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1

Determination of carmine food dye (E120) in foodstuffs by stripping voltammetry.  

PubMed

The behavior of the food colorant agent carmine (E120) was studied by square-wave adsorptive stripping voltammetry (SW-AdSV) at the hanging mercury drop electrode. It was observed that carmine gave a sensitive stripping voltammetric peak at -350 mV in pH 3 acetate buffer. The cyclic voltammetric technique was also used to characterize the electrochemical reduction process of carmine. The adsorptive voltammetric signal was evaluated with respect to various experimental conditions, and the optimized values were supporting electrolyte, acetate buffer; buffer acidity, pH 3; dye concentration, 3 x 10(-7) M; accumulation time, 150 s; accumulation potential, -0.2 V; scan rate, 300 mV/s; pulse amplitude, 185 mV; SW frequency, 20 Hz; working electrode area, 0.6 mm2; and convection rate, 2600 rpm. The SW-AdSV peak currents depended linearly on the concentration of carmine from 5 x 10(-8) to 1.25 x 10(-7) mol/L (r = 0.99). A detection limit of 1.43 x 10(-9) mol/L with an RSD of 2.2% and a mean recovery of 97.9% were obtained. Possible interferences by several substances usually present in food products such as food additive dyes (E102, E100, E123, E127, and E129), artificial sweeteners, preservatives, and antioxidants were also evaluated. The proposed electrochemical procedure was successfully applied to the determination of carmine food dye in spiked commercially available ice cream and soft drinks. PMID:19916383

Alghamdi, Ahmad H; Alshammery, Hamed M; Abdalla, Mohamed A; Alghamdi, Ali F

2009-01-01

2

Batch and bulk removal of hazardous dye, indigo carmine from wastewater through adsorption.  

PubMed

An inexpensive adsorption method has been developed for the removal of indigo carmine, a highly toxic indigoid class of dye from wastewater. Waste materials--bottom ash, a power plant waste and de-oiled soya, an agricultural waste--have been used as adsorbents. Attempts have been made through batch and bulk removal of the dye and both the adsorbents have been found to exhibit good efficiency to adsorb indigo carmine. Under batch technique effect of temperature, pH, concentration, dosage of adsorbents, sieve size of adsorbents, etc. have been observed. The dye uptake on to both the adsorbents is found to validate Langmuir and Freundlich adsorption isotherms models. Different thermodynamic parameters, like Gibb's free energy, enthalpy and entropy of the on-going adsorption process have also been evaluated. Batch technique has also been employed for the kinetic measurements and the adsorption follows a first order rate kinetics for both the adsorbents. The kinetic investigations also reveal for both the adsorbents film diffusion and particle diffusion mechanisms are operative in the lower and higher concentration ranges, respectively. Under the bulk removal, indigo carmine has been adsorbed through the column beds of bottom ash and de-oiled soya and more than 90% of the dye material has been recovered by eluting dilute NaOH solution through exhausted columns. PMID:16687210

Mittal, Alok; Mittal, Jyoti; Kurup, Lisha

2006-09-01

3

Rice husk ash as an effective adsorbent: evaluation of adsorptive characteristics for Indigo Carmine dye.  

PubMed

Present study explored the adsorptive characteristics of Indigo Carmine (IC) dye from aqueous solution onto rice husk ash (RHA). Batch experiments were carried out to determine the influence of parameters like initial pH (pH(0)), contact time (t), adsorbent dose (m) and initial concentration (C(0)) on the removal of IC. The optimum conditions were found to be: pH(0)=5.4, t=8h and m=10.0 g/l. The pseudo-second-order kinetic model represented the adsorption kinetics of IC on to RHA. Equilibrium isotherms were analyzed by Freundlich, Langmuir, Temkin and Redlich-Peterson models using a non-linear regression technique. Adsorption of IC on RHA was favorably influenced by an increase in the temperature of the operation. The positive values of the change in entropy (DeltaS(0)) and heat of adsorption (DeltaH(0)); and the negative value of change in Gibbs free energy (DeltaG(0)) indicate feasible and spontaneous adsorption of IC on to RHA. PMID:18289771

Lakshmi, Uma R; Srivastava, Vimal Chandra; Mall, Indra Deo; Lataye, Dilip H

2009-02-01

4

Raman spectroscopy of organic dyes adsorbed on pulsed laser deposited silver thin films  

NASA Astrophysics Data System (ADS)

The results of a surface-enhanced Raman scattering (SERS) study performed on representative organic and inorganic dyes adsorbed on silver nanostructured thin films are presented and discussed. Silver thin films were deposited on glass slides by focusing the beam from a KrF excimer laser (wavelength 248 nm, pulse duration 25 ns) on a silver target and performing the deposition in a controlled Ar atmosphere. Clear Raman spectra were acquired for dyes such as carmine lake, garanza lake and brazilwood overcoming their fluorescence and weak Raman scattering drawbacks. UV-visible absorption spectroscopy measurements were not able to discriminate among the different chromophores usually referred as carmine lake (carminic, kermesic and laccaic acid), as brazilwood (brazilin and brazilein) and as garanza lake (alizarin and purpurin). SERS measurements showed that the analyzed samples are composed of a mixture of different chromophores: brazilin and brazilein in brazilwood, kermesic and carminic acid in carmine lake, alizarin and purpurin in garanza lake. Detection at concentration level as low as 10-7 M in aqueous solutions was achieved. Higher Raman intensities were observed using the excitation line of 632.8 nm wavelength with respect to the 785 nm, probably due to a pre-resonant effect with the molecular electronic transitions of the dyes.

Fazio, E.; Neri, F.; Valenti, A.; Ossi, P. M.; Trusso, S.; Ponterio, R. C.

2013-08-01

5

Intraoperative stereotactic injection of Indigo Carmine dye to mark ill-defined tumor margins: a prospective Phase I-II study.  

PubMed

OBJECT A critical goal in neurosurgical oncology is maximizing the extent of tumor resection while minimizing the risk to normal white matter tracts. Frameless stereotaxy and white matter mapping are indispensable tools in this effort, but deep tumor margins may not be accurately defined because of the "brain shift" at the end of the operation. The authors investigated the safety and efficacy of a technique for marking the deep margins of intraaxial tumors with stereotactic injection of Indigo Carmine dye. METHODS Investigational New Drug study approval for a prospective study in adult patients with gliomas was obtained from the FDA (Investigational New Drug no. 112680). At surgery, 1-3 stereotactic injections of 0.01 ml of Indigo Carmine dye were performed through the initial bur holes into the deep tumor margins before elevation of the bone flap. White light microscopic resection was conducted in standard fashion by using frameless stereotactic navigation until the injected margins were identified. The resection of the injected tumor margins and the extent of resection of the whole tumor volume were determined by using postoperative volumetric MRI. RESULTS In total 17 injections were performed in 10 enrolled patients (6 male, 4 female), whose mean age was 49 years. For all patients, the injection points were identified intraoperatively and tumor was resected at these points. The staining pattern was reproducible; it was a sphere of stained tissue approximately 5 mm in diameter. A halo of stained tissue and a backflow of dye through the needle tract were also noted, but these were clearly distinct from the staining pattern of the injection point, which was vividly colored and demarcated. Postoperative MR images verified the resection of all injection points. The mean extent of resection of the tumor as a whole was 97.1%. For 1 patient, a brain abscess developed on postoperative Day 16 and needed additional surgical treatment. CONCLUSIONS Stereotactic injection of Indigo Carmine dye can be used to demarcate multiple deep tumor margins, which can be readily identified intraoperatively by using standard white light microscopy. This technique may enhance the accuracy of frameless stereotactic navigation and increase the extent of resection of intraaxial tumors. PMID:25361489

Margetis, Konstantinos; Rajappa, Prajwal; Tsiouris, Apostolos John; Greenfield, Jeffrey P; Schwartz, Theodore H

2015-01-01

6

Prospects for Organic Dye Nanoparticles  

Microsoft Academic Search

\\u000a \\u000a AbstractA review of organic nanoparticles consisting of small functional dye molecules is presented in this chapter. The study of\\u000a organic dye nanoparticles does not have a lengthy history, but there is growing scientific and technological interest owing\\u000a to their special characteristics: physicochemical properties of organic dye nanoparticles considerably differ not only from\\u000a those of individual molecules due to the presence

Hiroshi Yao

7

Environmentally Friendly Natural Dyeing of Organic Cotton  

Microsoft Academic Search

In this study, organic cotton fabrics were dyed with different natural dye sources (madder root, walnut shell, henna, horse chestnut, pomegranate peel, berberis vulgaris root, thyme, and sage tea). The dyeing was carried out with different mordants (copper sulphate, potassium aluminum sulphate, potassium tartrate, and citric acid), using pre-mordanting dyeing methods. The color of the fabrics was investigated in terms

Mustafa Tutak; N. Ebru Korkmaz

2012-01-01

8

ORGANIC DYES AND PIGMENTS DATA BASE  

EPA Science Inventory

The objective of this research program was to compile a data base covering all the commercially significant dyes and pigments produced or imported in the United States. The Organic Dyes and Pigments Data Base (ODPDB) contains the following data elements: chemical-related data (co...

9

The Presentation Carmine Gallo  

E-print Network

The Presentation Secrets of Steve Jobs Carmine Gallo Columnist, BusinessWeek.com #12;B 10 Ways to Sell Your Ideas the Steve Jobs Way.............................................................................................................................................................................11 Table of Contents #12;1 10 Ways to Sell Your Ideas the Steve Jobs Way! In The Presentation Secrets

10

Organic Dyes, Conjugation, and the Chemistry of Vision  

E-print Network

Organic Dyes, Conjugation, and the Chemistry of Vision François G. Amar Department of Chemistry blue light on a yellow solution and no light gets through: #12;Organic dyes are conjugated molecules) = 165 217 286 345 #12;Some other organic dyes O OH OH HO OH OH N+ N CH NH2 H3C N CH3 H Mauve: the first

Amar, François G.

11

Continuous-wave organic dye lasers and methods  

DOEpatents

An organic dye laser produces a continuous-wave (cw) output without any moving parts (e.g., without using flowing dye streams or spinning discs of solid-state dye media to prevent photobleaching) and with a pump beam that is stationary with respect to the organic dye medium. The laser's resonant cavity, organic dye medium, and pump beam are configured to excite a lasing transition over a time scale longer than the associated decay lifetimes in the organic dye medium without photobleaching the organic dye medium. Because the organic dye medium does not photobleach when operating in this manner, it may be pumped continuously so as to emit a cw output beam. In some examples, operation in this manner lowers the lasing threshold (e.g., to only a few Watts per square centimeter), thereby facilitating electrical pumping for cw operation.

Shapira, Ofer; Chua, Song-Liang; Zhen, Bo; Lee, Jeongwon; Soljacic, Marin

2014-09-16

12

Organic dyes based on fluorene and its derivatives  

NASA Astrophysics Data System (ADS)

Data on various types of organic dyes based on fluorene and its derivatives, including polymethine, styryl, triphenylmethane, spiran, merocyanine, porphyrin and polymeric dyes, as well as azo dyes and donor-acceptor polyenes, are described systematically. The key methods for their synthesis are considered. The properties of the dyes are analyzed and summarized. The principles of development of modern functional materials based on these dyes are outlined. The use of these materials in advanced fields of science and technology such as photovoltaics, electroluminescence, nonlinear optics, holography, sensing photodynamic therapy are considered. The bibliography includes 476 references.

Kurdyukova, I. V.; Ishchenko, Aleksandr A.

2012-03-01

13

Structure of acid-stable carmine.  

PubMed

Acid-stable carmine has recently been distributed in the U.S. market because of its good acid stability, but it is not permitted in Japan. We analyzed and determined the structure of the major pigment in acid-stable carmine, in order to establish an analytical method for it. Carminic acid was transformed into a different type of pigment, named acid-stable carmine, through amination when heated in ammonia solution. The features of the structure were clarified using a model compound, purpurin, in which the orientation of hydroxyl groups on the A ring of the anthraquinone skeleton is the same as that of carminic acid. By spectroscopic means and the synthesis of acid-stable carmine and purpurin derivatives, the structure of the major pigment in acid-stable carmine was established as 4-aminocarminic acid, a novel compound. PMID:11998314

Sugimoto, Naoki; Kawasaki, Yoko; Sato, Kyoko; Aoki, Hiromitsu; Ichi, Takahito; Koda, Takatoshi; Yamazaki, Takeshi; Maitani, Tamio

2002-02-01

14

Suspended-core optical fibres for organic dye absorption spectroscopy  

NASA Astrophysics Data System (ADS)

In this paper, we report on our study of UV-VIS absorption spectroscopy in suspended-core optical fibres (SCFs) filled with organic-dye solutions. We compare two different dye classes, the anionic dye - bromophenol blue sodium salt (BB) and cationic dye - oxazine 725 perchlorate (OX). While the results obtained with BB are in a good agreement with the spectra measured in a standard reference cuvette, those obtained with OX are different and reveal much stronger absorption of light than in cuvettes. This stronger absorption indicates accumulation of the dye molecules on the short section of the core close to the end of the fibre. This observation demonstrates difference in physicochemical properties of the two dye classes and is important for the development of chemical sensors based on SCFs.

Wajnchold, Barbara; Umi?ska, Ada; Grabka, Micha?; Kotas, Dariusz; Pustelny, Szymon; Gawlik, Wojciech

2013-05-01

15

Organic dyes containing fluorene decorated with imidazole units for dye-sensitized solar cells.  

PubMed

New organic dyes containing fluorene functionalized with two imidazole chromophores as donors and cyanoacrylic acid acceptors have been synthesized and successfully demonstrated as sensitizers in nanocrystalline TiO2-based dye-sensitized solar cells (DSSCs). The monoimidazole analogues were also synthesized for comparison. The Sommelet reaction of bromomethylated 2-bromo-9,9-diethyl-9H-fluorene produced the key precursor 7-bromo-9,9-diethyl-9H-fluorene-2,4-dicarbaldehyde required for the preparation of imidazole-functionalized fluorenes. Since the dyes possess weak donor segment, the electron-richness of the conjugation pathway dictated the optical, electrochemical, and photovoltaic properties of the dyes. The dyes served as sensitizers in DSSC and exhibited moderate efficiency up to 3.44%. The additional imidazole present on the fluorene has been found to retard the electron recombination due to the bulkier hydrophobic environment and led to high open-circuit voltage in the devices. PMID:24628443

Kumar, Dhirendra; Thomas, K R Justin; Lee, Chuan-Pei; Ho, Kuo-Chuan

2014-04-01

16

Near-infrared fluorescence imaging using organic dye nanoparticles.  

PubMed

Near-infrared (NIR) fluorescence imaging in the 700-1000 nm wavelength range has been very attractive for early detection of cancers. Conventional NIR dyes often suffer from limitation of low brightness due to self-quenching, insufficient photo- and bioenvironmental stability, and small Stokes shift. Herein, we present a strategy of using small-molecule organic dye nanoparticles (ONPs) to encapsulate NIR dyes to enable efficient fluorescence resonance energy transfer to obtain NIR probes with remarkably enhanced performance for in vitro and in vivo imaging. In our design, host ONPs are used as not only carriers to trap and stabilize NIR dyes, but also light-harvesting agent to transfer energy to NIR dyes to enhance their brightness. In comparison with pure NIR dyes, our organic dye nanoparticles possess almost 50-fold increased brightness, large Stokes shifts (?250 nm) and dramatically enhanced photostability. With surface modification, these NIR-emissive organic nanoparticles have water-dispersity and size- and fluorescence- stability over pH values from 2 to 10 for almost 60 days. With these superior advantages, these NIR-emissive organic nanoparticles can be used for highly efficient folic-acid aided specific targeting in vivo and ex vivo cellular imaging. Finally, during in vivo imaging, the nanoparticles show negligible toxicity. Overall, the results clearly display a potential application of using the NIR-emissive organic nanoparticles for in vitro and in vivo imaging. PMID:24461324

Yu, Jia; Zhang, Xiujuan; Hao, Xiaojun; Zhang, Xiaohong; Zhou, Mengjiao; Lee, Chun-Sing; Chen, Xianfeng

2014-03-01

17

Vermicompost for Tinted Organic Cationic Dyes Retention  

Microsoft Academic Search

The use of vermicompost was expanded as natural adsorbent for cationic dyes retention. The adsorption profiles in batch and\\u000a flow modes for crystal violet and methylene blue on vermicompost material were evaluated. In batch mode, a retention index\\u000a higher than 97% was obtained for both compounds, while in flow condition, 40g of dried adsorbent material were enough to\\u000a remove 100mg

Madson de Godoi Pereira; Mauro Korn; Bruno Barros Santos; Marcia Guia Ramos

2009-01-01

18

Structure-performance correlations of organic dyes with an electron-deficient diphenylquinoxaline moiety for dye-sensitized solar cells.  

PubMed

The high performances of dye-sensitized solar cells (DSSCs) based on seven new dyes are disclosed. Herein, the synthesis and electrochemical and photophysical properties of a series of intentionally designed dipolar organic dyes and their application in DSSCs are reported. The molecular structures of the seven organic dyes are composed of a triphenylamine group as an electron donor, a cyanoacrylic acid as an electron acceptor, and an electron-deficient diphenylquinoxaline moiety integrated in the ?-conjugated spacer between the electron donor and acceptor moieties. The DSSCs based on the dye DJ104 gave the best overall cell performance of 8.06?%; the efficiency of the DSSC based on the standard N719 dye under the same experimental conditions was 8.82?%. The spectral coverage of incident photon-to-electron conversion efficiencies extends to the onset at the near-infrared region due to strong internal charge-transfer transition as well as the effect of electron-deficient diphenylquinoxaline to lower the energy gap in these organic dyes. A combined tetraphenyl segment as a hydrophobic barrier in these organic dyes effectively slows down the charge recombination from TiO2 to the electrolyte and boosts the photovoltage, comparable to their Ru(II) counterparts. Detailed spectroscopic studies have revealed the dye structure-cell performance correlations, to allow future design of efficient light-harvesting organic dyes. PMID:25042065

Li, Sie-Rong; Lee, Chuan-Pei; Yang, Po-Fan; Liao, Chia-Wei; Lee, Mandy M; Su, Wei-Lin; Li, Chun-Ting; Lin, Hao-Wu; Ho, Kuo-Chuan; Sun, Shih-Sheng

2014-08-01

19

Co-sensitization of organic dyes for efficient dye-sensitized solar cells.  

PubMed

Novel cyanine dyes, in which a tetrahydroquinoline derivative is used as an electron donor and 1-butyl-5-carboxy-3, 3-dimethyl-indol-1-ium moiety is used as an electron acceptor and anchoring group, were designed and synthesized for application in dye-sensitized solar cells. The photovoltaic performance of these solar cells depends markedly on the molecular structure of the dyes in terms of the n-hexyl chains and the methoxyl unit. Retardation of charge recombination caused by the introduction of n-hexyl chains resulted in an increase in electron lifetime. As a consequence, an improvement of open-circuit photovoltage (V(oc)) was achieved. Also, the electron injection efficiencies were improved by the introduction of methoxyl moiety, which led to a higher short-circuit photocurrent density (J(sc)). The highest average efficiency of the sensitized devices (?) was 5.6% (J(sc)=13.3 mA cm(-2), V(oc)=606 mV, and fill factor FF=69.1%) under 100 mW cm(-2) (AM 1.5G) solar irradiation. All of these dyes have very high absorption extinction coefficients and strong absorption in a relatively narrow spectrum range (500-650 nm), so one of our organic dyes was explored as a sensitizer in co-sensitized solar cells in combination with the other two other existing organic dyes. Interestingly, a considerably improved photovoltaic performance of 8.2% (J(sc)=20.1 mA cm(-2), V(oc)=597 mV, and FF=68.3%) was achieved and the device showed a panchromatic response with a high incident photon-to-current conversion efficiency exceeding 85% in the range of 400-700 nm. PMID:23193040

Cheng, Ming; Yang, Xichuan; Li, Jiajia; Zhang, Fuguo; Sun, Licheng

2013-01-01

20

Photoproducts of carminic acid formed by a composite from Manihot dulcis waste.  

PubMed

Carbon-TiO2 composites were obtained from carbonised Manihot dulcis waste and TiO2 using glycerol as an additive and thermally treating the composites at 800 C. Furthermore, carbon was obtained from manihot to study the adsorption, desorption and photocatalysis of carminic acid on these materials. Carminic acid, a natural dye extracted from cochineal insects, is a pollutant produced by the food industry and handicrafts. Its photocatalysis was observed under different atmospheres, and kinetic curves were measured by both UV-Vis and HPLC for comparison, yielding interesting differences. The composite was capable of decomposing approximately 50% of the carminic acid under various conditions. The reaction was monitored by UV-Vis spectroscopy and LC-ESI-(Qq)-TOF-MS-DAD, enabling the identification of some intermediate species. The deleterious compound anthracene-9,10-dione was detected both in N2 and air atmospheres. PMID:25466082

Antonio-Cisneros, Cynthia M; Dvila-Jimnez, Martn M; Elizalde-Gonzlez, Mara P; Garca-Daz, Esmeralda

2015-04-15

21

Organics Verification Study for Sinclair and Dyes Inlets, Washington  

SciTech Connect

Sinclair and Dyes Inlets near Bremerton, Washington, are on the State of Washington 1998 303(d) list of impaired waters because of fecal coliform contamination in marine water, metals in sediment and fish tissue, and organics in sediment and fish tissue. Because significant cleanup and source control activities have been conducted in the inlets since the data supporting the 1998 303(d) listings were collected, two verification studies were performed to address the 303(d) segments that were listed for metal and organic contaminants in marine sediment. The Metals Verification Study (MVS) was conducted in 2003; the final report, Metals Verification Study for Sinclair and Dyes Inlets, Washington, was published in March 2004 (Kohn et al. 2004). This report describes the Organics Verification Study that was conducted in 2005. The study approach was similar to the MVS in that many surface sediment samples were screened for the major classes of organic contaminants, and then the screening results and other available data were used to select a subset of samples for quantitative chemical analysis. Because the MVS was designed to obtain representative data on concentrations of contaminants in surface sediment throughout Sinclair Inlet, Dyes Inlet, Port Orchard Passage, and Rich Passage, aliquots of the 160 MVS sediment samples were used in the analysis for the Organics Verification Study. However, unlike metals screening methods, organics screening methods are not specific to individual organic compounds, and are not available for some target organics. Therefore, only the quantitative analytical results were used in the organics verification evaluation. The results of the Organics Verification Study showed that sediment quality outside of Sinclair Inlet is unlikely to be impaired because of organic contaminants. Similar to the results for metals, in Sinclair Inlet, the distribution of residual organic contaminants is generally limited to nearshore areas already within the actively managed Puget Sound Naval Shipyard and Intermediate Maintenance Facility Superfund Site, where further source-control actions and monitoring are under way.

Kohn, Nancy P.; Brandenberger, Jill M.; Niewolny, Laurie A.; Johnston, Robert K.

2006-09-28

22

21 CFR 73.2087 - Carmine.  

Code of Federal Regulations, 2010 CFR

...GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION...specifications. The color additive carmine shall conform...amounts consistent with good manufacturing practices. (c) Labeling. The color additive and any mixture...

2010-04-01

23

21 CFR 73.2087 - Carmine.  

Code of Federal Regulations, 2011 CFR

...GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION...specifications. The color additive carmine shall conform...consistent with good manufacturing practices. (c) Labeling . (1) The color additive and any mixture...

2011-04-01

24

21 CFR 73.2087 - Carmine.  

Code of Federal Regulations, 2013 CFR

...GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION...specifications. The color additive carmine shall conform...consistent with good manufacturing practices. (c) Labeling . (1) The color additive and any mixture...

2013-04-01

25

21 CFR 73.2087 - Carmine.  

Code of Federal Regulations, 2014 CFR

...GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION...specifications. The color additive carmine shall conform...consistent with good manufacturing practices. (c) Labeling. (1) The color additive and any mixture...

2014-04-01

26

21 CFR 73.2087 - Carmine.  

Code of Federal Regulations, 2012 CFR

...GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION...specifications. The color additive carmine shall conform...consistent with good manufacturing practices. (c) Labeling . (1) The color additive and any mixture...

2012-04-01

27

Occupational Asthma to Carmine in a Butcher  

Microsoft Academic Search

Hypersensitivity to carmine (E120) has been identified as a cause of food intolerance and occupational asthma. We present a case of occupational asthma following exposure to carmine in a manufacturer of sausages and review the literature. Case Report: A 42-year-old non-atopic male presented with a 5-year history of rhinoconjunctivitis and asthma on occupational exposure to food additive dusts. Symptoms increased

ngel Ferrer; Francisco M. Marco; Carmen Andreu; Jos M. Sempere

2005-01-01

28

Altering the self-organization of dyes on titania with dyeing solvents to tune the charge-transfer dynamics of sensitized solar cells.  

PubMed

Herein we selected the model organic donor-acceptor dye C218 and modulated the self-organization of dye molecules on the surface of titania by changing the dyeing solvent from chlorobenzene to a mixture of acetonitrile and tert-butanol. We further unveiled the relationship between the microstructure of a dye layer and the multichannel charge-transfer dynamics that underlie the photovoltaic performance of dye-sensitized solar cells. PMID:24375950

Wang, Yinglin; Yang, Lin; Zhang, Jing; Li, Renzhi; Zhang, Min; Wang, Peng

2014-04-14

29

Theoretical design of thiazolothiazole-based organic dyes with different electron donors for dye-sensitized solar cells.  

PubMed

In this study, we have designed four novel organic donor-?-acceptor dyes (D1, D2, D3, D4), used for dye sensitized solar cells (DSSCs). The electron acceptor (anchoring) group was 2-cyanoacrylic for all dyes whereas the electron donor unit varied (coumarin, indoline, carbazole, triphenylamine) and the influence was investigated. These dyes, based on thiazolothiazole as ?-spacer, were studied by density functional theory (DFT) and its extensible time dependant DFT (TDDFT) approaches to shed light on how the ?-conjugation order influence the performance of the dyes in the DSSCs. The theoretical results have shown that the LUMO and HOMO energy levels of these dyes can be ensuring positive effect on the process of electron injection and dye regeneration. The trend of the calculated HOMO-LUMO gaps nicely compares with the spectral data. Key parameters in close connection with the short-circuit current density (Jsc), including light harvesting efficiency (LHE), injection driving force (?Ginject.) and total reorganization energy (?total), were discussed. The calculated results of these dyes reveal that dye D2, with indoline as electron donor group, can be used as a potential sensitizer for TiO2 nanocrystalline solar cells due to its best electronic and optical properties and good photovoltaic parameters. PMID:24866090

Fitri, Asmae; Benjelloun, Adil Touimi; Benzakour, Mohammed; Mcharfi, Mohammed; Hamidi, Mohammed; Bouachrine, Mohammed

2014-11-11

30

Theoretical design of thiazolothiazole-based organic dyes with different electron donors for dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

In this study, we have designed four novel organic donor-?-acceptor dyes (D1, D2, D3, D4), used for dye sensitized solar cells (DSSCs). The electron acceptor (anchoring) group was 2-cyanoacrylic for all dyes whereas the electron donor unit varied (coumarin, indoline, carbazole, triphenylamine) and the influence was investigated. These dyes, based on thiazolothiazole as ?-spacer, were studied by density functional theory (DFT) and its extensible time dependant DFT (TDDFT) approaches to shed light on how the ?-conjugation order influence the performance of the dyes in the DSSCs. The theoretical results have shown that the LUMO and HOMO energy levels of these dyes can be ensuring positive effect on the process of electron injection and dye regeneration. The trend of the calculated HOMO-LUMO gaps nicely compares with the spectral data. Key parameters in close connection with the short-circuit current density (Jsc), including light harvesting efficiency (LHE), injection driving force (?Ginject.) and total reorganization energy (?total), were discussed. The calculated results of these dyes reveal that dye D2, with indoline as electron donor group, can be used as a potential sensitizer for TiO2 nanocrystalline solar cells due to its best electronic and optical properties and good photovoltaic parameters.

Fitri, Asmae; Benjelloun, Adil Touimi; Benzakour, Mohammed; Mcharfi, Mohammed; Hamidi, Mohammed; Bouachrine, Mohammed

2014-11-01

31

Adsorption of indigo carmine from aqueous solution using coal fly ash and zeolite from fly ash  

Microsoft Academic Search

Coal fly ash, a waste generated at the Figueira coal-fired electric power plant located in Brazil, was used to synthesize\\u000a zeolite by hydrothermal treatment with NaOH solution at 100C for 24h. The fly ash (FA) and this synthesized zeolite (ZM)\\u000a that was characterized predominantly as hydroxy-sodalite were used as adsorbents for anionic dye indigo carmine from aqueous\\u000a solutions. The samples

Terezinha E. M. de Carvalho; Denise A. Fungaro; Carina P. Magdalena; Patricia Cunico

32

Removal of Indigo Carmine and Pb(II) Ion from Aqueous Solution by Polyaniline  

Microsoft Academic Search

In this work, we report the synthesis of polyaniline emaraldine salt (PAni-ES) by a chemical oxidative polymerization method. The obtained PAni-ES samples prepared under different conditions were used for the removal of indigo carmine anionic dye and Pb(II) ion from aqueous solutions. The results also showed that the pseudosecond-order kinetic model fitted better than the data obtained from pseudofirst-order model

Murat Ya?ar; Hseyin Deligz; Gamze Gl

2011-01-01

33

Triphenylamine-based organic dyes with julolidine as the secondary electron donor for dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

Two novel donor-donor-?-conjugated-acceptor (D-D-?-A) metal-free organic dyes (JTPA1 and JTPA2) with a julolidine moiety as the secondary electron donor for dye-sensitized solar cells (DSSCs) are synthesized. Their absorption spectra, electrochemical and photovoltaic properties are extensively investigated and compared with TPA2 dye. Transient absorption measurements show that both sensitizers are quickly regenerated and the dye cations are efficiently intercepted by the redox mediator. Both dyes show good performance as DSSC photosensitizers. In particular, a DSSC using JTPA2 with rhodanine-3-acetic acid shows better photovoltaic performance with a short-circuit photocurrent density (Jsc) of 9.30 mA cm-2, an open-circuit photovoltage (Voc) of 509 mV and a fill factor (FF) of 0.68, corresponding to an overall conversion efficiency (?) of 3.2% under AM 1.5 irradiation (100 mW cm-2). Under similar test conditions, ruthenium-based N719 dye gives an efficiency of 6.7%. Compared to TPA2, the dye regeneration rate, the short-circuit photocurrent density and the conversion efficiency of JTPA2 are doubled by introducing a julolidine unit. Our findings show that the julolidine unit may be an excellent electron donor system for organic dyes harvesting solar irradiation.

Wu, Guohua; Kong, Fantai; Li, Jingzhe; Fang, Xiaqin; Li, Yi; Dai, Songyuan; Chen, Qianqian; Zhang, Xianxi

2013-12-01

34

Holographic investigation of DNA activated by organic dyes  

NASA Astrophysics Data System (ADS)

The present work is devoted to investigation of holographic recording features in medium composed of bipolymer film of DNA, sensitized by organic dyes to He-Ne and YAG-Nd lasers radiation. Two types of holograms formed in the system of dye-DNA by two different modes of recording were studied: (1) transmission holograms recorded by a stationary He-Ne-laser with diffraction efficiency of order 0.02%. (2) Relief-phase holograms (RPH) recorded by a pulse YAG-Nd laser with a diffraction efficiency of order 5%. Despite distinction in efficiency and recording mechanisms the explored holograms are combined by one general property -- they disappear spontaneously during the few hours. The results of the work allow to make conclusions about mechanisms of recording and erasure of holograms, as well as to determine diffusion coefficients in dry film of DNA at a room temperature.

Lantukh, Yu. D.; Ketsle, G. A.; Letuta, S. N.; Pashkevitch, S. N.; Alidzhanov, E. K.; Ipatov, I. V.

2005-02-01

35

A novel 2,7-diaminofluorene-based organic dye for a dye-sensitized solar cell  

NASA Astrophysics Data System (ADS)

A novel 2,7-diaminofluorene-based organic dye (coded as JD2) with the diarylaminofluorene unit as the electron donor and the cyanoacrylic acid as the acceptor as well as anchoring group in a donor-?-donor-?-acceptor architecture is used in a dye-sensitized solar cell (DSSC). The TiO2 film thickness and the dye soaking time are optimized, and a coadsorbate of bis-(3,3-dimethyl-butyl)-phosphinic acid (DINHOP) is added to the dye solution to reform the cell performance. Effects of the additives, N-methylbenzimidazole (NMBI), guanidinium thiocyanate (GuSCN) or 4-tert-butylpyridine (TBP) in the electrolyte on the photovoltaic performance of the DSSC are studied. Effects of change of DINHOP concentration in JD2 dye solution, change of ratio of LiI to 1,2-dimethyl-3-propylimidazolium iodide (DMPII), and change of concentration of I2 in the electrolyte on the photovoltaic performance of the DSSC are studied. A light-to-electricity conversion efficiency (?) of 6.31% is achieved for the JD2 dye-based DSSC, which is one of the best efficiencies for a cell with an organic dye. Explanations are made with electrochemical impedance spectra (EIS), laser-induced photo-voltage transients, and incident photo-to-current conversion efficiency (IPCE) curves.

Lin, Lu-Yin; Lee, Chuan-Pei; Yeh, Min-Hsin; Baheti, Abhishek; Vittal, R.; Thomas, K. R. Justin; Ho, Kuo-Chuan

2012-10-01

36

Probing the regeneration process of triphenylamine-based organic dyes in dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

The regeneration processes of triphenylamine (TPA)-based dyes with cobalt redox mediator in dye-sensitized solar cells (DSSCs) have been investigated using density functional theory combined with the Marcus theory of electron transfer. Our results show that with the extension or rigidification of the oligothiophene conjugation linker the absorption spectra of TPA dyes exhibit observable red-shift in the maximum absorbance that favors light-harvesting, while the electron transfer rates for dye regeneration decrease in some degrees due to the increased activation free energies and the reduced electronic coupling energies which hampers the dye regeneration. Importantly, the undesirable influences on dye regeneration by extending the linker moiety are more significant than that by the way of rigidification. Thus, the rigidification is a better choice than the extension of the conjugated moiety for the design of D-?-A type dyes based on the properties of light-harvesting and the kinetics of dye regeneration.

Sun, Zhu-Zhu; Li, Quan-Song; Sun, Ping-Ping; Li, Ze-Sheng

2015-02-01

37

Interaction of protonated merocyanine dyes with amines in organic solvents  

NASA Astrophysics Data System (ADS)

2,6-Diphenyl-4-(2,4,6-triphenylpyridinium-1-yl)phenolate ( 1a) and 4-[(1-methyl-4(1 H)-pyridinylidene)-ethylidene]-2,5-cyclohexadien-1-one ( 2a) were protonated in organic solvents (dichloromethane, acetonitrile, and DMSO) to form 1b and 2b, respectively. The appearance of the solvatochromic bands of 1a and 2a was studied UV-vis spectrophotometrically by deprotonation of 1b and 2b in solution in the presence of the following amines: aniline (AN), N-methylaniline (NMAN), N, N-dimethylaniline (NDAN), n-butylamine (BA), diethylamine (DEA), and triethylamine (TEA). Titrations of 1b and 2b with the amines were carried out and the binding constants were determined from the titration curves in each solvent, using a mathematical model adapted from the literature which considers the simultaneous participation of two dye: amine stoichiometries, 1:1 and 1:2. The data obtained showed the following base order for the two compounds in DMSO: BA > DEA > TEA, while aromatic amines did not cause any effect. In dichloromethane, the following base order for 1b was verified: TEA > DEA > BA ?NDAN, while for 2b the order was: TEA > DEA > BA, suggesting that 1b is more acidic than 2b. The data in acetonitrile indicated for 1b and 2b the following order for the amines: DEA > TEA > BA. The diversity of the experimental data were explained based on a model that considers the level of interaction of the protonated dyes with the amines to be dependent on three aspects: (a) the basicity of the amine, which varies according to their molecular structure and the solvent in which it is dissolved, (b) the molecular structure of the dye, and (c) the solvent used to study the system.

Ribeiro, Eduardo Alberton; Sidooski, Thiago; Nandi, Leandro Guarezi; Machado, Vanderlei Gageiro

2011-10-01

38

Insights into aggregation effects on optical property and electronic coupling of organic dyes in dye sensitized solar cells  

NASA Astrophysics Data System (ADS)

Combining density functional theory (DFT), time-dependent DFT, and density functional tight binding (DFTB) methods, we present a computational investigation on the aggregation effects of two organic dyes, WS-2 and WS-6, which are used as sensitizers in dye sensitized solar cells (DSSCs). The calculated absorption and emission spectra in solution and on TiO2 agree well with the experimental observations, which demonstrate WS-6 is less prone to aggregation due to a hexyl substituent on the thiophene ring compared to WS-2. Importantly, our results predict strong aggregation interactions inducing larger electronic coupling between the stacking dimers, which may be detrimental for electronic injection from dye to TiO2 and partly responsible for the loss of photo-voltaic efficiency. The deeper understanding of the dye aggregation effects shed lights on a better knowledge about the complex factors determining the function of DSSC and rational design of high efficiency sensitizers.

Feng, Shuai; Li, Quan-Song; Yang, Li-Na; Sun, Zhu-Zhu; Niehaus, Thomas A.; Li, Ze-Sheng

2015-01-01

39

Catalytic degradation of organic dyes using biosynthesized silver nanoparticles.  

PubMed

The green synthesis of metallic nanoparticles paved the way to improve and protect the environment by decreasing the use of toxic chemicals and eliminating biological risks in biomedical applications. Plant mediated synthesis of metal nanoparticles is gaining more importance owing to its simplicity, rapid rate of synthesis of nanoparticles and eco-friendliness. The present article reports an environmentally benign and unexploited method for the synthesis of silver nanocatalysts using Trigonella foenum-graecum seeds, which is a potential source of phytochemicals. The UV-visible absorption spectra of the silver samples exhibited distinct band centered around 400-440 nm. The major phytochemicals present in the seed extract responsible for the formation of silver nanocatalysts are identified using FTIR spectroscopy. The report emphasizes the effect of the size of silver nanoparticles on the degradation rate of hazardous dyes, methyl orange, methylene blue and eosin Y by NaBH4. The efficiency of silver nanoparticles as a promising candidate for the catalysis of organic dyes by NaBH4 through the electron transfer process is established in the present study. PMID:24210247

Vidhu, V K; Philip, Daizy

2014-01-01

40

Organic dyes with intense light absorption especially suitable for application in thin-layer dye-sensitized solar cells.  

PubMed

Three new thiazolo[5,4-d]thiazole-based organic dyes have been designed and synthesized for employment as DSSC sensitizers. Alternation of the electron poor thiazolothiazole unit with two propylenedioxythiophene (ProDOT) groups ensured very intense light absorption in the visible region (? up to 9.41 10(4) M(-1) cm(-1) in THF solution). The dyes were particularly suitable for application in transparent and opaque thin-layer DSSCs (TiO2 thickness: 5.5-6.5 ?m, efficiencies up to 7.71%), thus being good candidates for production of solar cells under simple fabrication conditions. PMID:25264863

Dess, Alessio; Calamante, Massimo; Mordini, Alessandro; Peruzzini, Maurizio; Sinicropi, Adalgisa; Basosi, Riccardo; Fabrizi de Biani, Fabrizia; Taddei, Maurizio; Colonna, Daniele; Di Carlo, Aldo; Reginato, Gianna; Zani, Lorenzo

2014-11-21

41

Degradation of wastewaters containing organic dyes photocatalysed by zinc oxide: a review  

Microsoft Academic Search

Organic dyes are one of the largest groups of pollutants discharged into wastewaters from textile and other industrial processes. Owing to the potential toxicity of the dyes and their visibility in surface waters, removal and degradation of them have attracted considerable attention worldwide. A wide range of approaches have been developed, amongst which the heterogeneous photocatalysis involving zinc oxide (ZnO)

Sze-Mun Lam; Jin-Chung Sin; Ahmad Zuhairi Abdullah; Abdul Rahman Mohamed

2012-01-01

42

Efficient organic dye-sensitized solar cells: molecular engineering of donor-acceptor-acceptor cationic dyes.  

PubMed

Three metal-free donor-acceptor-acceptor sensitizers with ionized pyridine and a reference dye were synthesized, and a detailed investigation of the relationship between the dye structure and the photophysical and photoelectrochemical properties and the performance of dye-sensitized solar cells (DSSCs) is described. The ionization of pyridine results in a red shift of the absorption spectrum in comparison to that of the reference dye. This is mainly attributable to the ionization of pyridine increasing the electron-withdrawing ability of the total acceptor part. Incorporation of the strong electron-withdrawing units of pyridinium and cyano acrylic acid gives rise to optimized energy levels, resulting in a large response range of wavelengths. When attached to TiO2 film, the conduction band of TiO2 is negatively shifted to a different extent depending on the dye. This is attributed to the electron recombination rate between the TiO2 film and the electrolyte being efficiently suppressed by the introduction of long alkyl chains and thiophene units. DSSCs assembled using these dyes show efficiencies as high as 8.8?%. PMID:24039097

Cheng, Ming; Yang, Xichuan; Zhao, Jianghua; Chen, Cheng; Tan, Qin; Zhang, Fuguo; Sun, Licheng

2013-12-01

43

Solvent-enhanced dye diffusion in polymer thin films for color tuning of organic light-emitting diodes  

E-print Network

only one color. Ink-jet printing of polymer solution,4­7 or screen printing of the polymer8 have been-jet printing of a dye solution on a substrate previously coated with polymer,9 or photobleaching of a dye.10Solvent-enhanced dye diffusion in polymer thin films for color tuning of organic light

44

Synthesis and Characterization of Organic Dyes Containing Various Donors and Acceptors  

PubMed Central

New organic dyes comprising carbazole, iminodibenzyl, or phenothiazine moieties, respectively, as the electron donors, and cyanoacetic acid or acrylic acid moieties as the electron acceptors/anchoring groups were synthesized and characterized. The influence of heteroatoms on carbazole, iminodibenzyl and phenothiazine donors, and cyano-substitution on the acid acceptor is evidenced by spectral, electrochemical, photovoltaic experiments, and density functional theory calculations. The phenothiazine dyes show solar-energy-to-electricity conversion efficiency (?) of 3.465.53%, whereas carbazole and iminodibenzyl dyes show ? of 2.43% and 3.49%, respectively. PMID:20162019

Wu, Tzi-Yi; Tsao, Ming-Hsiu; Chen, Fu-Lin; Su, Shyh-Gang; Chang, Cheng-Wen; Wang, Hong-Paul; Lin, Yuan-Chung; Ou-Yang, Wen-Chung; Sun, I-Wen

2010-01-01

45

Voltage-sensitive dyes reveal a modular organization in monkey striate cortex  

Microsoft Academic Search

Voltage-sensitive dyes allow neuronal activity to be studied by non-invasive optical techniques. They provide an attractive means of investigating striate cortex, where important response properties are organized in two dimensions. In the present study, patterns of ocular dominance and orientation selectivity were obtained repeatedly from the same patch of cortex using the dye merocyanine oxazolone, together with current image-processing techniques.

Gary G. Blasdel; Guy Salama

1986-01-01

46

MICROREVIEW Improving the Properties of Organic Dyes by Molecular Encapsulation  

E-print Network

,[a] Christopher C. Forbes,[a] and Bradley D. Smith*[a] Keywords: Cyclodextrins / Rotaxanes / Dendrimers / Gels such as cyclodextrins, cucurbiturils, dendri- mers, and self-assembled gels. Another strategy is perma- 1.0 Introduction.0 Cyclodextrin-Encapsulated Dyes Cyclodextrin (CD) is a fascinating molecule for supra- molecular chemists

Smith, Bradley D.

47

Solubilization of two organic dyes by cationic ester-containing gemini surfactants.  

PubMed

Solubilization of two different types of organic dyes, Quinizarin with an anthraquinone structure and Sudan I with an azo structure, has been studied in aqueous solutions of a series of cationic gemini surfactants and of a conventional monomeric cationic surfactant, dodecyltrimethylammonium bromide (DTAB). Surfactant concentrations both above and below the critical micelle concentration were used. The concentration of solubilized dye at equilibrium was determined from the absorbance of the solution at ?(max) with the aid of a calibration curve. The solubilization power of the gemini surfactants was higher than that of DTAB and increased with increasing alkyl chain length. An increase in length of the spacer unit resulted in increased solubilization power while a hydroxyl group in the spacer did not have much effect. Ester bonds in the alkyl chains reduced the solubilization power with respect to both dyes. A comparison between the absorbance spectra of the dyes in micellar solution with spectra in a range of solvents of different polarity indicated that the dye is situated in a relatively polar environment. One may therefore assume that the dye is located just below the head group region of the micelle. Attractive ?-cation interactions may play a role for orienting the dye to the outer region of the micelle. PMID:22444485

Tehrani-Bagha, A R; Singh, R G; Holmberg, K

2012-06-15

48

21 CFR 73.100 - Cochineal extract; carmine.  

Code of Federal Regulations, 2011 CFR

...70.25 of this chapter. (2) The label of food products intended for human use, including butter, cheese, and ice cream, that contain cochineal extract or carmine shall specifically declare the presence of the color additive by listing its...

2011-04-01

49

21 CFR 73.100 - Cochineal extract; carmine.  

Code of Federal Regulations, 2013 CFR

...70.25 of this chapter. (2) The label of food products intended for human use, including butter, cheese, and ice cream, that contain cochineal extract or carmine shall specifically declare the presence of the color additive by listing its...

2013-04-01

50

21 CFR 73.100 - Cochineal extract; carmine.  

Code of Federal Regulations, 2014 CFR

...70.25 of this chapter. (2) The label of food products intended for human use, including butter, cheese, and ice cream, that contain cochineal extract or carmine shall specifically declare the presence of the color additive by listing its...

2014-04-01

51

21 CFR 73.100 - Cochineal extract; carmine.  

Code of Federal Regulations, 2012 CFR

...70.25 of this chapter. (2) The label of food products intended for human use, including butter, cheese, and ice cream, that contain cochineal extract or carmine shall specifically declare the presence of the color additive by listing its...

2012-04-01

52

Novel D-D-?-A organic dyes based on triphenylamine and indole-derivatives for high performance dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

Two novel D-D-?-A organic dyes (SD1 and SD2) based on triphenylamine and indole donors are designed and synthesized for dye-sensitized solar cells (DSSCs). For the first time, an SCN group is introduced into a metal-free organic dye SD2. The effects of the SCN group on the photophysical, electrochemical and photovoltaic properties are investigated. It is found that the introduction of SCN group to the SD2 molecule leads to a higher molar extinction coefficient and better photovoltaic performances compared with dye SD1. Under AM 1.5G irradiation (100mWcm-2), a maximum power conversion efficiency (?) of 6.74% is obtained for the SD2-based DSSCs, higher than that of SCN-free dyes SD1 (?=5.53%). These results have demonstrated that the corporation of SCN group into the organic dye will be an effective approach to develop high-performance metal-free organic dyes.

Liu, Xunshan; Cao, Zhencai; Huang, Hongli; Liu, Xuxu; Tan, Yingzi; Chen, Huajie; Pei, Yong; Tan, Songting

2014-02-01

53

A multifunctional 3D chiral porous ferroelectric metal-organic framework for sensing small organic molecules and dye uptake.  

PubMed

A flexible aromatic multicarboxylate ligand and Cd(II) ions assemble into a chiral multihelical porous metal-organic framework with second-order nonlinear optical and ferroelectric properties. The obtained guest-free form highly selectively senses small organic molecules and adsorbs large dye molecules. PMID:25236428

Cao, Li-Hui; Wei, Yong-Li; Ji, Can; Ma, Ming-Li; Zang, Shuang-Quan; Mak, Thomas C W

2014-11-01

54

Adsorption study of an industrial dye by an organic clay  

Microsoft Academic Search

In this study, the adsorption of an industrial dye Supranol Yellow 4GL onto Cetyltrimethylammonium-bentonite (CTAB-bentonite)\\u000a is investigated. The organobentonite is synthesised by exchanging cetyltrimethylammonium cations (CTAB) with inorganic ions\\u000a on the surface of bentonite. The adsorption of Supranol Yellow 4GL onto organobentonite is found to be maximum when the concentration\\u000a of CTAB exchanged is 100% according to the cation exchange

A. Khenifi; Z. Bouberka; F. Sekrane; M. Kameche; Z. Derriche

2007-01-01

55

Comparative Studies on Rigid ? Linker-Based Organic Dyes: Structure-Property Relationships and Photovoltaic Performance.  

PubMed

A series of six structurally correlated donor-? bridge-acceptor organic dyes were designed, synthesized, and applied as sensitizers in dye-sensitized solar cells. Using the most widely studied donor (triarylamine) and cyclopenta[1,2-b:5,4-b']dithiophene or cyclopenta[1,2-b:5,4-b']dithiophene[2',1':4,5]thieno[2,3-d]thiophene as ? spacers, their structure-property relationships were investigated in depth by photophysical techniques and theoretical calculations. It was found that the photovoltaic performance of these dyes largely depends on their electronic structures, which requires synergistic interaction between donors and acceptors. Increasing the electron richness of the donor or the elongation of ?-conjugated bridges does not necessarily lead to higher performance. Rather, it is essential to rationally design the dyes by balancing their light-harvesting capability with achieving suitable energy levels to guarantee unimpeded charge separation and transport. PMID:25319943

Li, Hairong; Koh, Teck Ming; Hao, Yan; Zhou, Feng; Abe, Yuichiro; Su, Haibin; Hagfeldt, Anders; Grimsdale, Andrew C

2014-12-01

56

Organic heterojunctions of layered perylene and phthalocyanine dyes: characterization with UV-photoelectron spectroscopy and luminescence quenching  

Microsoft Academic Search

We present here the characterization of organic\\/organic' heterojunctions created from either of two perylene dyes, perylenetetracarboxylicdianhydride (PTCDA) or the bisimide derivative perylenetetracarboxylicdianhydride-N,N'-bis (butyl)imide (C4-PTCDI), and two chloro-metallated donor phthalocyanines (ClAlPc or ClInPc). The perylene dyes were selected to create thin films with the core of the perylene dye parallel to the substrate plane (PTCDA) or nearly vertical to the substrate

Dana M. Alloway; Neal R. Armstrong

2009-01-01

57

Organic dyes containing carbazole as donor and ?-linker: optical, electrochemical, and photovoltaic properties.  

PubMed

A series of new metal free organic dyes containing carbazole as donor and ?-linker have been synthesized and characterized as effective sensitizers for dye sensitized solar cells (DSSCs). The carbazole functionalized at C-2 and C-7 served as electron-rich bridge. The donor property of the carbazole is substantially enhanced on introduction of tert-butyl groups at C-3 and C-6 positions and the oxidation propensity of the dyes increased on insertion of thiophene unit in the conjugation pathway. These structural modifications fine-tuned the optical and electrochemical properties of the dyes. Additionally, the presence of tert-butyl groups on the carbazole nucleus minimized the intermolecular interactions which benefited the performance of DSSCs. The dyes served as efficient sensitizers in DSSCs owing to their promising optical and electrochemical properties. The efficiency of DSSCs utilizing these dyes as sensitizers ranged from 4.22 to 6.04%. The tert-butyl groups were found to suppress the recombination of injected electrons which contributed to the increment in the photocurrent generation (JSC) and open circuit voltage (VOC). A dye with carbazole donor functionalized with tert-butyl groups and the conjugation bridge composed of 2,7-disubstituted carbazole and thiophene fragments exhibited higher VOC value. However, the best device efficiency was observed for a dye with unsubstituted carbazole donor and the ?-linker featuring carbazole and bithiophene units due to the high photocurrent generation arising from the facile injection of photogenerated electrons into the conduction band of titanium dioxide (TiO2) facilitated by the low-lying LUMO. PMID:24456063

Venkateswararao, A; Thomas, K R Justin; Lee, Chuan-Pei; Li, Chun-Ting; Ho, Kuo-Chuan

2014-02-26

58

Electronic structure measurements of metal-organic solar cell dyes using x-ray absorption spectroscopy  

NASA Astrophysics Data System (ADS)

The focus of this thesis is twofold: to report the results of X-ray absorption studies of metal-organic dye molecules for dye-sensitized solar cells and to provide a basic training manual on X-ray absorption spectroscopy techniques and data analysis. The purpose of our research on solar cell dyes is to work toward an understanding of the factors influencing the electronic structure of the dye: the choice of the metal, its oxidation state, ligands, and cage structure. First we study the effect of replacing Ru in several common dye structures by Fe. First-principles calculations and X-ray absorption spectroscopy at the C 1s and N 1s edges are combined to investigate transition metal dyes in octahedral and square planar N cages. Octahedral molecules are found to have a downward shift in the N 1s-to-pi* transition energy and an upward shift in C 1s-to-pi* transition energy when Ru is replaced by Fe, explained by an extra transfer of negative charge from Fe to the N ligands compared to Ru. For the square planar molecules, the behavior is more complex because of the influence of axial ligands and oxidation state. Next the crystal field parameters for a series of phthalocyanine and porphyrins dyes are systematically determined using density functional calculations and atomic multiplet calculations with polarization-dependent X-ray absorption spectra. The polarization dependence of the spectra provides information on orbital symmetries which ensures the determination of the crystal field parameters is unique. A uniform downward scaling of the calculated crystal field parameters by 5-30% is found to be necessary to best fit the spectra. This work is a part of the ongoing effort to design and test new solar cell dyes. Replacing the rare metal Ru with abundant metals like Fe would be a significant advance for dye-sensitized solar cells. Understanding the effects of changing the metal centers in these dyes in terms of optical absorption, charge transfer, and electronic structure enables the systematic design of new dyes using less expensive materials.

Johnson, Phillip S.

59

Polylysine crosslinked AIE dye based fluorescent organic nanoparticles for biological imaging applications.  

PubMed

Fluorescent organic nanoparticles based on aggregation induced emission dyes are fabricated through a ring-opening reaction using polylysine as the linker. The fluorescent organic nanoparticles obtained are characterized by a series of techniques including UV-vis absorption spectroscopy, fluorescence spectroscopy, Fourier Transform infrared spectroscopy, and transmission electron microscopy. A biocompatibility evaluation and the cell uptake behavior of the fluorescent organic nanoparticles are further investigated to evaluate their potential biomedical applications. It is demonstrated that these fluorescent organic nanoparticles can be obtained at room temperature in an air atmosphere without the need for catalyst or initiator. Furthermore, these crosslinked aggregation induced emission dye based fluorescent organic nanoparticles show uniform morphology, strong red fluorescence, high water dispersability, and excellent biocompatibility, making them promising candidates for various biomedical applications. PMID:24854875

Liu, Meiying; Zhang, Xiqi; Yang, Bin; Liu, Liangji; Deng, Fengjie; Zhang, Xiaoyong; Wei, Yen

2014-09-01

60

Optical studies of glasses embedded with inorganic ions and organic dyes  

NASA Astrophysics Data System (ADS)

We performed optical studies of organic dye doped glasses and rare earth ion doped glasses. We doped several organic dyes in boric acid, sucrose, and polycarbonate hosts and detected phase conjugate signals from all these samples. Sucrose samples are hygroscopic and hence are useful for characterizing dyes only. Boric acid samples were damaged even at moderate laser powers. On the other hand polycarbonate samples could withstand high input powers and hence will be useful in device applications. Styryl 7 doped boric acid sample exhibited several interesting nonlinear optical phenomena and was also found to be useful for long-term/permanent information storage due to photochemical effects undergone by the excited molecules. PC signals in Pyridine 1 dye doped samples exhibited oscillations (period-hour) which was found to be due to thermal effects/large Stokes shift in the emission. DCM and RI 10 doped boric acid samples are found to be chemically stable even after three years. We measured third order susceptibilities of DCF, DCM, RIIO, AY, and R6G doped samples. We experimentally demonstrated that excited state absorption alters the transmission/saturation characteristics of the dyes in condensed media. These results have been published in three journal papers.

Reddy, B. R.

1993-07-01

61

Magnetic fluid modified peanut husks as an adsorbent for organic dyes removal  

NASA Astrophysics Data System (ADS)

Magnetically responsive nanocomposite materials, prepared by modification of diamagnetic materials by magnetic fluids (ferrofluids), have already found many important applications in various areas of biosciences, medicine, biotechnology, environmental technology etc. Ferrofluid modified biological waste (peanut husks) has been successfully used for the separation and removal of water soluble organic dyes and thus this low cost adsorbent could be potentially used for waste water treatment.

Safarik, Ivo; Safarikova, Mirka

62

INDUSTRIAL PROCESS PROFILES FOR ENVIRONMENTAL USE: CHAPTER 7. ORGANIC DYES AND PIGMENTS INDUSTRY  

EPA Science Inventory

The catalog of Industrial Process Profiles for Environmental Use was developed as an aid in defining the environmental impacts of industrial activity in the United States. Entries for each industry are in consistent format and form separate chapters of the study. The organic dyes...

