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Chinese Chemical Letters 2017年第4期28卷 900-904页

作者： Fan-Qiang Meng xiu-juan Feng Wan-Hui Wang Ming Bao State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116023 China School of Petroleum and Chemical Engineering Dalian University of Technology Panjin 124221 China

An efficient method for the synthesis of 5-vinyl-2-norbornene from cyclopentadiene and 1,3-butadiene was *** Diels-Alder reaction of cyclopentadiene with 1,3-butadiene proceeded smoothly in supercritical carbon dioxide in the absence of any polymerization inhibitor to produce the corresponding5-vinyl-2-norbornene in satisfactory yield with high selectivity.

关键词： 5-Vinyl-2-norbornene Diels-Alder reaction Cyclopentadiene 1 3-Butadiene Supercritical carbon dioxide

Automatic ^(40)Ar/^(39)Ar Dating Techniques Using Multicollector ARGUS VI Noble Gas Mass Spectrometer with Self-Made Peripheral Apparatus

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Journal of Earth Science 2018年第2期29卷 408-415页

作者： xiu-juan Bai Hua-Ning Qiu Wen-Gui Liu Lian-Fu Mei Key Laboratory of Tectonics and Petroleum Resources Ministry of Education China University of Geosciences State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

A new fully automatic ^40Ar/^39Ar laboratory with a Thermo Scientific ARGUS VI mass spectrometer has been established in China University of Geosciences （Wuhan）. We designed and developed a mini efficient preparation system （80 mL）, a CO2 laser for heating samples, a crusher for extracting fluid inclusions within K-poor minerals and an air reservoir （31 L） and pipette （0.1 mL） system. The ARGUS VI mass spectrometer is operated by the Qtegra Noble Gas software, which can control the peripheral accessories, such as pneumatic valves, CO2 laser and crusher through a PeriCon （peripheral controller）. The experimental procedures of atmospheric argon ana- lyses, ^40Ar/^39Ar dating by laser stepwise heating and by progressive crushing in vacuo, can be fully automatically performed. The weighted mean of atmospheric ^40Ar/^36Ar ratios is 302.22＋0.03 （1σ, MSWD=0.74, n=200）, indicating that air reservoir and pipette system and the whole instrument sys- tem are very stable. This laboratory is a successful pioneer example in China to establish a new no- ble gas laboratory with self-made peripheral accessories expect for the mass spectrometer.

关键词： ^40Ar/^39Ar dating fully automatic CO2 laser ARGUS VI mass spectrometer Qtegra noble gas software.

Influence of γ-ray Irradiation on the PTC Effect of EPDM/Carbon Black Composite

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Chemical Research in Chinese Universities 2000年第3期16卷 283-285页

作者： HE xiu juan WANG Li jie CHEN Xin fang Institute of Materials Science Jilin UniversityChangchun 130023China

The positive temperature coefficient (PTC) effect is characterized by an increase of resistivity with an elevated temperature. The PTC effect of carbon black (CB) filled polymers is useful for self-regulation heaters, over-current protectors and sensors. The influence of γ-ray irradiation on the PTC effect of CB filled amorphous ethylene-propylene-diene terpolymer (EPDM) composites is studied.

关键词： Conducting composite PTC effect EPDM Carbon black

Sodium valproate suppresses abnormal neurogenesis induced by convulsive status epilepticus

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Neural Regeneration Research 2019年第3期14卷 480-484页

作者： Peng Wu Yue Hu xiu-juan Li Min Cheng Li Jiang Department of Neurology Children's Hospital of Chongqing Medical University Chongqing International Science and Technology Cooperation Center for Child Development and Disorders Ministry of Education Key Laboratory of Child Development and Disorders Key Laboratory of Pediatrics in Chongqing

