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1.
Sébastien Boquel Marie‐Andrée Giguère Catherine Clark Upeksha Nanayakkara Jianhua Zhang Yvan Pelletier 《Entomologia Experimentalis et Applicata》2013,148(1):48-55
Seed potato crops are currently sprayed weekly with mineral oil to prevent transmission of the Potato virus Y (PVY; Potyviridae: Potyvirus), one of the most prevalent and important non‐persistent viruses affecting potato production. In spite of its wide usage as inhibitor of virus transmission, the mode of action for mineral oil is poorly known. The objective of this study was to quantify the effect of dosage and time from application of mineral oil on the inhibition of PVY acquisition. The bird cherry‐oat aphid, Rhopalosiphum padi (L.) (Hemiptera: Aphididae), known as vector of PVY, was used in all the experiments. The results indicated that mineral oil efficiently decreased PVY acquisition by 75 and 70% 1 day after application of 5 and 10 l ha?1, respectively. The inhibition effect decreased with time from application; mineral oil inhibits acquisition for less than 4 days at 5 l ha?1 and between 8 and 12 days at 10 l ha?1. As mineral oil was detected in the body of fewer aphids when they fed on plants 1 day after oil application, a change in the aphid probing behaviour on mineral oil‐treated plants was deduced. These results support the hypothesis that mineral oil physically inhibits the binding of the virus at the tip of the stylets. 相似文献
2.
Robert Ramage Lu Jiang Young‐Deug Kim Kevin Shaw Jin‐Li Park Hack‐Joo Kim 《Journal of peptide science》1999,5(4):195-200
2‐(4‐Nitrophenyl)sulfonylethoxycarbonyl (Nsc) is an alternative base‐labile Nα‐protecting group to 9‐fluorenylmethoxycarbonyl (Fmoc) for amino acids. The UV spectrum of the Nsc group exhibits moderate absorption at 380 nm which is excellent for real‐time monitoring of the deprotection process. It also decreases the rearrangement of X‐Asp, which can be a serious problem in SPPS. Copyright © 1999 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
3.
The 2‐(o‐nitrophenyl)‐propyl (NPP) group is used as caging group to mask the nucleobases adenine and cytosine in N‐(2‐aminoethyl)glycine peptide nucleic acids (aeg‐PNA). The adeninyl and cytosinyl nucleo amino acid building blocks Fmoc‐aNPP‐aeg‐OH and Fmoc‐cNPP‐aeg‐OH were synthesized and incorporated into PNA sequences by Fmoc solid phase synthesis relying on high stability of the NPP nucleobase protecting group toward Fmoc‐cleavage, coupling, capping, and resin cleavage conditions. Removal of the nucleobase caging group was achieved by UV‐LED irradiation at 365 nm. The nucleobase caging groups provided sterical crowding effecting the Watson–Crick base pairing, and thereby, the PNA double strand stabilities. Duplex formation can completely be suppressed for complementary PNA containing caging groups in both strands. PNA/PNA recognition can be completely restored by UV light‐triggered release of the photolabile protecting group. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
4.
Preventing aspartimide formation in Fmoc SPPS of Asp‐Gly containing peptides — practical aspects of new trialkylcarbinol based protecting groups
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In our efforts to develop a universal solution to the problem of aspartimide formation in Fmoc SPPS, we investigated the application of our new β‐trialkylmethyl protected aspartic acid building blocks to the synthesis of peptides containing the Asp‐Gly motif. The Nα‐Fmoc aspartic acid β‐tri‐(ethyl/propyl/butyl)methyl esters were used in the synthesis of the classic model peptide scorpion toxin II (VKDGYI), and their effectiveness in minimising aspartimide formation during extended piperidine treatments was evaluated. Furthermore, we compared their efficacy against that of the commonly used approach of adding acids to the Fmoc deprotection solution. Finally, we applied our aspartic acid building blocks to the stepwise Fmoc SPPS of teduglutide, a human GLP‐2 analogue, whose synthesis is made challenging by extensive aspartimide formation. In all experiments, our approach led to almost complete reduction of aspartimide formation with accompanied suppression of aspartic acid epimerisation. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
5.
