期刊文献+
共找到535篇文章
< 1 2 27 >
每页显示 20 50 100
定向引入N⁃糖基化位点促进芳基醇氧化酶热稳定性及底物亲和力
1
作者 曹查 朱作华 +3 位作者 龚文兵 周映君 谢纯良 彭源德 《食品研究与开发》 CAS 2024年第7期165-173,共9页
芳基醇氧化酶在木质素降解过程中发挥重要作用,N-糖基化修饰影响其酶学性质。该文旨在通过研究刺芹侧耳(Pleurotus eryngii)来源的芳基醇氧化酶N-糖基化,来提高其热稳定性和底物亲和力。利用毕赤酵母GS115表达系统和定点突变技术,构建表... 芳基醇氧化酶在木质素降解过程中发挥重要作用,N-糖基化修饰影响其酶学性质。该文旨在通过研究刺芹侧耳(Pleurotus eryngii)来源的芳基醇氧化酶N-糖基化,来提高其热稳定性和底物亲和力。利用毕赤酵母GS115表达系统和定点突变技术,构建表达6种芳基醇氧化酶突变体蛋白,并对纯化后的野生型和突变体酶进行酶学性质和热稳定性分析。结果表明,芳基醇氧化酶N89和N249糖基化位点突变导致最适温度和70℃时酶热稳定性降低;在这个过程中,将其引入新的糖基化位点后的突变体,其最适酸碱度没有变化,最适温度以及70℃下的热稳定程度都明显优于野生型;以藜芦醇为底物时,突变体[AAO(F-X-N-X-T)]与底物亲和力最高。N-糖基化主要影响芳醇氧化酶的热稳定性,其中N89和N249位点的N-糖基化对酶的热稳定性起重要作用;引入N-糖基化位点[AAO(F-X-N-X-T)]能获得具有高活力和高稳定性的芳醇氧化酶。 展开更多
关键词 芳基醇氧化酶 n-糖基化 定点突变 重组表达 酶学性质
下载PDF
Performance, Combustion and Emission Characteristics of Oxygenated Diesel in DI Engines: A Critical Review
2
作者 Joseph Lungu Lennox Siwale Rudolph Joe Kashinga 《Journal of Power and Energy Engineering》 2024年第6期16-49,共34页
The transition from non-renewable to renewable energy sources is a significant challenge of our time. In the fuel industry, oxygenated additives such as butanol are transforming conventional fuels into renewable biofu... The transition from non-renewable to renewable energy sources is a significant challenge of our time. In the fuel industry, oxygenated additives such as butanol are transforming conventional fuels into renewable biofuels. This technology has been utilized in reciprocating engines for decades. This paper reviews the viability of using an n-butanol blend as a short-term replacement for diesel by analyzing its physical and chemical properties, combustion, performance, and emission characteristics in compression ignition (CI) engines under various conditions, including variable load, speed, acceleration, and both stationary and transient cycles. N-Butanol exhibits higher viscosity, better lubricity, higher heating value, improved blend stability, enhanced cold-flow properties, and higher density. These factors influence spray formation, injection timing, atomization, and combustion characteristics. Its higher oxygen content improves the diffusion combustion stage and efficiency. Adding 5% and 10% n-butanol to diesel increases pressure and apparent heat release rate, slightly reduces temperature, and improves thermal efficiency, with mixed effects on CO and THC emissions and a notable decrease in particulate matter emissions. Fuel consumption