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重组人促卵泡激素氧化亚基分析方法研究
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作者 杨慧敏 张伟 +6 位作者 孙悦 吕萍 王绿音 李懿 张慧 李晶 梁成罡 《药物分析杂志》 CAS CSCD 北大核心 2022年第1期33-40,共8页
目的:研究建立重组人促卵泡激素(rhFSH)氧化亚基分析方法,制备稳定的氧化亚基分析用系统适用性溶液。方法:通过加入过氧化氢氧化破坏重组人促卵泡激素,后加入甲硫氨酸终止该氧化作用,制备系统适用性溶液。采用RP-HPLC法分离分析重组人... 目的:研究建立重组人促卵泡激素(rhFSH)氧化亚基分析方法,制备稳定的氧化亚基分析用系统适用性溶液。方法:通过加入过氧化氢氧化破坏重组人促卵泡激素,后加入甲硫氨酸终止该氧化作用,制备系统适用性溶液。采用RP-HPLC法分离分析重组人促卵泡激素氧化亚基。使用C_(4)色谱柱(250 mm×4.6 mm,5μm);流动相A为0.2 mol·L^(-1)磷酸二氢钾缓冲液(pH 2.5),流动相B为80%乙腈;流速1 mL·min^(-1);柱温30℃;检测波长210 nm;梯度洗脱(0~10 min,82%A→74%A;10~25 min,74%A→60%A;25~26 min,60%A→20%A;26~56 min,20%A;56~56.1 min,20%A→82%A;56.1~75 min,82%A)。结果:加入甲硫氨酸可有效终止氧化作用,制备得到稳定的系统适用性溶液。优化建立的氧化亚基分析方法专属性良好,重复性(RSD=0.22%)、色谱柱耐用性(RSD=3.21%)、36 h内溶液稳定性(RSD=0.65%)结果良好。9批样品中氧化亚基含量范围为0.687%~1.001%。结论:优化建立的氧化亚基分析方法可对重组人促卵泡激素中的氧化亚基进行准确定量,能够用作重组人促卵泡激素的质量研究和放行检验;研究制备的系统适用性溶液可准确地对氧化亚基进行峰定位。 展开更多
关键词 糖蛋白 重组人促卵泡激素 氧化亚基 反相高效液相色谱 系统适用性 定量 质量控制
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非晶态氧化亚锡基硼磷铝酸盐(TABP)催化合成己酸异戊酯 被引量:2
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作者 杨水金 罗义 +2 位作者 梁永光 伍强 袁正勇 《香料香精化妆品》 CAS 2002年第6期11-13,26,共4页
介绍了非晶态氧化亚锡基硼磷铝酸盐 (TABP)催化剂的制备方法。首次以自制的非晶态氧化亚锡基硼磷铝酸盐作为催化剂 ,通过己酸和异戊醇反应合成了己酸异戊酯 ,并探讨了诸因素对收率的影响。实验表明 :非晶态氧化亚锡基硼磷铝酸盐 (TABP)... 介绍了非晶态氧化亚锡基硼磷铝酸盐 (TABP)催化剂的制备方法。首次以自制的非晶态氧化亚锡基硼磷铝酸盐作为催化剂 ,通过己酸和异戊醇反应合成了己酸异戊酯 ,并探讨了诸因素对收率的影响。实验表明 :非晶态氧化亚锡基硼磷铝酸盐 (TABP)催化剂具有良好的催化活性 ,醇酸物质的量比为 1.80∶1,催化剂用量为反应物料总量的 2 .2 5 %,反应时间 10 0min ,反应温度 142~ 15 4℃ ,收率可达 94.4%。 展开更多
关键词 非晶态氧化亚 硼磷铝酸盐 TABP 催化 合成 己酸异戊酯 酯化反应 合成香料
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非晶态氧化亚锡基硼磷铝酸盐催化合成乙酸正戊酯 被引量:3
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作者 罗义 梁永光 +1 位作者 杨水金 袁正勇 《精细石油化工进展》 CAS 2001年第10期15-17,共3页
介绍了非晶态氧化亚锡基硼磷铝酸盐(TABP)催化剂的制备方法。首次以自制的TABP作催化剂,通过乙酸和正戊醇反应合成了乙酸正戊酯,并探讨了诸因素对收率的影响。实验结果表明:TABP具有良好的催化活性,在醇酸物质的量比为1.30:1、催化剂用... 介绍了非晶态氧化亚锡基硼磷铝酸盐(TABP)催化剂的制备方法。首次以自制的TABP作催化剂,通过乙酸和正戊醇反应合成了乙酸正戊酯,并探讨了诸因素对收率的影响。实验结果表明:TABP具有良好的催化活性,在醇酸物质的量比为1.30:1、催化剂用量为反应物料总量的 1.5%、反应时间2.5 h、反应温度 124~134℃时,乙酸正戊酯的收率可达97.9%。 展开更多
关键词 非晶态 氧化亚 硼磷铝酸盐 TABP 乙酸正戊酯 催化剂 酯化反应
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氧化亚氮/乙烯推进剂预混燃烧特性试验研究 被引量:5
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作者 张锋 杨伟东 +1 位作者 胡洪波 杨岸龙 《火箭推进》 CAS 2019年第3期41-47,共7页
氧化亚氮基单元复合推进剂是一种新型、高能、无毒的单组元推进剂,具有广阔的应用前景。开展了氧化亚氮/乙烯推进剂在室压0.7MPa和1.0MPa条件下、混合比6.2~10.6范围内的预混燃烧特性试验,获得了混合比、燃烧室特征长度等对特征速度和... 氧化亚氮基单元复合推进剂是一种新型、高能、无毒的单组元推进剂,具有广阔的应用前景。开展了氧化亚氮/乙烯推进剂在室压0.7MPa和1.0MPa条件下、混合比6.2~10.6范围内的预混燃烧特性试验,获得了混合比、燃烧室特征长度等对特征速度和燃烧效率的影响规律。试验结果表明:当量孔径为65μm、厚度为5mm的不锈钢多孔材料具有良好的防回火效果,所有试验工况均未发生燃烧室回火现象;N2O/C2H4推进剂的理论特征速度和试验特征速度均随着混合比的增大而减小,最高燃烧效率达到了95.0%;随着燃烧室特征长度的不断增大,燃烧效率先增大后减小,对所试验的特定喷注器结构的铜热沉模型燃烧室来说,最佳的燃烧室特征长度在1.675m左右。 展开更多
关键词 氧化亚单元复合推进剂 乙烯 多孔材料 预混燃烧 特征速度 燃烧效率
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Preparation and improved photocatalytic activity of ordered mesoporous TiO_2 by evaporation induced self-assembly technique using liquid crystal as template 被引量:2
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作者 刘晨 李佑稷 +2 位作者 徐鹏 李泽时 曾孟雄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1072-1078,共7页
Ordered mesoporous TiO2 (OMPT) was prepared by an evaporation induced self-assembly technique using liquid crystal as template. The key factors affecting the methylene blue (MB) oxidation efficiency were investiga... Ordered mesoporous TiO2 (OMPT) was prepared by an evaporation induced self-assembly technique using liquid crystal as template. The key factors affecting the methylene blue (MB) oxidation efficiency were investigated, including the initial concentration of MB, pH value and catalyst concentration. The results show that the obtained OMPT has high thermal stability and shows a 2D hexagonal mesostructure with the small particle size and high surface area, which lead to higher degradation efficiency than commercial P25 or nanoparticle TiO2 (NPT) fabricated by sol-gel process. The optimal conditions are 5 mg/L MB, pH 6 and 1.5 g/L OMPT for the fastest rate of MB degradation. Total organic carbon (TOC) analysis indicates complete mineralization of MB in 240 min by OMPT, with rate constant higher than NPT or P25. 展开更多
