted devices (measurement basis or entangled state) are needed. The approach we present enables the implementation of verifiable quantum computation using the measurement-based model in the context of a particular instance of delegated quantum computation where the server prepares the initial computational resource and sends it to the client, who drives the computation by single-qubit measurements. Applying self-testing procedures, we are able to verify the initial resource as well as the operation of the quantum devices and hence the computation itself. The overhead of our protocol scales with the size of the initial resource state to the power of 4 times the natural logarithm of the initial state's size.
Soviet space flight: the human element.
Garshnek, V
1988-05-01
Building on past experience and knowledge, the Soviet manned space flight effort has become broad, comprehensive, and forward-looking. Their long-running space station program has provided the capabilities to investigate long-term effects of microgravity on human physiology and behavior and test various countermeasures against microgravity-induced physiological deconditioning. Since the beginning of Soviet manned space flight, the biomedical training and preparation of cosmonauts has evolved from a process that increased human tolerance to space flight factors, to a system of interrelated measures to prepare cosmonauts physically and psychologically to live and work in space. Currently, the Soviet Union is constructing a multimodular space station, the Mir. With the emergence of dedicated laboratory modules, the Soviets have begun the transition from small-scale experimental research to large-scale production activities and specialized scientific work in space. In the future, additional laboratory modules will be added, including one dedicated to biomedical research, called the "Medilab." The longest manned space flight to date (326 days) has been completed by the Soviets. The biomedical effects of previous long-duration flights, and perhaps those of still greater length, may contribute important insight ito the possibility of extended missions beyond Earth, such as a voyage to Mars.
Controllable Synthesis of Highly Luminescent Boron Nitride Quantum Dots.
Li, Hongling; Tay, Roland Yingjie; Tsang, Siu Hon; Zhen, Xu; Teo, Edwin Hang Tong
2015-12-22
Boron nitride quantum dots (BNQDs), as a new member of heavy metal-free quantum dots, have aroused great interest in fundamental research and practical application due to their unique physical/chemical properties. However, it is still a challenge to controllably synthesize high-quality BNQDs with high quantum yield (QY), uniform size and strong fluorescent. In this work, BNQDs have been successfully fabricated by the liquid exfoliation and the subsequent solvothermal process with respect to its facileness and easy large scale up. Importantly, BNQDs with high-quality can be controllably obtained by adjusting the synthetic parameters involved in the solvothermal process including filling factor, synthesis temperature, and duration time. Encouragingly, the as-prepared BNQDs possess strong blue luminescence with QY as high as 19.5%, which can be attributed to the synergetic effect of size, surface chemistry and edge defects. In addition, this strategy presented here provides a new reference for the controllable synthesis of other heavy metal-free QDs. Furthermore, the as-prepared BNQDs are non-toxic to cells and exhibit nanosecond-scaled lifetimes, suggesting they have great potential biological and optoelectronic applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Ma, Hongmin; Hao, Jingcheng
2011-11-01
Self-assembly is now being intensively studied in chemistry, physics, biology, and materials engineering and has become an important "bottom-up" approach to create intriguing structures for different applications. Self-assembly is not only a practical approach for creating a variety of nanostructures, but also shows great superiority in building hierarchical structures with orders on different length scales. The early work in self-assembly focused on molecular self-assembly in bulk solution, including the resultant dye aggregates, liposomes, vesicles, liquid crystals, gels and so on. Interfacial self-assembly has been a great concern over the last two decades, largely because of the unique and ingenious roles of this method for constructing materials at interfaces, such as self-assembled monolayers, Langmuir-Blodgett films, and capsules. Nanocrystal superlattices, honeycomb films and coffee rings are intriguing structural materials with more complex features and can be prepared by interfacial self-assembly on different length scales. In this critical review, we outline the recent development in the preparation and application of colloidal nanocrystal superlattices, honeycomb-patterned macroporous structures by the breath figure method, and coffee-ring-like patterns (247 references). This journal is © The Royal Society of Chemistry 2011
Light-cured polymer electrolytes for safe, low-cost and sustainable sodium-ion batteries
NASA Astrophysics Data System (ADS)
Colò, Francesca; Bella, Federico; Nair, Jijeesh R.; Gerbaldi, Claudio
2017-10-01
In this work we present a very simple preparation procedure of a poly(ethylene oxide) (PEO)-based crosslinked polymer electrolyte (XPE) for application in sodium-ion batteries (NIBs). The polymer electrolyte, containing NaClO4 as Na+ source, is prepared by rapid, energy saving, solvent-free photopolymerization technique, in a single step. Thermal, mechanical, morphological and electrochemical properties of the resulting XPE are thoroughly investigated. The highly ionic conducting (>1 mS cm-1 at 25 °C) polymer electrolyte is used in a lab-scale sodium cell with nanostructured TiO2 working electrode. The obtained results in terms of ambient temperature cycling behaviour (stable specific capacity of about 250 mAh g-1 at 0.1 mA cm-2 and overall remarkable stability, for a quasi-solid state Na polymer cell, upon very long term cycling exceeding 1000 reversible cycles at 0.5 mA cm-2 corresponding to > 5000 h of continuous operation) demonstrate the promising prospects of this novel XPE to be implemented in the next-generation NIBs conceived for large-scale energy storage systems, such as those connected to photovoltaic and wind factories.
Nonlinear optical microscopy and ultrasound imaging of human cervical structure
NASA Astrophysics Data System (ADS)
Reusch, Lisa M.; Feltovich, Helen; Carlson, Lindsey C.; Hall, Gunnsteinn; Campagnola, Paul J.; Eliceiri, Kevin W.; Hall, Timothy J.
2013-03-01
The cervix softens and shortens as its collagen microstructure rearranges in preparation for birth, but premature change may lead to premature birth. The global preterm birth rate has not decreased despite decades of research, likely because cervical microstructure is poorly understood. Our group has developed a multilevel approach to evaluating the human cervix. We are developing quantitative ultrasound (QUS) techniques for noninvasive interrogation of cervical microstructure and corroborating those results with high-resolution images of microstructure from second harmonic generation imaging (SHG) microscopy. We obtain ultrasound measurements from hysterectomy specimens, prepare the tissue for SHG, and stitch together several hundred images to create a comprehensive view of large areas of cervix. The images are analyzed for collagen orientation and alignment with curvelet transform, and registered with QUS data, facilitating multiscale analysis in which the micron-scale SHG images and millimeter-scale ultrasound data interpretation inform each other. This novel combination of modalities allows comprehensive characterization of cervical microstructure in high resolution. Through a detailed comparative study, we demonstrate that SHG imaging both corroborates the quantitative ultrasound measurements and provides further insight. Ultimately, a comprehensive understanding of specific microstructural cervical change in pregnancy should lead to novel approaches to the prevention of preterm birth.
The end-stage renal disease industry and exit strategies for nephrologists.
Sullivan, John D
2006-01-01
The purpose of this presentation is to identify exit strategies for nephrologists under changing conditions in the dialysis market. The end-stage renal disease service provider market continues to be highly receptive to consolidation. Taking advantage of large economies of scale, large for-profit dialysis chains have surpassed independent operators in both number of clinics and total patients. With relatively low barriers to entry, new smaller clinics continue to open, serving a niche outside the larger chains. Additional competition comes in the form of medium players funded by venture capitalists with the added pressure of rapid growth and financial return. To ensure market power in both dialysis products and managed care negotiation leverage, medium and large service providers will continue to seek out attractive acquisition targets. For nephrologists to capitalize on investment, clinic and business preparation will continue to be the driving force for these divestitures.
A Magnetic Bead-Integrated Chip for the Large Scale Manufacture of Normalized esiRNAs
Wang, Zhao; Huang, Huang; Zhang, Hanshuo; Sun, Changhong; Hao, Yang; Yang, Junyu; Fan, Yu; Xi, Jianzhong Jeff
2012-01-01
The chemically-synthesized siRNA duplex has become a powerful and widely used tool for RNAi loss-of-function studies, but suffers from a high off-target effect problem. Recently, endoribonulease-prepared siRNA (esiRNA) has been shown to be an attractive alternative due to its lower off-target effect and cost effectiveness. However, the current manufacturing method for esiRNA is complicated, mainly in regards to purification and normalization on a large-scale level. In this study, we present a magnetic bead-integrated chip that can immobilize amplification or transcription products on beads and accomplish transcription, digestion, normalization and purification in a robust and convenient manner. This chip is equipped to manufacture ready-to-use esiRNAs on a large-scale level. Silencing specificity and efficiency of these esiRNAs were validated at the transcriptional, translational and functional levels. Manufacture of several normalized esiRNAs in a single well, including those silencing PARP1 and BRCA1, was successfully achieved, and the esiRNAs were subsequently utilized to effectively investigate their synergistic effect on cell viability. A small esiRNA library targeting 68 tyrosine kinase genes was constructed for a loss-of-function study, and four genes were identified in regulating the migration capability of Hela cells. We believe that this approach provides a more robust and cost-effective choice for manufacturing esiRNAs than current approaches, and therefore these heterogeneous RNA strands may have utility in most intensive and extensive applications. PMID:22761791
Dynamics of a vertical-flow windrow vermicomposting system.
Hanc, Ales; Castkova, Tereza; Kuzel, Stanislav; Cajthaml, Tomas
2017-11-01
Large-scale vermicomposting under outdoor conditions may differ from small-scale procedures in the laboratory. The present study evaluated changes in selected properties of a large-scale vertical-flow windrow vermicomposting system with continuous feeding with household biowaste. The windrow profile was divided into five layers of differing thickness and age after more than 12 months of vermicomposting. The top layer (0-30 cm, age <3 months) was characterised by partially decomposed organic matter with a high pH value and an elevated carbon/nitrogen (C/N) ratio. The earthworm biomass was 15 g kg -1 with a population density of 125 earthworms per kilogram predominantly found in clusters. The greatest amount of fungi (3.5 µg g -1 dw) and bacteria (62 µg g -1 dw) (expressed as phospholipid fatty acid analysis) was found in this layer. Thus, the top layer could be used for an additional cycle of windrow vermicomposting and for the preparation of aqueous extracts to protect plants against diseases. The lower layers (graduated by 30 cm and by 3 months of age) were mature as reflected by the low content of ammonia nitrogen, ratio of ammonia to nitrate nitrogen and dissolved organic carbon, and high ion-exchange capacity and its ratio to carbon. These layers were characterised by elevated values for electrical conductivity, total content of nutrients, available magnesium content, and a relatively large bacterial/fungal ratio. On the basis of the observed properties, the bottom layers were predetermined as effective fertilisers.
Ezzatifar, Fatemeh; Majidi, Jafar; Baradaran, Behzad; Aghebati Maleki, Leili; Abdolalizadeh, Jalal; Yousefi, Mehdi
2015-01-01
Purpose: Monoclonal antibodies are potentially powerful tools used in biomedical research, diagnosis, and treatment of infectious diseases and cancers. The monoclonal antibody against Human IgA can be used as a diagnostic application to detect infectious diseases. The aim of this study was to improve an appropriate protocol for large-scale production of mAbs against IgA. Methods: For large-scale production of the monoclonal antibody, hybridoma cells that produce monoclonal antibodies against Human IgA were injected intraperitoneally into Balb/c mice that were previously primed with 0.5 ml Pristane. After ten days, ascitic fluid was harvested from the peritoneum of each mouse. The ELISA method was carried out for evaluation of the titration of produced mAbs. The ascitic fluid was investigated in terms of class and subclass by a mouse mAb isotyping kit. MAb was purified from the ascitic fluid by ion exchange chromatography. The purity of the monoclonal antibody was confirmed by SDS-PAGE, and the purified monoclonal antibody was conjugated with HRP. Results: Monoclonal antibodies with high specificity and sensitivity against Human IgA were prepared by hybridoma technology. The subclass of antibody was IgG1 and its light chain was the kappa type. Conclusion: This conjugated monoclonal antibody could have applications in designing ELISA kits in order to diagnose different infectious diseases such as toxoplasmosis and H. Pylori. PMID:25789225
NASA Astrophysics Data System (ADS)
Mortensen, Eric; Wu, Shu; Notaro, Michael; Vavrus, Stephen; Montgomery, Rob; De Piérola, José; Sánchez, Carlos; Block, Paul
2018-01-01
Located at a complex topographic, climatic, and hydrologic crossroads, southern Peru is a semiarid region that exhibits high spatiotemporal variability in precipitation. The economic viability of the region hinges on this water, yet southern Peru is prone to water scarcity caused by seasonal meteorological drought. Meteorological droughts in this region are often triggered during El Niño episodes; however, other large-scale climate mechanisms also play a noteworthy role in controlling the region's hydrologic cycle. An extensive season-ahead precipitation prediction model is developed to help bolster the existing capacity of stakeholders to plan for and mitigate deleterious impacts of drought. In addition to existing climate indices, large-scale climatic variables, such as sea surface temperature, are investigated to identify potential drought predictors. A principal component regression framework is applied to 11 potential predictors to produce an ensemble forecast of regional January-March precipitation totals. Model hindcasts of 51 years, compared to climatology and another model conditioned solely on an El Niño-Southern Oscillation index, achieve notable skill and perform better for several metrics, including ranked probability skill score and a hit-miss statistic. The information provided by the developed model and ancillary modeling efforts, such as extending the lead time of and spatially disaggregating precipitation predictions to the local level as well as forecasting the number of wet-dry days per rainy season, may further assist regional stakeholders and policymakers in preparing for drought.
Towards Simulating the Transverse Ising Model in a 2D Array of Trapped Ions
NASA Astrophysics Data System (ADS)
Sawyer, Brian
2013-05-01
Two-dimensional Coulomb crystals provide a useful platform for large-scale quantum simulation. Penning traps enable confinement of large numbers of ions (>100) and allow for the tunable-range spin-spin interactions demonstrated in linear ion strings, facilitating simulation of quantum magnetism at a scale that is currently intractable on classical computers. We readily confine hundreds of Doppler laser-cooled 9Be+ within a Penning trap, producing a planar array of ions with self-assembled triangular order. The transverse ``drumhead'' modes of our 2D crystal along with the valence electron spin of Be+ serve as a resource for generating spin-motion and spin-spin entanglement. Applying a spin-dependent optical dipole force (ODF) to the ion array, we perform spectroscopy and thermometry of individual drumhead modes. This ODF also allows us to engineer long-range Ising spin couplings of either ferromagnetic or anti-ferromagnetic character whose approximate power-law scaling with inter-ion distance, d, may be varied continuously from 1 /d0 to 1 /d3. An effective transverse magnetic field is applied via microwave radiation at the ~124-GHz spin-flip frequency, and ground states of the effective Ising Hamiltonian may in principle be prepared adiabatically by slowly decreasing this transverse field in the presence of the induced Ising coupling. Long-range anti-ferromagnetic interactions are of particular interest due to their inherent spin frustration and resulting large, near-degenerate manifold of ground states. We acknowledge support from NIST and the DARPA-OLE program.
de Moura, Diogo Turiani; Guedes, Hugo; Tortoretto, Verônica; Arataque, Tayrê Pádua; de Moura, Eduardo Guimarães; Román, Juan Pablo; Rodela, Gustavo Luis; Artifon, Everson L
2016-01-01
The purpose of the present study is to compare intestinal preparation with mannitol and sodium picosulphate, assessing patient's acceptance, side effects and cleaning capacity. This is a prospective, nom randomized, blind study, in which the evaluator had no information about the preparation applied. The sample obtained was divided into two groups according to the bowel preparation applied, with 153 patients prepared with 10% mannitol and 84 patients with sodium picosulfate. The evaluation of colon preparation was done using the Boston Scale (Boston Bowel Preparation Scale - BBP) through a three-point scoring system for each of the three regions of the colon: right, left and transverse colon. Of the 237 patients that were evaluated, 146 (61.60%) were female and 91 (38.4%) were male. Regarding the group that used mannitol, 98 were female (64.05%) and 55 were male (35.95%). Among the patients who used sodium picosulfate, 48 were female (57.14%) and 36 were male (42.86%), with no statistical differences between both groups (p> 0.32). Considering that an adequate preparation scores ≥ 6 in the Boston Scale, the bowel cleansing preparation was satisfactory in both groups. 93% of the patients who used mannitol and 81% of the patients who used sodium picosulfate had adequate preparation (score of ≥ 6). Moreover, we consider that the average score in the preparation with Mannitol was 9, while the sodium picosulfate score was 7. There were no significant differences between the two groups. There is consensus among authors who state that colonoscopy's safety and success are highly related to the cleansing outcome, regardless of the method used. The same can be observed in the present study, on which both preparations were proved safe and effective for bowel cleansing, according to the Boston scale, as well as accepted by patients and free of complications.
Bridging the Science/Policy Gap through Boundary Chain Partnerships and Communities of Practice
NASA Astrophysics Data System (ADS)
Kalafatis, S.
2014-12-01
Generating the capacity to facilitate the informed usage of climate change science by decision makers on a large scale is fast becoming an area of great concern. While research demonstrates that sustained interactions between producers of such information and potential users can overcome barriers to information usage, it also demonstrates the high resource demand of these efforts. Our social science work at Great Lakes Integrated Sciences and Assessments (GLISA) sheds light on scaling up the usability of climate science through two research areas. The first focuses on partnerships with other boundary organizations that GLISA has leveraged - the "boundary chains" approach. These partnerships reduce the transaction costs involved with outreach and have enhanced the scope of GLISA's climate service efforts to encompass new users such as First Nations groups in Wisconsin and Michigan and underserved neighborhoods in St. Paul, Minnesota. The second research area looks at the development of information usability across the regional scale of the eight Great Lakes states. It has identified the critical role that communities of practice are playing in making information usable to large groups of users who work in similar contexts and have similar information needs. Both these research areas demonstrate the emerging potential of flexible knowledge networks to enhance society's ability to prepare for the impacts of climate change.
Liu, Xian-Wei; Sun, Xue-Fei; Huang, Yu-Xi; Sheng, Guo-Ping; Zhou, Kang; Zeng, Raymond J; Dong, Fang; Wang, Shu-Guang; Xu, An-Wu; Tong, Zhong-Hua; Yu, Han-Qing
2010-10-01
Microbial fuel cells (MFCs) provide new opportunities for the simultaneous wastewater treatment and electricity generation. Enhanced oxygen reduction capacity of cost-effective metal-based catalysts in an air cathode is essential for the scale-up and commercialization of MFCs in the field of wastewater treatment. We demonstrated that a nano-structured MnO(x) material, prepared by an electrochemically deposition method, could be an effective catalyst for oxygen reduction in an MFC to generate electricity with the maximum power density of 772.8 mW/m(3) and remove organics when the MFC was fed with an acetate-laden synthetic wastewater. The nano-structured MnO(x) with the controllable size and morphology could be readily obtained with the electrochemical deposition method. Both morphology and manganese oxidation state of the nano-scale catalyst were largely dependent on the electrochemical preparation process, and they governed its catalytic activity and the cathodic oxygen reduction performance of the MFC accordingly. Furthermore, cyclic voltammetry (CV) performed on each nano-structured material suggests that the MnO(x) nanorods had an electrochemical activity towards oxygen reduction reaction via a four-electron pathway in a neutral pH solution. This work provides useful information on the facile preparation of cost-effective cathodic catalysts in a controllable way for the single-chamber air-cathode MFC for wastewater treatment. Copyright © 2010 Elsevier Ltd. All rights reserved.
