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LED光色电综合性能分析测试原理与仪器 被引量:12
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作者 潘建根 《液晶与显示》 CAS CSCD 2003年第2期138-140,共3页
光色电综合性能参数是LED的主要技术指标,LED光色电综合性能的准确快速测量,对LED研发、制造和品质具有重要意义。本文介绍了LED光色电综合性能分析测试原理和仪器的主要技术指标,仪器满足CIE推荐标准条件。
关键词 LED 光色电综合性能分析 测试原理 测试仪器 CIE标准条件 技术指标 发光二极管
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论建筑风景色彩写生
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作者 潘绍元 《艺术百家》 北大核心 2006年第7期86-88,共3页
建筑色彩风景写生是建筑美术技术性较强的一门课程,实际能力的提高总是产生于种种成功和失败的经验,解决感觉色彩的能力这一素质的根本性问题是这一门课的关键。
关键词 色彩写生 光色分析 色彩感觉
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Anti-ultraviolet aging tests of asphalts adapting to environment in Tibetan Plateau of China 被引量:15
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作者 廖公云 黄晓明 巴桑顿珠 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期503-507,共5页
Ultraviolet (UV) aging is one of the main factors which cause premature damage of asphalt pavements in the Tibetan Plateau, China. According to the measured levels of UV radiation, aging tests of styrene-butadiene r... Ultraviolet (UV) aging is one of the main factors which cause premature damage of asphalt pavements in the Tibetan Plateau, China. According to the measured levels of UV radiation, aging tests of styrene-butadiene rubber (SBR) asphalts with different contents of three anti-UV-aging agents including nano-TiO2, CeO2 and carbon black are performed. Common indices, which include retained penetration after thin film oven tests (TFOT) and softening point, and strategic highway research program (SHRP) indices of aged asphalts are evaluated. Infrared absorption spectral analysis is performed on asphalt specimens with 0. 8% carbon black which have been aged for different aging times (500, 1000 and 1 500 h). By grey incidence analysis, the optimal contents of anti-UV-aging agents are determined. The results show that TiO2 and CeO2 are not only good UV absorbing or shielding agents, but also strong oxidants. Carbon black is a good anti-UV-aging agent, and its optimal content is about 0. 8% of asphalt weight. UV aging of asphalt mainly occurs in the early stages of aging. The longer the aging time, the more severe the aging of asphalt. 展开更多
关键词 ultraviolet (UV) aging agent carbon black infrared absorption spectral analysis grey incidence analysis
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Low-dimensional multi-spectral space for color reproduction based on nonnegative constrained principal component analysis 被引量:1
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作者 王莹 曾平 +1 位作者 罗雪梅 谢琨 《Journal of Southeast University(English Edition)》 EI CAS 2009年第4期486-490,共5页
In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonne... In order to overcome the shortcomings that the reconstructed spectral reflectance may be negative when using the classic principal component analysis (PCA)to reduce the dimensions of the multi-spectral data, a nonnegative constrained principal component analysis method is proposed to construct a low-dimensional multi-spectral space and accomplish the conversion between the new constructed space and the multispectral space. First, the reason behind the negative data is analyzed and a nonnegative constraint is imposed on the classic PCA. Then a set of nonnegative linear independence weight vectors of principal components is obtained, by which a lowdimensional space is constructed. Finally, a nonlinear optimization technique is used to determine the projection vectors of the high-dimensional multi-spectral data in the constructed space. Experimental results show that the proposed method can keep the reconstructed spectral data in [ 0, 1 ]. The precision of the space created by the proposed method is equivalent to or even higher than that by the PCA. 展开更多
关键词 spectral color science nonnegative constrained principal component analysis low-dimensional spectral space nonlinear optimization multi-spectral images spectral reflectance
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Extraction of essential oil from shaddock peel and analysis of its components by gas chromatography-mass spectrometry 被引量:2
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作者 周尽花 周春山 +1 位作者 蒋新宇 谢练武 《Journal of Central South University of Technology》 EI 2006年第1期44-48,共5页