关键词 TITANIA ordered mesopore liquid crystal template methylene blue degradation
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Cloning and Sequence Analysis of rbcS Gene of Wild Barley (Hordeum brevisubulatum) under Salt Stress 被引量:2
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作者 岳海燕 尹剑锐 +6 位作者 闫守庆 冯宇隆 张莲姬 郭建强 李怀亮 丁雪梅 沈景林 《Agricultural Science & Technology》 CAS 2010年第8期42-44,共3页
[Objective] The aim was to study the cloning and sequence analysis of rbcS gene of wild barley under salt stress. [Method] The tender leaf blade of wild barley under salt stress was taken as the experimental material.... [Objective] The aim was to study the cloning and sequence analysis of rbcS gene of wild barley under salt stress. [Method] The tender leaf blade of wild barley under salt stress was taken as the experimental material. The primers were designed according to the homology of rbcS gene sequences of wheat and barely in Genbank; then PCR amplification,recovery,ligation,transformation and sequencing of rbcS gene were carried out. [Result] Two rbcS genes including rbcS1 and rbcS2 with the length of 1 252 and 908 bp respectively were cloned from the barely genome. rbcS1 and rbcS2 were both composed by two exons and one intron. The exons length of the two genes was the same of 525 bp,encoding 174 amino acids,and the homology between them was 96%; however,the intron length of rbcS1 and rbcS2 was 448 and 107 bp respectively. 展开更多
关键词 Wild barley Salt stress Ribulose-1 5-Bisphosphate Carboxylase/Oxygenase Small Subunit Sequence analysis
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Flower-like Bi_2WO_6/ZnO composite with excellent photocatalytic capability under visible light irradiation 被引量:9
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作者 Juan Cheng Yi Shen +4 位作者 Kuan Chen Xi Wang Yongfu Guo Xiaoji Zhou Renbi Bai 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第4期810-820,共11页
The photocatalytic ability of ZnO is improved through the addition of flower‐like Bi2WO6 to prepare a Bi2WO6/ZnO composite with visible light activity.The composite is characterized by X‐ray diffraction,transmission... The photocatalytic ability of ZnO is improved through the addition of flower‐like Bi2WO6 to prepare a Bi2WO6/ZnO composite with visible light activity.The composite is characterized by X‐ray diffraction,transmission electron microscopy,scanning electron microscopy with UV–vis diffuse reflectance spectroscopy,X‐ray photoelectron spectroscopy and N2 adsorption‐desorption isotherms.After modification,the band gap energy of Bi2WO6/ZnO is reduced from 3.2 eV for ZnO to 2.6 eV.Under visible light irradiation,the Bi2WO6/ZnO composite shows an excellent photocatalytic activity for degrading methylene blue(MB)and tetracycline.The photo‐degradation efficiencies of(0.3:1)Bi2WO6/ZnO for MB and tetracycline are approximately 246 and 4500 times higher than those of bare ZnO,respectively,and correspondingly,the photo‐degradation rates for the two pollutants are approximately 120 and 200 times higher than those with bare ZnO,respectively.Moreover,the photocatalyst of(0.3:1)Bi2WO6/ZnO exhibits a higher transient photocurrent density of approximately 4.5μA compared with those of bare Bi2WO6 and ZnO nanoparticles.The successful recombination of Bi2WO6 and ZnO enhances the photocatalytic activity and reduces the band gap energy of ZnO,which can be attributed to the effective separation of electron–hole pairs.Active species trapping experiments display that[O2]-is the major species involved during photocatalysis rather than·OH and h+.This study provides insight into designing a meaningful visible‐light‐driven photocatalyst for environmental remediation. 展开更多