P. J. T. Denusta E. G. T. de Jesus‐Ayson M. A. Laron L. M. B. Garcia 《Zeitschrift fur angewandte Ichthyologie》2014,30(3):448-453
This study determined the effect of human chorionic gonadotropin (hCG) and handling stress on the spermiation and milt response of silver perch Leiopotherapon plumbeus based on the measurement of spermatocrit, sperm density, and milt production. Compared to saline‐injected fish, the mean spermatocrit (or packed sperm) of hCG‐treated fish was significantly lower at 18 h (47.9%) and 30 h (40.2%) post‐injection while mean sperm density was significantly lower at 30 h post‐injection (3.6 × 106 cells μl?1) but not at 18 h. At 18 h (1.8 μl g‐BW?1) and 30 h (2.5 μl g‐BW?1) post‐injection, mean milt production of hCG‐treated fish was significantly higher than in the saline group. Milt consistency was also thinner in the hCG‐treated group. Mean sperm density of handled fish (18.0 × 106 cells μl?1) was significantly lower than control fish (23.4 × 106 cells μl?1). However, mean sperm density of handled plus saline‐injected (16.2 × 106 cells μl?1) and handled plus hCG‐treated fish (8.4 × 106 cells μl?1) was significantly lower than in the control goup. Having thicker milt consistency, mean spermatocrit and milt production of handled (77.5%; 1.1 μl g‐BW?1, respectively) and handled plus saline‐injected fish (75.4%; 1.1 μl g‐BW?1, respectively) were not significantly different from the control fish (76.2%; 1.3 μl g‐BW?1, respectively). Handled plus hCG‐treated fish had the lowest mean sperm density (8.4 × 106 cells μl?1) and spermatocrit (54.7%), but had the highest mean milt production (5.5 μl g‐BW?1) among the treatment groups. These results demonstrate that the hCG injection effectively induces spermiation and milt expression and that handling‐related stress negatively affects such responses. The spermatocrit method may be used to assess the spermiation and milt response of silver perch. 相似文献
6.
Base-catalyzed cleavage of the 9-fluorenylmethoxycarbonyl (FMOC) group and subsequent analysis by UV spectrophotometry is commonly employed to measure the "loading" of functional groups on solid support. Recent work suggests that 1,8-diazabicyclo[5.4. 0]undec-7-ene (DBU) may be superior to piperidine (the most commonly used base for the cleavage) for quantitative analysis by UV. We have compared deprotection of FMOC-bearing compounds by both DBU and piperidine, and have observed by GC-MS the formation of a dibenzofulvene-piperidine adduct (piperidine deprotection), and the formation of unassociated dibenzofulvene (DBU deprotection). We have further been able to use GC analysis of dibenzofulvene produced in the DBU deprotection mixture in a quantitative analysis of resin loading, which gave results comparable to UV methods. Sample preparation for this method has been automated using the Nautilus 2400 organic synthesizer to reduce the amount of operator time and increase throughput of sample analysis. Copyright 1998 John Wiley & Sons, Inc. 相似文献
7.
Progeny of the maize weevil,Sitophilus zeamais,is affected by parental exposure to clove and cinnamon essential oils
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S.M. Silva K. Haddi L.O. Viteri Jumbo E.E. Oliveira 《Entomologia Experimentalis et Applicata》2017,163(2):220-228
The interest in and utilization of botanical insecticides, particularly essential oils, has become increasingly relevant to the control of insect pests. However, the potential ecotoxicological risks or flaws (including sublethal effects on the targeted pest generation and its subsequent progeny) of this pest control tool have been neglected frequently. Here, we evaluated the effects of sublethal exposure to clove, Syzygium aromaticum (L.) Merrill & Perry (Myrtaceae), and cinnamon, Cinnamomum verum J. Presl (Lauraceae), essential oils on adult (F0) maize weevils, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), and the physiology (e.g., body mass, respirometry, and grain consumption) and population dynamics (e.g., daily emergence and sex ratio) of their progeny. Longevities of the parents were negatively affected by the essential oils in a concentration‐dependent manner. Parental sublethal exposure to clove oil (0.17 μl cm?2) accelerated offspring emergence but delayed the emergence of females compared to males. Parents that were sublethally exposed to clove (0.17 μl cm?2) or cinnamon (0.35 μl cm?2) essential oils produced heavier offspring. Parental sublethal exposure to cinnamon essential oil accelerated offspring emergence (at 0.70 μl cm?2), delayed female emergence (at 0.17 μl cm?2), and enhanced grain consumption (at 0.35 and 0.70 μl cm?2) of the progeny. Thus, our findings indicate that sublethal exposure to clove and cinnamon essential oils is capable of promoting transgenerational effects in S. zeamais that can negatively impact the control efficacy of such products. 相似文献
8.