An Evaluation of a 4-8 Mathematics Teacher Preparation Program at a Large State Institution in Texas
ERIC Educational Resources Information Center
Lim, Woong
2011-01-01
This study provided a springboard for future teacher preparation evaluation studies by examining the 4-8 mathematics teacher preparation component of the teacher preparation program at a large state institution in Texas. The research questions for this study were: (1) To what extent is the 4-8 mathematics teacher preparation program consistent…
A follow-up study of hygiene in catering premises at large-scale events in the United Kingdom.
Willis, C; Elviss, N; McLauchlin, J
2015-01-01
To investigate food hygiene practices at large events by assessing the microbiological quality of ready-to-eat food, drinking water, food preparation surfaces, cleaning cloths and wristbands worn by food handlers for event security purposes. Over a 7-month period, 1662 samples were collected at 153 events and examined for microbiological contamination. Eight per cent of food samples were of an unsatisfactory quality. A further one per cent contained potentially hazardous levels of human pathogenic bacteria. 27% of water samples, 32% of swabs and 56% of cloths were also unsatisfactory. These results represented an improvement in hygiene compared to a previous study carried out 12 months previously. A fifth of food handler wristbands were contaminated with Enterobacteriaceae, Escherichia coli and/or coagulase-positive staphylococci, with those bands made from fabric being more frequently contaminated than those made from plastic or other materials. This study provides evidence that the food hygiene at large-scale events may have improved. However, there is still a need for continued efforts to maintain an ongoing improvement in cleaning regimes and food hygiene management. This study was part of an ongoing focus on large events in the lead-up to the London 2012 Olympics. Lessons learnt here will be important in the planning of future large events. © 2014 Crown copyright. © 2014 Society for Applied Microbiology This article is Published with the permission of the Controller of HMSO and Queen's Printer for Scotland.
A Surgical Procedure for Resecting the Mouse Rib: A Model for Large-Scale Long Bone Repair
Funnell, John W.; Thein, Thu Zan Tun; Mariani, Francesca V.
2015-01-01
This protocol introduces researchers to a new model for large-scale bone repair utilizing the mouse rib. The procedure details the following: preparation of the animal for surgery, opening the thoracic body wall, exposing the desired rib from the surrounding intercostal muscles, excising the desired section of rib without inducing a pneumothorax, and closing the incisions. Compared to the bones of the appendicular skeleton, the ribs are highly accessible. In addition, no internal or external fixator is necessary since the adjacent ribs provide a natural fixation. The surgery uses commercially available supplies, is straightforward to learn, and well-tolerated by the animal. The procedure can be carried out with or without removing the surrounding periosteum, and therefore the contribution of the periosteum to repair can be assessed. Results indicate that if the periosteum is retained, robust repair occurs in 1 - 2 months. We expect that use of this protocol will stimulate research into rib repair and that the findings will facilitate the development of new ways to stimulate bone repair in other locations around the body. PMID:25651082
Miri, Andrew; Daie, Kayvon; Burdine, Rebecca D.; Aksay, Emre
2011-01-01
The advent of methods for optical imaging of large-scale neural activity at cellular resolution in behaving animals presents the problem of identifying behavior-encoding cells within the resulting image time series. Rapid and precise identification of cells with particular neural encoding would facilitate targeted activity measurements and perturbations useful in characterizing the operating principles of neural circuits. Here we report a regression-based approach to semiautomatically identify neurons that is based on the correlation of fluorescence time series with quantitative measurements of behavior. The approach is illustrated with a novel preparation allowing synchronous eye tracking and two-photon laser scanning fluorescence imaging of calcium changes in populations of hindbrain neurons during spontaneous eye movement in the larval zebrafish. Putative velocity-to-position oculomotor integrator neurons were identified that showed a broad spatial distribution and diversity of encoding. Optical identification of integrator neurons was confirmed with targeted loose-patch electrical recording and laser ablation. The general regression-based approach we demonstrate should be widely applicable to calcium imaging time series in behaving animals. PMID:21084686
Network-based approaches to climate knowledge discovery
NASA Astrophysics Data System (ADS)
Budich, Reinhard; Nyberg, Per; Weigel, Tobias
2011-11-01
Climate Knowledge Discovery Workshop; Hamburg, Germany, 30 March to 1 April 2011 Do complex networks combined with semantic Web technologies offer the next generation of solutions in climate science? To address this question, a first Climate Knowledge Discovery (CKD) Workshop, hosted by the German Climate Computing Center (Deutsches Klimarechenzentrum (DKRZ)), brought together climate and computer scientists from major American and European laboratories, data centers, and universities, as well as representatives from industry, the broader academic community, and the semantic Web communities. The participants, representing six countries, were concerned with large-scale Earth system modeling and computational data analysis. The motivation for the meeting was the growing problem that climate scientists generate data faster than it can be interpreted and the need to prepare for further exponential data increases. Current analysis approaches are focused primarily on traditional methods, which are best suited for large-scale phenomena and coarse-resolution data sets. The workshop focused on the open discussion of ideas and technologies to provide the next generation of solutions to cope with the increasing data volumes in climate science.
NASA Astrophysics Data System (ADS)
Ruan, Dianbo; Kim, Myeong-Seong; Yang, Bin; Qin, Jun; Kim, Kwang-Bum; Lee, Sang-Hyun; Liu, Qiuxiang; Tan, Lei; Qiao, Zhijun
2017-10-01
To address the large-scale application demands of high energy density, high power density, and long cycle lifetime, 700-F hybrid capacitor pouch cells have been prepared, comprising ∼240-μm-thick activated carbon cathodes, and ∼60-μm-thick Li4Ti5O12 anodes. Microspherical Li4Ti5O12 (M-LTO) synthesized by spray-drying features 200-400 nm primary particles and interconnected nanopore structures. M-LTO half-cells exhibits high specific capacities (175 mAhh g-1), good rate capabilities (148 mAhh g-1 at 20 C), and ultra-long cycling stabilities (90% specific capacity retention after 10,000 cycles). In addition, the obtained hybrid capacitors comprising activated carbon (AC) and M-LTO shows excellent cell performances, achieving a maximum energy density of 51.65 Wh kg-1, a maximum power density of 2466 W kg-1, and ∼92% capacitance retention after 10,000 cycles, thus meeting the demands for large-scale applications such as trolleybuses.
Large area sub-micron chemical imaging of magnesium in sea urchin teeth.
Masic, Admir; Weaver, James C
2015-03-01
The heterogeneous and site-specific incorporation of inorganic ions can profoundly influence the local mechanical properties of damage tolerant biological composites. Using the sea urchin tooth as a research model, we describe a multi-technique approach to spatially map the distribution of magnesium in this complex multiphase system. Through the combined use of 16-bit backscattered scanning electron microscopy, multi-channel energy dispersive spectroscopy elemental mapping, and diffraction-limited confocal Raman spectroscopy, we demonstrate a new set of high throughput, multi-spectral, high resolution methods for the large scale characterization of mineralized biological materials. In addition, instrument hardware and data collection protocols can be modified such that several of these measurements can be performed on irregularly shaped samples with complex surface geometries and without the need for extensive sample preparation. Using these approaches, in conjunction with whole animal micro-computed tomography studies, we have been able to spatially resolve micron and sub-micron structural features across macroscopic length scales on entire urchin tooth cross-sections and correlate these complex morphological features with local variability in elemental composition. Copyright © 2015 Elsevier Inc. All rights reserved.
Xia, Hua-Rong; Li, Jia; Peng, Chen; Sun, Wen-Tao; Li, Long-Wei; Peng, Lian-Mao
2014-10-22
The floating growth process of large-scale freestanding TiO2 nanorod films at the gas-liquid interface was investigated. On the basis of the experiments, a self-templated growth scenario was developed to account for the self-assembly process. In the scenario, titanium complexes function not only as the Ti source for the growth of TiO2 but also as a soft template provider for the floating growth. According to the scenario, several new recipes of preparing freestanding TiO2 nanorod films at the gas-liquid interface were developed. The freestanding film was applied to a lithium ion battery as a binder-free and conducting agent-free anode, and good cyclability was obtained. This work may pave a new way to floating and freestanding TiO2 and other semiconductor materials, which has great potential not only in basic science but also in the applications such as materials engineering, Li-ion battery, photocatalyst, dye-sensitized solar cell, and flexible electronics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang Feng; Graduate School of the Chinese Academy of Sciences, Beijing 100039; Jin Guoqiang
2008-07-01
Large-scale ear-like Si{sub 3}N{sub 4} dendrites were prepared by the reaction of SiO{sub 2}/Fe composites and Si powders in N{sub 2} atmosphere. The product was characterized by field emission scanning electron microscopy, X-ray diffraction, and transmission electron microscopy. The results reveal that the product mainly consists of ear-like Si{sub 3}N{sub 4} dendrites with crystal structures, which have a length of several microns and a diameter of 100-200 nm. Nanosized ladder-like Si{sub 3}N{sub 4} was also obtained when changing the Fe content in the SiO{sub 2}/Fe composites. The Si{sub 3}N{sub 4} nanoladders have a length of hundreds nanometers to several micronsmore » and a width of 100-300 nm. The ear-like Si{sub 3}N{sub 4} dendrites are formed from a two-step growth process, the formation of inner stem structures followed by the epitaxial growth of secondary branches.« less
Zhang, Zhi-Hui; Wang, Hu-Jun; Liang, Yun-Hong; Li, Xiu-Juan; Ren, Lu-Quan; Cui, Zhen-Quan; Luo, Cheng
2018-03-01
Superhydrophobic surfaces have great potential for application in self-cleaning and oil/water separation. However, the large-scale practical applications of superhydrophobic coating surfaces are impeded by many factors, such as complicated fabrication processes, the use of fluorinated reagents and noxious organic solvents and poor mechanical stability. Herein, we describe the successful preparation of a fluorine-free multifunctional coating without noxious organic solvents that was brushed, dipped or sprayed onto glass slides and stainless-steel meshes as substrates. The obtained multifunctional superhydrophobic and superoleophilic surfaces (MSHOs) demonstrated self-cleaning abilities even when contaminated with or immersed in oil. The superhydrophobic surfaces were robust and maintained their water repellency after being scratched with a knife or abraded with sandpaper for 50 cycles. In addition, stainless-steel meshes sprayed with the coating quickly separated various oil/water mixtures with a high separation efficiency (>93%). Furthermore, the coated mesh maintained a high separation efficiency above 95% over 20 cycles of separation. This simple and effective strategy will inspire the large-scale fabrication of multifunctional surfaces for practical applications in self-cleaning and oil/water separation.
Zero-reabsorption doped-nanocrystal luminescent solar concentrators.
Erickson, Christian S; Bradshaw, Liam R; McDowall, Stephen; Gilbertson, John D; Gamelin, Daniel R; Patrick, David L
2014-04-22
Optical concentration can lower the cost of solar energy conversion by reducing photovoltaic cell area and increasing photovoltaic efficiency. Luminescent solar concentrators offer an attractive approach to combined spectral and spatial concentration of both specular and diffuse light without tracking, but they have been plagued by luminophore self-absorption losses when employed on practical size scales. Here, we introduce doped semiconductor nanocrystals as a new class of phosphors for use in luminescent solar concentrators. In proof-of-concept experiments, visibly transparent, ultraviolet-selective luminescent solar concentrators have been prepared using colloidal Mn(2+)-doped ZnSe nanocrystals that show no luminescence reabsorption. Optical quantum efficiencies of 37% are measured, yielding a maximum projected energy concentration of ∼6× and flux gain for a-Si photovoltaics of 15.6 in the large-area limit, for the first time bounded not by luminophore self-absorption but by the transparency of the waveguide itself. Future directions in the use of colloidal doped nanocrystals as robust, processable spectrum-shifting phosphors for luminescent solar concentration on the large scales required for practical application of this technology are discussed.
Nam, Moon; Kim, Jeong-Seon; Lim, Seungmo; Park, Chung Youl; Kim, Jeong-Gyu; Choi, Hong-Soo; Lim, Hyoun-Sub; Moon, Jae Sun; Lee, Su-Heon
2014-01-01
A large-scale oligonucleotide (LSON) chip was developed for the detection of the plant viruses with known genetic information. The LSON chip contains two sets of 3,978 probes for 538 species of targets including plant viruses, satellite RNAs and viroids. A hundred forty thousand probes, consisting of isolate-, species- and genus-specific probes respectively, are designed from 20,000 of independent nucleotide sequence of plant viruses. Based on the economic importance, the amount of genome information, and the number of strains and/or isolates, one to fifty-one probes for each target virus are selected and spotted on the chip. The standard and field samples for the analysis of the LSON chip have been prepared and tested by RT-PCR. The probe’s specific and/or nonspecific reaction patterns by LSON chip allow us to diagnose the unidentified viruses. Thus, the LSON chip in this study could be highly useful for the detection of unexpected plant viruses, the monitoring of emerging viruses and the fluctuation of the population of major viruses in each plant. PMID:25288985
Ortega, Humberto E; Teixeira, Eliane de Morais; Rabello, Ana; Higginbotham, Sarah; Cubilla-Ríos, Luis
2014-01-01
Palmarumycin CP18, isolated from an extract of the fermentation broth and mycelium of the Panamanian endophytic fungus Edenia sp., was previously reported with strong and specific activity against Leishmania donovani. Here we report that when the same strain was cultured on different solid media--Harrold Agar, Leonian Agar, Potato dextrose Agar (PDA), Corn Meal Agar, Honey Peptone Agar, and eight vegetables (V8) Agar--in order to determine the optimal conditions for isolation of palmarumycin CP18, no signal for this compound was observed in any of the 1H NMR spectra of fractions obtained from these extracts. However, one extract, prepared from the fungal culture in PDA contained significant amounts of CJ-12,372, a possible biosynthetic precursor of palmarumycin CP18. Edenia sp. was cultivated on a large scale on PDA and CJ-12,372 was converted to palmarumycin CP18 by oxidation of its p-hydroquinone moiety with DDQ in dioxane. Palmarumycin CP18 showed anti-leishmanial activity against L. donovani in a macrophage/amastigote model, with IC50 values of 23.5 microM.
Nano-imprint gold grating as refractive index sensor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kumari, Sudha; Mohapatra, Saswat; Moirangthem, Rakesh S.
Large scale of fabrication of plasmonic nanostructures has been a challenging task due to time consuming process and requirement of expensive nanofabrication tools such as electron beam lithography system, focused ion beam system, and extreme UV photolithography system. Here, we present a cost-effective fabrication technique so called soft nanoimprinting to fabricate nanostructures on the larger sample area. In our fabrication process, a commercially available optical DVD disc was used as a template which was imprinted on a polymer glass substrate to prepare 1D polymer nano-grating. A homemade nanoimprinting setup was used in this fabrication process. Further, a label-free refractive indexmore » sensor was developed by utilizing the properties of surface plasmon resonance (SPR) of a gold coated 1D polymer nano-grating. Refractive index sensing was tested by exposing different solutions of glycerol-water mixture on the surface of gold nano-grating. The calculated bulk refractive index sensitivity was found to be 751nm/RIU. We believed that our proposed SPR sensor could be a promising candidate for developing low-cost refractive index sensor with high sensitivity on a large scale.« less
Scalable 96-well Plate Based iPSC Culture and Production Using a Robotic Liquid Handling System.
Conway, Michael K; Gerger, Michael J; Balay, Erin E; O'Connell, Rachel; Hanson, Seth; Daily, Neil J; Wakatsuki, Tetsuro
2015-05-14
Continued advancement in pluripotent stem cell culture is closing the gap between bench and bedside for using these cells in regenerative medicine, drug discovery and safety testing. In order to produce stem cell derived biopharmaceutics and cells for tissue engineering and transplantation, a cost-effective cell-manufacturing technology is essential. Maintenance of pluripotency and stable performance of cells in downstream applications (e.g., cell differentiation) over time is paramount to large scale cell production. Yet that can be difficult to achieve especially if cells are cultured manually where the operator can introduce significant variability as well as be prohibitively expensive to scale-up. To enable high-throughput, large-scale stem cell production and remove operator influence novel stem cell culture protocols using a bench-top multi-channel liquid handling robot were developed that require minimal technician involvement or experience. With these protocols human induced pluripotent stem cells (iPSCs) were cultured in feeder-free conditions directly from a frozen stock and maintained in 96-well plates. Depending on cell line and desired scale-up rate, the operator can easily determine when to passage based on a series of images showing the optimal colony densities for splitting. Then the necessary reagents are prepared to perform a colony split to new plates without a centrifugation step. After 20 passages (~3 months), two iPSC lines maintained stable karyotypes, expressed stem cell markers, and differentiated into cardiomyocytes with high efficiency. The system can perform subsequent high-throughput screening of new differentiation protocols or genetic manipulation designed for 96-well plates. This technology will reduce the labor and technical burden to produce large numbers of identical stem cells for a myriad of applications.
High-resolution simulation of deep pencil beam surveys - analysis of quasi-periodicity
NASA Astrophysics Data System (ADS)
Weiss, A. G.; Buchert, T.
1993-07-01
We carry out pencil beam constructions in a high-resolution simulation of the large-scale structure of galaxies. The initial density fluctuations are taken to have a truncated power spectrum. All the models have {OMEGA} = 1. As an example we present the results for the case of "Hot-Dark-Matter" (HDM) initial conditions with scale-free n = 1 power index on large scales as a representative of models with sufficient large-scale power. We use an analytic approximation for particle trajectories of a self-gravitating dust continuum and apply a local dynamical biasing of volume elements to identify luminous matter in the model. Using this method, we are able to resolve formally a simulation box of 1200h^-1^ Mpc (e.g. for HDM initial conditions) down to the scale of galactic halos using 2160^3^ particles. We consider this as the minimal resolution necessary for a sensible simulation of deep pencil beam data. Pencil beam probes are taken for a given epoch using the parameters of observed beams. In particular, our analysis concentrates on the detection of a quasi-periodicity in the beam probes using several different methods. The resulting beam ensembles are analyzed statistically using number distributions, pair-count histograms, unnormalized pair-counts, power spectrum analysis and trial-period folding. Periodicities are classified according to their significance level in the power spectrum of the beams. The simulation is designed for application to parameter studies which prepare future observational projects. We find that a large percentage of the beams show quasi- periodicities with periods which cluster at a certain length scale. The periods found range between one and eight times the cutoff length in the initial fluctuation spectrum. At significance levels similar to those of the data of Broadhurst et al. (1990), we find about 15% of the pencil beams to show periodicities, about 30% of which are around the mean separation of rich clusters, while the distribution of scales reaches values of more than 200h^-1^ Mpc. The detection of periodicities larger than the typical void size must not be due to missing of "walls" (like the so called "Great Wall" seen in the CfA catalogue of galaxies), but can be due to different clustering properties of galaxies along the beams.
Thukral, Chandrashekhar; Tewani, Sumeet K; Lake, Adam J; Shiels, Aaron J; Geissler, Kathy; Popejoy, Sara; Stafford, Megan; Vicari, Joseph J
2017-11-03
Current bowel preparations for colonoscopy include a clear liquid diet (CLD) along with consumption of a laxative. This dietary restriction along with large volume bowel preparations are barriers to compliance and willingness among patients in scheduling screening examinations. The aim of our study was to compare the efficacy and tolerability of a low-volume split dose magnesium citrate bowel preparation in patients on a low-residue diet (LRD) with those on a CLD. In this single center, single blinded, randomized controlled trial, patients scheduled for outpatient colonoscopies were assigned to either a CLD or a LRD 1 day before the examination. Both groups received a split dose magnesium citrate preparation. The quality of the preparation was rated using the Boston Bowel Preparation Scale (BBPS). Patient satisfaction and side effects were evaluated using a questionnaire. We were unable to detect a significant difference in the BBPS scores between the LRD and CLD groups (P=0.581). A significantly higher percentage of patients in the LRD group rated the diet as easy compared with the CLD group (P<0.001). Satisfaction scores were significantly higher in the LRD group, compared with the CLD group (P<0.001). The side effect profiles of both arms were similar. There was no significant difference between LRD and CLD in patients using a magnesium citrate bowel preparation for screening and surveillance colonoscopies. Patient satisfaction scores were higher with a LRD compared with a CLD. We believe the LRD should be the recommended diet in patients using a standard bowel preparation for screening and surveillance colonoscopy.