Essential oil, with more than thirty kinds of compounds separated and identified by gas chromatography-mass spectrometry, was extracted from Shatian shaddock peel and Sweet shaddock peel by squeeze-steam distillation ... Essential oil, with more than thirty kinds of compounds separated and identified by gas chromatography-mass spectrometry, was extracted from Shatian shaddock peel and Sweet shaddock peel by squeeze-steam distillation and direct steam distillation method. Among their composition, the main components are terpene compounds, which account for 93.926% (mass fraction, the same below) and 85.843% of essential oils extracted from Shatian shaddock peel and Sweet shaddock peel, respectively. Although nootkatone is the major contributor of shaddock characteristic scent, and its contents are 1.069% and 1.749% of essential oils from Sweet shaddock peel and Shatian shaddock peel, respectively. The results show that squeeze-steam distillation gives higher yield and good quality of essential oil and the compositions of essential oils from two kinds of shaddock peels are different, but the main contributors of the shaddock scent are the same. 展开更多
关键词 essential oil Shatian shaddock Sweet shaddock gas chromatography - mass spectrometry nootkatone EXTRACTION
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Determination of Baicalin in Traditional Chinese Preparation by High Performance Liquid Chromatography with Chemiluminescence Detection 被引量:5
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作者 ErBaoLIU HongQingWEI XiuLiZHAO XiaoXiaLI FengXianJIANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第9期1067-1070,共4页
A new method for the determination of baicalin with HPLC-CL was developed. The method was based on the chemiluminescence reaction between KMnO4 and baicalin sensitized from HCHO. The linear range was 3.7?0-6~9.8?0-5... A new method for the determination of baicalin with HPLC-CL was developed. The method was based on the chemiluminescence reaction between KMnO4 and baicalin sensitized from HCHO. The linear range was 3.7?0-6~9.8?0-5 mol/L with detection limit of 1.7?0-6 mol/L and the relative standard deviation was 2.5 % (Cs=6.6?0-5 mol/L, n=5). The method has been applied to the determination of baicalin in oral administration, injection, Scutellariae radix and granules with good results. 展开更多
关键词 RP-HPLC chemiluminescence analysis baicalin.
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Involvement of the Nerve Fibers in the Human Skin Neurofibromatosis
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作者 Tammaro Antonella Cavallotti Claudia +6 位作者 Parisella Francesca Romana Giulianelli Veronica Gabriella De Marco Elena Pacella Femanda Pacella Persechino Severino Cavallotti Carlo 《Journal of Life Sciences》 2015年第1期32-39,共8页
Neurofibromatosis type 2 is a well known disease of the human skin. Its microscopic and ultramicroscopic features are also well defined. Aim: The aim of this work was to study the involvement of catecholaminergic ner... Neurofibromatosis type 2 is a well known disease of the human skin. Its microscopic and ultramicroscopic features are also well defined. Aim: The aim of this work was to study the involvement of catecholaminergic nerve fibers in the human skin neurofibromatosis. Bioptic fragments of the human skin have been harvested from healthy and diseased subjects. On these specimens the following analysis were performed: 1) light microscopic observation after colouring with hematoxyline-Eosine. 2) lmmunochemical staining for Protein Gene Product 9.5.3) Fluorescent staining for catecholaminergic nerve fibers. 4) Quantitative analysis of images by means of the Quantimet analyzer Leica. 5) Statistical analysis of the quantitative morphological data comparing the healthy with diseased subjects. Comparing the light microscopy images in normal and pathological subjects the authors can affirm that the skin neurofibromatosis induces a strong decrease of the nerve fibers cutted in small pieces and destroyed. Also the catecholaminergic nerve fibers are strongly reduced and destroyed. Quantitative analysis of images and statistical analysis of the morphological data confirm that neurofibromatosis induces strong changes of the skin nerve fibers. The authors' results confirm that the neurofibromatosis type 2 induces an almost total destruction of the skin nerve fibers. 展开更多
关键词 NEUROFIBROMATOSIS humans skin nerve fibers cathecolaminergic fibers.