63

New D-A-?-A organic sensitizers for efficient dye-sensitized solar cells.  

PubMed

Four novel metal-free D-A-?-A organic sensitizers () based on N-annulated perylene (NP) derivatives as efficient electron donors for dye-sensitized solar cells (DSSCs) are designed. Among them, featuring bulky 4-methoxyphenyl as the additional electron-donating substituents on the NP unit shows a power conversion efficiency as high as 8.30%. PMID:25633152

Li, Xiangguang; Zheng, Zhiwei; Jiang, Wei; Wu, Wenjun; Wang, Zhaohui; Tian, He

2015-02-12

64

Influence of excitation conditions on laser action in organic dye solutions  

Microsoft Academic Search

The relationship between the laser action in organic dye solutions with an output energy of ~ 102 J and the pump source characteristics is discussed. It is shown that the specified conditions are satisfied best by a cavity electric-discharge pump source operating under a near-critical damped oscillatory regime. The most effective method for attaining this regime is a reduction in

B. A. Barikhin; B. S. Makaev; L. V. Sukhanov; A. I. Pavlovskii

1976-01-01

65

Photocatalytic Destruction of an Organic Dye Using TiO2 and Solar Energy.  

ERIC Educational Resources Information Center

Describes a general chemistry experiment that is carried out in sunlight to illustrate the ability of TiO2 to act as a photocatalyst by mineralizing an organic dye into carbon dioxide. Details about the construction of the reactor system used to perform this experiment are included. (DDR)

Giglio, Kimberly D.; And Others

1995-01-01

66

Organization of butadienyl dyes containing benzodithiacrown-ether or dimethoxybenzene in monolayers at the air/aqueous salt solution interface.  

PubMed

Two amphiphilic butadienyl dyes 1 and 2 form stable monolayers at the air/water interface in the presence of various salts. Dye 1 consists of the basic amphiphilic butadienyl chromophore. In dye 2, the dimethoxybenzene part of dye 1 is substituted by benzodithia-15-crown-5. The monolayers have been characterized by surface pressure-area and surface potential-area isotherms as well as Brewster angle microscopy and reflection spectroscopy. In contrast to dye 1, dye 2 interacts specifically with Hg(2+) and Ag(+) cations forming complexes. No complex formation was observed with alkali and earth alkali metal ions. The nature of the anion (Cl(-) or ClO(4)(-)) influences the monolayer behaviour of both dyes. At the air/water interface, besides monomers of the dyes, two types of associates are coexisting in the pure dye monolayers on aqueous salt solutions, attributed to dimers and aggregates, respectively. Their equilibria depend on the nature of both cations and anions in the subphase, as in the case of dye 2, or only anions, as in the case of dye 1. The dimers may be organized as head-to-tail dimers with the intermolecular distances 0.38 and 0.45nm for dye 1 and dye 2, respectively. According to the extended dipole model, we propose formation of aggregates in which the chromophores are parallel to each other with the same intermolecular distances as in the dimers, and the centers of their transition moments shifted by 0.95nm (dye 1) and 1.2nm (dye 2). PMID:19720508

Sergeeva, T I; Gromov, S P; Zaitsev, S Yu; Mbius, D

2009-12-01

67

Carbazole-dendrimer-based donor-?-acceptor type organic dyes for dye-sensitized solar cells: effect of the size of the carbazole dendritic donor.  

PubMed

A series of novel D-?-A type organic dyes, namely, GnTA (n = 1-4), containing carbazole dendrons up to fourth generation as a donor, bithiophene as ?-linkage, and cyanoacrylic acid as acceptor were synthesized and characterized for applications in dye-sensitized solar cells (DSSCs). The photophysical, thermal, electrochemical, and photovoltaic properties of the new dyes as dye sensitizers were investigated, and the effects of the carbazole dendritic donors on these properties were evaluated. Results demonstrated that increasing the size or generation of the carbazole dendritic donor of the dye molecules enhances their total light absorption abilities and unluckily reduces the amount of dye uptake per unit TiO2 area because of their high molecular volumes. The latter was found to have a strong effect on the power conversion efficiency of DSSCs. Importantly, electrochemical impedance spectroscopy (EIS) revealed that the size or generation of the donor had a significant influence on a charge-transfer resistance for electron recombination at the TiO2/electrolyte interface, causing a difference in open circuit voltage (Voc) of the solar cells. Among them, dye G1TA containing first generation dendron as a donor (having lowest molecular volume) exhibited the highest power conversion efficiency of 5.16% (Jsc = 9.89 mA cm(-2), Voc = 0.72 V, ff = 0.73) under simulated AM 1.5 irradiation (100 mW cm(-2)). PMID:24878449

Thongkasee, Pongsathorn; Thangthong, Amonrat; Janthasing, Nittaya; Sudyoadsuk, Taweesak; Namuangruk, Supawadee; Keawin, Tinnagon; Jungsuttiwong, Siriporn; Promarak, Vinich

2014-06-11

68

Degradation of cyanoacrylic acid-based organic sensitizers in dye-sensitized solar cells.  

PubMed

Organic dyes have become widely used in dye-sensitized solar cells (DSSCs) because of their good performance, flexible structural modifications, and low costs. To increase the photostability of organic dye-based DSSCs, we conducted a full study on the degradation mechanism of cyanoacrylic acid-based organic sensitizers in DSSCs. The results showed that with the synergy between water and UV light, the sensitizer could desorb from the TiO2 surface and the cyanoacrylic acid unit of the sensitizer was transformed into the aldehyde group. It was also observed that the water content had a great effect on the degradation process. Our experiments conducted using (18) O-labeled water demonstrated that the oxygen atom of the aldehyde group identified in the degraded dye came from the solvent water in the DSSCs. Therefore, controlling the water content during DSSC fabrication, good sealing of cells, and filtering the UV light are crucial to produce DSSCs that are more durable and robust. PMID:23775933

Chen, Cheng; Yang, Xichuan; Cheng, Ming; Zhang, Fuguo; Sun, Licheng

2013-07-01

69

Intermolecular interactions between a Ru complex and organic dyes in cosensitized solar cells: a computational study.  

PubMed

Intermolecular interactions in cyclometalated Ru complex dye (FT89) dimers, carbazole organic dye (MK-45 and MK-111) dimers, FT89-MK-45 complexes, and FT89-MK-111 complexes were investigated using density functional theory (DFT) and time-dependent DFT (TD-DFT) to elucidate the improvement mechanism of dye-sensitized solar cell (DSSC) performance due to cosensitization with FT89 and MK dyes. All of the dimers and complexes form intermolecular cyclic hydrogen bonds via the carboxyl groups. The FT89 dimer and complexes with the TiO2Na model system promote intermolecular interactions with I2via the NCS ligand of the FT89 monomer. The computational results verify that MK-111 behaves not only as a sensitizer but also inhibits FT89 aggregation by effectively serving as a coadsorbent similar to deoxycholic acid (DCA) in the dye solution, suppressing recombination of the injected electrons in TiO2 with I2, improving DSSC performance. PMID:24968132

Kusama, Hitoshi; Funaki, Takashi; Koumura, Nagatoshi; Sayama, Kazuhiro

2014-08-14

70

Suitability of dyeclay complexes for removal of non-ionic organic compounds from aqueous solutions  

Microsoft Academic Search

Aqueous sorption of phenol, atrazine and naphthalene was measured on complexes formed from Na-montmorillonite (Fischer bentonite) and the organic cationic dyes crystal violet and rhodamine-B. Sorption isotherms were found to be non-linear. This agrees well with the rigid nature of the dyeclay organic coverage, which provides a finite surface for adsorption. High values of organic carbon-normalized distribution coefficients reached 20,00025,000

Mikhail Borisover; Ellen R. Graber; Fernando Bercovich; Zev Gerstl

2001-01-01

71

A robust organic dye for dye sensitized solar cells based on iodine/iodide electrolytes combining high efficiency and outstanding stability.  

PubMed

Among the new photovoltaic technologies, the Dye-Sensitized Solar Cell (DSC) is becoming a realistic approach towards energy markets such as BIPV (Building Integrated PhotoVoltaics). In order to improve the performances of DSCs and to increase their commercial attractiveness, cheap, colourful, stable and highly efficient ruthenium-free dyes must be developed. Here we report the synthesis and complete characterization of a new purely organic sensitizer (RK1) that can be prepared and synthetically upscaled rapidly. Solar cells containing this orange dye show a power conversion efficiency of 10.2% under standard conditions (AM 1.5G, 1000?Wm(-2)) using iodine/iodide as the electrolyte redox shuttle in the electrolyte, which is among the few examples of DSC using an organic dyes and iodine/iodide red/ox pair to overcome the 10% efficiency barrier. We demonstrate that the combination of this dye with an ionic liquid electrolyte allows the fabrication of solar cells that show power conversion efficiencies of up to 7.36% that are highly stable with no measurable degradation of initial performances after 2200?h of light soaking at 65C under standard irradiation conditions. RK1 achieves one of the best output power conversion efficiencies for a solar cell based on the iodine/iodide electrolyte, combining high efficiency and outstanding stability. PMID:24504344

Joly, Damien; Pellej, Laia; Narbey, Stphanie; Oswald, Frdric; Chiron, Julien; Clifford, John N; Palomares, Emilio; Demadrille, Renaud

2014-01-01

72

A Robust Organic Dye for Dye Sensitized Solar Cells Based on Iodine/Iodide Electrolytes Combining High Efficiency and Outstanding Stability  

PubMed Central

Among the new photovoltaic technologies, the Dye-Sensitized Solar Cell (DSC) is becoming a realistic approach towards energy markets such as BIPV (Building Integrated PhotoVoltaics). In order to improve the performances of DSCs and to increase their commercial attractiveness, cheap, colourful, stable and highly efficient ruthenium-free dyes must be developed. Here we report the synthesis and complete characterization of a new purely organic sensitizer (RK1) that can be prepared and synthetically upscaled rapidly. Solar cells containing this orange dye show a power conversion efficiency of 10.2% under standard conditions (AM 1.5G, 1000?Wm?2) using iodine/iodide as the electrolyte redox shuttle in the electrolyte, which is among the few examples of DSC using an organic dyes and iodine/iodide red/ox pair to overcome the 10% efficiency barrier. We demonstrate that the combination of this dye with an ionic liquid electrolyte allows the fabrication of solar cells that show power conversion efficiencies of up to 7.36% that are highly stable with no measurable degradation of initial performances after 2200?h of light soaking at 65C under standard irradiation conditions. RK1 achieves one of the best output power conversion efficiencies for a solar cell based on the iodine/iodide electrolyte, combining high efficiency and outstanding stability. PMID:24504344

Joly, Damien; Pellej, Laia; Narbey, Stphanie; Oswald, Frdric; Chiron, Julien; Clifford, John N.; Palomares, Emilio; Demadrille, Renaud

2014-01-01

73

Corrosion inhibition of mild steel in acidic media by some organic dyes  

Microsoft Academic Search

The inhibitive capabilities of some organic dyes namely; safranine-o (SO), thymol blue (TB) and fluorescein-Na (F-Na) on the electrochemical corrosion of mild steel in sulphuric acid solution was rapidly assessed using the gasometric technique. The results indicate that all of the studied compounds act as inhibitors in the acidic corrodent. Inhibition efficiency increased with concentration for SO and TB but

E. E. Ebenso; E. E. Oguzie

2005-01-01

74

Correction: Sacrificial template-directed synthesis of mesoporous manganese oxide architectures with superior performance for organic dye adsorption  

NASA Astrophysics Data System (ADS)

Correction for `Sacrificial template-directed synthesis of mesoporous manganese oxide architectures with superior performance for organic dye adsorption' by Lunhong Ai et al., Nanoscale, 2012, 4, 5401-5408.

Ai, Lunhong; Yue, Haitao; Jiang, Jing

2014-10-01

75

Organic heterojunctions of layered perylene and phthalocyanine dyes: characterization with UV-photoelectron spectroscopy andluminescence quenching  

Microsoft Academic Search

We present here the characterization of organic\\/organic? heterojunctions created from either of two perylene dyes, perylenetetracarboxylicdianhydride\\u000a (PTCDA) or the bisimide derivative perylenetetracarboxylicdianhydride-N,N?-bis (butyl)imide (C4-PTCDI), and two chloro-metallated\\u000a donor phthalocyanines (ClAlPc or ClInPc). The perylene dyes were selected to create thin films with the core of the perylene\\u000a dye parallel to the substrate plane (PTCDA) or nearly vertical to the substrate

Dana M. Alloway; Neal R. Armstrong

2009-01-01

76

Tailor-made hole-conducting coadsorbents for highly efficient organic dye-sensitized solar cells.  

PubMed

The Y-shaped, low molecular mass, hole-conductor (HC), acidic coadsorbents 4-{3,7-bis[4-(2-ethylhexyloxy)phenyl]-10H-phenothiazin-10-yl}benzoic acid (PTZ1) and 4-{3,7-bis[4-(2-ethylhexyloxy)phenyl]-10H-phenothiazin-10-yl}biphenyl-4-carboxylic acid (PTZ2) were developed. Owing to their tuned and negative-shifted HOMO levels (vs. NHE), they were used as HC coadsorbents in dye-sensitized solar cells (DSSCs) to improve cell performance through desired cascade-type hole-transfer processes. Their detailed functions as HC coadsorbents in DSSCs were investigated to obtain evidence for the desired cascade-type hole-transfer processes. They have multiple functions, such as preventing ?-? stacking of dye molecules, harvesting light of shorter wavelengths, and faster dye regeneration. By using PTZ2 as the tailor-made HC coadsorbent on the TiO2 surface with the organic dye NKX2677, an extremely high conversion efficiency of 8.95?% was achieved under 100?mW?cm(-2) AM 1.5G simulated light (short-circuit current JSC =16.56?mA?cm(-2) , open-circuit voltage VOC =740?mV, and fill factor of 73?%). Moreover, JSC was increased by 13?%, VOC by 27?% and power-conversion efficiency by 49?% in comparison to an NKX2677-based DSSC without an HC coadsorbent. This is due to the HC coadsorbent having a HOMO energy level well matched to that of the NKX-2677 dye to induce the desired cascade-type hole-transfer processes, which are associated with a slower charge recombination, fast dye regeneration, effective screening of liquid electrolytes, and an induced negative shift of the quasi-Fermi level of the electrode. Thus, this new class of Y-shaped, low molecular weight, organic, HC coadsorbents based on phenothiazine carboxylic acid derivatives hold promise for highly efficient organic DSSCs. PMID:24115151

Choi, In Taek; Ju, Myung Jong; Song, Sang Hyun; Kim, Sang Gyun; Cho, Dae Won; Im, Chan; Kim, Hwan Kyu

2013-11-11

77

Third-order nonlinear optical response of indigo carmine under 633 nm excitation for nonlinear optical applications  

NASA Astrophysics Data System (ADS)

We report thermally induced third-order nonlinearity and optical limiting behaviour of Indigo Carmine dye. z-Scan technique was used to determine the sign and magnitude of absorptive and refractive nonlinearities. Continuous wave (CW) He-Ne laser operating at 633 nm was used as source of excitation. In open aperture z-scan experiments, samples exhibited reverse saturable absorption (RSA) process. For closed aperture z-scan experiments, samples revealed self-defocusing property. The presence of donor and acceptor groups in the structure increases the conjugation length and in turn increases the optical nonlinearity. Induced self-diffraction rings pattern was recorded for the samples and it is attributed to refractive index change and thermal lensing. Also, optical limiting and clamping studies were carried out for various input power. Optical clamping of about ~1 mW was observed. This endorses that the dye under investigation is a positive candidate for opto-electronic and photonic applications.

Pramodini, S.; Poornesh, P.

2014-11-01

78

Tailoring of Energy Levels in D-?-A Organic Dyes via Fluorination of Acceptor Units for Efficient Dye-Sensitized Solar Cells.  

PubMed

A molecular design is presented for tailoring the energy levels in D-?-A organic dyes through fluorination of their acceptor units, which is aimed at achieving efficient dye-sensitized solar cells (DSSCs). This is achieved by exploiting the chemical structure of common D-?-A organic dyes and incorporating one or two fluorine atoms at the ortho-positions of the cyanoacetic acid as additional acceptor units. As the number of incorporated fluorine atoms increases, the LUMO energy level of the organic dye is gradually lowered due to the electron-withdrawing effect of fluorine, which ultimately results in a gradual reduction of the HOMO-LUMO energy gap and an improvement in the spectral response. Systematic investigation of the effects of incorporating fluorine on the photovoltaic properties of DSSCs reveals an upshift in the conduction-band potential of the TiO2 electrode during impedance analysis; however, the incorporation of fluorine also results in an increased electron recombination rate, leading to a decrease in the open-circuit voltage (Voc). Despite this limitation, the conversion efficiency is gradually enhanced as the number of incorporated fluorine atoms is increased, which is attributed to the highly improved spectral response and photocurrent. PMID:25591722

Lee, Min-Woo; Kim, Jae-Yup; Son, Hae Jung; Kim, Jin Young; Kim, BongSoo; Kim, Honggon; Lee, Doh-Kwon; Kim, Kyungkon; Lee, Duck-Hyung; Ko, Min Jae

2015-01-01

79

Tailoring of Energy Levels in D-?-A Organic Dyes via Fluorination of Acceptor Units for Efficient Dye-Sensitized Solar Cells  

PubMed Central

A molecular design is presented for tailoring the energy levels in D-?-A organic dyes through fluorination of their acceptor units, which is aimed at achieving efficient dye-sensitized solar cells (DSSCs). This is achieved by exploiting the chemical structure of common D-?-A organic dyes and incorporating one or two fluorine atoms at the ortho-positions of the cyanoacetic acid as additional acceptor units. As the number of incorporated fluorine atoms increases, the LUMO energy level of the organic dye is gradually lowered due to the electron-withdrawing effect of fluorine, which ultimately results in a gradual reduction of the HOMO-LUMO energy gap and an improvement in the spectral response. Systematic investigation of the effects of incorporating fluorine on the photovoltaic properties of DSSCs reveals an upshift in the conduction-band potential of the TiO2 electrode during impedance analysis; however, the incorporation of fluorine also results in an increased electron recombination rate, leading to a decrease in the open-circuit voltage (Voc). Despite this limitation, the conversion efficiency is gradually enhanced as the number of incorporated fluorine atoms is increased, which is attributed to the highly improved spectral response and photocurrent. PMID:25591722

Lee, Min-Woo; Kim, Jae-Yup; Son, Hae Jung; Kim, Jin Young; Kim, BongSoo; Kim, Honggon; Lee, Doh-Kwon; Kim, Kyungkon; Lee, Duck-Hyung; Ko, Min Jae

2015-01-01

80

Tailoring of Energy Levels in D-?-A Organic Dyes via Fluorination of Acceptor Units for Efficient Dye-Sensitized Solar Cells  

NASA Astrophysics Data System (ADS)

A molecular design is presented for tailoring the energy levels in D-?-A organic dyes through fluorination of their acceptor units, which is aimed at achieving efficient dye-sensitized solar cells (DSSCs). This is achieved by exploiting the chemical structure of common D-?-A organic dyes and incorporating one or two fluorine atoms at the ortho-positions of the cyanoacetic acid as additional acceptor units. As the number of incorporated fluorine atoms increases, the LUMO energy level of the organic dye is gradually lowered due to the electron-withdrawing effect of fluorine, which ultimately results in a gradual reduction of the HOMO-LUMO energy gap and an improvement in the spectral response. Systematic investigation of the effects of incorporating fluorine on the photovoltaic properties of DSSCs reveals an upshift in the conduction-band potential of the TiO2 electrode during impedance analysis; however, the incorporation of fluorine also results in an increased electron recombination rate, leading to a decrease in the open-circuit voltage (Voc). Despite this limitation, the conversion efficiency is gradually enhanced as the number of incorporated fluorine atoms is increased, which is attributed to the highly improved spectral response and photocurrent.

Lee, Min-Woo; Kim, Jae-Yup; Son, Hae Jung; Kim, Jin Young; Kim, Bongsoo; Kim, Honggon; Lee, Doh-Kwon; Kim, Kyungkon; Lee, Duck-Hyung; Ko, Min Jae

2015-01-01

81

Metal-organic frameworks at interfaces in dye-sensitized solar cells.  

PubMed

ZIF-8, a kind of widely studied metal-organic frameworks, was used for the interfacial modification of dye-sensitized solar cells by a facile post-treatment strategy for the first time, which solved the problem of severely decreased short-circuit photocurrent in previous report. After the surface treatment, the performance of cells was obviously improved. The conditions for the deposition of ZIF-8 were optimized. The best photovoltaic property was obtained when the growth time of ZIF-8 was 7?min and the TiO2 photoanode was post-treated for 2 times. Besides the energy barrier effect of ZIF-8 that improved the open-circuit photovoltage and electron lifetime, the dyes adsorbed tightly on TiO2 surface was found to be a key point for the efficient electron injection and improved performance. PMID:24989826

Li, Yafeng; Chen, Caiyun; Sun, Xun; Dou, Jie; Wei, Mingdeng

2014-09-01

82

Quantum dot and quantum dot-dye co-sensitized solar cells containing organic thiolate-disulfide redox electrolyte  

NASA Astrophysics Data System (ADS)

Quantum dot sensitized solar cells (QDSSCs) require special electrolytes, which are not always compatible with the requirements of dye sensitized solar cells. CdS and PbS quantum dot sensitized solar cells are able to show promising power conversion efficiencies in the presence of an organic thiolate/disulfide redox electrolyte. Also, an appreciable enhancement in performance is noticed when such devices are co-sensitized with a Ru-dye. The measured cell efficiencies of the CdS/dye and PbS/dye co-sensitized solar cells are 3.93% and 4.18%, respectively, which are higher than the sum of the corresponding individual QDSSCs and the dye sensitized solar cell (DSSCs). The enhancement seen with co-sensitization was investigated and explained by the fact that it suppressed back electron transfer processes in the cell, which was ascertained by electrochemical impedance spectroscopy (EIS) results.

Meng, Ke; Surolia, Praveen K.; Byrne, Owen; Thampi, K. Ravindranathan

2015-02-01

83

Enhanced anaerobic fermentation with azo dye as electron acceptor: simultaneous acceleration of organics decomposition and azo decolorization.  

PubMed

Accumulation of hydrogen during anaerobic processes usually results in low decomposition of volatile organic acids (VFAs). On the other hand, hydrogen is a good electron donor for dye reduction, which would help the acetogenic conversion in keeping low hydrogen concentration. The main objective of the study was to accelerate VFA composition through using azo dye as electron acceptor. The results indicated that the azo dye serving as an electron acceptor could avoid H2 accumulation and accelerate anaerobic digestion of VFAs. After adding the azo dye, propionate decreased from 2400.0 to 689.5mg/L and acetate production increased from 180.0 to 519.5mg/L. It meant that the conversion of propionate into acetate was enhanced. Fluorescence in situ hybridization analysis showed that the abundance of propionate-utilizing acetogens with the presence of azo dye was greater than that in a reference without azo dye. The experiments via using glucose as the substrate further demonstrated that the VFA decomposition and the chemical oxygen demand (COD) removal increased by 319.7mg/L and 23.3% respectively after adding the azo dye. Therefore, adding moderate azo dye might be a way to recover anaerobic system from deterioration due to the accumulation of H2 or VFAs. PMID:25288539

Li, Yang; Zhang, Yaobin; Quan, Xie; Zhang, Jingxin; Chen, Shuo; Afzal, Shahzad

2014-10-01

84

Synthesis of Organic Dye-Impregnated Silica Shell-Coated Iron Oxide Nanoparticles by a New Method  

NASA Astrophysics Data System (ADS)

A new method for preparing magnetic iron oxide nanoparticles coated by organic dye-doped silica shell was developed in this article. Iron oxide nanoparticles were first coated with dye-impregnated silica shell by the hydrolysis of hexadecyltrimethoxysilane (HTMOS) which produced a hydrophobic core for the entrapment of organic dye molecules. Then, the particles were coated with a hydrophilic shell by the hydrolysis of tetraethylorthosilicate (TEOS), which enabled water dispersal of the resulting nanoparticles. The final product was characterized by X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, photoluminescence spectroscopy, and vibration sample magnetometer. All the characterization results proved the final samples possessed magnetic and fluorescent properties simultaneously. And this new multifunctional nanomaterial possessed high photostability and minimal dye leakage.

Ren, Cuiling; Li, Jinhua; Liu, Qian; Ren, Juan; Chen, Xingguo; Hu, Zhide; Xue, Desheng

2008-12-01

85

DFT and TD-DFT study on structure and properties of organic dye sensitizer TA-St-CA  

Microsoft Academic Search

The geometry, electronic structure, polarizability and hyperpolarizability of organic dye sensitizer TA-St-CA, which contains a ?-conjugated oligo-phenylenevinylene unit with an electron donoracceptor moiety, was studied using density functional theory (DFT), and the electronic absorption spectrum was investigated via time-dependent DFT (TD-DFT) with several hybrid functionals. The calculated geometry indicates that the strong conjugated effects are formed in the dye. The

Cai-Rong Zhang; Zi-Jiang Liu; Yu-Hong Chen; Hong-Shan Chen; You-Zhi Wu; Wangjun Feng; Dao-Bin Wang

2010-01-01

86

A Research Module for the Organic Chemistry Laboratory: Multistep Synthesis of a Fluorous Dye Molecule.  

PubMed

A multi-session research-like module has been developed for use in the undergraduate organic teaching laboratory curriculum. Students are tasked with planning and executing the synthesis of a novel fluorous dye molecule and using it to explore a fluorous affinity chromatography separation technique, which is the first implementation of this technique in a teaching laboratory. Key elements of the project include gradually introducing students to the use of the chemical literature to facilitate their searching, as well as deliberate constraints designed to force them to think critically about reaction design and optimization in organic chemistry. The project also introduces students to some advanced laboratory practices such as Schlenk techniques, degassing of reaction mixtures, affinity chromatography, and microwave-assisted chemistry. This provides students a teaching laboratory experience that closely mirrors authentic synthetic organic chemistry practice in laboratories throughout the world. PMID:24501431

Slade, Michael C; Raker, Jeffrey R; Kobilka, Brandon; Pohl, Nicola L B

2014-01-14

87

Identification of natural dyes in archeological Coptic textiles by liquid chromatography with diode array detection.  

PubMed

Reversed-phase HPLC with diode-array UV-Vis spectrophotometric detection has been used for identification of natural dyes in extracts from wool and silk fibres from archeological textiles. The examined objects originate from 4th to 12th Century Egypt and belong to the collection of Early Christian Art of the National Museum in Warsaw. Extraction from fibres was carried out with HCl solution containing ethanol or with warm pyridine. As the main individual chemical components of natural dyes, anthraquinone, indigoid and flavonoid dyes including alizarin, purpurin, luteolin, apigenin, carminic acid, ellagic acid, gallic acid, laccaic acids A and B and indigotin were found. For pyridine extracts another mobile phase with an optimized gradient of organic modifier concentration was used. With such an eluent the appearance of double peaks for indigotin and indirubin was eliminated. For acidic extraction of dyes from fibres, ethanol was used. Due to its higher boiling point than methanol it evaporates slower from the extraction solution enabling a more efficient extraction of dyes. PMID:12650256

Orska-Gawry?, Jowita; Surowiec, Izabella; Kehl, Jerzy; Rejniak, Hanna; Urbaniak-Walczak, Katarzyna; Trojanowicz, Marek

2003-03-14

88

Theoretical investigation on structural and electronic properties of organic dye C258 on TiO?(101) surface in dye-sensitized solar cells.  

PubMed

The structural and electronic properties of an organic dye C258 before and after being adsorbed onto a TiO2(101) surface by two adsorption modes, monodentate (Mha) and bidentate bridging (BBH), have been investigated in detail. The combination of density functional tight-binding (DFTB), density functional theory (DFT), and time-dependent DFT (TDDFT) approaches have been employed. DFT calculations show that C258 has remarkable charge-transfer characteristics, which favors fast electron injection from the excited dye to the conduction band of TiO2. A detailed analysis of the adsorbate contributions of the dye molecule to band states of TiO2 shows a strong coupling of the adsorbate orbitals with the substrate orbitals. Significant electronic transfer characteristics across the interface reveal a direct electron injection mechanism arising from the electronic excitation of the anchoring group of C258 to the conduction bands of TiO2. The adsorption energy and the electron density distribution demonstrate that the BBH structure is more stable and has a stronger coupling with TiO2 than the Mha pattern, which is able to better promote the electron injection to increase the efficiency of dye-sensitized solar cells (DSSCs). PMID:25201320

Sun, Ping-Ping; Li, Quan-Song; Yang, Li-Na; Sun, Zhu-Zhu; Li, Ze-Sheng

2014-10-21

89

Sol-gel-derived silica films with tailored microstructures for applications requiring organic dyes  

SciTech Connect

A three-step sol-gel process was developed to prepare organic dye-doped thin films with tailored porosity for applications in chemical sensing and optoelectronics. Varying the acid- and base-catalyzed hydrolysis steps of sols prepared from tetraethoxysilane with identical final H{sub 2}O/Si ratios, dilution factors and pH resulted in considerably different distributions of the silicate polymers in the sol (determined by {sup 29}Si NMR) and considerably different structures for the polymer clusters (determined by SAXS). During film formation these kinetic effects cause differences in the packing and collapse of the silicate network, leading to thin films with different refractive indices and volume fraction porosities. Under conditions where small pore-plugging species were avoided, the porosities of as-deposited films could be varied by aging the sol prior to film deposition. This strategy, which relies on the growth and aggregation of fractal polymeric clusters, is compatible with the low temperature and near neutral pH requirements of organic dyes.

Logan, M.N. [Sandia National Labs., Albuquerque, NM (United States); Prabakar, S. [Univ. of New Mexico, Albuquerque, NM (United States); Brinker, C.J. [Sandia National Labs., Albuquerque, NM (United States)]|[Univ. of New Mexico, Albuquerque, NM (United States)

1994-09-01

90

Hierarchical assembly of metal nanoparticles, quantum dots and organic dyes using DNA origami scaffolds  

NASA Astrophysics Data System (ADS)

The self-assembly of nanoscale elements into three-dimensional structures with precise shapes and sizes is important in fields such as nanophotonics, metamaterials and biotechnology. Short molecular linkers have previously been used to create assemblies of nanoparticles, but the approach is limited to small interparticle distances, typically less than 10 nm. Alternatively, DNA origami can precisely organize nanoscale objects over much larger length scales. Here we show that rigid DNA origami scaffolds can be used to assemble metal nanoparticles, quantum dots and organic dyes into hierarchical nanoclusters that have a planet-satellite-type structure. The nanoclusters have a tunable stoichiometry, defined distances of 5-200 nm between components, and controllable overall sizes of up to 500 nm. We also show that the nanoscale components can be positioned along the radial DNA spacers of the nanostructures, which allows short- and long-range interactions between nanoparticles and dyes to be studied in solution. The approach could, in the future, be used to construct efficient energy funnels, complex plasmonic architectures, and porous, nanoengineered scaffolds for catalysis.

Schreiber, Robert; Do, Jaekwon; Roller, Eva-Maria; Zhang, Tao; Schller, Verena J.; Nickels, Philipp C.; Feldmann, Jochen; Liedl, Tim

2014-01-01

91

Nanoscale insight into the exfoliation mechanism of graphene with organic dyes: effect of charge, dipole and molecular structure  

NASA Astrophysics Data System (ADS)

We study the mechanism of surface adsorption of organic dyes on graphene, and successive exfoliation in water of these dye-functionalized graphene sheets. A systematic, comparative study is performed on pyrenes functionalized with an increasing number of sulfonic groups. By combining experimental and modeling investigations, we find an unambiguous correlation between the graphene-dye interaction energy, the molecular structure and the amount of graphene flakes solubilized. The results obtained indicate that the molecular dipole is not important per se, but because it facilitates adsorption on graphene by a ``sliding'' mechanism of the molecule into the solvent layer, facilitating the lateral displacement of the water molecules collocated between the aromatic cores of the dye and graphene. While a large dipole and molecular asymmetry promote the adsorption of the molecule on graphene, the stability and pH response of the suspensions obtained depend on colloidal stabilization, with no significant influence of molecular charging and dipole.We study the mechanism of surface adsorption of organic dyes on graphene, and successive exfoliation in water of these dye-functionalized graphene sheets. A systematic, comparative study is performed on pyrenes functionalized with an increasing number of sulfonic groups. By combining experimental and modeling investigations, we find an unambiguous correlation between the graphene-dye interaction energy, the molecular structure and the amount of graphene flakes solubilized. The results obtained indicate that the molecular dipole is not important per se, but because it facilitates adsorption on graphene by a ``sliding'' mechanism of the molecule into the solvent layer, facilitating the lateral displacement of the water molecules collocated between the aromatic cores of the dye and graphene. While a large dipole and molecular asymmetry promote the adsorption of the molecule on graphene, the stability and pH response of the suspensions obtained depend on colloidal stabilization, with no significant influence of molecular charging and dipole. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr00258f

SchlierfThese Authors Contributed Equally To This Work., Andrea; Yang, Huafeng; Gebremedhn, Elias; Treossi, Emanuele; Ortolani, Luca; Chen, Liping; Minoia, Andrea; Morandi, Vittorio; Samor, Paolo; Casiraghi, Cinzia; Beljonne, David; Palermo, Vincenzo

2013-05-01

92

Encapsulation of large dye molecules in hierarchically superstructured metal-organic frameworks.  

PubMed

Microporous metal-organic frameworks (MOFs) represent a new family of microporous materials, offering potential applications in gas separation and storage, catalysis, and membranes. The engineering of hierarchical superstructured MOFs, i.e., fabricating mesopores in microporous frameworks during the crystallization stage is expected to serve a myriad of applications for molecular adsorption, drug delivery, and catalysis. However, MOFs with mesopores are rarely studied because of the lack of a simple, effective way to construct mesoscale cavities in the structures. Here, we report the use of a perturbation-assisted nanofusion technique to construct hierarchically superstructured MOFs. In particular, the mesopores in the MOF structure enabled the confinement of large dye species, resulting in fluorescent MOF materials, which can serve as a new type of ratiometric luminescent sensors for typical volatile organic compounds. PMID:25301034

Yue, Yanfeng; Binder, Andrew J; Song, Ruijing; Cui, Yuanjing; Chen, Jihua; Hensley, Dale K; Dai, Sheng

2014-12-28

93

Near infrared organic semiconducting materials for bulk heterojunction and dye-sensitized solar cells.  

PubMed

Dye sensitized solar cells (DSSCs) and bulk heterojunction (BHJ) solar cells have been the subject of intensive academic interest over the past two decades, and significant commercial effort has been directed towards this area with the vison of developing the next generation of low cost solar cells. Materials development has played a vital role in the dramatic improvement of both DSSC and BHJ solar cell performance in the recent years. Organic conjugated polymers and small molecules that absorb solar light in the visible and near infrared (NIR) regions represent a class of emering materials and show a great potential for the use of different optoelectronic devices such as DSSCs and BHJ solar cells. This account describes the emering class of near infrared (NIR) organic polymers and small molecules having donor and acceptors units, and explores their potential applications in the DSSCs and BHJ solar cells. PMID:24890453

Singh, Surya Prakash; Sharma, G D

2014-06-01

94

Investigation of electrodeposited cobalt sulphide counter electrodes and their application in next-generation dye sensitized solar cells featuring organic dyes and cobalt-based redox electrolytes  

NASA Astrophysics Data System (ADS)

Cobalt sulphide (CoS) films are potentiodynamically deposited on fluorine-doped tin oxide (FTO) coated glass substrates employing one, three and five sweep cycles (CoS-I, CoS-III and CoS-V respectively). Analysis of the CoS-III film by impedance spectroscopy reveals a lower charge transfer resistance (RCT) than that measured for Pt CE (0.75?cm-2 and 0.85?cm-2, respectively). The CoS films are used as counter electrodes (CE) in dye-sensitized solar cells (DSSCs) featuring the combination of a high absorption coefficient organic dye (C218) and the cobalt-based redox electrolyte [Co(bpy)3]2/3+. DSSCs fabricated with the CoS-III CE yield the highest short-circuit current density (JSC) of 12.84mAcm-2, open circuit voltage (VOC) of 805mV and overall power conversion efficiency (PCE) of 6.72% under AM 1.5G illumination (100mWcm-2). These values are comparable to the performance of an analogous cell fabricated with the Pt CE (PCE=6.94%). Owing to relative lower cost (due to the inherit earth abundance of Co) and non-toxicity, CoS can be considered as a promising alternative to the more expensive Pt as a CE material for next-generation DSSCs that utilize organic dyes and cobalt-based redox electrolytes.

Swami, Sanjay Kumar; Chaturvedi, Neha; Kumar, Anuj; Kapoor, Raman; Dutta, Viresh; Frey, Julien; Moehl, Thomas; Grtzel, Michael; Mathew, Simon; Nazeeruddin, Mohammad Khaja

2015-02-01

95

-encapsulated zero-valent iron nanoparticles for degradation of organic dyes  

NASA Astrophysics Data System (ADS)

A series of nanocomposites consisting of zero-valent iron nanoparticles (ZVI NPs) encapsulated in SiO2 microspheres were successfully synthesized through a successive two-step method, i.e., the wet chemical reduction by borohydride followed by a modified Stber method. The as-synthesized nanocomposites were characterized using X-ray diffraction, field emission scanning electron microscopy, vibrating sample magnetometer, and inductively coupled plasma-atomic emission spectrometer. The catalytic performance of SiO2-encapsulated ZVI nanocomposites for the degradation of organic dyes was investigated using methylene blue (MB) as the model dye in the presence of H2O2. The results showed that the degradation efficiency and apparent rate constant of the degradation reaction were significantly enhanced with increased ZVI NPs encapsulated in SiO2 microspheres, whereas the dosage of H2O2 remarkably promoted degradation rate without affecting degradation efficiency. The content-dependent magnetic property ensured the excellent magnetic separation of degradation products under an external magnet. This strategy for the synthesis of SiO2-encapsulated ZVI NPs nanocomposites was low cost and easy to scale-up for industrial production, thereby enabling promising applications in environmental remediation.

Mao, Zhou; Wu, Qingzhi; Wang, Min; Yang, Yushi; Long, Jia; Chen, Xiaohui

2014-09-01

96

Use of grape seed and its natural polyphenol extracts as a natural organic coagulant for removal of cationic dyes.  

PubMed

Natural organic coagulants (NOCs) such as chitosan and Moringa oleifera seeds have been extensively characterized for potential application in water treatment as an alternative to metal-based coagulants. However, the action of both chitosan and M. oleifera seeds is mainly restricted to anionic organic pollutants because of their cationic functional groups affording poor cationic pollutant coagulation by electrostatic repulsion. In this study, we employed ethanolic grape seed extract (GSE) and grape seed-derived polyphenols such as tannic acid and catechin in an effort to find novel NOCs showing stable anionic forms for removal of cationic organic pollutants. The target substances tested were malachite green (MG) and crystal violet (CV), both mutagenic cationic dyes. Polyphenol treatment induced fast decolorization followed by gradual floc formation concomitant with red or blue shifts in maximum absorbance wavelengths of the cationic dyes. Liquid chromatography analysis of flocs formed by polyphenols directly showed that initial supramolecular complexes attributed mainly to electrostatic attraction between polyphenol hydroxyphenyl groups and cationic dyes further progressed into stronger aggregates, leading to precipitation of dye-polyphenol complexes. Consistent with the results obtained using catechin and tannic acid, use of GSE also resulted in effective decolorization and coagulation of soluble MG and CV in aqueous solutions. Screening of several organic GSE components for NOC activity strongly suggested that natural polyphenols are the main organic ingredients causing MG and CV removal via gradual floc formation. The treatment by natural polyphenols and GSE decreased toxicity of MG- or CV-contaminated water. PMID:19786292

Jeon, Jong-Rok; Kim, Eun-Ju; Kim, Young-Mo; Murugesan, Kumarasamy; Kim, Jae-Hwan; Chang, Yoon-Seok

2009-11-01

97

Confinement of pyridinium hemicyanine dye within an anionic metal-organic framework for two-photon-pumped lasing  

PubMed Central

Two-photon-pumped dye lasers are very important because of their applications in wavelength up-conversion, optical data storage, biological imaging and photodynamic therapy. Such lasers are very difficult to realize in the solid state because of the aggregation-caused quenching. Here we demonstrate a new two-photon-pumped micro-laser by encapsulating the cationic pyridinium hemicyanine dye into an anionic metal-organic framework (MOF). The resultant MOF?dye composite exhibits significant two-photon fluorescence because of the large absorption cross-section and the encapsulation-enhanced luminescent efficiency of the dye. Furthermore, the well-faceted MOF crystal serves as a natural FabryPerot resonance cavity, leading to lasing around 640?nm when pumped with a 1064-nm pulse laser. This strategy not only combines the crystalline benefit of MOFs and luminescent behaviour of organic dyes but also creates a new synergistic two-photon-pumped lasing functionality, opening a new avenue for the future creation of solid-state photonic materials and devices. PMID:24173352

Yu, Jiancan; Cui, Yuanjing; Xu, Hui; Yang, Yu; Wang, Zhiyu; Chen, Banglin; Qian, Guodong

2013-01-01

98

Confinement of pyridinium hemicyanine dye within an anionic metal-organic framework for two-photon-pumped lasing  

NASA Astrophysics Data System (ADS)

Two-photon-pumped dye lasers are very important because of their applications in wavelength up-conversion, optical data storage, biological imaging and photodynamic therapy. Such lasers are very difficult to realize in the solid state because of the aggregation-caused quenching. Here we demonstrate a new two-photon-pumped micro-laser by encapsulating the cationic pyridinium hemicyanine dye into an anionic metal-organic framework (MOF). The resultant MOF?dye composite exhibits significant two-photon fluorescence because of the large absorption cross-section and the encapsulation-enhanced luminescent efficiency of the dye. Furthermore, the well-faceted MOF crystal serves as a natural Fabry-Perot resonance cavity, leading to lasing around 640?nm when pumped with a 1064-nm pulse laser. This strategy not only combines the crystalline benefit of MOFs and luminescent behaviour of organic dyes but also creates a new synergistic two-photon-pumped lasing functionality, opening a new avenue for the future creation of solid-state photonic materials and devices.

Yu, Jiancan; Cui, Yuanjing; Xu, Hui; Yang, Yu; Wang, Zhiyu; Chen, Banglin; Qian, Guodong

2013-10-01

99

Hierarchically porous silicon-carbon-nitrogen hybrid materials towards highly efficient and selective adsorption of organic dyes.  

PubMed

The hierarchically macro/micro-porous silicon-carbon-nitrogen (Si-C-N) hybrid material was presented with novel functionalities of totally selective and highly efficient adsorption for organic dyes. The hybrid material was conveniently generated by the pyrolysis of commercial polysilazane precursors using polydivinylbenzene microspheres as sacrificial templates. Owing to the Van der Waals force between sp-hybridized carbon domains and triphenyl structure of dyes, and electrostatic interaction between dyes and Si-C-N matrix, it exhibites high adsorption capacity and good regeneration and recycling ability for the dyes with triphenyl structure, such as methyl blue (MB), acid fuchsin (AF), basic fuchsin and malachite green. The adsorption process is determined by both surface adsorption and intraparticle diffusion. According to the Langmuir model, the adsorption capacity is 1327.7?mgg(-1) and 1084.5?mgg(-1) for MB and AF, respectively, which is much higher than that of many other adsorbents. On the contrary, the hybrid materials do not adsorb the dyes with azo benzene structures, such as methyl orange, methyl red and congro red. Thus, the hierarchically porous Si-C-N hybrid material from a facile and low cost polymer-derived strategy provides a new perspective and possesses a significant potential in the treatment of wastewater with complex organic pollutants. PMID:25604334

Meng, Lala; Zhang, Xiaofei; Tang, Yusheng; Su, Kehe; Kong, Jie

2015-01-01

100

Hierarchically porous siliconcarbonnitrogen hybrid materials towards highly efficient and selective adsorption of organic dyes  

NASA Astrophysics Data System (ADS)

The hierarchically macro/micro-porous silicon-carbon-nitrogen (Si-C-N) hybrid material was presented with novel functionalities of totally selective and highly efficient adsorption for organic dyes. The hybrid material was conveniently generated by the pyrolysis of commercial polysilazane precursors using polydivinylbenzene microspheres as sacrificial templates. Owing to the Van der Waals force between sp-hybridized carbon domains and triphenyl structure of dyes, and electrostatic interaction between dyes and Si-C-N matrix, it exhibites high adsorption capacity and good regeneration and recycling ability for the dyes with triphenyl structure, such as methyl blue (MB), acid fuchsin (AF), basic fuchsin and malachite green. The adsorption process is determined by both surface adsorption and intraparticle diffusion. According to the Langmuir model, the adsorption capacity is 1327.7 mg.g-1 and 1084.5 mg.g-1 for MB and AF, respectively, which is much higher than that of many other adsorbents. On the contrary, the hybrid materials do not adsorb the dyes with azo benzene structures, such as methyl orange, methyl red and congro red. Thus, the hierarchically porous Si-C-N hybrid material from a facile and low cost polymer-derived strategy provides a new perspective and possesses a significant potential in the treatment of wastewater with complex organic pollutants.

Meng, Lala; Zhang, Xiaofei; Tang, Yusheng; Su, Kehe; Kong, Jie

2015-01-01

101

Hierarchically porous siliconcarbonnitrogen hybrid materials towards highly efficient and selective adsorption of organic dyes  

PubMed Central

The hierarchically macro/micro-porous siliconcarbonnitrogen (SiCN) hybrid material was presented with novel functionalities of totally selective and highly efficient adsorption for organic dyes. The hybrid material was conveniently generated by the pyrolysis of commercial polysilazane precursors using polydivinylbenzene microspheres as sacrificial templates. Owing to the Van der Waals force between sp2-hybridized carbon domains and triphenyl structure of dyes, and electrostatic interaction between dyes and Si-C-N matrix, it exhibites high adsorption capacity and good regeneration and recycling ability for the dyes with triphenyl structure, such as methyl blue (MB), acid fuchsin (AF), basic fuchsin and malachite green. The adsorption process is determined by both surface adsorption and intraparticle diffusion. According to the Langmuir model, the adsorption capacity is 1327.7?mgg?1 and 1084.5?mgg?1 for MB and AF, respectively, which is much higher than that of many other adsorbents. On the contrary, the hybrid materials do not adsorb the dyes with azo benzene structures, such as methyl orange, methyl red and congro red. Thus, the hierarchically porous SiCN hybrid material from a facile and low cost polymer-derived strategy provides a new perspective and possesses a significant potential in the treatment of wastewater with complex organic pollutants. PMID:25604334

Meng, Lala; Zhang, Xiaofei; Tang, Yusheng; Su, Kehe; Kong, Jie

2015-01-01

102

Template-free hydrothermal derived cobalt oxide nanopowders: Synthesis, characterization, and removal of organic dyes  

SciTech Connect

Graphical abstract: XRD patterns of the products obtained by hydrothermal treatment at 160 C for 24 h, and at different [Co{sup 2+}]/[CO{sub 3}{sup 2?}] ratios: (a) 1:6, (b) 1:3, (c) 1:1.5, (d) 1:1, (e) 1:0.5. Highlights: ? Spinel cobalt oxide nanoparticles with different morphologies were prepared by hydrothermal approach. ? The optical characteristics of the as-prepared cobalt oxide revealed the presence of two band gaps. ? Adsorption of methylene blue dye on Co{sub 3}O{sub 4} was investigated and the percent uptake was found to be >99% in 24 h. -- Abstract: Pure spinel cobalt oxide nanoparticles were prepared through hydrothermal approach using different counter ions. First, the pure and uniform cobalt carbonate (with particle size of 21.829.8 nm) were prepared in high yield (94%) in an autoclave in absence unfriendly organic surfactants or solvents by adjusting different experimental parameters such as: pH, reaction time, temperature, counter ions, and (Co{sup 2+}:CO{sub 3}{sup 2?}) molar ratios. Thence, the spinel Co{sub 3}O{sub 4} (with mean particle size of 30.547.35 nm) was produced by thermal decomposition of cobalt carbonate in air at 500 C for 3 h. The products were characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FTIR), transmission electron microscope (TEM), scanning electron microscope (SEM), and thermal analysis (TA). Also, the optical characteristics of the as-prepared Co{sub 3}O{sub 4} nanoparticles revealed the presence of two band gaps (1.451.47, and 1.831.93 eV). Additionally, adsorption of methylene blue dye on Co{sub 3}O{sub 4} nanoparticles was investigated and the uptake% was found to be >99% in 24 h.

Nassar, Mostafa Y. [Chemistry Department, Faculty of Science, Benha University, Benha 13518 (Egypt)] [Chemistry Department, Faculty of Science, Benha University, Benha 13518 (Egypt); Ahmed, Ibrahim S., E-mail: isahmed2010@gmail.com [Chemistry Department, Faculty of Science, Benha University, Benha 13518 (Egypt)

2012-09-15

103

Photoinduced absorption measurement on a microchip equipped with organic dye-doped polymer waveguide  

NASA Astrophysics Data System (ADS)

We have fabricated a waveguide-type optical sensing microchip and succeeded in on-chip photoinduced absorption (PIA) spectroscopy. The PIA microchip was fabricated with a conventional photolithographic technique and consisted of plastic optical waveguides and microfluidic channels. Furthermore, a serially-cascaded polymer waveguide doped with organic dyes was integrated on this microchip, which was fabricated using a self-written waveguide process. This dye-doped waveguide was pumped by a UV light emitting diode (UV-LED) and used as a probe light source with a broad emission spectrum. At the same time, a solution of test material in the microfluidic channel was synchronously pumped by a UV-LED or UV laser diode. Since the transmission spectrum of the photo-excited test material could be measured, the PIA spectra were obtained easily. In this study, we have demonstrated the on-chip PIA measurements for two classes of test materials, rare-earth complex and chlorophyll molecules. In the measurement for the aqueous solution of Neodymium (III) acetate hydrate, PIA signals attributed to the 4f-4f transition was observed. Furthermore, by varying the modulation frequency of the pulsed optical pumping, lifetime analysis of the excited 4f states was achieved. In the measurements for the ethanol solutions of chlorophyll a and chlorophyll b, PIA signals were observed at the wavelength near the Q-band absorption peaks. These spectra were very similar to the well-known feature for the photosystem II protein complex observed in a conventional PIA system. From these results, it is expected that the onchip PIA measurement technique is applicable to the transient analyses for the material systems with photoexcited charge transfer.

Kawaguchi, T.; Nagai, K.; Yamashita, K.

2013-05-01

104

Organic heterojunctions of layered perylene and phthalocyanine dyes: characterization with UV-photoelectron spectroscopy and luminescence quenching  

NASA Astrophysics Data System (ADS)

We present here the characterization of organic/organic' heterojunctions created from either of two perylene dyes, perylenetetracarboxylicdianhydride (PTCDA) or the bisimide derivative perylenetetracarboxylicdianhydride-N,N'-bis (butyl)imide (C4-PTCDI), and two chloro-metallated donor phthalocyanines (ClAlPc or ClInPc). The perylene dyes were selected to create thin films with the core of the perylene dye parallel to the substrate plane (PTCDA) or nearly vertical to the substrate plane, with layer planes defined by the butyl substituents (C4-PTCDI). We compare the frontier orbital offsets revealed by UV-photoelectron spectroscopy, and quenching of luminescence of the perylene dyes, as a function of Pc coverage. The ionization potentials (IPs) of the Pc layers, the degree to which interface dipoles are formed at the Pc/perylene dye interface, and the degree of quenching of the perylene luminescence are affected by the structure of the Pc/perylene interface. Pc/PTCDA heterojunctions show significant interface dipoles and higher IPs for the first-deposited Pc layers compared to Pc/C4-PTCDI heterojunctions, which show negligible interface dipoles and lower overall IP values for initial Pc layers. Luminescence of the selectively excited perylene layers is quenched by the addition of even submonolayer coverages of Pc. This quenching process occurs as a result of both energy transfer (perylene to Pc) and charge transfer (Pc to perylene). Luminescence from monomeric and aggregated ClAlPc and ClInPc monolayers is seen on C4-PTCDI films, whereas only luminescence from the aggregated forms of these Pcs is seen on PTCDA films. These studies reveal aspects of organic heterojunction energetics which may have important implications for organic solar cell design.

Alloway, Dana M.; Armstrong, Neal R.

2009-04-01

105

Macrophages possess probenecid-inhibitable organic anion transporters that remove fluorescent dyes from the cytoplasmic matrix  

Microsoft Academic Search

We introduced several membrane- impermeant fluorescent dyes, including Lucifer Yellow, carboxyfluorescein, and fura-2, into the cytoplasmic matrix of J774 cells and thioglycollate-elicited mouse peritoneal macrophages by ATP permeabilization of the plasma membrane and observed the subsequent fate of these dyes. The dyes did not remain within the cytoplasmic matrix; instead they were sequestered within phase-lucent cytoplasmic vacuoles and released into

Thomas H. Steinberg; Alan S. Newman; Joel A. Swanson; Samuel C. Silverstein

1987-01-01

106

Photoconductivity of organic polymer films doped with porous silicon nanoparticles and ionic polymethine dyes  

SciTech Connect

Features of electrical conductivity and photoconductivity of polyvinylbutyral films containing porous silicon nanoparticles and similar films doped with cationic and anionic polymethine dyes are studied. Sensitization of the photoelectric effect by dyes with different ionicities in films is explained by the possible photogeneration of holes and electrons from dye molecules and the intrinsic bipolar conductivity of porous silicon nanoparticles. It is assumed that the electronic conductivity in porous silicon nanoparticles is higher in comparison with p-type conductivity.

Davidenko, N. A., E-mail: daviden@ukrpack.net; Skrichevsky, V. A. [Kiev National Taras Shevchenko University (Ukraine); Ishchenko, A. A. [National Academy of Sciences of Ukraine, Institute of Organic Chemistry (Ukraine); Karlash, A. Yu.; Mokrinskaya, E. V. [Kiev National Taras Shevchenko University (Ukraine)

2009-05-15

107

Removal of organic dyes using Cr-containing activated carbon prepared from leather waste.  

PubMed

In this work, hydrogen peroxide decomposition and oxidation of organics in aqueous medium were studied in the presence of activated carbon prepared from wet blue leather waste. The wet blue leather waste, after controlled pyrolysis under CO(2) flow, was transformed into chromium-containing activated carbons. The carbon with Cr showed high microporous surface area (up to 889 m(2)g(-1)). Moreover, the obtained carbon was impregnated with nanoparticles of chromium oxide from the wet blue leather. The chromium oxide was nanodispersed on the activated carbon, and the particle size increased with the activation time. It is proposed that these chromium species on the carbon can activate H(2)O(2) to generate HO radicals, which can lead to two competitive reactions, i.e. the hydrogen peroxide decomposition or the oxidation of organics in water. In fact, in this work we observed that activated carbon obtained from leather waste presented high removal of methylene blue dye combining the adsorption and oxidation processes. PMID:21752544

Oliveira, Luiz C A; Coura, Camila Van Zanten; Guimares, Iara R; Gonalves, Maraisa

2011-09-15

108

Stimulated resonance Raman scattering from organic dyes in a multiple-scattering medium as a potential method for determining their vibrational spectra  

NASA Astrophysics Data System (ADS)

A method is described for deriving Raman spectra of organic dyes from their random lasing spectra. The method was tested using Rhodamine 6G. The Raman spectrum obtained for this dye agrees well with the spectra measured by standard techniques but is more structured, which allows unresolved features to be detected. The spectrum provides more detailed information owing to the interference between the Raman scattered light and amplified spontaneous emission of the dye molecules within a photon mean free path. One advantage of the method is that the luminescence of the dye helps to observe Raman lines, which allows one to work in the Stokes region and facilitates the measurement procedure.

Yashchuk, V. P.; Tikhonov, E. A.; Bukatar', A. O.; Prigodiuk, O. A.; Smalyuk, A. P.

2011-10-01

109

Organic Dye Effects on DNAPL Entry Pressure in Water Saturated Porous Media  

SciTech Connect

One of three diazo dyes with the same fundamental structure have been used in most studies of DNAPL behavior in porous media to stain the NAPL: Sudan III, Sudan IV, or Oil-Red-O. The dyes are generally implicitly assumed to not influence DNAPL behavior. That assumption was tested using simple entry pressure experiments.

Iversen, G.M.

2001-10-02

110

An achievement of over 12 percent efficiency in an organic dye-sensitized solar cell.  