Small-scale multi-axial hybrid simulation of a shear-critical reinforced concrete frame
NASA Astrophysics Data System (ADS)
Sadeghian, Vahid; Kwon, Oh-Sung; Vecchio, Frank
2017-10-01
This study presents a numerical multi-scale simulation framework which is extended to accommodate hybrid simulation (numerical-experimental integration). The framework is enhanced with a standardized data exchange format and connected to a generalized controller interface program which facilitates communication with various types of laboratory equipment and testing configurations. A small-scale experimental program was conducted using a six degree-of-freedom hydraulic testing equipment to verify the proposed framework and provide additional data for small-scale testing of shearcritical reinforced concrete structures. The specimens were tested in a multi-axial hybrid simulation manner under a reversed cyclic loading condition simulating earthquake forces. The physical models were 1/3.23-scale representations of a beam and two columns. A mixed-type modelling technique was employed to analyze the remainder of the structures. The hybrid simulation results were compared against those obtained from a large-scale test and finite element analyses. The study found that if precautions are taken in preparing model materials and if the shear-related mechanisms are accurately considered in the numerical model, small-scale hybrid simulations can adequately simulate the behaviour of shear-critical structures. Although the findings of the study are promising, to draw general conclusions additional test data are required.
Engineering-Scale Demonstration of DuraLith and Ceramicrete Waste Forms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Josephson, Gary B.; Westsik, Joseph H.; Pires, Richard P.
2011-09-23
To support the selection of a waste form for the liquid secondary wastes from the Hanford Waste Immobilization and Treatment Plant, Washington River Protection Solutions (WRPS) has initiated secondary waste form testing on four candidate waste forms. Two of the candidate waste forms have not been developed to scale as the more mature waste forms. This work describes engineering-scale demonstrations conducted on Ceramicrete and DuraLith candidate waste forms. Both candidate waste forms were successfully demonstrated at an engineering scale. A preliminary conceptual design could be prepared for full-scale production of the candidate waste forms. However, both waste forms are stillmore » too immature to support a detailed design. Formulations for each candidate waste form need to be developed so that the material has a longer working time after mixing the liquid and solid constituents together. Formulations optimized based on previous lab studies did not have sufficient working time to support large-scale testing. The engineering-scale testing was successfully completed using modified formulations. Further lab development and parametric studies are needed to optimize formulations with adequate working time and assess the effects of changes in raw materials and process parameters on the final product performance. Studies on effects of mixing intensity on the initial set time of the waste forms are also needed.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu Kai; Zheng Yuhua; Jia Guang
Nano/micro-sized coordination polymer La(1,3,5-BTC)(H{sub 2}O){sub 6} with controllable morphologies have been successfully prepared on a large scale via a simple solution phase method at room temperature. By rationally adjusting the synthetic parameters such as concentration, molar ratio of reactants, surfactant, and solvent, the La(1,3,5-BTC)(H{sub 2}O){sub 6} with 3D flowerlike, wheatearlike, spherical, sheaflike, taillike, bundlelike hierarchical architectures, and 1D nanorods can be selectively prepared. More interestingly, the photoluminescence color of codoped Eu{sup 3+} and Tb{sup 3+} lanthanum 1,3,5-benzenetricarboxylate phosphors can be easily tuned from red, orange, yellow, green-yellow to green by changing co-doping concentration of activator ions, making the material hasmore » potential applications in building minioptoelectronic devices, biomedicine, and color display fields. - Graphical abstract: La(1,3,5-BTC)(H{sub 2}O){sub 6} with 3D flowerlike, wheatearlike, spherical, sheaflike, taillike, bundlelike architectures, and 1D nanorods were selectively prepared; color-tunable photoluminescence from red to green was also realized by co-doping Eu{sup 3+} and Tb{sup 3+}.« less
As-prepared MoS2 quantum dot as a facile fluorescent probe for long-term tracing of live cells
NASA Astrophysics Data System (ADS)
Zhou, Kai; Zhang, Yue; Xia, Zhining; Wei, Weili
2016-07-01
Recently, the newly emerged two-dimensional nanomaterials, layered transition metal dichalcogenide (e.g. MoS2) nanosheets, have drawn tremendous attentions due to their extraordinary electronic and optical properties, and MoS2 quantum dots (MoS2 QDs) with lateral sizes less than 10 nm have been found to be highly luminescent. In the present study, a facile approach for large-scale preparation of MoS2 QDs by Na intercalation reaction without using any toxic organic reagents is proposed. MoS2 QDs were carefully characterized by various techniques including transmission electron microscopy, atomic force microscopy, dynamic light scattering, spectroscopy, in vitro cytotoxicology, and capillary electrophoresis. The as-prepared MoS2 QDs were strongly fluorescent, highly photo-stable, low in cytotoxicity, and readily reactive to thiols. These inherent properties of MoS2 QDs make them excellent fluorescent probes for long-term live cell tracing. The results of live cells imaging indicated that MoS2 QD stained cells remained highly fluorescent after long-term culture, and could be easily traced from other co-cultured cell lines.
Wang, Jie; Tang, Jing; Ding, Bing; Chang, Zhi; Hao, Xiaodong; Takei, Toshiaki; Kobayashi, Naoya; Bando, Yoshio; Zhang, Xiaogang; Yamauchi, Yusuke
2018-04-01
Metal-organic frameworks (MOFs) have become a research hotspot since they have been explored as convenient precursors for preparing various multifunctional nanomaterials. However, the preparation of MOF networks with controllable flake morphology in large scale is not realized yet. Herein, a self-template strategy is developed to prepare MOF networks. In this work, layered double-metal hydroxide (LDH) and other layered metal hydroxides are used not only as a scaffold but also as a self-sacrificed metal source. After capturing the abundant metal cations identically from the LDH by the organic linkers, MOF networks are in situ formed. It is interesting that the MOF network-derived carbon materials retain the flake morphology and exhibit a unique honeycomb-like macroporous structure due to the confined shrinkage of the polyhedral facets. The overall properties of the carbon networks are adjustable according to the tailored metal compositions in LDH and the derived MOFs, which are desirable for target-oriented applications as exemplified by the electrochemical application in supercapacitors. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
An air-stable Na 3SbS 4 superionic conductor prepared by a rapid and economic synthetic procedure
Wang, Hui; Chen, Yan; Hood, Zachary D.; ...
2016-01-01
All-solid-state sodium batteries, using abundant sodium resources and solid electrolyte, hold much promise for safe, low cost, large-scale energy storage. To realize the practical applications of all solid Na-ion batteries at ambient temperature, the solid electrolytes are required to have high ionic conductivity, chemical stability, and ideally, easy preparation. Ceramic electrolytes show higher ionic conductivity than polymers, but they often require extremely stringent synthesis conditions, either high sintering temperature above 1000 C or long-time, low-energy ball milling. Herein, we report a new synthesis route for Na 3SbS 4, a novel Na superionic conductor that needs much lower processing temperature belowmore » 200 C and easy operation. This new solid electrolyte exhibits a remarkable ionic conductivity of 1.05 mS cm -1 at 25 °C and is chemically stable under ambient atmosphere. In conclusion, this synthesis process provides unique insight into the current state-of-the-art solid electrolyte preparation and opens new possibilities for the design of similar materials.« less
NASA Astrophysics Data System (ADS)
Stewart, John
2015-04-01
The amount of time spent on out-of-class activities such as working homework, reading, and studying for examinations is presented for 10 years of an introductory, calculus-based physics class at a large public university. While the class underwent significant change in the 10 years studied, the amount of time invested by students in weeks not containing an in-semester examination was constant and did not vary with the length of the reading or homework assignments. The amount of time spent preparing for examinations did change as the course was modified. The time spent on class assignments, both reading and homework, did not scale linearly with the length of the assignment. The time invested in both reading and homework per length of the assignment decreased as the assignments became longer. The class average time invested in examination preparation did change with the average performance on previous examinations in the same class, with more time spent in preparation for lower previous examination scores (R2 = 0 . 70).
Microwave-assisted synthesis and humidity sensing of nanostructured {alpha}-Fe{sub 2}O{sub 3}
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deshmukh, Rupali G.; Badadhe, Satish S.; Mulla, Imtiaz S.
2009-05-06
Nanocrystalline {alpha}-Fe{sub 2}O{sub 3} has been prepared on a large-scale by a facile microwave-assisted hydrothermal route from a solution of Fe(NO{sub 3}){sub 3}.9H{sub 2}O and pentaerythritol. A systematic study of the morphology, crystallinity and oxidation state of Fe using different characterization techniques, such as transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy was performed. It reveals that nanostructured {alpha}-Fe{sub 2}O{sub 3} comprises bundles of nanorods with a rhombohedral crystalline structure. The individual nanorod has 8-10 nm diameter and {approx}50 nm length. The as-prepared nanostructured {alpha}-Fe{sub 2}O{sub 3} (sensor) gives selective response towards humidity. The sensor shows high sensitivity, fastmore » linear response to change in the humidity with almost 100% reproducibility. The sensor works at room temperature and rejuvenates without heat treatment. The as-prepared nanostructured {alpha}-Fe{sub 2}O{sub 3} appears to be a promising humidity sensing material with the potential for commercialization.« less
NASA Astrophysics Data System (ADS)
Ata-Allah, S. S.; Balagurov, A. M.; Hashhash, A.; Bobrikov, I. A.; Hamdy, Sh.
2016-01-01
The parent NiFe2O4 and Zn/Ga substituted spinel ferrite powders have been prepared by solid state reaction technique. As a typical example, the Ni0.7Zn0.3Fe1.5Ga0.5O4 sample has been prepared by sol-gel auto combustion method with the nano-scale crystallites size. X-ray and Mössbauer studies were carried out for the prepared samples. Structure and microstructure properties were investigated using the time-of-flight HRFD instrument at the IBR-2 pulsed reactor, at a temperatures range 15-473 K. The Rietveld refinement of the neutron diffraction data revealed that all samples possess cubic symmetry corresponding to the space group Fd3m. Cations distribution show that Ni2+ is a complete inverse spinel ion, while Ga3+ equally distributed between the two A and B-sublattices. The level of microstrains in bulk samples was estimated as very small while the size of coherently scattered domains is quite large. For nano-structured sample the domain size is around 120 Å.
Zhao, Xiulan; Yang, Feng; Chen, Junhan; Ding, Li; Liu, Xiyan; Yao, Fengrui; Li, Meihui; Zhang, Daqi; Zhang, Zeyao; Liu, Xu; Yang, Juan; Liu, Kaihui; Li, Yan
2018-04-19
Bimetallic catalysts play important roles in the selective growth of single-walled carbon nanotubes (SWNTs). Using the simple salts (NH4)6W7O24·6H2O and Co(CH3COO)2·4H2O as precursors, tungsten-cobalt catalysts were prepared. The catalysts were composed of W6Co7 intermetallic compounds and tungsten-dispersed cobalt. With the increase of the W/Co ratio in the precursors, the content of W6Co7 was increased. Because the W6Co7 intermetallic compound can enable the chirality specified growth of SWNTs, the selectivity of the resulting SWNTs is improved at a higher W/Co ratio. At a W/Co ratio of 6 : 4 and under optimized chemical vapor deposition conditions, we realized the direct growth of semiconducting SWNTs with the purity of ∼96%, in which ∼62% are (14, 4) tubes. Using salts as precursors to prepare tungsten-cobalt bimetallic catalysts is flexible and convenient. This offers an efficient pathway for the large-scale preparation of chirality enriched semiconducting SWNTs.
Xia, Guobin; Lin, Chunfang; Liu, Songbai
2016-09-01
A large scale isolation and purification of theaflavin (TF) and epigallocatechin (EGC) has been successfully developed by tannase-mediated biotransformation combining high-speed countercurrent chromatography. After tannase hydrolysis of a commercially available theaflavins extract (TE), the content of TF and EGC in tannase-mediated biotransformation product (TBP) achieved approximately 3 times enrichment. SEM studies revealed smooth tannase biotransformation and the possibility of recovery of the tannase. A single 1.5 hours' HSCCC separation for TF and EGC employing a two-phase solvent system could simultaneously produce 180.8 mg of 97.3% purity TF and 87.5 mg of 97.3% purity EGC. However, a preparative HPLC separation of maximum injection volume containing 120 mg TBP prepared 11.2 mg TF of 94.9% purity and 7.7 mg EGC of 89.9% purity. HSCCC separation demonstrated significant advantages over Prep HPLC in terms of sample loading size, separation time, environmental friendly solvent systems, and the production. © 2016 Wiley Periodicals, Inc.
Zhao, Xinzhen; He, Chunju
2015-08-19
On the basis of the excellent fouling resistance of zwitterionic materials, the super antifouling polyvinylidene fluoride (PVDF) membrane was efficiently prepared though one-step sulfonation of PVDF and polyaniline blend membrane in situ. The self-doped sulfonated polyaniline (SPANI) was generated as a novel zwitterionic polymer to improve the antifouling property of PVDF ultrafiltration membrane used in sewage treatment. Surface attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, surface zeta potential, and water contact angle demonstrated the successful fabrication of zwitterionic interface by convenient sulfonation modification. The static adsorption fouling test showed the quantified adsorption mass of bovine serum albumin (BSA) pollutant on the PVDF/SPANI membrane surface decreases to 3(±2) μg/cm(2), and the water flux recovery ratio (FRR) values were no less than 95% for the three model pollutants of BSA, sodium alginate (SA), and humic acid (HA), which were corresponding hydrophobic, hydrophilic, and natural pollutants in sewage, respectively. This Research Article demonstrated the antifouling advantages of zwitterionic SPANI and aimed to provide a simple method for the large scale preparation of zwitterionic antifouling ultrafiltration membranes.
NASA Astrophysics Data System (ADS)
Panda, C. D.; O'Leary, B. R.; West, A. D.; Baron, J.; Hess, P. W.; Hoffman, C.; Kirilov, E.; Overstreet, C. B.; West, E. P.; DeMille, D.; Doyle, J. M.; Gabrielse, G.
2016-05-01
Experimental searches for the electron electric-dipole moment (EDM) probe new physics beyond the standard model. The current best EDM limit was set by the ACME Collaboration [Science 343, 269 (2014), 10.1126/science.1248213], constraining time-reversal symmetry (T ) violating physics at the TeV energy scale. ACME used optical pumping to prepare a coherent superposition of ThO H3Δ1 states that have aligned electron spins. Spin precession due to the molecule's internal electric field was measured to extract the EDM. We report here on an improved method for preparing this spin-aligned state of the electron by using stimulated Raman adiabatic passage (STIRAP). We demonstrate a transfer efficiency of 75 %±5 % , representing a significant gain in signal for a next-generation EDM experiment. We discuss the particularities of implementing STIRAP in systems such as ours, where molecular ensembles with large phase-space distributions are transferred via weak molecular transitions with limited laser power and limited optical access.
Nagachinta, Supakana; Akoh, Casimir C
2013-05-08
Structured lipid (SL) enriched with arachidonic (ARA) and docosahexaenoic (DHA) acids was produced from tripalmitin using Lipozyme TL IM. The effects of acyl donors, that is, free fatty acids vs fatty acid ethyl esters, on the reactions were compared. The highest total incorporation of ARA and DHA was obtained when the reaction continued for 24 h, at a substrate mole ratio of 9, using free fatty acids as acyl donors (acidolysis). The SL prepared by a large-scale acidolysis reaction contained 17.69 ± 0.09% total ARA, 10.75 ± 0.15% total DHA, and 48.53 ± 1.40% sn-2 palmitic acid. SL thermograms exhibited multiple peaks indicating complexity of the triacylglycerol (TAG) distribution. RP-HPLC analysis of SL revealed nine of 26 TAG molecular species that were similar to those of human milk fat. Powdered infant formulas containing the SL were prepared by wet-mixing/spray-drying and dry-blending methods. Formula prepared with microencapsulated SL and the dry-blending method had better oxidative stability and color quality.
Sorochinsky, Alexander E; Aceña, José Luis; Moriwaki, Hiroki; Sato, Tatsunori; Soloshonok, Vadim A
2013-10-01
Alkylations of chiral or achiral Ni(II) complexes of glycine Schiff bases constitute a landmark in the development of practical methodology for asymmetric synthesis of α-amino acids. Straightforward, easy preparation as well as high reactivity of these Ni(II) complexes render them ready available and inexpensive glycine equivalents for preparing a wide variety of α-amino acids, in particular on a relatively large scale. In the case of Ni(II) complexes containing benzylproline moiety as a chiral auxiliary, their alkylation proceeds with high thermodynamically controlled diastereoselectivity. Similar type of Ni(II) complexes derived from alanine can also be used for alkylation providing convenient access to quaternary, α,α-disubstituted α-amino acids. Achiral type of Ni(II) complexes can be prepared from picolinic acid or via recently developed modular approach using simple secondary or primary amines. These Ni(II) complexes can be easily mono/bis-alkylated under homogeneous or phase-transfer catalysis conditions. Origin of diastereo-/enantioselectivity in the alkylations reactions, aspects of practicality, generality and limitations of this methodology is critically discussed.
Critical scaling near the yielding transition in granular media
NASA Astrophysics Data System (ADS)
Clark, Abram H.; Thompson, Jacob D.; Shattuck, Mark D.; Ouellette, Nicholas T.; O'Hern, Corey S.
2018-06-01
We show that the yielding transition in granular media displays second-order critical-point scaling behavior. We carry out discrete element simulations in the low-inertial-number limit for frictionless, purely repulsive spherical grains undergoing simple shear at fixed nondimensional shear stress Σ in two and three spatial dimensions. To find a mechanically stable (MS) packing that can support the applied Σ , isotropically prepared states with size L must undergo a total strain γms(Σ ,L ) . The number density of MS packings (∝γms-1 ) vanishes for Σ >Σc≈0.11 according to a critical scaling form with a length scale ξ ∝|Σ - Σc|-ν , where ν ≈1.7 -1.8 . Above the yield stress (Σ >Σc ), no MS packings that can support Σ exist in the large-system limit L /ξ ≫1 . MS packings generated via shear possess anisotropic force and contact networks, suggesting that Σc is associated with an upper limit in the degree to which these networks can be deformed away from those for isotropic packings.
European Wintertime Windstorms and its Links to Large-Scale Variability Modes
NASA Astrophysics Data System (ADS)
Befort, D. J.; Wild, S.; Walz, M. A.; Knight, J. R.; Lockwood, J. F.; Thornton, H. E.; Hermanson, L.; Bett, P.; Weisheimer, A.; Leckebusch, G. C.