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Synthesis and emission analysis of novel rare earth complex Eu(TTA)_3(2NH_2-Phen) 被引量:1
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作者 吕玉光 李刚 +3 位作者 石春卉 于连生 栾芳 张福俊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第12期2336-2339,共4页
The rare earth ternary complex of Eu 3+ with thenoyltrifluoroacetone,and 4,7-2NH2 phenanthroline was synthesized and well characterized by UV,fluorescent,IR spectrometry and X-ray diffractometry(XRD)as well as element... The rare earth ternary complex of Eu 3+ with thenoyltrifluoroacetone,and 4,7-2NH2 phenanthroline was synthesized and well characterized by UV,fluorescent,IR spectrometry and X-ray diffractometry(XRD)as well as elemental analysis.The results show that the complex of Eu(III)emits strong red luminescence when excited by UV light,and Eu(TTA)3(2NH2-Phen)has the higher sensitized luminescent efficiency and longer lifetime than Eu(TTA)3(Phen).In device of ITO/PVK/Eu(TTA)3(2NH2-Phen)/Al,the spectra of Eu(TTA)3(2NH2-Phen)with different ratios for spin-cast film were monitored.The main emitting peak at 614 nm can be attributed to the transition of 5 D0→ 7 F2 of Eu 3+ and this process results in the enhancement of red emission from electroluminescence device.The effect and mechanism of the ligands on the luminescence properties of europium complex were discussed.The results show that the luminescence intensity of the title complexes greatly increases in comparison with that of their corresponding complexes,revealing that the second ligands form very good synergistic effect with the first ligands.The title complexes possess excellent thermal stability properties,and are hopefully developed into fine PL and EL red materials. 展开更多
关键词 SYNTHESIS ternary complex LUMINESCENCE ELECTROLUMINESCENCE
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Cloning and Characterization of Phytochrome A Gene Fa PHYA from Tall Fescue
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作者 王小利 吴佳海 +3 位作者 舒健虹 蔡一鸣 刘晓霞 李小冬 《Agricultural Science & Technology》 CAS 2015年第9期1851-1856,共6页
The sequence fragment of PHYA, obtained from transcriptome sequencing,was used as the template, and the full-length c DNA sequence of PHYA gene in tall fescue was amplified using 3'RACE and 5'RACE techniques. The c ... The sequence fragment of PHYA, obtained from transcriptome sequencing,was used as the template, and the full-length c DNA sequence of PHYA gene in tall fescue was amplified using 3'RACE and 5'RACE techniques. The c DNA sequence of PHYA gene has a complete open reading frame(ORF, 293-6 682 bp), and it encodes a protein composed of 1 129 amino acids. The N-terminal of Fa PHYA is composed of GAF and Phytochrome domains, and its C-terminal contains two repeated PAS domains, one histidine kinase A domain and one histidine kinase-like ATPase domain. The homology analysis showed that the amino acid sequences of Fa PHYA of tall fescue and PHYAs of gramineous plants have higher homologies(85%), indicating close genetic relationships. However, the homologies between FaPHYA of tall fescue and PHYAs of monocotyledons are lower, indicating far genetic relationships. 展开更多
关键词 Tall fescue Phytochrome A gene CLONING BIOINFORMATICS
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Study of oxidization of coal–pitch by O_3 被引量:2
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作者 Wang Yaoling Chen Sishun +1 位作者 Ding Mingjie Xu Zhan 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期677-681,共5页
For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studi... For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studied. The coal-pitch sample and the oxidized pitch residue were characterized by elementary analysis and Fourier transform infrared spectroscopy (FTIR), while the small molecular products were analyzed by a gas chromatography-mass spectrometer (GC-MS). The results show that the highest oxygen content of oxidized coal pitch had been acquired at a reaction temperature of 50℃C, an 03 flow rate of 6300 mg/h and a reaction time of 4 h. Quite a lot of hydroxyls and carbonyls were introduced into the structure of the oxidized coal-pitch, while the small molecules produced mainly involve nonpolar aro- matic compounds, aromatic anhydride and quinone compounds. It is speculated that the mechanism is direct electrophilic oxidation in which the molecules of 03 directly attack the aromatic ring at its carbon atoms with high electron density, and then generate hydroxyl or carbonyl until the aromatic ring cracks. This study shows that 03 can make the fused aromatic ring of coal-pitch become oxidized and depoly- merized, and hence the ozonization of coal-pitch can be a potential method for obtaining oxygen- containing aromatic compounds. 展开更多