关键词 Bismuth tungstate Zinc oxide PHOTOCATALYSIS Methylene blue ANTIBIOTICS
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The complete mitochondrial genome of Triuncina daii(Lepidoptera:Bombycidae) and its phylogenetic implications 被引量:1
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作者 Yipei ZHAO Xingshi GU +1 位作者 Gefeng REN Xing WANG 《Entomotaxonomia》 CSCD 2017年第3期223-237,共15页
The bombycid moth, Triuncina daii Xing Wang & Zolotuhin, 2015, plays an important role for analyzing the phylogenetic relationships of the family Bombycidae (Lepidoptera: Bombycoidea). Here we first describe the c... The bombycid moth, Triuncina daii Xing Wang & Zolotuhin, 2015, plays an important role for analyzing the phylogenetic relationships of the family Bombycidae (Lepidoptera: Bombycoidea). Here we first describe the complete mitochondrial genome (mitogenome) of T. daii, which includes thirteen protein-coding genes (PCGs), twenty-two transfer RNA genes, two ribosomal RNA genes and an A+T-rich region, and we find the mitogenome is 15,482 bp in length (GenBank no. KY091643). The genes order and orientation in the T. daii mitogenome are similar to other sequenced lepidopteran species. Except for cox1, all of the PCGs started with ATN. Twelve PCGs stopped at TAA except for cox1 which stops at a single T. Thirteen PCGs of available species are used to demonstrate the inner phylogenetic relationships of Bombycoidea. The bombycid species form a monophyletic clade with a bootstrap value of 100% and a posterior probability of 1.00. 展开更多
关键词 MITOGENOME Protein-coding genes cytochrome c oxidase subunit I (coxl) Nucleotidecomposition
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Effects of Magnetic Field on Photodegradation of Methylene Blue over ZnO and TiO2 Powders using UV-LED as a Light Source 被引量:1
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作者 Supawan Joonwichien Eiji Yamasue Hideyuki Okumura Keiichi Ishihara 《Journal of Chemistry and Chemical Engineering》 2011年第8期729-737,共9页
The magnetic field effects (MFEs) are studied on photocatalytic degradation of methylene blue (MB) solution using ZnO and TiO2 particles. The UV-VIS-NIR spectrometer is used to monitor the MB concentrations, and t... The magnetic field effects (MFEs) are studied on photocatalytic degradation of methylene blue (MB) solution using ZnO and TiO2 particles. The UV-VIS-NIR spectrometer is used to monitor the MB concentrations, and the dependence of the reaction rate on the initial dye concentration and settling duration is studied under UV light irradiation. It is found that the MFEs exist on the heterogeneous reaction systems for both ZnO and TiO2 powders and that the extraordinary phenomenon is reproducible. For ZnO powder, the results are in good agreement with the second-order reaction kinetics following the Langmuir-Hinshelwood (L-H) model, while the reaction for TiO2 follows first-order kinetics. It enhances the photodegradation for ZnO, while it reduces or enhances the reaction for TiO2 depending on the initial dye concentrations. The MFEs become small or negligible when the same photodecomposition experiment is carried out after settling the MB solution for more than three hours for both ZnO and TiO2. It is suggested that the key factors of MFEs on photocatalytic degradation is the condition of the MB solution as well as the characteristics of photocatalysts. The alteration of the MFEs ascribed to the solution condition caused by variation of the settling time. 展开更多
关键词 Magnetic field effect photocatalytic degradation Methylene blue ZNO TiO2