increases, while the impact on NOx emissions varies. A 10% butanol blend is considered optimal for enhancing performance and reducing particulate emissions without significantly affecting NOx emissions. Blending up to 40% butanol with diesel does not require engine modifications or ECU recalibrations in engines calibrated for pure diesel. Due to its advantageous properties and performance, n-butanol is recommended as a superior alcohol-diesel blend than ethanol for short-term diesel replacement. 展开更多
关键词 Diesel Engine alcohol Additives n-BUTAnOL Combustion and Properties
下载PDF
Ni-Ce/N-rGO催化剂的表征及其催化苯酚加氢制备环己酮的性能 被引量:2
3
作者 徐海升 薛媚月 +2 位作者 黄国强 郜鹏程 范峥 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2023年第1期120-126,共7页
以鳞片石墨、尿素为原料,采用水热法制备了氮掺杂还原氧化石墨烯(N-rGO)载体,然后采用浸渍法制备了不同碱性组分改性的Ni/N-rGO催化剂,将其用于苯酚选择性加氢制备环己酮的反应。并通过N_(2)吸附-脱附、XRD、FT-IR、SEM和EDS等手段对Ni/... 以鳞片石墨、尿素为原料,采用水热法制备了氮掺杂还原氧化石墨烯(N-rGO)载体,然后采用浸渍法制备了不同碱性组分改性的Ni/N-rGO催化剂,将其用于苯酚选择性加氢制备环己酮的反应。并通过N_(2)吸附-脱附、XRD、FT-IR、SEM和EDS等手段对Ni/N-rGO催化剂进行表征。结果表明:与添加Cu、Fe、Na组分相比,添加组分Ce后Ni/N-rGO催化剂的比表面积和孔径均显著增大,可有效促进金属Ni在载体表面均匀分散,提高催化剂的活性;组分Ce的添加减弱了石墨烯表面含氧官能团的酸性质,有利于提高环己酮的选择性;在反应温度150℃、反应压力0.4 MPa、反应时间2.0 h、催化剂用量0.2 g的条件下,Ce/Ni摩尔比0.2时制备的Ni-Ce/N-rGO催化剂作用下,苯酚转化率为95.2%,环己酮选择性为72.6%。 展开更多
关键词 苯酚 ni-Ce/n-rGO催化剂 石墨烯 环己酮 环己烯醇
下载PDF
N-acetylcysteine attenuates oxidative stress and liver pathology in rats with non-alcoholic steatohepatitis 被引量:2
4
作者 Duangporn Thong-Ngam Suchittra Samuhasaneeto +1 位作者 Onanong Kulaputana Naruemon Klaikeaw 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第38期5127-5132,共6页
AIM: To evaluate attenuating properties of N-acetylcysteine (NAC) on oxidative stress and liver pathology in rats with non-alcoholic steatohepatitis (NASH). METHODS: Male Sprague-Dawley rats were randomly divided into... AIM: To evaluate attenuating properties of N-acetylcysteine (NAC) on oxidative stress and liver pathology in rats with non-alcoholic steatohepatitis (NASH). METHODS: Male Sprague-Dawley rats were randomly divided into three groups. Group 1 (control, n = 8) was free accessed to regular dry rat chow (RC) for 6 wk. Group 2 (NASH, n = 8) was fed with 100% fat diet for 6 wk. Group 3 (NASH + NAC20, n = 9) was fed with 100% fat diet plus 20 mg/kg per day of NAC orally for 6 wk. All rats were sacrificed to collect blood and liver samples at the end of the study. RESULTS: The levels of total glutathione (GSH) and hepatic malondialdehyde (MDA) were increased significantly in the NASH group as compared with the control group (GSH; 2066.7 ± 93.2 vs 1337.5 ± 31.5 μmol/L and MDA; 209.9± 43.9 vs 3.8 ±1.7 μmol/g protein, respectively, P < 0.05). Liver histopathology from group 2 showed moderate to severe macrovesicular steatosis, hepatocyte ballooning, and necroinflammation. NAC treatment improved the level of GSH (1394.8 ± 81.2 μmol/L, P < 0.05), it did not affect MDA (150.1 ± 27.0 μmol/g protein), but led to a decrease in fat deposition and necroinflammation. CONCLUSION: NAC treatment could attenuate oxidative stress and improve liver histology in rats with NASH. 展开更多
关键词 乙酰半胱氨酸氮 氧化作用 非酒精性脂肪肝 动物模型
下载PDF
2,4,6-Trichloro-1,3,5-triazine/dimethylformamide as an efficient reagent for one-pot conversion of alcohols into N-alkylphthalimides 被引量:3
5
作者 Babak Mokhtari Roya Azadi Aseieh Azhdari 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第2期171-174,共4页
An efficient and mild method for the direct conversion of alcohols into N-alkylphthalimides using 2,4,6-trichloro-1,3,5-triazine and dimethylformamide was described.The reaction was preceded via(alcoxymethylene) dimet... An efficient and mild method for the direct conversion of alcohols into N-alkylphthalimides using 2,4,6-trichloro-1,3,5-triazine and dimethylformamide was described.The reaction was preceded via(alcoxymethylene) dimethylammonium chloride intermediate and produced corresponding N-alkylphthalimides in good-to-excellent yields. 展开更多
关键词 alcohol Potassium phthalimide 2 4 6-Trichloro-1 3 5-triazine DIMETHYLFORMAMIDE n-alkylphthalimide
下载PDF
A Mild and Efficient Oxidation of Alcohols in Water 被引量:1
6
作者 ChuanZhiXU LinCHEN ZhenLI WeiSUN ChunGuXIA 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第10期1149-1152,共4页
关键词 OXIDATIOn alcoholS n-Bu4nBr PhI(OAc)2 water.
下载PDF
SYNTHESIS OF POLYMER-STABILIZED RUTHENIUM COLLOIDS BY LOW BOILING POINT ALCOHOL REDUCTION 被引量:2
7
作者 刘汉范 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第1期1-4,共4页
Stable and well-dispersed poly(N-vinyl-2-pyrrolidone) (PVP)-stabilized ruthenium colloidal clusters wereprepaxed via the reduction of ruthenium(III) chloride by refluxing with low boiling point alcohols. Investigation... Stable and well-dispersed poly(N-vinyl-2-pyrrolidone) (PVP)-stabilized ruthenium colloidal clusters wereprepaxed via the reduction of ruthenium(III) chloride by refluxing with low boiling point alcohols. Investigation