关键词 Study Coal-pitch Ozone oxidation Depolymerization
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Optimization of Yield and Chemical Properties of Agar Extracted from Melanothamnus Somalensis from Oman Sea
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作者 Zainab Mohammed Al-Nahdi Ahmed Al-Alawi +1 位作者 Insaaf Al-Marhobi Ali Al-Zefiti 《Journal of Environmental Science and Engineering(B)》 2015年第6期302-314,共13页
The red seaweed Melanothamnus somalensis was investigated as potential economic source of agar. The effect of different conditions of alkali pre-treatment on chemical properties of agar was evaluated. Agar was extract... The red seaweed Melanothamnus somalensis was investigated as potential economic source of agar. The effect of different conditions of alkali pre-treatment on chemical properties of agar was evaluated. Agar was extracted by various concentrations of NaOH (4%, 6% and 8%) and heated at different temperatures (70 ℃, 75 ℃ and 80 ℃) for different durations (2 h, 2.75 h and 3.5 h). The yields-molecular weight (Mw) and sulfate contents of extracted agar were analysed and characterized by FTIR spectroscopy. The yield was significantly increased at these treatments from 23.29% to 30.86%. Mw studied by HPLC ranged from (.12.45 ± 0.21) × 10^5 to (8.60 ± 2.40) × 10^5 Da. FTIR bands show sulfate groups in C4 and C6 ofgalactose and no sulfate group were found on both C2 of galactose and C2 of 3,6-anhydrogalactose. All treatments showed a high sulfate content that ranged from 5.4% to 10.1%. These properties were found to be significantly affected by the alkali pre-treatment concentration (p 〈 0.05). In conclusion, agar extracted in this study was considered acceptable for industrial application and the optimal conditions for extraction were found to be at 6% NaOH at 70 ℃ for 2 hours. 展开更多
关键词 SEAWEED Melanothamnus somalensis agarophytes agar extraction alkali pre-treatment FTIR.
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Bone Marrow Urokinase Plasminogen Activator Receptor Levels are Associated with the Progress of Multiple Myeloma
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作者 Li-hong Shou Dan Cao +3 位作者 Xiao-hui Dong Qiu Fang Bao-lian Xu Ju-ping Fei 《Chinese Medical Sciences Journal》 CAS CSCD 2016年第3期155-160,共6页
Objective To determine the mRNA and protein levels of urokinase plasminogen activator receptors(u PAR) in bone marrow fluid and bone marrow tissue from multiple myeloma(MM) patients and assess association of u PAR lev... Objective To determine the mRNA and protein levels of urokinase plasminogen activator receptors(u PAR) in bone marrow fluid and bone marrow tissue from multiple myeloma(MM) patients and assess association of u PAR level with prognosis of MM.Methods u PAR levels in bone marrow fluid of 22 MM patients at the stable and progressive stages and 18 iron deficiency anemia patients with normal bone marrow(control) were examined by ELISA.Furthermore,u PAR expression in bone marrow tissue was investigated by RT-PCR and Western blot,respectively.The distribution of u PAR in MM cells was examined using immunofluorescence staining.The pathological changes in different stages of MM patients were studied by HE staining.Results u PAR level in bone marrow fluid of MM patients(1.52±0.32 μg/ml) was found to be higher than that in the control group(0.98±0.15 μg/ml).Interestingly,u PAR protein(0.686±0.075 vs.0.372±0.043,P<0.05) and m RNA(2.51±0.46 vs.4.46±1.15,P<0.05) expression levels of MM patients at the progressive stage were significantly higher than those at the stable stage.The expression of u PAR in MM bone marrow was confirmed by immunofluorescence staining.Moreover,HE staining revealed a great increased number of nucleated cells and severe impairment of hematopoietic function in the bone marrow of patients with progressive-stage myeloma.Conclusion Our study reveals that u PAR expression is positively correlated with the development and progress of MM. 展开更多
