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Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile
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作者 XU Jian-Qiang MA Zhao-Peng +2 位作者 CHENG Si LIU Zhi-Cong ZHU Guang-Lai 《原子与分子物理学报》 CAS 北大核心 2025年第4期27-32,共6页
The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this wo... The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this work.The following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution function.The results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient decreases.Additionally,the excess molar volume initially decreases,reaches a minimum,and then increases.The rules of radial distribution functions(RDFs)of characteristic atoms are different.With increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then decreases.This indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently. 展开更多
关键词 Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions
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Bonding Performance of Wood Treatment by Oxygen and Nitrogen Cold Plasma 被引量:2
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作者 王洪艳 杜官本 +2 位作者 郑荣波 王辉 李琴 《Agricultural Science & Technology》 CAS 2014年第3期392-394,443,共4页
In the test, woods were treated by N2, O2 cold plasma with the processing power 300 W, which last for 5 min; subsequently, the treated woods were bonded with MUF to valve the bonding performance, the contact angles of... In the test, woods were treated by N2, O2 cold plasma with the processing power 300 W, which last for 5 min; subsequently, the treated woods were bonded with MUF to valve the bonding performance, the contact angles of the treated/un- treated wood were tested. The chemical composition on the surface of wood with or without N2 cold plasma treatment was also studied by X-ray photoelectron spec- troscopy (XPS). The results showed: the contact angles of the surface decreased; the surface free energy increased evidently that treated by N2 or O2 cold plasma; the average bonding performance of wood that treated by cold plasma (whether N2 or O2) increased obviously and more than 50% was proved compared with that un- treated by cold plasma. The XPS analysis showed the atomic ratio O/C has in- creased, and more groups were oxidized or more peroxides were formed on the surface of wood; N element was introduced to the wood surface after nitrogen cold plasma treatment and it was estimated to the group of -NH2. 展开更多
关键词 Cold plasma Bonding performance Contact angle Surface energy
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Effects of Rhynchophylline on Guinea Pig Atria 被引量:1
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作者 陈长勋 金若敏 +1 位作者 王群 张海桂 《Journal of Chinese Pharmaceutical Sciences》 CAS 1995年第3期142-148,共7页
本实验观察钩藤碱对豚鼠左右心房的作用。对自发节律右心房,钩藤碱具有负性变时作用,此作用在15-200μmol/L范围内呈浓度效应依赖关系。对电驱动离体左心房,钩藤碱在浓度大于200μmol/L时产生负性肌力作用。20... 本实验观察钩藤碱对豚鼠左右心房的作用。对自发节律右心房,钩藤碱具有负性变时作用,此作用在15-200μmol/L范围内呈浓度效应依赖关系。对电驱动离体左心房,钩藤碱在浓度大于200μmol/L时产生负性肌力作用。200μmol/L钩藤碱使阈刺激波宽─强度曲线上移,表明心肌兴奋性下降。钩藤碱抑制肾上腺素诱发的心肌自律性,延长功能性不应期,显著抑制正阶梯现象。上述作用对抗心律失常有益,作用原理可能同其抑制钙内流有关。 展开更多
关键词 Rhynchophylline Isolated atria EXCITABILITY Functional refractory period StaircaseReceived April 12 1994 Accepted January 10 1995
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The Study of Dipivefrin Hydrochloride Ophthalmic Gel 被引量:1
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作者 王丽茹 张强 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第3期128-132,共5页
Dipivefrin hydrochloride ophthalmic gel was prepared and the release test and the isolated cornea permeation test of the formulation in vitro were investigated. The release test of the formulation was studied by using... Dipivefrin hydrochloride ophthalmic gel was prepared and the release test and the isolated cornea permeation test of the formulation in vitro were investigated. The release test of the formulation was studied by using permeable membrane. The content and the release amount of Dipivefrin hydrochloride from the gel base were measured by high performance liquid chromatography. The cornea permeation test of the formulation was studied by using isolated rabbit corneas. The formulation release behavior in vitro followed the first-order kinetic equation. The release amount of Dipivefrin hydrochloride raised significantly with less polymer in the formulation. The cornea permeation behavior of the drug in vitro followed the first-order kinetic equation. The eye irritancy of Dipivefrin hydrochloride gel is lower than that of eyedrops. 展开更多
关键词 Dipivefrin hydrochloride GEL HPMC Release in vitro HPLC Isolated cornea per-meation.