of the size ofRu colloids by transmission electron microscopy (TEM) indicated that the average diametes could be controlled in the rangeof 1.2-1.6 nm with relative standard deviations of less than 0.33 by changing the molar ratio of PVP to Ru. The X-rayphotoelectron spectroscopy (XPS) characterization verified the formation of elemental ruthenium colloids. 展开更多
关键词 Polymer-stabilized colloid Poly(n-vinyl-2-pyrrolidone) RUTHEnIUM alcohol reduction
下载PDF
Indirect determination of cefradine with n-propyl alcohol-ammonium sulfate-water system by extraction-flotation of cuprous thiocyanate 被引量:1
8
作者 Ling Li Wu Wei Zhao Quan Min Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第5期565-568,共4页
A new method was developed for the determination of cefradine by extraction-flotation of CuSCN. The experiment indicated that in the presence of 0.20 mol/L NaOH the degradation of cefradine took place in water bath at... A new method was developed for the determination of cefradine by extraction-flotation of CuSCN. The experiment indicated that in the presence of 0.20 mol/L NaOH the degradation of cefradine took place in water bath at 100 ℃. The thiol group (-SH) of the degradation product could reduce Cu(Ⅱ) to Cu(Ⅰ) for the formation of the emulsion CuSCN in the presence of NH4SCN at pH 4.0. By determining the residual amount of Cu(Ⅱ) in the solution and calculating the flotation yield of Cu(Ⅱ), the indirect determination of cefradine can be obtained. This method has been applied to determine cefradine in capsules, human serum and urine samples, respectively. 展开更多
关键词 CEFRADInE Copper(Ⅱ) n-Propyl alcohol EXTRACTIOn-FLOTATIOn
下载PDF
Solvent extraction and separation of cobalt from leachate of spent lithium-ion battery cathodes with N263 in nitrite media 被引量:3
9
作者 Yingnan Yang Yingjie Yang +5 位作者 Chunlin He Yuezhou Wei Toyohisa Fujita Guifang Wang Shaojian Ma Wenchao Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第5期897-907,共11页
To effectively separate and recover Co(Ⅱ) from the leachate of spent lithium-ion battery cathodes,we investigated solvent extraction with quaternary ammonium salt N263 in the sodium nitrite system.NO_(2)^(-)combines ... To effectively separate and recover Co(Ⅱ) from the leachate of spent lithium-ion battery cathodes,we investigated solvent extraction with quaternary ammonium salt N263 in the sodium nitrite system.NO_(2)^(-)combines with Co(Ⅱ) to form an