Benzofurazan‐based fluorophore for the selective determination of flupentixol dihydrochloride: Application to content uniformity testing
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One of the most commonly used drugs in treatment of schizophrenia is flupentixol dihydrochloride, therefore it is important to develop a simple, low cost and sensitive spectrofluorimetric method for the estimation of flupentixol dihydrochloride. The yellow fluorescent product that is generated from the nucleophilic substitution reaction of the free lone pair of the alcoholic hydroxyl group of the drug and 4‐chloro‐7‐nitrobenzofurazan (NBD‐Cl) in Mcllvaine buffer pH 7.0 was estimated at 510 nm (λex 460 nm). The variables that affect the development of the reaction product were explored and optimized. The linear range of this method was 0.5–2.5 μg ml?1 with a limit of quantitation equal to 0.29 μg ml?1. Our method was successfully applied for the assurance of flupentixol in tablet form with average percentage recovery of 99.08 ± 1.01% without obstruction from the basic excipients exhibits. Furthermore, our strategy was extended to study the content uniformity testing of flupentixol in Fluaxnol® tablets. 相似文献
9.
Impact of light quality on a native Louisiana Chlorella vulgaris/Leptolyngbya sp. co‐culture
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Jonathan Z. Barnett Jacob Foy Ronald Malone Kelly A. Rusch Maria Teresa Gutierrez‐Wing 《Engineering in Life Science》2017,17(6):678-685
Light effect on cultures of microalgae has been studied mainly on single species cultures. Cyanobacteria have photosynthetic pigments that can capture photons of wavelengths not available to chlorophylls. A native Louisiana microalgae (Chlorella vulgaris ) and cyanobacteria (Leptolyngbya sp.) co‐culture was used to study the effects of light quality (blue–467 nm, green–522 nm, red–640 nm and white–narrow peak at 450 nm and a broad range with a peak at 550 nm) at two irradiance levels (80 and 400 μmol m?2 s?1) on the growth, species composition, biomass productivity, lipid content and chlorophyll‐a production. The co‐culture shifted from a microalgae dominant culture to a cyanobacteria culture at 80 μmol m?2 s?1. The highest growth for the cyanobacteria was observed at 80 μmol μmol m?2 s?1 and for the microalgae at 400 μmol m?2 s?1. Red light at 400 μmol m?2 s?1 had the highest growth rate (0.41 d?1), biomass (913 mg L?1) and biomass productivity (95 mg L?1 d?1). Lipid content was similar between all light colors. Green light had the highest chlorophyll‐a content (1649 μg/L). These results can be used to control the species composition of mixed cultures while maintaining their productivity. 相似文献
10.
Sap flow variation in selected riparian woodland species in the Okavango Delta,Botswana 总被引:1,自引:0,他引:1
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In the tropical Okavango Delta, transpiration by trees is an important process partly responsible for maintaining the basin as a freshwater environment. Quantification of evapotranspiration from terrestrial landforms of the delta, fringed by riparian woodlands, is one of the main contributors to uncertainty in current hydrological modelling. We investigated sap flow of common trees in the distal, mid‐ and upper delta in July–August 2012, November–December 2012 and February–April 2013 using the compensation heat pulse velocity method. In the distal delta, four Diospyros mespiliformis individuals of different sizes were studied. Four trees of different species were studied in the mid‐ and upper delta. Sap flow density (SFD; flow per unit cross‐sectional area) was used as a common unit to facilitate comparison. Sap flow varied with tree size, species, season and location. It was positively correlated with tree size (r2 = 0.67). Sap flow variation between seasons and across locations in all the species studied indicated two distinct groups. Group 1 transpired the least during the hottest season, November–December, and Group 2 the most. In Group 1, the highest average SFD was 1.17 l cm?2 day?1 during July–August; in Group 2, it was 1.07 l cm?2 day?1 during November–December. Changes in the hydrology of the delta would negatively affect the riparian woodland. 相似文献
11.