2017-12-01
Winter storms associated with extreme wind speeds and heavy precipitation are the most costly natural hazard in several European countries. Improved understanding and seasonal forecast skill of winter storms will thus help society, policy-makers and (re-) insurance industry to be better prepared for such events. We firstly assess the ability to represent extra-tropical windstorms over the Northern Hemisphere of three seasonal forecast ensemble suites: ECMWF System3, ECMWF System4 and GloSea5. Our results show significant skill for inter-annual variability of windstorm frequency over parts of Europe in two of these forecast suites (ECMWF-S4 and GloSea5) indicating the potential use of current seasonal forecast systems. In a regression model we further derive windstorm variability using the forecasted NAO from the seasonal model suites thus estimating the suitability of the NAO as the only predictor. We find that the NAO as the main large-scale mode over Europe can explain some of the achieved skill and is therefore an important source of variability in the seasonal models. However, our results show that the regression model fails to reproduce the skill level of the directly forecast windstorm frequency over large areas of central Europe. This suggests that the seasonal models also capture other sources of variability/predictability of windstorms than the NAO. In order to investigate which other large-scale variability modes steer the interannual variability of windstorms we develop a statistical model using a Poisson GLM. We find that the Scandinavian Pattern (SCA) in fact explains a larger amount of variability for Central Europe during the 20th century than the NAO. This statistical model is able to skilfully reproduce the interannual variability of windstorm frequency especially for the British Isles and Central Europe with correlations up to 0.8.
NASA Astrophysics Data System (ADS)
Zhang, Saifei; Zeng, Weidong; Gao, Xiongxiong; Zhao, Xingdong; Li, Siqing
2017-10-01
The present study investigates the mechanical properties of large-scale beta-processed Ti-17 forgings because of the increasing interest in beta thermal-mechanical processing method for fabricating compressor disks or blisks in aero-engines due to its advantage in damage tolerance performance. Three Ti-17 disks with different weights of 57, 250 and 400 kg were prepared by beta processing techniques firstly for comparative study. The results reveal a significant `size effect' in beta-processed Ti-17 disks, i.e., dependences of high cycle fatigue, tensile properties and fracture toughness of beta-processed Ti-17 disks on disk size (or weight). With increasing disk weight from 57 to 400 kg, the fatigue limit (fatigue strength at 107 cycles, R = -1) was reduced from 583 to 495 MPa, tensile yield strength dropped from 1073 to 1030 MPa, while fracture toughness ( K IC) rose from 70.9 to 95.5 MPaṡm1/2. Quantitative metallography analysis shows that the `size effect' of mechanical properties can be attributed to evident differences between microstructures of the three disk forgings. With increasing disk size, nearly all microstructural components in the basket-weave microstructure, including prior β grain, α layers at β grain boundaries (GB- α) and α lamellas at the interior of the grains, get coarsened to different degrees. Further, the microstructural difference between the beta-processed disks is proved to be the consequence of longer pre-forging soaking time and lower post-forging cooling rate for large disks than small ones. Finally, suggestions are made from the perspective of microstructural control on how to improve mechanical properties of large-scale beta-processed Ti-17 forgings.
Collective synthesis of natural products by means of organocascade catalysis.
Jones, Spencer B; Simmons, Bryon; Mastracchio, Anthony; MacMillan, David W C
2011-07-13
Organic chemists are now able to synthesize small quantities of almost any known natural product, given sufficient time, resources and effort. However, translation of the academic successes in total synthesis to the large-scale construction of complex natural products and the development of large collections of biologically relevant molecules present significant challenges to synthetic chemists. Here we show that the application of two nature-inspired techniques, namely organocascade catalysis and collective natural product synthesis, can facilitate the preparation of useful quantities of a range of structurally diverse natural products from a common molecular scaffold. The power of this concept has been demonstrated through the expedient, asymmetric total syntheses of six well-known alkaloid natural products: strychnine, aspidospermidine, vincadifformine, akuammicine, kopsanone and kopsinine. ©2011 Macmillan Publishers Limited. All rights reserved
Cost-effective fabrication of thermal- and chemical-stable ZIF-9 nanocrystals at ammonia atmosphere
NASA Astrophysics Data System (ADS)
Ebrahimi, Arash; Mansournia, Mohammadreza
2017-12-01
In this study, room temperature synthesis of zeolitic imidazolate framework-9 (ZIF-9) nanocrystals is reported for the first time at ammonia atmosphere in the absence of any organic additive. High thermal stability of the as-fabricated ZIF-9 up to 300 °C is illustrated by TG and XRD data. Also, the chemical resistance of product to harsh and severe solvothermal conditions introduces it to be an objective as potential material in many applications. Besides, the modest microporosity of the as-obtained ZIF-9 materials attracts more attentions for further investigation compared to those fabricated in organic solvents. By and large, the represented low-cost and room temperature synthetic method can be applicable in the large scale preparation of ZIF-9 for potentially practical utilization.
Molecular-Scale Hybrid Membranes Derived from Metal-Organic Polyhedra for Gas Separation.
Liu, Xinlei; Wang, Xuerui; Bavykina, Anastasiya V; Chu, Liangyong; Shan, Meixia; Sabetghadam, Anahid; Miro, Hozanna; Kapteijn, Freek; Gascon, Jorge
2018-06-13
The preparation and the performance of mixed matrix membranes based on metal-organic polyhedra (MOPs) are reported. MOP fillers can be dispersed as discrete molecular units (average 9 nm in diameter) when low filler cargos are used. In spite of the low doping amount (1.6 wt %), a large performance enhancement in permeability, aging resistance, and selectivity can be achieved. We rationalize this effect on the basis of the large surface to volume ratio of the filler, which leads to excellent dispersion at low concentrations and thus alters polymer packing. Although membranes based only on the polymer component age quickly with time, the performance of the resulting MOP-containing membranes meets the commercial target for postcombustion CO 2 capture for more than 100 days.
Mosaic construction, processing, and review of very large electron micrograph composites
NASA Astrophysics Data System (ADS)
Vogt, Robert C., III; Trenkle, John M.; Harmon, Laurel A.
1996-11-01
A system of programs is described for acquisition, mosaicking, cueing and interactive review of large-scale transmission electron micrograph composite images. This work was carried out as part of a final-phase clinical analysis study of a drug for the treatment of diabetic peripheral neuropathy. MOre than 500 nerve biopsy samples were prepared, digitally imaged, processed, and reviewed. For a given sample, typically 1000 or more 1.5 megabyte frames were acquired, for a total of between 1 and 2 gigabytes of data per sample. These frames were then automatically registered and mosaicked together into a single virtual image composite, which was subsequently used to perform automatic cueing of axons and axon clusters, as well as review and marking by qualified neuroanatomists. Statistics derived from the review process were used to evaluate the efficacy of the drug in promoting regeneration of myelinated nerve fibers. This effort demonstrates a new, entirely digital capability for doing large-scale electron micrograph studies, in which all of the relevant specimen data can be included at high magnification, as opposed to simply taking a random sample of discrete locations. It opens up the possibility of a new era in electron microscopy--one which broadens the scope of questions that this imaging modality can be used to answer.
Reducing the Consequences of a Nuclear Detonation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Buddemeier, B R
2007-11-09
The 2002 National Strategy to Combat Weapons of Mass Destruction states that 'the United States must be prepared to respond to the use of WMD against our citizens, our military forces, and those of friends and allies'. Scenario No.1 of the 15 Department of Homeland Security national planning scenarios is an improvised nuclear detonation in the national capitol region. An effective response involves managing large-scale incident response, mass casualty, mass evacuation, and mass decontamination issues. Preparedness planning activities based on this scenario provided difficult challenges in time critical decision making and managing a large number of casualties within the hazardmore » area. Perhaps even more challenging is the need to coordinate a large scale response across multiple jurisdictions and effectively responding with limited infrastructure and resources. Federal response planning continues to make improvements in coordination and recommending protective actions, but much work remains. The most critical life-saving activity depends on actions taken in the first few minutes and hours of an event. The most effective way to reduce the enormous national and international social and economic disruptions from a domestic nuclear explosion is through planning and rapid action, from the individual to the federal response. Anticipating response resources for survivors based on predicted types and distributions of injuries needs to be addressed.« less
Zhang, Sheng; Shao, Yuyan; Liao, Honggang; Engelhard, Mark H; Yin, Geping; Lin, Yuehe
2011-03-22
Here we report that poly(diallyldimethylammonium chloride) (PDDA) acts as both a reducing agent and a stabilizer to prepare soluble graphene nanosheets from graphite oxide. The results of transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, atomic force microscopy, and Fourier transform infrared indicated that graphite oxide was successfully reduced to graphene nanosheets which exhibited single-layer structure and high dispersion in various solvents. The reaction mechanism for PDDA-induced reduction of exfoliated graphite oxide was proposed. Furthermore, PDDA facilitated the in situ growth of highly dispersed Pt nanoparticles on the surface of graphene nanosheets to form Pt/graphene nanocomposites, which exhibited excellent catalytic activity toward formic acid oxidation. This work presents a facile and environmentally friendly approach to the synthesis of graphene nanosheets and opens up a new possibility for preparing graphene and graphene-based nanomaterials for large-scale applications.
An improved soft-chemistry approach to the preparation of spinel powders
NASA Astrophysics Data System (ADS)
Cook, Ronald
2007-04-01
Spinel powders for the production of transparent polycrystalline ceramic windows have been produced using a number of traditional ceramic and sol-gel methods. We have demonstrated that magnesium aluminate spinel powders produced from the reaction of organo-magnesium compounds with surface modified boehmite precursors can be used to produce high quality transparent spinel parts. In previous work, the spinel powders were prepared by the reaction of surface-modified boehmite nanoparticles with magnesium acetylacetonate. While the magnesium acetylacetonate can produce small quantities of high quality spinel powders, it use for large scale production of spinel powders is problematic. Through a thermodynamic analysis we have identified a new high-purity, low-cost, low-toxicity organomagnesium compound that reacts the with surface modified boehmite nanoparticles to produce a spinel precursor. The magnesium doped precursor readily transforms into pure phase spinel at temperature between 900°C and 1200°C.
Production of footbridge with double curvature made of UHPC
NASA Astrophysics Data System (ADS)
Kolísko, J.; Čítek, D.; Tej, P.; Rydval, M.
2017-09-01
This article present a mix design, preparation and production of thin-walled footbridge made from UHPFRC. In this case an experimental pedestrian bridge was design and prepared. Bridge with span of 10 m and the clear width of 1.50 m designed as single-span bridge. Optimization of UHPFRC matrix and parameters of this material leads to the design of very thin structures. Total thickness of shell structure 30 - 45 mm. Bridge was cast as a prefabricated element in one piece. Self-compacting character of UHPFRC with high flowability allows the production of the final structure. Extensive research was done before production of footbridge. Experimental reached data were compared with extensive numerical analysis and the final design of structure and UHPFRC matrix were optimized in many details. Two versions of large scale mock-ups were casted and tested. According to the complexity of whole experiment a casting technology and production of formwork were tested and optimized many times.
Yu, Daoyong; Huang, Guihong; Xu, Fengxi; Wang, Mengfei; Liu, Shuang; Huang, Fang
2014-06-01
Surfactants play important roles in the preparation, structural, and functional research of membrane proteins, and solubilizing and isolating membrane protein, while keeping their structural integrity and activity intact is complicated. The commercial n-Dodecyl-β-D-maltoside (DDM) and Triton X-100 (TX) were used as solubilizers to extract and purify trimeric photosystem I (PSI) complex, an important photosynthetic membrane protein complex attracting broad interests. With an optimized procedure, TX can be used as an effective surfactant to isolate and purify PSI, as a replace of the much more expensive DDM. A mechanism was proposed to interpret the solubilization process at surfactant concentrations lower than the critical solubilization concentration. PSI-TX and PSI-DDM had identical polypeptide bands, pigment compositions, oxygen consumption, and photocurrent activities. This provides an alternative procedure and paves a way for economical and large-scale trimeric PSI preparation.
Ultrasound exfoliation of inorganic analogues of graphene
2014-01-01
High-intensity ultrasound exfoliation of a bulk-layered material is an attractive route for large-scale preparation of monolayers. The monolayer slices could potentially be prepared with a high yield (up to 100%) in a few minutes. Exfoliation of natural minerals (such as tungstenite and molybdenite) or bulk synthetic materials (including hexagonal boron nitride (h-BN), hexagonal boron carbon nitride (h-BCN), and graphitic carbon nitride (g-C3N4)) in liquids leads to the breakdown of the 3D graphitic structure into a 2D structure; the efficiency of this process is highly dependent upon the physical effects of the ultrasound. Atomic force microscopy (AFM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) were employed to verify the quality of the exfoliation. Herein, this new method of exfoliation with ultrasound assistance for application to mono- and bilayered materials in hydrophobic and hydrophilic environments is presented. PMID:24708572
Ultrasound exfoliation of inorganic analogues of graphene.
Stengl, Václav; Henych, Jiří; Slušná, Michaela; Ecorchard, Petra
2014-04-05
High-intensity ultrasound exfoliation of a bulk-layered material is an attractive route for large-scale preparation of monolayers. The monolayer slices could potentially be prepared with a high yield (up to 100%) in a few minutes. Exfoliation of natural minerals (such as tungstenite and molybdenite) or bulk synthetic materials (including hexagonal boron nitride (h-BN), hexagonal boron carbon nitride (h-BCN), and graphitic carbon nitride (g-C3N4)) in liquids leads to the breakdown of the 3D graphitic structure into a 2D structure; the efficiency of this process is highly dependent upon the physical effects of the ultrasound. Atomic force microscopy (AFM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) were employed to verify the quality of the exfoliation. Herein, this new method of exfoliation with ultrasound assistance for application to mono- and bilayered materials in hydrophobic and hydrophilic environments is presented.
Rein, Benjamin A; McNeil, Daniel W; Hayes, Allison R; Hawkins, T Anne; Ng, H Mei; Yura, Catherine A
2018-07-01
Training programs exist that prepare college students, faculty, and staff to identify and support students potentially at risk for suicide. Kognito is an online program that trains users through simulated interactions with virtual humans. This study evaluated Kognito's effectiveness in preparing users to intervene with at-risk students. Training was completed by 2,727 university students, faculty, and staff from April, 2014 through September, 2015. Voluntary and mandatory participants at a land-grant university completed Kognito modules designed for higher education, along with pre- and post-assessments. All modules produced significant gains in reported Preparedness, Likelihood, and Self-Efficacy in intervening with troubled students. Despite initial disparities in reported abilities, after training participants reported being similarly capable of assisting at-risk students, including LGBTQ and veteran students. Kognito training appears to be effective, on a large scale, in educating users to act in a facilitative role for at-risk college students.
The politics of disaster - Nicaragua.
Bommer, J
1985-12-01
The occurrence of natural disasters, such as floods and earthquakes, are, in themselves, beyond oar control. However, careful preparation before such events, and the correct management of the problem once it occurs, can both lead to major redaction of the suffering involved. Disaster preparation and emergency planning are both inextricably linked to politics and economics, both on a national and an international scale. Disasters themselves raise a number of issues of a political or economic nature, and die response to a natural disaster both in the short and the long term is largely determined by the political relations within a country, and between that country and the international community. This paper examines these issues by taking the examples of the earthquake of Managua, Nicaragua in 1972 and the flooding that occurred in Nicaragua in 1982. These two natural disasters occurred under different administrations in Nicaragua, and tills allows some interesting comparisons.
Microwave Absorption Properties of Iron Nanoparticles Prepared by Ball-Milling
NASA Astrophysics Data System (ADS)
Chu, Xuan T. A.; Ta, Bach N.; Ngo, Le T. H.; Do, Manh H.; Nguyen, Phuc X.; Nam, Dao N. H.
2016-05-01
A nanopowder of iron was prepared using a high-energy ball milling method, which is capable of producing nanoparticles at a reasonably larger scale compared to conventional chemical methods. Analyses using x-ray diffraction and magnetic measurements indicate that the iron nanoparticles are a single phase of a body-centered cubic structure and have quite stable magnetic characteristics in the air. The iron nanoparticles were then mixed with paraffin and pressed into flat square plates for free-space microwave transmission and reflection measurements in the 4-8 GHz range. Without an Al backing plate, the Fe nanoparticles seem to only weakly absorb microwave radiation. The reflected signal S 11 drops to zero and a very large negative value of reflection loss ( RL) are observed for Al-backed samples, suggesting the existence of a phase matching resonance near frequency f ˜ 6 GHz.
NASA Astrophysics Data System (ADS)
Meng, Nannan; Zhou, Yifeng; Nie, Wangyan; Chen, Pengpeng
2016-08-01
The cadmium sulfide nanoparticle-reduced graphene oxide (CdS/RGO) nanocomposite with intimate nano-interfacial contact was successfully prepared via a facile condensation process in dilute dimethylformamide (DMF) aqueous solution. Numerous CdS nanoparticles featuring a size of around 10 nm were homogeneously anchored on 2D nanosheets. During the formation of CdS/RGO nanocomposite, graphene oxide (GO) was transformed into RGO simultaneously. The solar-driven degradation of Rhodamine B (RhB) was conducted to detect the activity of the as-prepared CdS/RGO nanocomposite. Significantly, the photocatalytic activity of CdS/RGO nanocomposite was almost three times higher than that of pure CdS. The charge transfer and photogenerated active hydroxyl radicals (ṡOH) were investigated to study the mechanism of excellent photocatalytic property. The synthetic method provided a valuable opportunity to fabricate large-scale novel graphene-based materials with superior catalytic activity.
Evaluation of EREP techniques for geological mapping. [southern Pyrenees and Ebro basin in Spain
NASA Technical Reports Server (NTRS)
Vandermeermohr, H. E. C.; Srivastava, G. S. (Principal Investigator)
1975-01-01
The author has identified the following significant results. Skylab photographs may be successfully utilized for preparing a reconnaissance geological map in the areas where no maps or semi-detailed maps exist. Large coverage of area and regional perspective from Skylab photographs can help better coordination in regional mapping. It is possible to delineate major structural trends and other features like mega-lineaments, geofractures, and faults, which have evaded their detection by conventional methods. The photointerpretability is better in areas dominated by sedimentary rocks. Rock units of smaller extent and having poor geomorphic expressions are difficult to map. Demarcation of quaternary river alluvium can be made with better precision and ease with the Skylab photographs. Stereoscopic viewing greatly helps in interpretation of area structures. Skylab photographs are not good for preparing geological maps larger than 1:270,000 scale.
Deterministically Entangling Two Remote Atomic Ensembles via Light-Atom Mixed Entanglement Swapping
Liu, Yanhong; Yan, Zhihui; Jia, Xiaojun; Xie, Changde
2016-01-01
Entanglement of two distant macroscopic objects is a key element for implementing large-scale quantum networks consisting of quantum channels and quantum nodes. Entanglement swapping can entangle two spatially separated quantum systems without direct interaction. Here we propose a scheme of deterministically entangling two remote atomic ensembles via continuous-variable entanglement swapping between two independent quantum systems involving light and atoms. Each of two stationary atomic ensembles placed at two remote nodes in a quantum network is prepared to a mixed entangled state of light and atoms respectively. Then, the entanglement swapping is unconditionally implemented between the two prepared quantum systems by means of the balanced homodyne detection of light and the feedback of the measured results. Finally, the established entanglement between two macroscopic atomic ensembles is verified by the inseparability criterion of correlation variances between two anti-Stokes optical beams respectively coming from the two atomic ensembles. PMID:27165122
NASA Technical Reports Server (NTRS)
Li, Tao; Glushakova, Svetlana; Zimmerberg, Joshua
2003-01-01
Plasmodium falciparum replicates poorly in erythrocyte densities greater than a hematocrit of 20%. A new method to culture the major malaria parasite was developed by using a hollow fiber bioreactor that preserves healthy erythrocytes at hematocrit up to 100%. P. falciparum replicated equally well at all densities studied. This method proved advantageous for large-scale preparation of parasitized erythrocytes (and potentially immunogens thereof), because high yields ( approximately 10(10) in 4 days) could be prepared with less cost and labor. Concomitantly, secreted proteins were concentrated by molecular sieving during culture, perhaps contributing to the parasitemic limit of 8%-12% with the 3D7 strain. The finding that P. falciparum can replicate at packed erythrocyte densities suggests that this system may be useful for study of the pathogenesis of fatal cerebral malaria, of which one feature is densely packed blood cells in brain microvasculature.