PubMed

Dye-sensitized solar cells fabricated by using a novel metal-free alkoxysilyl carbazole as a sensitizing dye and a Co(3+/2+)-complex redox electrolyte exhibited light-to-electric energy conversion efficiencies of over 12% with open-circuit photovoltages higher than 1 V by applying a hierarchical multi-capping treatment to the photoanode. PMID:24801395

Kakiage, Kenji; Aoyama, Yohei; Yano, Toru; Otsuka, Takahiro; Kyomen, Toru; Unno, Masafumi; Hanaya, Minoru

2014-06-18

111

Multifunctional organized mesoporous tin oxide films templated by graft copolymers for dye-sensitized solar cells.  

PubMed

The synthesis of organized mesoporous SnO2 films with high porosity, larger pores, and good interconnectivity, obtained by sol-gel templating with an amphiphilic graft copolymer, poly(vinyl chloride)-graft-poly(oxyethylene methacrylate), is reported. An improved performance of dye-sensitized solar cells (DSSCs) is demonstrated by the introduction of a 400 nm thick organized mesoporous SnO2 interfacial (om-SnO2 IF) layer between nanocrystalline TiO2 (nc-TiO2 ) and a fluorine-doped tin oxide substrate. To elucidate the improved efficiency, the structural, optical, and electrochemical properties of the devices were characterized by SEM, UV/Vis spectroscopy, noncontact 3D surface profilometry, intensity-modulated photocurrent/voltage spectroscopy, incident photon-to-electron conversion efficiency, and electrochemical impedance spectroscopy measurements. The energy-conversion efficiency of the solid polymerized ionic liquid based DSSC fabricated with the om-SnO2 IF/nc-TiO2 photoanode reached 5.9% at 100 mW cm(-2) ; this is higher than those of neat nc-TiO2 (3.5%) and organized mesoporous TiO2 interfacial/nc-TiO2 layer (5.4%) photoanodes. The improved efficiency is attributed to the antireflective property, cascadal energy band gap, good interconnectivity, and high electrical conductivity of the om-SnO2 IF layer, which results in enhanced light harvesting, increased electron transport, reduced charge recombination, and decreased interfacial/internal resistance. PMID:24678065

Park, Jung Tae; Ahn, Sung Hoon; Roh, Dong Kyu; Lee, Chang Soo; Kim, Jong Hak

2014-07-01

112

Novelmetal-organic photocatalysts: Synthesis, characterization and decomposition of organic dyes.  

PubMed

An efficient method for the photocatalytic degradation of methylene blue in an aqueous medium was developed using metal-organic complexes. Two novel complexes were synthesized using, Schiff base ligand, N'-[(E)-(4-ethylphenyl)methylidene]-4-hydroxybenzohydrazide (HL) and Ni(II) (Complex 1)/Co(II) (Complex 2) chloride respectively. These complexes were characterized using microanalysis, various spectral techniques. Spectral studies reveal that the complexes exhibit square planar geometry with ligand coordination through azomethine nitrogen and enolic oxygen. The effects of catalyst dosage, irradiation time and aqueous pH on the photocatalytic activity were studied systematically. The photocatalytic activity was found to be more efficient in the presence of Ni(II) complexes than the Co(II) complex. Possible mechanistic aspects were discussed. PMID:25233028

Gopal Reddy, N B; Murali Krishna, P; Kottam, Nagaraju

2015-02-25

113

Novelmetal-organic photocatalysts: Synthesis, characterization and decomposition of organic dyes  

NASA Astrophysics Data System (ADS)

An efficient method for the photocatalytic degradation of methylene blue in an aqueous medium was developed using metal-organic complexes. Two novel complexes were synthesized using, Schiff base ligand, N?-[(E)-(4-ethylphenyl)methylidene]-4-hydroxybenzohydrazide (HL) and Ni(II) (Complex 1)/Co(II) (Complex 2) chloride respectively. These complexes were characterized using microanalysis, various spectral techniques. Spectral studies reveal that the complexes exhibit square planar geometry with ligand coordination through azomethine nitrogen and enolic oxygen. The effects of catalyst dosage, irradiation time and aqueous pH on the photocatalytic activity were studied systematically. The photocatalytic activity was found to be more efficient in the presence of Ni(II) complexes than the Co(II) complex. Possible mechanistic aspects were discussed.

Gopal Reddy, N. B.; Murali Krishna, P.; Kottam, Nagaraju

2015-02-01

114

Optical modeling of bulk-heterojunction organic solar cells based on squarine dye as electron donor  

NASA Astrophysics Data System (ADS)

The potentiality of a squarine dye (Sq1) for using as electron donor component in bulk heterojunction organic solar cells (BHJ) has been studied from the optical point of view. The soluble n-type fullerene, (6,6)-phenyl C61 butyric acid methyl ester (PC61MB) was chosen as acceptor. Optical modelling based on transfer matrix method was carried out to predict and improve photovoltaic performance of a BHJ device with blended Sq1/PC61MB active layer. The dependence of the absorption and the calculated maximum short circuit photocurrent (Jscmax) on the thickness of the active layer (dact), was investigated for two weight ratios of Sq1 and PC61MB. Thus, the optimal dact was calculated to be about 100 nm, which provides an efficient overlapping of the total absorption with solar spectrum in the range between 580 and 900 nm. Besides, it is found that the insertion of ZnO or C60 spacer layer shifts Jscmax peak to lower dact and significantly enhances Jscmax for active layers with dact < 50 nm, which is mainly due to improved light absorption by a factor of 5 to 10. Simultaneously, for dact <100 nm the optical effect of inserted PEDOT:PSS hole transporting layer is negligible.

Kitova, S.; Stoyanova, D.; Dikova, J.; Kandinska, M.; Vasilev, A.; Angelova, S.

2014-12-01

115

Surface Binding and Organization of Sensitizing Dyes on Metal Oxide Single Crystal Surfaces  

SciTech Connect

Even though investigations of dye-sensitized nanocrystalline semiconductors in solar cells has dominated research on dye-sensitized semiconductors over the past two decades. Single crystal electrodes represent far simpler model systems for studying the sensitization process with a continuing train of studies dating back more than forty years. Even today single crystal surfaces prove to be more controlled experimental models for the study of dye-sensitized semiconductors than the nanocrystalline substrates. We analyzed the scientific advances in the model sensitized single crystal systems that preceded the introduction of nanocrystalline semiconductor electrodes. It then follows the single crystal research to the present, illustrating both their striking simplicity of use and clarity of interpretation relative to nanocrystalline electrodes. Researchers have employed many electrochemical, photochemical and scanning probe techniques for studying monolayer quantities of sensitizing dyes at specific crystallographic faces of different semiconductors. These methods include photochronocoulometry, electronic spectroscopy and flash photolysis of dyes at potential-controlled semiconductor electrodes and the use of total internal reflection methods. In addition, we describe the preparation of surfaces of single crystal SnS2 and TiO2 electrodes to serve as reproducible model systems for charge separation at dye sensitized solar cells. This process involves cleaving the SnS2 electrodes and a photoelectrochemical surface treatment for TiO2 that produces clean surfaces for sensitization (as verified by AFM) resulting in near unity yields for electron transfer from the molecular excited dyes into the conduction band.

Parkinson, Bruce

2010-06-04

116

Aggregation control of organic sensitizers for panchromatic dye co-sensitized solar cells  

NASA Astrophysics Data System (ADS)

The photovoltaic properties of dye co-sensitized solar cells were compared with those of mono-sensitized devices. Co-sensitized TiO2 photo-electrodes were prepared from a phenothiazine chromophore for the RED dye and a squaraine chromophore for the BLUE dye to achieve panchromatic light absorption in dye co-sensitized solar cells (DSSCs). Co-sensitization on the TiO2 photo-electrode could reduce the aggregation of the BLUE dye adsorbed on the TiO2 surface, which led to an enhancement of the short circuit current (Jsc) of the co-sensitized solar cells. The dye co-sensitized solar cells with the RED and BLUE dyes optimized according to the dipping time showed an increase in the photon-to-current efficiency compared to that of the solar cell with a mono-sensitized photo-electrode. The photovoltaic and aggregation properties of the DSSCs were examined by measuring the current-voltage curve, incident photon-to-current efficiency, and electrochemical impedance spectra.

Lee, Chi Hwan; Kim, Sang A.; Jung, Mi Ran; Ahn, Kwang-Soon; Han, Yoon Soo; Kim, Jae Hong

2014-08-01

117

Studies of mechanisms of decay and recovery in organic dye-doped polymers using spatially resolved white light interferometry  

NASA Astrophysics Data System (ADS)

Several organic dyes have been shown to self heal when doped in a polymer matrix. Most measurements to date use optical absorbance, amplified spontaneous emission, or digital imaging as a probe. Each method determines a subset of the relevant parameters. We have constructed a white light interferometric microscope, which measures the absorption spectrum and change in refractive index during decay and recovery simultaneously at multiple points in the material. We report on preliminary measurements and results concerning the microscopes spatial resolution.

Anderson, Benjamin; Bernhardt, Elizabeth; Kuzyk, Mark

2012-10-01

118

High-efficiency orange and tandem white organic light-emitting diodes using phosphorescent dyes with horizontally oriented emitting dipoles.  

PubMed

Tandem white organic light-emitting diodes (WOLEDs) using horizontally oriented phosphorescent dyes in an exciplex-forming co-host are presented, along with an orange OLED. A high external quantum efficiency of 32% is achieved for the orange OLED at 1000 cd m(-2) and the tandem WOLEDs exhibit a high maximum EQE of 54.3% (PE of 63 lm W(-1)). PMID:24923483

Lee, Sunghun; Shin, Hyun; Kim, Jang-Joo

2014-09-01

119

HPLC-DAD-MS analysis of dyes identified in textiles from Mount Athos.  

PubMed

Organic colorants contained in 30 textiles (16th to early 20th century) from the monastery of Simonos Petra (Mount Athos) have been investigated using high-performance liquid chromatography equipped with diode-array detection and mass spectrometry (HPLC-DAD-MS). The components of natural dyes identified in samples treated by the standard HCl dyestuff extraction method were: alizarin, apigenin, butein, carminic acid, chrysoeriol, dcII, dcIV, dcVII, ellagic acid, emodin, fisetin, flavokermesic acid, fustin, genistein, haematein derivative (Hae'), indigotin, indirubin, isoliquiritigenin, isorhamnetin, kaempferide, kaempferol, kermesic acid, luteolin, naringenin, purpurin, quercetin, rhamnazin, rhamnetin, sulfuretin, and type B and type C compounds (last two are markers for Caesalpinia trees). Early, semi-synthetic dyes, for example indigo carmine, fuchsin components, and rhodamine B were identified in objects dated late 19th to early 20th century. A dyestuff extraction method which involves use of TFA, instead of HCl, was applied to selected historical samples, showing that the mild method enables efficient extraction of weld (Reseda luteola L.) and dyer's broom (Genista tinctoria L.) glycosides. The marker compound (Hae') for logwood (Haematoxylum campechianum L.) identification after treatment with HCl was investigated by liquid chromatography coupled to mass spectrometry (LC-MS) in negative electrospray ionization (LC-MS-ESI(-)) mode. LC-MS in negative atmospheric pressure chemical ionization (LC-MS-APCI(-)) mode was used, probably for the first time, to investigate cochineal (Dactylopius coccus Costa) samples. Positive electrospray ionization (LC-MS-ESI(+)) mode was used for identification of fuchsin components. Detailed HPLC-DAD studies were performed on young fustic (Cotinus coggygria Scop.) and Persian berries (Rhamnus trees). PMID:21271239

Mantzouris, Dimitrios; Karapanagiotis, Ioannis; Valianou, Lemonia; Panayiotou, Costas

2011-03-01

120

Novel magnetic Fe3O4@C nanoparticles as adsorbents for removal of organic dyes from aqueous solution.  

PubMed

The magnetic Fe(3)O(4)/C core-shell nanoparticles have been synthesized by a simple strategy and used as adsorbents for removal of organic dyes from aqueous solution. The resulting products are characterized by scanning electron microscope (SEM), energy dispersive X-ray spectrometry (EDX), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectra and Fourier transform infrared spectra (FTIR). Adsorption performances of the nanomaterial adsorbents are tested with removal of methylene blue (MB) and cresol red (CR) from aqueous solution. The effects of solution pH value, adsorption time and capacity of the nanocomposites have been fully investigated. The results reveal that the nanospheres can be easily manipulated by an external magnetic field with high separation efficiency. In addition, the process is clean and safe for purifying water pollution. The prepared Fe(3)O(4)/C complex nanomaterials could thus be used as promising adsorbents for the remove organic dyes, especially, cationic dye, from polluted water. PMID:21813238

Zhang, Zhengyong; Kong, Jilie

2011-10-15

121

Synthesis and characterization of organic dyes with various electron-accepting substituents for p-type dye-sensitized solar cells.  

PubMed

Four new donor-?-acceptor dyes differing in their acceptor group have been synthesized and employed as model systems to study the influence of the acceptor groups on the photophysical properties and in NiO-based p-type dye-sensitized solar cells. UV/Vis absorption spectra showed a broad range of absorption coverage with maxima between 331 and 653?nm. Redox potentials as well as HOMO and LUMO energies of the dyes were determined from cyclic voltammetry measurements and evaluated concerning their potential use as sensitizers in p-type dye-sensitized solar cells (p-DSCs). Quantum-chemical density functional theory calculations gave further insight into the frontier orbital distributions, which are relevant for the electronic processes in p-DSCs. In p-DSCs using an iodide/triiodide-based electrolyte, the polycyclic 9,10-dicyano-acenaphtho[1,2-b]quinoxaline (DCANQ) acceptor-containing dye gave the highest power conversion efficiency of 0.08%, which is comparable to that obtained with the perylenemonoimide (PMI)-containing dye. Interestingly, devices containing the DCANQ-based dye achieve a higher V(OC) of 163?mV compared to 158?mV for the PMI-containing dye. The result was further confirmed by impedance spectroscopic analysis showing higher recombination resistance and thus a lower recombination rate for devices containing the DCANQ dye than for PMI dye-based devices. However, the use of the strong electron-accepting tricyanofurane (TCF) group played a negative role in the device performance, yielding an efficiency of only 0.01% due to a low-lying LUMO energy level, thus resulting in an insufficient driving force for efficient dye regeneration. The results demonstrate that a careful molecular design with a proper choice of the acceptor unit is essential for development of sensitizers for p-DSCs. PMID:25234556

Weidelener, Martin; Powar, Satvasheel; Kast, Hannelore; Yu, Ze; Boix, Pablo P; Li, Chen; Mllen, Klaus; Geiger, Thomas; Kuster, Simon; Nesch, Frank; Bach, Udo; Mishra, Amaresh; Buerle, Peter

2014-11-01

122

A comparative study of non-covalent encapsulation methods for organic dyes into silica nanoparticles  

NASA Astrophysics Data System (ADS)

Numerous luminophores may be encapsulated into silica nanoparticles (< 100 nm) using the reverse microemulsion process. Nevertheless, the behaviour and effect of such luminescent molecules appear to have been much less studied and may possibly prevent the encapsulation process from occurring. Such nanospheres represent attractive nanoplatforms for the development of biotargeted biocompatible luminescent tracers. Physical and chemical properties of the encapsulated molecules may be affected by the nanomatrix. This study examines the synthesis of different types of dispersed silica nanoparticles, the ability of the selected luminophores towards incorporation into the silica matrix of those nanoobjects as well as the photophysical properties of the produced dye-doped silica nanoparticles. The nanoparticles present mean diameters between 40 and 60 nm as shown by TEM analysis. Mainly, the photophysical characteristics of the dyes are retained upon their encapsulation into the silica matrix, leading to fluorescent silica nanoparticles. This feature article surveys recent research progress on the fabrication strategies of these dye-doped silica nanoparticles.

Auger, Aurlien; Samuel, Jorice; Poncelet, Olivier; Raccurt, Olivier

2011-12-01

123

Multi-Layered Anisotropic Films Based on the Azo Dye Brilliant Yellow and Organic Polymers  

NASA Astrophysics Data System (ADS)

A technique for producing multi-layered fi lms containing alternating layers of photo-aligned dichroic azo dye brilliant yellow (BY) dispersed in a matrix of polyvinylpyrrolidone and optically transparent polycyclohexadiene (PCHD) was developed. The optical density of the films depended linearly on the number of layers of dye and its concentration in the initial solutions. It was determined that the surface roughness of the composition BY layer on the PCHD layer was three times less than on single-crystalline silicon substrate (4.8 and 1.5 nm). Multi-layered fi lms based on BY exhibited dichroic absorption and birefringence upon irradiation with linearly polarized light (? = 450 nm).

Chaplanova, Zh. D.; Murauski, A. A.; Rogachev, A. A.; Agabekov, V. E.; Gracheva, E. A.

2013-11-01

124

Facile synthesis of PbWO4: Applications in photoluminescence and photocatalytic degradation of organic dyes under visible light  

NASA Astrophysics Data System (ADS)

Stolzite polymorph of PbWO4 catalyst was prepared by the facile room temperature precipitation method. Structural parameters were refined by the Rietveld analysis using powder X-ray data. PbWO4 was crystallized in the scheelite-type tetragonal structure with space group I41/a (No. 88). Field emission scanning electron microscopy revealed leaf like morphology. Photoluminescence spectra exhibit broad blue emission (425 nm) under the excitation of 356 nm. The photocatalytic degradation of Methylene blue, Rhodamine B and Methyl orange dyes were measured under visible illumination. The 100% dye degradation was observed for MB and RhB dyes within 60 and 105 min. The rate constant was found to be in the decreasing order of MB > RhB > MO which followed the 1st order kinetic mechanism. Therefore, PbWO4 can be a potential candidate for blue component in white LEDs and also acts as a catalyst for the treatment of toxic and non-biodegradable organic pollutants in water.

Saraf, Rohit; Shivakumara, C.; Behera, Sukanti; Nagabhushana, H.; Dhananjaya, N.

2015-02-01

125

Facile synthesis of PbWO4: applications in photoluminescence and photocatalytic degradation of organic dyes under visible light.  

PubMed

Stolzite polymorph of PbWO4 catalyst was prepared by the facile room temperature precipitation method. Structural parameters were refined by the Rietveld analysis using powder X-ray data. PbWO4 was crystallized in the scheelite-type tetragonal structure with space group I41/a (No. 88). Field emission scanning electron microscopy revealed leaf like morphology. Photoluminescence spectra exhibit broad blue emission (425 nm) under the excitation of 356 nm. The photocatalytic degradation of Methylene blue, Rhodamine B and Methyl orange dyes were measured under visible illumination. The 100% dye degradation was observed for MB and RhB dyes within 60 and 105 min. The rate constant was found to be in the decreasing order of MB>RhB>MO which followed the 1st order kinetic mechanism. Therefore, PbWO4 can be a potential candidate for blue component in white LEDs and also acts as a catalyst for the treatment of toxic and non-biodegradable organic pollutants in water. PMID:25448939

Saraf, Rohit; Shivakumara, C; Behera, Sukanti; Nagabhushana, H; Dhananjaya, N

2015-02-01

126

Antenna-coupled high-Tc bolometers for visible and near-infrared detection using organic dyes as light-harvesting layers  

Microsoft Academic Search

Antenna-coupled high-Tc bolometers fabricated from YBa2Cu3O7?? thin films have been prepared using molecular organic dyes. Light-harvesting layers derived from these visible and near-infrared absorbers have been utilized to produce detectors which exhibit wavelength-selective response characteristics in the visible and near-infrared spectral regions. Using such hybrid structures, initial studies documenting efficient energy transfer between molecular dye layers and superconductor surfaces have

David C. Jurbergs; Jianai Zhao; John T. McDevitt

1996-01-01

127

Variation in the concentration of carminic acid produced by Dactylopius coccus (Hemiptera: Dactylopidae) at various maturation stages.  

PubMed

The concentration of carminic acid was found to vary based on the size and life cycle stage of the cochineal, Dactylopius coccus Costa. The concentration of carminic acid in cochineal eggs, nymph I, nymph II, fertilized adults, ovipositing adults, and sterile adults female was measured using capillary electrophoresis, and the total fluorescence of the carminic acid globules was measured using flow cytometry. The smallest sterile adult females had a greater percentage of carminic acid relative to their weight (26.27%; P < 0.001) than adult females in the remaining groups. In general, ovipositing females had a greater percentage of carminic acid than the remainder of the females. Nymph II was the phase that had the smallest percentage of carminic acid. Using flow cytometry, it was demonstrated that ovipositing females had a greater total fluorescence than the other sampled groups (P < 0.05). A positive correlation was found between the percentage of carminic acid and the total fluorescence of the carminic acid globules (r2 = 0.68; P < 0.05). The results of this study, together with others that involve industrial processes, shall allow an improvement of the current classification criteria of the commercial quality of dry cochineal. PMID:25195465

Flores-Alatorre, H L; Abrego-Reyes, V; Reyes-Esparza, J A; Angeles, E; Alba-Hurtado, F

2014-08-01

128

75 FR 81949 - Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Carmine in the Labeling of Wines, Distilled Spirits, and Malt Beverages; Comment Period...Carmine in the Labeling of Wines, Distilled Spirits, and Malt Beverages, a notice of proposed...Lynne J. Omlie on behalf of the Distilled Spirits Council of the United States,...

2010-12-29

129

Organic Dyes Incorporating the Dithieno[3',2':3,4;2?,3?:5,6]benzo[1,2-c]furazan Moiety for Dye-Sensitized Solar Cells.  

PubMed

New D-?-A'-?-A type sensitizers (JH dyes), comprised arylamine as the electron donor, dithieno[3',2':3,4;2?,3?:5,6]benzo[1,2-c]furazan (DTBF) in the conjugated spacer, and 2-cyanoacrylic acid as both the acceptor and anchor, have been synthesized. The JH dyes have broad absorption spectra covering the range of 350 to 600 nm with the highest molar extinction coefficient up to >40?000 M(-1) cm(-1). The dye-sensitized solar cells (DSSCs) fabricated from the dyes exhibited light-to-electricity conversions ranging from 1.42 to 6.18% under simulated AM 1.5 G illumination. Upon adding 10 mM CDCA as the coadsorbent, the best performance cell has the power conversion efficiency of 7.33%, which is close to that of N719-based standard DSSC (7.56%). PMID:25470385

Ni, Jen-Shyang; You, Jian-Hao; Hung, Wei-I; Kao, Wei-Siang; Chou, Hsien-Hsin; Lin, Jiann T

2014-12-24

130

The J-band of organic dyes: lineshape and coherence length  

NASA Astrophysics Data System (ADS)

Self-organised J-aggregates of dye molecules, known for over 60 years, are emerging as remarkably versatile quantum systems with applications in photography, opto-electronics, solar cells, photobiology and as supra-molecular fibres. Recently there has been much effort to achieve quantum entanglement and coherence on the nanoscale in atom traps and quantum dot aggregates (for use in quantum computing). We point out that the excitonic state of the J-aggregate is a text-book case of mesoscopic quantum coherence and entanglement. The establishment of coherence can literally be seen since the dye changes colour dramatically on aggregation due to strong shifts in the absorption spectrum. Here we reproduce in a simple theory the shifts and shapes of optical absorption spectra upon aggregation to a polymer and calculate the coherence length of quantum entanglement of monomer wavefunctions.

Eisfeld, Alexander; Briggs, John S.

2002-07-01

131

A comparative study of non-covalent encapsulation methods for organic dyes into silica nanoparticles.  

PubMed

Numerous luminophores may be encapsulated into silica nanoparticles (< 100 nm) using the reverse microemulsion process. Nevertheless, the behaviour and effect of such luminescent molecules appear to have been much less studied and may possibly prevent the encapsulation process from occurring. Such nanospheres represent attractive nanoplatforms for the development of biotargeted biocompatible luminescent tracers. Physical and chemical properties of the encapsulated molecules may be affected by the nanomatrix. This study examines the synthesis of different types of dispersed silica nanoparticles, the ability of the selected luminophores towards incorporation into the silica matrix of those nanoobjects as well as the photophysical properties of the produced dye-doped silica nanoparticles. The nanoparticles present mean diameters between 40 and 60 nm as shown by TEM analysis. Mainly, the photophysical characteristics of the dyes are retained upon their encapsulation into the silica matrix, leading to fluorescent silica nanoparticles. This feature article surveys recent research progress on the fabrication strategies of these dye-doped silica nanoparticles. PMID:21711855

Auger, Aurlien; Samuel, Jorice; Poncelet, Olivier; Raccurt, Olivier

2011-01-01

132

Smectite clays of Serbia and their application in adsorption of organic dyes  

NASA Astrophysics Data System (ADS)

Colorants and dyes are currently available in over a 100.000 different species and several biggest industries are using them daily in their manufacture processes (textile, cosmetics, food industry, etc.). Since colorants are easily dissoluble in water they pass through filter membranes without further decomposing and in that manner they end up in the environment. The main goal of this work is to apply certain methods in determining the suitability of individual clay in adsorbing and removing colorants from polluted waters. For this study we have chosen four different raw clays from three regions in Serbia: Svrljig (B), Bogovina (Bo) and Slatina-Ub (C and V) and as colorant - methylene blue dye (MB (MERCK, for analytical purposes)). Experiments where carried out to determine the sample structure (XRD and IR), grain size (granulometry), cationic exchange capacity (CEC via spectrophotometry using MB) and adsorption capabilities (spectrophotometry and fluorimetry using MB). XRD and IR data are showing that the samples are smectite clays where samples B i Bo are mainly montmorillonite while C and V are montmorillonite-illite clays. Granulometric distribution results indicate that samples B i Bo have smaller grain size, less that 1? (over 60%) whereas the samples C and V are more coarse grained (40% over 20?). This grain distribution is affecting their specific surface area in the manner that those coarse grained samples have smaller specific surface area. Cationic exchange capacity determined with methylene blue indicate that montmorillonite samples have larger CEC (B = 37 meq/100g, Bo = 50 meq/100g) and montmorillonite-illite samples smaller CEC (V = 5 meq/100g, V = 3 meq/100g). Fluorimetry measurement results gave us a clear distinction between those with higher and smaller adsorption capability. Montmorillonite samples (B and Bo) with higher CEC values and smaller grain size are adsorbing large amounts of methylene blue witch is visible by absence of fluorimetric band corresponding to methylene blue. Montmorillonite-illite samples with smaller CEC values and coarser grain size are adsorbing very small amounts of methylene blue from the suspension which is visible by appearance of the methylene blue band. Untreated, raw smectite clays of Serbia are efficient adsorbent material for removal of dyes from polluted waters. Samples from two regions especially, Bogovina and Svrljig, are showing favorable adsorption results and they are representing good raw materials for purification of waste-waters containing dyes. References: - Jovi?-Jovi?i?, N., Milutinovi?-Nikoli?, A., Greti?, I., Jovanovi?, D.; Organobentonite as efficient textile dye sorbent; Chem. Eng. Technol. 2008, 31, No. 4, 567-574 - uni?, M.J., Milutinovi?-Nikoli?, A.D., Jovi?-Jovi?i?, N.P., Bankovi?, P.T., Mojovi?, Z.D., Manojlovi?, D.D., Jovanovi?, D.M.; Modified bentonite as adsorbent and catalyst for purification of wastewaters containing dyes; Hem. ind. 2010, 64 ,No. 3, 193-199

Miloevi?, Maja; Logar, Mihovil

2014-05-01

133

Increased light harvesting in dye-sensitized solar cells with energy relay dyes  

E-print Network

Increased light harvesting in dye-sensitized solar cells with energy relay dyes Brian E. Hardin1 efficiency when using an energy relay dye (PTCDI) with an organic sensitizing dye (TT1). We estimate on the basis of light harvesting using a sensitizing dye (SD) attached to a wide- bandgap semiconductor1

McGehee, Michael

134

UV light induced photodegradation of organic dye by ZnO nanocatalysts  

SciTech Connect

Ultraviolet light induced photocatalytic activity of ZnO nanocatalyst prepared using a wet chemical precipitation route and mineralization of the methyl orange (MO) dye has been carried out in a photocatalytic reactor. The degradation of the MO was monitored spectrophotometrically and showed a decolorization efficiency of 92% after nine hours of irradiation in the MO-ZnO/UV light system. The blue shifting of maximum peak position of the MO and the formation of extra peak at 247 nm during irradiation time advances revealed that MO degrades in the form of intermediates during the photocatalytic process.

Sumesh, C. K.; Patel, Bhavin [Department of Physical Sciences, P.D. Patel Institute of Applied Sciences, CHARUSAT, Changa-388 421, Gujarat (India); Parekh, Kinnari [Dr. K. C. Patel R and D Centre, CHARUSAT, Changa-388 421, Gujarat (India)

2013-06-03

135

Influence of niobium doping in hierarchically organized titania nanostructure on performance of dye-sensitized solar cells.  

PubMed

Niobium doped hierarchically organized TiO2 nanostructures composed of 20 nm size anatase nanocrystals were synthesized using pulsed laser deposition (PLD). The Nb doping concentration could be facilely controlled by adjusting the concentration of Nb in target materials. We could investigate the influence of Nb doping in the TiO2 photoelectrode on the cell performance of dye-sensitized solar cells (DSSCs) by the exclusion of morphological effects using the prepared Nb-doped TiO2 anostructures. We found no significant change in short circuit current density (Jsc) as a function of Nb doping concentration. However, open circuit voltage (Voc) and fill factor (FF) monotonously decrease with increasing Nb concentration. Dark current characteristics of the DSSCs reveal that the decrease in Voc and FF is attributed to the decrease in shunt resistance due to the increase in conductivity TiO2 by Nb doping. However, electrochemical impedance spectra (EIS) analysis at open circuit condition under illumination showed that the resistance at the TiO2/dye/electrolyte interface increases with Nb concentration, revealing that Nb doping suppress the charge recombination at the interface. In addition, electron life time obtained using characteristic frequency in Bode plot increases from 14 msec to 56 msec with increasing Nb concentration from 0 to 1.2 at%. This implies that the improved light harvesting can be achieved by increasing diffusion length through Nb-doping in the conventional TiO2 photoelectrode. PMID:22905583

Park, Jong Hoon; Noh, Jun Hong; Han, Byung Suh; Shin, Seong Sik; Park, Ik Jae; Kim, Dong Hoe; Hong, Kug Sun

2012-06-01

136

Recycling of agricultural solid waste, coir pith: removal of anions, heavy metals, organics and dyes from water by adsorption onto ZnCl2 activated coir pith carbon.  

PubMed

The abundant lignocellulosic agricultural waste, coir pith is used to develop ZnCl(2) activated carbon and applied to the removal of toxic anions, heavy metals, organic compounds and dyes from water. Sorption of inorganic anions such as nitrate, thiocyanate, selenite, chromium(VI), vanadium(V), sulfate, molybdate, phosphate and heavy metals such as nickel(II) and mercury(II) has been studied. Removal of organics such as resorcinol, 4-nitrophenol, catechol, bisphenol A, 2-aminophenol, quinol, O-cresol, phenol and 2-chlorophenol has also been investigated. Uptake of acidic dyes such as acid brilliant blue, acid violet, basic dyes such as methylene blue, rhodamine B, direct dyes such as direct red 12B, congo red and reactive dyes such as procion red, procion orange were also examined to assess the possible use of the adsorbent for the treatment of contaminated ground water. Favorable conditions for maximum removal of all adsorbates at the adsorbate concentration of 20 mg/L were used. Results show that ZnCl(2) activated coir pith carbon is effective for the removal of toxic pollutants from water. PMID:16406295

Namasivayam, C; Sangeetha, D

2006-07-31

137

Computational design of small organic dyes with strong visible absorption by controlled quinoidization of the thiophene unit  

NASA Astrophysics Data System (ADS)

We present rational design of phenothiazine dyes by controlled quinoidization of the thiophene unit. We systematically study the effect of electron-withdrawing functional groups including pseudo- and super-halogens. We propose a new dye where a fumaronitrile unit induces an increase in the bond length alternation and a concurrent red shift in the absorption spectrum vs. the parent dye. The visible absorption peak is predicted at 520 nm, in CH2Cl2 vs. 450 nm for the parent dye. The LUMO and HOMO levels of the new dye are suitable for injection into TiO2 and regeneration by available redox shuttles, respectively.

Tan, Yi Yin; Tu, Wei Han; Manzhos, Sergei

2014-02-01

138

Measuring Quantum Efficiency of Organic Dyes Encapsulated in Dielectric NanoSpheres  

NASA Astrophysics Data System (ADS)

We present results of a fluorescent quantum efficiency (?) study on the encapsulation of the near infrared dye indocyanine green (ICG) in calcium phosphate (CP) nanoparticles (dia50 nm). The quantum efficiency (?, described as the ratio of photons emitted to photons absorbed) provides a quantitative means of describing the fluorescence of an arbitrary molecule. However, standard quantum efficiency measurement techniques provide only ? of the smallest fluorescing unit -- in the case of a nanoparticle suspension, the nanoparticle itself. This presents a problem in accurately describing the quantum efficiency of fluorophores embedded in a nanoparticle. We have developed a method to determine the quantum efficiency of the constituent fluorescent molecules embedded in such a nanoparticle, which provides a more meaningful comparison with the unencapsulated fluorophore. While applicable to generic systems, we present results obtained by our method for the ICG/CP nanoparticles in phosphate buffer solution, revealing a dramatic improvement in per-molecule ? driven by encapsulation.

Russin, Timothy; Altinoglu, Erhan; Adair, James; Eklund, Peter

2009-03-01

139

Polariton-mediated energy transfer between organic dyes in a strongly coupled optical microcavity  

NASA Astrophysics Data System (ADS)

Strongly coupled optical microcavities containing different exciton states permit the creation of hybrid-polariton modes that can be described in terms of a linear admixture of cavity-photon and the constituent excitons. Such hybrid states have been predicted to have optical properties that are different from their constituent parts, making them a test bed for the exploration of light-matter coupling. Here, we use strong coupling in an optical microcavity to mix the electronic transitions of two J-aggregated molecular dyes and use both non-resonant photoluminescence emission and photoluminescence excitation spectroscopy to show that hybrid-polariton states act as an efficient and ultrafast energy-transfer pathway between the two exciton states. We argue that this type of structure may act as a model system to study energy-transfer processes in biological light-harvesting complexes.

Coles, David M.; Somaschi, Niccolo; Michetti, Paolo; Clark, Caspar; Lagoudakis, Pavlos G.; Savvidis, Pavlos G.; Lidzey, David G.

2014-07-01

140

Photocatalytic degradation of organic dye on porous iron sulfide film surface.  

PubMed

Thin films of nanocrystalline and porous FeS(2) with marcasite phase have been deposited from a greenish-blue iron nitroprusside precursor film, which readily gives FeS(2) on reacting with an aqueous solution of sodium sulfide. High resolution X-ray diffraction (HRXRD) pattern indicated the formation of polycrystalline and orthorhombic (marcasite) phase of FeS(2), whereas the field emission scanning electron microscopy (FESEM) showed the morphology of the films to be consisted of grains of average 25 nm diameter with unevenly distributed numerous pores. Optical characterization (UV-Vis and photoluminescence) revealed significant amount of blueshift in the band gap energy of the deposited material, which is attributed to the strong quantum confinement effect exerted by the FeS(2) nanocrystals. The deposited FeS(2) films showed good photocatalytic activity toward the degradation of Rose Bengal dye and could be found efficient for wastewater treatment. PMID:23218234

Bhar, Sanjib Kumar; Jana, Sumanta; Mondal, Anup; Mukherjee, Nillohit

2013-03-01

141

Metal-free organic sensitizers for use in water-splitting dye-sensitized photoelectrochemical cells.  

PubMed

Solar fuel generation requires the efficient capture and conversion of visible light. In both natural and artificial systems, molecular sensitizers can be tuned to capture, convert, and transfer visible light energy. We demonstrate that a series of metal-free porphyrins can drive photoelectrochemical water splitting under broadband and red light (? > 590 nm) illumination in a dye-sensitized TiO2 solar cell. We report the synthesis, spectral, and electrochemical properties of the sensitizers. Despite slow recombination of photoinjected electrons with oxidized porphyrins, photocurrents are low because of low injection yields and slow electron self-exchange between oxidized porphyrins. The free-base porphyrins are stable under conditions of water photoelectrolysis and in some cases photovoltages in excess of 1 V are observed. PMID:25583488

Swierk, John R; Mndez-Hernndez, Dalvin D; McCool, Nicholas S; Liddell, Paul; Terazono, Yuichi; Pahk, Ian; Tomlin, John J; Oster, Nolan V; Moore, Thomas A; Moore, Ana L; Gust, Devens; Mallouk, Thomas E

2015-02-10

142

Polariton-mediated energy transfer between organic dyes in a strongly coupled optical microcavity.  

PubMed

Strongly coupled optical microcavities containing different exciton states permit the creation of hybrid-polariton modes that can be described in terms of a linear admixture of cavity-photon and the constituent excitons. Such hybrid states have been predicted to have optical properties that are different from their constituent parts, making them a test bed for the exploration of light-matter coupling. Here, we use strong coupling in an optical microcavity to mix the electronic transitions of two J-aggregated molecular dyes and use both non-resonant photoluminescence emission and photoluminescence excitation spectroscopy to show that hybrid-polariton states act as an efficient and ultrafast energy-transfer pathway between the two exciton states. We argue that this type of structure may act as a model system to study energy-transfer processes in biological light-harvesting complexes. PMID:24793357

Coles, David M; Somaschi, Niccolo; Michetti, Paolo; Clark, Caspar; Lagoudakis, Pavlos G; Savvidis, Pavlos G; Lidzey, David G

2014-07-01

143

Fluorescence spectra of organic dyes in solution: a time dependent multilevel approach.  

PubMed

Classical all-atom molecular dynamics (MD) simulations and quantum mechanical (QM) time-dependent density functional theory (TD-DFT) calculations are employed to study the conformational and photophysical properties of the first emitter excited state of tetramethyl-rhodamine iso-thiocyanate fluorophore in aqueous solution. For this purpose, a specific and accurate force field has been parameterised from QM data to model the fluorophore's first bright excited state. During the MD simulations, the consequences of the ???* electronic transition on the structure and microsolvation sphere of the dye has been analysed in some detail and compared to the ground state behaviour. Thereafter, fluorescence has been calculated at the TD-DFT level on configurations sampled from the simulated MD trajectories, allowing us to include time dependent solvent effects in the computed emission spectrum. The latter, when compared with the absorption spectrum, reproduces well the experimental Stokes shift, further validating the proposed multilevel computational procedure. PMID:21127788

Barone, Vincenzo; Bloino, Julien; Monti, Susanna; Pedone, Alfonso; Prampolini, Giacomo

2011-02-14

144

Surface modification with MK-2 organic dye in a ZnO/P3HT hybrid solar cell: Impact on device performance  

NASA Astrophysics Data System (ADS)

The photovoltaic performance of a hybrid ZnO/P3HT heterojunction was improved by modifying the device surface with the MK-2 dye. This organic dye enhanced the compatibility between the polymer and the metal oxide, increased the exciton separation efficiency, and improved the molecular ordering in the charge transport network. The resulting device displayed a substantial enhancement in the photocurrent, open circuit voltage, and fill factor, leading to a 12-fold increase in the power conversion efficiency relative to the unmodified device, from 0.13% to 1.53%.

Kim, Yu Jin; An, Tae Kyu; Oh, Seung-Jeong; Chung, Dae Sung; Park, Chan Eon

2014-07-01

145

Effects of surface modification on dye-sensitized solar cell based on an organic dye with naphtho[2,1-b:3,4-b']dithiophene as the conjugated linker.  

PubMed

We have investigated the effects of surface modification on the dye-sensitized solar cell (DSSC) based on a donor-(?-spacer)-acceptor organic dye. A major challenge for donor-(?-spacer)--acceptor molecules as sensitizers in DSSCs is the fast recombination reactions that occur at both the photoanode (e.g., TiO2) surface and the fluorine-doped tin oxide (FTO) electrode, which presents unfavorable effects on the DSSC performance. The two interfaces of TiO2/electrolyte and FTO/electrolyte are passivated selectively in a DSSC using an organic dye with Naphtho[2,1-b:3,4-b']dithiophene as the conjugated linker and the I(-)/I3(-) electrolyte. The current density-voltage characteristics, the dark current analysis, the open circuit voltage-light intensity dependence, and the transient photovoltage/photocurrent results indicate that the recombination processes are affected strongly by surface passivation under variable light intensity. At high light intensity, the recombination reaction at the TiO2 surface is dominant. In this case, silane passivation of the TiO2 surface can suppress recombination significantly, while the c-TiO2 layer makes little contribution to the reduction of the recombination. At low illumination intensity, the recombination at FTO becomes significant, and the recombination can be reduced by applying a c-TiO2 layer. PMID:24377275

Wang, Xiaoxu; Guo, Lei; Xia, Ping Fang; Zheng, Fan; Wong, Man Shing; Zhu, Zhengtao

2014-02-12

146

Enhanced photocatalytic activity of TiO 2 nanofibers and their flexible composite films: Decomposition of organic dyes and efficient H 2 generation from ethanol-water mixtures  

Microsoft Academic Search

TiO2 nanofibers decorated with Pt and Pd nanoparticles have been synthesized and studied in various photocatalytic processes.\\u000a Excellent photocatalytic behavior in the decomposition of organic dyes in water, degradation of organic stains on the surface\\u000a of flexible freestanding cellulose\\/catalyst composite films and in generation of hydrogen from ethanol using both suspended\\u000a and immobilized catalysts are demonstrated. The performance of the

Ming-Chung Wu; Andrs Spi; Anna Avila; Mria Szab; Jussi Hiltunen; Mika Huuhtanen; Gza Tth; kos Kukovecz; Zoltn Knya; Riitta Keiski; Wei-Fang Su; Heli Jantunen; Krisztin Kords

2011-01-01

147

Optimization of lasing in an inverted-opal titania photonic crystal cavity as an organic solid-state dye-doped laser.  

PubMed

Lasing performance of a dye-doped laser by encapsulating orange fluorescent dye 4-(Dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM) with different concentrations in a highly ordered three-dimensional (3D) inverted-opal titania (TiO2) photonic crystal (PC) microcavity was studied. The lasing threshold and laser quality were improved by optimizing the concentration of the laser dye DCM. When the concentration of DCM is optimized to 10-4??mol/l, the photoluminescence (PL) efficiency of DCM is sufficient to achieve lasing emission and meanwhile no fluorescence quantum quenching occurs. Therefore, the emission spectrum was greatly narrowed and the threshold was significantly improved, which reached 0.8??mJ?pulse-1?cm-2. Our findings are promising results toward the realization of fabricating a highly efficient low-threshold organic laser. PMID:25402981

Zhang, Dingke; Chen, Shijian; Jiang, Maohua; Ye, Lijuan

2014-11-10

148

A microporous anionic metal-organic framework for sensing luminescence of lanthanide(III) ions and selective absorption of dyes by ionic exchange.  

PubMed

Herein, a novel anionic framework with primitive centered cubic (pcu) topology, [(CH3 )2 NH2 ]4 [(Zn4 dttz6 )Zn3 ]?15?DMF?4.5?H2 O, (IFMC-2; H3 dttz=4,5-di(1H-tetrazol-5-yl)-2H-1,2,3-triazole) was solvothermally isolated. A new example of a tetranuclear zinc cluster {Zn4 dttz6 } served as a secondary building unit in IFMC-2. Furthermore, the metal cluster was connected by Zn(II) ions to give rise to a 3D open microporous structure. The lanthanide(III)-loaded metal-organic framework (MOF) materials Ln(3+) @IFMC-2, were successfully prepared by using ion-exchange experiments owing to the anionic framework of IFMC-2. Moreover, the emission spectra of the as-prepared Ln(3+) @IFMC-2 were investigated, and the results suggested that IFMC-2 could be utilized as a potential luminescent probe toward different Ln(3+) ions. Additionally, the absorption ability of IFMC-2 toward ionic dyes was also performed. Cationic dyes can be absorbed, but not neutral and anionic dyes, thus indicating that IFMC-2 exhibits selective absorption toward cationic dyes. Furthermore, the cationic dyes can be gradually released in the presence of NaCl. PMID:24677301

Qin, Jun-Sheng; Zhang, Shu-Ran; Du, Dong-Ying; Shen, Ping; Bao, Shao-Juan; Lan, Ya-Qian; Su, Zhong-Min

2014-05-01

149

Carrier multiplication in semiconductor nanocrystals detected by energy transfer to organic dye molecules  

PubMed Central

Carrier multiplication describes an interesting optical phenomenon in semiconductors whereby more than one electron-hole pair, or exciton, can be simultaneously generated upon absorption of a single high-energy photon. So far, it has been highly debated whether the carrier multiplication efficiency is enhanced in semiconductor nanocrystals as compared with their bulk counterpart. The controversy arises from the fact that the ultrafast optical methods currently used need to correctly account for the false contribution of charged excitons to the carrier multiplication signals. Here we show that this charged exciton issue can be resolved in an energy transfer system, where biexcitons generated in the donor nanocrystals are transferred to the acceptor dyes, leading to an enhanced fluorescence from the latter. With the biexciton Auger and energy transfer lifetime measurements, an average carrier multiplication efficiency of ~17.1% can be roughly estimated in CdSe nanocrystals when the excitation photon energy is ~2.46 times of their energy gap. PMID:23132020

Xiao, Jun; Wang, Ying; Hua, Zheng; Wang, Xiaoyong; Zhang, Chunfeng; Xiao, Min

2012-01-01

150

Carrier multiplication in semiconductor nanocrystals detected by energy transfer to organic dye molecules.  

PubMed

Carrier multiplication describes an interesting optical phenomenon in semiconductors whereby more than one electron-hole pair, or exciton, can be simultaneously generated upon absorption of a single high-energy photon. So far, it has been highly debated whether the carrier multiplication efficiency is enhanced in semiconductor nanocrystals as compared with their bulk counterpart. The controversy arises from the fact that the ultrafast optical methods currently used need to correctly account for the false contribution of charged excitons to the carrier multiplication signals. Here we show that this charged exciton issue can be resolved in an energy transfer system, where biexcitons generated in the donor nanocrystals are transferred to the acceptor dyes, leading to an enhanced fluorescence from the latter. With the biexciton Auger and energy transfer lifetime measurements, an average carrier multiplication efficiency of ~17.1% can be roughly estimated in CdSe nanocrystals when the excitation photon energy is ~2.46 times of their energy gap. PMID:23132020

Xiao, Jun; Wang, Ying; Hua, Zheng; Wang, Xiaoyong; Zhang, Chunfeng; Xiao, Min

2012-01-01

151

Impact of local compressive stress on the optical transitions of single organic dye molecules  

NASA Astrophysics Data System (ADS)

The ability to mechanically control the optical properties of individual molecules is a grand challenge in nanoscience and could enable the manipulation of chemical reactivity at the single-molecule level. In the past, light has been used to alter the emission wavelength of individual molecules or modulate the energy transfer quantum yield between them. Furthermore, tensile stress has been applied to study the force dependence of protein folding/unfolding and of the chemistry and photochemistry of single molecules, although in these mechanical experiments the strength of the weakest bond limits the amount of applicable force. Here, we show that compressive stress modifies the photophysical properties of individual dye molecules. We use an atomic force microscope tip to prod individual molecules adsorbed on a surface and follow the effect of the applied force on the electronic states of the molecule by fluorescence spectroscopy. Applying a localized compressive force on an isolated molecule induces a stress that is redistributed throughout the structure. Accordingly, we observe reversible spectral shifts and even shifts that persist after retracting the microscope tip, which we attribute to transitions to metastable states. Using quantum-mechanical calculations, we show that these photophysical changes can be associated with transitions among the different possible conformers of the adsorbed molecule.

Stttinger, Sven; Hinze, Gerald; Diezemann, Gregor; Oesterling, Ingo; Mllen, Klaus; Basch, Thomas

2014-03-01

152

Organic sensitizers featuring a planar indeno[1,2-b]-thiophene for efficient dye-sensitized solar cells.  

PubMed

An efficient organic sensitizer (JK-306) featuring a planar indeno[1,2-b]thiophene as the ?-linker of a bridging unit for dye-sensitized solar cells (DSSCs) was synthesized. The sensitizer had a strong molar absorption coefficient and a red-shifted absorption band compared with JK-305, which resulted in a significant increase in the short-circuit photocurrent density. We incorporated a highly congested bulky amino group into the 2',4'-dihexyloxybiphenyl-4-yl moiety, an electron donor, to diminish the charge recombination and to prevent aggregation of the sensitizer. Under standard AM 1.5G solar conditions, JK-306-sensitized cells in the presence of co-adsorbents chenodeoxycholic acid (CDCA) and 4-[bis(9,9-dimethyl-9H-fluoren-2-yl)amino]benzoic acid (HC-A), which afforded an overall conversion efficiency of 8.37% and 8.52%, respectively. Upon changing the I(-) /I3 (-) electrolyte to the Co(II) /Co(III) redox couple, the cell gave rise to a significantly improved conversion efficiency of 10.02% with the multifunctional HC-A, which is one of the highest values reported for DSSCs with a cobalt-based electrolyte. Furthermore, the JK-306-based solar cell with a polymer gel electrolyte revealed a high conversion efficiency of 7.61%, which is one of the highest values for cells based on organic sensitizers. PMID:23788486

Lim, Kimin; Ju, Myung Jong; Song, Juman; Choi, In Taek; Do, Kwangsuk; Choi, Hyeju; Song, Kihyung; Kim, Hwan Kyu; Ko, Jaejung

2013-08-01

153

Microdochectomy Assisted by Ultrasound-Guided Indigo Carmine Staining of Intraductal Lesions: A Case Report  

PubMed Central

Spontaneous bloody nipple discharge from a single duct is a significant clinical problem. When performing preoperative marking of the discharging duct, it is sometimes difficult to identify the duct owing to intermittent discharge. Precise preoperative marking of the discharging duct and intraductal lesions is very important to avoid unnecessary wide excision of breast tissue or failure to remove the cause of nipple discharge. We herein present a case of preoperative ultrasound-guided indigo carmine staining in a patient with no discharge on the day of surgery. When a dilated duct is visualized on ultrasound, the targeted duct can be localized using indigo carmine staining, and it is possible to perform a precise minimal volume microdochectomy. PMID:25013442

Jeong, Bo Young; Kwak, Beom Seok

2014-01-01

154

Multiple-state interfacial electron injection competes with excited state relaxation and de-excitation to determine external quantum efficiencies of organic dye-sensitized solar cells.  

PubMed

A comprehensive description of the complicated dynamics of excited state evolution and charge transfer at the photochemical interface in dye-sensitized solar cells is crucial to understand the mechanism of converting solar photons to clean electricity, providing an informative basis for the future development of advanced organic materials. By selecting two triarylamine-based organic donor-acceptor dyes characteristic of the respective benzoic acid and cyanoacrylic acid anchors, in this paper we reveal stepwise excited state relaxations and multiple-state electron injections at a realistic titania/dye/electrolyte interface based upon ultrafast spectroscopic measurements and theoretical simulations. Density functional theory (DFT) and time-dependent DFT calculations show that the optically generated "hot" excited state of the dye molecules can undergo a significant conformational relaxation via multistage torsional motions, and thereby transform into an equilibrium quinonoid structure characteristic of a more planar conjugated backbone. A set of kinetic parameters derived from the target analysis of femtosecond transient absorption spectra have been utilized to estimate the electron injection yield, which is in good accord with the maximum of external quantum efficiencies. PMID:25156537

Zhang, Min; Yang, Lin; Yan, Cancan; Ma, Wentao; Wang, Peng

2014-10-14

155

Straightforward fabrication of stable white LEDs by embedding of inorganic UV-LEDs into bulk polymerized polymethyl-methacrylate doped with organic dyes  

PubMed Central

Stable white-emitting down-converted LEDs are straightforwardly prepared by bulk polymerization of an organic dye doped polymethyl-methacrylate (PMMA) shell directly on top of a highly efficient commercial blue-emitting InGaN LED. Our optimized polymerization procedure allows for extending the form factor of achievable luminescence converter (LUCO) material beyond the conventional thin film form and to directly produce devices with light bulb design. The selected organic dyes, the blue-emitting Coumarin 30 and a red-emitting diketopyrrolopyrrole derivative, exhibit high compatibility with the free radical polymerization reaction of the PMMA matrix and ensure high stability of the final hybrid device. The control of both the thickness of the PMMA shell and the concentration of the dopant dyes allow for fine tuning of the emission color of the LUCO LED and to obtain white light with CIE chromatic coordinates x = 0.32 and y = 0.33, with rendering index as high as 80. This simple and versatile procedure is not dye-exclusive and is therefore extendable to other molecular systems for color-tunable efficient solid-state lighting sources. PMID:24638041

Di Martino, Daniela; Beverina, Luca; Sassi, Mauro; Brovelli, Sergio; Tubino, Riccardo; Meinardi, Francesco

2014-01-01

156

Detection of volatile organic compounds through a sensing film of TiO II doped with organic dyes deposited on an optical fiber  

NASA Astrophysics Data System (ADS)

The necessity of detection and recognition of different types of gases, such as volatile organic compounds, which are frequently found in food and beverage industries among others, requires the development of different types of sensors. In this work, an application of optical fiber for the detection of volatile organic compounds, particularly ethanol is presented. The sensor was constructed removing a portion of the cladding and depositing instead a sensing titanium dioxide (TiO II) film doped with an organic dye (rhodamine 6G) by the sol-gel method. The sensor response was measured in a Teflon chamber where the sample to be measured was injected. A He-Ne laser beam was coupled to the fiber and the variation in the output power was measured which indicates the gas presence. The difference between the output power with and without gas gives a measure of the concentration that exists in the chamber. The experimental results showed that for an ethanol concentration range from 0 to 10500 ppm, the response of the sensor was approximately linear with a correlation coefficient of 0.9924.

Muoz A., S.; Ramos M., J.; Martnez H., C.; Castillo M., J.; Beltrn P., G.; Palomino M., R.

2007-03-01

157

Three N-H functionalized metal-organic frameworks with selective CO2 uptake, dye capture, and catalysis.  

PubMed

Three N-H functionalized metal-organic frameworks, Pb-DDQ, Zn-DDQ, and Cu-DDQ, were synthesized with a new flexible dicarboxylate ligand based on quinoxaline (H2DDQ = N,N'-dibenzoic acid-2,3-diaminoquinoxaline). CO2 adsorptions indicate that Zn-DDQ and Cu-DDQ have greatly enhanced the CO2 uptake due to the opposite N-H groups on pyrazine. With very small adsorption of N2, Cu-DDQ shows high selectivity for CO2 and N2. The three MOFs also have large adsorptions of some selected dyes, while Zn-DDQ and Cu-DDQ with large but different shapes of pores are demonstrated to be promising materials for fast separation of MB/other and CV/other mixtures, respectively. The cyanosilylation of aldehydes and ketones with high yields in a short reaction time for Cu-DDQ indicates that Cu-DDQ has a higher Lewis acidity than the other two MOFs. PMID:24987791

Zhu, Yu; Wang, Yan-Mei; Zhao, Sheng-Yun; Liu, Pan; Wei, Chao; Wu, Yun-Long; Xia, Chang-Kun; Xie, Ji-Min

2014-07-21

158

Preparation of Nanoporous TiO2 for Dye-Sensitized Solar Cell (DSSC) Using Various Dyes  

Microsoft Academic Search

This article reports the development of organic dyes as an attempt to reduce material costs of Dye-Sensitized Solar Cell (DSSC). Indonesia, a country with variety and considerable number of botanical resources, is suitable to perform the research. Indonesian black rice, curcuma, papaya leaf, and the combination were chosen as organic dyes source. Dyes were extracted using organic solvent and adsorbed

Brian Yuliarto; Fahiem Fanani; M. Kasyful Fuadi; Nugraha

2010-01-01

159

Three-photon absorption process in organic dyes enhanced by surface plasmon resonance  

NASA Astrophysics Data System (ADS)

Multi-photon absorption processes have received significant attention from the scientific community during the last decade, mainly because of their potential applications in optical limiting, data storage and biomedical fields. Perhaps, one of the most investigated processes studied so far has been two-photon absorption (2PA). These investigations have resulted in successful applications in all the fields mentioned above. However, 2PA present some limitations in the biomedical field when pumping at typical 2PA wavelengths. In order to overcome these limitations, three-photon absorption (3PA) process has been proposed. However, 3PA in organic molecules has a disadvantage, typical values of sigma3' are small (10-81 cm6s 2/photon2), therefore, 3PA excitation requires high irradiances to induce the promotion of electrons from the ground state to the final excited state. To overcome this obstacle, specific molecules that exhibit large 3PA cross-section must be designed. Thus far, there is a lack of systematic studies that correlate 3PA processes with the molecular structure of organic compounds. In order to fill the existent gap in 3PA molecular engineering, in this dissertation we have investigated the structure/property relationship for a new family of fluorene derivatives with very high three-photon absorption cross-sections. We demonstrated that the symmetric intramolecular charge transfer as well as the pi-electron conjugation length enhances the 3PA cross-section of fluorene derivatives. In addition, we showed that the withdrawing electron character of the attractor groups in a pull-pull geometry proved greater 3PA cross-section. After looking for alternative ways to enhance the effective sigma 3' of organic molecules, we investigated the enhancement of two- and three-photon absorption processes by means of Surface Plasmon. We demonstrated an enhancement of the effective two- and three-photon absorption cross-section of an organic compound of 480 and 30 folds, respectively. We proved that the enhancement is a direct consequence of the electric field enhancement at a metal/buffer interface. Next, motivated by the demands for new materials with enhanced nonlinear optical properties, we studied the 3PA of Hematoporphyrin IX and J-aggregate supramolecular systems. As a result, we were able to propose the use of 3PA in photodynamic therapy using Photofrin, the only drug approved by the FDA for PDT.