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Fabrication of an AlAs/In_(0.53)Ga_ ( 0.47)As/InAs Resonant Tunneling Diode on InP Substrate for High-Speed Circuit Applications
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作者 马龙 黄应龙 +3 位作者 张杨 王良臣 杨富华 曾一平 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第6期959-962,共4页
A high performance AlAs/In0.53 Ga0.47 As/InAs resonant tunneling diode (RTD) on InP substrate is fabricated by inductively coupled plasma etching. This RTD has a peak-to-valley current ratio (PVCR) of 7. 57 and a ... A high performance AlAs/In0.53 Ga0.47 As/InAs resonant tunneling diode (RTD) on InP substrate is fabricated by inductively coupled plasma etching. This RTD has a peak-to-valley current ratio (PVCR) of 7. 57 and a peak current density Jp = 39.08kA/cm^2 under forward bias at room temperature. Under reverse bias, the corresponding values are 7.93 and 34.56kA/cm^2 . A resistive cutoff frequency of 18.75GHz is obtained with the effect of a parasitic probe pad and wire. The slightly asymmetrical current-voltage characteristics with a nominally symmetrical structure are also discussed. 展开更多
关键词 resonant tunneling diode inductively coupled plasma current-voltage characteristics high frequency
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Surface plasmon resonance-induced visible-light photocatalytic performance of silver/silver molybdate composites 被引量:5
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作者 杨祥龙 王尹 +3 位作者 徐骁 瞿阳 丁星 陈浩 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期260-269,共10页
Novel silver/silver molybdate(Ag/Ag2MoO4) composites with surface plasmon resonance(SPR)-enhanced photocatalytic performance were successfully fabricated via a facile one-pot hydrothermal route with the presence o... Novel silver/silver molybdate(Ag/Ag2MoO4) composites with surface plasmon resonance(SPR)-enhanced photocatalytic performance were successfully fabricated via a facile one-pot hydrothermal route with the presence of sodium dodecyl sulfate(SDS) in this study.The as prepared silver/silver molybdate(Ag/Ag2MoO4) composites were systematically characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and ultraviolet-visible diffuse reflectance absorption spectroscopy(DRS) in order to investigate their crystal structure,morphology and optical property as well.The photocatalytic activities of the composites were subsequently evaluated by their ability to degrade rhodamine B(RhB) under visible-light irradiation.Varies of controlled experiments were then carefully operated to gain a deep insight into the assembling of Ag/Ag2MoO4composites.It was found that preparation conditions such as pH,reaction time,and the amount of surfactant played important roles in the formation of composites with octahedral microstructures.And the composite obtained at 160 ℃ using 0.5 g of sodium dodecyl sulfate exhibited the highest photocatalytic performance under visible-light irradiation.Capture experiments were also conducted to clarify the function of different active species generated on the surface of Ag/Ag2MoO4during the photocatalytic process,in which both holes and ·OH radicals were found to play crucial role in photocatalytic removal of RhB under visible light irradiation.A possible photocatalytic mechanism of Ag/Ag2MoO4 was finally proposed on the basis of all the results to explain the higher photocatalytic activity of the octahedral Ag/Ag2MoO4 composites.It was inferred that the photoinduced "hot" electrons can quickly transfer from the Ag NPs to the conduction band of Ag2MoO4 and react with oxygen and H2O to generate a large quality of active radicals such as ·OH and ·O2^- because of the SPR effects.Besides,this SPR effects of Ag nanoparticles deposited on the surface of Ag2MoO4 can not only dramatically amplify its light absorption,especially in the visible region,but also promote the separation of photoexcited electron-hole pairs and effectively decrease electron-hole recombination. 展开更多
关键词 SILVER Silver molybdate Sodium dodecyl sulfate Photocatalytic activity Surface plasmon resonance Rhodamine B