Juliano, Claudia; Manconi, Paola; Cossu, Massimo
2016-09-01
Perna canaliculus is a nutritional supplement recently studied and highly recommended for its anti-inflammatory effects in both animals and humans. In this study, the physicochemical properties, the microbiological quality, the total lipid content and fatty acids composition of three commercial samples of Perna powder were determined. Subsequently, three simple formulations of extemporaneous oral pastes containing Perna were prepared and designed for veterinary use. Their microbiological stability was assessed after 1-month storage at either room temperature or 35 °C. The results demonstrated that commercial Perna samples lack homogeneity, in regard to some technological properties and fatty acid composition; therefore, a preliminary characterisation of commercial Perna samples is recommended to assure the quality of formulations containing this nutritional supplement. Oral paste formulations are easy and simple to prepare and show good physical and microbiological stability, suggesting their large-scale production.
Ju, Yanming; Meng, Yuan; Wei, Yingjin; Bian, Xiaofei; Pang, Qiang; Gao, Yu; Du, Fei; Liu, Bingbing; Chen, Gang
2016-12-12
The demand for large-scale and safe energy storage is increasing rapidly due to the strong push for smartphones and electric vehicles. As a result, Li + /Mg 2+ hybrid-ion batteries (LMIBs) combining a dendrite-free deposition of Mg anode and Li + intercalation cathode have attracted considerable attention. Here, a LMIB with hydrothermal-prepared MoS 2 nano flowers as cathode material was prepared. The battery showed remarkable electrochemical properties with a large discharge capacity (243 mAh g -1 at the 0.1 C rate), excellent rate capability (108 mAh g -1 at the 5 C rate), and long cycle life (87.2 % capacity retention after 2300 cycles). Electrochemical analysis showed that the reactions occurring in the battery cell involved Mg stripping/plating at the anode side and Li + intercalation at the cathode side with a small contribution from Mg 2+ adsorption. The excellent electrochemical performance and extremely safe cell system show promise for its use in practical applications. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Development, fabrication and test of a high purity silica heat shield
NASA Technical Reports Server (NTRS)
Rusert, E. L.; Drennan, D. N.; Biggs, M. S.
1978-01-01
A highly reflective hyperpure ( 25 ppm ion impurities) slip cast fused silica heat shield material developed for planetary entry probes was successfully scaled up. Process development activities for slip casting large parts included green strength improvements, casting slip preparation, aggregate casting, strength, reflectance, and subscale fabrication. Successful fabrication of a one-half scale Saturn probe (shape and size) heat shield was accomplished while maintaining the silica high purity and reflectance through the scale-up process. However, stress analysis of this original aggregate slip cast material indicated a small margin of safety (MS. = +4%) using a factor of safety of 1.25. An alternate hyperpure material formulation to increase the strength and toughness for a greater safety margin was evaluated. The alternate material incorporates short hyperpure silica fibers into the casting slip. The best formulation evaluated has a 50% by weight fiber addition resulting in an 80% increase in flexural strength and a 170% increase in toughness over the original aggregate slip cast materials with comparable reflectance.
Data for Room Fire Model Comparisons
Peacock, Richard D.; Davis, Sanford; Babrauskas, Vytenis
1991-01-01
With the development of models to predict fire growth and spread in buildings, there has been a concomitant evolution in the measurement and analysis of experimental data in real-scale fires. This report presents the types of analyses that can be used to examine large-scale room fire test data to prepare the data for comparison with zone-based fire models. Five sets of experimental data which can be used to test the limits of a typical two-zone fire model are detailed. A standard set of nomenclature describing the geometry of the building and the quantities measured in each experiment is presented. Availability of ancillary data (such as smaller-scale test results) is included. These descriptions, along with the data (available in computer-readable form) should allow comparisons between the experiment and model predictions. The base of experimental data ranges in complexity from one room tests with individual furniture items to a series of tests conducted in a multiple story hotel equipped with a zoned smoke control system. PMID:28184121
Data for Room Fire Model Comparisons.
Peacock, Richard D; Davis, Sanford; Babrauskas, Vytenis
1991-01-01
With the development of models to predict fire growth and spread in buildings, there has been a concomitant evolution in the measurement and analysis of experimental data in real-scale fires. This report presents the types of analyses that can be used to examine large-scale room fire test data to prepare the data for comparison with zone-based fire models. Five sets of experimental data which can be used to test the limits of a typical two-zone fire model are detailed. A standard set of nomenclature describing the geometry of the building and the quantities measured in each experiment is presented. Availability of ancillary data (such as smaller-scale test results) is included. These descriptions, along with the data (available in computer-readable form) should allow comparisons between the experiment and model predictions. The base of experimental data ranges in complexity from one room tests with individual furniture items to a series of tests conducted in a multiple story hotel equipped with a zoned smoke control system.
NASA Astrophysics Data System (ADS)
Lee, R. J.; Forbes, J. W.; Tasker, D. G.; Orme, R. S.
2009-12-01
The Modified Gap Test was used to quantify different levels of partial reaction for various input stresses. This test configuration has been historically useful in highlighting thresholds for first reaction, sustained ignition, and detonation. Two different HMX based compositions were studied; a cast-cured composition with 87% HMX and a pressed composition with 92% HMX. Each explosive was prepared from large industrially produced batches consisting of different unreactive polymeric binder systems. Short samples (50.8 mm in diameter and 12.7 mm thick) were shock loaded using the standard large-scale gap test donor system. Product-cloud blow-off velocities at the opposite end of the sample were measured using a high-speed digital-camera. Velocity versus input pres sure plots provided changes in reactivity that had developed by the 12.7 mm run distance. Results appear consistent for the lower input stresses. In contrast, the results varied widely in a range of input stresses around the transition to detonation in both explosives. These results indicate that both explosives are subject to large variation in blow-off velocity in a range of input stresses near the threshold for prompt detonation. This is explained by localized variations of HMX particle size and density in industrially prepared samples. Approved for public release, Distribution unlimited, IHDIV Log No. 09-108.
Sumboja, Afriyanti; An, Tao; Goh, Hai Yang; Lübke, Mechthild; Howard, Dougal Peter; Xu, Yijie; Handoko, Albertus Denny; Zong, Yun; Liu, Zhaolin
2018-05-09
Catalysts for hydrogen evolution reaction are in demand to realize the efficient conversion of hydrogen via water electrolysis. In this work, cobalt phosphides were prepared using a one-step, scalable, and direct gas-solid phosphidation of commercially available cobalt salts. It was found that the effectiveness of the phosphidation reaction was closely related to the state of cobalt precursors at the reaction temperature. For instance, a high yield of cobalt phosphides obtained from the phosphidation of cobalt(II) acetate was related to the good stability of cobalt salt at the phosphidation temperature. On the other hand, easily oxidizable salts (e.g., cobalt(II) acetylacetonate) tended to produce a low amount of cobalt phosphides and a large content of metallic cobalt. The as-synthesized cobalt phosphides were in nanostructures with large catalytic surface areas. The catalyst prepared from phosphidation of cobalt(II) acetate exhibited an improved catalytic activity as compared to its counterpart derived from phosphidation of cobalt(II) acetylacetonate, showing an overpotential of 160 and 175 mV in acidic and alkaline electrolytes, respectively. Both catalysts also displayed an enhanced long-term stability, especially in the alkaline electrolyte. This study illustrates the direct phosphidation behavior of cobalt salts, which serve as a good vantage point in realizing the large-scale synthesis of transition-metal phosphides for high-performance electrocatalysts.
YAlO3:Ce3+ powders: Synthesis, characterization, thermoluminescence and optical studies
NASA Astrophysics Data System (ADS)
Parganiha, Yogita; Kaur, Jagjeet; Dubey, Vikas; Shrivastava, Ravi
2015-09-01
Yttrium aluminum perovskite (YAP) is a promising high temperature ceramic material, known for its mechanical, structural and optical properties. YAP's also known as an ideal host material for solid-state lasers and phosphors. In this work, Ce3+ doped YAlO3 phosphors were synthesized by solid state reaction method, which is very suitable technique for large scale production. A prepared phosphor was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Photoluminescence spectra and Thermoluminescence (TL) glow curve study. The starting reagents used for sample preparation are Y2O3, Al2O3 and CeO2, boric acid used as a flux. Ratio of Y:Al was 1:1 which shows perovskite structure confirmed by the X-ray diffraction (XRD) study. The entire prepared sample was studied by PL excitation and emission spectra. Prominent peak at 446 nm (blue emission) which shows broad emission spectra of photoluminescence. It proves that prepared phosphor can act as a single host for blue emission of light and can be used for display applications. Commission Internationale de I'Eclairage (CIE) techniques proves the blue emission of light (x = .148, y = .117). TL glow curve analysis of prepared phosphor shows the prominent peak at 189 °C for the variable UV exposure time and high temperature peak shows the more stability and less fading in the prepared phosphor. Kinetic data of prepared phosphor were evaluated by peak shape method for variable UV exposure time (5-25 min).
NASA Astrophysics Data System (ADS)
Duro, Javier; Iglesias, Rubén; Blanco, Pablo; Albiol, David; Koudogbo, Fifamè
2015-04-01
The Wide Area Product (WAP) is a new interferometric product developed to provide measurement over large regions. Persistent Scatterers Interferometry (PSI) has largely proved their robust and precise performance in measuring ground surface deformation in different application domains. In this context, however, the accurate displacement estimation over large-scale areas (more than 10.000 km2) characterized by low magnitude motion gradients (3-5 mm/year), such as the ones induced by inter-seismic or Earth tidal effects, still remains an open issue. The main reason for that is the inclusion of low quality and more distant persistent scatterers in order to bridge low-quality areas, such as water bodies, crop areas and forested regions. This fact yields to spatial propagation errors on PSI integration process, poor estimation and compensation of the Atmospheric Phase Screen (APS) and the difficult to face residual long-wavelength phase patterns originated by orbit state vectors inaccuracies. Research work for generating a Wide Area Product of ground motion in preparation for the Sentinel-1 mission has been conducted in the last stages of Terrafirma as well as in other research programs. These developments propose technological updates for keeping the precision over large scale PSI analysis. Some of the updates are based on the use of external information, like meteorological models, and the employment of GNSS data for an improved calibration of large measurements. Usually, covering wide regions implies the processing over areas with a land use which is chiefly focused on livestock, horticulture, urbanization and forest. This represents an important challenge for providing continuous InSAR measurements and the application of advanced phase filtering strategies to enhance the coherence. The advanced PSI processing has been performed out over several areas, allowing a large scale analysis of tectonic patterns, and motion caused by multi-hazards as volcanic, landslide and flood. Several examples of the application of the PSI WAP to wide regions for measuring ground displacements related to different types of hazards, natural and human induced will be presented. The InSAR processing approach to measure accurate movements at local and large scales for allowing multi-hazard interpretation studies will also be discussed. The test areas will show deformations related to active faults systems, landslides in mountains slopes, ground compaction over underneath aquifers and movements in volcanic areas.
Mlynek, Georg; Lehner, Anita; Neuhold, Jana; Leeb, Sarah; Kostan, Julius; Charnagalov, Alexej; Stolt-Bergner, Peggy; Djinović-Carugo, Kristina; Pinotsis, Nikos
2014-06-01
Expression in Escherichia coli represents the simplest and most cost effective means for the production of recombinant proteins. This is a routine task in structural biology and biochemistry where milligrams of the target protein are required in high purity and monodispersity. To achieve these criteria, the user often needs to screen several constructs in different expression and purification conditions in parallel. We describe a pipeline, implemented in the Center for Optimized Structural Studies, that enables the systematic screening of expression and purification conditions for recombinant proteins and relies on a series of logical decisions. We first use bioinformatics tools to design a series of protein fragments, which we clone in parallel, and subsequently screen in small scale for optimal expression and purification conditions. Based on a scoring system that assesses soluble expression, we then select the top ranking targets for large-scale purification. In the establishment of our pipeline, emphasis was put on streamlining the processes such that it can be easily but not necessarily automatized. In a typical run of about 2 weeks, we are able to prepare and perform small-scale expression screens for 20-100 different constructs followed by large-scale purification of at least 4-6 proteins. The major advantage of our approach is its flexibility, which allows for easy adoption, either partially or entirely, by any average hypothesis driven laboratory in a manual or robot-assisted manner.
Consumers' convenience orientation towards meal preparation: conceptualization and measurement.
Candel, M
2001-02-01
Consumer researchers consider convenience orientation towards meal preparation to be a relevant construct for understanding consumer behavior towards foods. This study set out to conceptualize this construct and to develop a scale that measures it. As examined in two different samples of meal preparers, the resulting scale is reliable, satisfies a unifactorial structure and has satisfactory convergent validity. The scale's nomological validity is supported in that it conforms to expectations regarding various psychographic constructs and various food-related behaviors. Convenience orientation was found to be negatively related to cooking enjoyment, involvement with food products and variety seeking, and to be positively related to role overload. The analyses also suggest that the lack of relation between the meal preparer's working status and convenience food consumption, as found in many studies, is due to convenience food not offering enough preparation convenience. Consuming take-away meals and eating in restaurants appear to satisfy the consumer's need for convenience more adequately. Copyright 2001 Academic Press.
Zhang, J; Suflita, M; Fiaschetti, C M; Li, G; Li, L; Zhang, F; Dordick, J S; Linhardt, R J
2015-01-01
One of six heparin biosynthetic enzymes, cloned and expressed in Escherichia coli as a soluble fusion protein, requires large-scale preparation for use in the chemoenzymatic synthesis of heparin, an important anticoagulant drug. The 6-O-sulfotransferase isoform-3 (6-OST-3) can be conveniently prepared at mg/L levels in the laboratory by culturing E. coli on Luria-Bertani medium in shake flasks and inducing with isopropyl β-D-1-thiogalactopyranoside at an optical density of 0·6-0·8. The production of larger amounts of 6-OST-3 required fed-batch cultivation of E. coli in a stirred tank fermenter on medium containing an inexpensive carbon source, such as glucose or glycerol. The cultivation of E. coli on various carbon sources under different feeding schedules and induction strategies was examined. Conditions were established giving yields (5-20 mg g-cell-dry weight(-1)) of active 6-OST-3 with excellent productivity (2-5 mg l(-1) h(-1)). The production of 6-OST-3 in a fed-batch fermentation on an inexpensive carbon source has been demonstrated. The ability to scale-up the production of heparin biosynthetic enzymes, such as 6-OST-3, is critical for scaling-up the chemoenzymatic synthesis of heparin. The success of this project may someday lead to a commercially viable bioengineered heparin to replace the animal-sourced anticoagulant product currently on the market. © 2014 The Society for Applied Microbiology.
Nanoparticles from renewable polymers
Wurm, Frederik R.; Weiss, Clemens K.
2014-01-01
The use of polymers from natural resources can bring many benefits for novel polymeric nanoparticle systems. Such polymers have a variety of beneficial properties such as biodegradability and biocompatibility, they are readily available on large scale and at low cost. As the amount of fossil fuels decrease, their application becomes more interesting even if characterization is in many cases more challenging due to structural complexity, either by broad distribution of their molecular weights (polysaccharides, polyesters, lignin) or by complex structure (proteins, lignin). This review summarizes different sources and methods for the preparation of biopolymer-based nanoparticle systems for various applications. PMID:25101259
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mishra, N.C.
1996-10-01
Neurospora has the capability to solubilize coal and the protein fraction accounting for this ability has been isolated. During this period the cola solubilizing activity (CSA) was fractionated and partially sequenced. The activity has been determined to be a tyrosinase and/or a phenol oxidase. The amino acid sequence of the protein was used to prepare oligonucleotides to identify the clone carrying Neurospora CSA. It is intended to clone the Neurospora gene into yeast, since yeast cannot solubilize coal, to further characterize the CSA.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhou, Qing; Shao, Mingwang, E-mail: mwshao@suda.edu.cn; Chen, Tao
Large-scale, high-purity and uniform strontium vanadate (Sr{sub 2}V{sub 2}O{sub 7}) nanoribbons were easily synthesized via a hydrothermal process without any surfactants. The as-prepared products were up to hundreds of micrometers in length, 200-600 nm in width, and 20 nm in thickness. These nanomaterials were employed to modify glassy carbon electrode, which displayed excellent electrochemical sensitivity in detecting dopamine in the presence of ascorbic acid. A linear relationship between the concentrations of dopamine and its oxidation peak currents was obtained. The modified electrode exhibited high reproducibility and stability, which might be found potential application in the biosensors.
Mapping of bird distributions from point count surveys
Sauer, J.R.; Pendleton, G.W.; Orsillo, Sandra; Ralph, C.J.; Sauer, J.R.; Droege, S.
1995-01-01
Maps generated from bird survey data are used for a variety of scientific purposes, but little is known about their bias and precision. We review methods for preparing maps from point count data and appropriate sampling methods for maps based on point counts. Maps based on point counts can be affected by bias associated with incomplete counts, primarily due to changes in proportion counted as a function of observer or habitat differences. Large-scale surveys also generally suffer from regional and temporal variation in sampling intensity. A simulated surface is used to demonstrate sampling principles for maps.
2010-02-01
APPENDIXES A. COUPON STOCK MATERIAL AND PREPARATION 141 B. CONTROL CHARTS 143 C. ANALYTICAL INSTRUMENTATION PARAMETERS 171 D. COUPON CHAIN-OF...were cut from stock material. Vitron® is a registered trademark of Vitron Manufacturing, Phoenix, AZ Kapton® is a register trademark of E.I. DuPont... Eft Wipe Wipe Ext. Eff. 15M 15M 15M 15M 0 300 600 0 4/4 5/5 5/5 4/4 3,740,999 ± 2,377,014 135876 ±51295 50896 ± 38227 120004 ±8130
Stable isotope dimethyl labelling for quantitative proteomics and beyond
Hsu, Jue-Liang; Chen, Shu-Hui
2016-01-01
Stable-isotope reductive dimethylation, a cost-effective, simple, robust, reliable and easy-to- multiplex labelling method, is widely applied to quantitative proteomics using liquid chromatography-mass spectrometry. This review focuses on biological applications of stable-isotope dimethyl labelling for a large-scale comparative analysis of protein expression and post-translational modifications based on its unique properties of the labelling chemistry. Some other applications of the labelling method for sample preparation and mass spectrometry-based protein identification and characterization are also summarized. This article is part of the themed issue ‘Quantitative mass spectrometry’. PMID:27644970
Rapid step-gradient purification of mitochondrial DNA.
Welter, C; Meese, E; Blin, N
1988-01-01
A convenient modification of the step gradient (CsCl/ethidium bomide) procedure is described. This rapid method allows isolation of covalently closed circular DNA separated from contaminating proteins, RNA and chromosomal DNA in ca. 5 h. Large scale preparations can be performed for circular DNA from eukaryotic organelles (mitochondria). The protocol uses organelle pelleting/NaCl-sarcosyl incubation steps for mitochondria followed by a CsCl step gradient and exhibits yields equal to the conventional procedures. It results in DNA sufficiently pure to be used for restriction endonuclease analysis, subcloning, 5'-end labeling, gel retention assays, and various types of hybridization.