Cohanoschi, Ion

2006-07-01

160

Modeling materials and processes in hybrid/organic photovoltaics: from dye-sensitized to perovskite solar cells.  

PubMed

CONSPECTUS: Over the last 2 decades, researchers have invested enormous research effort into hybrid/organic photovoltaics, leading to the recent launch of the first commercial products that use this technology. Dye-sensitized solar cells (DSCs) have shown clear advantages over competing technologies. The top certified efficiency of DSCs exceeds 11%, and the laboratory-cell efficiency is greater than 13%. In 2012, the first reports of high efficiency solid-state DSCs based on organohalide lead perovskites completely revolutionized the field. These materials are used as light absorbers in DSCs and as light-harvesting materials and electron conductors in meso-superstructured and flat heterojunction solar cells and show certified efficiencies that exceed 17%. To effectively compete with conventional photovoltaics, emerging technologies such as DSCs need to achieve higher efficiency and stability, while maintaining low production costs. Many of the advances in the DSC field have relied on the computational design and screening of new materials, with researchers examining material characteristics that can improve device performance or stability. Suitable modeling strategies allow researchers to observe the otherwise inaccessible but crucial heterointerfaces that control the operation of DSCs, offering the opportunity to develop new and more efficient materials and optimize processes. In this Account, we present a unified view of recent computational modeling research examining DSCs, illustrating how the principles and simulation tools used for these systems can also be adapted to study the emerging field of perovskite solar cells. Researchers have widely applied first-principles modeling to the DSC field and, more recently, to perovskite-based solar cells. DFT/TDDFT methods provide the basic framework to describe most of the desired materials and interfacial properties, and Car-Parrinello molecular dynamics allow researchers the further ability to sample local minima and dynamical fluctuations at finite temperatures. However, conventional DFT/TDDFT has some limitations, which can be overcome in part by tailored solutions or using many body perturbation theory within the GW approach, which is however more computationally intensive. Relativistic effects, such as spin-orbit coupling, are also included in simulations since they are fundamental for addressing systems that contain heavy atoms. We illustrate the performance of the proposed simulation toolbox along with the fundamental modeling strategies using selected examples of relevant isolated device constituents, including dye and perovskite absorbers, metal-oxide surfaces and nanoparticles, and hole transporters. We critically assess the accuracy of various computational approaches against the related experimental data. We analyze the representative interfaces that control the operational mechanism of the devices, including dye-sensitized TiO2/hole transporter and organohalide lead perovskite/TiO2, and the results reveal fundamental aspects of the device's operational mechanism. Although the modeling of DSCs is relatively mature, the recent "perovskite storm" has presented new problems and new modeling challenges, such as understanding exciton formation and dissociation at interfaces and carrier recombination in these materials. PMID:24856085

De Angelis, Filippo

2014-11-18

161

Advanced treatment of textile dyeing secondary effluent using magnetic anion exchange resin and its effect on organic fouling in subsequent RO membrane.  

PubMed

Strict regulations are forcing dyeing factory to upgrade existing waste treatment system. In this study, advanced treatment of dyeing secondary effluent by magnetic anion exchange resin (NDMP) was investigated and compared with ultrafiltration (UF); NDMP as a pre-treatment of reverse osmosis (RO) was also studied. NDMP resin (20 mL/L) gave higher removal of dissolved organic carbon (DOC) (83.9%) and colority (94.9%) than UF with a cut-off of 10 kDa (only 48.6% and 44.1%, respectively), showing that NDMP treatment was effective to meet the stringent discharge limit of DOC and colority. Besides, NDMP resin (20 mL/L) as a pretreatment of RO increased the permeate flux by 12.5% and reduced irreversible membrane fouling by 6.6%, but UF pretreatment did not mitigate RO membrane fouling. The results of excitation-emission matrix fluorescence spectra and resin fractions showed that NDMP had more efficient removal than UF for transphilic acid and hydrophilic fraction, such as protein-like organic matters and soluble microbial products, which contributed to a significant proportion of RO membrane fouling. In sum, NDMP resin treatment not only gave effective removal of DOC and colority of dyeing secondary effluent, but exhibited some improvement for RO membrane flux and irreversible fouling. PMID:25463217

Yang, Cheng; Li, Li; Shi, Jialu; Long, Chao; Li, Aimin

2015-03-01

162

Effect of vital dyes on retinal pigmented epithelial cell viability and apoptosis: implications for chromovitrectomy  

PubMed Central

Purpose To investigate in vitro effect of vital dyes on toxicity and apoptosis in a human retinal pigment epithelial (RPE) cell line. Methods ARPE-19 cells were exposed to brilliant blue-BriB, evans blue-EB, bromophenol blue-BroB, indocyanine green-ICG, infracyanine green-IfCG, light green-LG, fast green-FG, indigo carmine-IC and congo red-CR. BSS was used as the control. Five different concentrations and two times were tested. Cell viability was determined by MTS assay and apoptosis by Bax expression on western blot. Results All dyes significantly reduced cell viability after 3 minutes of exposure at all concentrations (p<0.01), except for BriB that was safe at concentrations up to 0.25mg/mL and CR up to 0.05mg/mL, while LG was safe in all concentrations. Toxicity was higher after 30 minutes of exposure. Expression of Bax was upregulated after all dyes exposure, except BriB; ICG had the highest Bax expression (p<0.01). Conclusions Overall the safest dye was BriB followed by LG, IfCG, FG, CR, IC, BroB, RB and ICG. ICG was toxic at all concentrations and exposure times tested. Moreover, BriB was the only dye that did not induce apoptosis in ARPE-19 cells. PMID:24022718

Penha, Fernando M; Pons, Marianne; Costa, Elaine Fiod; Rodrigues, Eduardo B.; Maia, Mauricio; Marin-Castao, Maria E; Farah, Michel Eid

2013-01-01

163

Favorite Demonstration: Demonstrating Indigo Carmine Oxidation-Reduction Reactions--A Choreography for Chemical Reactions  

NSDL National Science Digital Library

The indigo carmine demonstration (Ferguson et al. 1973), also referred to as a traffic-light demonstration (Flinn Scientific 2007a), is an example of a set of oxidation-reduction reactions that occurs within one solution. This type of demonstration can be used to introduce the concept of chemical reaction to undergraduate nonscience majors. Through their observations guided by the instructor, students begin to develop and construct the following concepts: color changes, reaction rates, reversible reactions, energy requirements (endothermic/exothermic), and equilibrium.

Majerich, David M.; Schmuckler, Joseph S.

2008-03-01

164

Enhanced electrochromic properties of a polypyrrole-indigo carmine-gold nanoparticles nanocomposite.  

PubMed

An indigo carmine doped polypyrrole embedded with gold nanoparticles nanocomposite (PPy-IC-Aunanop) was synthesized by in situ electrochemical polymerization of polypyrrole in the presence of HAuCl4. The nanocomposite was characterized by in situ spectroelectrochemical experiments to study the effect of embedded gold nanoparticles on the electrochromic properties of the material. The results show the formation of a nanocomposite presenting enhanced electrochromic and optical properties, higher electroactivity and 10% lower band-gap energies. The PPy-IC-Aunanop presented a two-fold increase in optical contrast when compared to PPy-IC, in addition to better optical stability. PMID:25418577

Loguercio, L F; Alves, C C; Thesing, A; Ferreira, J

2014-12-10

165

TiO2 Immobilized on Manihot Carbon: Optimal Preparation and Evaluation of Its Activity in the Decomposition of Indigo Carmine.  

PubMed

Applications of carbon-TiO2 materials have attracted attention in nanotechnology due to their synergic effects. We report the immobilization of TiO2 on carbon prepared from residues of the plant Manihot, commercial TiO2 and glycerol. The objective was to obtain a moderate loading of the anatase phase by preserving the carbonaceous external surface and micropores of the composite. Two preparation methods were compared, including mixing dry precursors and immobilization using a glycerol slurry. The evaluation of the micropore blocking was performed using nitrogen adsorption isotherms. The results indicated that it was possible to use Manihot residues and glycerol to prepare an anatase-containing material with a basic surface and a significant SBET value. The activities of the prepared materials were tested in a decomposition assay of indigo carmine. The TiO2/carbon eliminated nearly 100% of the dye under UV irradiation using the optimal conditions found by a Taguchi L4 orthogonal array considering the specific surface, temperature and initial concentration. The reaction was monitored by UV-Vis spectrophotometry and LC-ESI-(Qq)-TOF-MS, enabling the identification of some intermediates. No isatin-5-sulfonic acid was detected after a 60 min photocatalytic reaction, and three sulfonated aromatic amines, including 4-amino-3-hydroxybenzenesulfonic acid, 2-(2-amino-5-sulfophenyl)-2-oxoacetic acid and 2-amino-5-sulfobenzoic acid, were present in the reaction mixture. PMID:25588214

Antonio-Cisneros, Cynthia M; Dvila-Jimnez, Martn M; Elizalde-Gonzlez, Mara P; Garca-Daz, Esmeralda

2014-01-01

166

TiO2 Immobilized on Manihot Carbon: Optimal Preparation and Evaluation of Its Activity in the Decomposition of Indigo Carmine  

PubMed Central

Applications of carbon-TiO2 materials have attracted attention in nanotechnology due to their synergic effects. We report the immobilization of TiO2 on carbon prepared from residues of the plant Manihot, commercial TiO2 and glycerol. The objective was to obtain a moderate loading of the anatase phase by preserving the carbonaceous external surface and micropores of the composite. Two preparation methods were compared, including mixing dry precursors and immobilization using a glycerol slurry. The evaluation of the micropore blocking was performed using nitrogen adsorption isotherms. The results indicated that it was possible to use Manihot residues and glycerol to prepare an anatase-containing material with a basic surface and a significant SBET value. The activities of the prepared materials were tested in a decomposition assay of indigo carmine. The TiO2/carbon eliminated nearly 100% of the dye under UV irradiation using the optimal conditions found by a Taguchi L4 orthogonal array considering the specific surface, temperature and initial concentration. The reaction was monitored by UV-Vis spectrophotometry and LC-ESI-(Qq)-TOF-MS, enabling the identification of some intermediates. No isatin-5-sulfonic acid was detected after a 60 min photocatalytic reaction, and three sulfonated aromatic amines, including 4-amino-3-hydroxybenzenesulfonic acid, 2-(2-amino-5-sulfophenyl)-2-oxoacetic acid and 2-amino-5-sulfobenzoic acid, were present in the reaction mixture. PMID:25588214

Antonio-Cisneros, Cynthia M.; Dvila-Jimnez, Martn M.; Elizalde-Gonzlez, Mara P.; Garca-Daz, Esmeralda

2015-01-01

167

77 FR 22485 - Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt...  

Federal Register 2010, 2011, 2012, 2013, 2014

...one or both of these color additives. This rule responds to a...products that contain these color additives. DATES: Effective Date...statements relating to age, manufacturing processes, analyses, guarantees...extract and carmine are color additives that are permitted for...

2012-04-16

168

76 FR 3584 - Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt...  

Federal Register 2010, 2011, 2012, 2013, 2014

...TTB-2010-0008; Notice No. 111] RIN 1513-AB79 Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt Beverages Correction In proposed rule document 2010-27733 beginning on page 67669 in the issue of...

2011-01-20

169

Adsorption kinetics and isotherm of anionic dyes onto organo-bentonite from single and multisolute systems.  

PubMed

The performances of polydiallydimethylammonium modified bentonite (PDADMA-bentonite) as an adsorbent to remove anionic dyes, namely Acid Scarlet GR (AS-GR), Acid Turquoise Blue 2G (ATB-2G) and Indigo Carmine (IC), were investigated in single, binary and ternary dye systems. In adsorption from single dye solutions with initial concentration of 100 micromol/L, the dosage of PDADMA-bentonite needed to remove 95% dye was 0.42, 0.68 and 0.75 g/L for AS-GR, ATB-2G and IC, respectively. The adsorption isotherms of the three dyes obeyed the Langmuir isotherm model with the equilibrium constants of 0.372, 0.629 and 4.31 L/micromol, the saturation adsorption amount of 176.3, 149.2 and 228.7 micromol/g for ATB-2G, IC and AS-GR, respectively. In adsorption from mixed dye solutions, the isotherm of each individual dye followed an expanded Langmuir isotherm model and the relationship between the total amount of dyes adsorbed and the total equilibrium dye concentration was interpreted well by Langmuir isotherm model. In the region of insufficient dosage of PDADMA-bentonite, the dye with a larger affinity was preferentially removed by adsorption. Desorption was observed in the kinetic curve of the dye with lower affinity on PDADMA-bentonite surface by the competitive adsorption. The kinetics in single dye solution and the total adsorption of dyes in binary and ternary dye systems nicely followed pseudo-second-order kinetic model. PMID:19631461

Shen, Dazhong; Fan, Jianxin; Zhou, Weizhi; Gao, Baoyu; Yue, Qinyan; Kang, Qi

2009-12-15

170

ASSESSMENT OF POTENTIAL TOXIC RELEASES FROM LEATHER INDUSTRY DYEING OPERATIONS  

EPA Science Inventory

The study focused on the organic dyes released to the environment in the wastewaters from leather dyeing operations. Basically, three types of dyes--acid, basic, and direct--are used, although the number of different dyes are well over 50, and the number of formulations used at a...

171

Photostability of dye molecules trapped in solid matrices  

E-print Network

, chemical, mechanical, and optical properties. Effi- cient solid-state dye lasers were recently obtained of the absence of dye reservoirs and circulation systems in solid-state dye lasers, photostability is a critical organic laser dyes improves when molecules are trapped in solid matrices.6­9 Nevertheless, be- cause

Boyer, Edmond

172

Organic fluorescent dyes supported on activated boron nitride: a promising blue light excited phosphors for high-performance white light-emitting diodes.  

PubMed

We report an effective and rare-earth free light conversion material synthesized via a facile fabrication route, in which organic fluorescent dyes, i.e. Rhodamine B (RhB) and fluorescein isothiocyanate (FITC) are embedded into activated boron nitride (?BN) to form a composite phosphor. The composite phosphor shows highly efficient Frster resonance energy transfer and greatly improved thermal stability, and can emit at broad visible wavelengths of 500-650?nm under the 466?nm blue-light excitation. By packaging of the composite phosphors and a blue light-emitting diode (LED) chip with transparent epoxy resin, white LED with excellent thermal conductivity, current stability and optical performance can be realized, i.e. a thermal conductivity of 0.36?W/mk, a Commission Internationale de 1'Eclairage color coordinates of (0.32, 0.34), and a luminous efficiency of 21.6?lmW(-1). Our research opens the door toward to the practical long-life organic fluorescent dyes-based white LEDs. PMID:25682730

Li, Jie; Lin, Jing; Huang, Yang; Xu, Xuewen; Liu, Zhenya; Xue, Yanming; Ding, Xiaoxia; Luo, Han; Jin, Peng; Zhang, Jun; Zou, Jin; Tang, Chengchun

2015-01-01

173

A photo-induced electron transfer study of an organic dye anchored on the surfaces of TiO2 nanotubes and nanoparticles.  

PubMed

We report on femtosecond-nanosecond (fs-ns) studies of the triphenylamine organic dye (TPC1) interacting with titania nanoparticles of different sizes, nanotubes and nanorods. We used time-resolved emission and absorption spectroscopy to measure the photoinduced dynamics of forward and back electron transfer processes taking place in TPC1-titania complexes in acetonitrile (ACN) and dichloromethane (DCM) solutions. We observed that the electron injection from the dye to titania occurs in a multi-exponential way with the main contribution of 100 fs from the hot excited charge-transfer state of anchored TPC1. This process competes with the relaxation of the excited state, mainly governed by solvation, that takes place with average time constants of 400 fs in ACN and 1.3 ps in DCM solutions. A minor contribution to the electron injection process takes place with longer time constants of about 1-10 ps from the relaxed excited state of TPC1. The latter times and their contribution do not depend on the size of the nanoparticles, but are substantially smaller in the case of nanotubes (1-3 ps), probably due to the caging effect. The contribution is also smaller in DCM than in ACN. The efficient back recombination takes place also in a multi-exponential way with times of 1 ps, 15 ps and 1 ns, and only 20-30% of the initial injected electrons in the conduction band are left within the first 1 ns after excitation. The faster recombination rates are suggested due to those originating from the free electrons in the conduction band of titania or the electrons in the shallow trap states, while the slower recombination is due to the electrons in the deep trap states. The results reported here should be relevant to a better understanding of the photobehaviour of an organic dye with promising potential for use in solar cells. They should also help to determine the important factors that limit the efficiency of solar cells based on the triphenylamine-based dyes for solar energy conversion. PMID:21229164

Zi?ek, Marcin; Tacchini, Ignacio; Martnez, M Teresa; Yang, Xichuan; Sun, Licheng; Douhal, Abderrazzak

2011-03-01

174

Dye Painting with Fiber Reactive Dyes  

ERIC Educational Resources Information Center

In her description of how to use dyes directly onto fabrics the author lists materials to be used, directions for mixing dyes, techniques for applying dyes, references for additional reading and sources for dye materials. Preceding the activity with several lessons in design and other textile techniques with the dye process will ensure a

Benjamin-Murray, Betsy

1977-01-01

175

Study of nonlinear refraction of organic dye by Z-scan technique using He-Ne laser  

SciTech Connect

Laser induced third-order nonlinear optical responses of Brilliant Green solution has been investigated by utilizing single beam Z-scan technique with a continuous-wave He-Ne laser radiation at 632.8 nm. It was observed that the material exhibits self-defocusing type optical nonlinearity. The measurements of nonlinear refraction were carried out at different dye concentrations and found that the increase in solution concentration leads to the linear increase of the nonlinear refractive index. The experimental results confirm great potential of the Brilliant Green for the application in nonlinear optical devices.

Medhekar, S.; Kumar, R.; Mukherjee, S.; Choubey, R. K. [Dept. of Applied Physics, Birla Institute of Technology, Mesra, Ranchi - 835215, Jharkhand (India)

2013-02-05

176

J-aggregates of organic dye molecules complexed with iron oxide nanoparticles for imaging-guided photothermal therapy under 915-nm light.  

PubMed

Recently, the development of nano-theranostic agents aiming at imaging guided therapy has received great attention. In this work, a near-infrared (NIR) heptamethine indocyanine dye, IR825, in the presence of cationic polymer, polyallylamine hydrochloride (PAH), forms J-aggregates with red-shifted and significantly enhanced absorbance. After further complexing with ultra-small iron oxide nanoparticles (IONPs) and the followed functionalization with polyethylene glycol (PEG), the obtained IR825@PAH-IONP-PEG composite nanoparticles are highly stable in different physiological media. With a sharp absorbance peak, IR825@PAH-IONP-PEG can serve as an effective photothermal agent under laser irradiation at 915 nm, which appears to be optimal in photothermal therapy application considering its improved tissue penetration compared with 808-nm light and much lower water heating in comparison to 980-nm light. As revealed by magnetic resonance (MR) imaging, those nanoparticles after intravenous injection exhibit high tumor accumulation, which is then harnessed for in vivo photothermal ablation of tumors, achieving excellent therapeutic efficacy in a mouse tumor model. This study demonstrates for the first time that J-aggregates of organic dye molecules are an interesting class of photothermal material, which when combined with other imageable nanoprobes could serve as a theranostic agent for imaging-guided photothermal therapy of cancer. PMID:24976309

Song, Xuejiao; Gong, Hua; Liu, Teng; Cheng, Liang; Wang, Chao; Sun, Xiaoqi; Liang, Chao; Liu, Zhuang

2014-11-12

177

Layered double hydroxide-carbon dot composite: high-performance adsorbent for removal of anionic organic dye.  

PubMed

It would be of significance to design a green composite for efficient removal of contaminants. Herein, we fabricated a facile and environmentally friendly composite via direct assembly of surface passivated carbon dots with abundant oxygen-containing functional groups on the surface of the positively charged layered double hydroxide (LDH). The resulting LDH-carbon dot composites were characterized by X-ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy, high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), and N2 adsorption-desorption technique. The adsorption performances of the resulting LDH-carbon dot composites were evaluated for the removal of anionic methyl blue dye. Taking advantage of the combined benefits of LDH and carbon dots, the as-prepared composites exhibited high uptake capability of methyl blue (185 mg/g). The adsorption behavior of this new adsorbent fitted well with Langmuir isotherm and the pseudo-second-order kinetic model. The reasons for the excellent adsorption capacity of methyl blue on the surface of the LDH-carbon dot hybrid were further discussed. A probable mechanism was speculated to involve the cooperative contributions of hydrogen bonding between methyl blue and carbon dots and electrostatic attraction between methyl blue and LDH, in the adsorption process. This work is anticipated to open up new possibilities in fabricating LDH-carbon dot materials in dealing with anionic dye pollutants. PMID:25313875

Zhang, Manlin; Yao, Qingfeng; Lu, Chao; Li, Zenghe; Wang, Wenxing

2014-11-26

178

Historical aspects and evolution of the application of vital dyes in vitreoretinal surgery and chromovitrectomy.  

PubMed

Lobeck and coworkers performed the first intravitreal application of vital dyes to visualize preretinal structures in 1932. Since then numerous investigators in the 20th century examined the use of biological stains through the endovenous, subretinal and intravitreal delivery route in order to identify vitreoretinal tissues and breaks. However, in the year 2000, a new surgical approach, recently coined chromovitrectomy, has arisen, which consists in the intraoperative application of vital dyes during vitrectomy. Initially fluorescein, and more recently indocyanine green, trypan blue, bromophenol blue, triamcinolone acetonide and patent blue have been used for the staining of preretinal membranes and tissues. Currently, many vital stains are under evaluation in animals for future clinical application during chromovitrectomy such as indigo carmine or light green. In this paper, several historical considerations in regard to the application of vital dyes in chromovitrectomy are discussed. PMID:18535378

Rodrigues, Eduardo B; Penha, Fernando M; Furlani, Bruno; Meyer, Carsten H; Maia, Mauricio; Farah, Michel E

2008-01-01

179

A Reverse Phase HPLC Method to Determine Six Food Dyes Using Buffered Mobile Phase  

Microsoft Academic Search

A reverse phase high performance liquid chromatographic (HPLC) method to determine six food dyes (Sunset Yellow (E-110), Carminic acid (E-120) Carmoisine (E-122), Amaranth (E-123), Ponceau 4R (E-124) and Erythrosine (E-127) is developed in this paper. The separation was made on a Nova-Pack C18 column using methanol -NaH2PO4\\/Na2HPO4 pH=7 buffer solution 0.1M as mobile phase with an elution gradient system. The

J. J. Berzas-Nevado; C. Guiberteau-Cabanillas; A. M. Contento-Salcedo

1998-01-01

180

Investigation of energy transfer and charge trapping in dye-doped organic light-emitting diodes by magneto-electroluminescence measurement  

NASA Astrophysics Data System (ADS)

We investigated the energy transfer and charge trapping (CT) in dye-doped organic light-emitting devices by using the magneto-electroluminescence as a tool. An intra-molecular charge-transfer fluorescent material N,N-diphenyl-4-(9-phenylnaphtho-[2,3-c][1,2,5]thiadiazol-4-yl)aniline was selected as the guest emitter. The tri-(8-hydroxyquinoline)-aluminum and 1,3-bis(9-carbazolyl)benzene were selected as the hosts. Our results demonstrate that as the energy difference between the HOMO (highest occupied molecular orbital)/LUMO (lowest unoccupied molecular orbital) of the host and the guest (?EHOMO/?ELUMO) increases, the CT becomes more dominant, and the CT cannot be ignored even when the ?EHOMO/?ELUMO is small and the emission spectrum of the host overlaps the absorption spectrum of the guest well.

Peng, Qiming; Gao, Na; Li, Weijun; Chen, Ping; Li, Feng; Ma, Yuguang

2013-05-01

181

Effects of neem ( Azadirachta indica ) seed kernel extracts from different solvents on the carmine spider mite, Tetranychus cinnabarinus  

Microsoft Academic Search

Extracts of neem (Azadirachta indica A. Juss) seed kernels prepared from various solvents affected the behavior and fecundity of the carmine spider mite,Tetranychus cinnabarinus (Boisd.).\\u000a \\u000a Bean leaf discs freshly sprayed with different concentrations of the extracts strongly repelled the females from the treated\\u000a leaves and egg-laying was reduced. On the basis of EC 50s for both parameters, the order of

K. R. S. Ascher

1983-01-01

182

Water-dispersible, pH-stable and highly-luminescent organic dye nanoparticles with amplified emissions for in vitro and in vivo bioimaging.  

PubMed

A new strategy is presented for using doped small-molecule organic nanoparticles (NPs) to achieve high-performance fluorescent probes with strong brightness, large Stokes shifts and tunable emissions for in vitro and in vivo imaging. The host organic NPs are used not only as carriers to encapsulate different doped dyes, but also as fluorescence resonance energy transfer donors to couple with the doped dyes (as acceptors) to achieve multicolor luminescence with amplified emissions (AE). The resulting optimum green emitting NPs show high brightness with quantum yield (QY) of up to 45% and AE of 12 times; and the red emitting NPs show QY of 14% and AE of 10 times. These highly-luminescent doped NPs can be further surface modified with poly(maleic anhydride-alt-1-octadecene)-polyethylene glycol (C18PMH-PEG), endowing them with excellent water dispersibility and robust stability in various bio-environments covering wide pH values from 2 to 10. In this study, cytotoxicity studies and folic acid targeted cellular imaging of these multicolor probes are carried out to demonstrate their potential for in vitro imaging. On this basis, applications of the NP probes in in vivo and ex vivo imaging are also investigated. Intense fluorescent signals of the doped NPs are distinctly, selectively and spatially resolved in tumor sites with high sensitivity, due to the preferential accumulation of the NPs in tumor sites through the passive enhanced permeability and retention effect. The results clearly indicate that these doped NPs are promising fluorescent probes for biomedical applications. PMID:24318966

Yu, Jia; Diao, Xiaojun; Zhang, Xiujuan; Chen, Xianfeng; Hao, Xiaojun; Li, Wei; Zhang, Xiaohong; Lee, Chun-Sing

2014-03-26

183

Increased light harvesting in dye-sensitized solar cells with energy relay dyes  

NASA Astrophysics Data System (ADS)

Conventional dye-sensitized solar cells have excellent charge collection efficiencies, high open-circuit voltages and good fill factors. However, dye-sensitized solar cells do not completely absorb all of the photons from the visible and near-infrared domain and consequently have lower short-circuit photocurrent densities than inorganic photovoltaic devices. Here, we present a new design where high-energy photons are absorbed by highly photoluminescent chromophores unattached to the titania and undergo Frster resonant energy transfer to the sensitizing dye. This novel architecture allows for broader spectral absorption, an increase in dye loading, and relaxes the design requirements for the sensitizing dye. We demonstrate a 26% increase in power conversion efficiency when using an energy relay dye (PTCDI) with an organic sensitizing dye (TT1). We estimate the average excitation transfer efficiency in this system to be at least 47%. This system offers a viable pathway to develop more efficient dye-sensitized solar cells.

Hardin, Brian E.; Hoke, Eric T.; Armstrong, Paul B.; Yum, Jun-Ho; Comte, Pascal; Torres, Toms; Frchet, Jean M. J.; Nazeeruddin, Md Khaja; Grtzel, Michael; McGehee, Michael D.

2009-07-01

184

Vibrational spectroscopy to study degradation of natural dyes. Assessment of oxygen-free cassette for safe exposition of artefacts.  

PubMed

An important issue connected with conservation chemistry is how to improve the storage and exposure conditions in order to suppress the fading and degradation of dyes and other components of paintings. Although the oxygen-free exposure cassettes are commonly known in museums, there is still lack of information in the literature about the effect of anoxic conditions on the degradation of dyes. This study is an attempt to start a database formation on the dyes degradation. Five commercial dyes (indigo, dragon's blood, curcumin, madder, carminic acid) were submitted to accelerated ageing by exposure to intensive light in the visible range in both oxygen-free (anoxia) and -rich conditions. Degradation of the samples was investigated by several analytical techniques (attenuated total reflectance infrared spectroscopy, Raman spectroscopy, reflectance UV-Vis spectroscopy, X-ray fluorescence spectroscopy and optical microscopy). The conclusions are based on the estimators (derived from the determination of colour differences from Vis spectra and from the changes in FTIR and Raman vibrational bands intensity). According to them, only indigo, dragon's blood and curcumin show greater stability in anoxic conditions in comparison with oxygen-rich ones while madder, carminic acid undergo greater degradation. PMID:21165610

Koperska, Monika; ?ojewski, Tomasz; ?ojewska, Joanna

2011-03-01

185

THERMOSPRAY IONIZATION AND TANDEM MASS SPECTROMETRY OF DYES  

EPA Science Inventory

Sixteen commercial dye samples and three liquid wastes from organic pigment and dye manufacture have been characterized without prior chromatography by thermospray ionization and low energy collision-activated dissociation of protonated molecules using a triple quadrupole mass sp...

186

Identification and characterization of artists' red dyes and their mixtures by surface-enhanced Raman spectroscopy.  

PubMed

Silver film over nanospheres (AgFONs) were successfully employed as surface-enhanced Raman spectroscopy (SERS) substrates to characterize several artists' red dyes including: alizarin, purpurin, carminic acid, cochineal, and lac dye. Spectra were collected on sample volumes (1 x 10(-6) M or 15 ng/microL) similar to those that would be found in a museum setting and were found to be higher in resolution and consistency than those collected on silver island films (AgIFs). In fact, to the best of the authors' knowledge, this work presents the highest resolution spectrum of the artists' material cochineal to date. In order to determine an optimized SERS system for dye identification, experiments were conducted in which laser excitation wavelengths were matched with correlating AgFON localized surface plasmon resonance (LSPR) maxima. Enhancements of approximately two orders of magnitude were seen when resonance SERS conditions were met in comparison to non-resonance SERS conditions. Finally, because most samples collected in a museum contain multiple dyestuffs, AgFONs were employed to simultaneously identify individual dyes within several dye mixtures. These results indicate that AgFONs have great potential to be used to identify not only real artwork samples containing a single dye but also samples containing dyes mixtures. PMID:17910797

Whitney, Alyson V; Casadio, Francesca; Van Duyne, Richard P

2007-09-01

187

Discoloration of Indigo Carmine Using Aqueous Extracts from Vegetables and Vegetable Residues as Enzyme Sources  

PubMed Central

Several vegetables and vegetable residues were used as sources of enzymes capable to discolor indigo carmine (IC), completely or partially. Complete discoloration was achieved with aqueous extracts of green pea seeds and peels of green pea, cucumber, and kohlrabi, as well as spring onion leaves. The source of polyphenol oxidase (PPO), pH, time, and aeration is fundamental for the discoloration process catalyzed by PPO. The PPO present in the aqueous extract of green pea seeds was able to degrade 3,000?ppm of IC at a pH of 7.6 and magnetic stirring at 1,800?rpm in about 36?h. In addition, at 1,800?rpm and a pH of 7.6, this extract discolored 300?ppm of IC in 1:40?h; in the presence of 10% NaCl, the discoloration was complete in 5:50?h, whereas it was completed in 4:30?h with 5% NaCl and 2% laundry soap. PMID:24151588

Sols, A.; Perea, F.; Sols, M.; Manjarrez, N.; Prez, H. I.; Cassani, J.

2013-01-01

188

Novel polymer gel electrolyte with organic solvents for quasi-solid-state dye-sensitized solar cells.  

PubMed

A cross-linked copolymer was previously synthesized from poly(oxyethylene) diamine (POE-amine) and an aromatic anhydride and cured to generate an amide-imide cross-linking structure. The copolymer containing several chemical groups such as POE, amido acids, and imide, enabled to absorb liquid electrolytes in methoxypropionitrile (MPN) for suitable uses in dye-sensitized solar cells. To establish the advantages of polymer gel electrolytes (PGE), the same copolymer was studied by using different electrolyte solvents including propylene carbonate (PC), dimethylformamide, and N-methyl-2-pyrrolidone, and shown their long-term stability. The morphology of the copolymer after absorbing liquid electrolytes in these solvents was proven the same as a 3D interconnected nanochannels, evidenced field emission-scanning electron microscopy. Among these solvents, PC was selected as the optimized PGE, which demostrated a higher power conversion efficiency (8.31%) than that of the liquid electrolyte (7.89%). In particular, the long-term stability of only a 5% decrease in the cell efficiency after 1000 h of testing was achieved. It was proven the developed copolymer as PGE was versatile for different solvents showing high efficiency and long-term durability. PMID:25296883

Shen, Sheng-Yen; Dong, Rui-Xuan; Shih, Po-Ta; Ramamurthy, Vittal; Lin, Jiang-Jen; Ho, Kuo-Chuan

2014-11-12

189

Dye laser amplifier  

DOEpatents

An improved dye laser amplifier is disclosed. The efficiency of the dye laser amplifier is increased significantly by increasing the power of a dye beam as it passes from an input window to an output window within the dye chamber, while maintaining the intensity of the dye beam constant. 3 figs.

Moses, E.I.

1992-12-01

190

In vivo and in vitro decolorization of synthetic dyes by laccase from solid state fermentation with Trametes sp. SYBC-L4.  

PubMed

Synthetic decolorization of dyes through solid cassava residue substrate fermentation with Trametes sp. SYBC-L4 via in vivo and in vitro processes was investigated in this study. Effects of pH and mediator (1-hydroxybenzotriazole, HBT) concentration on dyes decolorization were evaluated. In vitro, decolorization ratios of dyes differed considerably in pH and increased with the increasing of HBT concentration. Crude laccase (50 U/L) derived from Trametes sp. SYBC-L4 decolorized 67.911.25% Congo red (100mg/L), 94.581.05% aniline blue (100mg/L) and 99.020.54% indigo carmine (100mg/L) with 2.5mM HBT at pH 4.5 in 36h of incubation. In vivo, decolorization ratios of dyes were not enhanced by usage of the mediator. After 10days of fermentation, decolorization ratio of Congo red (1,000mg/kg), aniline blue (1,000mg/kg) and indigo carmine (1,000mg/kg) was 57.820.84, 92.531.12 and 97.261.92% without the usage of mediator at pH 4.5, respectively. Moreover, there was no obvious difference between the in vivo decolorization of aniline blue and indigo carmine in the pH range of 3.0-9.0. Results showed that Trametes sp. SYBC-L4 had great potential to be used for dyes decolorization via in vivo and in vitro processes. Moreover, in terms of pH range and mediator, in vivo decolorization with Trametes sp. SYBC-L4 was more advantageous since laccase mediator was needless and the applicable range of pH was broader. PMID:24951916

Li, Hui-Xing; Zhang, Rui-Jing; Tang, Lei; Zhang, Jian-Hua; Mao, Zhong-Gui

2014-12-01

191

A near-infrared dithieno[2,3-a:3',2'-c]phenazine-based organic co-sensitizer for highly efficient and stable quasi-solid-state dye-sensitized solar cells.  

PubMed

A novel near-infrared (NIR) organic sensitizer FNE53 with a strong electron-withdrawing unit, dithieno[2,3-a:3',2'-c]phenazine, has been designed and synthesized for quasi-solid-state dye-sensitized solar cells (DSSCs). By simply fusing the two thiophene rings on quinoxaline unit in sensitizer FNE48, the intramolecular charge transfer (ICT) band bathochromically shifts from 542 nm for FNE48 to 629 nm for FNE53 in toluene solution. The absorption spectrum of sensitizer FNE53 covers the whole visible region and extends to the NIR region, which exhibits complementary absorption profile to another organic dye FNE46 based on quinoxaline. When FNE46 and FNE53 are used as cosensitizers for metal-free cocktail-type quasi-solid-state DSSCs, sensitizer FNE53 not only extends the photoresponse range but also suppresses the intermolecular interactions among the dye molecules. Therefore, the cocktail-type quasi-solid-state DSSC displays much higher IPCE value compared with that for the DSSC sensitizer based on FNE53 and a broader IPCE response in comparison to that for the DSSC sensitizers based on FNE46, respectively. After the molar ratio between the two cocktail dyes is optimized, the highest energy conversion efficiency of 8.04% is achieved in a metal-free quasi-solid-state DSSC cosensitized with FNE46 and FNE53, which exhibits good long-term stability after continuous light soaking for 1000 h. PMID:25291482

Lu, Xuefeng; Lan, Tian; Qin, Zhenwen; Wang, Zhong-Sheng; Zhou, Gang

2014-11-12

192

Femtosecond to millisecond studies of electron transfer processes in a donor-(?-spacer)-acceptor series of organic dyes for solar cells interacting with titania nanoparticles and ordered nanotube array films.  

PubMed

Time-resolved emission and absorption spectroscopy are used to study the photoinduced dynamics of forward and back electron transfer processes taking place between a recently synthesized series of donor-(?-spacer)-acceptor organic dyes and semiconductor films. Results are obtained for vertically oriented titania nanotube arrays (inner diameters 36 nm and 70 nm), standard titania nanoparticles (25 nm diameter) and, as a reference, alumina nanoparticle (13 nm diameter) films. The studied dyes contain a triphenylamine group as an electron donor, cyanoacrylic acid part as an electron acceptor, and differ by the substituents in a spacer group that causes a shift of its absorption spectra. Despite a red-shift of the dye absorption band resulting in an improved response to the solar spectrum, smaller electron injection rates and smaller extinction coefficients result in reduced dye sensitized solar cell (DSSC) conversion efficiencies. For the most efficient dye, TPC1, electron injection from the hot locally excited state to titania on a time scale of about 100 fs is suggested, while from the relaxed charge transfer state it proceeds in a non-exponential way with time constants from 1 ps to 50 ps. Our results imply that the latter process involves the trap states below the conduction band edge (or the sub-bandgap tail of the acceptor states), localized close to the dye radical cation, and is accompanied by fast electron recombination to the parent dye's ground state. This process should limit the efficiency of DSSCs made using these types of organic dyes. The residual, slower recombination can be described by a stretched exponential decay with a characteristic time of 0.5 ?s and a dispersion parameter of 0.33. Both the electron injection and back electron transfer dynamics are similar in titania nanoparticles and nanotubes. Variations between the two film types are only found in the time resolved emission transients, which are explained in terms of the difference in local electric fields affecting the position of the emission bands. PMID:22258566

Zi?ek, Marcin; Cohen, Boiko; Yang, Xichuan; Sun, Licheng; Paulose, Maggie; Varghese, Oomman K; Grimes, Craig A; Douhal, Abderrazzak

2012-02-28

193

Simultaneous identification of natural dyes in the collection of drawings and maps from The Royal Chancellery Archives in Granada (Spain) by CE.  

PubMed

A simple and rapid capillary electrophoretic method with UV detection (CE-UV) has been developed for the identification of five natural dyes namely, carmine, indigo, saffron, gamboge and Rubia tinctoria root. The separation was performed in a fused-silica capillary of 64.5 cm length and 50 microm id. The running buffer was 40 mM sodium tetraborate buffer solution (pH 9.25). The applied potential was 30 kV, the temperature was 25 degrees C and detections were performed at 196, 232, 252, 300 and 356 nm. The injections were under pressure of 50 mbar during 13 s. The method was applied to the identification of carminic acid, gambogic acid, crocetin, indigotin, alizarin and purpurin in the collection of drawings and maps at the Royal Chancellery Archives in Granada (Spain). The method was validated by using HPLC as a reference method. PMID:17366480

Lpez-Montes, Ana; Blanc Garca, Rosario; Espejo, Teresa; Huertas-Perez, Jos F; Navaln, Alberto; Vlchez, Jos Luis

2007-04-01

194

Just Dyeing to Find Out.  

ERIC Educational Resources Information Center

Presents a multidisciplinary unit on natural dyes designed to take advantage of the natural curiosity of middle school students. Discusses history of dyes, natural dyes, preparation of dyes, and the dyeing process. (JRH)

Monhardt, Becky Meyer

1996-01-01

195

Evaluation of some fluorescent dyes for water tracing  

Microsoft Academic Search

Eight fluorescent dyes were compared in the laboratory and in field experiments to assess their utility in quantitative tracing work. The properties considered included sensitivity and minimum detectability, the effect of water chemistry on dye fluorescence, photochemical and biological decay rates, adsorption losses on equipment and sediments, toxicity to man and aquatic organisms, and cost. Orange dyes are more useful

P. L. Smart; I. M. S. Laidlaw

1977-01-01

196

Platinum-Free Counter Electrode Comprised of Metal-Organic-Framework (MOF)-Derived Cobalt Sulfide Nanoparticles for Efficient Dye-Sensitized Solar Cells (DSSCs)  

NASA Astrophysics Data System (ADS)

We fabricated a highly efficient (with a solar-to-electricity conversion efficiency (?) of 8.1%) Pt-free dye-sensitized solar cell (DSSC). The counter electrode was made of cobalt sulfide (CoS) nanoparticles synthesized via surfactant-assisted preparation of a metal organic framework, ZIF-67, with controllable particle sizes (50 to 320 nm) and subsequent oxidation and sulfide conversion. In contrast to conventional Pt counter electrodes, the synthesized CoS nanoparticles exhibited higher external surface areas and roughness factors, as evidenced by X-ray diffraction (XRD), scanning electron microscopy (SEM) element mapping, and electrochemical analysis. Incident photon-to-current conversion efficiency (IPCE) results showed an increase in the open circuit voltage (VOC) and a decrease in the short-circuit photocurrent density (Jsc) for CoS-based DSSCs compared to Pt-based DSSCs, resulting in a similar power conversion efficiency. The CoS-based DSSC fabricated in the study show great potential for economically friendly production of Pt-free DSSCs.

Hsu, Shao-Hui; Li, Chun-Ting; Chien, Heng-Ta; Salunkhe, Rahul R.; Suzuki, Norihiro; Yamauchi, Yusuke; Ho, Kuo-Chuan; Wu, Kevin C.-W.

2014-11-01

197

3D Hierarchical Rutile TiO2 and Metal-free Organic Sensitizer Producing Dye-sensitized Solar Cells 8.6% Conversion Efficiency  

NASA Astrophysics Data System (ADS)

Three-dimensional (3D) hierarchical nanoscale architectures comprised of building blocks, with specifically engineered morphologies, are expected to play important roles in the fabrication of `next generation' microelectronic and optoelectronic devices due to their high surface-to-volume ratio as well as opto-electronic properties. Herein, a series of well-defined 3D hierarchical rutile TiO2 architectures (HRT) were successfully prepared using a facile hydrothermal method without any surfactant or template, simply by changing the concentration of hydrochloric acid used in the synthesis. The production of these materials provides, to the best of our knowledge, the first identified example of a ledgewise growth mechanism in a rutile TiO2 structure. Also for the first time, a Dye-sensitized Solar Cell (DSC) combining a HRT is reported in conjunction with a high-extinction-coefficient metal-free organic sensitizer (D149), achieving a conversion efficiency of 5.5%, which is superior to ones employing P25 (4.5%), comparable to state-of-the-art commercial transparent titania anatase paste (5.8%). Further to this, an overall conversion efficiency 8.6% was achieved when HRT was used as the light scattering layer, a considerable improvement over the commercial transparent/reflector titania anatase paste (7.6%), a significantly smaller gap in performance than has been seen previously.

Lin, Jianjian; Heo, Yoon-Uk; Nattestad, Andrew; Sun, Ziqi; Wang, Lianzhou; Kim, Jung Ho; Dou, Shi Xue

2014-08-01

198

Platinum-free counter electrode comprised of metal-organic-framework (MOF)-derived cobalt sulfide nanoparticles for efficient dye-sensitized solar cells (DSSCs).  

PubMed

We fabricated a highly efficient (with a solar-to-electricity conversion efficiency (?) of 8.1%) Pt-free dye-sensitized solar cell (DSSC). The counter electrode was made of cobalt sulfide (CoS) nanoparticles synthesized via surfactant-assisted preparation of a metal organic framework, ZIF-67, with controllable particle sizes (50 to 320?nm) and subsequent oxidation and sulfide conversion. In contrast to conventional Pt counter electrodes, the synthesized CoS nanoparticles exhibited higher external surface areas and roughness factors, as evidenced by X-ray diffraction (XRD), scanning electron microscopy (SEM) element mapping, and electrochemical analysis. Incident photon-to-current conversion efficiency (IPCE) results showed an increase in the open circuit voltage (VOC) and a decrease in the short-circuit photocurrent density (Jsc) for CoS-based DSSCs compared to Pt-based DSSCs, resulting in a similar power conversion efficiency. The CoS-based DSSC fabricated in the study show great potential for economically friendly production of Pt-free DSSCs. PMID:25382139

Hsu, Shao-Hui; Li, Chun-Ting; Chien, Heng-Ta; Salunkhe, Rahul R; Suzuki, Norihiro; Yamauchi, Yusuke; Ho, Kuo-Chuan; Wu, Kevin C-W

2014-01-01

199

3D hierarchical rutile TiO2 and metal-free organic sensitizer producing dye-sensitized solar cells 8.6% conversion efficiency.  

PubMed

Three-dimensional (3D) hierarchical nanoscale architectures comprised of building blocks, with specifically engineered morphologies, are expected to play important roles in the fabrication of 'next generation' microelectronic and optoelectronic devices due to their high surface-to-volume ratio as well as opto-electronic properties. Herein, a series of well-defined 3D hierarchical rutile TiO2 architectures (HRT) were successfully prepared using a facile hydrothermal method without any surfactant or template, simply by changing the concentration of hydrochloric acid used in the synthesis. The production of these materials provides, to the best of our knowledge, the first identified example of a ledgewise growth mechanism in a rutile TiO2 structure. Also for the first time, a Dye-sensitized Solar Cell (DSC) combining a HRT is reported in conjunction with a high-extinction-coefficient metal-free organic sensitizer (D149), achieving a conversion efficiency of 5.5%, which is superior to ones employing P25 (4.5%), comparable to state-of-the-art commercial transparent titania anatase paste (5.8%). Further to this, an overall conversion efficiency 8.6% was achieved when HRT was used as the light scattering layer, a considerable improvement over the commercial transparent/reflector titania anatase paste (7.6%), a significantly smaller gap in performance than has been seen previously. PMID:25167837

Lin, Jianjian; Heo, Yoon-Uk; Nattestad, Andrew; Sun, Ziqi; Wang, Lianzhou; Kim, Jung Ho; Dou, Shi Xue

2014-01-01

200

Platinum-Free Counter Electrode Comprised of Metal-Organic-Framework (MOF)-Derived Cobalt Sulfide Nanoparticles for Efficient Dye-Sensitized Solar Cells (DSSCs)  

PubMed Central

We fabricated a highly efficient (with a solar-to-electricity conversion efficiency (?) of 8.1%) Pt-free dye-sensitized solar cell (DSSC). The counter electrode was made of cobalt sulfide (CoS) nanoparticles synthesized via surfactant-assisted preparation of a metal organic framework, ZIF-67, with controllable particle sizes (50 to 320?nm) and subsequent oxidation and sulfide conversion. In contrast to conventional Pt counter electrodes, the synthesized CoS nanoparticles exhibited higher external surface areas and roughness factors, as evidenced by X-ray diffraction (XRD), scanning electron microscopy (SEM) element mapping, and electrochemical analysis. Incident photon-to-current conversion efficiency (IPCE) results showed an increase in the open circuit voltage (VOC) and a decrease in the short-circuit photocurrent density (Jsc) for CoS-based DSSCs compared to Pt-based DSSCs, resulting in a similar power conversion efficiency. The CoS-based DSSC fabricated in the study show great potential for economically friendly production of Pt-free DSSCs. PMID:25382139

Hsu, Shao-Hui; Li, Chun-Ting; Chien, Heng-Ta; Salunkhe, Rahul R.; Suzuki, Norihiro; Yamauchi, Yusuke; Ho, Kuo-Chuan; Wu, Kevin C.-W.

2014-01-01

201

Application of surface-enhanced Raman scattering (SERS) for the identification of anthraquinone dyes used in works of art  

SciTech Connect

Surface-enhanced Raman scattering (SERS) was investigated for applications in the analysis of anthraquinone dyes used in works of art. Two SERS procedures were developed and evaluated with three frequently used anthraquinone dyes, alizarin, carminic acid and lac dye. The first procedure involves coating a layer of silver nanoparticles directly on pieces of filter paper stained with the dyes of interest by thermal evaporation to induce SERS effect. In the second procedure, a SERS-active Ag-Al{sub 2}O{sub 3} substrate was prepared by spin-coating an alumina-nanoparticle layer onto a glass slide to provide the nanostructure of the substrate, followed by thermally evaporating a layer of silver nanoparticles on top of the alumina layer. Aliquots of dye solutions were delivered onto this substrate to be analyzed. Intense SERS spectra characteristic of alizarin, carminic acid and lac dye were obtained using both SERS procedures. The effects of two parameters, the concentration of the alumina suspension and the thickness of the silver nanoparticle layer on the performance of the Ag-Al{sub 2}O{sub 3} substrate were examined with alizarin as the model compound. Comparative studies were conducted between the Ag-Al{sub 2}O{sub 3} substrate and the SERS substrate prepared using Tollens reaction. The Ag-Al{sub 2}O{sub 3} substrate was shown to offer larger enhancement and improved reproducibility than the Tollens substrates. Finally, the potential applicability of the Ag-Al{sub 2}O{sub 3} substrate for the analysis of real artifact objects was illustrated by the identification of alizarin extracted from a small piece of textile dyed using traditional methods and materials. The limit of detection for alizarin was estimated to be 7 x 10{sup -15} g from tests performed on solutions of known concentration.

Chen, Kui [ORNL; Leona, Marco [ORNL; Yan, Fei [ORNL; Wabuyele, Musundi B [ORNL; Vo Dinh, Tuan [ORNL

2006-04-01

202

Removal of acidic dye from aqueous solutions using poly(DMAEMAAMPSHEMA) terpolymer\\/MMT nanocomposite hydrogels  

Microsoft Academic Search

In this study, poly(DMAEMAAMPSHEMA) terpolymer\\/montmorillonite nanocomposite hydrogels were prepared by in situ polymerization\\u000a technique using 2-(N,N-dimethylamino)ethyl methacrylate (DMAEMA), 2-acrylamido-2-methlypropane sulfonic acid (AMPS), 2-hydroxyethyl methacrylate\\u000a (HEMA) monomers in clay suspension media. N,N-methylenebisacrylamide (NMBA) was used as crosslinker and potassium persulfate\\/potassium bisulfide were used as initiator\\u000a and accelerator pair. The water absorption capacities and acidic dye (indigo carmine) adsorption properties of the

Mert Dalaran; Serkan Emik; Gamze Gl; Tlin Banu ?yim; Saadet zgm?

2009-01-01

203

Suitability of Polymeric Media In Solid State Dye Lasers  

NASA Astrophysics Data System (ADS)

Solid hosts doped with organic dyes are suitable for tunable solid state lasers because of large band width in visible region. Moreover they also overcome the problems of toxicity and limited tunability due to liquid solutions of the dyes. We report fluorescence spectra of different rhodamine dyes in different solid hosts which can be quite helpful in choosing the proper solid host for solid state dye lasers.

Sharma, Amit; Saini, G. S. S.

2011-12-01

204

Huge suppression of charge recombination in P3HT-ZnO organic-inorganic hybrid solar cells by locating dyes at the ZnO/P3HT interfaces.  

PubMed

The charge separation and charge recombination dynamics in P3HT-ZnO and P3HT-dye-ZnO bulk heterojunction organic-inorganic hybrid solar cells (OIHSCs) prepared by a one-pot method were studied using a transient absorption (TA) method, both for optical absorption of P3HT in the visible region and for optical absorption of SQ36 in the NIR region. In the case of P3HT-ZnO, the charge separation was very fast, occurring within 1 ps. On the other hand, high charge recombination between electrons in the surface states and/or the conduction band of ZnO and holes in P3HT was observed. In the case of P3HT-dye-ZnO, we found that the charge recombination could be greatly suppressed by locating the dye at the P3HT/ZnO interfaces while maintaining a fast charge separation rate (a few ps to 10 ps). Our findings provide one methodology for the design of OIHSCs for improving their conversion efficiency, which is to position the dye at the appropriate BHJ interfaces. PMID:23877400

Shen, Qing; Ogomi, Yuhei; Das, Sandeep K; Pandey, Shyam S; Yoshino, Kenji; Katayama, Kenji; Momose, Hisayo; Toyoda, Taro; Hayase, Shuzi

2013-09-14

205

Comparison of dye doping and ultrathin emissive layer in white organic light-emitting devices with dual emissive layers  

NASA Astrophysics Data System (ADS)

White organic light-emitting devices (WOLEDs) with combined doping emissive layer (EML) and ultrathin EML have been fabricated to investigate the effect of each EML on the electroluminescent (EL) performance of the WOLEDs. Through tailoring doping concentration of bis[(4,6-difluorophenyl)-pyridinato-N,C2'](picolinate) iridium(III) (FIrpic) and thickness of ultrathin bis[2-(4-tertbutylphenyl)benzothiazolato-N,C2'] iridium (acetylacetonate) [(tbt)2Ir(acac)] EML, it is found that the change in the doping ratio of FIrpic significantly influenced the EL efficiencies and spectra, while the alteration of ultrathin EML thickness had much milder effect on the EL performance. The results indicated that ultrathin EML is in favor of reproducibility in mass production compared with doping method.

Wang, Xu; Qi, Yige; Yu, Junsheng

2014-09-01

206

Accurate simulation of optical properties in dyes.  

PubMed

Since Antiquity, humans have produced and commercialized dyes. To this day, extraction of natural dyes often requires lengthy and costly procedures. In the 19th century, global markets and new industrial products drove a significant effort to synthesize artificial dyes, characterized by low production costs, huge quantities, and new optical properties (colors). Dyes that encompass classes of molecules absorbing in the UV-visible part of the electromagnetic spectrum now have a wider range of applications, including coloring (textiles, food, paintings), energy production (photovoltaic cells, OLEDs), or pharmaceuticals (diagnostics, drugs). Parallel to the growth in dye applications, researchers have increased their efforts to design and synthesize new dyes to customize absorption and emission properties. In particular, dyes containing one or more metallic centers allow for the construction of fairly sophisticated systems capable of selectively reacting to light of a given wavelength and behaving as molecular devices (photochemical molecular devices, PMDs).Theoretical tools able to predict and interpret the excited-state properties of organic and inorganic dyes allow for an efficient screening of photochemical centers. In this Account, we report recent developments defining a quantitative ab initio protocol (based on time-dependent density functional theory) for modeling dye spectral properties. In particular, we discuss the importance of several parameters, such as the methods used for electronic structure calculations, solvent effects, and statistical treatments. In addition, we illustrate the performance of such simulation tools through case studies. We also comment on current weak points of these methods and ways to improve them. PMID:19113946

Jacquemin, Denis; Perpte, Eric A; Ciofini, Ilaria; Adamo, Carlo

2009-02-17

207

Pickering emulsions prepared by layered niobate K?Nb?O?? intercalated with organic cations and photocatalytic dye decomposition in the emulsions.  

PubMed

We investigated emulsions stabilized with particles of layered hexaniobate, known as a semiconductor photocatalyst, and photocatalytic degradation of dyes in the emulsions. Hydrophobicity of the niobate particles was adjusted with the intercalation of alkylammonium ions into the interlayer spaces to enable emulsification in a toluene-water system. After the modification of interlayer space with hexylammonium ions, the niobate stabilized water-in-oil (w/o) emulsions in a broad composition range. Optical microscopy showed that the niobate particles covered the surfaces of emulsion droplets and played a role of emulsifying agents. The niobate particles also enabled the generation of oil-in-water (o/w) emulsions in a limited composition range. Modification with dodecylammonium ions, which turned the niobate particles more hydrophobic, only gave w/o emulsions, and the particles were located not only at the toluene-water interface but also inside the toluene continuous phase. On the other hand, interlayer modification with butylammonium ions led to the formation of o/w emulsions. When porphyrin dyes were added to the system, the cationic dye was adsorbed on niobate particles at the emulsion droplets whereas the lipophilic dye was dissolved in toluene. Upon UV irradiation, both of the dyes were degraded photocatalytically. When the cationic and lipophilic porphyrin molecules were simultaneously added to the emulsions, both of the dyes were photodecomposed nonselectively. PMID:22850398

Nakato, Teruyuki; Ueda, Hiroaki; Hashimoto, Sachika; Terao, Ryosuke; Kameyama, Miyuki; Mouri, Emiko

2012-08-01

208

Textile dye dermatitis.  