anion [Co(NO_(2))_(3)]^(-),and it is then extracted by N263.The extraction of Co(Ⅱ) is related to the concentration of NO_(2)^(-).The extraction efficiency of Co(Ⅱ) reaches the maximum of99.16%,while the extraction efficiencies of Ni(Ⅱ),Mn(Ⅱ),and Li(Ⅰ) are 9.27%-9.80% under the following conditions:30vol% of N263 and15vol% of iso-propyl alcohol in sulfonated kerosene,the volume ratio of the aqueous-to-organic phase is 2:1,the extraction time is 30 min,and1 M sodium nitrite in 0.1 MHNO_(3).The theoretical stages require for the Co(Ⅱ) extraction are performed in the McCabe–Thiele diagram,and the extraction efficiency of Co(Ⅱ) reaches more than 99.00% after three-stage counter-current extraction with Co(Ⅱ) concentration of 2544mg/L.When the HCl concentration is 1.5 M,the volume ratio of the aqueous-to-organic phase is 1:1,the back-extraction efficiency of Co(Ⅱ)achieves 91.41%.After five extraction and back-extraction cycles,the Co(Ⅱ) extraction efficiency can still reach 93.89%.The Co(Ⅱ) extraction efficiency in the actual leaching solution reaches 100%. 展开更多
关键词 COBALT n263 sodium nitrite EXTRACTIOn iso-propyl alcohol spent lithium-ion battery
下载PDF
Synthesis and Characterization of Hydrogels Based on Potato Starch/Poly(vinyl Alcohol)/N,N′-Methylenebisacrylamide
10
作者 Diego David Pinzón-Moreno Eder Clidio Vicuña-Galindo +2 位作者 JoséVulfrano González-Fernández JoséLuis Soto-Gonzales María Verónica Carranza-Oropeza 《Journal of Renewable Materials》 SCIE EI 2022年第8期2179-2201,共23页
Several hydrogels were synthesized by free-radical polymerization in an aqueous medium based on potato starch(PS),poly(vinyl alcohol)(PVA),and N,N′-Methylenebisacrylamide(MBAm),being possible to study these hydrogels... Several hydrogels were synthesized by free-radical polymerization in an aqueous medium based on potato starch(PS),poly(vinyl alcohol)(PVA),and N,N′-Methylenebisacrylamide(MBAm),being possible to study these hydrogels as a function of the proportion of components incorporated.In this way,the products generated from the synthesis were characterized by swelling and deswelling kinetics,the first swelling being verified with Schott and statistical models,allowing to contrast the proximity between the experimental and theoretical behavior.Additionally,water retention in soil(R%),spectroscopy(FTIR),morphological(SEM),and thermal(TGA and DSC)analysis allowing to know the intrinsic characteristics