Status epilepticus has been shown to activate the proliferation of neural stem cells in the hippocampus of the brain, while also causing a large amount of neuronal death, especially in the subgranular zone of the dentate gyrus and the subventricular zone. Simultaneously, proliferating stem cells tend to migrate to areas with obvious damage. Our previous studies have clearly confirmed the effect of sodium valproate on cognitive function in rats with convulsive status epilepticus. However, whether neurogenesis can play a role in the antiepileptic effect of sodium valproate remains unknown. A model of convulsive status epilepticus was established in Wistar rats by intraperitoneal injection of 3 mEq/kg lithium chloride, and intraperitoneal injection of pilocarpine 40 mg/kg after 18–20 hours. Sodium valproate(100, 200, 300, 400, 500, or 600 mg/kg) was intragastrically administered six times every day(4-hour intervals) for 5 days. To determine the best dosage, sodium valproate concentration was measured from the plasma. The effective concentration of sodium valproate in the plasma of the rats that received the 300-mg/kg intervention was 82.26 ± 11.23 μg/mL. Thus, 300 mg/kg was subsequently used as the intervention concentration of sodium valproate. The following changes were seen: Recording excitatory postsynaptic potentials in the CA1 region revealed high-frequency stimulation-induced long-term potentiation. Immunohistochemical staining for BrdU-positive cells in the brain revealed that sodium valproate intervention markedly increased the success rate and the duration of induced long-term potentiation in rats with convulsive status epilepticus. The intervention also reduced the number of newborn neurons in the subgranular area of the hippocampus and subventricular zone and inhibited the migration of newborn neurons to the dentate gyrus. These results indicate that sodium valproate can effectively inhibit the abnormal proliferation and migration of neural stem cells and n

关键词： nerve regeneration status epilepticus sodium valproate long-term potentiation neural stem cells neurogenesis migration subgranular zone subventricular zone neural regeneration

Influence of slip ratio on worn-surface microstructure and fatigue wear behavior of D2 wheel steel

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Journal of Iron and Steel Research International 2018年第12期25卷 1278-1286页

作者： Chun-peng Liu xiu-juan Zhao Peng-tao Liu Chong Xu Rui-ming Ren School of Material Science and Engineering Dalian Jiaotong UniversityDalian 116028LiaoningChina Key Laboratory of Critical Materials of Rail Transportation in Liaoning Province Dalian Jiaotong University Dalian 116028LiaoningChina School of Mechanical Engineering Dalian Jiaotong UniversityDalian 116028LiaoningChina

To investigate the worn-surface microstructure and fatigue cracks in D2 wheel steel under the pure rolling and 0.5% slip ratio conditions,a rolling wear test using a GPM-40 wear machine to simulate the wheel/rail operation was performed. After testing,a transmission electron microscope,a scanning electron microscope with electron backscatter diffraction,and micro-hardness testers were used to characterize the microstructure and fatigue *** surface microstrncture and hardness of the pure rolling sample were in a steady state after 8 × 10^4 cycles;however,the 0.5% slip ratio sample reached a steady state after 7 × 10^3 *** of whether the test uses the slip ratio,the orientation of lamellar pearlites gradually became parallel to the surface and a portion of lamellar cementites was fragmented and dissolved during the formation of steady-state *** slip ratio accelerates this *** hardening mechanism of the samples shows a decrease in the lamellar spacing of pearlite and the refinement of proeutectoid ferrite (PF).As the number of cycles increased,plastic deformation of samples became increasingly severe and the wear mechanism of the samples was fatigue wear in steady *** sample surfaces formed shallow cracks,which gradually peeled *** slip ratio accelerated the initiation and propagation of fatigue cracks because of the high friction stress on the contact *** fatigue cracks initiated at the interface of pearlite and PF and in the PF region.

