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Degradation of Hydrogenated Nitrile-butadiene Rubber in Aqueous Solutions of H2S or HCI

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Chemical Research in Chinese Universities 2013年第4期29卷 806-810页

作者： CONG Chuan-bo CUI Can-can MENG xiao-yu lu Shao-jie ZHOU Qiong Department of Material Science and Engineering Beijing Key Laboratory of Failure Corrosion and Protection of Oil~Gas Facilities China University of Petroleum(Beijing) Beijing 102249 P. R. China

The degradation of hydrogenated nitrile-butadiene rubber（HNBR） soaped in aqueous solutions of HzS and HC1 was investigated, The samples unexposed and exposed to different solutions were characterized by 13C nuclear magnetic resonance（~3C NMR）, X-ray photoelectron and infrared spectroscopies. In contrast to those of unexposed samples and samples soaped in HCI solution, the mechanical properties of samples exposed to H2S solution signifi- cantly deteriorated, in which the new groups of C（=O）--NH2, C--S--C and C=S emerged. The mechanism of C=S and C--S--C formation was speculated, except for that of the formation of group C（=O）--NH2, which was widely discussed in acidic condition such as HC1 solution. The formation of C--S--C was due to radical reaction in- itiated by mercapto radical and that of C=S was due to nucleophilic reaction initiated by mercapto cations. This finding is helpful to understanding the seal failure of HNBR in working cnvironment containing H2S.

关键词： Hydrogenated nitrile-butadiene rubbcr(HNBR) Degradation mechanism H2S corrosion

Potential geographical distribution of Rhagoletis pomonella （Diptera： Tephritidae）in China

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Insect Science 2011年第5期18卷 575-582页

作者： Jian Geng Zhi-Hong Li Edwin G. Rajotte Fang-Hao Wan xiao-yu lu Zhi-Ling Wang Department of Entomology College of Agronomy and Biotechnology China Agricultural University Beijing Gaoming Entry-Exit Inspection and Quarantine Bureau Foshan Guangdong Province China College of Agricultural Sciences The Pennsylvania State University State College Pennsylvania USA Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing Beijing Academy of Agriculture and Forestry Sciences Beijing China

Apple maggot fly, Rhagoletis pomonella （Walsh） is a major pest causing considerable economic losses of fruits in North America. During the development of international trade, apple maggot fly has become a threat to Chinese agriculture. In this study, CLIMEX and ArcGIS were used to predict the potential geographical distribution of apple maggot fly in China. The parameters used in CLIMEX for apple maggot fly were derived from ecological data and the present geographical distribution of apple maggot fly in North America. Then the potential distribution map in China was presented based on the adjusted values of these parameters. The results showed that apple maggot fly has a wide potential distribution area in China; 47.5% of 748 meteorological stations presented high or medium suitability of pest establishment. These high suitable stations are mainly located in northeast, southwest and northwest of China, such as Liaoning, Shandong, Gansu and Shaanxi Provinces. These areas are also the central regions of apple, pear and peach production in China. Two hundred and twenty-five stations （30.1%） in westem and southern China, such as Tibet, Qinghai, Guangdong, Guangxi, Hainan and Taiwan, were unsuitable for establishment of apple maggot fly populations. In order to prevent the introduction of apple maggot fly in China, the present plant quarantine measures should be enhanced, especially in the areas with high suitability for the presence of apple maggot fly.

关键词： apple maggot fly ArcGIS CLIMEX potential geographical distribution Rhagoletis pomonella (Walsh)

Iron-catalyzed decarboxylative and oxidative decarbonylative cross-coupling:a new strategy for the synthesis of monofluoroalkenes

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Organic Chemistry Frontiers 2022年第3期9卷 831-837页

作者： xiao-yu lu Meng-yuan Ge Ting-Hua Tao xiao-Mei Sun Meng-Ting Gao Shu-Ting Bao Qi-Le Liu Ze-Jie Xia Jing Xia School of Materials and Chemical Engineering ChuZhou UniversityChu Zhou239000China School of Chemistry and Chemical Engineering AnHui UniversityHe Fei230601China

Herein,an iron(II)-catalyzed decarboxylative and oxidative decarbonylative cross-coupling ofα-fluoro cinnamic acids with aliphatic aldehydes is *** methodology provided a novel and practical strategy for the construction of monofluoroalkenes from abundant and readily available aliphatic aldehydes,which are key functional groups in used in synthetic transformations in the pharmaceutical and agrochemical sciences.

关键词： oxidative carbonyl catalyzed

Heat transport properties within living biological tissues with temperature-dependent thermal properties

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Chinese Physics B 2023年第1期32卷 373-379页

作者：王颖泽陆晓宇刘栋 Department of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013China

Understanding of the heat transport within living biological tissues is crucial to effective heat treatments. The heat transport properties of living biological tissues with temperature-dependent properties are explored in this paper. Taking into account of variable physical properties, the governing equation of temperature is first derived in the context of the dualphase-lags model(DPL). An effective method, according to the Laplace transform and a linearization technique, is then employed to solve this nonlinear governing equation. The temperature distribution of a biological tissue exposed to a pulsed heat flux on its exterior boundary, which frequently happens in various heat treatments, is predicted and analyzed. The results state that a lower temperature can be predicted when temperature dependence is considered in the heating *** contributions of key thermal parameters are different and dependent on the ratio of phase lag and the amplitude of the exterior pulsed heat flux.