Oya Bozdağ‐Dündar Selen Gürkan Hassan Y. Aboul‐Enein Irena Kruk Aleksandra Kładna 《Luminescence》2009,24(3):194-201
The antioxidant behavior of a series of new synthesized substituted thiazolyl‐thiazolidine‐2,4‐dione compounds (TZDs) was examined using chemiluminescence and electron paramagnetic resonance spin trapping techniques. 5,5‐Dimethyl‐1‐pyrroline‐N‐oxide (DMPO) was used as the spin trap. The reactivity of TZDs with superoxide anion radical (O) and hydroxyl radical (HO?) was evaluated using potassium superoxide/18‐crown‐6 ether dissolved in dimethylsulfoxide, and the Fenton‐like reaction (Fe2+ + H2O2), respectively. The results showed that TZDs efficiently inhibited light emission from the O generating system at a concentration of 0.05–1 mmol L?1 (5–94% reductions were found at 1 mmol L?1 concentration). The TZD compounds showed inhibition of HO?‐dependent DMPO–OH spin adduct formation from DMPO (the amplitude decrease ranged from 8 to 82% at 1 mmol L?1 concentration). The findings showed that examined TZDs had effective activities as radical scavengers. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
12.
Detection of metronidazole in honey and metronidazole tablets using carbon dots‐based sensor via the inner filter effect
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In this work, carbon dots (CDs) with a high quantum yield (22.3%) were easily prepared by hydrothermal pyrolysis of acid fuchsin 6B and hydrogen peroxide at 180°C for 10 h. The resultant CDs possess a narrow size distribution in the range of 2.6 to 3.2 nm and emit blue fluorescence. Interestingly, the absorption band of metronidazole (MTZ) centered at 318 nm can complementary overlap with the excitation band of the as‐prepared CDs centered at 320 nm, resulting in an inner filter effect (IFE) in high efficiency. In fact, the fluorescence quenching of the CDs depends on the concentration of MTZ. Therefore, a simple method for the detection of MTZ can be established using the CDs‐based sensor via the IFE. The linear range of the proposed method was 0–10 μg mL?1 with the limit of detection as low as 0.257 μg mL?1. This CDs‐based sensor had been applied for the detection of MTZ in honey and MTZ tablets with the recoveries in the range of 98.0% to 105.1% and 95.7% to 106.5%, respectively. Therefore, the as‐prepared CDs have a potential to be developed as a MTZ sensor with high selectivity, sensitivity and accuracy. 相似文献
13.
Micelle‐enhanced spectrofluorimetric method for quantification of entacapone in tablets and human plasma
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In this paper, a simple and highly sensitive spectrofluorimetric method was developed and validated for the determination of entacapone (ETC). The proposed method is based on forming a highly fluorescent product through the reduction of ETC with Zn/HCl. The produced fluorophore exhibits strong fluorescence at λem 345 nm after excitation at λex 240 nm. The use of fluorescence enhancers such as Tween‐80 and carboxy methyl cellulose (CMC) greatly enhanced the fluorescence of the produced fluorophore by 150% and 200%, respectively. Calibration curves showed good linear regression (r2 > 0.9998) within test ranges of 0.05–2.0 and 0.02–1.80 μg mL?1 with lower detection limits of 1.27 × 10?2 and 4.8 × 10?3 μg mL?1 and lower quantification limits of 4.21 × 10?2 and 1.61 × 10?2 μg mL?1 upon using Tween‐80 and or CMC, respectively. The method was successfully applied to the analysis of ETC in its pharmaceutical formulations (either alone or in presence of other co‐formulated drugs). The results were in good agreement with those obtained using the official method. The methods were further extended to determine the drug in human plasma samples, and to study the pharmacokinetics of ETC. The paper is the first report on the spectrofluorimetric determination of entacapone. 相似文献
14.
Jaime Barros‐Rios Aloia Romaní Gil Garrote Bernardo Ordas 《Global Change Biology Bioenergy》2015,7(1):153-160
Sweet corn is a widely distributed crop that generates agricultural waste without significant commercial value. In this study, we show that sweet corn varieties produce large amounts of residual biomass (10 t ha?1) with high content of soluble sugars (25% of dry matter) in a short growing season (3 months). The potential ethanol production from structural and soluble sugars extracted from sweet corn stover reached up to 4400 l ha?1 in the most productive hybrids, 33% of which (1500 l ha?1) were obtained by direct fermentation of free sugars. We found wide genetic variation for biomass yield and soluble sugars content suggesting that those traits can be included as complementary traits in sweet corn breeding programs. Dual‐purpose sweet corn hybrids can have an added value for the farmers contributing to energy generation without affecting food supply or the environment. 相似文献
15.