关键词 multiple myeloma urokinase-type plasminogen activator receptor bone marrow UROKINASE
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Validation of Analytical Method of Irbesartan Plasma in Vitro by High Performance Liquid Chromatography-Fluorescence
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作者 Harmita Yahdiana Harahap I. Kadek Arya M. 《Journal of Life Sciences》 2012年第7期726-731,共6页
Irbesartan is an antihypertensive drug whose concentration in blood is very small so it requires a sensitive method of analysis, selective and valid for analysis. In this study, it is carried out optimization of analy... Irbesartan is an antihypertensive drug whose concentration in blood is very small so it requires a sensitive method of analysis, selective and valid for analysis. In this study, it is carried out optimization of analytical conditions and validation for the analysis of irbesartan in plasma. Chromatography was performed on a C 18 column (250 × 4.6 mm, 5 μm) under isocratic elution with acetonitrile-0.1% formic acid (46:54 v/v), pH 3.75. Detection was made at excitation 250 nm and emission 370 nm and analyses were run at a flow-rate of 1.0 mL/min at a temperature of 40 ℃. Losartan potassium was used as internal standard. Plasma extraction was done by deproteination with acetonitrile, mixed with vortex for 30 seconds, then centrifuged it at 10,000 rpm for 10 rain. In plasma validation, the recovery was 96.22%, and the lower limit of quantification (LLOQ) in plasma was 2 ng/mL. The method also fulfill the criteria for accuracy and precision intra and inter day by normal values (%Diff) not exceed ± 15%. On the stability study, irbesartan in plasma temperature -20 ℃has been stable for 28 days. 展开更多
关键词 HPLC FLUORESCENCE IRBESARTAN VALIDATION human plasma.
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Effect of Fusariosis on the Metabolism of Phenolics Compounds of Date Palm Leaflets, Resistant and Sensitive to the Disease
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作者 Saida Ouafi Nicole Bounaga 《Journal of Food Science and Engineering》 2012年第4期213-217,共5页
Because of socio-economic importance of date palm in North Africa, the scientific community has always followed the progression of parasitic disease that affects it. The study was performed on population of thirty pal... Because of socio-economic importance of date palm in North Africa, the scientific community has always followed the progression of parasitic disease that affects it. The study was performed on population of thirty palm trees belonging to three cultivars of the oases of south-west Algeria TOUAT Gourara. The analytical protocol consists of a hot hydrochloric acid hydrolysis of I g of leaf material dried and ground. Structural analysis of compounds present in extracts was conducted by chromatographic and spectrophotometric techniques. Through the analysis of all HPLC profiles of phenolic acids, we have established three chemotypes: resistant with the highest heights, sensitive, with the lowest height, finally low sensitivity or tolerant with intermediate heights. The increased synthesis of C-glycoflavones, within diseased palms, can be seen as the first sign of plant response to fungal attack, or even as a defense mechanism so these flavonoids correspond to "pre-inhibitines". It has not been found qualitative differences between different cultivars studied. The merits of our work show a negative correlation between flavonoid content and the level of lignification in the date palm, suggests that the process of lignification is more rapid in resistant cultivars. We can say that there is a constitutive resistance. 展开更多
关键词 Date palm tree fusariose CHEMOTYPE RESISTANT phenolic compounds.