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Preparation of porous silica from natural chlorite via selective acid leaching and its application in methylene blue adsorption
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作者 WANG Zhi-zeng ZHAO Qin-yi +1 位作者 WANG Dong-yun CUI Chong 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第4期1173-1184,共12页
In this study,porous silica with high surface area was prepared through selective leaching of thermally activated chlorite in HCl solution.In the process,chlorite was activated by pre-calcining treatment,then activate... In this study,porous silica with high surface area was prepared through selective leaching of thermally activated chlorite in HCl solution.In the process,chlorite was activated by pre-calcining treatment,then activated components(MgO,Al_(2)O_(3),and Fe_(2)O_(3))were selectively leached by acid solution,resulting in the formation of nanopores in situ.The morphology,structure,surface area and pore-size distribution of the material were characterized by XRD,TG/DSC,^(27)Al MAS NMR,SEM,TEM and N2 adsorption−desorption isotherms.The highest specific surface area(SBET=333 m^(2)/g)was obtained by selectively leaching the 600℃ calcined chlorite from 3 mol/L HCl at 90℃ for 2 h.The pore sizes and specific surface areas can be controlled by calcination and leaching conditions.The ^(27)Al MAS NMR spectra of the samples revealed the relationship between structural transformation and the selective acid leaching properties of thermal-activated chlorite,demonstrating that AlVI transfers into AlV when chlorite changes into activated chlorite during thermal activation,and the coordinations of Al has a significant effect on acid solubility of chlorite.The as-prepared porous silica showed favorable adsorption abilities with capacity of 148.79 mg/g for methylene blue at pH of about 7 and temperature of 25℃,indicating its promising potential in adsorption application. 展开更多
关键词 CHLORITE thermally activated selective leaching porous silica materials methylene blue adsorption
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Cu_2O/SiC as efficient catalyst for Ullmann coupling of phenols with aryl halides 被引量:1
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作者 Yibing Wang Xiaoning Guo +3 位作者 Manqian Lü Zhaoyang Zhai Yingyong Wang Xiangyun Guo 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第4期658-664,共7页
A Cu2O/SiC heterogeneous catalyst was prepared via a two‐step liquid‐phase method using diethyleneglycol as both the solvent and the reducing agent.The catalyst was characterized using X‐raydiffraction,X‐ray photo... A Cu2O/SiC heterogeneous catalyst was prepared via a two‐step liquid‐phase method using diethyleneglycol as both the solvent and the reducing agent.The catalyst was characterized using X‐raydiffraction,X‐ray photoelectron spectroscopy,scanning electron microscopy(SEM),transmissionelectron microscopy(TEM),and H2temperature‐programmed reduction.All the results indicatethat Cu is present on the SiC support primarily as Cu2O.The SEM and TEM results show that cubicCu2O nanoparticles are uniformly dispersed on theβ‐SiC surface.The reaction conditions,namelythe temperature,reaction time,and amounts of base and catalyst used,for the Ullmann‐type C–Ocross‐coupling reaction were optimized.A model reaction was performed using iodobenzene(14.0mmol)and phenol(14.0mmol)with Cu2O/SiC(5wt%Cu)as the catalyst,Cs2CO3(1.0equiv.)as thebase,and tetrahydrofuran as the solvent at150°C for3h;a yield of97%was obtained and theturnover frequency(TOF)was1136h?1.The Cu2O/SiC catalyst has a broad substrate scope and canbe used in Ullmann‐type C–O cross‐coupling reactions of aryl halides and phenols bearing a varietyof different substituents.The catalyst also showed high activity in the Ullmann‐type C–Scross‐coupling of thiophenol with iodobenzene and substituted iodobenzenes;a TOF of1186h?1was achieved.The recyclability of the Cu2O/SiC catalyst in the O‐arylation of phenol with iodobenzenewas investigated under the optimum conditions.The yield decreased from97%to64%afterfive cycles.The main reason for the decrease in the catalyst activity is loss of the active component,i.e.,Cu2O. 展开更多