[Sanitary and chemical protection during the Great Patriotic War].
Imangulov, R G; Grebeniuk, A N; Rybalko, V M; Nosov, A V
2011-05-01
During the Great Patriotic War (1941-1945) there was a real danger of use by German armies of the chemical weapon against staff of Red Army. However German command didn't risked to go on conducting large-scale chemical war against the USSR that rescued from painful death millions person. A principal cause of this decision was well organized and technically provided system of antigas protection in Red Army, including precisely organized actions of sanitary-chemical protection, qualitative preparation of military doctors on these questions and presence at them effective antidotes and other means of treatment of injuries by fighting poison gases.
Simple room-temperature preparation of high-yield large-area graphene oxide
Huang, NM; Lim, HN; Chia, CH; Yarmo, MA; Muhamad, MR
2011-01-01
Graphene has attracted much attention from researchers due to its interesting mechanical, electrochemical, and electronic properties. It has many potential applications such as polymer filler, sensor, energy conversion, and energy storage devices. Graphene-based nanocomposites are under an intense spotlight amongst researchers. A large amount of graphene is required for preparation of such samples. Lately, graphene-based materials have been the target for fundamental life science investigations. Despite graphene being a much sought-after raw material, the drawbacks in the preparation of graphene are that it is a challenge amongst researchers to produce this material in a scalable quantity and that there is a concern about its safety. Thus, a simple and efficient method for the preparation of graphene oxide (GO) is greatly desired to address these problems. In this work, one-pot chemical oxidation of graphite was carried out at room temperature for the preparation of large-area GO with ~100% conversion. This high-conversion preparation of large-area GO was achieved using a simplified Hummer’s method from large graphite flakes (an average flake size of 500 μm). It was found that a high degree of oxidation of graphite could be realized by stirring graphite in a mixture of acids and potassium permanganate, resulting in GO with large lateral dimension and area, which could reach up to 120 μm and ~8000 μm2, respectively. The simplified Hummer’s method provides a facile approach for the preparation of large-area GO. PMID:22267928
NASA Astrophysics Data System (ADS)
Li, Shi-Kuo; Yan, You-Xian; Wang, Jin-Long; Yu, Shu-Hong
2013-11-01
In this study, we report a facile bio-inspired method for large-scale preparation of highly dispersed Ag nanoparticles (NPs) on the surface of flexible reduced graphene oxide (rGO) paper with using dopamine (DA) both as a reductant and a surface modifier. Through the self-polymerization of dopamine, free-standing GO paper can be simultaneously reduced and modified with following in situ growth of monolayer Ag NPs on such a substrate. The spherical Ag NPs with an average diameter of 80 nm have a narrow size distribution and tunable cover density. Such a flexible rGO/Ag hybrid paper presents enhanced antibacterial activity against E. coli and a high active and sensitive SERS response toward Rhodamine 6G (R6G) molecules. The detection signals can be obtained while the R6G concentration is as low as to 10-8 M. This work provides a simple strategy for large-scale fabrication of monolayer Ag NPs on flexible rGO paper as a portable antibacterial substrate and a potential SERS substrate for molecular detection applications.In this study, we report a facile bio-inspired method for large-scale preparation of highly dispersed Ag nanoparticles (NPs) on the surface of flexible reduced graphene oxide (rGO) paper with using dopamine (DA) both as a reductant and a surface modifier. Through the self-polymerization of dopamine, free-standing GO paper can be simultaneously reduced and modified with following in situ growth of monolayer Ag NPs on such a substrate. The spherical Ag NPs with an average diameter of 80 nm have a narrow size distribution and tunable cover density. Such a flexible rGO/Ag hybrid paper presents enhanced antibacterial activity against E. coli and a high active and sensitive SERS response toward Rhodamine 6G (R6G) molecules. The detection signals can be obtained while the R6G concentration is as low as to 10-8 M. This work provides a simple strategy for large-scale fabrication of monolayer Ag NPs on flexible rGO paper as a portable antibacterial substrate and a potential SERS substrate for molecular detection applications. Electronic supplementary information (ESI) available: Preparation of GO aqueous colloid solution; XPS spectra of GO paper and PDA modified rGO paper; SEM images of rGO/Ag hybrid paper after immersed in mercaptoethanol solution or in high alkaline solution; photograph and SEM image of pure rGO paper after reaction with AgNO3 solution. SEM image and TEM graph of the pre-synthesized Ag NPs and their SEM images incubated with PDA modified rGO paper; SERS spectra of R6G (1.0 × 10-4 M) molecules before and after cleaning with concentrated hydrochloric acid liquid taken on rGO/Ag hybrid paper obtained by a reaction with 1.0 M AgNO3 solution; SERS spectra of R6G (1.0 × 10-4 M) molecules with different reusable cycles taken on rGO/Ag hybrid paper obtained by a reaction with 1.0 M AgNO3 solution; comparison between different kinds of substrates with the detection limit toward R6G. See DOI: 10.1039/c3nr03857b
NASA Astrophysics Data System (ADS)
Gao, Jiefeng; Song, Xin; Huang, Xuewu; Wang, Ling; Li, Bei; Xue, Huaiguo
2018-05-01
Non-solvent assisted electrospinning was proposed for fabricating Polymethylmethacrylate (PMMA) microspheres and fibers with a hollow core and porous shell, which could be used for oil adsorption and oil/water separation. Propanediol was chosen as the non-solvent because of its high surface tension and viscosity as well as large phase separation tendency with polymer, which was beneficial to the formation of both the hollow core and porous shell during the electrospinning. With the increase of the polymer solution concentration, the microsphere gradually evolved to the bead-on-string geometry and finally to a continuous fiber form, indicating the transition from electro-spraying to electrospinning. The hollow core and dense surface pores enhanced the hydrophobicity, oleophilicity, permeability, and specific surface area of the fibers, and hence imparted the fibrous mat a high oil adsorption capacity. When the porous hollow microspheres were electro-sprayed onto the stainless steel mesh followed by the PDMS modification, the modified mesh became super-hydrophobic and super-oleophilic with the contact angle of 153° and sliding angle of 4°. The as-prepared mesh showed rapid oil/water separation with high efficiency and excellent recycling performance. The flux for separation of oil/water mixture could reach as high as 11,000 L m-2 h-1. This facile non-solvent assisted electrospinning method provides a new avenue for preparation of multifunctional porous materials which possess potential applications in large-scale oil/water separation.
NASA Astrophysics Data System (ADS)
Wang, Ming-Shan; Lei, Ming; Wang, Zhi-Qiang; Zhao, Xing; Xu, Jun; Yang, Wei; Huang, Yun; Li, Xing
2016-03-01
Nano tin dioxide-carbon (SnO2/C) composites prepared by various carbon materials, such as carbon nanotubes, porous carbon, and graphene, have attracted extensive attention in wide fields. However, undesirable concerns of nanoparticles, including in higher surface area, low tap density, and self-agglomeration, greatly restricted their large-scale practical applications. In this study, novel porous micron-SnO2/C (p-SnO2/C) composites are scalable prepared by a simple hydrothermal approach using glucose as a carbon source and Pluronic F127 as a pore forming agent/soft template. The SnO2 nanoparticles were homogeneously dispersed in micron carbon spheres by assembly with F127/glucose. The continuous three-dimensional porous carbon networks have effectively provided strain relaxation for SnO2 volume expansion/shrinkage during lithium insertion/extraction. In addition, the carbon matrix could largely minimize the direct exposure of SnO2 to the electrolyte, thus ensure formation of stable solid electrolyte interface films. Moreover, the porous structure could also create efficient channels for the fast transport of lithium ions. As a consequence, the p-SnO2/C composites exhibit stable cycle performance, such as a high capacity retention of over 96% for 100 cycles at a current density of 200 mA g-1 and a long cycle life up to 800 times at a higher current density of 1000 mA g-1.
Ground-water flow in low permeability environments
Neuzil, Christopher E.
1986-01-01
Certain geologic media are known to have small permeability; subsurface environments composed of these media and lacking well developed secondary permeability have groundwater flow sytems with many distinctive characteristics. Moreover, groundwater flow in these environments appears to influence the evolution of certain hydrologic, geologic, and geochemical systems, may affect the accumulation of pertroleum and ores, and probably has a role in the structural evolution of parts of the crust. Such environments are also important in the context of waste disposal. This review attempts to synthesize the diverse contributions of various disciplines to the problem of flow in low-permeability environments. Problems hindering analysis are enumerated together with suggested approaches to overcoming them. A common thread running through the discussion is the significance of size- and time-scale limitations of the ability to directly observe flow behavior and make measurements of parameters. These limitations have resulted in rather distinct small- and large-scale approaches to the problem. The first part of the review considers experimental investigations of low-permeability flow, including in situ testing; these are generally conducted on temporal and spatial scales which are relatively small compared with those of interest. Results from this work have provided increasingly detailed information about many aspects of the flow but leave certain questions unanswered. Recent advances in laboratory and in situ testing techniques have permitted measurements of permeability and storage properties in progressively “tighter” media and investigation of transient flow under these conditions. However, very large hydraulic gradients are still required for the tests; an observational gap exists for typical in situ gradients. The applicability of Darcy's law in this range is therefore untested, although claims of observed non-Darcian behavior appear flawed. Two important nonhydraulic flow phenomena, osmosis and ultrafiltration, are experimentally well established in prepared clays but have been incompletely investigated, particularly in undisturbed geologic media. Small-scale experimental results form much of the basis for analyses of flow in low-permeability environments which occurs on scales of time and size too large to permit direct observation. Such large-scale flow behavior is the focus of the second part of the review. Extrapolation of small-scale experimental experience becomes an important and sometimes controversial problem in this context. In large flow systems under steady state conditions the regional permeability can sometimes be determined, but systems with transient flow are more difficult to analyze. The complexity of the problem is enhanced by the sensitivity of large-scale flow to the effects of slow geologic processes. One-dimensional studies have begun to elucidate how simple burial or exhumation can generate transient flow conditions by changing the state of stress and temperature and by burial metamorphism. Investigation of the more complex problem of the interaction of geologic processes and flow in two and three dimensions is just beginning. Because these transient flow analyses have largely been based on flow in experimental scale systems or in relatively permeable systems, deformation in response to effective stress changes is generally treated as linearly elastic; however, this treatment creates difficulties for the long periods of interest because viscoelastic deformation is probably significant. Also, large-scale flow simulations in argillaceous environments generally have neglected osmosis and ultrafiltration, in part because extrapolation of laboratory experience with coupled flow to large scales under in situ conditions is controversial. Nevertheless, the effects are potentially quite important because the coupled flow might cause ultra long lived transient conditions. The difficulties associated with analysis are matched by those of characterizing hydrologic conditions in tight environments; measurements of hydraulic head and sampling of pore fluids have been done only rarely because of the practical difficulties involved. These problems are also discussed in the second part of this paper.
Major Incident Hospital: Development of a Permanent Facility for Management of Incident Casualties.
Marres, Geertruid; Bemelman, Michael; van der Eijk, John; Leenen, Luke
2009-06-01
Preparation is essential to cope with the challenge of providing optimal care when there is a sudden, unexpected surge of casualties due to a disaster or major incident. By definition, the requirements of such cases exceed the standard care facilities of hospitals in qualitative or quantitative respects and interfere with the care of regular patients. To meet the growing demands to be prepared for disasters, a permanent facility to provide structured, prepared relief in such situations was developed. A permanent but reserved Major Incident Hospital (MIH) has been developed through cooperation between a large academic medical institution, a trauma center, a military hospital, and the National Poison Information Centre (NVIC). The infrastructure, organization, support systems, training and systematic working methods of the MIH are designed to create order in a chaotic, unexpected situation and to optimize care and logistics in any possible scenario. Focus points are: patient flow and triage, registration, communication, evaluation and training. Research and the literature are used to identify characteristic pitfalls due to the chaos associated with and the unexpected nature of disasters, and to adapt our organization. At the MIH, the exceptional has become the core business, and preparation for disaster and large-scale emergency care is a daily occupation. An Emergency Response Protocol enables admittance to the normally dormant hospital of up to 100 (in exceptional cases even 300) patients after a start-up time of only 15 min. The Patient Barcode Registration System (PBR) with EAN codes guarantees quick and adequate registration of patient data in order to facilitate good medical coordination and follow-up during a major incident. The fact that the hospital is strictly reserved for this type of care guarantees availability and minimizes impact on normal care. When it is not being used during a major incident, there is time to address training and research. Collaboration with the NVIC and infrastructural adjustments enable us to not only care for patients with physical trauma, but also to provide centralized care of patients under quarantine conditions for, say, MRSA, SARS, smallpox, chemical or biological hazards. Triage plays an important role in medical disaster management and is therefore key to organization and infrastructure. Caps facilitate role distribution and recognizibility. The PBR resulted in more accurate registration and real-time availability of patient and group information. Infrastructure and a plan is not enough; training, research and evaluation are necessary to continuously work on disaster preparedness. The MIH in Utrecht (Netherlands) is a globally unique facility that can provide immediate emergency care for multiple casualties under exceptional circumstances. Resulting from the cooperation between a large academic medical institution, a trauma center, a military hospital and the NVIC, the MIH offers not only a good and complete infrastructure but also the expertise required to provide large-scale emergency care during disasters and major incidents.
Magnetic storm generation by large-scale complex structure Sheath/ICME
NASA Astrophysics Data System (ADS)
Grigorenko, E. E.; Yermolaev, Y. I.; Lodkina, I. G.; Yermolaev, M. Y.; Riazantseva, M.; Borodkova, N. L.
2017-12-01
We study temporal profiles of interplanetary plasma and magnetic field parameters as well as magnetospheric indices. We use our catalog of large-scale solar wind phenomena for 1976-2000 interval (see the catalog for 1976-2016 in web-side ftp://ftp.iki.rssi.ru/pub/omni/ prepared on basis of OMNI database (Yermolaev et al., 2009)) and the double superposed epoch analysis method (Yermolaev et al., 2010). Our analysis showed (Yermolaev et al., 2015) that average profiles of Dst and Dst* indices decrease in Sheath interval (magnetic storm activity increases) and increase in ICME interval. This profile coincides with inverted distribution of storm numbers in both intervals (Yermolaev et al., 2017). This behavior is explained by following reasons. (1) IMF magnitude in Sheath is higher than in Ejecta and closed to value in MC. (2) Sheath has 1.5 higher efficiency of storm generation than ICME (Nikolaeva et al., 2015). The most part of so-called CME-induced storms are really Sheath-induced storms and this fact should be taken into account during Space Weather prediction. The work was in part supported by the Russian Science Foundation, grant 16-12-10062. References. 1. Nikolaeva N.S., Y. I. Yermolaev and I. G. Lodkina (2015), Modeling of the corrected Dst* index temporal profile on the main phase of the magnetic storms generated by different types of solar wind, Cosmic Res., 53(2), 119-127 2. Yermolaev Yu. I., N. S. Nikolaeva, I. G. Lodkina and M. Yu. Yermolaev (2009), Catalog of Large-Scale Solar Wind Phenomena during 1976-2000, Cosmic Res., , 47(2), 81-94 3. Yermolaev, Y. I., N. S. Nikolaeva, I. G. Lodkina, and M. Y. Yermolaev (2010), Specific interplanetary conditions for CIR-induced, Sheath-induced, and ICME-induced geomagnetic storms obtained by double superposed epoch analysis, Ann. Geophys., 28, 2177-2186 4. Yermolaev Yu. I., I. G. Lodkina, N. S. Nikolaeva and M. Yu. Yermolaev (2015), Dynamics of large-scale solar wind streams obtained by the double superposed epoch analysis, J. Geophys. Res. Space Physics, 120, doi:10.1002/2015JA021274 5. Yermolaev Y. I., I. G. Lodkina, N. S. Nikolaeva, M. Y. Yermolaev, M. O. Riazantseva (2017), Some Problems of Identification of Large-Scale Solar Wind types and Their Role in the Physics of the Magnetosphere, Cosmic Res., 55(3), pp. 178-189. DOI: 10.1134/S0010952517030029
NASA Astrophysics Data System (ADS)
Musalek, Radek; Medricky, Jan; Tesar, Tomas; Kotlan, Jiri; Pala, Zdenek; Lukac, Frantisek; Illkova, Ksenia; Hlina, Michal; Chraska, Tomas; Sokolowski, Pawel; Curry, Nicholas
2017-12-01
Introduction of suspension and solution plasma spraying led to a breakthrough in the deposition of yttria-stabilized zirconia (YSZ) coatings and enabled preparation of new types of layers. However, their deposition with high feed rates needed, for example, for the deposition of thermal barrier coatings (TBCs) on large-scale components, is still challenging. In this study, possibility of high-throughput plasma spraying of YSZ coatings is demonstrated for the latest generation of high-enthalpy hybrid water-stabilized plasma (WSP-H) torch technology. The results show that microstructure of the coatings prepared by WSP-H may be tailored for specific applications by the choice of deposition conditions, in particular formulation of the liquid feedstock. Porous and columnar coatings with low thermal conductivity (0.5-0.6 W/mK) were prepared from commercial ethanol-based suspension. Dense vertically cracked coatings with higher thermal conductivity but also higher internal cohesion were deposited from suspension containing ethanol/water mixture and coarser YSZ particles. Spraying of solution formulated from diluted zirconium acetate and yttrium nitrate hexahydrate led also to the successful deposition of YSZ coating combining regions of porous and denser microstructure and providing both low thermal conductivity and improved cohesion of the coating. Enthalpy content, liquid-plasma interaction and coating buildup mechanisms are also discussed.
NASA Astrophysics Data System (ADS)
Feng, Guang; Wu, Botao; Qayyum Khan, Abdul; Zeng, Heping
2018-05-01
Reduced titanium dioxide (TiO2‑x) due to its extraordinary visible light absorption has been widely investigated in photodegradation and water splitting nowadays. However, conventional routes to synthesize reduced TiO2 usually demand multiple preparation steps, harsh controlled conditions or expensive facilities. Here we developed a single-step in situ approach to prepare the gray TiO2‑x nanoparticles (sub-10 nm) effectively by the glow discharge plasma electrolysis (GDPE) under atmospheric pressure. The co-existence of self-doped oxygen vacancies and Ti3+ in the generated TiO2‑x nanoparticles is demonstrated by electron paramagnetic resonance (EPR). The tunable ratio of bulk/surface defect can be realized by controlling the glow discharge power directly. It should be noticed that Ti3+ in the synthesized TiO2‑x are quite stable in ambient air. The UV–vis spectra of gray TiO2‑x show an enhanced visible light absorption, which leads to high visible-light photocatalytic activity. Moreover, the as-prepared TiO2‑x after 6 months storage still shows excellent stability during photocatalytic reactions. Owing to its simplicity and effectivity, this preparation method with GDPE should provide a large-scale production for TiO2‑x with high photoactivity.
Specimen preparation, imaging, and analysis protocols for knife-edge scanning microscopy.