关键词： D2 wheel steel Slip ratio Wom-surface microstructure Wheel/rail system Rolling wear

Effect of shenfu injection on gastrointestinal microcirculation in rabbits after myocardial ischemia-reperfusion injury

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World Journal of Gastroenterology 2006年第27期12卷 4389-4391页

作者： Xue-juan Zhang Li Song Zan-Gong Zhou xiu-Mei Wang Department of Cardiology Affiliated Hospital of Qingdao Medical University Qingdao 266003 Shandong Province China

AIM： To investigate the effect of shenfu injection on gastrointestinal microcirculation after myocardial ischemic-reperfusion （IR） injury in rabbits and probe into the mechanism. METHODS： Forty healthy flap-eared white rabbits were randomly divided into 4 groups： IR injury control group （group Ⅰ ）, shenfu injection 5 mL/kg per h group （group Ⅱ）, shenfu injection 10 mL/kg per h group （group Ⅲ） and shenfu injection 20 mL/kg per h group （group Ⅳ）. The four groups were treated with Lactated Ringer＇s solution, shenfu injection 5, 10, and 20 mL/ kg per h were infused intravenously 30 min before experiment respectively. The values of hemodynamics [mean arterial pressure （MAP）, heart rate （HR）, gastric intramucosal partial pressure of carbon dioxide （PCO2）, blood gas analysis and pH] were measured and compared with those before myocardial ischemia, 60 min after myocardial ischemia and 60, 90, and 180 rain after reperfusion. RESULTS： The MAP, HR and gastric intramucosal pH were （70.50 ± 4.50） kPa, （165 ± 14） beats per rain, 7.032 ± 0.024 in group Ⅰ 60 min after myocardial ischemia, which were significantly decreased compared with those before myocardial ischemia （88.50 ± 9.75 kPa, 217 ± 18 beats per rain, 7.112 ± 0.035, P 〈 0.05）. The MAP, HR and gastric intramucosal pH were significantly decreased in group Ⅰ 60, 90, and 180 min after reperfusion （61.50 ± 5.25 kPa, 133 ± 31 beats per rain, 6.997 ± 0.025） compared with those before reperfusion respectively （P 〈 0.05）, whereas the values were insignificantly different in groups Ⅱ, Ⅲ or Ⅳ after reperfusion, compared with those before reperfusion, and there were no significant differences between groups Ⅱ, Ⅲ, and Ⅳ after reperfusion. CONCLUSION： Pre-infusion of shenfu injection has a protective effect on gastrointestinal microcirculation after myocardial IR injury in rabbits, in a dose independent manner.

关键词： Shenfu injection Myocardial ischemicreperfusion injury Gastrointestinal microcirculation

Construction and Characterization of a cDNA Library from the Pulp of Cara Cara Navel Orange （Citrus sinensis Osbeck）

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Journal of Integrative Plant Biology 2006年第3期48卷 315-319页

作者： Neng-Guo Tao juan Xu Yun-Jiang Cheng xiu-Xin Deng State Key Laboratory of Crop Genetic Improvement National Center of Citrus Breeding Huazhong Agricultural University Wuhan 430070 China

A cDNA library was constructed end characterized from the pulp of Cera Care navel orange （Citrus sinensis Osbeck） at different stages of ripening. Tittering results revealed that approximately 5.086×10^5 independent clones were included in this library. Electrophoresls gel results of 15 randomly selected clones revealed that the size of the insertion fragments ranged from 400 bp to 2 kb, with an average size of 900 bp. Sequencing results of 150 randomly picked clones showed that the recombination rate was 94%. During subsequent sequence analysis, 41 of 139 clones failed to be identified end the amino sequence of 71 clones shared less than 30% identity with related plants in GenBank. Of 27 clones whose amino sequences shared more than 60% identity with other related plants in GenBenk, 17 clones showed an 80% identity with the corresponding candidate genes of citrus. The clone recognized as the type Ⅲ metallothlonein-llke （MT） gene was observed to occur 13 tlmes, Indlcatlng that the protein may play an important role In frult development and rlpenlng.

关键词： Cara Cara navel orange cDNA library Citrus, pulp.