关键词 Cuprous oxide Silica carbide Ullmann coupling O‐arylation PHENOLS Aryl halide
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Selective aerobic oxidation promoted by highly efficient multi-nitroxy organocatalysts 被引量:1
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作者 Kexian Chen Haiying Xie 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第4期625-635,共11页
Selective oxidation with molecular oxygen as the sole oxidant under mild conditions is of crucialimportance for the long‐term sustainable exploitation of available feedstocks and the formation ofrequired intermediate... Selective oxidation with molecular oxygen as the sole oxidant under mild conditions is of crucialimportance for the long‐term sustainable exploitation of available feedstocks and the formation ofrequired intermediates for organic synthesis and industrial processes.Among the developed oxidationprotocols,innovative strategies using hydroxyimide organocatalysts in combination with metallicor metal‐free cocatalysts have attracted much attention because of the good activities andselectivities of such catalysts in the oxo functionalization of hydrocarbons.This method is based onthe reaction using N‐hydroxyphthalimide,which was first reported by Ishii’s group in the1990s.Although the important and wide‐ranging applications of such catalysts have been summarizedrecently,there are no reviews that focus solely on oxidation strategies using multi‐nitroxy organocatalysts,which have interesting properties and high reactivities.This review covers the concisesynthetic methods and mechanistic profiles of known multi‐nitroxy organocatalysts and summarizessignificant advances in their use in efficient aerobic oxidation.Based on a combination of experimentaland theoretical results,guidelines for the future rational design of multi‐nitroxy organocatalystsare proposed,and the properties of various model multi‐nitroxy organocatalysts are predicted.The present overview of the advantages,limitations,and potential applications of multi‐nitroxyorganocatalysts can provide useful tools for researchers in the field of selective oxidation. 展开更多
关键词 Molecular oxygen N‐hydroxyphthalimide ORGANOCATALYSIS Oxidation RADICAL
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Solubility of CO2 in Methanol, 1-Octyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide, and Their Mixtures 被引量:2
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作者 雷志刚 张本凤 +3 位作者 朱吉钦 宫万福 吕建宁 李延生 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第3期310-317,共8页
Solubility data of carbon dioxide (CO2) (1) in methanol (2), 1-octyl-3-methylimidazolium bis(trifluoro- methylsulfonyl)imide ([omim]+[TfzN]-) (3), and their mixtures (w3 = 0.2, 0.5, and 0.8) at temperat... Solubility data of carbon dioxide (CO2) (1) in methanol (2), 1-octyl-3-methylimidazolium bis(trifluoro- methylsulfonyl)imide ([omim]+[TfzN]-) (3), and their mixtures (w3 = 0.2, 0.5, and 0.8) at temperatures 313.2 and 333.2 K and pressures up to 7.0 MPa were measured by a high-pressure view-cell technique. The solubility of CO2 in methanol (w3 = 0), [omim]+[Tf2N]- (w3 = 1.0) and their mixtures follows the order of (w3 = 0)〈(w3 = 0.2)〈 (w3 = 0.5)〈(w3 = 0.8)〈(w3 = 1.0) at the same temperature and pressure, while the magnitude of Henry's constants follows the reverse order at a given temperature, which is consistent