Choe, Yoonsuck; Mayerich, David; Kwon, Jaerock; Miller, Daniel E; Sung, Chul; Chung, Ji Ryang; Huffman, Todd; Keyser, John; Abbott, Louise C
2011-12-09
Major advances in high-throughput, high-resolution, 3D microscopy techniques have enabled the acquisition of large volumes of neuroanatomical data at submicrometer resolution. One of the first such instruments producing whole-brain-scale data is the Knife-Edge Scanning Microscope (KESM), developed and hosted in the authors' lab. KESM has been used to section and image whole mouse brains at submicrometer resolution, revealing the intricate details of the neuronal networks (Golgi), vascular networks (India ink), and cell body distribution (Nissl). The use of KESM is not restricted to the mouse nor the brain. We have successfully imaged the octopus brain, mouse lung, and rat brain. We are currently working on whole zebra fish embryos. Data like these can greatly contribute to connectomics research; to microcirculation and hemodynamic research; and to stereology research by providing an exact ground-truth. In this article, we will describe the pipeline, including specimen preparation (fixing, staining, and embedding), KESM configuration and setup, sectioning and imaging with the KESM, image processing, data preparation, and data visualization and analysis. The emphasis will be on specimen preparation and visualization/analysis of obtained KESM data. We expect the detailed protocol presented in this article to help broaden the access to KESM and increase its utilization.
Comparative analyses of industrial-scale human platelet lysate preparations.
Pierce, Jan; Benedetti, Eric; Preslar, Amber; Jacobson, Pam; Jin, Ping; Stroncek, David F; Reems, Jo-Anna
2017-12-01
Efforts are underway to eliminate fetal bovine serum from mammalian cell cultures for clinical use. An emerging, viable replacement option for fetal bovine serum is human platelet lysate (PL) as either a plasma-based or serum-based product. Nine industrial-scale, serum-based PL manufacturing runs (i.e., lots) were performed, consisting of an average ± standard deviation volume of 24.6 ± 2.2 liters of pooled, platelet-rich plasma units that were obtained from apheresis donors. Manufactured lots were compared by evaluating various biochemical and functional test results. Comprehensive cytokine profiles of PL lots and product stability tests were performed. Global gene expression profiles of mesenchymal stromal cells (MSCs) cultured with plasma-based or serum-based PL were compared to MSCs cultured with fetal bovine serum. Electrolyte and protein levels were relatively consistent among all serum-based PL lots, with only slight variations in glucose and calcium levels. All nine lots were as good as or better than fetal bovine serum in expanding MSCs. Serum-based PL stored at -80°C remained stable over 2 years. Quantitative cytokine arrays showed similarities as well as dissimilarities in the proteins present in serum-based PL. Greater differences in MSC gene expression profiles were attributable to the starting cell source rather than with the use of either PL or fetal bovine serum as a culture supplement. Using a large-scale, standardized method, lot-to-lot variations were noted for industrial-scale preparations of serum-based PL products. However, all lots performed as well as or better than fetal bovine serum in supporting MSC growth. Together, these data indicate that off-the-shelf PL is a feasible substitute for fetal bovine serum in MSC cultures. © 2017 AABB.
Sun, Guodong; Zhou, Zihong; Luo, Zhonghua; Wang, Hailong; Chen, Lei; Xu, Yongbo; Li, Shun; Jian, Weilin; Zeng, Jiebin; Hu, Benquan; Han, Xiaodong; Lin, Yicao; Wang, Zhongqing
2017-08-18
A highly efficient preparation of enantiomerically pure syn aryl β-hydroxy α-dibenzylamino esters is reported. The outcome was achieved via dynamic kinetic resolution and asymmetric transfer hydrogenation of aryl α-dibenzylamino β-keto esters. The desired products were obtained in high yields (up to 98%) with excellent diastereoselectivity (>20:1 dr) and enantioselectivity (up to >99% ee). Furthermore, this method was applied for the gram-scale preparation of droxidopa.
2008-05-20
Surrounded by work platforms, NASA's first full-scale Orion abort flight test (AFT) crew module (center) is undergoing preparations at the NASA Dryden Flight Research Center in California for the first flight test of Orion's launch abort system.
NASA Astrophysics Data System (ADS)
Gindt, Brandon
This dissertation outlines a novel path towards improved understanding and function of proton exchange membranes (PEMs) for redox flow batteries, a large-scale battery storage device. This research uses synthetic methods and nanotechnology through two different approaches to prepare tailored polymer membranes: 1) Ion exchange membranes with enhanced chemical structures to promote membrane morphology on the nano-scale were prepared. Specifically, functional polysulfones (PSUs) were synthesized from different pre-sulfonated monomers. These PSUs have controlled placement and content of unique sulfonic acid moieties. PEMs were fabricated and characterized. The new PEMs showed desirable physical properties and performance in a vanadium redox flow battery (VRFB) cell. 2) Nanoporous PSU membranes were fabricated via post-hydrolysis of polylactide (PLA) from PLA-PSU-PLA triblock copolymer membranes. The controlled morphology and pore size of the resulting nanoporous membranes were evaluated by different microscopy and scattering techniques to understand structure-property relationships. Further, the resulting nanopore surface was chemically modified with sulfonic acid moieties. Membranes were analyzed and evaluated as separators for a VRFB. The chemically modified nanoporous PEMs exhibited unique behavior with respect to their ion conductivity when exposed to solutions of increasing acid concentration. In addition, the hierarchical micro-nanoporous membranes developed further showed promising structure and properties.
Synthesis of inorganic fullerene-like WS2 nanoparticles and their lubricating performance
NASA Astrophysics Data System (ADS)
Yang, Haibin; Liu, Shikai; Li, Jixue; Li, Minghui; Peng, Gang; Zou, Guangtian
2006-03-01
A facile, large-scale and low-cost route was used to synthesize inorganic fullerene-like (IF) WS2 nanoparticles by the reaction of sulfur powder (S) and as-prepared WO3 nanoparticles in a hydrogen atmosphere at a heating temperature of 500-650 °C. The as-synthesized IF-WS2 nanoparticles are of a closed hollow cage structure with an average size of about 50 nm. The composition, morphology and structure of the products were characterized by XRD, TEM, FE-SEM, and HRTEM. The influences of the main reaction conditions were investigated and the possible growth mechanism are proposed. It is worth noting that through changing the amount of as-prepared composite powder (WO3 and S) and the content of hydrogen, yields of IF-WS2 in larger scales can accordingly be easily obtained, and such a synthetic route may also be used in the synthesis of other transition IF metal dichalcogenides. Furthermore, tribological experiments emphasized the important role played by these as-synthesized IF-WS2 nanoparticles in providing excellent lubricating performance, which may bring a much brighter future for their applications in the lubricating field, or even arouse great interest of both scientists and industrialists for their many other important applications.
Nonlinear optical microscopy and ultrasound imaging of human cervical structure
Reusch, Lisa M.; Feltovich, Helen; Carlson, Lindsey C.; Hall, Gunnsteinn; Campagnola, Paul J.; Eliceiri, Kevin W.
2013-01-01
Abstract. The cervix softens and shortens as its collagen microstructure rearranges in preparation for birth, but premature change may lead to premature birth. The global preterm birth rate has not decreased despite decades of research, likely because cervical microstructure is poorly understood. Our group has developed a multilevel approach to evaluating the human cervix. We are developing quantitative ultrasound (QUS) techniques for noninvasive interrogation of cervical microstructure and corroborating those results with high-resolution images of microstructure from second harmonic generation imaging (SHG) microscopy. We obtain ultrasound measurements from hysterectomy specimens, prepare the tissue for SHG, and stitch together several hundred images to create a comprehensive view of large areas of cervix. The images are analyzed for collagen orientation and alignment with curvelet transform, and registered with QUS data, facilitating multiscale analysis in which the micron-scale SHG images and millimeter-scale ultrasound data interpretation inform each other. This novel combination of modalities allows comprehensive characterization of cervical microstructure in high resolution. Through a detailed comparative study, we demonstrate that SHG imaging both corroborates the quantitative ultrasound measurements and provides further insight. Ultimately, a comprehensive understanding of specific microstructural cervical change in pregnancy should lead to novel approaches to the prevention of preterm birth. PMID:23412434
Good Manufacturing Practices production and analysis of a DNA vaccine against dental caries.
Yang, Ya-ping; Li, Yu-hong; Zhang, Ai-hua; Bi, Lan; Fan, Ming-wen
2009-11-01
To prepare a clinical-grade anti-caries DNA vaccine pGJA-P/VAX and explore its immune effect and protective efficacy against a cariogenic bacterial challenge. A large-scale industrial production process was developed under Good Manufacturing Practices (GMP) by combining and optimizing common unit operations such as alkaline lysis, precipitation, endotoxin removal and column chromatography. Quality controls of the purified bulk and final lyophilized vaccine were conducted according to authoritative guidelines. Mice and gnotobiotic rats were intranasally immunized with clinical-grade pGJA-P/VAX with chitosan. Antibody levels of serum IgG and salivary SIgA were assessed by an enzyme-linked immunosorbent assay (ELISA), and caries activity was evaluated by the Keyes method. pGJA-P/VAX and pVAX1 prepared by a laboratory-scale commercial kit were used as controls. The production process proved to be scalable and reproducible. Impurities including host protein, residual RNA, genomic DNA and endotoxin in the purified plasmid were all under the limits of set specifications. Intranasal vaccination with clinical-grade pGJA-P/VAX induced higher serum IgG and salivary SIgA in both mice and gnotobiotic rats. While in the experimental caries model, the enamel (E), dentinal slight (Ds), and dentinal moderate (Dm) caries lesions were reduced by 21.1%, 33.0%, and 40.9%, respectively. The production process under GMP was efficient in preparing clinical-grade pGJA-P/VAX with high purity and intended effectiveness, thus facilitating future clinical trials for the anti-caries DNA vaccine.
Cost estimate for a proposed GDF Suez LNG testing program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Blanchat, Thomas K.; Brady, Patrick Dennis; Jernigan, Dann A.
2014-02-01
At the request of GDF Suez, a Rough Order of Magnitude (ROM) cost estimate was prepared for the design, construction, testing, and data analysis for an experimental series of large-scale (Liquefied Natural Gas) LNG spills on land and water that would result in the largest pool fires and vapor dispersion events ever conducted. Due to the expected cost of this large, multi-year program, the authors utilized Sandia's structured cost estimating methodology. This methodology insures that the efforts identified can be performed for the cost proposed at a plus or minus 30 percent confidence. The scale of the LNG spill, fire,more » and vapor dispersion tests proposed by GDF could produce hazard distances and testing safety issues that need to be fully explored. Based on our evaluations, Sandia can utilize much of our existing fire testing infrastructure for the large fire tests and some small dispersion tests (with some modifications) in Albuquerque, but we propose to develop a new dispersion testing site at our remote test area in Nevada because of the large hazard distances. While this might impact some testing logistics, the safety aspects warrant this approach. In addition, we have included a proposal to study cryogenic liquid spills on water and subsequent vaporization in the presence of waves. Sandia is working with DOE on applications that provide infrastructure pertinent to wave production. We present an approach to conduct repeatable wave/spill interaction testing that could utilize such infrastructure.« less
Scaleable catalytic asymmetric Strecker syntheses of unnatural α-amino acids
Zuend, Stephan J.; Coughlin, Matthew P.; Lalonde, Mathieu P.; Jacobsen, Eric N.
2009-01-01
α-Amino acids are essential building blocks for protein synthesis, and are also widely useful as components of medicinally active molecules and chiral catalysts.1,2,3,4,5 Efficient chemo-enzymatic methods for the synthesis of enantioenriched α-amino acids have been devised, but the scope of these methods for the synthesis of unnatural amino acids is limited.6,7 Alkene hydrogenation is broadly useful for enantioselective catalytic synthesis of many classes of amino acids,8,9 but this approach is not applicable to the synthesis of α-amino acids bearing aryl or quaternary alkyl α-substituents. The Strecker synthesis—the reaction of an imine or imine equivalent with hydrogen cyanide, followed by nitrile hydrolysis—is an especially versatile chemical method for the synthesis of racemic α-amino acids (Fig. 1).10,11 Asymmetric Strecker syntheses using stoichiometric chiral reagents have been applied successfully on gram-to-multi-kilogram scales to the preparation of enantiomerically enriched α-amino acids.12,13,14 In principle, Strecker syntheses employing sub-stoichiometric quantities of a chiral reagent provide a practical alternative to these approaches, but the reported catalytic asymmetric methods have seen only limited use on preparative scales (e.g., > 1 gram).15,16 The limited use of existing catalytic methodologies may be ascribed to several important practical drawbacks, including the relatively complex and precious nature of the catalysts, and the requisite use of hazardous cyanide sources. Herein we report a new catalytic asymmetric method for the syntheses of highly enantiomerically enriched non-proteinogenic amino acids using a simple chiral amido-thiourea catalyst to control the key hydrocyanation step. Because this catalyst is robust and lacks sensitive functional groups, it is compatible with safely handled aqueous cyanide salts, and is thus adaptable to large-scale synthesis. This new methodology can be applied to the efficient syntheses of amino acids that are not readily prepared by enzymatic methods or by chemical hydrogenation. PMID:19829379
Rokach, Ariel; Pinkert, Moshe; Nemet, Dani; Goldberg, Avishay; Bar-Dayan, Yaron
2008-01-01
During the last few decades, various global disasters have rendered nations helpless (such as Thailand's tsunami and earthquakes in Turkey, Pakistan, Iran, and India). A lack of knowledge and resources make it difficult to address such disasters. Preparedness for a national disaster is expensive, and in most cases, unachievable even for modern countries. International collaboration might be useful for coping with large-scale disasters. Preparedness for international collaboration includes drills. Two such drills held by the Israeli Home Front Command and other military and civilian bodies with the nations of Greece and Turkey are described in this article. The data were gathered from formal debriefings of the Israeli teams collaborating in two separate drills with Greek and Turkish teams. Preparations began four months before the drills were conducted and included three meetings between Israeli and foreign officials. The Israeli and foreign officials agreed upon the drill layout, logistics, communications, residence, real-time medicine, hardware, and equipment. The drills took place in Greece and Turkey and lasted four days. The first day included meetings between the teams and logistics preparations. The second and third days were devoted to exercises. The drills included evacuating casualties from a demolition zone and treating typical injuries such as crush syndrome. Every day ended with a formal debriefing by the teams' commanders. The fourth day included a ceremony and transportation back home. Members in both teams felt the drills improved their skills and had an important impact on creating common language that would enhance cooperation during a real disaster. A key factor in the management of large-scale disasters is coordination between countries. International drills are important to create common language within similar regulations.
Chang, Hye-Sook; Mizukami, Keijiro; Yabuki, Akira; Hossain, Mohammad A; Rahman, Mohammad M; Uddin, Mohammad M; Arai, Toshiro; Yamato, Osamu
2010-09-01
Collie eye anomaly (CEA) is a canine inherited ocular disease that shows a wide variety of manifestations and severity of clinical lesions. Recently, a CEA-associated mutation was reported, and a DNA test that uses conventional polymerase chain reaction (PCR) has now become available. The objective of the current study was to develop a novel rapid genotyping technique by using SYBR Green-based real-time PCR for future large-scale surveys as a key part in the strategy to eradicate CEA by selective breeding. First, a SYBR Green-based real-time PCR assay for genotyping of CEA was developed and evaluated by using purified DNA samples from normal, carrier, and affected Border Collies in which genotypes had previously been determined by conventional PCR. This real-time PCR assay demonstrated appropriate amplifications in all genotypes, and the results were consistent with those of conventional PCR. Second, the availability of Flinders Technology Associates filter paper (FTA card) as DNA templates for the real-time PCR assay was evaluated by using blood and saliva specimens to determine suitability for CEA screening. DNA-containing solution prepared from a disc of blood- or saliva-spotted FTA cards was available directly as templates for the real-time PCR assay when the volume of solution was 2.5% of the PCR mixture. In conclusion, SYBR Green-based real-time PCR combined with FTA cards is a rapid genotyping technique for CEA that can markedly shorten the overall time required for genotyping as well as simplify the sample preparation. Therefore, this newly developed technique suits large-scale screening in breeding populations of Collie-related breeds.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gillispie, Obie William; Worl, Laura Ann; Veirs, Douglas Kirk
A mixture of chlorine-containing, impure plutonium oxides has been produced and has been given the name Master Blend. This large quantity of well-characterized chlorinecontaining material is available for use in the Integrated Surveillance and Monitoring Program for shelf-life experiments. It is intended to be representative of materials packaged to meet DOE-STD-3013.1 The Master Blend contains a mixture of items produced in Los Alamos National Laboratory’s (LANL) electro-refining pyrochemical process in the late 1990s. Twenty items were crushed and sieved, calcined to 800ºC for four hours, and blended multiple times. This process resulted in four batches of Master Blend. Calorimetry andmore » density data on material from the four batches indicate homogeneity.« less
NASA Technical Reports Server (NTRS)
Johnson, B.
1988-01-01
The Coastal Zone Color Scanner (CZCS) spacecraft ocean color instrument is capable of measuring and mapping global ocean surface chlorophyll concentration. It is a scanning radiometer with multiband capability. With new electronics and some mechanical, and optical re-work, it probably can be made flight worthy. Some additional components of a second flight model are also available. An engineering study and further tests are necessary to determine exactly what effort is required to properly prepare the instrument for spaceflight and the nature of interfaces to prospective spacecraft. The CZCS provides operational instrument capability for monitoring of ocean productivity and currents. It could be a simple, low cost alternative to developing new instruments for ocean color imaging. Researchers have determined that with global ocean color data they can: specify quantitatively the role of oceans in the global carbon cycle and other major biogeochemical cycles; determine the magnitude and variability of annual primary production by marine phytoplankton on a global scale; understand the fate of fluvial nutrients and their possible affect on carbon budgets; elucidate the coupling mechanism between upwelling and large scale patterns in ocean basins; answer questions concerning the large scale distribution and timing of spring blooms in the global ocean; acquire a better understanding of the processes associated with mixing along the edge of eddies, coastal currents, western boundary currents, etc., and acquire global data on marine optical properties.
WeaVR: a self-contained and wearable immersive virtual environment simulation system.
Hodgson, Eric; Bachmann, Eric R; Vincent, David; Zmuda, Michael; Waller, David; Calusdian, James
2015-03-01
We describe WeaVR, a computer simulation system that takes virtual reality technology beyond specialized laboratories and research sites and makes it available in any open space, such as a gymnasium or a public park. Novel hardware and software systems enable HMD-based immersive virtual reality simulations to be conducted in any arbitrary location, with no external infrastructure and little-to-no setup or site preparation. The ability of the WeaVR system to provide realistic motion-tracked navigation for users, to improve the study of large-scale navigation, and to generate usable behavioral data is shown in three demonstrations. First, participants navigated through a full-scale virtual grocery store while physically situated in an open grass field. Trajectory data are presented for both normal tracking and for tracking during the use of redirected walking that constrained users to a predefined area. Second, users followed a straight path within a virtual world for distances of up to 2 km while walking naturally and being redirected to stay within the field, demonstrating the ability of the system to study large-scale navigation by simulating virtual worlds that are potentially unlimited in extent. Finally, the portability and pedagogical implications of this system were demonstrated by taking it to a regional high school for live use by a computer science class on their own school campus.
Pang, Xuming; Wei, Qian; Zhou, Jianxin; Ma, Huiyang
2018-06-19
In order to achieve cermet-based solar absorber coatings with long-term thermal stability at high temperatures, a novel single-layer, multi-scale TiC-Ni/Mo cermet coating was first prepared using laser cladding technology in atmosphere. The results show that the optical properties of the cermet coatings using laser cladding were much better than the preplaced coating. In addition, the thermal stability of the optical properties for the laser cladding coating were excellent after annealing at 650 °C for 200 h. The solar absorptance and thermal emittance of multi-scale cermet coating were 85% and 4.7% at 650 °C. The results show that multi-scale cermet materials are more suitable for solar-selective absorbing coating. In addition, laser cladding is a new technology that can be used for the preparation of spectrally-selective coatings.