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Investigation of 980nm Ridge Waveguide Lasers with Current Non-Injection Regions by He Ion Implantaion 被引量:2
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作者 刘斌 张敬明 +1 位作者 马骁宇 肖建伟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第3期234-237,共4页
The technology of He ion implantation for improving the catastrophic optical damage (COD) level of 980nm semiconductor lasers is introduced.After He ion implantation,p-GaAs obtain higher resistivity than before.About... The technology of He ion implantation for improving the catastrophic optical damage (COD) level of 980nm semiconductor lasers is introduced.After He ion implantation,p-GaAs obtain higher resistivity than before.About 25μm-long current non-injection regions are introduced near both facets,where the injection current is blocked by high resistivity area.The current non-injection regions can reduce carriers inject to facets,and the rate of the non-radiative recombination are reduced.So the COD level is higher than before.The He ion implantation LDs exhibit no COD failure until the rollover occure at a mean maximum power of 440.5mW.Mean COD level of conventional LDs is given as 407.5mW.Compared to conventional LDs,the mean maximum output power level of He ion implantation LDs is improved by 8%. 展开更多
关键词 nm semiconductor lasers reliability He ion implantation non-injection regions COD
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Study on Capillary Zone Electrophoretic Separation of Chlorpheniramine Enantiomers with β-Cyclodextrin
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作者 李方 靳慧 +1 位作者 顾峻岭 傅若农 《Journal of Beijing Institute of Technology》 EI CAS 1997年第1期52-58,共7页
The chlorpheniramine enantiomers were separated with capillary zone electrophoresis using β-cyclodextrin as the chiral selector.The effects of the concentration of β-cyclodextrin, the electrolyte pH and organic modi... The chlorpheniramine enantiomers were separated with capillary zone electrophoresis using β-cyclodextrin as the chiral selector.The effects of the concentration of β-cyclodextrin, the electrolyte pH and organic modifier(urea) on the difference in apparent electrophoretic mobilities of the enantiomels were investigated. 展开更多
关键词 capillary zone electrophoresis ENANTIOSEPARATION ENANTIOMERS cydodextrin
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Tribological behaviors of Fe-Al-Cr-Nb alloyed layer deposited on 45 steel via double glow plasma surface metallurgy technique 被引量:2
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作者 罗西希 姚正军 +6 位作者 张平则 陈煜 杨红勤 吴小凤 张泽磊 林玉划 徐尚君 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3694-3699,共6页
Double glow plasma surface metallurgy technique was used to fabricate a Fe?Al?Cr?Nb alloyed layer onto the surface of the 45 steel. The microstructures and composition of th?eA Fl?eCr?Nb alloyed layer were analyzed by... Double glow plasma surface metallurgy technique was used to fabricate a Fe?Al?Cr?Nb alloyed layer onto the surface of the 45 steel. The microstructures and composition of th?eA Fl?eCr?Nb alloyed layer were analyzed by scanning electronic microscopy, X-ray diffraction and energy dispersive spectroscopy. The results indicate thatthe 20 μm alloyed layer is homogeneous and compact. The alloyed elements exhibit a gradient distribution along the cross section. Microhardness and nanoindentation tests imply that the surface hardness of the alloyed layer reaches HV 580, which is almost 2.8 times that of the substrate. Compared with the substrate, the alloyed layer has a much smaller displacement and a larger elastic modulus. According to the friction and wear tests at room temperature, the? FeAl?Cr?Nb alloyed layer has lower friction coefficient and less wear mass, implying that the Fe?Al?Cr?Nb alloyed layer can effectively improve the surface hardness and wear resistance of the substrate. 展开更多
关键词 Fe-Al-Cr-Nb alloyed layer double glow plasma surface metallurgy technique tribological behavior
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Enantioseparation of Several PharmaceuticalRacemates with High PerformanceCapillary electrophoresis