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Novel Quantum Phases of Ultracold Bosonic Atoms in Honeycomb Optical Lattice
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作者 陆青青 侯净敏 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期861-863,共3页
We study the quantum phase transition of ultracold atoms in the honeycomb optical lattice. The Hamiltonian of ultracold bosonic atoms in the honeycomb optical lattice is derived. We take the mean-field approximation a... We study the quantum phase transition of ultracold atoms in the honeycomb optical lattice. The Hamiltonian of ultracold bosonic atoms in the honeycomb optical lattice is derived. We take the mean-field approximation and further solve the Hamiltonian with the numerical diagonalization method. We obtain the phase diagram and find that the Mort-insulator (MI), density wave (DW) and modulated superfluid (MS) phases appear. Furthermore, the phase diagram is analyzed according to the order parameter and the average number of particles. 展开更多
关键词 honeycomb optical lattice quantum phase transition ultracold atoms
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LED光、色、电参数综合性能分析测试原理与仪器
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《中国照明电器》 2002年第12期24-25,共2页
光色电综合性能是LED的主要技术指标 ,LED光色电综合性能的准确快速测量 ,对LED研发、制造具有重要意义。本文介绍了LED光色电综合性能分析测试原理和仪器的主要技术指标 。
关键词 光色电综合性能分析测试仪 光源 LED 测试原理 光色电综合性能参数
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Establishment of an HPLC method for the analysis of biapenem and its impurities 被引量:1
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作者 王楠 李春凤 +1 位作者 张斗胜 胡昌勤 《Journal of Chinese Pharmaceutical Sciences》 CAS 2011年第2X期171-180,共10页
An HPLC method for routine quality control of biapenem was established.A Dikma Diamonsil C_(18) column(250mm×4.6 mm,5μm) was used with diode array detection and single wavelength detection at 220 nm.The mobile p... An HPLC method for routine quality control of biapenem was established.A Dikma Diamonsil C_(18) column(250mm×4.6 mm,5μm) was used with diode array detection and single wavelength detection at 220 nm.The mobile phase was consisted of acetonitrile-0.1%triethylamine water(1:99,v/v).The liner range for biapenem quantification was 0.05-10.0 mg/mL(r^2= 0.999). The LOD and LOQ of impurity were 4.8 ng(S/N = 3) and 18.5 ng(S/N = 10),respectively.Intra-day RSD of main impurity and total impurity were 1.84%and 3.37%(n = 3);inter-day RSD of main impurity and total impurity were 4.84%and 7.58% (n = 9).The test solution was stable when stored at 4℃for 6 h.The impurity peaks of biapenem can be identified by chromatographic spectral correlation analysis using high-performance liquid chromatography-diode array detection data from the quality control method by calculating correlation coefficients without reference standards.Two hydrolysis degradation products with relative retention times(RRTs) of 0.528 and 0.743,two dimers with RRTs of 1.062 and 2.817 were identified in the quality control chromatogram.It provides a new way to identify impurity peaks by the routine HPLC-UV method. 展开更多
关键词 BIAPENEM HPLC-DAD Two-dimensional chromatographic spectral correlative map Identification IMPURITIES
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True-color real-time imaging and spectroscopy of carbon nanotubes on substrates using enhanced Rayleigh scattering 被引量:1
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作者 Wenyun Wu Jingying Yue +21 位作者 Xiaoyang Lin Dongqi Li Fangqiang Zhu Xue Yin Jun Zhu Jiangtao Wang Jin Zhang Yuan Chen Xinhe Wang Tianyi Li Yujun He Xingcan Dai Peng Liu Yang wei Jiaping Wang Wei Zhang Yidong Huang Li Fan Lina Zhang Qunqing Li Shoushan Fan Kaili Jiang 《Nano Research》 SCIE EI CAS CSCD 2015年第8期2721-2732,共12页
Single-walled carbon nanotubes (SWCNTs) illuminated by white light should appear colored due to resonance Rayleigh scattering. However, true-color imaging of SWCNTs on substrates has not been reported, because of th... Single-walled carbon nanotubes (SWCNTs) illuminated by white light should appear colored due to resonance Rayleigh scattering. However, true-color imaging of SWCNTs on substrates has not been reported, because of the extremely low scattering intensity of SWCNTs and the strong substrate scattering. Here we show that Rayleigh scattering can be greatly enhanced by the interface dipole enhancement effect. Consequently colorful SWCNTs on substrates can be directly imaged under an optical microscope by wide field supercontinuum laser illumination, which facilitates high throughput chirality assignment of individual SWCNTs. This approach, termed "Rayleigh imaging microscopy", is not restricted to SWCNTs, but widely applicable to a variety of nanomaterials, which enables the colorful nanoworld to be explored under optical microscopes. 展开更多