of the material,increasing in general terms the knowledge of this type of material.In this context,it was possible to verify the characteristics and effectiveness of the synthesis and crosslinking of the main components.The experimental results obtained show that the synthesized hydrogels present representative swellings consistent with kinetic and statistical models,optimal thermal stability depending on the amount of crosslinker,and excellent water retention in environments such as soil,presenting it as an excellent alternative to be used in agro-industrial applications in an eco-friendly way. 展开更多
关键词 HYDROGEL potato starch polyvinyl alcohol n n′-Methylenebisacrylamide kinetic swelling and deswelling water retention thermal characterization morphology characterization
下载PDF
超声心动图联合血浆NT-proBNP检测对酒精依赖性肝硬化患者心功能不全的诊断价值
11
作者 薛雪 高勤 赵晟 《肝脏》 2023年第7期767-771,共5页
目的研究超声心动图联合血浆N末端B型利钠肽原(NT-proBNP)检测对酒精依赖性肝硬化患者心功能不全(CIS)的诊断价值。方法选取2020年5月至2022年5月阜阳市第三人民医院酒精依赖性肝硬化患者79例,其中CIS组17例,非CIS组62例,均行超声心动... 目的研究超声心动图联合血浆N末端B型利钠肽原(NT-proBNP)检测对酒精依赖性肝硬化患者心功能不全(CIS)的诊断价值。方法选取2020年5月至2022年5月阜阳市第三人民医院酒精依赖性肝硬化患者79例,其中CIS组17例,非CIS组62例,均行超声心动图检查,检测NT-proBNP。对比两组临床资料、Tei指数及NT-proBNP,分析CIS发生的影响因素及Tei指数联合NT-proBNP对CIS的诊断价值。结果CIS组肝硬化病程(3.12±0.40)年、肝硬化分级C级10/17例、AST(79.23±8.92)U/L、ALT(68.52±9.21)U/L,高于非CIS组(2.44±0.35)年、16.13%(10/62)、(58.25±6.23)U/L、(51.28±7.10)U/L(P<0.05)。CIS组Tei指数(0.59±0.16)、血浆NT-proBNP水平(251.36±39.47)pg/mL,高于非CIS组(0.48±0.11)、(178.25±30.19)pg/mL(P<0.05)。经logistic回归分析,肝硬化病程、肝硬化分级、Tei指数、血浆NT-proBNP水平均为CIS发生的影响因素(P<0.05);经受试者工作特征曲线下面积(AUC)分析,Tei指数、NT-proBNP诊断酒精依赖性肝硬化患者CIS发生的Cut-off值为0.54、227.42 U/mL,AUC为0.873、0.750,Tei指数联合NT-proBNP预测的AUC为0.932。结论超声心动图联合血浆NT-proBNP对酒精依赖性肝硬化患者发生CIS具有较高诊断价值。 展开更多
关键词 超声心动图 n末端B型利钠肽原 酒精依赖性肝硬化 心功能不全
下载PDF
负载型贵金属催化剂Pt/N-COPs催化肉桂醛选择性加氢制备肉桂醇
12
作者 李立军 彭俊文 +2 位作者 杨钰玲 李安 朱政斌 《湖南理工学院学报(自然科学版)》 CAS 2023年第2期46-49,80,共5页
以Pt/N-COPs为催化剂,催化肉桂醛选择性加氢制备肉桂醇.采用三聚氰胺和三聚氰氯为原料,通过Buchwald-Hartwig反应合成含有三嗪环的共价有机聚合物,通过浸渍负载Pt制备Pt/N-COPs催化剂,用XRD、FT-IR和BET对其进行表征.结果表明,载体的富... 以Pt/N-COPs为催化剂,催化肉桂醛选择性加氢制备肉桂醇.采用三聚氰胺和三聚氰氯为原料,通过Buchwald-Hartwig反应合成含有三嗪环的共价有机聚合物,通过浸渍负载Pt制备Pt/N-COPs催化剂,用XRD、FT-IR和BET对其进行表征.结果表明,载体的富电子可以促进Pt很好分散在载体上.在肉桂醛选择性加氢制备肉桂醇的反应中,对催化剂的催化活性、动力学行为进行评价.结果表明,Pt/N-COPs催化剂不仅表现出优异的催化活性,而且表现出优异的C=O键加氢选择性. 展开更多
关键词 Pt/n-COPs 选择性加氢 肉桂醛 肉桂醇
下载PDF
Electro-spinning Antimicrobial N-halamine Modified Poly(vinyl alcohol)Nanofibers
13
作者 姜潜远 任学宏 黄东时 《Journal of Donghua University(English Edition)》 EI CAS 2014年第1期44-49,共6页