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作者 李方 靳慧 +2 位作者 戴荣继 顾峻岭 傅若农 《Journal of Beijing Institute of Technology》 EI CAS 1997年第3期239-243,共5页
With high performance capillary electrophoresis using -cyclodextrin or its deriveatives as the chiral selectors, five pairs of drug enantiomers were separated, The PH of the back- gmund electrolyte and the chiral sele... With high performance capillary electrophoresis using -cyclodextrin or its deriveatives as the chiral selectors, five pairs of drug enantiomers were separated, The PH of the back- gmund electrolyte and the chiral selector concentrations were optimized; and the effect of organic modifier on separation of chlorpheniramine enantiomers was also inver 展开更多
关键词 capillary electrophoresis ENANTIOSEPARATION chiral drugs
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Synthesis,characterization and photocatalytic performance of rod-shaped Pt/PbWO_4 composite microcrystals 被引量:6
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作者 余长林 白羽 +3 位作者 何洪波 范文宏 朱丽华 周晚琴 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第12期2178-2185,共8页
Rod-shaped PbW O4 microcrystals of length 1 μm were fabricated by a hydrothermal route and subsequent calcination. Pt nanoparticles(NPs) of different contents(0.5 wt%,1 wt% and 2 wt%) were subsequently deposited ... Rod-shaped PbW O4 microcrystals of length 1 μm were fabricated by a hydrothermal route and subsequent calcination. Pt nanoparticles(NPs) of different contents(0.5 wt%,1 wt% and 2 wt%) were subsequently deposited on the PbW O4 microcrystals,producing robust Pt/PbW O4 composite microcrystals. The PbW O4 microcrystals and Pt/PbW O4 photocatalysts were characterized by X-ray diffraction,N2 sorption measurements,scanning electron microscopy,transmission electron microscopy,and X-ray photoelectron,photoluminescence,Fourier-transform infrared,and ultraviolet-visible diffuse reflectance spectroscopies. The photocatalytic performances of the catalysts were evaluated by the consecutive photocatalytic degradation of acid orange II dye. The Pt/PbW O4 composite microcrystals exhibited high photocatalytic activity and stability. The deposition of Pt NPs produced surface plasmon resonance(SPR),which induced a large visible light absorption. A Pt NP content of 1-2 wt% resulted in an ~2 times increase in photocatalytic activity,compared with the activity of Pt/PbW O4. The crystal structure and high crystallinity of PbW O4 resulted in its favorable photocatalytic property,and the SPR effect of the Pt NPs promoted visible light harvesting. The Pt NPs also enhanced the separation of photo-generated electrons and holes,which further promoted the photocatalytic reaction. 展开更多
关键词 Rod-shaped Lead tungstate microcrystals Platium nanoparticles Photocatalytic activity Photocatalytic stability Surface plasma Electron-hole separation
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The Effect of pH on the Permeation of Lidocaine Hydrochloride Across Excised Rat Skin
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作者 贾士聪 丁平田 +2 位作者 郑俊民 吴翠栓 华士元 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第3期133-135,共3页
The effect of pH on the permeation of Lidocaine hydrochloride (LH) across excised rat skin was studied, the steady state flux (JSS) at different pH being determined using improved Valia-Chien diffusion cells. JSS incr... The effect of pH on the permeation of Lidocaine hydrochloride (LH) across excised rat skin was studied, the steady state flux (JSS) at different pH being determined using improved Valia-Chien diffusion cells. JSS increased substantially when pH was close to the pKa of LH. The profile of JSS versus pH showed an 慡?shaped curve. JSS of Lidocaine free base (LFB) was fourteen times that of LH. The pH of vehicle influences the permeation of LH significantly and should be considered as an important factor when a formulation is developed. 展开更多
关键词 PH PKA LIDOCAINE PERMEATION
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Acidthiobacillus ferrooxidans中磁小体的提取(英文) 被引量:12
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作者 谢建平 刘新星 +1 位作者 刘文斌 邱冠周 《生物磁学》 2005年第3期7-10,共4页