A simply synthesized biphenyl substituted piperidin‐4‐one for the fluorescence chemosensing of Cd2+
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Sumathi Poomalai Anju Kannan Padinjareveetil Sivaraj Ramasamy Tamil Selvan Govindaraj Mosae Selvakumar Paulraj Israel Vijayaraj Muthu Vijayan Enoch 《Luminescence》2017,32(8):1405-1410
Ion‐induced change in fluorescence is a straight‐forward method for detection of toxic metal ions showing immediate response. Cadmium ions are toxic to the environment. We report in this paper a piperidine‐4‐one‐based fluorescent chemosensor of Cd2+ ions, designed and synthesized by a simple method. The compound is characterized using infra‐red (IR) and 1H–NMR spectral techniques. The chemosensor showed Cd2+ ion selectivity and sensitivity in aqueous solution. The stoichiometry and the binding constants were determined using fluorescence spectroscopy. Piperidine‐4‐one shows a 1:1 stoichiometric binding to Cd2+. The limit of detection of Cd2+ was reported. 相似文献
16.
Marcelo Der Torossian Torres Cibele Nicolaski Pedron Julia Aparecida da Silva Lima Pedro Ismael da Silva Junior Fernanda Dias da Silva Vani Xavier Oliveira Junior 《Journal of peptide science》2017,23(11):818-823
Linear cationic α‐helical antimicrobial peptides are promising chemotherapeutics. Most of them act by different mechanisms, making it difficult to microorganisms acquiring resistance. Decoralin is an example of antimicrobial peptide; it was described by Konno et al. and presented activity against microorganisms, but with pronounced hemolytic activity. We synthesized leucine‐substituted decoralin analogs designed based on important physicochemical properties, which depend on the maintenance of the amphiphilic α‐helical tendency of the native molecule. Peptides were synthesized, purified, and characterized, and the conformational studies were performed. The results indicated that the analogs presented both higher therapeutic indexes, but with antagonistic behavior. While [Leu]10‐Dec‐NH2 analog showed similar activity against different microorganisms (c.a. 0.4–0.8 μmol L?1), helical structuration, and some hemolytic activity, [Leu]8‐Dec‐NH2 analog did not tend to helical structure and presented antimicrobial activities two orders higher than the other two peptides analyzed. On the other hand, this analog showed to be the less hemolytic (MHC value = 50.0 μmol L?1). This approach provided insight for understanding the effects of the leucine substitution in the amphiphilic balance. They led to changes on the conformational tendency, which showed to be important for the mechanism of action and affecting antimicrobial and hemolytic activities. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
17.
Leaf‐Mosaic‐Inspired Vine‐Like Graphitic Carbon Nitride Showing High Light Absorption and Efficient Photocatalytic Hydrogen Evolution
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Yi Zhang Lanlan Wu Xinyu Zhao Yingnan Zhao Huaqiao Tan Xia Zhao Yuanyuan Ma Zhao Zhao Shuyan Song Yonghui Wang Yangguang Li 《Liver Transplantation》2018,8(25)
Green plants use solar energy efficiently in nature. Simulating the exquisite structure of a natural photosynthesis system may open a new approach for the construction of desirable photocatalysts with high light harvesting efficiency and performance. Herein, inspired by the excellent light utilization of “leaf mosaic” in plants, a novel vine‐like g‐C3N4 (V‐CN) is synthesized for the first time by copolymerizing urea with dicyandiamide‐formaldehyde (DF) resin. The as‐prepared V‐CN exhibits ultrahigh photocatalytic hydrogen production of 13.6 mmol g?1 h?1 under visible light and an apparent quantum yield of 12.7% at 420 nm, which is ≈38 times higher than that of traditional g‐C3N4, representing one of the highest‐activity g‐C3N4‐based photocatalysts. This super photocatalytic performance is derived from the unique leaf mosaic structure of V‐CN, which effectively improves its light utilization and affords a larger specific surface area. In addition, the introduction of DF resin further optimizes the energy band of V‐CN, extends its light absorption, and improves its crystallinity and interfacial charge transport, resulting in high performance. It is an easy and green strategy for the preparation of broad‐spectrum, high‐performance g‐C3N4, which presents significant advancement for the design of other nanophotocatalysts by simulating the fine structure of natural photosynthesis. 相似文献
18.