Antimicrobial poly( vinyl alcohol)( PVA) nanofibrous composites were prepared by adding 3-( 2,3-dihydroxypropyl)-5,5-dimethylimidazolidine-2,4-dione( N-halamine diol) to the PVA solution using electro-spinning techniq... Antimicrobial poly( vinyl alcohol)( PVA) nanofibrous composites were prepared by adding 3-( 2,3-dihydroxypropyl)-5,5-dimethylimidazolidine-2,4-dione( N-halamine diol) to the PVA solution using electro-spinning technique upon curing and exposure to diluted sodium hypochlorite. Scanning electron microscopy( SEM) demonstrates that PVA nanofibers formed with diameters of( 255 ±94) nm. Cross-linked PVA nanofibers with N-halamine diol precursor and 1,2,3,4-butanetetracarboxylic( BTCA) showed good water resistance. The chlorinated PVA nanofibrous mats completely inactivated Staphylococcus aureus( Gram-positive) and Escherichia coli O157: H7( Gram-negative) with 7 log reductions( the reduction of the bacterial concentration in logarithm) within 5min and 1 min of contact time,respectively. 展开更多
关键词 poly(vinyl alcohol)(PVA) AnTIMICROBIAL nAnOFIBER electro-spinning n-HALAMInE
下载PDF
C/N比对嗜酸细菌X-29产氢能力及其酶活性的影响 被引量:23
14
作者 李秋波 邢德峰 +2 位作者 任南琪 赵丽华 宋业颖 《环境科学》 EI CAS CSCD 北大核心 2006年第4期810-814,共5页
C/N比影响细菌的物质和能量代谢,为了提高产氢细菌的产氢效能,通过间歇产氢实验和酶活性分析方法,分析了在不同C/N比下嗜酸产氢细菌X-29的产氢能力以及氢化酶和乙醇脱氢酶的活性表达情况.研究结果表明,C/N比对产氢细菌的代谢及其相关酶... C/N比影响细菌的物质和能量代谢,为了提高产氢细菌的产氢效能,通过间歇产氢实验和酶活性分析方法,分析了在不同C/N比下嗜酸产氢细菌X-29的产氢能力以及氢化酶和乙醇脱氢酶的活性表达情况.研究结果表明,C/N比对产氢细菌的代谢及其相关酶的表达有显著的影响.虽然在不同C/N比下单位生物量的液相末端发酵产物差异不大,但是产氢能力存在显著的差异,当C/N比为14时产氢细菌X-29具有最大累积产氢量2 210.9mL/g.在不同C/N比下氢化酶的表达活性不同,氢化酶活性随着发酵的进行达到高峰后迅速降低,氢化酶的表达周期较短.乙醇脱氢酶活性随着代谢进程逐渐升高后而趋于平稳,不同C/N比时表达活性差异较小,表达周期较长.在C/N比为14时,氢化酶和乙醇脱氢酶的活性最高,分别为2.8μmol.(min.mg)-1和33.2μmol.(min.mg)-1. 展开更多
关键词 C/n 产氢细菌 氢化酶 乙醇脱氢酶 酶活性
下载PDF
预辐照聚乙烯醇纤维与N,N’-亚甲基双丙烯酸酰胺的接枝、交联 被引量:3
15
作者 张万喜 张长春 +3 位作者 孙国恩 董文飞 于黎 石洪皋 《应用化学》 CAS CSCD 北大核心 2002年第1期61-65,共5页
在缓冲溶液和亚铁离子存在下 ,辐照后的聚乙烯醇 ( PVA)纤维和 N ,N -亚甲基双丙烯酸酰胺 ( N ,N -MBAA)发生接枝、交联反应 .研究了单体浓度、单体和聚合物质量比、亚铁离子浓度、p H值、温度、时间对接枝率的影响 .结果表明 ,适... 在缓冲溶液和亚铁离子存在下 ,辐照后的聚乙烯醇 ( PVA)纤维和 N ,N -亚甲基双丙烯酸酰胺 ( N ,N -MBAA)发生接枝、交联反应 .研究了单体浓度、单体和聚合物质量比、亚铁离子浓度、p H值、温度、时间对接枝率的影响 .结果表明 ,适合于提高 PVA纤维的耐热软化点的接枝率为 1 5 %~ 2 0 % ,较佳的工艺条件为 :亚铁离子浓度为 0 .0 0 1 mol/L ,单体浓度大于 2 .5 g/d L,单体和聚合物的质量比 ( m ( N ,N -MBAA) /m( PVA) )大于 0 .4 ,p H值 3.4 ,接枝温度 80℃ ,接枝反应时间 1 5~ 30 min. 展开更多
关键词 聚乙烯醇纤维 n n′-亚甲基双丙烯酸酰胺 接枝共聚 交联 辐照 钴60 PVA纤维 改性 耐热水性能
下载PDF
富N条件下白腐菌对联苯的降解 被引量:10
16