At.f和趋磁细菌在生理特性和生长环境有一定的相似性,而且镜检发现At.f具有趋磁性,所以本文采用了趋磁细菌中磁小体的提取方法尝试提取At.f中的磁小体,用超声波破碎At.f后,以磁铁吸取其体内的磁性颗粒,经过检测,发现其体内确实存在含铁... At.f和趋磁细菌在生理特性和生长环境有一定的相似性,而且镜检发现At.f具有趋磁性,所以本文采用了趋磁细菌中磁小体的提取方法尝试提取At.f中的磁小体,用超声波破碎At.f后,以磁铁吸取其体内的磁性颗粒,经过检测,发现其体内确实存在含铁元素的磁性颗粒。提取粗样品经过电镜分析,证实其体内存在着少量由脂质包裹的磁小体。磁小体悬浮液经过蔗糖密度梯度离心纯化后,对其作透射电镜,可以清晰的看到磁小体。实验结果表明,At.f体内存在少量的磁小体,正是由于磁小体的存在,才使得At.f在外加磁场作用下发生磁生物效应。这是首次发现从酸性矿坑水分离的At.f具有趋磁性,并从中提取到了磁小体,可以利用At.f的趋磁性将其按照不同磁性进行分离,从而获得活性高的、对不同磁性矿物有特异性的高效浸矿菌种。 展开更多
关键词 磁小体 提取方法 趋磁细菌 生长环境 磁性矿物 生物电磁学
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Ionic Conduction and Fuel Cell Performance of Ba0.98Ce0.8Tm0.2O3-α Ceramic
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作者 仇立干 王茂元 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第6期707-712,746,共7页
The perovskite-type oxide solid solution Ba0.98Ce0.8Tm0.2O3-α was prepared by high temperature solid-state reaction and its single phase character was confirmed by X-ray diffraction. The conduction property of the sa... The perovskite-type oxide solid solution Ba0.98Ce0.8Tm0.2O3-α was prepared by high temperature solid-state reaction and its single phase character was confirmed by X-ray diffraction. The conduction property of the sample was investigated by alternating current impedance spectroscopy and gas concentration cell methods under different gases atmospheres in the temperature range of 500-900 ℃. The performance of the hydrogen-air fuel cell using the sample as solid electrolyte was measured. In wet hydrogen, the sample is a pure protonic conductor with the protonic transport number of 1 in the range of 500-600 ℃, a mixed conductor of proton and electron with the protonic transport number of 0.945-0.933 above 600 ℃. In wet air, the sample is a mixed conductor of proton, oxide ion, and electronic hole. The protonic transport numbers are 0.010-0.021, and the oxide ionic transport numbers are 0.471-0.382. In hydrogen-air fuel cell, the sample is a mixed conductor of proton, oxide ion and electron, the ionic transport numbers are 0.942 0.885. The fuel cell using Ba0.98Ce0.8Tm0.2O3-α as solid electrolyte can work stably. At 900 ℃, the maximum power output density is 110,2 mW/cm2, which is higher than that of our previous cell using Ba0.98Ce0.8Tm0.2O3-α (x〈≤1, RE=Y, Eu, Ho) as solid electrolyte. 展开更多
关键词 Ba0.98Ce0.8Tm0.2O3-α Ionic conduction Gas concentration cell Alternating current impedance Fuel cell
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人体特异功能的特点及其生理基础探讨
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作者 宋孔智 《中国人体科学》 1995年第4期147-155,共9页
通过15年的工作,发现人体特异功能有一些重要的特点。物理特点为:离体性、距离效应、方向性、拓扑性;生理特点为:脑活动有序化程度提高、脑中出现屏幕感、体内出现特殊能量传递感、特异功能可以诱发和加强。
关键词 人体特异功能 离体性 距离效应 方向性 拓扑性
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Chemical Compositions and Antibacterial Activity of Essential Oil from Thymus Seedlings of Tissue Culture
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作者 徐世千 李晓东 张建国 《Agricultural Science & Technology》 CAS 2012年第6期1198-1202,共5页
[Objective] This study aimed to compare and analyze the chemical compositions, the relative contents and the antibacterial activity of the essential oils extracted from the tissue culture seedlings, the aseptic seedli... [Objective] This study aimed to compare and analyze the chemical compositions, the relative contents and the antibacterial activity of the essential oils extracted from the tissue culture seedlings, the aseptic seedlings and the common seedlings from seeds of Thymus vulgaris. [Method] The essential oil was extracted by steam distillation; the chemical compositions and their relative contents were analyzed by gas chromatography-mass spectrometry (GC/MS) and peak area normalization method; and the antimicrobial activity was tested by filter paper method. [Result] A total of 54 compositions were identified from these three samples, they had similar main compositions: thymol, m-Cymene, terpinene and so on, and these compositions were slightly different in contents. In addition, the essential oils from these three samples exhibited obvious antibacterial effect against Escherichia coli and Staphylococcus aureus, in which the antibacterial activity against S. aureus was stronger than against E. coli. [Conclusion] It is possible to produce essential oil by tissue culture technology; the main compositions and antibacterial activity of the oils remained almost the same. 展开更多