NASA Astrophysics Data System (ADS)
Amiri, Ahmad; Ahmadi, Goodarz; Shanbedi, Mehdi; Savari, Maryam; Kazi, S. N.; Chew, B. T.
2015-12-01
Capacitive deionization (CDI) is a promising procedure for removing various charged ionic species from brackish water. The performance of graphene-based material in capacitive deionization is lower than the expectation of the industry, so highly-crumpled, few-layered graphene (HCG) and highly-crumpled nitrogen-doped graphene (HCNDG) with high surface area have been introduced as promising candidates for CDI electrodes. Thus, HCG and HCNDG were prepared by exfoliation of graphite in the presence of liquid-phase, microwave-assisted methods. An industrially-scalable, cost-effective, and simple approach was employed to synthesize HCG and HCNDG, resulting in few-layered graphene and nitrogen-doped graphene with large specific surface area. Then, HCG and HCNDG were utilized for manufacturing a new class of carbon nanostructure-based electrodes for use in large-scale CDI equipment. The electrosorption results indicated that both the HCG and HCNDG have fairly large specific surface areas, indicating their huge potential for capacitive deionization applications.
The Role of APEX as a Pathfinder for AtLAST
NASA Astrophysics Data System (ADS)
Wyrowski, Friedrich
2018-01-01
Now more than 12 years in operation, the Atacama Pathfinder Experiment (APEX) 12 m submillimeter telescope has significantly contributed to a wide variety of submillimeter astronomy science areas, ranging from the discoveries of new molecules to large and deep imaging of the submillimeter sky. While ALMA operation is in full swing, APEX is strengthening its role not only as pathfinder for studying large source samples and spatial scales to prepare detailed high angular resolution ALMA follow ups, but also as fast response instruments to complement new results from ALMA. Furthermore, APEX ensures southern hemisphere access for submillimeter projects complementing archival Herschel research as well as new SOFIA science. With new broadband and multipixel receivers as well as large cameras for wide-field continuum imaging, APEX will pave the way towards the science envisioned with ATLAST. In this contribution, the current status and ongoing upgrades of APEX will be discussed, with an emphasis on the importance of continuous cutting edge science and state-of-the-art instrumentation that will bridge the gap towards ATLAST.
Hanlon, Steven P; Camattari, Andrea; Abad, Sandra; Glieder, Anton; Kittelmann, Matthias; Lütz, Stephan; Wirz, Beat; Winkler, Margit
2012-06-18
A panel of human flavin monooxygenases were heterologously expressed in E. coli to obtain ready-to-use biocatalysts for the in vitro preparation of human drug metabolites. Moclobemide-N-oxide (65 mg) was the first high-priced metabolite prepared with recombinant hFMO3 on the multi-milligram scale.
Sinuous Flow in Cutting of Metals
NASA Astrophysics Data System (ADS)
Yeung, Ho; Viswanathan, Koushik; Udupa, Anirudh; Mahato, Anirban; Chandrasekar, Srinivasan
2017-11-01
Using in situ high-speed imaging, we unveil details of a highly unsteady plastic flow mode in the cutting of annealed and highly strain-hardening metals. This mesoscopic flow mode, termed sinuous flow, is characterized by repeated material folding, large rotation, and energy dissipation. Sinuous flow effects a very large shape transformation, with local strains of ten or more, and results in a characteristic mushroomlike surface morphology that is quite distinct from the well-known morphologies of metal-cutting chips. Importantly, the attributes of this unsteady flow are also fundamentally different from other well-established unsteady plastic flows in large-strain deformation, like adiabatic shear bands. The nucleation and development of sinuous flow, its dependence on material properties, and its manifestation across material systems are demonstrated. Plastic buckling and grain-scale heterogeneity are found to play key roles in triggering this flow at surfaces. Implications for modeling and understanding flow stability in large-strain plastic deformation, surface quality, and preparation of near-strain-free surfaces by cutting are discussed. The results point to the inadequacy of the widely used shear-zone models, even for ductile metals.
Yu, Pengzhan; Li, Xingqi; Li, Xiunan; Lu, Xiuling; Ma, Guanghui; Su, Zhiguo
2007-10-15
A clear and powerful chromatographic approach to purify polyethylene glycol derivatives at a preparative scale was reported, which was based on the polystyrene-divinylbenzene beads with ethanol/water as eluants. The validity of this method was verified with the reaction mixture of mPEG-Glu and mPEG propionaldehyde diethylacetal (ALD-PEG) as the model. The target products were one-step achieved with the purity of >99% on the polymer resins column at gram scale. The method developed was free from such disadvantages as utility of toxic solvent and narrow application scope, which was combined with conventional approaches. The method developed provided an appealing and attractive alternative methods for purification of PEG derivatives at a preparative scale.
Myers, Nicholas D; Feltz, Deborah L; Guillén, Félix; Dithurbide, Lori
2012-12-01
The purpose of this multistudy report was to develop, and then to provide initial validity evidence for measures derived from, the Referee Self-Efficacy Scale. Data were collected from referees (N = 1609) in the United States (n = 978) and Spain (n = 631). In Study 1 (n = 512), a single-group exploratory structural equation model provided evidence for four factors: game knowledge, decision making, pressure, and communication. In Study 2 (n = 1153), multiple-group confirmatory factor analytic models provided evidence for partial factorial invariance by country, level of competition, team gender, and sport refereed. In Study 3 (n = 456), potential sources of referee self-efficacy information combined to account for a moderate or large amount of variance in each dimension of referee self-efficacy with years of referee experience, highest level refereed, physical/mental preparation, and environmental comfort, each exerting at least two statistically significant direct effects.
On-chip purification via liquid immersion of arc-discharge synthesized multiwalled carbon nanotubes
NASA Astrophysics Data System (ADS)
Hokkanen, Matti J.; Lautala, Saara; Shao, Dongkai; Turpeinen, Tuomas; Koivistoinen, Juha; Ahlskog, Markus
2016-07-01
Arc-discharge synthesized multiwalled carbon nanotubes (AD-MWNT) have been proven to be of high quality, but their use is very limited due to difficulties in obtaining them in a clean and undamaged form. Here, we present a simple method that purifies raw AD-MWNT material in laboratory scale without damage, and that in principle can be scaled up. The method consists of depositing raw AD-MWNT material on a flat substrate and immersing the substrate slowly in water, whereby the surface tension force of the liquid-substrate contact line selectively sweeps away the larger amorphous carbon debris and leaves relatively clean MWNTs on the substrate. We demonstrate the utility of the method by preparing clean individual MWNTs for measurement of their Raman spectra. The spectra exhibit the characteristics of high-quality tubes free from contaminants. We also show how one concomitantly with the purification process can obtain large numbers of clean suspended MWNTs.
Large scale synthesis of nanostructured zirconia-based compounds from freeze-dried precursors
NASA Astrophysics Data System (ADS)
Gómez, A.; Villanueva, R.; Vie, D.; Murcia-Mascaros, S.; Martínez, E.; Beltrán, A.; Sapiña, F.; Vicent, M.; Sánchez, E.
2013-01-01
Nanocrystalline zirconia powders have been obtained at the multigram scale by thermal decomposition of precursors resulting from the freeze-drying of aqueous acetic solutions. This technique has equally made possible to synthesize a variety of nanostructured yttria or scandia doped zirconia compositions. SEM images, as well as the analysis of the XRD patterns, show the nanoparticulated character of those solids obtained at low temperature, with typical particle size in the 10-15 nm range when prepared at 673 K. The presence of the monoclinic, the tetragonal or both phases depends on the temperature of the thermal treatment, the doping concentration and the nature of the dopant. In addition, Rietveld refinement of the XRD profiles of selected samples allows detecting the coexistence of the tetragonal and the cubic phases for high doping concentration and high thermal treatment temperatures. Raman experiments suggest the presence of both phases also at relatively low treatment temperatures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
From November 1991 to April 1996, Kerr McGee Coal Corporation (K-M Coal) led a project to develop the Institute of Gas Technology (IGT) Mild Gasification (MILDGAS) process for near-term commercialization. The specific objectives of the program were to: design, construct, and operate a 24-tons/day adiabatic process development unit (PDU) to obtain process performance data suitable for further design scale-up; obtain large batches of coal-derived co-products for industrial evaluation; prepare a detailed design of a demonstration unit; and develop technical and economic plans for commercialization of the MILDGAS process. The project team for the PDU development program consisted of: K-M Coal,more » IGT, Bechtel Corporation, Southern Illinois University at Carbondale (SIUC), General Motors (GM), Pellet Technology Corporation (PTC), LTV Steel, Armco Steel, Reilly Industries, and Auto Research.« less
Solvent-free melting techniques for the preparation of lipid-based solid oral formulations.
Becker, Karin; Salar-Behzadi, Sharareh; Zimmer, Andreas
2015-05-01
Lipid excipients are applied for numerous purposes such as taste masking, controlled release, improvement of swallowability and moisture protection. Several melting techniques have evolved in the last decades. Common examples are melt coating, melt granulation and melt extrusion. The required equipment ranges from ordinary glass beakers for lab scale up to large machines such as fluid bed coaters, spray dryers or extruders. This allows for upscaling to pilot or production scale. Solvent free melt processing provides a cost-effective, time-saving and eco-friendly method for the food and pharmaceutical industries. This review intends to give a critical overview of the published literature on experiences, formulations and challenges and to show possibilities for future developments in this promising field. Moreover, it should serve as a guide for selecting the best excipients and manufacturing techniques for the development of a product with specific properties using solvent free melt processing.
Taming tosyl azide: the development of a scalable continuous diazo transfer process.
Deadman, Benjamin J; O'Mahony, Rosella M; Lynch, Denis; Crowley, Daniel C; Collins, Stuart G; Maguire, Anita R
2016-04-07
Heat and shock sensitive tosyl azide was generated and used on demand in a telescoped diazo transfer process. Small quantities of tosyl azide were accessed in a 'one pot' batch procedure using shelf stable, readily available reagents. For large scale diazo transfer reactions tosyl azide was generated and used in a telescoped flow process, to mitigate the risks associated with handling potentially explosive reagents on scale. The in situ formed tosyl azide was used to rapidly perform diazo transfer to a range of acceptors, including β-ketoesters, β-ketoamides, malonate esters and β-ketosulfones. An effective in-line quench of sulfonyl azides was also developed, whereby a sacrificial acceptor molecule ensured complete consumption of any residual hazardous diazo transfer reagent. The telescoped diazo transfer process with in-line quenching was used to safely prepare over 21 g of an α-diazocarbonyl in >98% purity without any column chromatography.
Season-ahead water quality forecasts for the Schuylkill River, Pennsylvania
NASA Astrophysics Data System (ADS)
Block, P. J.; Leung, K.
2013-12-01
Anticipating and preparing for elevated water quality parameter levels in critical water sources, using weather forecasts, is not uncommon. In this study, we explore the feasibility of extending this prediction scale to a season-ahead for the Schuylkill River in Philadelphia, utilizing both statistical and dynamical prediction models, to characterize the season. This advance information has relevance for recreational activities, ecosystem health, and water treatment, as the Schuylkill provides 40% of Philadelphia's water supply. The statistical model associates large-scale climate drivers with streamflow and water quality parameter levels; numerous variables from NOAA's CFSv2 model are evaluated for the dynamical approach. A multi-model combination is also assessed. Results indicate moderately skillful prediction of average summertime total coliform and wintertime turbidity, using season-ahead oceanic and atmospheric variables, predominantly from the North Atlantic Ocean. Models predicting the number of elevated turbidity events across the wintertime season are also explored.
Interactive exploration of coastal restoration modeling in virtual environments
NASA Astrophysics Data System (ADS)
Gerndt, Andreas; Miller, Robert; Su, Simon; Meselhe, Ehab; Cruz-Neira, Carolina
2009-02-01
Over the last decades, Louisiana has lost a substantial part of its coastal region to the Gulf of Mexico. The goal of the project depicted in this paper is to investigate the complex ecological and geophysical system not only to find solutions to reverse this development but also to protect the southern landscape of Louisiana for disastrous impacts of natural hazards like hurricanes. This paper sets a focus on the interactive data handling of the Chenier Plain which is only one scenario of the overall project. The challenge addressed is the interactive exploration of large-scale time-depending 2D simulation results and of terrain data with a high resolution that is available for this region. Besides data preparation, efficient visualization approaches optimized for the usage in virtual environments are presented. These are embedded in a complex framework for scientific visualization of time-dependent large-scale datasets. To provide a straightforward interface for rapid application development, a software layer called VRFlowVis has been developed. Several architectural aspects to encapsulate complex virtual reality aspects like multi-pipe vs. cluster-based rendering are discussed. Moreover, the distributed post-processing architecture is investigated to prove its efficiency for the geophysical domain. Runtime measurements conclude this paper.
The Challenges Of Investigating And Remediating Port Hope's Small-Scale Urban Properties - 13115
DOE Office of Scientific and Technical Information (OSTI.GOV)
Veen, Walter van; Case, Glenn; Benson, John
2013-07-01
An important component of the Port Hope Project, the larger of the two projects comprising the Port Hope Area Initiative (PHAI), is the investigation of all 4,800 properties in the Municipality of Port Hope for low level radioactive waste (LLRW) and the remediation of approximately 10% of these. Although the majority of the individual properties are not expected to involve technically sophisticated remediation programs, the large number of property owners and individually unique properties are expected to present significant logistic challenges that will require a high degree of planning, organization and communication. The protocol and lessons learned described will bemore » of interest to those considering similar programs. Information presented herein is part of a series of papers presented by the PHAI Management Office (PHAI MO) at WM Symposium '13 describing the history of the Port Hope Project and current project status. Other papers prepared for WM Symposium '13 address the large-scale site cleanup and the construction of the long-term waste management facility (LTWMF) where all of the LLRW will be consolidated and managed within an engineered, above-ground mound. (authors)« less
NASA Technical Reports Server (NTRS)
Howard, J. A.
1974-01-01
The United Nations initially contracted with NASA to carry out investigations in three countries; but now as the result of rapidly increasing interest, ERTS imagery has been/is being used in 7 additional projects related to agriculture, forestry, land-use, soils, landforms and hydrology. Initially the ERTS frames were simply used to provide a synoptic view of a large area of a developing country as a basis to regional surveys. From this, interest has extended to using reconstituted false color imagery and latterly, in co-operation with Purdue University, the use of computer generated false color mosaics and computer generated large scale maps. As many developing countries are inadequately mapped and frequently rely on outdated maps, the ERTS imagery is considered to provide a very wide spectrum of valuable data. Thematic maps can be readily prepared at a scale of 1:250,000 using standard NASA imagery. These provide coverage of areas not previously mapped and provide supplementary information and enable existing maps to be up-dated. There is also increasing evidence that ERTS imagery is useful for temporal studies and for providing a new dimension in integrated surveys.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Herrmann, A M; Ritz, K; Nunan, N
Soils are structurally heterogeneous across a wide range of spatio-temporal scales. Consequently, external environmental conditions do not have a uniform effect throughout the soil, resulting in a large diversity of micro-habitats. It has been suggested that soil function can be studied without explicit consideration of such fine detail, but recent research has indicated that the micro-scale distribution of organisms may be of importance for a mechanistic understanding of many soil functions. Due to a lack of techniques with adequate sensitivity for data collection at appropriate scales, the question 'How important are various soil processes acting at different scales for ecologicalmore » function?' is challenging to answer. The nano-scale secondary ion mass spectrometer (NanoSIMS) represents the latest generation of ion microprobes which link high-resolution microscopy with isotopic analysis. The main advantage of NanoSIMS over other secondary ion mass spectrometers is the ability to operate at high mass resolution, whilst maintaining both excellent signal transmission and spatial resolution ({approx}50 nm). NanoSIMS has been used previously in studies focusing on presolar materials from meteorites, in material science, biology, geology and mineralogy. Recently, the potential of NanoSIMS as a new tool in the study of biophysical interfaces in soils has been demonstrated. This paper describes the principles of NanoSIMS and discusses the potential of this tool to contribute to the field of biogeochemistry and soil ecology. Practical considerations (sample size and preparation, simultaneous collection of isotopes, mass resolution, isobaric interference and quantification of the isotopes of interest) are discussed. Adequate sample preparation avoiding biases in the interpretation of NanoSIMS data due to artifacts and identification of regions-of interest are of most concerns in using NanoSIMS as a new tool in biogeochemistry and soil ecology. Finally, we review the areas of research most likely to benefit from the high resolving power attainable with this new approach.« less
Muscle dysfunction in a zebrafish model of Duchenne muscular dystrophy.
Widrick, Jeffrey J; Alexander, Matthew S; Sanchez, Benjamin; Gibbs, Devin E; Kawahara, Genri; Beggs, Alan H; Kunkel, Louis M
2016-11-01
Sapje zebrafish lack the protein dystrophin and are the smallest vertebrate model of Duchenne muscular dystrophy (DMD). Their small size makes them ideal for large-scale drug discovery screens. However, the extent that sapje mimic the muscle dysfunction of higher vertebrate models of DMD is unclear. We used an optical birefringence assay to differentiate affected dystrophic sapje larvae from their unaffected siblings and then studied trunk muscle contractility at 4-7 days postfertilization. Preparation cross-sectional area (CSA) was similar for affected and unaffected larvae, yet tetanic forces of affected preparations were only 30-60% of normal. ANCOVA indicated that the linear relationship observed between tetanic force and CSA for unaffected preparations was absent in the affected population. Consequently, the average force/CSA of affected larvae was depressed 30-70%. Disproportionate reductions in twitch vs. tetanic force, and a slowing of twitch tension development and relaxation, indicated that the myofibrillar disorganization evident in the birefringence assay could not explain the entire force loss. Single eccentric contractions, in which activated preparations were lengthened 5-10%, resulted in tetanic force deficits in both groups of larvae. However, deficits of affected preparations were three- to fivefold greater at all strains and ages, even after accounting for any recovery. Based on these functional assessments, we conclude that the sapje mutant zebrafish is a phenotypically severe model of DMD. The severe contractile deficits of sapje larvae represent novel physiological endpoints for therapeutic drug screening. Copyright © 2016 the American Physiological Society.
NASA Astrophysics Data System (ADS)
Guo, Yonghong; Zhai, Gang; Ru, Yu; Wu, Chuyu; Jia, Xiaowei; Sun, Yaping; Yu, Jiawen; Kang, Zhizhong; Sun, Baomin
2018-03-01
The Flame pyrolysis method used to synthesize carbon nanotubes was studied in this work. In order to improve the quality of synthesized carbon nanotubes, it is important to change the corresponding natures of the catalyst. Two catalyst preparation methods, namely, the sol-gel method and the impregnation method, were compared in this experiment. The properties of the catalyst are analyzed in depth by energy dispersive spectrometer (EDS), x-ray diffraction (XRD), temperature program reduction (TPR). The generation of carbon nanotubes was systematically analysed through scanning electron microscope (SEM), molecule dynamics (MD), raman spectroscopy and transmission electron microscope (TEM). The results show that the catalysts prepared by the impregnation method are stickier, dispersed and easier to dip onto the probe or substrate, which is beneficial for the large-scale production of carbon tubes. The specific surface area of alumina is larger and the iron and molybdenum oxide are more evenly dispersed on the surface of alumina. The carbon nanotubes produced by the catalysts prepared by impregnation method are flatter and have less impurities. The ratio of ID/IG+ is 29.7% lower than that of the sol-gel method in the Raman spectra. The TEM statistics show that the average diameter of the carbon tubes decreases by 23.3%. Therefore, the impregnation method can improve the quality of carbon nanotubes in the case of a similar degree of difficulty in the preparation of the catalyst.