with the COSMO-RS (conductor-like screen- ing for real solvents) calculation. The solubility data of CO2 in methanol and [omim]~[Tf2N]- are correlated with the Peng-Robinson equation of state, and the solubility of CO2 in the mixtures of methanol and [omim]+[TfzN] can be well predicted based on the mole fraction average of methanol and [omim]+[Tf2N] over the solubility of CO2 in pure methanol and [omim]+[Tf2N] . The mixtures of methanol and [omim]+[Tf2N]- may be used as physical solvents for capturing CO2 with high partial pressures since they combine the advantages of organic solvents and ionic liquids. 展开更多
关键词 CO2 SOLUBILITY METHANOL ionic liquids Peng-Robinson equation of state
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Electrocatalytic Oxidation of Calcium Folinate on Carboxyl Graphene Modified CuxO/Cu Electrode 被引量:2
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作者 Li-wen Wang Shou-guo Wu +2 位作者 Tian-yang Shi Wei Wei Pan Pan 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第6期729-734,I0002,共7页
Carboxyl graphene modified CuxO/Cu electrode was fabricated. The bare copper electrode was firstly anodic polarized in 1.0 mol/L NaOH solution in order to get CuxO nanoparticles, then the carboxyl graphene (CG) was ... Carboxyl graphene modified CuxO/Cu electrode was fabricated. The bare copper electrode was firstly anodic polarized in 1.0 mol/L NaOH solution in order to get CuxO nanoparticles, then the carboxyl graphene (CG) was electrodeposited on the CuxO/Cu electrode by cyclic potential sweeping. The electrocatalytic oxidation behaviors of calcium folinate (CF) at the graphene modified CuxO/Cu electrode were investigated by cyclic voltammetry. A positive scan polarization reverse catalytic voltammetry was used to obtain the pure catalytic oxidation current. The graphene modified CuxO/Cu electrode was served as the electrochemical sensor of CF, a highly sensitivity of 22.0μA.(μmol/μL)^-1cm^-2 was achieved, and the current response was linear with increasing CF concentration in the range of 2.0×10^-7 mol/L to 2.0×10^-5 mol/L, which crossed three orders of magnitude, and the detection limit was found 7.6×10^-5 mol/L (S/N=3). In addition, the proposed sensor was successfully applied in determination of CF in drug sample. 展开更多
关键词 Calcium folinate Carboxyl graphene CuxO/Cu electrode Chemically modi-fied electrode Positive scan polarization reverse catalytic voltammetry
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Crystal and Molecular Structure of Methylene-bis[benzobicyclo(diaza-diphenyl) stannoxide],[o-O■n(C_6H_5)_2]_2CH_2·1/2C_6H_6
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作者 王积涛 高生华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1994年第2期91-94,共4页
Methylene-bis[benzobicyclo(diaza-diphenyl) stannoxide,C_(41)H_(34)N_4O_4Sn_2·1/2C_6H_6],Mr=923.19,m.p.126-127℃,triclinic,P1,a=9.780(4),b=14.485(2),c=15.122(6),α=74. 95(3),β=72.21(3),γ=82.68(2)°,V=1967(1)... Methylene-bis[benzobicyclo(diaza-diphenyl) stannoxide,C_(41)H_(34)N_4O_4Sn_2·1/2C_6H_6],Mr=923.19,m.p.126-127℃,triclinic,P1,a=9.780(4),b=14.485(2),c=15.122(6),α=74. 95(3),β=72.21(3),γ=82.68(2)°,V=1967(1) Z=2,Dx=1.56 g/cm ̄3, MoKα(λ=0.71073),μ=13.20 cm-1,F(000)=922;final R=0.045, Rw=0.046 for 3637 observed reflections(I≥3σ(I)).The title compound is a bimetallo-heterocyclic complex prepared by condensation.Each tin atom has a trigonal bipyramidal coordination with two oxygen atoms occupying the axial positions. 展开更多
关键词 crystal structure bimetallic complex five-coordinated-tin complex
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Differential expression of genes encoding sulfur metabolism-related periplasmic proteins of Acidithiobacillus ferrooxidans ATCC 23270
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作者 夏金兰 张瑞永 +4 位作者 张倩 武顺 张成桂 聂珍媛 邱冠周 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第12期2366-2370,共5页