关键词 Tissue culture Thymus vulgaris Essential oil Antibacterial activity
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Optimization on Identification Standards and Artificial Inoculation Methods In Vitro on Resistance to Chrysanthemum White Rust
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作者 祝朋芳 赵妮拉 +2 位作者 齐丹 刘娜 段玉玺 《Agricultural Science & Technology》 CAS 2011年第11期1640-1644,共5页
[Objective] This research aimed at exploring an effective way for inoculation and identification of chrysanthemum white rust under controlled conditions. [Method] By combining the observation methods with the naked ey... [Objective] This research aimed at exploring an effective way for inoculation and identification of chrysanthemum white rust under controlled conditions. [Method] By combining the observation methods with the naked eye and under optical microscope, we had established the identification standards for chrysanthemum white rust with six classifications and optimized artificial inoculation methods in vitro. [Result] The results showed that bottled cuttings identification method and petri dished leaves identification method both can be used for identification in vitro of chrysanthemum white rust, bottled cuttings identification method had shown better effects than petri dished leaves identification method, and was supposed to be best artificial inoculation and identification method in vitro. [Conclusion] This research had provided a scientific method for safe and effective researches on chrysanthemum white rust, in order to control the occurrence and diffusion of this quarantine disease. 展开更多
关键词 Chrysanthemum white rust (CWR) Puccinia horiana Henn Identification standards In vitro Microscopy test
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New Alkylation Route of Benzene with Ethylene Catalyzed by [bmim]Cl/FeCl_3 Ionic Liquid 被引量:4
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作者 孙学文 赵锁奇 王仁安 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第5期658-661,共4页
Up to now the mechanism of Priedel-Crafts reactions catalyzed by ionic liquidhave not been fully understood, while carbocation mechanism was assumed. It was found that thesource of H^+ and the route of reaction initia... Up to now the mechanism of Priedel-Crafts reactions catalyzed by ionic liquidhave not been fully understood, while carbocation mechanism was assumed. It was found that thesource of H^+ and the route of reaction initiated the alkylation of benzene with ethylene catalyzedby [bmim]Cl/FeCl_3 ionic liquid. The fact that dewatered ionic liquids have catalytic activity forthe alkylation of benzene with ethylene suggests that there exists a new catalytic route. Thedistinctly Bronsted acid properties of 2-H in [bmim]Cl were found through FT-IR and HNMR analysis of[bmim]Cl after titration with water free KOH in alcohol solution. In addition, the chemical shiftsof proton on the [bmim]Cl ring, especially 2-H, are sensitive to the change of FeCl_3 content andshifted downfield when FeCl_3 was added into [bmim]Cl to form ionic liquid. Thus 2-H was easy to bedisengaged from imidazolium ring with formation of H^+ to initiate the reaction. Theisotope-substituted method was employed to prove this mechanism, through the GC-MS analysis ofalkylation products of deuterated benzene with ethylene. The route of alkylation catalyzed by FeCl_3ionic liquid was found to follow the carbocation mechanism, the resource of H^+ was presented andproved using HNMR analysis of ionic liquid to inspect the intensity change of 2-H. It was found thatthe intensity of 2-H reduced 23% after reaction showing that the H^+ arising from alkylationreaction was supplied by 2-H on the imidazole ring. 展开更多
关键词 ALKYLATION mechanism ETHYLENE BENZENE [bmim]Cl/FeCl_3 ionic liquid
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A pharmacodynamic model of portal hypertension in isolated perfused rat liver 被引量:2
