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Synthesis of 5-vinyl-2-norbornene through Diels-Alder reaction of cyclopentadiene with 1,3-butadiene in supercritical carbon dioxide

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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

Condition-based Maintenance Optimization for Gamma Deteriorating Systems under Performance-based Contracting

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 34-50页

作者： Xi zhu Liang Wen juan Li Mingchang Song Qiwei Hu Army Engineering University of PLA ShijiazhuangChina

With the further development of service-oriented,performance-based contracting(PBC)has been widely adopted in industry and ***,maintenance optimization problems under PBC have not received enough *** further extend the scope of PBC’s application in the field of maintenance optimization,we investigate the condition-based maintenance(CBM)optimization for gamma deteriorating systems under *** the repairable single-component system subject to the gamma degradation process,this paper proposes a CBM optimization model to maximize the profit and improve system performance at a relatively low cost under *** the proposed CBM model,the first inspection interval has been considered in order to reduce the inspection frequency and the cost ***,a particle swarm algorithm(PSO)and related solution procedure are presented to solve the multiple decision variables in our proposed *** the end,a numerical example is provided so as to demonstrate the superiority of the presented *** comparing the proposed policy with the conventional ones,the superiority of our proposed policy is proved,which can bring more profits to providers and improve *** analysis is conducted in order to research the effect of corrective maintenance cost and time required for corrective maintenance on optimization policy.A comparative study is given to illustrate the necessity of distinguishing the first inspection interval or not.

关键词： Performance-based contracting Condition-based maintenance Gamma process Profit maximization Inspection interval

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

Chemical composition and larvicidal effects of essential oil of Blumea martiniana against Anopheles anthropophagus

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Asian Pacific Journal of Tropical Medicine 2011年第5期4卷 371-374页

作者： Liang zhu Ying-juan Tian College of Food and Bioengineering South China University of TechnologyGuangzhouGuangdong ProvinceChina

Objective:To determine chemical composition of the hydrodistilled essential oil of Blumea martiniana,and to evaluate its larvicidal activity against Anopheles anthropophagus,the natural vector of ***:Chemical composition of essential oils extracted by steam distillation was investigated by gas chromatography and mass spectroscopy（GC-MS）.Larvicidal activity of essential oil and its four main compounds was carried out by WHO *** larvae of early fourth-instar stage were used in the larvicidal assay and five replicates were maintained for each *** 24 h LC50 and LC90 values were determined following probit ***:Totally 68 compounds corresponding to 98.55%of the total oil were identified and the major constituents of essential oil were:linalool（10.36%）,germacrene D（9.09%）, borneol（6.24%）,γ-terpinene（5.38%）.The oil and linalool,germacrene D,bomeol,γ-terpinene exerted significant larvicidal activity with LC50 values of 46.86,35.87,44.61,35.89,and 29.21 mg/L, *** also showed a dose dependent effect on ***:The essential oil of Blumea martiniana and its four major compounds may have potential for use in control of Anopheles anthropophagus larvae and could be useful in search of newer,safer and more effective natural compounds as larvicides.

关键词： Blumea martiniana Essential oil Composition Larvicidal Anopheles anthropophagus

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.

Preparation and Investigation of Arsenic Trioxide-loaded Polylactic Acid/Magnetic Hybrid Nanoparticles

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Chemical Research in Chinese Universities 2014年第2期30卷 326-332页

作者： SONG Xiaoli YOU juan WANG juan zhu Aiping JI Lijun GUO Rong College of Chemistry and Chemical Engineering Yangzhou University Yangzhou 225002 P.R.China

In order to improve the therapeutic index and reduce the side effects of As2O3 so as to expand its clinical utility to solid tumors,As2O3-loaded polylactic acid（PLA）/magnetic nanoparticles（PAMNs） were prepared and the preparation conditions were optimized by the improved double emulsion solvent-evaporation method to obtain as a drug delivery system with a high As2O3 encapsulation efficiency and homogeneous nanosized *** loading of magnetic nanoparticles into the nanoparticles was confirmed by Fourier transform infrared（FTIR） *** drug loading,encapsulation efficiency and releasing properties of As2O3 in PAMNs were investigated by atomic fluorescence spectrometer ***,the in vitro antitumor efficacy of free As2O3 and As2O3-PAMNs against SMMC-7721 cell line was ***,confocal fluorescence microscopy was conducted to reveal the celluar uptake of As2O3-loaded PAMNs by SMMC-7721 cell line.

关键词： As2O3 Magnetism Polylactic acid nanoparticle Drug release