PubMed

The literature concerning textile dye dermatitis published during the last decade was reviewed. Sixty-one cases of dye-allergic contact dermatitis in which the presentation or course of the dermatitis was unusual or the dye allergen was one not previously reported have been described. The four new dye allergens discovered were Disperse Blue 106, Disperse Blue 85, Disperse Brown 1, and Basic Red 46. The incidence of dye dermatitis varied from 1% to 15.9% depending on the country, patient sample, and number of dyes in the patch test series. The 10 new dye allergens discovered in these studies were Disperse Blue 153, Disperse Orange 13, Basic Black 1, Basic Brown 1, the acid dyes Supramine Yellow and Supramine Red, the direct dye Diazol Orange, the basic dye Brilliant Green, Turquoise Reactive, and Neutrichrome Red. Disperse Blue 106 and Disperse Blue 124 were shown to be the strongest clothing dye sensitizers to date. Standard screening patch test series were found to be inadequate for the detection of textile dye sensitivity; therefore textile dye patch test series should be used. It is difficult to determine whether the incidence of dye dermatitis is increasing or decreasing because controlled epidemiologic studies are lacking, but data suggest that textile dye sensitivity is more common than previously believed. PMID:7896955

Hatch, K L; Maibach, H I

1995-04-01

209

Structure of cationic dyes assemblies intercalated in the films of montmorillonite  

Microsoft Academic Search

Hybrid materials based on cationic organic dyes intercalated in oriented clay mineral films were prepared via dye adsorption from aqueous solutions on the films having been prepared by a spin-coating method. The films with four thiazine dyes thionine, azure A, azure B and methylene blue and one representative xanthene dye, pyronin Y (Py), were investigated. Four reduced charge montmorillonites (RCM)

Juraj Bujdk; Adriana Czmerov; Nobuo Iyi

2008-01-01

210

Covalently dye-linked, surface-controlled, and bioconjugated organically modified silica nanoparticles as targeted probes for optical imaging.  

PubMed

In this paper we report the synthesis and characterization of organically modified silica (ORMOSIL) nanoparticles, covalently incorporating the fluorophore rhodamine-B, and surface-functionalized with a variety of active groups. The synthesized nanoparticles are of ultralow size (diameter approximately 20 nm), highly monodispersed, stable in aqueous suspension, and retain the optical properties of the incorporated fluorophore. The surface of the nanoparticles can be functionalized with a variety of active groups such as hydroxyl, thiol, amine, and carboxyl. The carboxyl groups on the surface were used to conjugate with various bioactive molecules such as transferrin, as well as monoclonal antibodies such as anti-claudin 4 and anti-mesothelin, for targeted delivery to pancreatic cancer cell lines. In vitro experiments have revealed that the cellular uptake of these bioconjugated (targeted) nanoparticles is significantly higher than that of the nonconjugated ones. The ease of surface functionalization and incorporation of a variety of biotargeting molecules, combined with their observed noncytotoxicity, makes these fluorescent ORMOSIL nanoparticles potential candidates as efficient probes for optical bioimaging, both in vitro and in vivo. PMID:19206569

Kumar, Rajiv; Roy, Indrajit; Ohulchanskyy, Tymish Y; Goswami, Lalit N; Bonoiu, Adela C; Bergey, Earl J; Tramposch, Kenneth M; Maitra, Anirban; Prasad, Paras N

2008-03-01

211

Chalcogenopyrylium Dyes as Differential Modulators of Organic Anion Transport by Multidrug Resistance Protein 1 (MRP1), MRP2, and MRP4  

PubMed Central

Multidrug resistance proteins (MRPs) mediate the ATP-dependent efflux of structurally diverse compounds, including anticancer drugs and physiologic organic anions. Five classes of chalcogenopyrylium dyes (CGPs) were examined for their ability to modulate transport of [3H]estradiol glucuronide (E217?G; a prototypical MRP substrate) into MRP-enriched inside-out membrane vesicles. Additionally, some CGPs were tested in intact transfected cells using a calcein efflux assay. Sixteen of 34 CGPs inhibited MRP1-mediated E217?G uptake by >50% (IC50 values: 0.77.6 M). Of 9 CGPs with IC50 values ?2 M, two belonged to class I, two to class III, and five to class V. When tested in the intact cells, only 4 of 16 CGPs (at 10 M) inhibited MRP1-mediated calcein efflux by >50% (III-1, V-3, V-4, V-6), whereas a fifth (I-5) inhibited efflux by just 23%. These five CGPs also inhibited [3H]E217?G uptake by MRP4. In contrast, their effects on MRP2 varied, with two (V-4, V-6) inhibiting E217?G transport (IC50 values: 2.0 and 9.2 M) and two (V-3, III-1) stimulating transport (>2-fold), whereas CGP I-5 had no effect. Strikingly, although V-3 and V-4 had opposite effects on MRP2 activity, they are structurally identical except for their chalcogen atom (Se versus Te). This study is the first to identify class V CGPs, with their distinctive methine or trimethine linkage between two disubstituted pyrylium moieties, as a particularly potent class of MRP modulators, and to show that, within this core structure, differences in the electronegativity associated with a chalcogen atom can be the sole determinant of whether a compound will stimulate or inhibit MRP2. PMID:23530018

Myette, Robert L.; Conseil, Gwenalle; Ebert, Sean P.; Wetzel, Bryan; Detty, Michael R.

2013-01-01

212

Sensitively monitoring photodegradation process of organic dye molecules by surface-enhanced Raman spectroscopy based on Fe3O4@SiO2@TiO2@Ag particle.  

PubMed

Photodegradation of organic dye molecules has attracted extensive attention because of their high toxicity to water resources. Compared with traditional UV-visible spectroscopy, SERS technology can reflect more sensitively the catalytic degradation process occurring on the surface of the catalysts. In this paper, we report the synthesis and structure of Fe3O4@SiO2@TiO2@Ag composite, which integrates SERS active Ag nanostructure with catalytically active titania. The degradation of the typical dye molecule crystal violet (CV), as an example, is investigated in the presence of the as-prepared Fe3O4@SiO2@TiO2@Ag composite structure, which exhibits high catalytic activity and good SERS performance. At the same time, renewable photocatalytic activity was also investigated. PMID:25192200

Qin, Suhua; Cai, Wenya; Tang, Xianghu; Yang, Liangbao

2014-11-01

213

The Development and Application of Novel IR and NMR-Based Model for the Evaluation of Carminative Effect of Artemisia judaica L. Essential Oil  

PubMed Central

Artemisia judaica L. is a medicinal plant that is traditionally used to relieve abdominal pains through its carminative activity. In this study, spectroscopic analysis was employed to investigate the carminative activity associated with A. judaica. Using infrared spectroscopy, the carminative activity was evaluated based on the first derivative of IR-characteristic stretching signal of CO2. Our results indicate that A. judaica oil effectively reduced the response of CO2 signal equivalent to thymol standard. Additionally, 1H-NMR spectroscopy was utilized to assess surface activity of A. judaica crude oil through the reduction of interfacial tension in a D2O/CDCl3 system. Apparently, 10?mg of the oil was able to solubilize water in a chloroform layer up to 4.3% (w/w). In order to correlate the observed surface activity of the oil to its actual composition, GC-MS and GC-FID structural analysis were undertaken. The results revealed that the oil composition consists of oxygenated terpenes which might be responsible for the carminative effect. Furthermore, owing to its sensitivity, our model provides a fundamental basis for the pharmacological assessment of trace amounts of oils with high precision and accuracy. PMID:25614741

Alzweiri, Muhammed; Alrawashdeh, Ibrahim M.; Bardaweel, Sanaa K.

2014-01-01

214

Method of dye removal for the textile industry  

DOEpatents

The invention comprises a method of processing a waste stream containing dyes, such as a dye bath used in the textile industry. The invention comprises using an inorganic-based polymer, such as polyphosphazene, to separate dyes and/or other chemicals from the waste stream. Membranes comprising polyphosphazene have the chemical and thermal stability to survive the harsh, high temperature environment of dye waste streams, and have been shown to completely separate dyes from the waste stream. Several polyphosplhazene membranes having a variety of organic substituent have been shown effective in removing color from waste streams.

Stone, Mark L. (Idaho Falls, ID)

2000-01-01

215

Method of dye removal for the textile industry  

SciTech Connect

The invention comprises a method of processing a waste stream containing dyes, such as a dye bath used in the textile industry. The invention uses an inorganic-based polymer, such as polyphosphazene, to separate dyes and/or other chemicals from the waste stream. Membranes comprising polyphosphazene have the chemical and thermal stability to survive the harsh, high temperature environment of dye waste streams, and have been shown to completely separate dyes from the waste stream. Several polyphosplhazene membranes having a variety of organic substituent have been shown effective in removing color from waste streams.

Stone, M.L.

2000-07-25

216

Anthracene/Phenothiazine ?-Conjugated Sensitizers for Dye-Sensitized Solar Cells using Redox Mediator in Organic and Water-based Solvents.  

PubMed

Metal-free dyes (MD1 to MD5) containing an anthracene/phenothiazine unit in the spacer have been synthesized. The conversion efficiency (7.13?%) of the dye-sensitized solar cell using MD3 as the sensitizer reached approximately 85?% of the N719-based standard cell (8.47?%). The cell efficiency (8.42?%) of MD3-based dye-sensitized solar cells (DSSCs) with addition of chenodeoxycholic acid is comparable with that of N719-based standard cell. The MD3 water-based DSSCs using a dual-TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl)/iodide electrolyte exhibited very promising cell performance of 4.96?% with an excellent Voc of 0.77?V. PMID:25404282

Lin, Ryan Yeh-Yung; Chuang, Tzu-Man; Wu, Feng-Ling; Chen, Pei-Yu; Chu, Te-Chun; Ni, Jen-Shyang; Fan, Miao-Syuan; Lo, Yih-Hsing; Ho, Kuo-Chuan; Lin, Jiann T

2015-01-01

217

Role of rare earth oxide nanoparticles (CeO2 and La2O3) in suppressing the photobleaching of fluorescent organic dyes.  

PubMed

Aqueous solutions with Rhodamine dye, and fluorescently labeled polymer samples of fibrin and collagen were mixed with aqueous dispersions of cerium oxide, lanthanum oxide, iron (II) oxide nanoparticles, and OxyFluor, a commonly used reagent for suppressing photobleaching. From time dependent studies of the fluorescence from these samples, we observed that the dyes in samples containing rare earth oxide nanoparticles exhibited significantly slower rates of fluorescence decay compared to control samples without additives, or containing OxyFluor or iron oxide nanoparticles. We posit that this may be related to the oxygen free radical scavenging properties of rare earth oxides. PMID:24706286

Guha, Anubhav; Basu, Anindita

2014-05-01

218

Electron transfer mediation by aqueous C60 aggregates in H2O2/UV advanced oxidation of indigo carmine  

NASA Astrophysics Data System (ADS)

C60 fullerene has long been known to exhibit favorable electron accepting and shuttling properties, but little is known about the possibility of electron transfer mediation by fullerene aggregates (nC60) in water. In this study, we investigated the electron shuttling capabilities of nC60 using UV/H2O2 as a model oxidation process in the presence of an electron donor, indigo carmine (IC). nC60 addition to the IC/H2O2 system was found to drastically increase IC degradation and shift the reactive oxygen species (ROS) balance, favoring the formation of superoxide and perhydroxyl radical species compared to hydroxyl radicals. Results indicate that nC60 can act as an electron mediator, where the adsorbed IC donates an electron to nC60, which is subsequently transferred to H2O2 or perhydroxyl radical.C60 fullerene has long been known to exhibit favorable electron accepting and shuttling properties, but little is known about the possibility of electron transfer mediation by fullerene aggregates (nC60) in water. In this study, we investigated the electron shuttling capabilities of nC60 using UV/H2O2 as a model oxidation process in the presence of an electron donor, indigo carmine (IC). nC60 addition to the IC/H2O2 system was found to drastically increase IC degradation and shift the reactive oxygen species (ROS) balance, favoring the formation of superoxide and perhydroxyl radical species compared to hydroxyl radicals. Results indicate that nC60 can act as an electron mediator, where the adsorbed IC donates an electron to nC60, which is subsequently transferred to H2O2 or perhydroxyl radical. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr03647f

Ge, Ling; Moor, Kyle; Zhang, Bo; He, Yiliang; Kim, Jae-Hong

2014-10-01

219

Optofluidic dye lasers  

Microsoft Academic Search

Optofluidic dye lasers are microfabricated liquid dye lasers enabled by the microfluidics technology. The integration of dye\\u000a lasers with microfluidics not only facilitates the implementation of complete lab-on-a-chip systems, but also allows the\\u000a dynamical control of the laser properties which is not achievable with solid-state optical components. We review the recent\\u000a demonstrations of on-chip liquid dye lasers and some of

Zhenyu Li; Demetri Psaltis

2008-01-01

220

Dye Like A Natural  

NSDL National Science Digital Library

In this activity, learners stain fabrics--on purpose! Learners explore the art of natural dyeing by using dyes and substrates that are both derived from plant or animal sources as well as mordant solutions. Learners compare the color and effectiveness of different mordant/dye combinations on the different substrates.

Yu, Julie

2010-01-01

221

Identification of anthraquinone coloring matters in natural red dyes by electrospray mass spectrometry coupled to capillary electrophoresis.  

PubMed

Capillary electrophoresis with UV/visible diode-array detection (DAD) and electrospray mass spectrometric (ESI-MS) detection were used for the identification of anthraquinone color components of cochineal, lac-dye and madder, natural red dyestuffs often used by ancient painters. For the purpose of such analysis, ESI-MS was found to be a much more appropriate detection technique than DAD one owing to its higher sensitivity (detection limits in the range 0.1-0.5 micro g ml(-1)) and selectivity. The method developed made it possible to identify unequivocally carminic acid and laccaic acids A, B and E as coloring matters in the examined preparations of cochineal and lac-dye, respectively. In madder, European Rubia tinctorum, alizarin and purpurin were found. The method allows the rapid, direct and straightforward identification and quantification of components of natural products used in art and could be very helpful in restoration and conservation procedures. PMID:14696204

Puchalska, Maria; Orli?ska, Magdalena; Ackacha, Mohamed A; Po?e?-Pawlak, Kasia; Jarosz, Maciej

2003-12-01

222

Anthraquinone dyes decolorization capacity of anamorphic Bjerkandera adusta CCBAS 930 strain and its HRP-like negative mutants.  

PubMed

Cultures of the anamorphic fungus Bjerkandera adusta CCBAS 930 decolorizing, in stationary cultures, 0.01% solutions of carminic acid and Poly R-478, were characterised by a strong increase in the activity of the horseradish peroxidase (HRP-like) and manganese-dependent peroxidase (MnP) at a low activity of lignin peroxidase. Genotypically modified mutants of B. adusta CCBAS 930: 930-5 and 930-14, with total or partial loss of decolorization capabilities relative to anthraquinonic dyes, showed inhibition of the activity of HRP-like peroxidase and MnP. Whereas, compared to the parental strain, in the mutant cultures there was an increase in the activity of lignin peroxidase and laccase. The paper presents a discussion of the role of the studied enzymatic activities in the process of decolorization of anthraquinonic dyes by the strain B. adusta CCBAS 930. PMID:24415463

Korni??owicz-Kowalska, Teresa; Rybczy?ska, Kamila

2014-06-01

223

Preparation of Nanoporous TiO2 for Dye-Sensitized Solar Cell (DSSC) Using Various Dyes  

NASA Astrophysics Data System (ADS)

This article reports the development of organic dyes as an attempt to reduce material costs of Dye-Sensitized Solar Cell (DSSC). Indonesia, a country with variety and considerable number of botanical resources, is suitable to perform the research. Indonesian black rice, curcuma, papaya leaf, and the combination were chosen as organic dyes source. Dyes were extracted using organic solvent and adsorbed on mesoporous Titanium Dioxide (TiO2) which has been optimized in our laboratory. The best dyes light absorbance and performance obtained from papaya leaf as chlorophyll dyes that gives two peaks at 432 nm and 664 nm from UV-Vis Spectrophotometry and performance under 100 mW/cm2 Xenon light solar simulator gives VOC = 0.566 Volt, JSC = 0.24 mA/cm2, Fill Factor = 0.33, and efficiency of energy conversion 0,045%.

Yuliarto, Brian; Fanani, Fahiem; Fuadi, M. Kasyful; Nugraha

2010-10-01

224

Synthesis of azoimidazolium dyes with nitrous oxide.  

PubMed

A new method for the synthesis of industrially important azoimidazolium dyes is presented. The procedure is based on a reagent which is rarely used in the context of synthetic organic chemistry: nitrous oxide ("laughing gas"). N2 O is first coupled to N-heterocyclic carbenes. Subsequent reaction with aromatic compounds through an AlCl3 -induced C?H activation process provides azoimidazolium dyes in good yields. PMID:25420599

Tskhovrebov, Alexander G; Naested, Lara C E; Solari, Euro; Scopelliti, Rosario; Severin, Kay

2015-01-19

225

Seeking effective dyes for a mediated glucose-air alkaline battery/fuel cell  

NASA Astrophysics Data System (ADS)

A significant level of power generation from an abiotic, air breathing, mediated reducing sugar-air alkaline battery/fuel cell has been achieved in our laboratories at room temperature without complicated catalysis or membrane separation in the reaction chamber. Our prior studies suggested that mass transport limitation by the mediator is a limiting factor in power generation. New and effective mediators were sought here to improve charge transfer and power density. Forty-five redox dyes were studied to identify if any can facilitate mass transport in alkaline electrolyte solution; namely, by increasing the solubility and mobility of the dye, and the valence charge carried per molecule. Indigo dyes were studied more closely to understand the complexity involved in mass transport. The viability of water-miscible co-solvents was also explored to understand their effect on solubility and mass transport of the dyes. Using a 2.0 mL solution, 20% methanol by volume, with 100 mM indigo carmine, 1.0 M glucose and 2.5 M sodium hydroxide, the glucose-air alkaline battery/fuel cell attained 8 mA cm-2 at short-circuit and 800 ?W cm-2 at the maximum power point. This work shall aid future optimization of mediated charge transfer mechanism in batteries or fuel cells.

Eustis, Ross; Tsang, Tsz Ming; Yang, Brigham; Scott, Daniel; Liaw, Bor Yann

2014-02-01

226

NIR Dyes for Bioimaging Applications  

PubMed Central

Summary of recent advances Fluorescent dyes based on small organic molecules that function in the near infra red (NIR) region are of great current interest in chemical biology. They allow for imaging with minimal autofluorescence from biological samples, reduced light scattering and high tissue penetration. Herein, examples of ongoing NIR fluorophore design strategies as well as their properties and anticipated applications relevant to the bioimaging are presented. PMID:19926332

Escobedo, Jorge O.; Rusin, Oleksandr; Lim, Soojin

2009-01-01

227

Two photon absorption energy transfer in the light-harvesting complex of photosystem II (LHC-II) modified with organic boron dye  

NASA Astrophysics Data System (ADS)

The plant light-harvesting complexes of photosystem II (LHC-II) play important roles in collecting solar energy and transferring the energy to the reaction centers of photosystems I and II. A two photon absorption compound, 4-(bromomethyl)-N-(4-(dimesitylboryl)phenyl)-N-phenylaniline (DMDP-CH2Br), was synthesized and covalently linked to the LHC-II in formation of a LHC-II-dye complex, which still maintained the biological activity of LHC-II system. Under irradiation with femtosecond laser pulses at 754 nm, the LHC-II-dye complex can absorb two photons of the laser light effectively compared with the wild type LHC-II. The absorbed excitation energy is then transferred to chlorophyll a with an obvious fluorescence enhancement. The results may be interesting and give potentials for developing hybrid photosystems.

Chen, Li; Liu, Cheng; Hu, Rui; Feng, Jiao; Wang, Shuangqing; Li, Shayu; Yang, Chunhong; Yang, Guoqiang

2014-07-01

228

Data mining with molecular design rules identifies new class of dyes for dye-sensitised solar cells.  

PubMed

A major deficit in suitable dyes is stifling progress in the dye-sensitised solar cell (DSC) industry. Materials discovery strategies have afforded numerous new dyes; yet, corresponding solution-based DSC device performance has little improved upon 11% efficiency, achieved using the N719 dye over two decades ago. Research on these dyes has nevertheless revealed relationships between the molecular structure of dyes and their associated DSC efficiency. Here, such structure-property relationships have been codified in the form of molecular dye design rules, which have been judiciously sequenced in an algorithm to enable large-scale data mining of dye structures with optimal DSC performance. This affords, for the first time, a DSC-specific dye-discovery strategy that predicts new classes of dyes from surveying a representative set of chemical space. A lead material from these predictions is experimentally validated, showing DSC efficiency that is comparable to many well-known organic dyes. This demonstrates the power of this approach. PMID:25011389

Cole, Jacqueline M; Low, Kian Sing; Ozoe, Hiroaki; Stathi, Panagiota; Kitamura, Chitoshi; Kurata, Hiroyuki; Rudolf, Petra; Kawase, Takeshi

2014-11-19

229

Resistance status of the carmine spider mite, Tetranychus cinnabarinus and the twospotted spider mite, T. urticae to selected acaricides on strawberries.  

PubMed

The carmine spider mite, Tetranychus cinnabarinus (Boisduval) and the twospotted spider mite, T. urticae Koch, are serious pests of strawberries and many other horticultural crops. Control of these pests has been heavily dependent upon chemical acaricides. Objectives of this study were to determine the resistance status of these two pest species to commonly used acaricides on strawberries in a year-round intensive horticultural production region. LC90 of abamectin for adult carmine spider mites was 4% whereas that for adult twospotted spider mites was 24% of the top label rate. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 0.5%, 0.5%, 1.4% and 83% of their respective highest label rates for carmine spider mite eggs, 0.7%, 2.7%, 12.1% and 347% of their respective highest label rates for the nymphs. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 4.6%, 11.1%, 310% and 62% of their respective highest label rates for twospotted spider mite eggs, 3%, 13%, 432,214% and 15% of their respective highest label rates for the nymphs. Our results suggest that T. cinnabarinus have developed resistance to bifenazate and that the T. urticae have developed resistance to hexythiazox. These results strongly emphasize the need to develop resistance management strategies in the region. This article is protected by copyright. All rights reserved. PMID:25409919

Bi, Jian-Long; Niu, Zi-Mian; Yu, Lu; Toscano, Nick C

2014-11-20

230

Zeolite-dye micro lasers  

E-print Network

We present a new class of micro lasers based on nanoporous molecular sieve host-guest systems. Organic dye guest molecules of 1-Ethyl-4-(4-(p-Dimethylaminophenyl)-1,3-butadienyl)-pyridinium Perchlorat were inserted into the 0.73-nm-wide channel pores of a zeolite AlPO$_4$-5 host. The zeolitic micro crystal compounds where hydrothermally synthesized according to a particular host-guest chemical process. The dye molecules are found not only to be aligned along the host channel axis, but to be oriented as well. Single mode laser emission at 687 nm was obtained from a whispering gallery mode oscillating in a 8-$\\mu$m-diameter monolithic micro resonator, in which the field is confined by total internal reflection at the natural hexagonal boundaries inside the zeolitic microcrystals.

Vietze, U; Laeri, F; Ihlein, G; Schth, F; Limburg, B; Abraham, M

1998-01-01

231

[Anaphylaxis to blue dyes].  

PubMed

In medicine, vital blue dyes are mainly used for the evaluation of sentinel lymph nodes in oncologic surgery. Perioperative anaphylaxis to blue dyes is a rare but significant complication. Allergic reactions to blue dyes are supposedly IgE-mediated and mainly caused by triarylmethanes (patent blue and isosulfane blue) and less frequently by methylene blue. These substances usually do not feature on the anesthesia record and should not be omitted from the list of suspects having caused the perioperative reaction, in the same manner as latex and chlorhexidine. The diagnosis of hypersensitivity to vital blue dyes can be established by skin test. We illustrate this topic with three clinical cases. PMID:24834647

Langner-Viviani, F; Chappuis, S; Bergmann, M M; Ribi, C

2014-04-16

232

Hair Dye and Hair Relaxers  

MedlinePLUS

... Bad Reaction to Cosmetics? Tell FDA Cosmetics Tips Hair Dye and Hair Relaxers En Espaol Hair dye is used to ... products. If you have a bad reaction to hair dyes and relaxers, you should: Stop using the ...

233

Influence of exposure to imidacloprid on survivorship, reproduction and vitellin content of the carmine spider mite, Tetranychus cinnabarinus.  

PubMed

Occasional reports linking neonicotinoid insecticide applications to field population outbreaks of the spider mite have been a topic of concern for integrated pest management programs. To elucidate the impacts of a neonicotinoid insecticide on the carmine spider mite, Tetranychus cinnabarinus Boisduval (Acari: Tetranychidae), the survivorship, reproduction, and vitellin contents of the mite were investigated after exposure to various concentrations of imidacloprid on the V. unguiculata leaf discs at 25 degrees C, 80% RH and a photoperiod of 14:10 (L:D) in the laboratory. The results showed that the field-relevant dose of imidacloprid did not significantly affect the hatch rate of eggs or pre-imaginal survivorship of the mite, while sublethal doses of imidacloprid, previously determined for Myzus persicae, led to a significant increase in the hatch rate of eggs and pre-imaginal survivorship of the mite compared to the untreated control. Adult longevity and fecundity of T. cinnabarinus for imidacloprid-treated populations were slightly prolonged and increased, respectively, but the difference from the untreated control was not significant. The vitellin content in eggs increased significantly after exposure to imidacloprid. Imidacloprid may be one of the major reasons for the outbreak of T. cinnabarinus in the field. PMID:20578884

Zeng, Chun-Xiang; Wang, Jin-Jun

2010-01-01

234

Rational design of hyperbranched 3D heteroarrays of SrS/CdS: synthesis, characterization and evaluation of photocatalytic properties for efficient hydrogen generation and organic dye degradation  

NASA Astrophysics Data System (ADS)

Hyperbranched 3D SrS/CdS nanostructures were synthesized using a one pot hydrothermal method. Transmission Electron Microscopy (TEM) and Field Emission-Scanning Electron Microscopy (FE-SEM) analysis showed the formation of flower-like structure and the crystalline phase was confirmed by powder X-ray diffraction. The prepared 3D SrS/CdS exhibited improved photocatalytic activity for water splitting leading to H2 generation (AQY 10%) and nearly complete degradation of methyl orange (MO) dye. The dye degradation followed first order kinetics and the apparent reaction rate constant (kapp) was 0.136 min-1. The present 3D SrS/CdS structure promise to be efficient photocatalysts due to (i) the facile intersystem charge transfer resulting from their band alignment (ii) enhanced specific surface area and (iii) crystallinity.Hyperbranched 3D SrS/CdS nanostructures were synthesized using a one pot hydrothermal method. Transmission Electron Microscopy (TEM) and Field Emission-Scanning Electron Microscopy (FE-SEM) analysis showed the formation of flower-like structure and the crystalline phase was confirmed by powder X-ray diffraction. The prepared 3D SrS/CdS exhibited improved photocatalytic activity for water splitting leading to H2 generation (AQY 10%) and nearly complete degradation of methyl orange (MO) dye. The dye degradation followed first order kinetics and the apparent reaction rate constant (kapp) was 0.136 min-1. The present 3D SrS/CdS structure promise to be efficient photocatalysts due to (i) the facile intersystem charge transfer resulting from their band alignment (ii) enhanced specific surface area and (iii) crystallinity. Electronic supplementary information (ESI) available: Schematic experimental setup for photocatalytic hydrogen generation, TEM of CdS NWs and SrS NPs, FESEM images of 3D SrS/CdS, Low resolution TEM images for 3D SrS/CdS, EDX and SAED, SEM of SrS/CdS at different ratios, progress of hydrogen production at different time interval, different UV-Vis absorption spectra of MO. See DOI: 10.1039/c2nr30666b

Khan, Ziyauddin; Chetia, Tridip Ranjan; Qureshi, Mohammad

2012-05-01

235

Radiation induced degradation of dyesAn overview  

Microsoft Academic Search

Synthetic dyes are a major part of our life. Products ranging from clothes to leather accessories to furniture all depend on extensive use of organic dyes. An unfortunate side effect of extensive use of these chemicals is that huge amounts of these potentially carcinogenic compounds enter our water supplies. Various advanced oxidation processes (AOPs) including the use of high-energy radiation

M. A. Rauf; S. Salman Ashraf

2009-01-01

236

Toxicity of Xanthene Food Dyes by Inhibition of Human Drug-Metabolizing Enzymes in a Noncompetitive Manner  

PubMed Central

The synthetic food dyes studied were rose bengal (RB), phroxine (PL), amaranth, erythrosine B (ET), allura red, new coccine, acid red (AR), tartrazine, sunset yellow FCF, brilliant blue FCF, and indigo carmine. First, data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. ET inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). We showed the inhibitory effect of xanthene dye on human UGT1A6 activity. Basic ET, PL, and RB in those food dyes strongly inhibited UGT1A6 activity, with IC50 values = 0.05, 0.04, and 0.015 mM, respectively. Meanwhile, AR of an acidic xanthene food dye showed no inhibition. Next, we studied the inhibition of CYP3A4 of a major phase I drug-metabolizing enzyme and P-glycoprotein of a major transporter by synthetic food dyes. Human CYP3A4 and P-glycoprotein were also inhibited by basic xanthene food dyes. The IC50 values of these dyes to inhibit CYP3A4 and P-glycoprotein were the same as the inhibition level of UGT1A6 by three halogenated xanthene food dyes (ET, PL, and RB) described above, except AR, like the results with UGT1A6 and UGT2B7. We also confirmed the noninhibition of CYP3A4 and P-gp by other synthetic food dyes. Part of this inhibition depended upon the reaction of 1O2 originating on xanthene dyes by light irradiation, because inhibition was prevented by 1O2 quenchers. We studied the influence of superoxide dismutase and catalase on this inhibition by dyes and we found prevention of inhibition by superoxide dismutase but not catalase. This result suggests that superoxide anions, originating on dyes by light irradiation, must attack drug-metabolizing enzymes. It is possible that red cosmetics containing phloxine, erythrosine, or rose bengal react with proteins on skin under lighting and may lead to rough skin. PMID:20041016

Mizutani, Takaharu

2009-01-01

237

Upconverting Organic Dye Doped Core-Shell Nano-Composites for Dual-Modality NIR Imaging and Photo-Thermal Therapy  

PubMed Central

Nanotechnology approaches offer the potential for creating new optical imaging agents with unique properties that enable uses such as combined molecular imaging and photo-thermal therapy. Ideal preparations should fluoresce in the near-infrared (NIR) region to ensure maximal tissue penetration depth along with minimal scattering and light absorption. Due to their unique photophysical properties, upconverting ceramics such as NaYF4:Er3+,Yb3+ nanoparticles have become promising optical materials for biological imaging. In this work, the design and synthesis of NaYF4:Er3+,Yb3+@SiO2 core-shell nano-composites, which contain highly absorbing NIR carbocyanine dyes in their outer silica shell, are described. These materials combine optical emission (from the upconverting core nanoparticle) with strong NIR absorption (from the carbocyanine dyes incorporated into the shell) to enable both optical imaging and photo-thermal treatment, respectively. Ultimately, this hybrid composite nanomaterial approach imparts the ability to both visualize, via upconversion imaging, and treat, via photo-thermal heating, using two distinct optical channels. Proof-of-principle in vitro experiments are presented to demonstrate the combined imaging and photo-thermal properties of this new functional nano-composite. PMID:23606913

Shan, Guobin; Weissleder, Ralph; Hilderbrand, Scott A.

2013-01-01

238

Oxazine laser dyes  

DOEpatents

New oxazine compounds useful as dye laser media in solution, are superiior to prior art materials. The oxazine dyes useful when pumped by the 578.2 nm copper line to operate in the 700-800 nm range are described by formula I ##STR1##

Hammond, Peter R. (Livermore, CA); Field, George F. (Danville, CA)

1992-01-01

239

Molecular design of the diketopyrrolopyrrole-based dyes with varied donor units for efficient dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

Three types of novel diketopyrrolopyrrole-based organic dyes (Type 1-3) with phenyl unit as an additional ?-bridge and triphenylamine or phenothiazine as the donors are designed and synthesized for dye-sensitized solar cells (DSSCs). Type 1 dyes incorporating the donor segment directly to the diketopyrrolopyrrole core lead to a better electron communication between the donor and acceptor, allowing an efficient charge transfer process. Type 2 and Type 3 dyes with a phenyl unit between the donor and diketopyrrolopyrrole unit show lower delocalization of the excited state. Compared with Type 3 dyes, Type 1 dyes exhibit higher conjugated skeleton co planarity and shorter electron transfer distance from the donor to TiO2, resulting in the red-shifts of absorption and promotion of electron injection, respectively. Moreover, the dyes with triphenylamine as the donor display better UV performance and lower trend of aggregation than the dyes with phenothiazine as the donor. Finally, a power conversion efficiency of 8% with chenodeoxycholic acid as the co-absorbant for the DSSC based on Type 1 dyes with triphenylamine is achieved. The results reveal that the donors, the position and number of phenyl unit of the dyes significantly influence the photovoltaic performance of their DSSCs.

Zang, Xu-Feng; Huang, Zu-Sheng; Wu, Han-Lun; Iqbal, Zafar; Wang, Lingyun; Meier, Herbert; Cao, Derong

2014-12-01

240

Monolithic dye laser amplifier  

DOEpatents

A fluid dye laser amplifier for amplifying a dye beam by pump beams has a channel structure defining a channel through which a laseable fluid flows and the dye and pump beams pass transversely to one another through a lasing region. The channel structure is formed with two pairs of mutually spaced-apart and mutually confronting glass windows, which are interlocked and make surface-contacts with one another and surround the lasing region. One of the glass window pairs passes the dye beam and the other passes the pump beams therethrough and through the lasing region. Where these glass window pieces make surface-contacts, glue is used to join the pieces together to form a monolithic structure so as to prevent the dye in the fluid passing through the channel from entering the space between the mutually contacting glass window pieces.

Kuklo, T.C.

1993-03-30

241

Monolithic dye laser amplifier  

DOEpatents

A fluid dye laser amplifier for amplifying a dye beam by pump beams has a channel structure defining a channel through which a laseable fluid flows and the dye and pump beams pass transversely to one another through a lasing region. The channel structure is formed with two pairs of mutually spaced-apart and mutually confronting glass windows, which are interlocked and make surface-contacts with one another and surround the lasing region. One of the glass window pairs passes the dye beam and the other passes the pump beams therethrough and through the lasing region. Where these glass window pieces make surface-contacts, glue is used to join the pieces together to form a monolithic structure so as to prevent the dye in the fluid passing through the channel from entering the space between the mutually contacting glass window pieces.

Kuklo, Thomas C. (Ripon, CA)

1993-01-01

242

TEXTILE DYES AND DYEING EQUIPMENT: CLASSIFICATION, PROPERTIES, AND ENVIRONMENTAL ASPECTS  

EPA Science Inventory

The report gives results of a study of available information on textile dyeing equipment, dyeing procedures, and dye chemistry, to serve as background data for estimating the properties and evaluating the associated risks of new commercial dyestuffs. It reports properties of dyes...

243

Dye system for dye laser applications  

DOEpatents

A dye of the DCM family, [2-methyl-6-[2-(1,2,3,4-tetrahydro-1-methyl-6-quinolinyl)ethenyl]-4H-pyran -4-ylidene]-propanedinitrile, dissolved in 2-phenoxyethanol, is non-mutagenic, stable and efficient, particularly in a pumped continuous wave laser system.

Hammond, Peter R. (Livermore, CA)

1991-01-01

244

Quirks of dye nomenclature. 3. Trypan blue.  

PubMed

Trypan blue is colorant from the 19(th) century that has an association with Africa as a chemotherapeutic agent against protozoan (Trypanosomal) infections, which cause sleeping sickness. The dye still is used for staining biopsies, living cells and organisms, and it also has been used as a colorant for textiles. PMID:24867494

Cooksey, C J

2014-11-01

245

New synthetic routes towards soluble and dissymmetric triphenodioxazine dyes designed for dye-sensitized solar cells.  

PubMed

New ?-conjugated structures are constantly the subject of research in dyes and pigments industry and electronic organic field. In this context, the triphenodioxazine (TPDO) core has often been used as efficient photostable pigments and once integrated in air stable n-type organic field-effect transistor (OFET). However, little attention has been paid to the TPDO core as soluble materials for optoelectronic devices, possibly due to the harsh synthetic conditions and the insolubility of many compounds. To benefit from the photostability of TPDO in dye-sensitized solar cells (DSCs), an original synthetic pathway has been established to provide soluble and dissymmetric molecules applied to a suitable design for the sensitizers of DSC. The study has been pursued by the theoretical modeling of opto-electronic properties, the optical and electronic characterizations of dyes and elaboration of efficient devices. The discovery of new synthetic pathways opens the way to innovative designs of TPDO for materials used in organic electronics. PMID:24677330

Nicolas, Yohann; Allama, Fouzia; Lepeltier, Marc; Massin, Julien; Castet, Frdric; Ducasse, Laurent; Hirsch, Lionel; Boubegtiten, Zahia; Jonusauskas, Gediminas; Olivier, Cline; Toupance, Thierry

2014-03-24

246

Chemical stabilization of laser dyes  

NASA Astrophysics Data System (ADS)

Coumarin laser dyes upon excitation degrade to produce products which absorb at the lasing wavelength. This results in attenuation of dye laser output through interference of stimulated emission. The roles of singlet oxygen and excitation intensity on dye degradation were explored. Singlet oxygen is formed but its reactions with the dye do not appear to be a major cause of dye laser output deterioration. High light intensity results in dye sensitized, solvent oligomerization to yield materials which interfere with dye stimulated emission. 1, 4-Diazabicyclo2,2,2octane (DABCO)inhibits this oligomerization.

Koch, Tad H.

1987-05-01

247

Improvement of sonocatalytic activity of TiO2 by using Yb, N and F-doped Er3+:Y3Al5O12 for degradation of organic dyes.  

PubMed

In this study, several up-conversion luminescence agents (Er(3+):Y3Al5O12, Er(3+):Yb0.2Y2.79Al5O12, Er(3+):Yb0.2Y2.79Al5N0.01O11.99, Er(3+):Yb0.2Y2.79Al5F0.01O11.99 and Er(3+):Yb0.2Y2.79Al5N0.01F0.01O11.98) were synthesized using sol-gel method. And then, the corresponding sonocatalyst (Er(3+):Y3Al5O12/TiO2, Er(3+):Yb0.2Y2.79Al5O12/TiO2, Er(3+):Yb0.2Y2.79Al5N0.01O11.99/TiO2, Er(3+):Yb0.2Y2.79Al5F0.01O11.99/TiO2 and Er(3+):Yb0.2Y2.79Al5N0.01F0.01O11.98/TiO2 coated composites) were prepared by sol-gel coating process. The synthesized up-conversion luminescence agents and their coated composites were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). And that, the sonocatalytic activities were detected through the degradation of Azo Fuchsine (AF) dye in aqueous solution by UV-vis spectroscopy. Some key influences such as heat-treated temperature and heat-treated time on the sonocatalytic activity of Er(3+):YbaY2.99-aNxFyAl5O12-x-y/TiO2 coated composite, as well as ultrasonic irradiation time and initial dye concentration on the sonocatalytic degradation were studied. The results showed that the doping of Yb, N and F into Er(3+):Y3Al5O12/TiO2 significantly enhanced the sonocatalytic activity of Er(3+):Y3Al5O12/TiO2 coated composite in the degradation of organic dyes. Particularly, Er(3+):Yb0.2Y2.79Al5N0.01F0.01O11.98/TiO2 coated composites with 3:7 M ratio heat-treated at 550 C for 60 min showed the highest sonocatalytic activity. At last, the experiments also indicated that the Er(3+):Yb0.2Y2.79Al5N0.01F0.01O11.98/TiO2 coated composites has a good sonocatalytic activity to degrade other organic dyes under ultrasonic irradiation. PMID:23735891

Wang, Jian; Zhou, Songying; Wang, Jun; Li, Shuguang; Gao, Jingqun; Wang, Baoxin; Fan, Ping

2014-01-01

248

Nanowire dye-sensitized solar cells  

Microsoft Academic Search

Excitonic solar cells-including organic, hybrid organic-inorganic and dye-sensitized cells (DSCs)-are promising devices for inexpensive, large-scale solar energy conversion. The DSC is currently the most efficient and stable excitonic photocell. Central to this device is a thick nanoparticle film that provides a large surface area for the adsorption of light-harvesting molecules. However, nanoparticle DSCs rely on trap-limited diffusion for electron transport,

Matt Law; Lori E. Greene; Justin C. Johnson; Richard Saykally; Peidong Yang

2005-01-01

249

DFT study of the effect of different metals on structures and electronic spectra of some organic-metal compounds as sensitizing dyes  

NASA Astrophysics Data System (ADS)

Ruthenium polypyridined-derivative complexes are used in dye-sensitized solar cell [DSSC] as a light to current conversion sensitizer. In order to lower the cost of the DSSC the normal transition metals were used to replace the noble metal ruthenium, and some compounds [ML2L'] (M = Pt, Fe, Ni, Zn; L = isonicotinic acid, L' = maleonitriledithiolate, I = PtL2L', II = FeL2L', III = NiL2L', IV = ZnL2L') were selected as the replacement. The geometries, electronic structures and optical absorption spectra of these compounds have been studied by using density functional theory (DFT) calculation at the B3LYP/LANL2DZ, B3P86/LANL2DZ, B3LYP/GEN level of theory. All the geometric parameters are close to the experimental values. The HOMOs are mainly on the maleonitriledithiolate groups mixed with fewer characters of the metal atom, the LUMOs are mainly on the two pyridine ligands. This means that the electron transition is attributed to the LLCT. The maximum absorptions of complexes are found to be at 351 nm, 806 nm for compound I, and 542 nm for compound II. The maximum absorptions of complexes are found to be at 884 nm for compound III, and 560 nm for compound IV. This means that those compounds may be as a suitable sensitizer for solar energy conversion applications.

Tang, Guodong; Li, Rongqing; Kou, Shanshan; Tang, Tingling; Zhang, Yu; Wang, Yiwei

2014-02-01

250

Identification Of Natural Dyes On Archaeological Textile Objects Using Laser Induced Fluorescent Technique  

SciTech Connect

This study aims to evaluate the use of Laser Fluorescent as a non-destructive technique for identification of natural dyes on archaeological textile objects. In this study wool textile samples were dyed with 10 natural dyes such as cochineal, cutch, henna, indigo, Lac, madder, safflower, saffron, sumac and turmeric. These dyes common present on archaeological textile objects to be used as standard dyed textile samples. These selected natural dyes will be used as known references that can be used a guide to identify unknown archaeological dyes. The dyed textile samples were investigated with laser radiation in different wavelengths to detect the best wavelengths for identification each dye. This study confirms that Laser Florescent is very useful and a rapid technique can be used as a non-destructive technique for identification of natural dyes on archaeological textile objects. The results obtained with this study can be a guide for all conservators in identification of natural organic dyes on archaeological textile objects.

Abdel-Kareem, O. [Conservation Department, Faculty of Archaeology, Cairo University (Egypt); Eltokhy, A.; Harith, M. A. [National Institute of Laser Enhanced Science, Cairo University (Egypt)

2011-09-22

251

Identification Of Natural Dyes On Archaeological Textile Objects Using Laser Induced Fluorescent Technique  

NASA Astrophysics Data System (ADS)

This study aims to evaluate the use of Laser Fluorescent as a non-destructive technique for identification of natural dyes on archaeological textile objects. In this study wool textile samples were dyed with 10 natural dyes such as cochineal, cutch, henna, indigo, Lac, madder, safflower, saffron, sumac and turmeric. These dyes common present on archaeological textile objects to be used as standard dyed textile samples. These selected natural dyes will be used as known references that can be used a guide to identify unknown archaeological dyes. The dyed textile samples were investigated with laser radiation in different wavelengths to detect the best wavelengths for identification each dye. This study confirms that Laser Florescent is very useful and a rapid technique can be used as a non-destructive technique for identification of natural dyes on archaeological textile objects. The results obtained with this study can be a guide for all conservators in identification of natural organic dyes on archaeological textile objects.

Abdel-Kareem, O.; Eltokhy, A.; Harith, M. A.

2011-09-01

252

Dye Application, Manufacture of Dye Intermediates and Dyes  

NASA Astrophysics Data System (ADS)

It is difficult if not impossible to determine when mankind first systematically applied color to a textile substrate. The first colored fabrics were probably nonwoven felts painted in imitation of animal skins. The first dyeings were probably actually little more than stains from the juice of berries. Ancient Greek writers described painted fabrics worn by the tribes of Asia Minor. But just where did the ancient craft have its origins? Was there one original birthplace or were there a number of simultaneous beginnings around the world?

Freeman, H. S.; Mock, G. N.

253

Phenoxazine dyes for dye-sensitized solar cells: relationship between molecular structure and electron lifetime.  

PubMed

A series of metal-free organic dyes with a core phenoxazine chromophore have been synthesized and tested as sensitizers in dye-sensitized solar cells. Overall conversion efficiencies of 6.03-7.40% were reached under standard AM 1.5G illumination at a light intensity of 100 mW cm(-2) . A clear trend in electron lifetime could be seen; a dye with a furan-conjugated linker showed a shorter lifetime relative to dyes with the acceptor group directly attached to the phenoxazine. The addition of an extra donor unit, which bore insulating alkoxyl chains, in the 7-position of the phenoxazine could increase the lifetime even further and, together with additives in the electrolyte to raise the conduction band, an open circuit voltage of 800 mV could be achieved. From photoelectron spectroscopy and X-ray absorption spectroscopy of the dyes adsorbed on TiO(2) particles, it can be concluded that the excitation is mainly of cyano character (i.e., on average, the dye molecules are standing on, and pointing out, from the surface of TiO(2) particles). PMID:21509836

Karlsson, Karl Martin; Jiang, Xiao; Eriksson, Susanna K; Gabrielsson, Erik; Rensmo, Hkan; Hagfeldt, Anders; Sun, Licheng

2011-05-27

254

Degradation of environment pollutant dyes using phytosynthesized metal nanocatalysts  

NASA Astrophysics Data System (ADS)

We present for the first time biogenic reduction and stabilization of gold and silver ions at room temperature using fruit juice of Punica granatum. The formation, morphology and crystalline structure of the synthesized nanoparticles are determined using UV-Visible, XRD and TEM. An attempt to reveal the partial role of phenolic hydroxyls in the reduction of Au3+ and Ag+ is done through FTIR analysis. The synthesized nanoparticles are used as potential catalysts in the degradation of a cationic phenothiazine dye, an anionic mono azo dye and a cationic fluorescent dye. The calculated values of percentage removal of dyes and the rate constants from pseudo first order kinetic data fit give a comparative study on degradation of organic dyes in presence of prepared gold and silver nanoparticles.

MeenaKumari, M.; Philip, Daizy

2015-01-01

255

Simultaneous determination of dyes in wines by HPLC coupled to quadrupole orbitrap mass spectrometry.  

PubMed

A new method combining the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method with ultra high performance liquid chromatography and ESI quadrupole Orbitrap high-resolution MS was developed for the highly accurate and sensitive screening of 69dyes in wines. Response surface methodology was employed to optimize the QuEChERS sample preparation method for the determination of 69 different analytes in wines for the first time. After optimization, the maximum predicted recovery was 99.48% rate for canacert indigo carmine under the optimized conditions of 10 mL acetonitrile, 1.45 g sodium acetate, 107mg primary secondary amine, and 96 mg C18 . For the matrices studied, the recovery rates of the other 68 compounds ranged from 87.2-107.4%, with coefficient of variation <6.4%. The mass accuracy typically obtained is routinely better than 1.6 ppm and only needed to be calibrated once a week. The LODs for the analytes are in the range 1-1000 ?g/kg. This method has been successfully applied on screening of dyes in commercial wines, and it is very useful for the fast screening of different food additives. PMID:24478185

Jia, Wei; Chu, Xiaogang; Ling, Yun; Huang, Junrong; Lin, Yuanhui; Chang, James

2014-04-01

256

Water soluble laser dyes  

DOEpatents

Novel water soluble dyes of the formula 1 are provided by the formula described in the paper wherein R{sup 1} and R{sup 4} are alkyl of 1 to 4 carbon atoms or hydrogen; or R{sup 1}--R{sup 2} or R{sup 2}--R{sup 4} form part of aliphatic heterocyclic rings; R{sup 2} is hydrogen or joined with R{sup 1} or R{sup 4} as described above; R{sup 3} is --(CH{sub 2}){sub m}--SO{sub 3}{sup {minus}}, where m is 1 to 6; X is N, CH or formula 2 given in paper where Y is 2 --SO{sub 3}{sup {minus}} ; Z is 3, 4, 5 or 6 --SO{sub 3}{sup {minus}}. The novel dyes are particularly useful as the active media in water solution dye lasers.

Hammond, P.R.; Feeman, J.F.; Field, G.F.

1998-08-11

257

Hair Dyes and Cancer Risk  

MedlinePLUS

... hair dye ingredients is available from the National Toxicology Program (NTP), an interagency program of the U.S. ... permanent hair dyes: new insights. Critical Reviews in Toxicology 2007; 37(6):521536. [PubMed Abstract] de ...

258

The Comparative Nucleophilicity of Naphthoxide Derivatives in Reactions with a Fast-Red TR Dye: A Discovery-Oriented Capstone Project for the Second-Year Organic Laboratory  

ERIC Educational Resources Information Center

In this experiment, organic chemistry students perform reactions between three naphthyl acetate derivatives and the diazonium salt Fast-Red TR, under basic conditions. The three naphthyl acetate derivatives used in this study are 2-naphthyl acetate (1a), 6-bromo-2-naphthyl acetate (1b) and 1,6-dibromo-2-naphthyl acetate (1c). The two-step, one-pot

Mascarenhas, Cheryl M.

2008-01-01

259

Dye filled security seal  

DOEpatents

A security seal for providing an indication of unauthorized access to a sealed object includes an elongate member to be entwined in the object such that access is denied unless the member is removed. The elongate member has a hollow, pressurizable chamber extending throughout its length that is filled with a permanent dye under greater than atmospheric pressure. Attempts to cut the member and weld it together are revealed when dye flows through a rupture in the chamber wall and stains the outside surface of the member.

Wilson, Dennis C. W. (Tijeras, NM)

1982-04-27

260

Efficiency and photostability of dye-doped solid-state lasers in different hosts  

Microsoft Academic Search

We survey the preparation procedures of pyrromethene (PM) and rhodamine dyes in silica, silicazirconia, organically modified silicate (ormosil) and organic polymer matrices. Absorption and luminescence spectra, as well as decay time fluorescence of pyrromethene dyes are given. The solid-state laser samples were tested and their efficiencies and photostabilities at transversal pumping configuration, are given. Pyrromethene 597 had the best laser

Eli Yariv; Silke Schultheiss; Tsiala Saraidarov; Renata Reisfeld

2001-01-01

261

Planar amine-based dye features the rigidified O-bridged dithiophene ?-spacer: A potential high-efficiency sensitizer for dye-sensitized solar cells application  

NASA Astrophysics Data System (ADS)

This work reports a systematically theoretical study concerning the design of D-?-A organic dyes for DSSC. Two elaborate strategies, namely the rigidity of dithiophene and introduction of strong electron rich/deficient moieties, are proposed. By using the state-of-the-art theoretical calculations, the general influences of fastening atoms (C, N, and O) for ?-spacer rigidification in planar amine-based organic dyes are firstly investigated and elucidated. The properties of isolated dye, dye/(TiO2)38, and dye-I2 interaction are discussed in detail. The results show that, compared with the P2T dye containing dithiophene ?-spacer, its three counterparts with rigidified dithiophene ?-spacers would present the improved absorption properties. We further demonstrate that incorporation of O-bridged dithiophene moiety into the ?-spacer was promising to challenge the photoelectric conversion efficiency 8.29% of P2T. Furthermore, benzothiadiazole (BTD) and 3,4-ethylenedioxythiophene (EDOT) moieties are the well-known ?-skeletons that can effectively tune the electronic structure properties and the light-harvesting ability. Subsequently, a series of dyes are designed through introducing the BTD and EDOT groups into ?-spacer. The calculated results reveal that the dye with the incorporation of EDOT moiety would be more beneficial for photocurrent and photovoltage performance. The current theoretical studies are expected to be very relevant for the molecular design of D-?-A organic dyes in DSSC.

Li, Wei; Bai, Fu-Quan; Chen, Jie; Wang, Jian; Zhang, Hong-Xing

2015-02-01

262

Alzheimer's Dye Test?  

ERIC Educational Resources Information Center

Massachusetts Institute of Technology (MIT) scientists have developed a new dye that could offer noninvasive early diagnosis of Alzheimer's disease, a discovery that could aid in monitoring the progression of the disease and in studying the efficacy of new treatments to stop it. The work is published in Angewandte Chemie. Today, doctors can only

Science Teacher, 2005

2005-01-01

263

[Vital dyes in chromovitrectomy].  

PubMed

The aim of this article is to present the current data with regard to the application of vital dyes during vitreoretinal surgery, 'chromovitrectomy', as well as to overview the current literature regarding the properties of dyes, techniques of application, indications and complications in chromovitrectomy. A large body of published research has recently addressed the toxicity profile of indocyanine green for chromovitrectomy. Experimental data demonstrate dose-dependent toxicity of indocyanine green to various retinal cells. Newer generation vital dyes for chromovitrectomy include trypan blue, patent blue, triamcinolone acetonide, infracyanine green, sodium fluorescein, bromophenol blue, fluorometholone acetate and brilliant blue. Novel instruments may enable a selective painting of preretinal tissues during chromovitrectomy. This review suggests that the field of chromovitrectomy represents an expanding area of research. The first line agents for internal limiting membrane staining in chromovitrectomy are indocyanine green, infracyanine green, and brilliant blue. Patent blue, bromophenol blue and trypan blue arose as outstanding biostains for visualization of epiretinal membranes. Novel dyes available for chromovitrectomy deserve further investigation. PMID:20098913

Dib, Eduardo; Rodrigues, Eduardo Bchelle; Maia, Maurcio; Meyer, Carsten H; Penha, Fernando Marcondes; Furlani, Bruno de Albuquerque; Costa, Elaine de Paula Fiod; Farah, Michel Eid

2009-01-01

264

Enhancement of the photoproperties of solid-state TiO2|dye|CuI cells by coupling of two dyes  

NASA Astrophysics Data System (ADS)

The electronic coupling of a natural pigment extracted from pomegranate fruits (rich with cyanin and exist as flavylium at natural PH) with an organic dye mercurochrome enhanced the performance of solid-state TiO2|dye|CuI-type photovoltaic cells sensitized from pomegranate pigments or mercurochrome individually.

Sirimanne, P. M.; Senevirathna, M. K. I.; Premalal, E. V. A.; Pitigala, P. K. D. D. P.

2006-06-01

265

A density functional theory and time-dependent density functional theory investigation on the anchor comparison of triarylamine-based dyes  

Microsoft Academic Search

To understand the effects of the anchor part in organic dyes on the energy conversion efficiency of dye-sensitized solar cells (DSCs), two different anchor groups used in metal-free triphenylamine (TPA)-based organic dyes for DSCs have been theoretically compared. Density functional theory (DFT) and time-dependent DFT (TDDFT) study of geometry properties, excitations, and electronic structures of triarylamine-based dyes (TC1 and TPAR1)

Bo Peng; Siqi Yang; Lanlan Li; Fangyi Cheng; Jun Chen

2010-01-01

266

Fiberized fluorescent dye microtubes  

NASA Astrophysics Data System (ADS)

In the present work we study the effect of the length of fluorescent dye-filled micro-capillaries on the fluorescence spectra. Two types of micro-capillaries have been studied: a 100 ?m inner diameter fused silica capillary with a transparent coating and one of the holes of a fiber optic glass ferrule with 125 ?m inner diameter. The tubes were filled with solutions of Rhodamine 6G dissolved in ethanol and then in glycerin. Experimental data show that the maximum fluorescence and the largest spectral widths are observed for a sample length of about 0.25 mm for the used concentration. This results show that miniature tunable fiberized dye lasers can be developed using available standard micro-and fibre-optic components.

Vladev, Veselin; Eftimov, Tinko

2013-03-01

267

Painting With Natural Dyes  

NSDL National Science Digital Library

This activity is part of an integrated elementary unit called "Painted Tipis." The unit is best taught in the fall in conjunction with the September celebration "American Indian Heritage Week." It integrates lessons on literature through legends and myths, language (Blackfeet), and mathematics through structural components of the tipi. The activity introduces the students to the art of dyeing as used in ancestral tipi paintings. Historical cultural ties are an integral part of the Native American students learning and this unit provides those connections. The purpose of this lesson is to provide elementary students with the opportunity to explore, identify and locate area plants. The inquiry cooperative learning component of this lesson will be to determine the color (dye) producing possibilities of the plant. Students will also plan and carry out an experiment to produce the dyestuff of the plant as well as create possible mordants, which is a chemical or metallic compound that will "fasten" the color to the fabric.