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作者 Tao Zhang Xue-Yan Xu +7 位作者 Hang Zhou Xin Zhao Meng Song Tao-Tao Zhang He Yin Ting Li Peng-Tao Li Da-Yong Cai 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第5期472-478,共7页
AIM: To develop a pharmacodynamic model of porta hypertension from chronic hepatitis. METHODS: Pathological changes and collagen depositions were analyzed using morphometry to confirm CCI4-induced chronic hepatitis.... AIM: To develop a pharmacodynamic model of porta hypertension from chronic hepatitis. METHODS: Pathological changes and collagen depositions were analyzed using morphometry to confirm CCI4-induced chronic hepatitis. At do, d28, ds6 and d84 of the process, the portal perfused velocities (μL/min) in isolated rat livers were exactly controlled with a quanti-fied pump. The pressure (mmHg) was monitored with a Physiological System. The geometric concentrations of phenylephrine or acetylcholine were added to a fixed volume (300 mL) of the circulating perfusate. The equation, the median effective concentration and its 95% confidence intervals of phenylephrine or acetyl- choline were regressed with Prism-4 software in non-linear fit and various slopes. In the isolated perfused rat livers with chronic hepatitis, both median effective concentrations were defined as the pharmacodynamic model of portal hypertension.CONCLUSION: A pharmacodynamic model of portal hypertension in isolated perfused rat livers with chronic hepatitis was defined as the median effective concen- trations of phenylephrine and acetylcholine. 展开更多
关键词 Chronic hepatitis Isolated portal perfusedrat liver Pharmacodynamic model Portal hypertension
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Response of porcine hepatocytes in primary culture to plasma from severe viral hepatitis patients 被引量:6
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作者 Yong-Bo Cheng Ying-Jie Wang Shi-Chang Zhang Jun Liu Zhi Chen Jia-Jia Li 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第48期7585-7590,共6页
AIM: To observe the effects of plasma from patients with severe viral hepatitis (SVHP) on the growth and metabolism of porcine hepatocytes and the clinical efficiency of bioartificial liver device.METHODS: Hepatoc... AIM: To observe the effects of plasma from patients with severe viral hepatitis (SVHP) on the growth and metabolism of porcine hepatocytes and the clinical efficiency of bioartificial liver device.METHODS: Hepatocytes were isolated from male porcines by collagenase perfusion. The synthesis of DNA and total protein, leakages of AST and LDH, changes in glutathione (GSH), catalase and morphology of porcine hepatocytes exposed to SVHP were investigated to indicate the effect of plasma from patients with severe hepatitis on the growth, injury, detoxification, and morphology of porcine hepatocytes.RESULTS: The synthesis of DNA and protein was inhibited in the medium containing 100% SVHP compared to the controls. The leakages of LDH and AST increased in porcine hepatocytes following exposure to 100% SVHP for 5 h. The difference between 100% SVHP and 10% newborn calf serum (NCS) was significant in t-test (LDH: t = 24.552, P = 0.001; AST: t = 4.169, P = 0.014). After exposure to SVHP for 24 h, alterations in GSH status were significant (F = 2.746, P〈0.05) between porcine hepatocytes in 100% SVHP and 10% NCS, but no alteration occurred in the culture medium after 48 h (F = 4.378, ,P〈0.05). A similar profile was observed in catalase activity. Many round vacuoles were observed in porcine hepatocytes cultured in SVHR The membranes of these cells became indistinct and almost all the cells died on d 5.CONCLUSION: Plasma from patients with severe hepatitis inhibits the growth, injures membrane, disturbs GSH homeostasis and induces morphological changes of porcine hepatocytes, It is suggested that SVHP should be pretreated to reduce the toxin load and improve the performance of porcine hepatocytes in extracorporeal liver-support devices. 展开更多
关键词 Bioartificial liver Porcine hepatocytes CELLCULTURE Plasma toxicity
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