Ca_(0.5)Sr_(0.5)TiO_(3)-Modified KNN-Based Lead-Free Piezoceramics with a Wide Temperature Usage Span

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Chinese Physics Letters 2011年第6期28卷 280-282页

作者： DU juan WANG Jin-Feng ZANG Guo-Zhong YI xiu-Jie College of Materials Science and Engineering Liaocheng UniversityLiaocheng 252059 School of Physics Shandong UniversityJi'nan 250100

The strong temperature dependence of dielectric and piezoelectric properties is a big'bottleneck'for practical applications of KNN-based *** order to resolve this problem,Ca_(0.5)Sr_(0.5)TiO_(3)(CST)is doped into(Na_(0.53)K_(0.4)0_(7)Li_(0.063))Nb0.937Sb0.063O3(NKLNS)*** thermal stability of s11E and k31 in the temperature range from−50℃to 200℃for ceramics with 1.0 and 1.5 mol%CST is raised in comparison with ceramics without *** with 1.5 mol%CST exhibit high piezoelectric properties(d33=202 pC/N,kp=44%)and low dielectric loss(2%)at room *** excellent piezoelectric properties,which are comparable to conventional PZT ceramics,indicate that these ceramics are promising candidates for lead-free piezoelectric applications.

关键词： ceramics temperature piezoelectric

Preparation and Catalytic Application of Novel Water Tolerant Solid Acid Catalysts of Zirconium Sulfate/HZSM-5

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Chemical Research in Chinese Universities 2007年第3期23卷 349-354页

作者： JIANG Ya-jie juan Joon Ching MENG xiu-juan CAO Wei-liang YARMO Mohd Ambar ZHANG Jing-chang State Key Laboratory of Chemical Resource Engineering Ministry of Education Institute of Modern Catalysis Beijing University of Chemical Technology Beijing 100029 P. R. China Advanced Catalysis Technology Laboratory School of Chemical Sciences and Food Technology Faculty of Science and Technology Universiti Kebangsaan Malaysia Bangi 43600 Malaysia

Esterification of acrylic acid（AA） to produce AA esters has widespread application in the chemical industry. A series of water tolerant solid acid catalysts was prepared, and characterized by XRD, nitrogen adsorption, TGA-DTA, XPS, and ammonia adsorption FTIR. The effects of Si/Al ratio, zirconium sulfate（ZS） loading on HZSM-5 and calcination temperature on the esterification were investigated. When 20% （mass fraction） ZS is loaded on HZSM-5, the conversion of AA reaches 100%. XRD analysis indicates that ZS is highly dispersed on HZSM-5 because no crystalline structure assigned to ZS is found. Catalytic activity and hydrophobicity of ZS supported on HZSM-5 are higher compared with those of parent ZS or HZSM-5. Results show that this kind of novel catalysts is an efficient water tolerant solid acid catalyst for esterification reactions.

关键词： Solid acid catalyst Zirconium sulfate HZSM-5 Esterification reaction Water tolerant

Experimental study on a -60 °C cascade refrigerator with dual running mode

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第5期13卷 375-381页

作者： xiu-fang LIU Jiong-hui LIU Hong-li ZHAO Qiao-yu ZHANG juan-li MA Institute of Refrigeration and Cryogenic Engineering Xi'an Jiaotong University Xi 'an 710049 China School of Mechanical and Power Engineering Henan Polytechnic University Jiaozuo 454000 China

In this study,an experimental setup is designed and built to investigate the feasibility and performance of the proposed dual-mode cascade refrigeration *** apparatus can be operated in two modes:dual-stage mode and single-stage mode such that the low temperature cycle(LTC) can be operated together with the high temperature cycle(HTC) or can run *** results validate the feasibility of independent operation of *** performance of the independent operation of LTC mode is theoretically investigated using experimental data as *** suggestions are made for the improvement of the coefficient of performance(COP) of the experimental ***,high COP of the cycle provides excellent application for the presented refrigeration cycle.

关键词： Cascade refrigeration Dual-mode Regenerator Optimization Effectiveness