Reverse-transcription qualitative PCR(RT-qPCR)was used to analyze the changes in transcription levels of the sulfur metabolism-related periplasmic protein genes of Acidithiobacillus ferrooxidans ATCC 23270 grown on su... Reverse-transcription qualitative PCR(RT-qPCR)was used to analyze the changes in transcription levels of the sulfur metabolism-related periplasmic protein genes of Acidithiobacillus ferrooxidans ATCC 23270 grown on sulfur or ferrous.Seven periplasmic proteins with apparently higher abundance grown on elemental sulfur than on ferrous sulfate were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF-MS).Expression analysis of the corresponding genes by RT-qPCR shows that the constitutive expression of all those genes are more up-regulated grown on sulfur than those grown on ferrous(>10 folder).Study on the corresponding genes of the identified periplasmic proteins by RT-qPCR confirmed the results of two-dimensioned gel electrophoresis,indicating they may be related with sulfur metabolism in A.ferrooxidans. 展开更多
关键词 Acidithiobacillus ferrooxidans RT-QPCR periplasmic proteins
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Optimization of Fermentation Media for Enhancing Nitrite-oxidizing Activity by Artificial Neural Network Coupling Genetic Algorithm 被引量:2
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作者 罗剑飞 林炜铁 +1 位作者 蔡小龙 李敬源 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第5期950-957,共8页
Two artificial intelligence techniques, artificial neural network and genetic algorithm, were applied to optimize the fermentation medium for improving the nitrite oxidization rate of nitrite oxidizing bacteria. Exper... Two artificial intelligence techniques, artificial neural network and genetic algorithm, were applied to optimize the fermentation medium for improving the nitrite oxidization rate of nitrite oxidizing bacteria. Experiments were conducted with the composition of medium components obtained by genetic algorithm, and the experimental data were used to build a BP (back propagation) neural network model. The concentrations of six medium components were used as input vectors, and the nitrite oxidization rate was used as output vector of the model. The BP neural network model was used as the objective function of genetic algorithm to find the optimum medium composition for the maximum nitrite oxidization rate. The maximum nitrite oxidization rate was 0.952 g 2 NO-2-N·(g MLSS)-1·d-1 , obtained at the genetic algorithm optimized concentration of medium components (g·L-1 ): NaCl 0.58, MgSO 4 ·7H 2 O 0.14, FeSO 4 ·7H 2 O 0.141, KH 2 PO 4 0.8485, NaNO 2 2.52, and NaHCO 3 3.613. Validation experiments suggest that the experimental results are consistent with the best result predicted by the model. A scale-up experiment shows that the nitrite degraded completely after 34 h when cultured in the optimum medium, which is 10 h less than that cultured in the initial medium. 展开更多
关键词 BP neural network genetic algorithm OPTIMIZATION nitrite oxidization rate nitrite-oxidizing bacteria
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Photocatalytic Degradation of Methylene Blue with Side-glowing Optical Fiber Deliverying Visible Light
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作者 储金宇 仲蕾 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第5期895-899,共5页