Barbara Arrowtop (Heart Butte School)

1999-07-01

268

High performance electrocatalyst consisting of CoS nanoparticles on an organized mesoporous SnO2 film: its use as a counter electrode for Pt-free, dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

High energy conversion efficiencies of 6.6% and 7.5% are demonstrated in solid and liquid states, Pt-free, dye-sensitized solar cells (DSSCs), respectively, based on CoS nanoparticles on an organized mesoporous SnO2 (om-SnO2) counter electrode. These results correspond to improvements of 14% and 9%, respectively, compared to a conventional Pt counter electrode and are among the highest values reported for Pt-free DSSCs. The om-SnO2 layer plays a pivotal role as a platform to deposit a large amount of highly electrocatalytically active CoS nanoparticles via a facile solvothermal reaction. The om-SnO2 platform with a high porosity, larger pores, and good interconnectivity is derived from a poly(vinyl chloride)-g-poly(oxyethylene methacrylate) (PVC-g-POEM) graft copolymer template, which provides not only improved interaction sites for the formation of CoS nanoparticles but also enhanced electron transport. The structural, morphological, chemical, and electrochemical properties of CoS on the om-SnO2 platform are investigated using field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) measurements. The performance enhancement results from the excellent electron transport at the fluorine-doped tin oxide (FTO)/counter electrode/electrolyte interface, reduced resistance at the FTO/CoS interface, and better catalytic reduction at the counter electrode/electrolyte interface.High energy conversion efficiencies of 6.6% and 7.5% are demonstrated in solid and liquid states, Pt-free, dye-sensitized solar cells (DSSCs), respectively, based on CoS nanoparticles on an organized mesoporous SnO2 (om-SnO2) counter electrode. These results correspond to improvements of 14% and 9%, respectively, compared to a conventional Pt counter electrode and are among the highest values reported for Pt-free DSSCs. The om-SnO2 layer plays a pivotal role as a platform to deposit a large amount of highly electrocatalytically active CoS nanoparticles via a facile solvothermal reaction. The om-SnO2 platform with a high porosity, larger pores, and good interconnectivity is derived from a poly(vinyl chloride)-g-poly(oxyethylene methacrylate) (PVC-g-POEM) graft copolymer template, which provides not only improved interaction sites for the formation of CoS nanoparticles but also enhanced electron transport. The structural, morphological, chemical, and electrochemical properties of CoS on the om-SnO2 platform are investigated using field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) measurements. The performance enhancement results from the excellent electron transport at the fluorine-doped tin oxide (FTO)/counter electrode/electrolyte interface, reduced resistance at the FTO/CoS interface, and better catalytic reduction at the counter electrode/electrolyte interface. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr05779a

Park, Jung Tae; Lee, Chang Soo; Kim, Jong Hak

2014-12-01

269

High performance electrocatalyst consisting of CoS nanoparticles on an organized mesoporous SnO2 film: its use as a counter electrode for Pt-free, dye-sensitized solar cells.  

PubMed

High energy conversion efficiencies of 6.6% and 7.5% are demonstrated in solid and liquid states, Pt-free, dye-sensitized solar cells (DSSCs), respectively, based on CoS nanoparticles on an organized mesoporous SnO2 (om-SnO2) counter electrode. These results correspond to improvements of 14% and 9%, respectively, compared to a conventional Pt counter electrode and are among the highest values reported for Pt-free DSSCs. The om-SnO2 layer plays a pivotal role as a platform to deposit a large amount of highly electrocatalytically active CoS nanoparticles via a facile solvothermal reaction. The om-SnO2 platform with a high porosity, larger pores, and good interconnectivity is derived from a poly(vinyl chloride)-g-poly(oxyethylene methacrylate) (PVC-g-POEM) graft copolymer template, which provides not only improved interaction sites for the formation of CoS nanoparticles but also enhanced electron transport. The structural, morphological, chemical, and electrochemical properties of CoS on the om-SnO2 platform are investigated using field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) measurements. The performance enhancement results from the excellent electron transport at the fluorine-doped tin oxide (FTO)/counter electrode/electrolyte interface, reduced resistance at the FTO/CoS interface, and better catalytic reduction at the counter electrode/electrolyte interface. PMID:25429695

Park, Jung Tae; Lee, Chang Soo; Kim, Jong Hak

2014-12-11

270

Dye-coated europium monosulfide  

SciTech Connect

Nanoparticles of EuS were synthesized using europium dithiocarbamate complexes. The resulting nanoparticles were coated with the dye, 1-pyrene carboxylic acid and the resulting material was characterized using X-ray powder diffraction, TEM, and UV-visible spectroscopy. Fluorescence spectroscopy was used to determine the relative energy of the conduction band edge to the excited state energy of the dye. -- Graphical abstract: Dye sensitized magnetic semiconductor materials were prepared by synthesizing EuS nanoparticles using single source precursors and coating with the dye, 1-pyrene carboxylic acid. Display Omitted highlights: > Synthesized EuS nanoparticles, 11{+-}2.4 nm characterized using XRD, TEM, and UV-vis. spect. > Grafted a dye to the surface and characterized the product using XRD, FTIR, UV-vis., and TEM. > Studied the photophysical properties using fluorescence spectroscopy. > Determined the relative dye excited state to the conduction band of the semiconductor.

Kar, Srotoswini [Department of Chemistry, Georgetown University, Washington D.C. 20057 (United States); Dollahon, Norman R. [Department of Biology, Villanova University, Villanova, PA 19085 (United States); Stoll, Sarah L., E-mail: sls55@georgetown.ed [Department of Chemistry, Georgetown University, Washington D.C. 20057 (United States)

2011-05-15

271

The Chemistry of Plant and Animal Dyes.  

ERIC Educational Resources Information Center

Provides a brief history of natural dyes. Chemical formulas are provided for flavonoids, luteolin, genistein, brazilin, tannins, terpenes, naphthoquinone, anthraquinone, and dyes with an alkaloid structure. Also discusses chemical background of different dye processes. (CS)

Sequin-Frey, Margareta

1981-01-01

272

Electrochemical oxidation of a textile dye wastewater using a Pt\\/Ti electrode  

Microsoft Academic Search

Textile dye wastewater (TDW) from a reactive azo dyeing process was treated by an electrochemical oxidation method using Ti\\/Pt as anode and stainless steel 304 as cathode. Due to the strong oxidizing potential of the chemicals produced (chlorine, oxygen, hydroxyl radicals and other oxidants) when the wastewater was passed through the electrolytic cell the organic pollutants were oxidized to carbon

A. G Vlyssides; M Loizidou; P. K Karlis; A. A Zorpas; D Papaioannou

1999-01-01

273

Gel Electrophoresis of Dyes  

NSDL National Science Digital Library

In this experiment related to plant biotechnology, learners discover how to prepare and load an electrophoresis gel. They will then run the gels in an electrophoresis system to separate several dyes that are of different molecular sizes and carry different charges. This technique is fundamental to many of the procedures used in biotechnology. This lesson guide includes background information for the educator, safety precautions, and questions with answers for learners. For safety reasons, adult supervision is recommended. Modifications for use with younger learners are described in a related PDF (see related resource).

Stephens, Janice; Leach, Jan

2011-01-01

274

Sampling and identification of natural dyes in historical maps and drawings by liquid chromatography with diode-array detection.  

PubMed

A simple and rapid liquid chromatographic with diode-array UV-vis spectrophotometric detection (HPLC-DAD) method for identification of natural dyes has been developed. Chromatographic retention of carminic acid, indigotin, crocetin, gambogic acid, alizarin and purpurin has been studied. The mobile phase consisted of 40 mM SDS-10 mM phosphate buffer solution (pH 2.3)-0.1% TFA (eluent A) and acetonitrile (eluent B) using a programmed gradient (5% B to 95% B). Analyses were carried out on a Phenomenex, Luna 5u NH2 100(a) column (250 mm x 4.60 mm i.d., 5 microm particle) and the operating conditions were: 0.6 ml min(-1) flow rate, 20 microl volume injection and 35 degrees C column temperature. Extracts of samples of natural dyes taken from historical maps belonging to The Royal Chancellery Archives in Granada were successfully analyzed using the proposed method including a new technique for sampling. PMID:16759664

Blanc, Rosario; Espejo, Teresa; Lpez-Montes, Ana; Torres, David; Crovetto, Guillermo; Navaln, Alberto; Vlchez, Jos Luis

2006-07-28

275

FM-dyes as experimental probes for dissecting vesicle trafficking in living plant cells.  

PubMed

FM-dyes are widely used to study endocytosis, vesicle trafficking and organelle organization in living eukaryotic cells. The increasing use of FM-dyes in plant cells has provoked much debate with regard to their suitability as endocytosis markers, which organelles they stain and the precise pathways they follow through the vesicle trafficking network. A primary aim of this article is to assess critically the current status of this debate in plant cells. For this purpose, background information on the important characteristics of the FM-dyes, and of optimal dye concentrations, conditions of dye storage, and staining and imaging protocols, are provided. Particular emphasis is placed on using the FM-dyes in double labelling experiments to identity specific organelles. In this way, staining of the Golgi with FM4-64 has been demonstrated for the first time. PMID:15102063

Bolte, S; Talbot, C; Boutte, Y; Catrice, O; Read, N D; Satiat-Jeunemaitre, B

2004-05-01

276

Fluorometric procedures for dye tracing  

USGS Publications Warehouse

This manual describes the current fluorometric procedures used by the U.S. Geological Survey in dye tracer studies such as time of travel, dispersion, reaeration, and dilution-type discharge measurements. The advantages of dye tracing are (1) low detection and measurement limits and (2) simplicity and accuracy in measuring dye tracer concentrations using fluorometric techniques. The manual contains necessary background information about fluorescence, dyes, and fluorometers and a description of fluorometric operation and calibration procedures as a guide for laboratory and field use. The background information should be useful to anyone wishing to experiment with dyes, fluorometer components, or procedures different from those described. In addition, a brief section on aerial photography is included because of its possible use to supplement ground-level fluorometry.

Wilson, James F.

1968-01-01

277

Fluorometric procedures for dye tracing  

USGS Publications Warehouse

This manual describes the current fluorometric procedures used by the U.S. Geological Survey in dye tracer studies such as time of travel, dispersion, reaeration, and dilution-type discharge measurements. The outstanding characteristics of dye tracing are: (1) the low detection and measurement limits, and (2) the simplicity and accuracy of measuring dye tracer concentrations using fluorometric techniques. The manual contains necessary background information about fluorescence, dyes, and fluorometers and a description of fluorometric operation and calibration procedures as a general guide for laboratory and field use. The background information should be useful to anyone wishing to experiment with dyes, fluorometer components, or procedures different from those described. In addition, a brief section is included on aerial photography because of its possible use to supplement ground-level fluorometry. (USGS)

Wilson, James E., Jr.; Cobb, E.D.; Kilpatrick, F.A.

1984-01-01

278

Fluorometric procedures for dye tracing  

USGS Publications Warehouse

This manual describes the current fluorometric procedures used by the U.S. Geological Survey in dye tracer studies such as time of travel, dispersion, reaeration, and dilution-type discharge measurements. The advantages of dye tracing are (1) low detection and measurement limits and (2) simplicity and accuracy in measuring dye tracer concentrations using fluorometric techniques. The manual contains necessary background information about fluorescence, dyes, and fluorometers and a description of fluorometric operation and calibration procedures as a guide for laboratory and field use. The background information should be useful to anyone wishing to experiment with dyes, fluorometer components, or procedures different from those described. In addition, a brief section on aerial photography is included because of its possible use to supplement ground-level fluorometry.

Wilson, James F.; Cobb, Ernest D.; Kilpatrick, F.A.

1986-01-01

279

Contact urticaria to cosmetic and industrial dyes.  

PubMed

Contact urticaria (CU) defines the weal-and-flare reaction that occurs after external cutaneous contact with a causative agent. These reactions often cause discomfort for patients, affect their quality of life, and in severe cases may be life-threatening. Some dyes are known to be urticariogens. Many people have daily exposure to these urticariogens, because of the widespread use of dyes, for example in textiles, cosmetics and foods. We reviewed industrial and cosmetic dyes such as hair dyes, basic blue 99 dye, patent blue dyes, henna, red dyes, curcumin and reactive dyes, which can potentially cause CU. Overall, the reported cases of CU lacked appropriate controls. Hair-dye constituents such as preservatives and intensifiers may play an important role as causative agents of CU. We recommend appropriate protection guidelines to reduce the incidence of CU in high-risk groups such as hairdressers, dye-factory workers or workers in dye-related industries. PMID:20456377

Davari, P; Maibach, H I

2011-01-01

280

Classification and naming of dyes, stains and fluorochromes.  

PubMed

A classification of dyes and other colorants is proposed, based on the chemical features responsible for their visibility and generally consonant with the writings of modern color chemists. The scheme differs in several respects from that of the Colour Index (CI), but it retains some traditional small groups of dyes that include biological stains. Natural dyes, recognized as a group in the CI, are placed with or near synthetic dyes with identical or similar chromophores. The new scheme also provides categories for dyes and fluorochromes that do not have places in the CI classification. Some CI categories, including lactones, aminoketones and hydroxyketones, are not recognized in this new scheme, which is adopted in the forthcoming 10th edition of Conn's Biological Stains: a Handbook of Dyes and Fluorochromes for Use in Biology and Medicine. Some rules are also set out for the spelling of trivial names, which has long been inconsistent in scientific literature. The ending '-ine' is used for compounds derived from organic bases (e.g., fuchsine and thionine, not fuchsin or thionin), and names ending in '-in' are for compounds that are not bases or their derivatives (e.g., eosin and phloxin, not eosine or phloxine). Initial capital letters are used only for words that are names of people or places (e.g., Nile blue or Congo red) and for the 'generic' components of CI application names (as in Acid yellow 36). Other words, including trade names that have fallen into common usage are not capitalized (e.g., alcian blue, biebrich scarlet, coomassie blue). The recommended spellings of some dyes differ from those commonly seen in vendors' catalogs and in biological publications, but they are generally consistent with English and American dictionaries, with recent writings in English by color chemists, and with the trivial names of other organic compounds. PMID:11871748

Kiernan, J A

2001-01-01

281

Suitable Reference Gene Selection for Different Strains and Developmental Stages of the Carmine Spider Mite, Tetranychus cinnabarinus, using Quantitative Real-Time PCR  

PubMed Central

Reference genes are used as internal controls in gene expression studies, but their expression levels vary according to tissue types and experimental treatments. Quantitative real-time PCR (qPCR) is the most sensitive technique for transcript quantification provided that gene transcription patterns are normalized to an evaluated reference gene. In this study, the suitability of eight commonly used genes (??-actin, 5.8SrRNA, ??-TUB, GAPDH, RPL13a, RPS18, TBP, SDHA) were cloned and investigated to find the most stable candidates for normalizing real-time PCR data generated from the four different strains (abamectin-resistant, fenpropathrin-resistant, omethoate-resistant, and susceptible strains) and different developmental stages (eggs, protonymphs, nymphs, and adults) of carmine spider mite, Tetranychus cinnabarinus (Boisduval) (Acarina: Tetranychidae). The stability of gene expression was assessed using two different analysis programs, geNorm and NormFinder. Using these analyses, RPS18 and 5.8SrRNA had the most stable expression regardless of the four different strains, whereas RPS18 and ??-TUB were expressed most stably in different developmental stages. PMID:21265619

Sun, W.; Jin, Y.; He, L; Lu, W-C.; Li, M.

2010-01-01

282

Dye-sensitized solar cells  

DOEpatents

A low-cost dye-sensitized Schottky barrier solar cell is comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent. 3 figs.

Skotheim, T.A.

1980-03-04

283

Dye-sensitized solar cells  

DOEpatents

A low-cost dye-sensitized Schottky barrier solar cell comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent.

Skotheim, Terje A. [Berkeley, CA

1980-03-04

284

Never say dye  

PubMed Central

Recent years have seen a remarkable increase in the number of publications dealing with the application of epifluorescence microscopy in cell biology. This can be widely attributed to the development of state-of-the-art image processing programs, as well as the development of new reagents/probes, which allow the labeling of most cell structures, organelles and metabolites with high specificity. However, the use of a specific fluorescent dye, 3,3?-dihexyloxacarbocyanine iodide (DiOC6), has been recently revisited and several new application potentials have emerged. The goal of this mini-review is to provide an up-to-date overview of the multiple roles of this multifaceted probe. PMID:22476459

2012-01-01

285

Reagent ultrafiltration purification of water contaminated with reactive dyes  

Microsoft Academic Search

Wastewater from the textile industry is characterized by a varying and often unidentified composition. The basic contaminants normally present include surfactants, organic and mineral acids, bleachers and dyes. These substances deteriorate the quality of the water downstream via direct contamination and through the occurrence of secondary processes. The use of reagent treatment methods does not always lead to sufficient purification.

S Petrov; PA Stoichev

2002-01-01

286

Convenient Microscale Synthesis of a Coumarin Laser Dye Analog  

ERIC Educational Resources Information Center

Coumarin (2H-1-benzopyran-2-one) and its derivatives constitute a fascinating class of organic substances that are utilized industrially in areas such as cosmetics, food preservatives, insecticides and fluorescent laser dyes. The product can be synthesized, purified, and characterized within two hours with benefits of microscale reactivity being

Aktoudianakis, Evangelos; Dicks, Andrew P.

2006-01-01

287

Decolorization and Detoxification of Textile Dyes with a Laccase from Trametes hirsuta  

PubMed Central

Trametes hirsuta and a purified laccase from this organism were able to degrade triarylmethane, indigoid, azo, and anthraquinonic dyes. Initial decolorization velocities depended on the substituents on the phenolic rings of the dyes. Immobilization of the T. hirsuta laccase on alumina enhanced the thermal stabilities of the enzyme and its tolerance against some enzyme inhibitors, such as halides, copper chelators, and dyeing additives. The laccase lost 50% of its activity at 50 mM NaCl while the 50% inhibitory concentration (IC50) of the immobilized enzyme was 85 mM. Treatment of dyes with the immobilized laccase reduced their toxicities (based on the oxygen consumption rate of Pseudomonas putida) by up to 80% (anthraquinonic dyes). Textile effluents decolorized with T. hirsuta or the laccase were used for dyeing. Metabolites and/or enzyme protein strongly interacted with the dyeing process indicated by lower staining levels (K/S) values than obtained with a blank using water. However, when the effluents were decolorized with immobilized laccase, they could be used for dyeing and acceptable color differences (?E*) below 1.1 were measured for most dyes. PMID:10919791

Abadulla, Elias; Tzanov, Tzanko; Costa, Silgia; Robra, Karl-Heinz; Cavaco-Paulo, Artur; Gbitz, Georg M.

2000-01-01

288

Dye molecules in electrolytes: new approach for suppression of dye-desorption in dye-sensitized solar cells  

PubMed Central

The widespread commercialization of dye-sensitized solar cells remains limited because of the poor long-term stability. We report on the influence of dye-molecules added in liquid electrolyte on long-term stability of dye-sensitized solar cells. Dye-desorption from the TiO2 surface during long-term cycling is one of the decisive factors that degrade photocurrent densities of devices which in turn determine the efficiencies of the devices. For the first time, desorption of dye from the TiO2 surface could be suppressed by controlling thermodynamic equilibrium; by addition of dye molecules in the electrolyte. The dye molecules in the electrolyte can suppress the driving forces for the adsorbed dye molecules to be desorbed from TiO2 nanoparticles. As a result, highly enhanced device stabilities were achieved due to the reduction of dye-desorption although there was a little decrease in the initial efficiencies.

Heo, Nansra; Jun, Yongseok; Park, Jong Hyeok

2013-01-01

289

Laser properties and photostabilities of laser dyes doped in ORMOSILs  

NASA Astrophysics Data System (ADS)

Laser dyes such as rhodamine B, rhodamine 6G, pyrromethene 567, perylene orange and perylene red were doped into GPTMS-, MTES- and VTES-derived organically modified silicates (ORMOSILs) by sol-gel process. A longitudinal pumped solid-state dye laser was established with a Q-switched Nd:YAG laser source. The lifetimes of these dyes in various ORMOSILs were investigated by using such an experimental setup at a pump repetition rate of 2 Hz and pump intensity of 0.1 or 1.4 J/cm 2. The lifetime of 60 000 pulses, 50 GJ/mol in normalized photostability, was obtained for the pyrromethene 567 doped in MTES-derived ORMOSIL with the net sample thickness of 4 mm when its output energy declined to 50% of its initial value. The slope efficiencies of pyrromethene 567 and perylene orange in various host media were also measured.

Yang, Yu; Wang, Minquan; Qian, Guodong; Wang, Zhiyu; Fan, Xianping

2004-01-01

290

Dye laser amplifier including a dye cell contained within a support vessel  

DOEpatents

A large (high flow rate) dye laser amplifier in which a continuous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of greater than 30 gallons/minute at a static pressure greater than 150 pounds/square inch and a specifically designed support vessel for containing the dye cell. 6 figs.

Davin, J.

1992-12-01

291

Analysis of Insecticide Resistance-Related Genes of the Carmine Spider Mite Tetranychus cinnabarinus Based on a De Novo Assembled Transcriptome  

PubMed Central

The carmine spider mite (CSM), Tetranychus cinnabarinus, is an important pest mite in agriculture, because it can develop insecticide resistance easily. To gain valuable gene information and molecular basis for the future insecticide resistance study of CSM, the first transcriptome analysis of CSM was conducted. A total of 45,016 contigs and 25,519 unigenes were generated from the de novo transcriptome assembly, and 15,167 unigenes were annotated via BLAST querying against current databases, including nr, SwissProt, the Clusters of Orthologous Groups (COGs), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO). Aligning the transcript to Tetranychus urticae genome, the 19255 (75.45%) of the transcripts had significant (e-value <10?5) matches to T. urticae DNA genome, 19111 sequences matched to T. urticae proteome with an average protein length coverage of 42.55%. Core Eukaryotic Genes Mapping Approach (CEGMA) analysis identified 435 core eukaryotic genes (CEGs) in the CSM dataset corresponding to 95% coverage. Ten gene categories that relate to insecticide resistance in arthropod were generated from CSM transcriptome, including 53 P450-, 22 GSTs-, 23 CarEs-, 1 AChE-, 7 GluCls-, 9 nAChRs-, 8 GABA receptor-, 1 sodium channel-, 6 ATPase- and 12 Cyt b genes. We developed significant molecular resources for T. cinnabarinus putatively involved in insecticide resistance. The transcriptome assembly analysis will significantly facilitate our study on the mechanism of adapting environmental stress (including insecticide) in CSM at the molecular level, and will be very important for developing new control strategies against this pest mite. PMID:24830288

Liu, Yanchao; Liu, Xing; Chen, Qiushuang; Peng, Miao; Wang, Xiangzun; Shen, Guangmao; He, Lin

2014-01-01

292

A vibrational spectroscopic and principal component analysis of triarylmethane dyes by comparative laboratory and portable instrumentation.  

PubMed

This contribution examines the utility of vibrational spectroscopy by bench and portable Raman/surface enhanced Raman and infrared methods for the investigation of ten early triarlymethane dye powder references and dye solutions applied on paper. The complementary information afforded by the techniques is shown to play a key role in the identification of specific spectral marker ranges to distiguish early synthetic dyes of art-historical interest through the elaboration of an in-house database of modern organic dyes. Chemometric analysis has permitted a separation of data by the discrimination of di-phenyl-naphthalenes and triphenylmethanes (di-amino and tri-amino derivatives). This work serves as a prelude to the validation of a non-invasive working method for in situ characterization of these synthetic dyes through a careful comparison of respective strengths and limitations of each portable technique. PMID:24252295

Doherty, B; Vagnini, M; Dufourmantelle, K; Sgamellotti, A; Brunetti, B; Miliani, C

2014-01-01

293

Cobalt electrolyte/dye interactions in dye-sensitized solar cells: a combined computational and experimental study.  

PubMed

We report a combined experimental and computational investigation to understand the nature of the interactions between cobalt redox mediators and TiO(2) surfaces sensitized by ruthenium and organic dyes, and their impact on the performance of the corresponding dye-sensitized solar cells (DSSCs). We focus on different ruthenium dyes and fully organic dyes, to understand the dramatic loss of efficiency observed for the prototype Ru(II) N719 dye in conjunction with cobalt electrolytes. Both N719- and Z907-based DSSCs showed an increased lifetime in iodine-based electrolyte compared to the cobalt-based redox shuttle, while the organic D21L6 and D25L6 dyes, endowed with long alkoxy chains, show no significant change in the electron lifetime regardless of employed electrolyte and deliver a high photovoltaic efficiency of 6.5% with a cobalt electrolyte. Ab initio molecular dynamics simulations show the formation of a complex between the cobalt electrolyte and the surface-adsorbed ruthenium dye, which brings the [Co(bpy)(3)](3+) species into contact with the TiO(2) surface. This translates into a high probability of intercepting TiO(2)-injected electrons by the oxidized [Co(bpy)(3)](3+) species, lying close to the N719-sensitized TiO(2) surface. Investigation of the dye regeneration mechanism by the cobalt electrolyte in the Marcus theory framework led to substantially different reorganization energies for the high-spin (HS) and low-spin (LS) reaction pathways. Our calculated reorganization energies for the LS pathways are in excellent agreement with recent data for a series of cobalt complexes, lending support to the proposed regeneration pathway. Finally, we systematically investigate a series of Co(II)/Co(III) complexes to gauge the impact of ligand substitution and of metal coordination (tris-bidentate vs bis-tridentate) on the HS/LS energy difference and reorganization energies. Our results allow us to trace structure/property relations required for further development of cobalt electrolytes for DSSCs. PMID:23113640

Mosconi, Edoardo; Yum, Jun-Ho; Kessler, Florian; Gmez Garca, Carlos J; Zuccaccia, Cristiano; Cinti, Antonio; Nazeeruddin, Mohammad K; Grtzel, Michael; De Angelis, Filippo

2012-11-28

294

Degradation of Textile Dyes Ponceau-S and Sudan IV Using RecentlyDeveloped Photocatalyst, Immobilized Resin Dowex11  

Microsoft Academic Search

Problem statement: In present study, we selected a model dyes Ponceau S and Sudan IV, to test a recently developed photo catalyst methylene blue immobilized resin dowex-11. Approach: This is a light-activated process that has been successfull y applied to remove organic and inorganic dyes of textile industries. Results: The reactor, made of glass slides (tubes) coated w ith a

R. C. Meena; Ram Babu Pachwarya; Vijay Kumar Meena; Shakuntla Arya

2009-01-01

295

LASERS: A microporous glass-polymer composite as a new material for solid-state dye lasers: II. Lasing properties  

Microsoft Academic Search

The conversion efficiency and service life of the laser elements based on a polymer-filled microporous glass (PFMPG) composite doped with organic dyes are studied. It is shown that both the conversion efficiency and the service life of the laser elements achieve the values obtained for the same dyes in bulk polymer elements. Good lasing characteristics of the elements studied are

H. R. Aldag; S. M. Dolotov; M. F. Koldunov; Ya V. Kravchenko; Aleksandr A. Manenkov; D. P. Pacheco; E. P. Ponomarenko; A. V. Reznichenko; G. P. Roskova; T. S. Tsekhomskaya

2000-01-01

296

Soybean peroxidase-mediated degradation of an azo dye a detailed mechanistic study  

PubMed Central

Background Peroxidases are emerging as an important class of enzymes that can be used for the efficient degradation of organic pollutants. However, detailed studies identifying the various intermediates produced and the mechanisms involved in the enzyme-mediated pollutant degradation are not widely published. Results In the present study, the enzymatic degradation of an azo dye (Crystal Ponceau 6R, CP6R) was studied using commercially available soybean peroxidase (SBP) enzyme. Several operational parameters affecting the enzymatic degradation of dye were evaluated and optimized, such as initial dye concentration, H2O2 dosage, mediator amount and pH of the solution. Under optimized conditions, 40ppm dye solution could be completely degraded in under one minute by SBP in the presence of H2O2 and a redox mediator. Dye degradation was also confirmed using HPLC and TOC analyses, which showed that most of the dye was being mineralized to CO2 in the process. Conclusions Detailed analysis of metabolites, based on LC/MS results, showed that the enzyme-based degradation of the CP6R dye proceeded in two different reaction pathways- via symmetric azo bond cleavage as well as asymmetric azo bond breakage in the dye molecule. In addition, various critical transformative and oxidative steps such as deamination, desulfonation, keto-oxidation are explained on an electronic level. Furthermore, LC/MS/MS analyses confirmed that the end products in both pathways were small chain aliphatic carboxylic acids. PMID:24308857

2013-01-01

297

Tuning the electrical and optical properties of diketopyrrolopyrrole complexes for panchromatic dye-sensitized solar cells.  

PubMed

A series of metal-free organic dyes that were bridged by a diketopyrrolopyrrole moiety and were composed of indoline and triphenylamine as donor groups and furan and benzene as conjugated spacer groups were designed and synthesized for use in dye-sensitized solar cells (DSCs). The photophysical properties, electrochemical properties, and performance of the DSCs were related to the structure of their corresponding dyes. Their absorption spectra broadened upon the introduction of the indoline and heterocyclic furan moieties through fine-tuning of their molecular configuration. The overall conversion efficiencies of DSCs that were based on these dyes ranged from 5.14-6.53%. Among the four dyes that were tested, indoline-based ID01 and ID02 showed higher efficiencies (6.35% and 6.53%) as a result of their improved light-harvesting efficiency and larger electron driving force. The ID01 dye, which contained an indoline moiety as an electron donor and a furan group as a ?-conjugated linker, showed an excellent monochromatic incident-photon-to-current-conversion efficiency (IPCE) spectrum (350-650?nm) with a maximum value of 78% in the high plateau region and an onset value close to 800?nm. Intensity-modulated photovoltage spectroscopy (IMVS) and impedance spectroscopy (IS) revealed that dyes that contained benzene conjugation spacers suppressed the charge-recombination rate more efficiently than dyes that contained furan spacers, thereby resulting in improved photovoltage. PMID:23015395

Qu, Sanyin; Qin, Chuanjiang; Islam, Ashraful; Hua, Jianli; Chen, Han; Tian, He; Han, Liyuan

2012-12-01

298

Toward ultra-stable fluorescent dyes for single-molecule spectroscopy  

NASA Astrophysics Data System (ADS)

The wide-spread use of fluorescent dyes in molecular diagnostics and fluorescence microscopy together with new developments such as single-molecule fluorescence spectroscopy provide researchers from various disciplines with an ever expanding toolbox. Single-molecule fluorescence spectroscopy relies to a large extent on extraordinary bright and photostable organic fluorescent dyes such as rhodamine- or cyanine- derivatives. While in the last decade singlemolecule equipment and methodology have significantly advanced and in some cases reached theoretical limits (e.g. detectors approaching unity quantum yields), instable emission ("blinking") and photobleaching become more and more the bottleneck of further development and spreading of single-molecule fluorescence studies. In recent years, agents and recipes have been developed to increase the photostability of conventional fluorescent dyes. Here, we investigate some of these strategies at the single-molecule level. In particular, we focus on the dye selection criteria for multi-color applications. We investigate fluorescent dyes from the rhodamine, carborhodamine, cyanine, and oxazine family and show that within one dye class the photophysical properties are very similar but that dyes from different classes show strikingly different properties. These findings facilitate dye selection and provide improved chemical environment for demanding fluorescence microscopic applications.

Kasper, Robert; Heilemann, Mike; Tinnefeld, Philip; Sauer, Markus

2007-07-01

299

Influence of solvent and bridge structure in alkylthio-substituted triphenylamine dyes on the photovoltaic properties of dye-sensitized solar cells.  

PubMed

Three new triphenylamine dyes that contain alkylthio-substituted thiophenes with a low bandgap as a ?-conjugated bridge unit were designed and synthesized for organic dye-sensitized solar cells (DSSCs). The effects of the structural differences in terms of the position, number, and shape of the alkylthio substituents in the thiophene bridge on the photophysical properties of the dye and the photovoltaic performance of the DSSC were investigated. The introduction of an alkylthio substituent at the 3-position of thiophene led to a decrease in the degree of redshift and the value of the molar extinction coefficient of the charge-transfer band, and the substituent with a bridged structure led to a larger redshift than that of the open-chain structure. The introduction of bulky and hydrophobic side chains decreased the short-circuit photocurrent (J(sc)), which was caused by the reduced amount of dye adsorbed on TiO(2). This resulted in a decrease in the overall conversion efficiency (?), even though it could improve the open-circuit voltage (V(oc)) due to the retardation of charge recombination. Furthermore, the change in solvents for TiO(2) sensitization had a critical effect on the performance of the resulting DSSCs due to the different amounts of dye adsorbed. Based on the optimized dye bath and molecular structure, the ethylene dithio-substituted dye (ATT3) showed a prominent solar-to-electricity conversion efficiency of 5.20%. PMID:22623408

Sakong, Chun; Kim, Se Hun; Yuk, Sim Bum; Namgoong, Jin Woong; Park, Se Woong; Ko, Min Jae; Kim, Dong Hoe; Hong, Kug Sun; Kim, Jae Pil

2012-08-01

300

Electronic and optical properties of dye-sensitized TiO? interfaces.  

PubMed

Dye-sensitized solar cells (DSCs) represent a promising approach to the direct conversion of sunlight to electrical energy at low cost and high efficiency. DSCs are based on a film of anatase TiO? nanoparticles covered by adsorbed molecular dyes and immersed in a liquid redox electrolyte. Upon photoexcitation of the chemisorbed dye, electrons are injected into the TiO? conduction band and can travel across the nanostructured film to reach the counter-electrode, while the oxidized dye is regenerated by the redox electrolyte. In this review we present a summary of recent computational studies of the electronic and optical properties of dye-sensitized TiO2 interfaces, with the aim of providing the basic understanding of the operation principles of DSCs and establishing the conceptual basis for their design and optimization.We start with a discussion of isolated dyes in solution, focusing on the dye's atomic structure, ground and excited state oxidation potentials, and optical absorption spectra. We examine both Ru(II)-polypyridyl complexes and organic "push-pull" dyes with a D-?-A structure, where the donor group (D) is an electron-rich unit, linked through a conjugated linker (?) to the electron-acceptor group (A). We show that a properly calibrated computational approach based on Density Functional Theory (DFT) combined with Time Dependent DFT (TD-DFT) can provide a good description of both the absorption spectra and ground and excited state oxidation potential values of the Ru(II) complexes. On the other hand, organic push-pull dyes are not well described by the standard DFT/TD-DFT approach. For these dyes, an excellent description of the electronic structure in gas phase can be obtained by the many body perturbation theory GW method, which has, however, a much higher computational cost.We next consider interacting dye/semiconductor systems. Key properties are the dye adsorption structure onto the semiconductor, the nature and localization of the dye@semiconductor excited states, and the alignment of ground and excited state energy levels at the dye/semiconductor heterointerface. These properties, along with an estimate of the electronic coupling, constitute the fundamental parameters that determine the electron injection and dye regeneration processes. For metallorganic dyes, standard DFT/TDDFT methods are again found to reproduce accurately most of the relevant electronic and optical properties. For highly conjugated organic dyes, characterized by a high degree of charge transfer excited states, instead, the problems associated to the charge-transfer nature of their excited states extend to their interaction with TiO? and translate into an erroneous description of the relative energetics of dye/semiconductor excited states. A full description of push-pull organic dyes/semiconductor excited states, which is essential for modeling the key process of electron injection in DSCs, still represents a challenge which should be addressed by next generation DFT or post-DFT methods. PMID:24488437

Pastore, Mariachiara; Selloni, Annabella; Fantacci, Simona; De Angelis, Filippo

2014-01-01

301

Dye Sensitized Tandem Photovoltaic Cells  

SciTech Connect

This work provided a new way to look at photoelectrochemical cells and their performance. Although thought of as low efficiency, a the internal efficiency of a 9% global efficiency dye sensitized solar cell is approximately equal to an 18% efficient silicon cell when each is compared to their useful spectral range. Other work undertaken with this contract also reported the first growth oriented titania and perovskite columns on a transparent conducting oxide. Other work has shown than significant performance enhancement in the performance of dye sensitized solar cells can be obtained through the use of coupling inverse opal photonic crystals to the nanocrystalline dye sensitized solar cell. Lastly, a quick efficient method was developed to bond titanium foils to transparent conducting oxide substrates for anodization.

Barber, Greg D.

2009-12-21

302

Single mode pulsed dye laser oscillator  

DOEpatents

A single mode pulsed dye laser oscillator is disclosed. The dye laser oscillator provides for improved power efficiency by reducing the physical dimensions of the overall laser cavity, which improves frequency selection capability. 6 figs.

Hackel, R.P.

1992-11-24

303

Single mode pulsed dye laser oscillator  

DOEpatents

A single mode pulsed dye laser oscillator is disclosed. The dye laser oscillator provides for improved power efficiency by reducing the physical dimensions of the overall laser cavity, which improves frequency selection capability.

Hackel, Richard P. (Livermore, CA)

1992-01-01

304

nanostructures for dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

Hierarchical architectures consisting of one-dimensional (1D) nanostructures are of great interest for potential use in energy and environmental applications in recent years. In this work, hierarchical tungsten oxide (WO3) has been synthesized via a facile hydrothermal route from ammonium metatungstate hydrate and implemented as photoelectrode for dye-sensitized solar cells. The urchin-like WO3 micro-patterns are constructed by self-organized nanoscale length 1D building blocks, which are single crystalline in nature, grown along (001) direction and confirm an orthorhombic crystal phase. The obtained powders were investigated by XRD, SEM, TEM and UV-Vis Spectroscopy. The photovoltaic performance of dye-sensitized solar cells based on WO3 photoanodes was investigated. With increasing the calcination temperature of the prepared nanopowders, the light-electricity conversion efficiency ( ?) was increased. The results were attributed to increase the crystallinity of the particles and ease of electron movement. The DSSC based on hierarchical WO3 showed a short-circuit current, an open-circuit voltage, a fill factor, and a conversion efficiency of 4.241 mA/cm2, 0.656 V, 66.74, and 1.85 %, respectively.

Rashad, M. M.; Shalan, A. E.

2014-08-01

305

Wet oxidation of high-concentration reactive dyes  

SciTech Connect

Advanced oxidation methods were used to degrade reactive dyes at high concentrations in aqueous solutions. Wet peroxide oxidation (WPO) was found to be the best method in terms of the removal of color and total organic carbon (TOC). Reactive blue (Basilen Brilliant Blue P-3R) was chosen as a model dye for determining the suitable reaction conditions. The variables studied include reaction temperature, H{sub 2}O{sub 2} dosage, solution pH, dye concentration, and catalyst usage. The removal of TOC and color by wet oxidation is very sensitive to the reaction temperature. At 150 C, the removal of 77% TOC and 90% color was obtained in less than 30 min. The initial TOC removal rate is proportional to the H{sub 2}O{sub 2} dosage. The TOC removal is insignificant even when 50% of the stoichiometric amount of H{sub 2}O{sub 2} is used. No color change is observed until the dosage of H{sub 2}O{sub 2} is 100% of the stoichiometric amount. The color removal is closely related to TOC removal. When the pH of the solution is adjusted to 3.5, the dye degradation rate increases significantly. The rates of TOC and color removal are enhanced by using a Cu{sup 2+} catalyst. Another four reactive dyes, Procion Red PX-4B, Cibacron Yellow P-6GS, Cibacron Brown P-6R, and Procion Black PX-2R, were treated at 150 C using WPO. More than 80% TOC was removed from the solution in less than 15 min. The process can remove the colors of al these dyes except Procion Black PX-2R.

Chen, G.; Lei, L.; Yue, P.L. [Hong Kong Univ. of Science and Technology, Kowloon (Hong Kong). Dept. of Chemical Engineering] [Hong Kong Univ. of Science and Technology, Kowloon (Hong Kong). Dept. of Chemical Engineering

1999-05-01

306

Optical imaging of kidney cancer with novel near-infrared heptamethine carbocyanine fluorescent dyes  

PubMed Central

PURPOSE To assess the application of near-infrared (NIR) heptamethine carbocyanine dyes, IR-783 and the synthetic analog MHI-148, as optical imaging agents for rapid detection of human kidney cancer. MATERIALS AND METHODS The uptake, retention and subcellular localization of these organic dyes were investigated in cultured kidney cancer cells. Tumor specificity of dye uptake and retention was evaluated by whole-body imaging of mice bearing human kidney cancer xenografts or freshly harvested clinical kidney cancer specimens. In addition, dye accumulation at the tissue and cellular levels was confirmed by ex vivo studies with results confirmed by fluorescence imaging of the frozen tissue sections. Peripheral blood spiked with kidney cancer cells was stained to simulate the detection of circulating tumor cells. RESULTS Preferential uptake and retention of carbocyanine NIR dyes was observed in cultured human kidney cancer cells, human kidney cancer cell-spiked whole blood, human kidney cancer xenografts and freshly harvested human kidney cancer tissues compared to normal kidney epithelial cells or normal host organs. CONCLUSIONS We described a new class of NIR heptamethine carbocyanine dyes showing potential for detecting kidney cancer cells in circulating blood and kidney cancer cells in clinical specimens. NIR carbocyanine dyes can be further developed as dual modality agents for deep-tissue imaging of localized and disseminated kidney cancer in patients. PMID:23000848

Wang, Ruoxiang; Chu, Chia-Yi; Hu, Peizhen; Master, Viraj; Osunkoya, Adeboye O.; Kim, Hyung L; Zhau, Haiyen E.; Chung, Leland W. K.

2014-01-01

307

Feasibility of solar-pumped dye lasers  

NASA Technical Reports Server (NTRS)

Dye laser gains were measured at various pump-beam irradiances on a dye cell in order to evaluate the feasibility of solar pumping. Rhodamine 6G dye was considered as a candidate for the solar-pumped laser because of its high utilization of the solar spectrum and high quantum efficiency. Measurements show that a solar concentration of 20,000 is required to reach the threshold of the dye.

Lee, Ja H.; Kim, Kyung C.; Kim, Kyong H.

1987-01-01

308

Removal of dyes and industrial dye wastes by magnesium chloride  

Microsoft Academic Search

Magnesium chloride, as compared to alum and polyaluminium chloride (PAC) is a less commonly used coagulant in the field of wastewater treatment, with a cost in between alum and PAC. It has been used in this study as a coagulant to investigate the effectiveness in the chemical precipitation method for the removal of colouring matters. The colour concentration of dye

Boon Hai Tan; Tjoon Tow Teng; A. K. Mohd Omar

2000-01-01

309

Dye laser amplifier including a low turbulence, stagnation-free dye flow configuration  

DOEpatents

A large (high flow rate) dye laser amplifier in which a continuous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of for example 30 gallons/minute, a specifically designed support vessel for containing the dye cell and a screen device for insuring that the dye stream passes into the dye cell in a substantially turbulent free, stagnation-free manner. 9 figs.

Davin, J.

1992-12-01

310

Dye laser amplifier including a low turbulence, stagnation-free dye flow configuration  

DOEpatents

A large (high flow rate) dye laser amplifier in which a continuous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of for example 30 gallons/minute, a specifically designed support vessel for containing the dye cell and a screen device for insuring that the dye stream passes into the dye cell in a substantially turbulent free, stagnation-free manner.

Davin, James (Gilroy, CA)

1992-01-01

311

High-performance liquid chromatography determination of direct and temporary dyes in natural hair colourings.  

PubMed

A simple and reliable HPLC method is described for the simultaneous determination of nine direct and temporary hair dyes in hair colourings containing vegetal extracts. Detection was performed by a diode array detector and two different wavelengths, in the visible range (450 and 650 nm), were used for quantitation. The method does not involve any extraction procedure and it is sufficiently rapid and accurate for routine analyses. The method described was successfully applied to the identification of synthetic organic dyes in 13 direct and temporary hair dyeing formulations commercialized as 'natural'. PMID:9540212

Scarpi, C; Ninci, F; Centini, M; Anselmi, C

1998-02-20

312

Solvatochromism and temperature effects on the electronic absorption spectra of some azo dyes  

NASA Astrophysics Data System (ADS)

The UV-visible electronic spectra of some azo dyes have been studied. The different bands observed in the electronic spectra of the compounds in various organic solvents have been assigned to the proper electronic transitions. The solvatochromic behaviour of these compounds was investigated by studying their visible spectra in several pure and mixed organic solvents. The longer wavelength band displayed by para-nitro azo dyes is assigned to an intermolecular charge-transfer transition. The solvated H-bonding complexes formed between N, N-dimethylformamide and the para-nitro azo dyes were investigated. ? G and formation constant, the values of Kf of the molecular complexes formed in solution have been determined. The effects of increase of temperature and concentration dependent spectroscopic changes on the longer wavelength visible band of para-nitro azo dyes were also investigated.

Alizadeh, Kamal; Seyyedi, Susan; Shamsipur, Mojtaba; Rouhani, Shohreh; Haghbeen, Kamaladin

2009-10-01

313

Solvatochromism and temperature effects on the electronic absorption spectra of some azo dyes.  

PubMed

The UV-visible electronic spectra of some azo dyes have been studied. The different bands observed in the electronic spectra of the compounds in various organic solvents have been assigned to the proper electronic transitions. The solvatochromic behaviour of these compounds was investigated by studying their visible spectra in several pure and mixed organic solvents. The longer wavelength band displayed by para-nitro azo dyes is assigned to an intermolecular charge-transfer transition. The solvated H-bonding complexes formed between N,N-dimethylformamide and the para-nitro azo dyes were investigated. DeltaG and formation constant, the values of K(f) of the molecular complexes formed in solution have been determined. The effects of increase of temperature and concentration dependent spectroscopic changes on the longer wavelength visible band of para-nitro azo dyes were also investigated. PMID:19744881

Alizadeh, Kamal; Seyyedi, Susan; Shamsipur, Mojtaba; Rouhani, Shohreh; Haghbeen, Kamaladin

2009-10-15

314

In the Bag: Contact Natural Dyes  

Microsoft Academic Search

Contact dyeing is a practical alternative to the more common immersion method of natural dyeing. Contact dyeing is a very low liquor ratio method where the actual natural dyestuff is placed around and between the goods to be dyed. The dyestuff and goods are compressed into a bundle that is placed in a plastic bag and heated by using steam,

Sara J. Kadolph; Karen Diadick Casselman

2004-01-01

315

Reactive Fluorescent Dyes For Urethane Coatings  

NASA Technical Reports Server (NTRS)

Molecules of fluorescent dyes chemically bound in urethane conformal-coating materials to enable nondestructive detection of flaws in coats through inspection under ultraviolet light, according to proposal. Dye-bonding technique prevents outgassing of dyes, making coating materials suitable for use where flaw-free coats must be assured in instrumentation or other applications in which contamination by outgassing must be minimized.

Willis, Paul B.; Cuddihy, Edward F.

1991-01-01

316

PHOTOLYSIS OF SMOKE DYES ON SOILS  

EPA Science Inventory

Photolysis of an azo, a quinophthalone, and several anthraquinone smoke dyes was studied on soil surfaces. nitially, rapid photodegradation of each dye occurred, followed by a period of much slower rate of loss, indicating that the remaining fraction of the dye was photochemicall...

317

Dye laser for lidar ozonometry  

Microsoft Academic Search

Thus results have been published in Ref. 2 of observations of ozone in the lower layers of the atmosphere with the help of lidar, but the necessary measurement accuracy was not obtained due to insufficient energy of the laser pulses. A detailed analysis of the possibility of such measurements [3] has shown the need to use a dye laser with

P. A. Baranov; V. I. Kozintsev; V. N. Makarov; V. G. Nikiforov; A. N. Novoselov

1982-01-01

318

Organic Chemicals: Angels or Goblins?  

ERIC Educational Resources Information Center

Discusses some of the controversial organic chemical substances such as DDT, Red Dye No. 2, DES, Tris, Laetrile, cyclamate, and saccharin. Concludes that the use of some has to be considered on a benefit/risk ratio. (GA)

Ferguson, Lloyd N.

1978-01-01

319

Functionalization of Cloisite 30B with fluorescent dyes  

Microsoft Academic Search

An organo-montmorillonite (Cloisite 30B) was modified with fluorescent dyes to obtain photo-functional inorganicorganic complexes for real-time monitoring of polymer-clay nanocomposite processing. The photo-functionalization with 9-anthracenemethanol (anth) was tested using adsorption from solution, as well as dry and melt compounding. Rhodamine 6G Perchlorate (RhP) and Nile Blue A Perchlorate (NBAP) were adsorbed by cation exchange. XRD, TGA and spectrofluorimetry showed that

O. Raccurt; J.-Y. Charmeau; J. Duchet-Rumeau

2010-01-01

320

Dye-doped silica-based nanoparticles for bioapplications  

NASA Astrophysics Data System (ADS)

This paper presents our recent research results on synthesis and bioapplications of dye-doped silica-based nanoparticles. The dye-doped water soluble organically modified silicate (ORMOSIL) nanoparticles (NPs) with the size of 15100 nm were synthesized by modified Stber method from methyltriethoxysilane CH3Si(OCH3)3 precursor (MTEOS). Because thousands of fluorescent dye molecules are encapsulated in the silica-based matrix, the dye-doped nanoparticles are extremely bright and photostable. Their surfaces were modified with bovine serum albumin (BSA) and biocompatible chemical reagents. The highly intensive luminescent nanoparticles were combined with specific bacterial and breast cancer antigen antibodies. The antibody-conjugated nanoparticles can identify a variety of bacterium, such as Escherichia coli O157:H7, through antibodyantigen interaction and recognition. A highly sensitive breast cancer cell detection has been achieved with the anti-HER2 monoclonal antibodynanoparticles complex. These results demonstrate the potential to apply these fluorescent nanoparticles in various biodetection systems.

Nhung Tran, Hong; Nghiem, Thi Ha Lien; Thuy Duong Vu, Thi; Tan Pham, Minh; Van Nguyen, Thi; Trang Tran, Thu; Chu, Viet Ha; Thuan Tong, Kim; Thuy Tran, Thanh; Le, Thi Thanh Xuan; Brochon, Jean-Claude; Quy Nguyen, Thi; Nhung Hoang, My; Nguyen Duong, Cao; Thuy Nguyen, Thi; Hoang, Anh Tuan; Hoa Nguyen, Phuong

2013-12-01

321

Decolorization of the textile dyes by newly isolated bacterial strains.  

PubMed

Six bacterial strains with the capability of degrading textile dyes were isolated from sludge samples and mud lakes. Aeromonas hydrophila was selected and identified because it exhibited the greatest color removal from various dyes. Although A. hydrophila displayed good growth in aerobic or agitation culture (AGI culture), color removal was the best in anoxic or anaerobic culture (ANA culture). For color removal, the most suitable pH and temperature were pH 5.5-10.0 and 20-35 degrees C under anoxic culture (ANO culture). More than 90% of RED RBN was reduced in color within 8 days at a dye concentration of 3,000 mg l(-1). This strain could also decolorize the media containing a mixture of dyes within 2 days of incubation. Nitrogen sources such as yeast extract or peptone could enhance strongly the decolorization efficiency. In contrast to a nitrogen source, glucose inhibited decolorization activity because the consumed glucose was converted to organic acids that might decrease the pH of the culture medium, thus inhibiting the cell growth and decolorization activity. Decolorization appeared to proceed primarily by biological degradation. PMID:12523970

Chen, Kuo-Cheng; Wu, Jane-Yii; Liou, Dar-Jen; Hwang, Sz-Chwun John

2003-02-27

322

Electron injection dynamics in dye-sensitized semiconductor nanocrystalline films  

NASA Astrophysics Data System (ADS)

We have summarized recent ultrafast spectroscopic studies on phenomena associated with dye-sensitization of semiconductor metal oxide nanoparticles, especially TiO2 nanocrystalline film from a surface science perspective with a strong relation to mechanism of electron injection in dye-sensitized solar cells, which are attracting much interest from both viewpoints of pure science and applied science. A lot of chemical and physical processes are involved in this solar cell, such as light harvesting by molecules and nanostructures, interfacial electron transfer, charge migration in solid and electrolyte, degradation of the materials, and so on. Among them, the very primary process initiated by photoabsorption by sensitizing dye molecules; that is, electron injection from excited adsorbates into the conduction band of semiconductor metal oxides is significantly important, because this process must be 100% efficient with a minimum driving force for high current and voltage generation. We have first focused on details of experimental methods used in this research area, and then in the following Sections, have organized this review by concentrating on each parameter that influences dynamics of electron injection in dye-sensitized semiconductors. Finally we have emphasized it is important to measure actual DSSCs for the precise comparison between electron injection dynamics and device performance.

Furube, Akihiro; Katoh, Ryuzi; Hara, Kohjiro

2014-12-01

323

Anaphylaxis to annatto dye: a case report.  

PubMed

Annatto dye is an orange-yellow food coloring extracted from the seeds of the tree Bixa orellana. It is commonly used in cheeses, snack foods, beverages, and cereals. Previously reported adverse reactions associated with annatto dye have included urticaria and angioedema. We present a patient who developed urticaria, angioedema, and severe hypotension within 20 minutes following ingestion of milk and Fiber One cereal, which contained annatto dye. Subsequent skin tests to milk, wheat, and corn were negative. The patient had a strong positive skin test to annatto dye, while controls had no response. The nondialyzable fraction of annatto dye on SDS-PAGE demonstrated two protein staining bands in the range of 50 kD. Immunoblotting demonstrated patient IgE-specific for one of these bands, while controls showed no binding. Annatto dye may contain contaminating or residual seed proteins to which our patient developed IgE hypersensitivity. Annatto dye is a potential rare cause of anaphylaxis. PMID:1994783

Nish, W A; Whisman, B A; Goetz, D W; Ramirez, D A

1991-02-01

324

Vertically emitting, dye-doped polymer laser in the green (k $ 536 nm) with a second order distributed feedback  

E-print Network

optical feedback was realized by a corrugated, periodic refractive index structure [1,2], organic dyes for electron beam lithography [10] or interference photolithographic techniques [11,12] to define the one

Cunningham, Brian

325

Dyeing of Jute with Reactive Dyes: Optimisation of the Process Variables and Assessment of Colourfastness Characteristics  

NASA Astrophysics Data System (ADS)

This paper deals with the studies on the effect of dye concentration, electrolyte (common salt) concentration, dyeing time, dyeing temperature, soda ash concentration, pH of the dye solution and material to liquor ratio (MLR) on colour strength and other colour parameters after being dyed of jute fabrics with reactive dyes, namely, Turquoise blue, Lemon Yellow, Red CN colours. The dye absorption increases with increase in electrolyte (common salt) concentration, dyeing time, dyeing temperature, soda ash concentration, pH and decreases with increase of MLR. Colour fastness to wash, light and rubbing for the dyed samples has been studied and reported. It is observed that reactive dye gives overall good colour fastness to both washing and rubbing. But the light fastness has been found to be moderate only, due to the UV-light initiated fading of jute fibre itself change of the colour substrate, ie, undyed material. This colour fastness has been significantly resolved by post treatment with 1 % benzotriazole.

Samanta, A. K.; Chakraborty, Sharmistha; Guha Roy, T. K.

2012-08-01

326

Characteristics of a Broadband Dye Laser Using Pyrromethene and Rhodamine Dyes  

NASA Technical Reports Server (NTRS)

A broadband dye laser pumped by a frequency-doubled Nd:YAG laser with a full-width half-maximum (FWHM) from 592 to 610 nm was created for the use in a dual-pump broadband CARS system called WIDECARS. The desired broadband dye laser was generated with a mixture of Pyrromethene dyes as an oscillator gain medium and a spectral selective optic in the oscillator cavity. A mixture of Rhodamine dyes were used in the amplifier dye cell. To create this laser a study was performed to characterize the spectral behavior of broadband dye lasers created with Rhodamine dyes 590, 610, and 640, Pyrromethene dyes 597 and 650 as well as mixture of these dyes.

Tedder, Sarah A.; Danehy, Paul M.; Wheeler, Jeffrey L.

2011-01-01

327

SOCIAL PATH FOLLOWING Carmine Oliva  

E-print Network

of path following; each agent is now able to avoid static and dynamic obstacles along its path, to predict a specific profile for each agent, our system can also show how different stereotypes of people act in those

Karlsson, Brynjar

328

Investigation of natural dyes and ancient textiles from korea using TOF-SIMS  

NASA Astrophysics Data System (ADS)

The identification of the colorants used on ancient textiles provides a historical pathway to the understanding of the processes associated with one of the oldest of chemical technologies, namely textile dyeing. In this paper, time-of-flight secondary ion mass spectrometry (TOF-SIMS) was used to detect dyes on textiles avoiding the time-consuming and destructive extraction procedures necessary for the spectrophotometric and chromatographic methods previously used. The plant dyes investigated belong to a variety of chemical groups, which include curcumin, crocin, carthamin, purpurin, alizarin, brazilin, shikonin, and indigo. Reference textile samples were prepared with dye extracts of plants and were characterized by TOF-SIMS. TOF-SIMS spectra for the dyed textiles showed element ions from metallic mordants, specific fragment ions, and molecular ions from organic dyes. Remnant dyes on excavated textiles have also been identified using TOF-SIMS. The ancient textile sample showed the presence of indigo clearly, although the fiber itself had degraded badly. From the results, it was concluded that most of plant dyes can be identified with TOF-SIMS and it is a very promising technique for the archaeology field.