作者 林鹿 邓耀杰 +1 位作者 胡健 詹怀宇 《应用与环境生物学报》 CAS CSCD 1999年第3期320-325,共6页
探讨了在富N条件下白腐菌降解芳香化合物酶的活性变化和对联苯的降解.研究结果表明,m(C)/m(N)比值对白腐菌的LiP和MnP活性有明显的影响;黎芦醇提高了LiP和MnP的活性及培养基中·OH基数量。
关键词 白腐菌 n 共代谢 联苯 降解
下载PDF
聚合物微球固载的N-羟基邻苯二甲酰亚胺在分子氧氧化苯甲醇反应过程中的催化特性 被引量:5
17
作者 杨晓林 黄建龙 +1 位作者 高保娇 门吉英 《化工学报》 EI CAS CSCD 北大核心 2015年第4期1318-1323,共6页
以甲基丙烯酸缩水甘油酯(GMA)和甲基丙烯酸甲酯(MMA)的交联共聚微球GMA/MMA为基质,经过几步大分子反应在微球表面合成与固载了N-羟基邻苯二甲酰亚胺(NHPI),形成固载有NHPI的聚合物微球GMA/MMA-NHPI。将GMA/MMA-NHPI与Co(OAc)2组成共催... 以甲基丙烯酸缩水甘油酯(GMA)和甲基丙烯酸甲酯(MMA)的交联共聚微球GMA/MMA为基质,经过几步大分子反应在微球表面合成与固载了N-羟基邻苯二甲酰亚胺(NHPI),形成固载有NHPI的聚合物微球GMA/MMA-NHPI。将GMA/MMA-NHPI与Co(OAc)2组成共催化体系,用于分子氧氧化苯甲醇的反应过程。研究结果表明,GMA/MMA-NHPI与Co(OAc)2所构成的共催化体系在温和条件(65℃和常压氧气)下可有效地实现苯甲醇的分子氧氧化过程,将其深度氧化为苯甲酸,显示出较好的催化活性和高的选择性(苯甲酸的选择性为96%)。主催化剂GMA/MMA-NHPI固载的NHPI与助催化剂Co(OAc)2适宜的摩尔比为20:1;主催化剂所含NHPI的摩尔分数为底物的10%时催化剂的用量比较适宜。固体催化剂GMA/MMA-NHPI还具有良好的再循环使用性能。 展开更多
关键词 n-羟基邻苯二甲酰亚胺 苯甲醇 氧化 催化 催化剂载体
下载PDF
醇+N-甲基哌嗪二元体系的体积性质 被引量:2
18
作者 陈树大 方文军 +1 位作者 雷群芳 林瑞森 《浙江大学学报(理学版)》 CAS CSCD 2002年第4期430-436,共7页
采用振荡管式数字密度计分别测定甲醇、乙醇、正丙醇、异丙醇、正丁醇和异丁醇与 N-甲基哌嗪组成的二元体系在 2 98.15 K下的密度 ,计算了超额摩尔体积、超额偏摩尔体积、表观摩尔体积、偏摩尔体积等体积性质 ,从分子相互作用角度讨论... 采用振荡管式数字密度计分别测定甲醇、乙醇、正丙醇、异丙醇、正丁醇和异丁醇与 N-甲基哌嗪组成的二元体系在 2 98.15 K下的密度 ,计算了超额摩尔体积、超额偏摩尔体积、表观摩尔体积、偏摩尔体积等体积性质 ,从分子相互作用角度讨论了这些二元体系的体积性质的变化规律 ,为 展开更多
关键词 n-甲基哌嗪 二元体系 体积性质 数字密度计 密度测量 超额摩尔体积 表观摩尔体积
下载PDF
N-乙酰半胱氨酸联合家蚕丝素蛋白解酒效果的动物试验 被引量:5
19
作者 陆旋 周兵 周晓红 《蚕业科学》 CAS CSCD 北大核心 2009年第3期675-679,共5页
为了开发解酒效果更好的蚕丝功能性食品,将具有氧自由基清除作用,易进入肝细胞的N-乙酰半胱氨酸添加入家蚕丝蛋白粉中,调查其对ICR种小鼠血液中乙醇的分解效果。N-乙酰半胱氨酸联合家蚕丝素蛋白灌胃处理较家蚕丝素蛋白灌胃处理对小鼠血... 为了开发解酒效果更好的蚕丝功能性食品,将具有氧自由基清除作用,易进入肝细胞的N-乙酰半胱氨酸添加入家蚕丝蛋白粉中,调查其对ICR种小鼠血液中乙醇的分解效果。N-乙酰半胱氨酸联合家蚕丝素蛋白灌胃处理较家蚕丝素蛋白灌胃处理对小鼠血液中的乙醇具有更好的分解效果:前者使小鼠血液中的乙醇浓度在灌胃乙醇30 min后就快速下降,至4 h时,小鼠血液中的乙醇浓度仅为对照组的8.1%;后者使小鼠血液中的乙醇浓度在灌胃乙醇120 min后开始下降,至4 h时,小鼠血液中的乙醇浓度为对照组的65.6%。N-乙酰半胱氨酸联合丝素蛋白对雌、雄ICR种小鼠和SD种大鼠的急性毒性试验结果显示,其LD50均大于10 g/kg,且在试验剂量范围(2.5、5.0、10.0 g/kg)内,对小鼠骨髓多染红细胞微核率及精子畸形发生率均未见有明显影响。在丝素蛋白粉中添加适量N-乙酰半胱氨酸后,能增强对供试动物血液中乙醇的分解作用,且无明显的毒副作用。 展开更多
关键词 n-乙酰半胱氨酸 丝素水解蛋白 实验动物 乙醇代谢 毒性
下载PDF
南海柳珊瑚Menella Spinifera Kukenthal化学成分的研究(一) 被引量:2
20
作者 邓松之 彭胜石 +2 位作者 李凤英 谈燮峰 程志飞 《广州化学》 CAS 1993年第4期44-47,共4页
从中国南海针小月柳珊瑚(Menella Spinifera Kukenthal)中分离到一种长链甘油醚,其结构经UV、IR、MS、~1H NMR、^(13)C NMR、~1H-~1H COSY以及元素分析确定为3—十八烷氧基—1,2—丙二醇鲨肝醇(Ⅰ)。本文是第一次报导它存在于该种属柳... 从中国南海针小月柳珊瑚(Menella Spinifera Kukenthal)中分离到一种长链甘油醚,其结构经UV、IR、MS、~1H NMR、^(13)C NMR、~1H-~1H COSY以及元素分析确定为3—十八烷氧基—1,2—丙二醇鲨肝醇(Ⅰ)。本文是第一次报导它存在于该种属柳珊瑚之中。 (Ⅰ) 展开更多
关键词 柳珊瑚 鲨肝醇 长链甘油醚
下载PDF
上一页 1 2 27 下一页 到第
使用帮助 返回顶部