The side-glowing optical fibers (SOFs) were chosen as the conducting medium of endogenous light; and 20 mg·L-1 methylene blue was chosen as the target to be degraded. The SOF is made up of quartz core with a sili... The side-glowing optical fibers (SOFs) were chosen as the conducting medium of endogenous light; and 20 mg·L-1 methylene blue was chosen as the target to be degraded. The SOF is made up of quartz core with a silicon cladding, which can emit light through side surface more uniformly and transmit light for longer distance to avoid attenuation of light by liquid medium. The filament lamp was chosen as visible light source. Different reaction conditions, such as the presence of optical fiber or not, the quantity of SOF, light irradiation intensity were tested by measuring the methylene blue degradation of methylene blue. The results show that suitable reaction conditions were 1.167 g·L-1 Ag + /TiO 2 with 7% (by mass) of Ag + doped in TiO 2 , and 500 roots of SOF (30 cm length in solution). The photocatalytic degradation efficiency under 300W lamp irradiation for 8h was about 97%. And the photocatalytic degradation efficiency of methylene blue degradation was proportional to SOF quantity, light irradiation intensity and catalytic dosage within a certain range. Compared with general UV and visible light SOFs could save a huge amount of energy and cost, in the potential applications in dealing with organic pollutants on a large scale. 展开更多
关键词 side-glowing optical fiber visible light PHOTOCATALYSIS Ag+/TiO2 catalyst methylene blue
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Influence of Inorganic Salts during the Photooxidative Process of Nitrobenzene
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作者 Fernando Hernandez Aldana Antonio Rivera +4 位作者 Miguel Angel Hernandez Eduardo Torres Tonahtiuh Rendon Teresa Zayas Leticia Flores 《Journal of Environmental Science and Engineering(A)》 2013年第4期267-275,共9页
Into the photooxidation process, several factors such as pH, time of irradiation, dose of UV light, lamp power, contaminant concentration, turbidity of the solution and the presence of salts can interfere with the pho... Into the photooxidation process, several factors such as pH, time of irradiation, dose of UV light, lamp power, contaminant concentration, turbidity of the solution and the presence of salts can interfere with the photodegradation of pollutants. This research aims to evaluate the influence of salts: NaCl, MgCl2, CaCI2, BaC12, CuCl2, Na2SO4, MgSO4, MnSO4, FeSO4, CuSO4, Na3PO4, K2CrO4 and K2Cr207 in concentrations of 0.0005 M, 0.005 M and 0.05 M during photodegradation of aqueous solution of 59.5 mg/L of nitrobenzene at a pH of 2.5. It was observed that the presence of salts such as CuCI2, CuSO4, FeSO4, K2CrO4 and K2Cr207 interfere negatively in the system UV/H202 applied for degradation of nitrobenzene; possibly by oxidation of Fe2+ to Fe3+ and Cu+ to Cu2+ in the Cr case, due to the difficulty of transforming the Cr6+ to Cr3+ or because these solutions have color and act as radiation absorbing filter. 展开更多
关键词 AOPS nitrobenzene photooxidation influence by salts.
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动物类中药DNA条形码鉴定研究进展 被引量:17
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作者 王孟虎 许亮 +5 位作者 康廷国 常安 陈思有 何婉婉 李庆 郭爽 《中国实验方剂学杂志》 CAS CSCD 北大核心 2016年第15期227-234,共8页
DNA基因鉴定是近年来应用在中药鉴定中较为重要的分子生物技术,该技术能够很好地从基因层面上鉴别药材,具有较高的准确性。DNA基因鉴定包括DNA分子遗传标记,核酸探针杂交,DNA条形码分子鉴定法等,其中发展最快的为DNA条形码分子鉴定法。... DNA基因鉴定是近年来应用在中药鉴定中较为重要的分子生物技术,该技术能够很好地从基因层面上鉴别药材,具有较高的准确性。DNA基因鉴定包括DNA分子遗传标记,核酸探针杂交,DNA条形码分子鉴定法等,其中发展最快的为DNA条形码分子鉴定法。DNA条形码分子鉴定法是利用基因组中一段公认的、相对较短的DNA序列来进行物种鉴定的一种分子生物学技术,是传统形态鉴别方法的有效补充。由于不同物种的DNA序列是由腺嘌呤(A),鸟嘌呤(G),胞嘧啶(C),胸腺嘧啶(T)4种碱基以不同顺序排列组成,因此对某一特定DNA片段序列进行分析即能够区分不同物种。Hebert等在2003年提出了通过测定线粒体细胞色素C氧化亚基I(COI)基因序列来鉴定动物的种类。陈士林等则在大量实验的基础上提出了鉴别动物的基因以COI基因为主,ITS2基因为辅的动物类药材DNA条形码鉴定体系。大量的实验表明,通过DNA条形码来鉴别动物具有准确性、可行性、简便性、通用性,为鉴别动物物种及发现新物种提供了新的方法,为鉴别动物药材的真伪提供了科学的依据。但由于该技术是通过基因进行鉴定,对实验材料及提取方法有较高要求,对一些年代较久的动物药材,其DNA降解较为严重,为DNA提取技术提出了较高的要求;该技术只能鉴别其来源是否准确却不能鉴别其药用部位是否准确,这就需要结合其他鉴别方法来准确鉴别其药用部位。本文通过综合国内外对DNA条形码的研究,为日后的研究和应用提供理论依据。 展开更多
关键词 药用动物 DNA条形码 线粒体细胞色素C氧化亚基I
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