Lee, Yeonhee; Lee, Jihye; Kim, Youngsoo; Choi, Seokchan; Ham, Seung Wook; Kim, Kang-Jin

2008-12-01

329

Cell type-specific delivery of short interfering RNAs by dye-functionalised theranostic nanoparticles  

PubMed Central

Efficient delivery of short interfering RNAs reflects a prerequisite for the development of RNA interference therapeutics. Here, we describe highly specific nanoparticles, based on near infrared fluorescent polymethine dye-derived targeting moieties coupled to biodegradable polymers. The fluorescent dye, even when coupled to a nanoparticle, mimics a ligand for hepatic parenchymal uptake transporters resulting in hepatobiliary clearance of approximately 95% of the dye within 45?min. Body distribution, hepatocyte uptake and excretion into bile of the dye itself, or dye-coupled nanoparticles can be tracked by intravital microscopy or even non-invasively by multispectral optoacoustic tomography. Efficacy of delivery is demonstrated in vivo using 3-hydroxy-3-methyl-glutaryl-CoA reductase siRNA as an active payload resulting in a reduction of plasma cholesterol levels if siRNA was formulated into dye-functionalised nanoparticles. This suggests that organ-selective uptake of a near infrared dye can be efficiently transferred to theranostic nanoparticles allowing novel possibilities for personalised silencing of disease-associated genes. PMID:25470305

Press, Adrian T.; Traeger, Anja; Pietsch, Christian; Mosig, Alexander; Wagner, Michael; Clemens, Mark G.; Jbeily, Nayla; Koch, Nicole; Gottschaldt, Michael; Bzire, Nicolas; Ermolayev, Volodymyr; Ntziachristos, Vasilis; Popp, Jrgen; Kessels, Michael M.; Qualmann, Britta; Schubert, Ulrich S.; Bauer, Michael

2014-01-01

330

Cell type-specific delivery of short interfering RNAs by dye-functionalised theranostic nanoparticles  

NASA Astrophysics Data System (ADS)

Efficient delivery of short interfering RNAs reflects a prerequisite for the development of RNA interference therapeutics. Here, we describe highly specific nanoparticles, based on near infrared fluorescent polymethine dye-derived targeting moieties coupled to biodegradable polymers. The fluorescent dye, even when coupled to a nanoparticle, mimics a ligand for hepatic parenchymal uptake transporters resulting in hepatobiliary clearance of approximately 95% of the dye within 45?min. Body distribution, hepatocyte uptake and excretion into bile of the dye itself, or dye-coupled nanoparticles can be tracked by intravital microscopy or even non-invasively by multispectral optoacoustic tomography. Efficacy of delivery is demonstrated in vivo using 3-hydroxy-3-methyl-glutaryl-CoA reductase siRNA as an active payload resulting in a reduction of plasma cholesterol levels if siRNA was formulated into dye-functionalised nanoparticles. This suggests that organ-selective uptake of a near infrared dye can be efficiently transferred to theranostic nanoparticles allowing novel possibilities for personalised silencing of disease-associated genes.

Press, Adrian T.; Traeger, Anja; Pietsch, Christian; Mosig, Alexander; Wagner, Michael; Clemens, Mark G.; Jbeily, Nayla; Koch, Nicole; Gottschaldt, Michael; Bzire, Nicolas; Ermolayev, Volodymyr; Ntziachristos, Vasilis; Popp, Jrgen; Kessels, Michael M.; Qualmann, Britta; Schubert, Ulrich S.; Bauer, Michael

2014-12-01

331

Decolorization of reactive textile dyes using water falling film dielectric barrier discharge.  

PubMed

Decolorization of reactive textile dyes Reactive Black 5, Reactive Blue 52, Reactive Yellow 125 and Reactive Green 15 was studied using advanced oxidation processes (AOPs) in a non-thermal plasma reactor, based on coaxial water falling film dielectric barrier discharge (DBD). Used initial dye concentrations in the solution were 40.0 and 80.0mg/L. The effects of different initial pH of dye solutions, and addition of homogeneous catalysts (H(2)O(2), Fe(2+) and Cu(2+)) on the decolorization during subsequent recirculation of dye solution through the DBD reactor, i.e. applied energy density (45-315kJ/L) were studied. Influence of residence time was investigated over a period of 24h. Change of pH values and effect of pH adjustments of dye solution after each recirculation on the decolorization was also tested. It was found that the initial pH of dye solutions and pH adjustments of dye solution after each recirculation did not influence the decolorization. The most effective decolorization of 97% was obtained with addition of 10mM H(2)O(2) in a system of 80.0mg/L Reactive Black 5 with applied energy density of 45kJ/L, after residence time of 24h from plasma treatment. Toxicity was evaluated using the brine shrimp Artemia salina as a test organism. PMID:21703757

Doj?inovi?, Biljana P; Rogli?, Goran M; Obradovi?, Bratislav M; Kuraica, Milorad M; Kosti?, Mirjana M; Nei?, Jelena; Manojlovi?, Dragan D

2011-08-30

332

Solvatochromism and temperature effects on the electronic absorption spectra of some azo dyes  

Microsoft Academic Search

The UVvisible electronic spectra of some azo dyes have been studied. The different bands observed in the electronic spectra of the compounds in various organic solvents have been assigned to the proper electronic transitions. The solvatochromic behaviour of these compounds was investigated by studying their visible spectra in several pure and mixed organic solvents. The longer wavelength band displayed by

Kamal Alizadeh; Susan Seyyedi; Mojtaba Shamsipur; Shohreh Rouhani; Kamaladin Haghbeen

2009-01-01

333

Parallel Combinatorial Synthesis of Azo Dyes: A Combinatorial Experiment Suitable for Undergraduate Laboratories  

ERIC Educational Resources Information Center

An experiment in the parallel synthesis of azo dyes that demonstrates the concepts of structure-activity relationships and chemical diversity with vivid colors is described. It is seen that this experiment is suitable for the second-semester organic chemistry laboratory and also for the one-semester organic laboratory.

Gung, Benjamin W.; Taylor, Richard T.

2004-01-01

334

Determining the exact number of dye molecules attached to colloidal CdSe/ZnS quantum dots in Frster resonant energy transfer assemblies  

NASA Astrophysics Data System (ADS)

Semiconductor quantum dots functionalized with organic dye molecules are important tools for biological sensor applications. Energy transfer between the quantum dot and the attached dyes can be utilized for sensing. Though important, the determination of the real number of dye molecules attached per quantum dot is rather difficult. In this work, a method will be presented to determine the number of ATTO-590 dye molecules attached to CdSe/ZnS quantum dots based on time resolved spectral analysis. The energy transfer from the excited quantum dot to the attached ATTO-590 dye leads to a reduced lifetime of the quantum dot's excitons. The higher the concentration of dye molecules, the shorter the excitonic lifetime becomes. However, the number of dye molecules attached per quantum dot will vary. Therefore, for correctly explaining the decay of the luminescence upon photoexcitation of the quantum dot, it is necessary to take into account the distribution of the number of dyes attached per quantum dot. A Poisson distribution of the ATTO-590 dye molecules not only leads to excellent agreement between experimental and theoretical decay curves but also additionally yields the average number of dye molecules attached per quantum dot. In this way, the number of dyes per quantum dot can be conveniently determined.

Kaiser, Uwe; Jimenez de Aberasturi, Dorleta; Vzquez-Gonzlez, Margarita; Carrillo-Carrion, Carolina; Niebling, Tobias; Parak, Wofgang J.; Heimbrodt, Wolfram

2015-01-01

335

Batchwise dyeing of bamboo cellulose fabric with reactive dye using ultrasonic energy.  

PubMed

Bamboo is a regenerated cellulose fiber usually dyed with reactive dyes. This paper presents results of the batchwise dyeing of bamboo fabric with reactive dyes by ultrasonic (US) and conventional (CN) dyeing methods. The study was focused at comparing the two methods for dyeing results, chemicals, temperature and time, and effluent quality. Two widely used dyes, CI Reactive Black 5 (bis-sulphatoethylsulphone) and CI Reactive Red 147 (difluorochloropyrimidine) were used in the study. The US dyeing method produced around 5-6% higher color yield (K/S) in comparison to the CN dyeing method. A significant savings in terms of fixation temperature (10C) and time (15min), and amounts of salt (10g/L) and alkali (0.5-1% on mass of fiber) was realized. Moreover, the dyeing effluent showed considerable reductions in the total dissolved solids content (minimum around 29%) and in the chemical oxygen demand (minimum around 13%) for the US dyebath in comparison to the CN dyebath. The analysis of colorfastness tests demonstrated similar results by US and CN dyeing methods. A microscopic examination on the field emission scanning electron microscope revealed that the US energy did not alter the surface morphology of the bamboo fibers. It was concluded that the US dyeing of bamboo fabric produces better dyeing results and is a more economical and environmentally sustainable method as compared to CN dyeing method. PMID:25575805

Larik, Safdar Ali; Khatri, Awais; Ali, Shamshad; Kim, Seong Hun

2015-05-01

336

Dye-Sensitized Solar Cells  

NSDL National Science Digital Library

This lesson from The Lawrence Hall of Science was taught in spring 2012 and teaches students about nano and environmental technologies. Students will create "dye-sensitized solar cells (DSSC) using nano-crystalline titanium dioxide." This page includes links to the Source Articles for the Hands-on Module and Project Staff Write-ups of the Hands-on Module. Additionally, five documents provide lecture and lab materials for instructor use.

2014-06-03

337

Enzymatic decolorization of sulfonphthalein dyes  

Microsoft Academic Search

The white rot fungus (WRF) Pleurotus ostreatus produced manganese peroxidase (MnP) and manganese-independent peroxidase (MIP) activities during solid state fermentation of wheat straw, a natural lignocellulosic substrate. Most of the sulfonphthalein (SP) dyes were decolorized by MnP at pH 4.0. The higher Km for meta-cresol purple (40?M) and lower Km for ortho-cresol red (26?M) for MnP activities explained the preference

R. Shrivastava; V. Christian; B. R. M. Vyas

2005-01-01

338

Phthalocyanine dye as an extremely photostable and highly fluorescent near-infrared labeling reagent  

NASA Astrophysics Data System (ADS)

Current organic fluorophores used as labeling reagents for biomolecule conjugation have significant limitations in photostability. This compromises their performance in applications that require a photostable fluorescent reporting group. For example, in molecular imaging and single molecule microscopy, photostable fluorescent labels are important for observing and tracking individual molecular events over extended period of time. We report in this paper an extremely photostable and highly fluorescent phthalocyanine dye, IRDye TM 700DX, as a near-infrared fluorescence labeling reagent to conjugate with biomolecules. This novel water-soluble silicon phthalocyanine dye has an isomericly pure chemical structure. The dye is about 45 to 128 times more photostable than current near-IR fluorophores, e.g. Alexa Fluor"R"680, Cy TM 5.5, Cy TM 7 and IRDye TM 800CW dyes; and about 27 times more photostable than tetramethylrhodamine (TMR), one of the most photostable organic dyes. This dye also meets all the other stringent requirements as an ideal fluorophore for biomolecules labeling such as excellent water solubility, no aggregation in high ionic strength buffer, large extinction coefficient and high fluorescent quantum yield. Antibodies conjugated with IRDye TM 700DX at high D/P ratio exist as monomeric species in high ionic buffer and have bright fluorescence. The IRDye TM 700DX conjugated antibodies generate sensitive, highly specific detection with very low background in Western blot and cytoblot assays.

Peng, Xinzhan; Draney, Daniel R.; Volcheck, William M.; Bashford, Gregory R.; Lamb, Donald T.; Grone, Daniel L.; Zhang, Yonghong; Johnson, Craig M.

2006-02-01

339

Dye laser traveling wave amplifier  

NASA Technical Reports Server (NTRS)

Injection locking was applied to a cavity-dumped coaxial flashlamp pumped dye laser in an effort to obtain nanosecond duration pulses which have both high energy and narrow-linewidth. In the absence of an injected laser pulse, the cavity-dumped dye laser was capable of generating high energy (approx. 60mJ) nanosecond duration output pulses. These pulses, however, had a fixed center wavelength and were extremely broadband (approx. 6nm FWHM). Experimental investigations were performed to determine if the spectral properties of these outputs could be improved through the use of injection-locking techniques. A parametric study to determine the specific conditions under which the laser could be injection-locked was also carried out. Significant linewidth reduction to 0.0015nm) of the outputs was obtained through injection-locking but only at wavelengths near the peak lasing wavelength of the dye. It was found, however; that by inserting weakly dispersive tuning elements in the laser cavity, these narrow-linewidth outputs could be obtained over a wide (24nm) tuning range. Since the tuning elements had low insertion losses, the tunability of the output was obtained without sacrificing output pulse energy.

Davidson, F.; Hohman, J.

1985-01-01

340

Ultrafast distributed feedback dye lasers  

NASA Astrophysics Data System (ADS)

A distributed feedback dye laser (DFDL) was experimentally studied to determine the utmost lower limit on ultrafast pulse generation. The ultimate aim was to determine its suitability as a cheaper high peak power laser source. The dye cell was excited by the second harmonic of a laboratory built cavity dumped passively q switched and modelocked Nd:YAG Laser to induce temperature phase grating in dye solution. Different features studied include threshold conditions, pulse shortening, by reducing cavity length, polymerization limitations, simultaneous induction of multiple superimposed gratings, line narrowing, polarization, temporal and spectral characteristics. The pump polarization affect on dynamic gratings and threshold conditions indicated the number of lasing lines (maximum nine) or intensity of a single line depends upon the state of pump polarization (SOP). Various types of tuning methods such as Bragg index, refractive index, half angle and state of pump polarization were tested for improved divergence, bandwidth, line-width and wider spectral ranges. The combined effect of coherence length and SOP of excitation laser on emission of multiple lines was studied without using external gratings. The results of this critical and contemporary work on DFDL is in agreement with most of the published results and opens a new era for their potential suitability in optical communication, sensing and photonic devices.

Khan, Nasrullah

2000-04-01

341

In defence of 'dye therapy'.  

PubMed

Worldwide, healthcare is facing enormous problems with the continuing rise of drug-resistant infectious diseases. In view of the scarcity of new antimicrobial agents and the withdrawal of many pharmaceutical houses from the fray, alternative approaches are required. One of these is photoantimicrobial chemotherapy, which is highly effective across the range of microbial pathogens and does not suffer from resistance. However, there is a lack of uptake of this approach by healthcare providers and the pharmaceutical industry alike. It is seldom recalled that, unlike anticancer photodynamic therapy, the development of photoantimicrobial agents has evolved from the antiseptic 'dye therapy' in common use until the widespread introduction of the penicillin class in the mid-1940s. Cationic biological dyes such as methylene blue, crystal violet and acriflavine were effective in local wound therapy and today provide a sound basis for light-activated antimicrobial therapeutics. It is proposed that such 'safe' dyes are introduced as locally administered photoantimicrobials, especially in order to conserve valuable conventional antibacterial drugs. PMID:24795083

Wainwright, Mark

2014-07-01

342

The effect of operational parameters on the photocatalytic degradation of Congo red organic dye using ZnO-CdS core-shell nano-structure coated on glass by Doctor Blade method  

NASA Astrophysics Data System (ADS)

Photocatalytic degradation of Congo red was investigated using ZnO-CdS core-shell nano-structure coated on glass by Doctor Blade method in aqueous solution under irradiation. Field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) techniques were used for the morphological and structural characterization of ZnO-CdS core-shell nanostructures. XRD results showed diffractions of wurtzite zinc oxide core and wurtzite cadmium sulfide shell. FESEM results showed that nanoparticles are nearly hexagonal with an average diameter of about 50 nm. The effect of catalyst loading, UV-light irradiation time and solution pH on photocatalytic degradation of Congo red was studied and optimized values were obtained. Results showed that the employment of efficient photocatalyst and selection of optimal operational parameters may lead to complete decolorization of dye solutions. It was found that ZnO-CdS core-shell nano-structure is more favorable for the degradation of Congo red compare to pure ZnO or pure CdS due to lower electron hole recombination. The results showed that the photocatalytic degradation rate of Congo red is enhanced with increasing the content of ZnO up to ZnO(0.2 M)/CdS(0.075 M) which is reached 88.0% within 100 min irradiation.

Habibi, Mohammad Hossein; Rahmati, Mohammad Hossein

2015-02-01

343

Whole-cell fungal transformation of precursors into dyes  

PubMed Central

Background Chemical methods of producing dyes involve extreme temperatures and unsafe toxic compounds. Application of oxidizing enzymes obtained from fungal species, for example laccase, is an alternative to chemical synthesis of dyes. Laccase can be replaced by fungal biomass acting as a whole-cell biocatalyst with properties comparable to the isolated form of the enzyme. The application of the whole-cell system simplifies the transformation process and reduces the time required for its completion. In the present work, four fungal strains with a well-known ability to produce laccase were tested for oxidation of 17 phenolic and non-phenolic precursors into stable and non-toxic dyes. Results An agar-plate screening test of the organic precursors was carried out using four fungal strains: Trametes versicolor, Fomes fomentarius, Abortiporus biennis, and Cerrena unicolor. Out of 17 precursors, nine were transformed into coloured substances in the presence of actively growing fungal mycelium. The immobilized fungal biomass catalyzed the transformation of 1 mM benzene and naphthalene derivatives in liquid cultures yielding stable and non-toxic products with good dyeing properties. The type of fungal strain had a large influence on the absorbance of the coloured products obtained after 48-hour transformation of the selected precursors, and the most effective was Fomes fomentarius (FF25). Whole-cell transformation of AHBS (3-amino-4-hydroxybenzenesulfonic acid) into a phenoxazinone dye was carried out in four different systems: in aqueous media comprising low amounts of carbon and nitrogen source, in buffer, and in distilled water. Conclusions This study demonstrated the ability of four fungal strains belonging to the ecological type of white rot fungi to transform precursors into dyes. This paper highlights the potential of fungal biomass for replacing isolated enzymes as a cheaper industrial-grade biocatalyst for the synthesis of dyes and other commercially important products. The use of immobilized fungal biomass limits free migration of cells and facilitates their reuse in a continuous system for precursor transformation. PMID:20598166

2010-01-01

344

[Novelty of vital dyes in ophthalmic surgery].  

PubMed

The aim of this paper is to present recent developments in the area of novelty of vital dyes in intraocular surgery. The authors present the advantages and disadvantages of several vital dyes currently used in ophthalmic surgery. Vital dyes are used to allow better intraoperative visualization of both the anterior and posterior segments. Indocyanine green and trypan blue are the most frequently used and the most efficacious dyes for staining the important anatomic areas but often are associated with significant side effects. These dyes are used in cataract and vitreo-retinal surgery. Other dyes including rhodamine 6G, E68, bromophenol blue, light green and Chicago blue are still under preclinical assessment. PMID:20825072

Rejdak, Robert; Oleszczuk, Agnieszka; Ma?kowska, Anna; Kiczy?ska, Magdalena; Zagrski, Zbigniew; Zarnowski, Tomasz

2010-01-01

345

Concrete Embedded Dye-Synthesized Photovoltaic Solar Cell  

PubMed Central

This work presents the concept of a monolithic concrete-integrated dye-synthesized photovoltaic solar cell for optical-to-electrical energy conversion and on-site power generation. The transport measurements carried out in the dark revealed the presence of VOC of ~190?mV and ISC of ~9??A, induced by the electrochemical conversion of concrete-supplied ionic impurities at the electrodes. The current-voltage measurements performed under illumination at incident optical powers of ~46?mW confirmed the generation of electrical power of ~0.64??W with almost half generated via battery effect. This work presents a first step towards realizing the additional pathways to low-cost electrical power production in urban environments based on a combined use of organic dyes, nanotitania and concrete technology. PMID:24067664

Hosseini, T.; Flores-Vivian, I.; Sobolev, K.; Kouklin, N.

2013-01-01

346

Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes.  

PubMed

This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k=1.6, 2.1 and 1.910(-3)min(-1) for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (?) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100mWcm(-2), reveals highly stable DSSCs. PMID:23832227

Abdou, E M; Hafez, H S; Bakir, E; Abdel-Mottaleb, M S A

2013-11-01

347

Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes  

NASA Astrophysics Data System (ADS)

This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k = 1.6, 2.1 and 1.9 10-3 min-1 for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (?) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100 mW cm-2, reveals highly stable DSSCs.

Abdou, E. M.; Hafez, H. S.; Bakir, E.; Abdel-Mottaleb, M. S. A.

2013-11-01

348

40 CFR 721.2527 - Substituted diphenylazo dye (generic name).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Substituted diphenylazo dye (generic name). 721.2527 Section... 721.2527 Substituted diphenylazo dye (generic name). (a) Chemical substance...generically as a substituted diphenylazo dye (PMN P-95-514) is subject to...

2010-07-01

349

40 CFR 721.5915 - Polysubstituted phenylazopolysubstitutedphenyl dye.  

Code of Federal Regulations, 2010 CFR

...Polysubstituted phenylazopolysubstitutedphenyl dye. 721.5915 Section 721.5915 Protection...Polysubstituted phenylazopolysubstitutedphenyl dye. (a) Chemical substance and significant...polysubstituted phenylazopolysubstitutedphenyl dye (PMN P-93-658) is subject to...

2010-07-01

350

Color Tuning of an Acidic Blue Dye by Intercalation into the Basic Interlayer Galleries of a Poly(allylamine)/Synthetic Fluoromica  

E-print Network

conjugated system and a free sulfonate group. Introduction Many organic dyes are used in the food, cosmetics and hydroxide. For food, medical, and cosmetics applications, however, only certain acidic dyes for cosmetics, the use is strictly restricted by the Pollutant Release and Transfer Register (PRTR

351

Characterisation and spectral properties of surface adsorbed phenosafranine dye in zeolite-Y and ZSM-5: Photosensitisation of embedded nanoparticles of titanium dioxide  

Microsoft Academic Search

Synthesis, characterisation and photosensitisation of titanium dioxide nanoparticles by phenosafranine dye adsorbed on the external surfaces of microporous materials were carried out. Titanium dioxide nanoparticles were anchored on the external surface as well as encapsulated in the cavities of porous zeolites. The composite materials are characterized using powder XRD and UVvisible diffuse reflectance spectroscopy. The organic dye phenosafranine is used

S. Easwaramoorthi; P. Natarajan

2009-01-01

352

Solvent-enhanced Dye Diffusion in Polymer This-Films for OLED Application F. Pschenitzka, K. Long, and J. C. Sturm  

E-print Network

Solvent-enhanced Dye Diffusion in Polymer This-Films for OLED Application F. Pschenitzka, K. Long in polymer films for organic light-emitting diode (OLED) application is introduced. After an initial dye by 150 °C. OLEDs with 0.4% external quantum efficiency were demonstrated. The materials used

353

Theoretical evidence of multiple dye regeneration mechanisms in dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

The multiple regeneration mechanisms in dye-sensitized solar cells (DSSC), with N3 (Ru(dcbpy)2(NCS)2) as dye and I-/I3- as redox shuttle, have been studied by DFT methods. Our results show that different reaction pathways are possible within the same dye and the actual mechanism is controlled by the initial geometry of the dyeI complex. By considering the rapid interconversion between different N3I geometries, the reaction mechanism where N3I dissociates into neutral dye and Irad radical is preferred to the mechanism where N3I reacts with a second iodide.

Liu, Tao; Troisi, Alessandro

2013-05-01

354

Substitution of a hydroxamic acid anchor into the MK-2 dye for enhanced photovoltaic performance and water stability in a DSSC.  

PubMed

An efficient synthetic protocol to functionalize the cyanoacrylic acid anchoring group of commercially available MK-2 dye with a highly water-stable hydroxamate anchoring group is described. Extensive characterization of this hydroxamate-modified dye (MK-2HA) reveals that the modification does not affect its favorable optoelectronic properties. Dye-sensitized solar cells (DSSCs) prepared with the MK-2HA dye attain improved efficiency (6.9%), relative to analogously prepared devices with commercial MK-2 and N719 dyes. The hydroxamate anchoring group also contributes to significantly increased water stability, with a decrease in the rate constant for dye desorption of MK-2HA relative to MK-2 in the presence of water by as much as 37.5%. In addition, the hydroxamate-anchored dye undergoes essentially no loss in DSSC efficiency and the external quantum efficiency improves when up to 20% water is purposefully added to the electrolyte. In contrast, devices prepared with the commercial dye suffer a 50% decline in efficiency under identical conditions, with a concomitant decrease in external quantum efficiency. Collectively, our results indicate that covalent functionalization of organic dyes with hydroxamate anchoring groups is a simple and efficient approach to improving the water stability of the dye-semiconductor interface and overall device durability. PMID:24993024

Koenigsmann, C; Ripolles, T S; Brennan, B J; Negre, C F A; Koepf, M; Durrell, A C; Milot, R L; Torre, J A; Crabtree, R H; Batista, V S; Brudvig, G W; Bisquert, J; Schmuttenmaer, C A

2014-08-21

355

Effects of pH of Dyes on Characteristics of Dye-Sensitized Solar Cells  

NASA Astrophysics Data System (ADS)

Dye-sensitized solar cells were fabricated using natural dyes and synthesized dyes in which rear metal was not contained. Effects of pH of dyes on the characteristics of the dye-sensitized solar cells were also examined. As a result, it was found that the conversion efficiency of the dye-sensitized solar cell fabricated using red-cabbage dye with a pH of 2.5 was 0.10 point larger than that of the solar cell fabricated using red-cabbage dye with a pH of 4.0. It was also found that the conversion efficiency of the solar cell fabricated using red-perilla dye with a pH of 3.1 was 0.10 point larger than that of the solar cell fabricated using red-perilla dye with a pH of 5.8. The results are discussed on the bases of the molecular structure of mainly contained dye and the optical absorption spectra.

Furukawa, Shoji; Iino, Hiroshi; Kukita, Koudai; Kaminosono, Kaoru

356

Fluorene-based sensitizers with a phenothiazine donor: effect of mode of donor tethering on the performance of dye-sensitized solar cells.  

PubMed

Two types of fluorene-based organic dyes featuring T-shape/rod-shape molecular configuration with phenothiazine donor and cyanoacrylic acid acceptor have been synthesized and characterized as sensitizers for dye-sensitized solar cells. Phenothiazine is functionalized at either nitrogen (N10) or carbon (C3) to obtain T-shape and rod-like organic dyes, respectively. The effect of structural alternation on the optical, electrochemical, and the photovoltaic properties is investigated. The crystal structure determination of the dye containing phenyl linker revealed cofacial slip-stack columnar packing of the molecules. The trends in the optical properties of the dyes are interpreted using time-dependent density functional theory (TDDFT) computations. The rod-shaped dyes exhibited longer wavelength absorption and low oxidation potentials when compared to the corresponding T-shaped dyes attributable to the favorable electronic overlap between the phenothiazine unit and the rest of the molecule in the former dyes. However, the T-shaped dyes showed better photovoltaic properties due to the lowest unoccupied molecular orbital (LUMO) energy level favorable for electron injection into the conduction band of TiO2 and appropriate orientation of the phenothiazine unit rendering effective surface blocking to suppress the recombination of electrons between the electrolyte I3(-) and TiO2. The electrochemical impedance spectroscopy investigations provide further support for the variations in the electron injection and transfer kinetics due to the structural modifications. PMID:25557120

Baheti, Abhishek; Justin Thomas, K R; Li, Chun-Ting; Lee, Chuan-Pei; Ho, Kuo-Chuan

2015-02-01

357

Eco-Friendly Dyeing of Cotton with Indigo Dye By Electrochemical Method  

NASA Astrophysics Data System (ADS)

Eco-friendly dyeing of cotton was performed in two step process; (i) enzymatic pre-treatment of grey cotton fabric and (ii) Electrochemical dyeing of the pre-treated cotton fabric with indigo. The enzymatic pre-treatment was done in three methods; (i) amylase treatment only, (ii) amylase and hydrogen peroxide treatment and (iii) single bath method. The dyeing was carried out with the pre-treated cotton fabric. The reduction of indigo dye by electrochemical method was initiated by applying potential. Then the dyeing was carried out different concentrations of dye, glucose and NaOH. Conventional method of dyeing was also carried out and compared with the electrochemical method. Dyeability was measured by computer colour matching (CCM) GretagMacbeth colour eye 2180UV instrument.

Prabu, H. Gurumallesh; Sarala, K.; Babu, S. Ananda; Savitha, K. U.

2011-07-01

358

Predicting with confidence the efficiency of new dyes in dye sensitized solar cells.  

PubMed

We ask whether it is possible to predict the efficiency of a new dye in dye sensitized solar cells (DSSCs) on the basis of the known performance of existing dyes in the same type of device. We evaluate a number of computable predictors of the efficiency for a large set of dyes whose experimental efficiency is known. We have then used statistical regression methods to establish the relation between the predictors and the efficiency. Our predictions are associated with a rigorously determined confidence level. For a new dye of the same family we are able to predict the probability that its efficiency in a DSSC is larger than a certain threshold. This method is useful for accelerating the discovery of new dyes and establishing more rigorously the existence of specific correlations between structure and properties. Within the properties considered we find that the dye efficiency correlates more strongly with its oxidation potential and reorganization energy. PMID:25097038

Ip, Chung Man; Eleuteri, Antonio; Troisi, Alessandro

2014-09-28

359

Kinetic study of electro-Fenton oxidation of azo dyes on boron-doped diamond electrode.  

PubMed

The present work compares electrochemical degradation of red and blue azo textile dyes in single- and two-compartment electrochemical cells in the presence of Fenton reagent (Fe2+) and using a boron-doped diamond anode. Degradation of both dyes was related to the concentration of dye, applied current density and the concentration of FeSO4 catalyst. Complete colour removal and approximately 91% of organic matter oxidation was achieved in a two-compartment electrochemical cell at an applied current density of 20 mA x cm(-2), pH of 3 and Fe(2+) ion concentration of 0.02 mM. Higher current density and reaction time were required to achieve the same removals in a one-compartment electrochemical cell. Dye degradation kinetics as well as chemical oxygen demand removal rate were successfully modelled to pseudo first-order kinetics. The apparent first-order rate constants (k(o)) for degradation of red dye with an initial concentration of 20, 40 and 60 ppm were found to be 2.67 +/- 0.16, 2.19 +/- 0.09 and 1.5 +/- 0.03 min(-1), and for blue dye at the same initial concentrations were 1.99 +/- 0.2, 0.95 +/- 0.02 and 0.71 +/- 0.030 min(-1), respectively. PMID:24191481

Almomani, Fares; Baranova, Elena A

2013-01-01

360

Electrochemical decolourisation of structurally different dyes  

Microsoft Academic Search

The electrochemical decolourisation of structurally different dyes (bromophenol blue, indigo, poly R-478, phenol red, methyl orange, fuchsin, methyl green and crystal violet) by means of the application of DC electric current was assessed. It was found that the electrochemical process allowed a colour removal of all dyes studied, although the decolourisation rate largely depended on the chemical structure of the

M. A. Sanromn; M. Pazos; M. T. Ricart; C. Cameselle

2004-01-01

361

Pyronin Y (basic xanthene dye)-bentonite composite: A spectroscopic study  

NASA Astrophysics Data System (ADS)

The expansion by 1.43 Angstrom of basal spacing and the shift to higher frequencies of in-plane ring vibrations of the Pyronin Y molecule at 1603 and 1527 cm-1 on the formation of Pyronin Y-bentonite composite exhibited that the dye cations might be oriented as a monolayer form in the interlamellar spacing with aromatic rings parallel to clay layers. Thermal analysis results of this composite compared to those of raw bentonite signified the different outer sphere water entities associated with the replacement of inorganic cations with organic dye cations and the gradual decomposition of the organic molecule in the interlamellar spacing. Thermo-Infrared spectra of Pyronin Y-bentonite sample up to high temperatures showed the thermal stability of the dye-clay composite as a result of the presence of ? interactions. The pore structure characteristics of Pyronin Y-bentonite composite exhibited the increase in the number of mesopores during formation of the composite.

Tabak, A.; Kaya, M.; Yilmaz, N.; Meral, K.; Onganer, Y.; Caglar, B.; Sungur, O.

2014-02-01

362

Near Field Enhanced Photocurrent Generation in P-type Dye-Sensitized Solar Cells  

PubMed Central

Over the past few decades, the field of p-type dye-sensitized solar cell (p-DSSC) devices has undergone tremendous advances, in which Cu-based delafossite nanocrystal is of prime interest. This paper presents an augment of about 87% improvement in photocurrent observed in a particular configuration of organic dye P1 sensitized CuCrO2 delafossite nanocrystal electrode coupled with organic redox shuttle, 1-methy-1H- tetrazole-5-thiolate and its disulfide dimer when Au nanoparticles (NPs, with diameter of about 20?nm) is added into the photocathode, achieving a power convert efficiency of 0.31% (measured under standard AM 1.5?G test conditions). Detailed investigation shows that the local electrical-magnetic field effect, induced by Au NPs among the mesoporous CuCrO2 film, can improve the charge injection efficiency at dye/semiconductor interface, which is responsible for the bulk of the gain in photocurrent. PMID:24492539

Xu, Xiaobao; Cui, Jin; Han, Junbo; Zhang, Junpei; Zhang, Yibo; Luan, Lin; Alemu, Getachew; Wang, Zhong; Shen, Yan; Xiong, Dehua; Chen, Wei; Wei, Zhanhua; Yang, Shihe; Hu, Bin; Cheng, Yibing; Wang, Mingkui

2014-01-01

363

Near field enhanced photocurrent generation in p-type dye-sensitized solar cells.  

PubMed

Over the past few decades, the field of p-type dye-sensitized solar cell (p-DSSC) devices has undergone tremendous advances, in which Cu-based delafossite nanocrystal is of prime interest. This paper presents an augment of about 87% improvement in photocurrent observed in a particular configuration of organic dye P1 sensitized CuCrO2 delafossite nanocrystal electrode coupled with organic redox shuttle, 1-methy-1H- tetrazole-5-thiolate and its disulfide dimer when Au nanoparticles (NPs, with diameter of about 20?nm) is added into the photocathode, achieving a power convert efficiency of 0.31% (measured under standard AM 1.5?G test conditions). Detailed investigation shows that the local electrical-magnetic field effect, induced by Au NPs among the mesoporous CuCrO2 film, can improve the charge injection efficiency at dye/semiconductor interface, which is responsible for the bulk of the gain in photocurrent. PMID:24492539

Xu, Xiaobao; Cui, Jin; Han, Junbo; Zhang, Junpei; Zhang, Yibo; Luan, Lin; Alemu, Getachew; Wang, Zhong; Shen, Yan; Xiong, Dehua; Chen, Wei; Wei, Zhanhua; Yang, Shihe; Hu, Bin; Cheng, Yibing; Wang, Mingkui

2014-01-01

364

Near Field Enhanced Photocurrent Generation in P-type Dye-Sensitized Solar Cells  

NASA Astrophysics Data System (ADS)

Over the past few decades, the field of p-type dye-sensitized solar cell (p-DSSC) devices has undergone tremendous advances, in which Cu-based delafossite nanocrystal is of prime interest. This paper presents an augment of about 87% improvement in photocurrent observed in a particular configuration of organic dye P1 sensitized CuCrO2 delafossite nanocrystal electrode coupled with organic redox shuttle, 1-methy-1H- tetrazole-5-thiolate and its disulfide dimer when Au nanoparticles (NPs, with diameter of about 20 nm) is added into the photocathode, achieving a power convert efficiency of 0.31% (measured under standard AM 1.5 G test conditions). Detailed investigation shows that the local electrical-magnetic field effect, induced by Au NPs among the mesoporous CuCrO2 film, can improve the charge injection efficiency at dye/semiconductor interface, which is responsible for the bulk of the gain in photocurrent.

Xu, Xiaobao; Cui, Jin; Han, Junbo; Zhang, Junpei; Zhang, Yibo; Luan, Lin; Alemu, Getachew; Wang, Zhong; Shen, Yan; Xiong, Dehua; Chen, Wei; Wei, Zhanhua; Yang, Shihe; Hu, Bin; Cheng, Yibing; Wang, Mingkui

2014-02-01

365

Decolorization of Anthraquinonic Dyes from Textile Effluent Using Horseradish Peroxidase: Optimization and Kinetic Study  

PubMed Central

Two anthraquinonic dyes, C.I. Acid Blue 225 and C.I. Acid Violet 109, were used as models to explore the feasibility of using the horseradish peroxidase enzyme (HRP) in the practical decolorization of anthraquinonic dyes in wastewater. The influence of process parameters such as enzyme concentration, hydrogen peroxide concentration, temperature, dye concentration, and pH was examined. The pH and temperature activity profiles were similar for decolorization of both dyes. Under the optimal conditions, 94.7% of C.I. Acid Violet 109 from aqueous solution was decolorized (treatment time 15?min, enzyme concentration 0.15?IU/mL, hydrogen peroxide concentration 0.4?mM, dye concentration 30?mg/L, pH 4, and temperature 24C) and 89.36% of C.I. Acid Blue 225 (32?min, enzyme concentration 0.15?IU/mL, hydrogen peroxide concentration 0.04?mM, dye concentration 30?mg/L, pH 5, and temperature 24C). The mechanism of both reactions has been proven to follow the two substrate ping-pong mechanism with substrate inhibition, revealing the formation of a nonproductive or dead-end complex between dye and HRP or between H2O2 and the oxidized form of the enzyme. Both chemical oxygen demand and total organic carbon values showed that there was a reduction in toxicity after the enzymatic treatment. This study verifies the viability of use of horseradish peroxidase for the wastewaters treatment of similar anthraquinonic dyes.

ekuljica, Nataa .; Prlainovi?, Nevena .; Stefanovi?, Andrea B.; ua, Milena G.; ?i?kari?, Dragana Z.; Mijin, Duan .; Kneevi?-Jugovi?, Zorica D.

2015-01-01

366

Decolorization of anthraquinonic dyes from textile effluent using horseradish peroxidase: optimization and kinetic study.  

PubMed

Two anthraquinonic dyes, C.I. Acid Blue 225 and C.I. Acid Violet 109, were used as models to explore the feasibility of using the horseradish peroxidase enzyme (HRP) in the practical decolorization of anthraquinonic dyes in wastewater. The influence of process parameters such as enzyme concentration, hydrogen peroxide concentration, temperature, dye concentration, and pH was examined. The pH and temperature activity profiles were similar for decolorization of both dyes. Under the optimal conditions, 94.7% of C.I. Acid Violet 109 from aqueous solution was decolorized (treatment time 15?min, enzyme concentration 0.15?IU/mL, hydrogen peroxide concentration 0.4?mM, dye concentration 30?mg/L, pH 4, and temperature 24C) and 89.36% of C.I. Acid Blue 225 (32?min, enzyme concentration 0.15?IU/mL, hydrogen peroxide concentration 0.04?mM, dye concentration 30?mg/L, pH 5, and temperature 24C). The mechanism of both reactions has been proven to follow the two substrate ping-pong mechanism with substrate inhibition, revealing the formation of a nonproductive or dead-end complex between dye and HRP or between H2O2 and the oxidized form of the enzyme. Both chemical oxygen demand and total organic carbon values showed that there was a reduction in toxicity after the enzymatic treatment. This study verifies the viability of use of horseradish peroxidase for the wastewaters treatment of similar anthraquinonic dyes. PMID:25685837

ekuljica, Nataa ; Prlainovi?, Nevena ; Stefanovi?, Andrea B; ua, Milena G; ?i?kari?, Dragana Z; Mijin, Duan ; Kneevi?-Jugovi?, Zorica D

2015-01-01

367

Dye removal by surfactant encapsulated polyoxometalates.  

PubMed

A novel surfactant encapsulated polyoxometalate (SEP) has been synthesized by using a simple ion-exchange reaction. The prepared SEP complex was found to self-assemble into nanospherical particles whose morphology and component were characterized by TEM and XPS. The SEP was further incorporated into polyvinylidene fluoride (PVDF) to fabricate SEP incorporated composite membrane (SEP-M). Both the SEP and SEP-M exhibited excellent dye removal activities, which is for the first time reported as an intriguing property of the SEP. A regeneration scheme for SEP-M was successfully proposed without any loss of dye removal efficiency. Detailed mechanism studies were carried out to elucidate the nature of dye decolorization. Ion exchange was revealed to play a dominant role in the dye removal process. The current research not only renders a new example for the simple and direct synthesis of SEP but more importantly provides an efficient dye removal methodology. PMID:25194560

Yao, Lei; Lua, Shun Kuang; Zhang, Lizhi; Wang, Rong; Dong, ZhiLi

2014-09-15

368

Photophysics of xanthene dyes in surfactant solution  

NASA Astrophysics Data System (ADS)

The spectral (both absorption and fluorescence) and photoelectrochemical studies of some anionic xanthene dyes namely erythrosin B, rose bengal and eosin have been carried out in micellar solution of cationic cetyl trimethyl ammonium bromide (CTAB), anionic sodium dodecyl sulphate (SDS) and neutral triton X-100 (TX-100). The results show that all these dyes form 1:1 electron-donor-acceptor (EDA) or charge-transfer (CT) complexes with TX-100, which acts as an electron donor. There is no interaction of these dyes with SDS, whereas the interaction with CTAB is mainly electrostatic in nature. In presence of TX-100, these dyes show enhancement of fluorescence intensity with a red shift and develop photovoltage in a photoelectrochemical cell. A good correlation has been found among the photovoltage generation in the systems consisting of these dyes and TX-100, spectral shift due to complex formation and thermodynamic properties of these complexes.

Bhowmik, Benoy B.; Ganguly, Papia

2005-07-01

369

Photolysis of smoke dyes on soils  

SciTech Connect

Photolysis of an azo, a quinophthalone, and several anthraquinone smoke dyes was studied on soil surfaces. Initially, rapid photodegradation of each dye occurred, followed by a period of much slower rate of loss, indicating that the remaining fraction of the dye was photochemically protected. The average mean depths of photolysis ranged from 0.33 to 0.68 mm for outdoor studies and from 0.42 to 0.73 mm for lab studies. The magnitude of the mean depths of photolysis suggests that photo-degradation of the dyes occurs through indirect photochemical processes. Photolysis products for only two of the dyes could be identified. Photolysis of Disperse Red 9 resulted in the formation of 1-aminoanthraquinone, whereas Solvent Yellow 33 photo-degraded to give 2-carboxyquinoline and phthalic anhydride. Reaction mechanisms involving sensitized photo-oxidation by singlet oxygen are consistent with the formation of these reaction products.

Adams, R.L. (Technology Applications Inc., Athens, GA (United States). Environmental Research Lab.); Weber, E.J.; Baughman, G.L. (Environmental Protection Agency, Athens, GA (United States). Environmental Research Lab.)

1994-06-01

370

Solid-state dye-sensitized solar cells fabricated with nanoporous TiO 2 and TPD dyes: Analysis of penetration behavior and I-V characteristics  

NASA Astrophysics Data System (ADS)

We present the synthesis, electrochemical properties and device-based investigation of triphenylene diamine (TPD) sensitizer with an extended ? system consisting of donor, electron conducting and anchoring group for solid-state dye-sensitized solar cells. Solid-state dye-sensitized solar cells were fabricated using blocking TiO2 electrodes, nanoporous TiO2 electrodes and the organic hole-transporting medium, HTM (spiro-OMeTAD) in a fluorine doped tin oxide/blocking TiO2/nanoporous TiO2/TPDs/hole transport material/Au configuration. Solid state dye sensitized solar cell consisting of TPD_2 as sensitizer on mesoporous TiO2 shows the best results with a short-circuit current of 2.8 mA/cm2, an open circuit voltage of 835 mV and an overall conversion efficiency of 0.97%.

Erten-Ela, Sule; Brendel, Johannes; Thelakkat, Mukundan

2011-06-01

371

Molecular engineering of simple phenothiazine-based dyes to modulate dye aggregation, charge recombination, and dye regeneration in highly efficient dye-sensitized solar cells.  

PubMed

A series of simple phenothiazine-based dyes, namely, TP, EP, TTP, ETP, and EEP have been developed, in which the thiophene (T), ethylenedioxythiophene (E), their dimers, and mixtures are present to modulate dye aggregation, charge recombination, and dye regeneration for highly efficient dye-sensitized solar cell (DSSC) applications. Devices sensitized by the dyes TP and TTP display high power conversion efficiencies (PCEs) of 8.07 (Jsc = 15.2?mA?cm(-2), Voc =0.783?V, fill factor (FF) = 0.679) and 7.87?% (Jsc = 16.1?mA?cm(-2), Voc = 0.717?V, FF = 0.681), respectively; these were measured under simulated AM 1.5 sunlight in conjunction with the I(-)/I3(-) redox couple. By replacing the T group with the E unit, EP-based DSSCs had a slightly lower PCE of 7.98?% with a higher short-circuit photocurrent (Jsc) of 16.7?mA?cm(-2). The dye ETP, with a mixture of E and T, had an even lower PCE of 5.62?%. Specifically, the cell based on the dye EEP, with a dimer of E, had inferior Jsc and Voc values and corresponded to the lowest PCE of 2.24?%. The results indicate that the photovoltaic performance can be finely modulated through structural engineering of the dyes. The selection of T analogues as donors can not only modulate light absorption and energy levels, but also have an impact on dye aggregation and interfacial charge recombination of electrons at the interface of titania, electrolytes, and/or oxidized dye molecules; this was demonstrated through DFT calculations, electrochemical impedance analysis, and transient photovoltage studies. PMID:24715494

Hua, Yong; Chang, Shuai; He, Jian; Zhang, Caishun; Zhao, Jianzhang; Chen, Tao; Wong, Wai-Yeung; Wong, Wai-Kwok; Zhu, Xunjin

2014-05-19

372

DFT and TD-DFT study on geometries, electronic structures and electronic absorption of some metal free dye sensitizers for dye sensitized solar cells  

NASA Astrophysics Data System (ADS)

The geometries, electronic structures, polarizabilities and hyperpolarizabilities of 2-hydroxynaphthalene-1,4-dione (henna1), 3-(5-((1E)-2-(1,4-dihydro-1,4-dioxonaphthalen-3-yloxy) vinyl) thiophen-2-yl)-2-isocyanoacrylic acid (henna2) and anthocyanin dye sensitizers were studied based on density functional theory (DFT) using the hybrid functional B3LYP. The Ultraviolet-Visible (UV-Vis) spectrum was investigated by using a hybrid method which combines the properties and dynamics of many-body in the presence of time-dependent (TD) potentials, i.e. TDSCF-DFT (B3LYP). Features of the electronic absorption spectrum in the visible and near-UV regions were plotted and assigned based on TD-DFT calculations. Due to the absorption, bands of the metal-organic compound are n ? ?* present. The calculated results suggest that the three lowest energy excited states of the investigated dye sensitizers are due to photoinduced electron transfer processes. The interfacial electron transfer between semiconductor TiO2 electrode and dye sensitizer is owing to an electron injection process from excited dye to the semiconductor's conduction band. The role of linking the henna1 dye with a carboxylic acid via a thiophene bridge was analyzed. The results are that using a stronger ?-conjugate bridge as well as a strong donator and acceptor group enhances the efficiency.

Mohr, T.; Aroulmoji, V.; Ravindran, R. Samson; Mller, M.; Ranjitha, S.; Rajarajan, G.; Anbarasan, P. M.

2015-01-01

373

Application of Temperature-Dependent Fluorescent Dyes to the Measurement of Millimeter Wave Absorption in Water Applied to Biomedical Experiments  

PubMed Central

Temperature sensitivity of the fluorescence intensity of the organic dyes solutions was used for noncontact measurement of the electromagnetic millimeter wave absorption in water. By using two different dyes with opposite temperature effects, local temperature increase in the capillary that is placed inside a rectangular waveguide in which millimeter waves propagate was defined. The application of this noncontact temperature sensing is a simple and novel method to detect temperature change in small biological objects. PMID:25435859

Popenko, Oleksandr

2014-01-01

374

Electrochemical study on the TiO2 porous electrodes for metal-free dye-sensitized solar cells  

Microsoft Academic Search

Nanocrystalline TiO2 porous electrodes were prepared by screen-printing method in order to efficiently control the fabrication process. TiO2 viscous pastes were prepared from commercial TiO2 nano powder using ethyl cellulose as a porosity controlling agent. A metal-free organic dye (indoline dye D102) was used as a sensitizer. TiO2 porous electrodes with different thicknesses were investigated. The optical and physical properties

D. W. Zhang; S. Chen; X. D. Li; Z. A. Wang; J. H. Shi; Z. Sun; X. J. Yin; S. M. Huang

2009-01-01

375

Application of temperature-dependent fluorescent dyes to the measurement of millimeter wave absorption in water applied to biomedical experiments.  

PubMed

Temperature sensitivity of the fluorescence intensity of the organic dyes solutions was used for noncontact measurement of the electromagnetic millimeter wave absorption in water. By using two different dyes with opposite temperature effects, local temperature increase in the capillary that is placed inside a rectangular waveguide in which millimeter waves propagate was defined. The application of this noncontact temperature sensing is a simple and novel method to detect temperature change in small biological objects. PMID:25435859

Kuzkova, Nataliia; Popenko, Oleksandr; Yakunov, Andrey

2014-01-01

376

Multifunctional Anionic MOF Material for Dye Enrichment and Selective Sorption of C2 Hydrocarbons over Methane via Ag(+)-Exchange.  

PubMed

The anionic Zn-2,5-thiophenedicarboxylate framework material (1) built from the connection of Johnson cages can perform Ag(+)-exchange to upgrade the uptakes of C2 hydrocarbons (C2s) and separation properties of C2s over methane (C1). Moreover, its activated phase (1a) can enrich organic dyes from ethanol and make a significant red-shift in photoluminescent spectra of Rhodamine B (Rh B) via varying the aggregation states of dye molecules. PMID:25423097

Tan, Yan-Xi; Zhang, Ying; He, Yan-Ping; Zheng, Yan-Jun; Zhang, Jian

2014-12-15

377

TiO2 dye sensitized solar cell (DSSC): linear relationship of maximum power point and anthocyanin concentration  

Microsoft Academic Search

This study investigated the relationship of anthocyanin concentration from different organic fruit species and output voltage and current in a TiO2 dye-sensitized solar cell (DSSC) and hypothesized that fruits with greater anthocyanin concentration produce higher maximum power point (MPP) which would lead to higher current and voltage. Anthocyanin dye solution was made with crushing of a group of fresh fruits

Radin Ahmadian

2010-01-01

378

Effect of Electrolytes on the Decomposition of Dye by Pulsed Discharge in Air Spraying Water Droplets  

NASA Astrophysics Data System (ADS)

Effect of electrolytes on the decolorization of indigo carmine and on the production of H2O2 by pulsed discharge in air spraying water droplets was performed in sodium chloride and magnesium sulfate solutions. Peak voltage of the discharge decreased with increasing solution conductivity, but peak current and discharge energy increased. Decolorization rate and decolorization efficiency of indigo carmine and the yield of H2O2 decreased with increasing chloride and sulfate ion concentrations. It was found that the decolorization of indigo carmine and the production of H2O2 are affected by the ion concentration even in the case of discharge in air spraying water droplets. However it was less effective than that of discharge in water. Chloride ion was more effective than sulfate ion regarding the decrease of decolorization rate and the production of H2O2. Decolorization rate of indigo carmine was strongly related to the production of H2O2. These results also indicated that decolorization of indigo carmine depends on the production of hydroxyl radical.

Nose, Taisuke; Yokoyama, Yuzo; Minamitani, Yasushi

379

Interfacial Properties of a Hydrophobic Dye in the Tetrachloroethylene-Water-Glass Systems  

SciTech Connect

Interfacial effects play an important role in governing multiphase fluid behavior in porous media. Strongly hydrophobic organic dyes, used in many experimental studies to facilitate visual observation of the phase distributions, have generally been implicitly assumed to have no influence on the interfacial properties of the various phases in porous media. Sudan IV is the most commonly used dye for non-aqueous phase liquids (NAPLs) in laboratory experiments. It has also been used in at least one field experiment. The effects of this dye on the tetrachloroethylene (PCE)-water-glass system were investigated to test the assumption that the dye does not effect the interfacial properties and therefore PCE mobility. The results indicate that the dye does indeed change the interfacial relationships.The effect of the dye on the interfacial relationships is a complex function of the dye concentration, the solid phase composition, and the dynamic rate of new interface formation. The dye caused a slight (<10 percent) increase in interfacial tension at low concentrations (<0.1 g/L) and high rates of new interface formation. The dye reduced interfacial tension between PCE and water at low rates of new interface formation for all dye concentrations tested (0.00508 to 5.08 g/L). At the highest dye concentration, the PCE-water interfacial tension was significantly reduced regardless of the rate of new interface formation. The apparent interfacial tension increase at low dye concentrations is suspected to be an artifact of a low measured IFT value for the undyed PCE caused by leaching of rubber o-rings by the PCE prior to testing in the final drop-volume configuration.In addition to reducing interfacial tension, the dye was found to significantly alter the wetting relationship between PCE and water on a glass surface at and above the range of reported dye concentrations cited in the literature (1.1 to 1.7 g/L). The wetting relationship was rendered neutral from a water-wet initial condition at the highest dye concentration. The contact angle, measured through the aqueous phase, changed from 58 degrees for undyed PCE to 93 degrees at a dye concentration of 5.08 g/L. Complete reversal of the wettability is likely given the short equilibration time used in this study (approximately five minutes) together with literature indications that hundreds to thousands of hours may be required to reach equilibrium during contact angle measurements. Observations suggesting changing wetting relationships were also noted between PCE, water, and the platinum-iridium surface used in the standard du No/374y ring method for measuring interfacial tension.Observations of the dyed-PCE-water interface behavior during du No/374y ring interfacial tension measurements were similar to observations noted previously during measurements of the interfacial tension between the Savannah River Site (SRS) M-Area Settling Basin DNAPL (M-Area DNAPL) and water. This observation suggests that the M-Area DNAPL may contain surface active components. If this proves to be the case, it would have significant implications for how the M-Area DNAPL is distributed and moves in the SRS subsurface.

Tuck, D.M.

1999-02-23

380

Photosensitive Fluorescent Dye Contributes to Phototoxicity and Inflammatory Responses of Dye-doped Silica NPs in Cells and Mice  

PubMed Central

Dye-doped fluorescent silica nanoparticles provide highly intense and photostable fluorescence signals. However, some dopant dye molecules are photosensitive. A widely-used photosensitive fluorescent dopant, RuBpy, was chosen to systematically investigate the phototoxicity of the dye-doped silica nanoparticles (NPs). We investigated cell viability, DNA damage, and Reactive Oxygen Species (ROS) levels in alveolar macrophages using the dye-doped NPs with or without irradiation. Our results showed that the RuBpy-doped silica NPs could induce significant amount of ROS, DNA damage, apoptosis and impaired proliferation in MH-S cells. In vivo studies in mice showed that RuBpy-doped silica NPs induced significant inflammatory cytokine production and lowered expression in signaling proteins such as ERK1/2 and NF-?B as well as increased lung injury determined by myeloperoxidase and lipid peroxidation. Strikingly, we also found that both RuBpy alone and NPs induced systemic signaling activation in the kidney compared to the liver and lung where showed highly selective signaling patterns, which is more pronounced than RuBpy-doped silica NPs. Moreover, we discovered a critical biomarker (e.g., HMGB1) for silica NPs-induced stress and toxicity and demonstrated differentially-regulated response patterns in various organs. Our results indicate for the first time that the RuBpy-doped silica NPs may impose less inflammatory responses but stronger thermotherapeutic effects on target cells in animals than naked NPs in a time- and dose-dependent manner. PMID:24578727

Zhao, Yang; Ye, Yan; Zhou, Xikun; Chen, Jiao; Jin, Yuihui; Hanson, Aaron; Zhao, Julia Xiaojun; Wu, Min

2014-01-01

381

Hierarchically Structured Zn2SnO4 Nanobeads for High-Efficiency Dye-Sensitized Solar Cells.  