Irena Kruk Oya Bozdağ‐Dündar Rahmiye Ertan Hassan Y. Aboul‐Enein Teresa Michalska 《Luminescence》2009,24(2):96-101
The oxygen free radical scavenging activities of 15 chromonyl‐thiazolidine‐2,4‐dione compounds (CTDs) were examined in chemical systems producing superoxide anion radicals, O (potasium superoxide–18‐crown‐6 ether–DMSO), and hydroxyl radicals, HO? (a Fenton reaction: Fe(II)–H2O2–sodium trifluoroacetate, pH 6.15). Chemiluminescence and electron spin resonance (ESR) spectroscopy using 5,5‐dimethyl‐1‐pyrroline‐1‐oxide (DMPO) as spin trap were applied to evaluate antioxidant behaviour of CTDs towards the oxygen radicals. The results indicated that 11 of the 15 tested compounds showed a significant inhibitory effect on the chemiluminescence generated from the O‐generating system, ranging from 41 to 86%, and 13 CTDs quenched the ESR signal of the DMPO–OH spin adduct by 33–86%, at a concentration of 1 mmol L?1. Our findings demonstrate that CTDs could be good free radical scavengers. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
19.
A new system for the determination of nucleic acid by rare earth metallic porphyrin of [tetra‐(3‐methoxy‐4‐hydroxyphenyl)]–Tb3+ [T(3‐MO‐4HP)–Tb3+] porphyrin as fluorescence spectral probe has been developed in this paper. Nucleic acid can enhance the fluorescence intensity of the T(3‐MO‐4HP)–Tb3+ porphyrin in the presence of bis(2‐ethylhexyl)sulfosuccinate sodium salt(AOT) micelle. In pH 8.00 Tris–HCl buffer solution, under optimum conditions, the enhanced fluorescence intensity is in proportion to the concentration of nucleic acids in the range of 0.05–3.00 µg mL?1 for calf thymus DNA (ct DNA) and 0.03–4.80 µg mL?1 for fish sperm DNA(fs DNA). Their detection limits are 0.03 and 0.01 µg mL?1, respectively. In addition, the binding interaction mechanism between T(3‐MO‐4HP)–Tb3+ porphyrin and ct DNA is also investigated by resonance scattering and fluorescence spectra. The maximum binding number is calculated by molar ratio method. The new system can be used for the determination of nucleic acid in pig liver, yielding satisfactory results. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
20.
Synthesis and characterization of high quantum yield and oscillator strength 6‐chloro‐2‐(4‐cynophenyl)‐4‐phenyl quinoline (cl‐CN‐DPQ) organic phosphor for solid‐state lighting
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A novel blue luminescent 6‐chloro‐2‐(4‐cynophenyl) substituted diphenyl quinoline (Cl‐CN DPQ) organic phosphor has been synthesized by the acid‐catalyzed Friedlander reaction and then characterized to confirm structural, optical and thermal properties. Structural properties of Cl‐CN‐DPQ were analyzed by Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR) spectroscopy, X‐ray diffraction technique (XRD) and scanning electron microscopy (SEM) and energy dispersive analysis of X‐ray (EDAX) spectroscopy. FTIR spectra confirmed the presence of different functional groups and bond stretching. 1H–NMR and 13C–NMR confirmed the formation of an organic Cl‐CN‐DPQ compound. X‐ray diffraction study provided its crystalline nature. The surface morphology of Cl‐CN‐DPQ was analyzed by SEM, while EDAX spectroscopy revealed the elemental analysis. Differential thermal analysis (TGA/DTA) disclosed its thermal stability up to 250°C. The optical properties of Cl‐CN‐DPQ were investigated by UV–vis absorption and photoluminescence (PL) measurements. Cl‐CN‐DPQ exhibits intense blue emission at 434 nm in a solid‐state crystalline powder with CIE co‐ordinates (0.157, 0.027), when excited at 373 nm. Cl‐CN‐DPQ shows remarkable Stokes shift in the range 14800–5100 cm?1, which is the characteristic feature of intense light emission. A narrow full width at half‐maximum (FWHM) value of PL spectra in the range 42–48 nm was observed. Oscillator strength, energy band gap, quantum yield, and fluorescence energy yield were also examined using UV–vis absorption and photoluminescence spectra. These results prove its applications towards developing organic luminescence devices and displays, organic phosphor‐based solar cells and displays, organic lasers, chemical sensors and many more. 相似文献