关键词 enhanced Rayleigh scattering Rayleigh imaging microscopy true-color imaging carbon nanotube interface dipole
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Biodegradation of Pentachloronitrobenzene by Labrys portucalensis pcnb-21 Isolated from Polluted Soil 被引量:2
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作者 LI Rong ZHENG Jin-Wei NI Bin CHEN Kai YANG Xiu-Juan LI Shun-Peng JIANG Jian-Dong 《Pedosphere》 SCIE CAS CSCD 2011年第1期31-36,共6页
A bacterial strain, pcnb-21, capable of degrading pentaehloronitrobenzene (PCNB) under aerobic and anoxic conditions, was isolated from a long-term PCNB-polluted soil by an enrichment culture technique and identifie... A bacterial strain, pcnb-21, capable of degrading pentaehloronitrobenzene (PCNB) under aerobic and anoxic conditions, was isolated from a long-term PCNB-polluted soil by an enrichment culture technique and identified as Labrys portucalensis based upon its morphological, physiological and biochemical properties, as well as 16S rRNA gene sequence analysis. Effects of different factors, such as temperature and pH, on PCNB biodegradation were studied. Strain pcnb-21 efficiently degraded PCNB at temperatures from 20 to 30 ℃ and initial pH values from 4 to 7, which might be the first time that a Labrys strain was found capable of eflClciently degrading PC1NB. The degradation of PCNB was affected by oxygen, and the degradation decreased with increasing aeration. Exogenous electron donors such as glucose, lactic acid and succinic acid promoted the biodegradation of PCNB, while electron acceptors such as sodium nitrite, sodium sulfate, sodium nitrate and sodium sulfate inhibited PCNB biodegradation. The degradation of PCNB in sterile and non-sterile soils by a green fluorescent protein (GFP)-labeled strain, pcnb-21-gfp, was also studied. Cells of pcnb-21-gfp efficiently degraded 100 mg kg-1 PCNB in sterile and non-sterile soils and could not be detected after 42 days. Strain pcnb-21 might be useful in bioremediating PCNB-polluted soils and environment. 展开更多
关键词 AERATION bacterial strain electron acceptors electron donors sterile soil
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Photochemical hydrogen production with molecular devices comprising a zinc porphyrin and a cobaloxime catalyst 被引量:1
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作者 ZHANG Pan WANG Mei +3 位作者 LI XueQiang CUI HongGuang DONG JingFeng SUN LiCheng 《Science China Chemistry》 SCIE EI CAS 2012年第7期1274-1282,共9页
Two new noble-metal-free molecular devices, [{Co(dmgH)2Cl}{Zn(PyTPP)}] (1, dmgH = dimethyloxime, PyTPP = 5-(4- pyridyl)-10,15,20-triphenylporphyrin) and [{Co(dmgH)2Cl}{Zn(apPyTPP)}] (2, apPyTPP = 5-[4-(i... Two new noble-metal-free molecular devices, [{Co(dmgH)2Cl}{Zn(PyTPP)}] (1, dmgH = dimethyloxime, PyTPP = 5-(4- pyridyl)-10,15,20-triphenylporphyrin) and [{Co(dmgH)2Cl}{Zn(apPyTPP)}] (2, apPyTPP = 5-[4-(isonicotinamidyl)phenyl]- 10,15,20-triphenylporphyrin), for light-driven hydrogen generation were prepared and spectroscopically characterized. The zinc porphyrin photosensitizer and the Co III-based catalyst unit are linked by axial coordination of a pyridyl group in the periphery of zinc-porphyrin to the cobalt centre of catalyst with different lengths of bridges. The apparent fluorescence quenching and lifetime decays of 1 and 2 were observed in comparison with their reference chromophores, Zn(PyTPP) (3) and Zn(apPyTPP) (4), suggesting a possibility for an intramolecular electron transfer from the singlet excited state of zinc porphyrin unit to the cobalt centre in the molecular devices. Photochemical H2-evolving studies show that complexes 1 and 2 are efficient molecular photocatalysts for visible light-driven H2 generation from water with triethylamine as a sacrificial electron donor in THF/H20, with turnover numbers up to 46 and 35 for 1 and 2, respectively. In contrast to these molecular devices, the multicomponent catalyst of zinc porphyrin and [Co(dmgH)2PyCl] did not show any fluorescence quenching and as a consequence, no H2 gas was detected by GC analysis in the presence of triethylamine with irradiation of visible light. The plausible mechanism for the photochemical H2 generation with these molecular devices is discussed. 展开更多
关键词 COBALOXIME hydrogen production molecular device PHOTOCATALYSIS zinc porphyrin
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