PubMed

We developed a unique strategy for fabricating hierarchically structured (nanoparticles-in-beads) Zn2SnO4 beads (ZTO-Bs), which were then used to produce ternary metal oxide-based dye-sensitized solar cells (DSSCs). DSSCs were fabricated using the ZTO-Bs as the photoelectrodes and highly absorbable organic dyes as the sensitizers. The DSSCs based on the ZTO-Bs and the organic dyes (SJ-E1 and SJ-ET1) exhibited the highest performance ever reported for DSSCs with ternary metal oxide-based photoelectrodes. The optimized DSSCs exhibited a power conversion efficiency of 6.3% (VOC of 0.71?V, JSC of 12.2?mA cm(-2), FF of 0.72), which was much higher than that for DSSCs with conventional ZTO-NPs-based photoelectrodes or those based on the popular ruthenium-based dye, N719. The unique morphology of the ZTO-Bs allowed for improvements in dye absorption, light scattering, electrolyte penetration, and the charge recombination lifetime, while the organic dyes resulted in high molar absorbability. PMID:25483243

Hwang, Daesub; Jin, Jun-Su; Lee, Horim; Kim, Hae-Jin; Chung, Heejae; Kim, Dong Young; Jang, Sung-Yeon; Kim, Dongho

2014-01-01

382

Hierarchically Structured Zn2SnO4 Nanobeads for High-Efficiency Dye-Sensitized Solar Cells  

PubMed Central

We developed a unique strategy for fabricating hierarchically structured (nanoparticles-in-beads) Zn2SnO4 beads (ZTO-Bs), which were then used to produce ternary metal oxide-based dye-sensitized solar cells (DSSCs). DSSCs were fabricated using the ZTO-Bs as the photoelectrodes and highly absorbable organic dyes as the sensitizers. The DSSCs based on the ZTO-Bs and the organic dyes (SJ-E1 and SJ-ET1) exhibited the highest performance ever reported for DSSCs with ternary metal oxide-based photoelectrodes. The optimized DSSCs exhibited a power conversion efficiency of 6.3% (VOC of 0.71?V, JSC of 12.2?mA cm?2, FF of 0.72), which was much higher than that for DSSCs with conventional ZTO-NPs-based photoelectrodes or those based on the popular ruthenium-based dye, N719. The unique morphology of the ZTO-Bs allowed for improvements in dye absorption, light scattering, electrolyte penetration, and the charge recombination lifetime, while the organic dyes resulted in high molar absorbability. PMID:25483243

Hwang, Daesub; Jin, Jun-Su; Lee, Horim; Kim, Hae-Jin; Chung, Heejae; Kim, Dong Young; Jang, Sung-Yeon; Kim, Dongho

2014-01-01

383

Hierarchically Structured Zn2SnO4 Nanobeads for High-Efficiency Dye-Sensitized Solar Cells  

NASA Astrophysics Data System (ADS)

We developed a unique strategy for fabricating hierarchically structured (nanoparticles-in-beads) Zn2SnO4 beads (ZTO-Bs), which were then used to produce ternary metal oxide-based dye-sensitized solar cells (DSSCs). DSSCs were fabricated using the ZTO-Bs as the photoelectrodes and highly absorbable organic dyes as the sensitizers. The DSSCs based on the ZTO-Bs and the organic dyes (SJ-E1 and SJ-ET1) exhibited the highest performance ever reported for DSSCs with ternary metal oxide-based photoelectrodes. The optimized DSSCs exhibited a power conversion efficiency of 6.3% (VOC of 0.71 V, JSC of 12.2 mA cm-2, FF of 0.72), which was much higher than that for DSSCs with conventional ZTO-NPs-based photoelectrodes or those based on the popular ruthenium-based dye, N719. The unique morphology of the ZTO-Bs allowed for improvements in dye absorption, light scattering, electrolyte penetration, and the charge recombination lifetime, while the organic dyes resulted in high molar absorbability.

Hwang, Daesub; Jin, Jun-Su; Lee, Horim; Kim, Hae-Jin; Chung, Heejae; Kim, Dong Young; Jang, Sung-Yeon; Kim, Dongho

2014-12-01

384

Panchromatic luminescence from julolidine dyes exhibiting excited state intramolecular proton transfer.  

PubMed

The preparation and the photophysical behaviour of novel julolidine derivatives designed for displaying excited state intramolecular proton transfer (ESIPT) are reported. These dyes exhibit panchromatic photoluminescence covering the whole visible spectral range, both in organic solvents and in the solid state. PMID:25621732

Nano, Adela; Gullo, Maria Pia; Ventura, Barbara; Armaroli, Nicola; Barbieri, Andrea; Ziessel, Raymond

2015-02-10

385

Synthesis of Triarylmethane and Xanthene Dyes Using Electrophilic Aromatic Substitution Reactions  

ERIC Educational Resources Information Center

The synthesis of dyes has long been a popular topic in organic chemistry laboratory experiments because it allows students to see first hand that reactions learned in class can be used to make compounds with useful applications. In this experiment electrophilic aromatic substitution reactions are used to synthesize several triarylmethane and

McCullagh, James V.; Daggett, Kelly A.

2007-01-01

386

Adsorption of Surfactants, Dyes and Cationic Herbicides on Sepiolite and Palygorskite  

Microsoft Academic Search

Adsorption of organic molecules, such as surfactants, dyes and cationic herbicides on sepiolite and palygorskite, is reviewed with an emphasis on modelling and applications. The experimental procedures employed in the reviewed studies included adsorption, XRD, SEM, HRTEM, FTIR, zeta potential and thermal analysis measurements. The surfactants whose adsorption and interactions with the clay minerals were studied included anionic, neutral and

Uri Shuali; Shlomo Nir; Giora Rytwo

2011-01-01

387

Hypersensitivity to contrast media and dyes.  

PubMed

This article updates current knowledge on hypersensitivity reactions to diagnostic contrast media and dyes. After application of a single iodinated radiocontrast medium (RCM), gadolinium-based contrast medium, fluorescein, or a blue dye, a hypersensitivity reaction is not a common finding; however, because of the high and still increasing frequency of those procedures, patients who have experienced severe reactions are nevertheless frequently encountered in allergy departments. Evidence on allergologic testing and management is best for iodinated RCM, limited for blue dyes, and insufficient for fluorescein. Skin tests can be helpful in the diagnosis of patients with hypersensitivity reactions to these compounds. PMID:25017677

Brockow, Knut; Snchez-Borges, Mario

2014-08-01

388

Novel aminobenzanthrone dyes for amyloid fibril detection  

NASA Astrophysics Data System (ADS)

A series of novel fluorescent aminobenzanthrone dyes have been tested for their ability to identify and characterize the oligomeric and fibrillar aggregates of lysozyme. The parameters of the dye binding to native, oligomeric and fibrillar protein have been calculated from the results of fluorimetric titration. Furthermore, several additional quantities reflecting the preference of the probe to either pre-fibrillar or fibrillar protein aggregates, have been evaluated. Based on the comparative analysis of the recovered parameters, AM4 was recommended for selective detection of protein pre-fibrillar assemblies, while the dyes AM1, AM2, AM3 were selected as the most prospective amyloid tracers.

Vus, Kateryna; Trusova, Valeriya; Gorbenko, Galyna; Kirilova, Elena; Kirilov, Georgiy; Kalnina, Inta; Kinnunen, Paavo

2012-04-01

389

Near-infrared fluorescence imaging of prostate cancer using heptamethine carbocyanine dyes  

PubMed Central

Near-infrared fluorescence (NIRF) imaging is an attractive novel modality for the detection of cancer. A previous study defined two organic polymethine cyanine dyes as ideal NIRF probes, IR-783 and its derivative MHI-148, which have excellent optical characteristics, superior biocompatibility and cancer targeting abilities. To investigate the feasibility of NIRF dye-mediated prostate cancer imaging, dye uptake and subcellular co-localization were investigated in PC-3, DU-145 and LNCaP human prostate cancer cells and RWPE-1 normal prostate epithelial cells. Different organic anion transporting peptide (OATP) inhibitors were utilized to explore the potential role of the OATP subtype, including the nonspecific OATP inhibitor bromosulfophthalein, the OATP1 inhibitor 17?-estradiol, the selective OATP1B1 inhibitor rifampicin and the selective OATP1B3 inhibitor cholecystokinin octapeptide. NIRF dyes were also used for the simulated detection of circulating tumor cells and the rapid detection of prostate cancer in human prostate cancer tissues and prostate cancer xenografts in mouse models. The results revealed that the cancer-specific uptake of these organic dyes in prostate cancer cells occurred primarily via OATP1B3. A strong NIRF signal was detected in prostate cancer tissues, but not in normal tissues that were stained with IR-783. Prostate cancer cells were recognized with particular NIR fluorescence in isolated mononuclear cell mixtures. The results of the present study demonstrated that NIRF dye-mediated imaging is a feasible and practicable method for prostate cancer detection, although further investigative studies are required before clinical translation. PMID:25354708

YUAN, JIANLIN; YI, XIAOMIN; YAN, FEI; WANG, FULI; QIN, WEIJUN; WU, GUOJUN; YANG, XIAOJIAN; SHAO, CHEN; CHUNG, LELAND W.K.

2015-01-01

390

Near?infrared fluorescence imaging of prostate cancer using heptamethine carbocyanine dyes.  

PubMed

Near?infrared fluorescence (NIRF) imaging is an attractive novel modality for the detection of cancer. A previous study defined two organic polymethine cyanine dyes as ideal NIRF probes, IR?783 and its derivative MHI?148, which have excellent optical characteristics, superior biocompatibility and cancer targeting abilities. To investigate the feasibility of NIRF dye?mediated prostate cancer imaging, dye uptake and subcellular co?localization were investigated in PC?3, DU?145 and LNCaP human prostate cancer cells and RWPE?1 normal prostate epithelial cells. Different organic anion transporting peptide(OATP) inhibitors were utilized to explore the potential role of the OATP subtype, including the nonspecific OATP inhibitor bromosulfophthalein, the OATP1 inhibitor 17??estradiol, the selective OATP1B1 inhibitor rifampicin and the selective OATP1B3 inhibitor cholecystokinin octapeptide. NIRF dyes were also used for the simulated detection of circulating tumor cells and the rapid detection of prostate cancer in human prostate cancer tissues and prostate cancer xenografts in mouse models. The results revealed that the cancer?specific uptake of these organic dyes in prostate cancer cells occurred primarily via OATP1B3. A strong NIRF signal was detected in prostate cancer tissues, but not in normal tissues that were stained with IR?783. Prostate cancer cells were recognized with particular NIR fluorescence in isolated mononuclear cell mixtures. The results of the present study demonstrated that NIRF dye?mediated imaging is a feasible and practicable method for prostate cancer detection, although further investigative studies are required before clinical translation. PMID:25354708

Yuan, Jianlin; Yi, Xiaomin; Yan, Fei; Wang, Fuli; Qin, Weijun; Wu, Guojun; Yang, Xiaojian; Shao, Chen; Chung, Leland W K

2015-02-01

391

Low-cost adsorbents for a dye uptake from contaminated water modeling of adsorption isotherms: The Langmuir, Freundlich and Elovich models  

Microsoft Academic Search

The adsorption of organic molecule to clay minerals has been reported by several investigators. Bentonite, which is made homoionics\\u000a by mono-, di- and trivalent cations was used to remove the dye, an organic molecule (Quinalizarin) used to dye cotton. Equilibrium\\u000a data were obtained by the batch technique. The results show the largest adsorption capacity of the homoionic bentonite; the\\u000a saturation

F. Ayari; E. Srasra; M. Trabelsi-Ayadi

2008-01-01

392

Tested Demonstrations: Dyeing of Anodized Aluminum.  

ERIC Educational Resources Information Center

Provides a list of needed materials, required preparations, and instructions for demonstrating the dyeing of anodized aluminum. Discusses the chemistry involved and gives equations for reactions occurring at the anode and cathode. (JM)

Gilbert, George L., Ed.

1983-01-01

393

Polymerization of novel methacrylated anthraquinone dyes  

PubMed Central

Summary A new series of polymerizable methacrylated anthraquinone dyes has been synthesized by nucleophilic aromatic substitution reactions and subsequent methacrylation. Thereby, green 5,8-bis(4-(2-methacryloxyethyl)phenylamino)-1,4-dihydroxyanthraquinone (2), blue 1,4-bis(4-((2-methacryloxyethyl)oxy)phenylamino)anthraquinone (6) and red 1-((2-methacryloxy-1,1-dimethylethyl)amino)anthraquinone (12), as well as 1-((1,3-dimethacryloxy-2-methylpropan-2-yl)amino)anthraquinone (15) were obtained. By mixing of these brilliant dyes in different ratios and concentrations, a broad color spectrum can be generated. After methacrylation, the monomeric dyes can be covalently emplaced into several copolymers. Due to two polymerizable functionalities, they can act as cross-linking agents. Thus, diffusion out of the polymer can be avoided, which increases the physiological compatibility and makes the dyes promising compounds for medical applications, such as iris implants. PMID:23503994

Dollendorf, Christian; Kreth, Susanne Katharina; Choi, Soo Whan

2013-01-01

394

Corrosion Inhibitors as Penetrant Dyes for Radiography  

NASA Technical Reports Server (NTRS)

Liquid/vapor-phase corrosion inhibitors (LVCIs) have been found to be additionally useful as penetrant dyes for neutron radiography (and perhaps also x-radiography). Enhancement of radiographic contrasts by use of LVCIs can reveal cracks, corrosion, and other defects that may be undetectable by ultrasonic inspection, that are hidden from direct optical inspection, and/or that are difficult or impossible to detect in radiographs made without dyes.

Novak, Howard L.; Hall, Phillip B.

2003-01-01

395

Novel physico-biological treatment for the remediation of textile dyes-containing industrial effluents.  

PubMed

In this work, a novel remediation strategy consisting of a sequential biological and physical process is proposed to remove dyes from a textile polluted effluent. The decolorization ability of Anoxybacillus flavithermus in an aqueous effluent containing two representative textile finishing dyes (Reactive Black 5 and Acid Black 48, as di-azo and antraquinone class, respectively) was proved. The decolorization efficiency for a mixture of both dyes reached almost 60% in less than 12h, which points out the suitability of the selected microorganism. In a sequential stage, an aqueous biphasic system consisting of non-ionic surfactants and a potassium-based organic salt, acting as the salting out agent, was investigated. The phase segregation potential of the selected salts was evaluated in the light of different thermodynamic models, and remediation levels higher than 99% were reached. PMID:23985354

lvarez, M S; Moscoso, F; Rodrguez, A; Sanromn, M A; Deive, F J

2013-10-01

396

Excellent capability in degrading azo dyes by MgZn-based metallic glass powders  

PubMed Central

The lack of new functional applications for metallic glasses hampers further development of these fascinating materials. In this letter, we report for the first time that the MgZn-based metallic glass powders have excellent functional ability in degrading azo dyes which are typical organic water pollutants. Their azo dye degradation efficiency is about 1000 times higher than that of commercial crystalline Fe powders, and 20 times higher than the Mg-Zn alloy crystalline counterparts. The high Zn content in the amorphous Mg-based alloy enables a greater corrosion resistance in water and higher reaction efficiency with azo dye compared to crystalline Mg. Even under complex environmental conditions, the MgZn-based metallic glass powders retain high reaction efficiency. Our work opens up a new opportunity for functional applications of metallic glasses. PMID:22639726

Wang, Jun-Qiang; Liu, Yan-Hui; Chen, Ming-Wei; Louzguine-Luzgin, Dmitri V.; Inoue, Akihisa; Perepezko, John H.

2012-01-01

397

Excellent capability in degrading azo dyes by MgZn-based metallic glass powders.  

PubMed

The lack of new functional applications for metallic glasses hampers further development of these fascinating materials. In this letter, we report for the first time that the MgZn-based metallic glass powders have excellent functional ability in degrading azo dyes which are typical organic water pollutants. Their azo dye degradation efficiency is about 1000 times higher than that of commercial crystalline Fe powders, and 20 times higher than the Mg-Zn alloy crystalline counterparts. The high Zn content in the amorphous Mg-based alloy enables a greater corrosion resistance in water and higher reaction efficiency with azo dye compared to crystalline Mg. Even under complex environmental conditions, the MgZn-based metallic glass powders retain high reaction efficiency. Our work opens up a new opportunity for functional applications of metallic glasses. PMID:22639726

Wang, Jun-Qiang; Liu, Yan-Hui; Chen, Ming-Wei; Louzguine-Luzgin, Dmitri V; Inoue, Akihisa; Perepezko, John H

2012-01-01

398

Coumarin-bearing triarylamine sensitizers with high molar extinction coefficient for dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

Coumarin unit is introduced into triarylamine and three organic sensitizers are designed and synthesized with triarylamine bearing coumarin moiety as the electron donor, conjugated system containing thiophene unit as the ?-bridge, and cyanoacetic acid moiety as the electron acceptor. The light-harvesting capabilities and photovoltaic performance of these dyes are investigated systematically with the comparison of different ?-bridges. High molar extinction coefficients are observed in these triarylamine dyes and the photocurrent and photovoltage are increased with the introduction of another thiophene or benzene. Optimal photovoltaic performance (? = 6.24%, Voc = 690 mV, Jsc = 14.33 mA cm-2, and ff = 0.63) is observed in the DSSC based on dye with thiophene-phenyl unit as the ?-conjugated bridge under 100 mW cm-2 simulated AM 1.5 G solar irradiation.

Zhong, Changjian; Gao, Jianrong; Cui, Yanhong; Li, Ting; Han, Liang

2015-01-01

399

Quantum chemistry calculations of 3-Phenoxyphthalonitrile dye sensitizer for solar cells.  

PubMed

The geometries, electronic structures, polarizabilities, and hyperpolarizabilities of organic dye sensitizer 3-Phenoxyphthalonitrile were studied based on Hartree-Fock (HF) and density functional theory (DFT) using the hybrid functional B3LYP. Ultraviolet-visible (UV-vis) spectrum was investigated by time dependent DFT (TD-DFT). Features of the electronic absorption spectrum in the visible and near-UV regions were assigned based on TD-DFT calculations. The absorption bands are assigned to pi-->pi* transitions. Calculated results suggest that the three excited states with the lowest excited energies in 3-Phenoxyphthalonitrile is due to photoinduced electron transfer processes. The interfacial electron transfer between semiconductor TiO(2) electrode and dye sensitizer 3-Phenoxyphthalonitrile is due to an electron injection process from excited dye to the semiconductor's conduction band. The role of phenoxy group in 3-Phenoxyphthalonitrile in geometries, electronic structures, and spectral properties were analyzed. PMID:20537937

Kumar, P Senthil; Vasudevan, K; Prakasam, A; Geetha, M; Anbarasan, P M

2010-09-15

400

Electrochemical study on the TiO2 porous electrodes for metal-free dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

Nanocrystalline TiO2 porous electrodes were prepared by screen-printing method in order to efficiently control the fabrication process. TiO2 viscous pastes were prepared from commercial TiO2 nano powder using ethyl cellulose as a porosity controlling agent. A metal-free organic dye (indoline dye D102) was used as a sensitizer. TiO2 porous electrodes with different thicknesses were investigated. The optical and physical properties of the TiO2 films, dye adsorption behavior and performance of dye-sensitized solar cells (DSCs) were investigated systemically. The electronic and ionic processes in DSCs were analysized and discussed by electrochemical impedance spectroscopy (EIS). High conversion efficiencies over 8.00 % under illumination of simulated AM1.5 sunlight (60mW/cm2) were achieved.

Zhang, D. W.; Chen, S.; Li, X. D.; Wang, Z. A.; Shi, J. H.; Sun, Z.; Yin, X. J.; Huang, S. M.

2009-08-01

401

Degradation of dyes by active species injected from a gas phase surface discharge  

NASA Astrophysics Data System (ADS)

A reactor, based on the traditional gas phase surface discharge (GPSD), is designed for degradation of dye wastewater in this study. The reactor is characterized by using the dye wastewater as a ground electrode. A spiral discharge electrode of stainless steel wire attached on the inside wall of a cylindrical insulating medium and the wastewater surrounding the insulating medium for simultaneous cooling of the discharge electrode constitute the reactor. The active chemical radicals generated by the discharge of the spiral electrode are injected into the water with the carrier gas. The removal of three organic dyes (including methyl red (MR), reactive brilliant blue (RBB) and cationic red (CR)) in aqueous solution is investigated. The effects of electrode configuration, discharge voltage and solution pH value on the decoloration efficiency of MR are discussed. The experimental results show that over 95% of decoloration efficiencies for all the dyes are obtained after several minutes of plasma treatment. 40% of chemical oxygen demand removal of MR is obtained after 8 min of discharge treatment. Furthermore, it is found that ozone mainly affects the removal of dyes and several aliphatic compounds are identified as the oxidation products of MR. The possible degradation pathways of MR by GPSD are proposed.

Li, Jie; Wang, Tiecheng; Lu, Na; Zhang, Dandan; Wu, Yan; Wang, Tianwei; Sato, Masayuki

2011-06-01

402

Voltage-Sensitive Dyes And Imaging Techniques Reveal New Patterns Of Electrical Activity In Heart Cortex  

NASA Astrophysics Data System (ADS)

Voltage-sensitive dyes bind to the plasms membrane of excitable cells (ie., muscle or nerve cells) and exhibit fluorescence and/or absorption changes that vary linearly with changes in transmembrane electrical potential. These potentiometric optical probes can be used to measure local changes in transmembrane potential by monitoring optical signals from dye molecules bound to the surface membrane. Consequently, when excitable cells are stained with such a dye and are stimulated to fire an electrical impulse (ie., an action potential (AP)), the changes in dye fluorescence have the characteristic shape and time course of APs recorded with an intracellular micro-electrode. Potentiometric dyes in conjuction with imaging techniques can now be used to visualize complex patterns and propagation of electrical activity. With photodiode arrays on video imaging techniques, patterns of biological electrical activity can be obtained with high temporal and spatial resolution which could not be obtained by conventional micro-electrodes. These methods reveal new details and offer powerful approaches to study fundamental problem in cardiac electrophysiology, communication in nerve networks, and the organization of cortical neurons.

Salama, Guy

1988-04-01

403

Efficient dye-sensitized solar cells using a tetramethylthiourea redox mediator.  

PubMed

An organic redox couple tetramethylthiourea/tetramethylformaminium disulfide (TMTU/TMFDS(2+) ) is evaluated in dye-sensitized solar cells in conjunction with a series of indoline and ruthenium-based dyes. Of these, devices with indoline dye D205 show the best performance, with an optimized power conversion efficiency of 7.6?% under AM?1.5G 1?sun illumination. Charge collection and injection are highly efficient in all TMTU-based DSCs studied. Regeneration of indoline dyes is highly efficient, whereas regeneration of ruthenium dyes by TMTU is less efficient, accounting for their inferior performance. Impedance spectroscopy results reveal that using an optimized TMTU/TMFDS(2+) electrolyte solution, the TiO2 conduction band edge is 300-400?meV lower than when an optimized I3 (-) /I(-) electrolyte is used. The would-be loss in open-circuit voltage caused by the downward conduction band shift is mostly compensated by approximately the 200?meV lower redox level of the TMTU/TMFDS(2+) electrolyte and up to 1000 times slower recombination rates. This makes TMTU/TMFDS(2+) a promising redox couple in the development of highly efficient solar energy conversion devices. PMID:23929783

Liu, Yeru; Jennings, James R; Wang, Qing

2013-11-01

404

Dye laser amplifier including a specifically designed diffuser assembly  

DOEpatents

A large (high flow rate) dye laser amplifier in which a continuous replened supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a relatively high flow rate and a specifically designed diffuser assembly for slowing down the flow of dye while, at the same time, assuring that as the dye stream flows through the diffuser assembly it does so in a stable manner.

Davin, James (Gilroy, CA); Johnston, James P. (Stanford, CA)

1992-01-01

405

Quasi Solid Polymer Electrolytes for Dye Sensitized Solar Cells  

NASA Astrophysics Data System (ADS)

Dye-sensitized solar cell (DSSC) has been considered as an alternative to the conventional silicon solar cell because of low cost, easy fabrication and relatively high conversion efficiency. A DSSC consists of a dye-sensitized nanoparticulated TiO2 electrode, an electrolyte containing redox couple and a Pt coated counter electrode. Such solar cells based on an I-/I3- redox couple in an organic solvent usually have conversion efficiencies reaching around 11%. However, a major drawback of these solution based solar cells, originally developed by Gratzel and coworkers is the lack of long-term stability due to liquid leakage, usage of volatile liquids such as acetonitrile, electrode corrosion, and photodecomposition of the dye in the solvent medium. Therefore considerable research efforts have been made in recent years to replace the liquid electrolytes with solid polymer or quasi-solid polymer (gel) electrolytes. Among these approaches, the use of gel polymer electrolytes appears to give rise to successful results in terms of conversion efficiency. Conventional poly (ethylene oxide)(PEO)-based solid polymer electrolytes exhibit poor ionic conductivities at room temperature, which is not sufficient for practical applications. Therefore, most of the recent studies have been directed to the preparation and characterization of gel polymer electrolytes which exhibit higher ionic conductivity at ambient temperature while maintain quai-solid structure. These gel polymer electrolytes prepared by incorporating a liquid electrolyte into a matrix polymer such as polyacrylonitrile(PAN), poly(vinylidene fluoride)(PVdF), poly (methyl methacrylate) (PMMA) and PEO have been employed in quasi-solid-state DSSCs to achieve power conversion efficiencies of more than 5%. Significant improvements have been achieved in recent years by modifications of the electrolytes by optimizing the ionic salt, introducing additives such as inorganic nanofillers, organic molecules and ionic liquids in order to maximize the performance of these solar cells. In this presentation, a particular attention will be drawn to the use of binary iodide mixtures in PAN based gel electrolytes to enhance the efficiency of dye-sensitized solar cells.

Dissanayake, M. A. K. Lakshman

2013-07-01

406

WASTES FROM MANUFACTURE OF DYES AND PIGMENTS. VOLUME 6. METHINE AND POLYMETHINE DYES AND PIGMENTS  

EPA Science Inventory

A preliminary study of the manufacture of methine and polymethine dyes and pigments was conducted to determine if process waste streams might contain hazardous material. The study first identifies the dyes and pigments that belong to this segment of the industry, the amounts prod...

407

WASTES FROM MANUFACTURE OF DYES AND PIGMENTS. VOLUME 3. STILBENE DYES AND FLUORESCENT BRIGHTENING AGENTS  

EPA Science Inventory

A preliminary study of the manufacture of Stilbene dyes and fluorescent brightening agents was conducted to determine if process waste streams might contain hazardous material. The study first identifies the dyes and pigments that belong to this segment of the industry, the amoun...

408

WASTES FROM MANUFACTURE OF DYES AND PIGMENTS. VOLUME 9. SULFUR DYES  

EPA Science Inventory

A preliminary study of the manufacture of sulfur dyes was conducted to determine if process waste streams might contain hazardous material. The study first identifies the dyes and pigments that belong to this segment of the industry, the amounts produced, and the known U.S. produ...

409

WASTES FROM MANUFACTURE OF DYES AND PIGMENTS. VOLUME 4. ANTHRAQUINONE DYES AND PIGMENTS  

EPA Science Inventory

A preliminary study of the manufacture of Anthraquinone dyes and pigments was conducted to determine if process waste streams might contain hazardous material. The study first identifies the dyes and pigments that belong to this segment of the industry, the amounts produced and t...

410

WASTES FROM MANUFACTURE OF DYES AND PIGMENTS. VOLUME 5. DIPHENYLMETHANE AND TRIARYLMETHANE DYES AND PIGMENTS  

EPA Science Inventory

A preliminary study of the manufacture of diphenylmethane and triarylmethane dyes was conducted to determine if process waste streams might contain hazardous material. The study first identifies the dyes and pigments that belong to this segment of the industry, the amounts produc...

411

WASTES FROM MANUFACTURE OF DYES AND PIGMENTS. VOLUME 8. PHTHALOCYANINE DYES AND PIGMENTS  

EPA Science Inventory

A preliminary study of the manufacture of phthalocyanine dyes and pigments was conducted to determine if process waste streams might contain hazardous material. The study first identifies the dyes and pigments that belong to this segment of the industry, the amounts produced, and...

412

WASTES FROM MANUFACTURE OF DYES AND PIGMENTS. VOLUME 7. XANTHENE DYES AND PIGMENTS  

EPA Science Inventory

A preliminary study of the manufacture of Xanthene dyes was conducted to determine if process waste streams might contain hazardous material. The study first identifies the dyes and pigments that belong to this segment of the industry, the amounts produced and the known U.S. prod...

413

Using the dye tracer for visualization of preferential flow in macro and micro-scale  

NASA Astrophysics Data System (ADS)

Study is focused on the visualization of the preferential flow in different soil types and their horizons using the dye tracer experiment. Study was performed in the Haplic Luvisol in Hn?v?eves and the Haplic Cambisol in Humpolec in the Czech Republic. The 100 (Haplic Luvisol) and 50 (Haplic Cambisol) liters of solute of dye Brilliant Blue FCF (5g/litr) was infiltrated on a 1 x 1 m plot (applying an initial ponding depth of 10 and 5 cm, respectively) immediately after the wheat harvest. On the next day, one half of the plot was sliced horizontally and another half vertically to study the dye distribution within the soil profile to the depth of 100 cm (macro-scale). The 3-D image of the dye distribution was created. In addition, the thin soil sections were made and micromorphological images were used to study a soil aggregate structure and dye distribution in micro-scale. The staining patterns within the vertical and horizontal sections documented very different nature of the preferential flow in different soil types and also within the soil profiles. Images of the Haplic Luvisol showed that while dye tracer was partly regularly transported and only some isolated domains were visible in the surface Ap1 horizon, the preferential flow occurred in the subsurface horizons. The preferential flow in the upper subsurface Ap2 horizon (plow pan) was caused by the gravitational biopores in the very compact matrix structure, which considerably slowed down the dye transport. In the case of deeper horizons (Bt1 and Bt2), the preferential flow occurred due to the gravitational biopores and extensively developed prismatic structure (small and very large aggregates in the Bt1 and Bt2 horizon respectively), which was highly affected by clay coatings. Even better characterization of the preferential flow particularly in these two horizons was obtained, when the same ponding dye infiltration experiment was performed directly on the top of the Bt1 horizon. Images of the Haplic Cambisol showed that the dye tracer transport in the Haplic Cambisol was in all horizons (Ap, Bw, C) mainly affected by the preferential flow caused by the gravitational fractures and biopores. The micromorphological images of the Haplic Luvisol soil samples showed higher-order aggregates of the Ap1 horizon, dense structure of the Ap2 horizon, well-developed soil structure affected by clay coatings of the Bt1 horizon and isolated pores with clay coatings inside the large aggregates of the Bt2 horizons. Aggregates in all horizons (Ap, Bw, C) of the Haplic Cambisol were poorly developed. The pore system did not show intrapedal or interpedal pores, pores were developed mainly along gravel particles. Correspondingly to the different soil structure compositions, dye tracer was differently distributed in the soil. Images did not show a regular dye distribution. It was evident that the dye was primarily distributed either in the interagregate pores and then in the pores inside the aggregates, or in the isolated large pores connected to the dye source and then into the matrix pores. Accumulated organic matter, clay coating, larger soil grains and isolated larger capillary pores, which initially did not contain the dye tracer, behaved as less-permeable or impermeable barriers. Acknowledgement: Authors acknowledge the financial support of the Grant Agency of the Czech Republic (grant No. GA CR 526/08/0434) and the Ministry of Education, Youth and Sports of the Czech Republic (grants No. 2B06095 and No. MSM 6046070901). Authors also acknowledge H.H. Gerke for his help in the field and valuable discussions.

Kodesova, Radka; Nemecek, Karel; Kodes, Vit; Fer, Miroslav; Jirku, Veronika; Nikodem, Antonin; Zigova, Anna; Jaksik, Ondrej; Kocarek, Martin

2010-05-01

414

Titania nanobundle networks as dye-sensitized solar cell photoanodes  

NASA Astrophysics Data System (ADS)

Quasi-one-dimensional (1D) titania nanobundles were synthesized via a hydrothermal method and used to print random network nanostructured films. These films are shown to be ideally suited for application as photoanodes in dye-sensitized solar cells (DSCs) as they have a higher porosity compared to the traditional 1D nanostructured TiO2 materials. Devices constructed using the N719 dye and iodide/triiodide as the redox mediator in the electrolyte yielded energy conversion efficiencies (? = 6.1 +/- 0.2%), which were marginally lower than for devices made with the commonly used P25 titania films (? = 6.3 +/- 0.1%) under one sun simulated solar radiation. Application of an electrolyte based on the [Co(bpy)3]2+/3+ redox couple and the MK2 organic sensitizer resulted in higher efficiencies (? = 7.70 +/- 0.1%) than for the P25 devices (? = 6.3 +/- 0.3%). Each performance parameter (short circuit current density, open circuit voltage and fill factor) was higher for the TiO2 nanobundle devices than those for the P25-based devices. The results of electrochemical impedance spectroscopy (EIS), intensity-modulated photovoltage spectroscopy (IMVS), and dye-loading measurements indicated that the better performance of TiO2 nanobundle devices with cobalt electrolytes correlates with higher porosity, relatively fast electron transport and more efficient suppression of electron recombination. A faster rate of diffusion of the cobalt complexes through the highly porous TiO2 nanobundle network is proposed to contribute to the enhanced device efficiency.Quasi-one-dimensional (1D) titania nanobundles were synthesized via a hydrothermal method and used to print random network nanostructured films. These films are shown to be ideally suited for application as photoanodes in dye-sensitized solar cells (DSCs) as they have a higher porosity compared to the traditional 1D nanostructured TiO2 materials. Devices constructed using the N719 dye and iodide/triiodide as the redox mediator in the electrolyte yielded energy conversion efficiencies (? = 6.1 +/- 0.2%), which were marginally lower than for devices made with the commonly used P25 titania films (? = 6.3 +/- 0.1%) under one sun simulated solar radiation. Application of an electrolyte based on the [Co(bpy)3]2+/3+ redox couple and the MK2 organic sensitizer resulted in higher efficiencies (? = 7.70 +/- 0.1%) than for the P25 devices (? = 6.3 +/- 0.3%). Each performance parameter (short circuit current density, open circuit voltage and fill factor) was higher for the TiO2 nanobundle devices than those for the P25-based devices. The results of electrochemical impedance spectroscopy (EIS), intensity-modulated photovoltage spectroscopy (IMVS), and dye-loading measurements indicated that the better performance of TiO2 nanobundle devices with cobalt electrolytes correlates with higher porosity, relatively fast electron transport and more efficient suppression of electron recombination. A faster rate of diffusion of the cobalt complexes through the highly porous TiO2 nanobundle network is proposed to contribute to the enhanced device efficiency. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr06157d

Dong, Cunku; Xiang, Wanchun; Huang, Fuzhi; Fu, Dongchuan; Huang, Wenchao; Bach, Udo; Cheng, Yi-Bing; Li, Xin; Spiccia, Leone

2014-03-01

415

Van Gieson's picrofuchsin. The staining mechanisms for collagen and cytoplasm, and an examination of the dye diffusion rate model of differential staining.  

PubMed

The staining mechanism of van Gieson's picrofuchsin was studied by use of simple protein model systems and tissue sections, and by spectrophotometry and dialysis experiments. At the endpoint of the staining reaction (equilibrium) cytoplasm is yellow. Dye dilution experiments demonstrated that the highest affinity in the tissue section--picrofuchsin system is between binding sites in cytoplasmic protein and acid fuchsin. Nevertheless sections that were first stained in acid fuchsin (AcF) and then in picrofuchsin ended up with cytoplasm stained yellow. It was concluded that differences in the dye diffusion rates and differences in the permeability of tissue components cannot be invoked to explain the differential staining result. Model experiments with dissolved proteins demonstrated a positive relationship between protein concentration and uptake of picric acid (PA) from picrofuchsin. From this and experiments with additives (sodium dodecylsulphate, urea etc.) and organic solvents, it is proposed that coagulant interchain cross-linking at the high protein concentration of the cytoplasm masks potential dye-binding sites. This affects high affinity dyes with multiple binding sites more than small dyes, and so puts AcF at a disadvantage compared to PA. Staining of non-collagen proteins is mainly by hydrophobic bonding, involving ionic attractions, apolar bonds, and release of water. This mode of binding is relatively strong, decreases swelling and leads to slow dye exchange. Dye binding to collagen is mostly by hydrogen bonds, but in aqueous dye solvent nonpolar residues and charged residues may also participate. This structure remains relatively open during and after dye-binding, and the bound dye ions are therefore easily exchanged for other dye ions. PMID:7683012

Prent, P

1993-02-01

416

Metals Verification Study for Sinclair and Dyes Inlets,Washington  

SciTech Connect

Sinclair and Dyes Inlets near Bremerton, Washington, are on the State of Washington's 1998 303(d) list of impaired waters because of fecal coliform contamination in marine water, metals in sediment and fish tissue, and organics in sediment and fish tissue. This Metals Verification Study was conducted to address the 303(d) segments that are listed for metal contaminants in marine sediment, because significant cleanup and source control activities have been conducted in the Inlets since the data supporting the 1998 303(d) listings were collected. The study was designed to obtain present-day sediment metals concentrations throughout Sinclair Inlet, Dyes Inlet, Port Orchard Passage, and Rich Passage, with stations spatially distributed to support 303(d) listing updates and also watershed-level water quality and contaminant transport modeling efforts. A total of 160 surface sediment samples from Sinclair Inlet, Dyes Inlet, Port Orchard Passage, and Rich Passage were screened for copper, lead, and zinc using X-Ray Fluorescence (XRF). 40 samples (25%) were selected for confirmatory metals analysis by ICP-MS for cadmium, silver, and arsenic in addition to copper, lead, and zinc. Regression relationships between the ICP-MS and XRF datasets were developed to estimate copper, lead, and zinc concentrations in all samples. The XRF results for copper, lead, and zinc correlated well with ICP-MS results, and predicted concentrations were calculated for all samples. The results of the Metals Verification Study show that sediment quality in Sinclair Inlet has improved markedly since implementation of cleanup and source control actions, and that the distribution of residual contaminants is limited to nearshore areas already within the actively managed Puget Sound Naval Shipyard Superfund Site where further source control actions and monitoring are under way. Outside of Sinclair Inlet, the target metals met state sediment quality standards.

Kohn, Nancy P.; Miller, Martin C.; Brandenberger, Jill M.; Johnston, Robert K.

2004-09-29

417

Titania nanobundle networks as dye-sensitized solar cell photoanodes.  

PubMed

Quasi-one-dimensional (1D) titania nanobundles were synthesized via a hydrothermal method and used to print random network nanostructured films. These films are shown to be ideally suited for application as photoanodes in dye-sensitized solar cells (DSCs) as they have a higher porosity compared to the traditional 1D nanostructured TiO2 materials. Devices constructed using the N719 dye and iodide/triiodide as the redox mediator in the electrolyte yielded energy conversion efficiencies (? = 6.1 0.2%), which were marginally lower than for devices made with the commonly used P25 titania films (? = 6.3 0.1%) under one sun simulated solar radiation. Application of an electrolyte based on the [Co(bpy)3](2+/3+) redox couple and the MK2 organic sensitizer resulted in higher efficiencies (? = 7.70 0.1%) than for the P25 devices (? = 6.3 0.3%). Each performance parameter (short circuit current density, open circuit voltage and fill factor) was higher for the TiO2 nanobundle devices than those for the P25-based devices. The results of electrochemical impedance spectroscopy (EIS), intensity-modulated photovoltage spectroscopy (IMVS), and dye-loading measurements indicated that the better performance of TiO2 nanobundle devices with cobalt electrolytes correlates with higher porosity, relatively fast electron transport and more efficient suppression of electron recombination. A faster rate of diffusion of the cobalt complexes through the highly porous TiO2 nanobundle network is proposed to contribute to the enhanced device efficiency. PMID:24567234

Dong, Cunku; Xiang, Wanchun; Huang, Fuzhi; Fu, Dongchuan; Huang, Wenchao; Bach, Udo; Cheng, Yi-Bing; Li, Xin; Spiccia, Leone

2014-04-01

418

Interactions of Monovalent Organic Cations with Pillared Clays  

Microsoft Academic Search

Interactions between an acid-activated pillared clay and several organic cations including dyes (methylene blue, MB; crystal violet, CV; acriflavin, AF) and benzyl derivatives (benzyltrimethylammonium, BTMA; benzyltriethylammonium, BTEA) were studied by adsorption measurements and X-ray diffraction. When the dyes were adsorbed from low ionic strength solutions, adsorption was irreversible but saturated at levels below the cation exchange capacity (CEC) of the

Yael Golda Mishael; Giora Rytwo; Shlomo Nir; Michel Crespin; Faiza Annabi-Bergaya; Henri Van Damme

1999-01-01

419

Unconsumed precursors and couplers after formation of oxidative hair dyes.  

PubMed

Contact allergy to hair dye ingredients, especially precursors and couplers, is a well-known entity among consumers having hair colouring done at home or at a hairdresser. The aim of the present investigation was to estimate consumer exposure to some selected precursors (p-phenylenediamine, toluene-2,5-diamine) and couplers (3-aminophenol, 4-aminophenol, resorcinol) of oxidative hair dyes during and after hair dyeing. Concentrations of unconsumed precursors and couplers in 8 hair dye formulations for non-professional use were investigated, under the conditions reflecting hair dyeing. Oxidative hair dye formation in the absence of hair was investigated using 6 products, and 2 products were used for experimental hair dyeing. In both presence and absence of hair, significant amounts of unconsumed precursors and couplers remained in the hair dye formulations after final colour development. Thus, up to 1.1% p-phenylenediamine (PPD), 0.04% toluene-2,5-diamine, 0.02% 3-aminophenol and 0.02% resorcinol were found in the hair dye formulation after the required colour was developed. The consumers are thus exposed to precursors and couplers of oxidative hair dyes, both during and after hair dyeing, when the hair is washed. Furthermore, the consumers are also expected to be exposed to intermediates of oxidative hair dyes. The allergenic potential of oxidative hair dyes as well as the intermediates of these remains unknown. PMID:16930234

Rastogi, Suresh Chandra; Ssted, Heidi; Johansen, Jeanne Duus; Menn, Torkil; Bossi, Rossana

2006-08-01

420

Natural dye extract of lawsonia inermis seed as photo sensitizer for titanium dioxide based dye sensitized solar cells  

NASA Astrophysics Data System (ADS)

Natural dye extract of lawsonia inermis seed were used as photo sensitizer to fabricate titanium dioxide nanoparticles based dye sensitized solar cells. Pure titanium dioxide (TiO2) nanoparticles in anatase phase were synthesized by sol-gel technique and pre dye treated TiO2 nanoparticles were synthesized using modified sol-gel technique by mixing lawsone pigment rich natural dye during the synthesis itself. This pre dye treatment with natural dye has yielded colored TiO2 nanoparticles with uniform adsorption of natural dye, reduced agglomeration, less dye aggregation and improved morphology. The pure and pre dye treated TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Dye sensitized solar cells (DSSC) fabricated using the pre dye treated and pure TiO2 nanoparticles sensitized by natural dye extract of lawsonia inermis seed showed a promising solar light to electron conversion efficiency of 1.47% and 1% respectively. The pre dye treated TiO2 based DSSC showed an improved efficiency of 47% when compared to that of conventional DSSC.

Ananth, S.; Vivek, P.; Arumanayagam, T.; Murugakoothan, P.

2014-07-01

421

Natural dye extract of lawsonia inermis seed as photo sensitizer for titanium dioxide based dye sensitized solar cells.  

PubMed

Natural dye extract of lawsonia inermis seed were used as photo sensitizer to fabricate titanium dioxide nanoparticles based dye sensitized solar cells. Pure titanium dioxide (TiO2) nanoparticles in anatase phase were synthesized by sol-gel technique and pre dye treated TiO2 nanoparticles were synthesized using modified sol-gel technique by mixing lawsone pigment rich natural dye during the synthesis itself. This pre dye treatment with natural dye has yielded colored TiO2 nanoparticles with uniform adsorption of natural dye, reduced agglomeration, less dye aggregation and improved morphology. The pure and pre dye treated TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Dye sensitized solar cells (DSSC) fabricated using the pre dye treated and pure TiO2 nanoparticles sensitized by natural dye extract of lawsonia inermis seed showed a promising solar light to electron conversion efficiency of 1.47% and 1% respectively. The pre dye treated TiO2 based DSSC showed an improved efficiency of 47% when compared to that of conventional DSSC. PMID:24682058

Ananth, S; Vivek, P; Arumanayagam, T; Murugakoothan, P

2014-07-15

422

Design and Syntheses of Dyes for Biological Applications  

E-print Network

The challenges in modern biological imaging applications are two-fold: (i) to develop better methods of imaging, and (ii) develop dyes that are suitable for these methods. This dissertation deals with the design and synthesis of dyes mainly...

Thivierge, Cliferson

2012-07-16

423

21 CFR 864.1850 - Dye and chemical solution stains.  

Code of Federal Regulations, 2011 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains 864.1850 Dye and chemical solution stains. (a) Identification. Dye and...

2011-04-01

424

21 CFR 864.1850 - Dye and chemical solution stains.  

Code of Federal Regulations, 2012 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains 864.1850 Dye and chemical solution stains. (a) Identification. Dye and...

2012-04-01

425

21 CFR 864.1850 - Dye and chemical solution stains.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains 864.1850 Dye and chemical solution stains. (a) Identification. Dye and...

2013-04-01

426

21 CFR 864.1850 - Dye and chemical solution stains.  

Code of Federal Regulations, 2014 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains 864.1850 Dye and chemical solution stains. (a) Identification. Dye and...

2014-04-01

427

Sorption of some textile dyes by beech wood sawdust.  

PubMed

The purpose of this paper is to establish the experimental conditions for removal of several textile dyes from aqueous solutions by sorption on beech wood sawdust, an industrial waste lignocellulosic product. From the six dyes tested, the sorbent shows preference for three dyes: Direct Brown, Direct Brown 2 and Basic Blue 86. Sorption of dyes on the beech wood sawdust is dependent on the nature of dye, pH, dyes concentration, contact time, and amount of sorbent. By comparative kinetic studies, the rate of sorption was found to conform with good correlation to pseudo-second-order kinetics. The parameters that characterize the sorption were determined on the basis of Langmuir isotherms. The preference of beech sawdust for dyes increases as follows: Basic Blue 86dye (of approximately 60% purity) was found to be 526.3 mg g(-1) for Direct Brown. PMID:18656305

Dulman, Viorica; Cucu-Man, Simona Maria

2009-03-15

428

Water-soluble benzophenoxazine dyes: syntheses, derivatization and photophysical studies  

E-print Network

quantum yields in aqueous media as compared to other reported dyes. Improved quantum yield makes these dyes attractive candidates for biological studies in aqueous media. We have also prepared alkynes and iodo derivatives of benzophenoxazines, which can...

Jose, Jiney

2007-04-25

429

Third row metal complexes as an alternative dye in dye sensitized solar cell system  

NASA Astrophysics Data System (ADS)

Copper(II), Cobalt (II) and Iron (II) complexes as photosensitizer on Dye Sensitized Solar Cell (DSSC) had been investigated. The aim of this research is to find out the respond addition of those dyes on FTO/TiO2 (FTO = fluorine Tin Oxide) thin film to visible light and the effect of various third row complexes to DSSC performance. Slip casting method was used to fabricate FTO/TiO2 and FTO/carbon thin film. The result from FTO/TiO2 UV-Vis spectra show no absorption on visible light. Dye solution was synthesized from free metal ions of Cu(II), Co(II), and Fe(II) in methanol with diphenylamine (dpa), 2,2,bypiridine (bpy), 1,10, phenathroline (phen), 4,4'-dicarboxylic acid-2,2'-bipyridine (dcbq), and anthocyanin (ant) ligands, respectively. UV-Vis spectrophotometry was used to identify FTO/TiO2/dye with various sensitizer dyes. The performance of DSSC was determined by I (current) - V (voltage) curve using Keithley 2602 A System Source. In this research, DSSCs are able to convert photon energy become electrical energy. Dye used in DSSC is greatly effect in photon to current efficiency (IPCE). The greater absorption in visible region of alternative dye used gains higher IPCE spectra. TiO2 character can help spread the absorption in whole visible region. The nanosize mesoporous TiO2 of TiO2/SiPA/CoII-PAR (SiPA = silylpropilamine) have greater value than P25 TiO2/SiPA-CoII-PAR. The SiPA/FeII-PAR and SiPA/CoII-PAR dyes are better dye than tpa.

Wahyuningsih, S.; Ramelan, A. H.; Badriyah, I.; Kristy, I. O.; Dewi, N. S.; Rahardjo, S. B.

2013-10-01

430

Biodegradation and detoxification potential of rotating biological contactor (RBC) with Irpex lacteus for remediation of dye-containing wastewater.  

PubMed

Use of fungal organisms in rotating biological contactors (RBC) for bioremediation of liquid industrial wastes has so far been limited in spite of their significant biodegradation potential. The purpose was to investigate the power of RBC using Irpex lacteus for decolorization and detoxification of industrial dyes and dyeing textile liquors. Recalcitrant dye Methylene Blue (150 mg L(-1)) was decolorized within 70 days, its mutagenicity removed, and the biological toxicity decreased more than 10-fold. I. lacteus biofilm in the RBC completely decolorized within 26 and 47 days dyeing liquors containing disperse or reactive dyes adjusted to pH4.5 and 5-fold diluted with the growth medium, respectively. Their respective biological toxicity values were reduced 10- to 10(4)-fold in dependence of the test used. A battery of toxicity tests comprising Vibrio fisheri, Lemna minor and Sinapis alba was efficient to monitor the toxicity of textile dyes and wastewaters. Strong decolorization and detoxification power of RBC using I. lacteus biofilms was demonstrated. PMID:24210510

Malachova, Katerina; Rybkova, Zuzana; Sezimova, Hana; Cerven, Jiri; Novotny, Cenek

2013-12-01

431

Efficient triarylamine-perylene dye-sensitized solar cells: influence of triple-bond insertion on charge recombination.  

PubMed

We synthesize two new metal-free donor-acceptor organic dyes (C266 and C267) featuring a N-annulated perylene block. Owing to the improved coplanarity of conjugated units as well as the prolonged conjugation upon inserting a triple bond between the triarylamine and perylene segments, the C267 dye exhibits a slightly red-shifted absorption peak and an enhanced maximum molar absorption coefficient with respect to its reference dye C266, leading to an improved photocurrent output in dye-sensitized solar cells. However, the triple-bond introduction also brings forth an over 100 mV reduced open-circuit photovoltage owing to faster interfacial charge recombination, which presents a clear correlation with a reduced mean thickness of self-assembled dye layer on titania as revealed by X-ray reflectivity measurements. The C266 dye, albeit with a relatively weaker light-harvesting capacity, displays a higher power conversion efficiency of 9.0% under the 100 mW cm(-2), simulated AM1.5G sunlight. PMID:25493711

Yan, Cancan; Ma, Wentao; Ren, Yameng; Zhang, Min; Wang, Peng

2015-01-14

432

Counterion-enhanced cyanine dye loading into lipid nano-droplets for single-particle tracking in zebrafish.  

PubMed

Superior brightness of fluorescent nanoparticles places them far ahead of the classical fluorescent dyes in the field of biological imaging. However, for in vivo applications, inorganic nanoparticles, such as quantum dots, are limited due to the lack of biodegradability. Nano-emulsions encapsulating high concentrations of organic dyes are an attractive alternative, but classical fluorescent dyes are inconvenient due to their poor solubility in the oil and their tendency to form non-fluorescent aggregates. This problem was solved here for a cationic cyanine dye (DiI) by substituting its perchlorate counterion for a bulky and hydrophobic tetraphenylborate. This new dye salt, due to its exceptional oil solubility, could be loaded at 8 wt% concentration into nano-droplets of controlled size in the range 30-90 nm. Our 90 nm droplets, which contained >10,000 cyanine molecules, were >100-fold brighter than quantum dots. This extreme brightness allowed, for the first time, single-particle tracking in the blood flow of live zebrafish embryo, revealing both the slow and fast phases of the cardiac cycle. These nano-droplets showed minimal cytotoxicity in cell culture and in the zebrafish embryo. The concept of counterion-based dye loading provides a new effective route to ultra-bright lipid nanoparticles, which enables tracking single particles in live animals, a new dimension of in vivo imaging. PMID:24661553

Kilin, Vasyl N; Anton, Halina; Anton, Nicolas; Steed, Emily; Vermot, Julien; Vandamme, Thierry F; Mely, Yves; Klymchenko, Andrey S

2014-06-01

433

A pilot plant study of the degradation of Brilliant Green dye using ozone microbubbles: mechanism and kinetics of reaction.  

PubMed

Oxidation of Brilliant Green dye was performed using ozone microbubbles in a pilot plant scale. Decolourisation was very effective at both acidic and alkaline pH. The colour of the aqueous solution was below detectable limit after 30?min at 1.7?mg/s ozone generation rate. The reaction between the dye and ozone was first-order in nature with respect to both ozone and the dye. The enhancement factor increased with increasing dye concentration. The samples were analysed by the ultra-violet-visible (UV-Vis) spectrophotometry, gas chromatography-mass spectrometry (GC-MS) and Fourier transform infra-red (FTIR) spectroscopy. From the GC-MS analysis, 13 intermediates were detected as oxidation products of this dye at various stages of oxidation. The changes in the FTIR spectra showed the destruction of the dye and the formation of new compounds. The oxidation mechanism was divided into two reaction pathways. The mineralisation of Brilliant Green was up to 80% in 60?min, as determined by total organic carbon analysis. PMID:25514135

Khuntia, Snigdha; Majumder, Subrata Kumar; Ghosh, Pallab

2015-02-01

434

Photocatalytic degradation of methyl orange dye in water solutions in the presence of MWCNT/TiO{sub 2} composites  

SciTech Connect

Highlights: ? MWCNTs/TiO{sub 2} composites were obtained to degrade organic dyes in water. ? MWCNT/TiO{sub 2} composites were analyzed by photocatalysis and structural characterization. ? The photocatalytic shows efficient method for the degradation of dyes from aqueous effluents. - Abstract: The textile and dyestuff industries are the primary sources of the release of synthetic dyes into the environment and usually there are major pollutants in dye wastewaters. Because of their toxicity and slow degradation, these dyes are categorized as environmentally hazardous materials. In this context, carbon nanotubes/TiO{sub 2} (CNTs/TiO{sub 2}) composites were prepared using multi-walled CNTs (MWCNTs), titanium (IV) propoxide and commercial TiO{sub 2} (P25{sup }) as titanium oxide sources, to degrade the methyl orange dye in solution through photocatalyst activity using UV irradiation. The composites were prepared by solution processing followed by thermal treatment at 400, 500 and 600 C. The heterojunction between nanotubes and TiO{sub 2} was confirmed by XRD, specific surface area. The coating morphology was observed with SEM and TEM.

Da Dalt, S., E-mail: silvana.da.dalt@ufrgs.br [Department of Material, Federal University of Rio Grande do Sul, Av. Osvaldo Aranha 99, Laboratory 705C, ZIP 90035-190, Porto Alegre, RS (Brazil); Alves, A.K.; Bergmann, C.P. [Department of Material, Federal University of Rio Grande do Sul, Av. Osvaldo Aranha 99, Laboratory 705C, ZIP 90035-190, Porto Alegre, RS (Brazil)

2013-05-15

435

Polymer composites containing photochromic dye solution  

NASA Astrophysics Data System (ADS)

Photochromic polymer composites were fabricated by encapsulating dye solution in a polycarbonate membrane. The membrane contained through holes of 50 nm diameter. These nanoholes provided a sufficient free volume for the dye molecules to change their structure in the photochromic isomerization process. A polymer composite containing a toluene solution of diarylethene exhibited red color when it was irradiated with violet laser, and returned to the transparent state by green laser irradiation. Another polymer composite containing spiropyran turned to blue by ultraviolet lamp irradiation and returned to the transparent state by green laser irradiation. A nonlinear input-output characteristic and a rewritable-grating function were demonstrated by using these photochromic polymers.

Saito, Mitsunori; Sakiyama, Kohei; Mochizuki, Ryosuke; Ohashi, Kenji

2010-05-01

436

Nanocarbon counterelectrode for dye sensitized solar cells  

SciTech Connect

Nanosize carbon powders were deposited on conducting glass substrate for counterelectrode application in dye sensitized solar cell (DSSC). Electrochemical impedance measurement shows that charge transfer resistance of carbon electrode in liquid electrolyte is 0.74 {omega} cm{sup -2}, which is two times less than that of screen printed platinum. Using such counterelectrode and dye sensitized TiO{sub 2} working electrode, DSSC was fabricated. Under one sun illumination (AM1.5, P{sub in} of 100 mW cm{sup -2}), carbon counterelectrode DSSC shows 6.73% overall energy conversion efficiency with good stability.

Ramasamy, Easwaramoorthi; Lee, Won Jae; Lee, Dong Yoon; Song, Jae Sung [Electric and Magnetic Devices Research Group, Korea Electrotechnology Research Institute, Changwon 641-120 (Korea, Republic of)

2007-04-23

437