关键词： bio-heat transfer biological tissue temperature dependence analytical procedure

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Study on Emphases and Trend of Tianjin Urban Public Safety Planning from the View of Bohai Rim Megalopolis

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Journal of Civil Engineering and Architecture 2013年第10期7卷 1203-1208页

作者： Gong yuan xiao yu lu Li Tianjin Urban Planning and Design Institute Tianjin 300201 China

Nowadays urban public safety has been an important subject of study in urban planning study. And planners realized that a safe city is very important for sustainable development. Traditional urban public safety planning begins to perfect the contents and method. And regional research is an important aspect in the improvement of new era urban public safety planning. This paper chooses Tianjin, the important city in Bohai rim area as the example for research. Tianjin urban public safety planning includes not only comprehensive disaster prevention and reduction, effectively preventing and reducing disasters, ensuring the safety of the life and property of the residents, but also sharing resources and facilities from the view of megalopolis, eliminating hidden area troubles, reducing whole environment risks and so on.

关键词： Urban public safety planning Tianjin Bohai rim megalopolis emphases.

Determination of Shallow Impurity Concentration in Detector-grade Silicon by FT-IR Spectroscopy at 4.2K

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Rare Metals 1989年第4期9卷 54-58页

作者： Zhang, Jichang Wu, Jiangen Qu, Fengyuan Ye, Hongjuan xiao, Jincai yu, Zhiyi lu, Wei Tongji Univ China

A Nicolet-200SXV FT-IR spectrometer combined with an exciting light set-up has been applied to determine the shallow impurity concentration in detector-grade silicon. The detection sensitivity of boron concentration is high up to 7.8 × 10-12. The calibration curve of boron concentration in high-purity silicon has been obtained, from which the experimental value of calibration factor of boron concentration in silicon is demonstrated to be 1.15 × 1013 cm-1.

关键词： Boron Trace Analysis Radiation Detectors Silicon Spectrometers, Infrared Sensitivity Spectroscopy, Infrared Low Temperature

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Agglutinin isolated from Arisema heterophyllum Blume induces apoptosis and autophagy in A549 cells through inhibiting PI3K/Akt pathway and inducing ER stress

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Chinese Journal of Natural Medicines 2016年第11期14卷 856-864页

作者： FENG Li-Xing SUN Peng MI Tian LIU Miao LIU Wang YAO Si CAO Yi-Min yu xiao-lu WU Wan-Ying JIANG Bao-Hong YANG Min GUO De-An LIU Xuan Shanghai Institute of Materia Medica Chinese Academy of Sciences

Arisaema heterophyllum Blume is one of the three medicinal plants known as traditional Chinese medicine Rhizoma Arisaematis(RA). RA has been popularly used to treat patients with convulsions, inflammation, and cancer for a long time. However, the underlying mechanisms for RA effects are still unclear. The present study was designed to determine the cytotoxicity of agglutinin isolated from Arisema heterophyllum Blume(AHA) and explore the possible mechanisms in human non-small-cell lung cancer A549 cells. AHA with purity up to 95% was isolated and purified from Arisaema heterophyllum Blume using hydrophobic interaction chromatography. AHA dose-dependently inhibited the proliferation of A549 cells and induced G_1 phase cell cycle arrest. AHA induced apoptosis by up-regulating pro-apoptotic Bax, decreasing anti-apoptotic Bcl-2, and activating caspase-9 and caspase-3. In A549 cells treated with AHA, the PI3K/Akt pathway was inhibited. Furthermore, AHA induced increase in the levels of ER stress markers such as phosphorylated eukaryotic initiation factor 2α(p-eIF2α), C/EBP-homologous protein(CHOP), inositol-requiring enzyme 1α(IRE1α), and phosphorylated c-Jun NH_2-terminal kinase(p-JNK). AHA also induced autophagy in A549 cells. Staining of acidic vesicular organelles(AVOs) and increase in the levels of LC3II and ATG7 were observed in AHA-treated cells. These findings suggested that AHA might be one of the active components with anti-cancer effects in Arisaema heterophyllum Blume. In conclusion, cytotoxicity of AHA on cancer cells might be related to its effects on apoptosis and autophagy through inhibition of PI3K/Akt pathway and induction of ER stress.

关键词： Agglutinin Arisaema heterophyllum Blume Human non-small-cell lung cancer A549 cell line Apoptosis Autophagy

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Histamine ameliorates spatial memory deficits induced by MK-801 infusion into ventral hippocampus as evaluated by radial maze task in rats

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Acta Pharmacologica Sinica 2005年第12期26卷 1448-1453页

作者： Li-sha XU Li-xia YANG Wei-wei HU xiao yu Li MA lu-ying LIU Er-qing WEI Zhong CHEN~2 Department of Pharmacology School of Medicine,Zhejiang University,Hangzhou 310031,China Department of Pharmacology School of Medicine Zhejiang University Hangzhou China

Aim:To investigate the role of histamine in memory deficits induced by MK-801infusion into the ventral hippocampus in ***:An 8-arm radial maze(4arms baited)was used to assess spatial ***:Bilateral ventralintrahippocampal(ih)infusion of MK-801(0.3 μg/site),an N-methyl-D-aspartate(NMDA)antagonist,impaired the retrieval process in both working memory andreference *** injection of histamine(25 or 50 ng/site)orintraperitoneal(ip)injection of histidine(25,50 or 100 mg/kg)markedly amelio-rated the spatial memory deficits induced by *** the histamine H1an-tagonist pyrilamine(0.5 or 1.0 μg/site,ih)and the H2 antagonist cimetidine(2.5 μg/site,ih)abolished the ameliorating effect of histidine( 100 mg/kg,ip)on reference memorydeficits,but not that on working memory deficits induced by ***:The results indicate that histamine in the ventral hippocampus can ameliorateMK-801-induced spatial memory deficits,and that histamine’s effect on referencememory is mediated by postsynaptic histamine H1and H2receptors.

关键词： histamine: maze learning MK-801 working memory reference memory ventral hippocampus histamine H1 receptor

De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

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Science China Chemistry 2025年第1期68卷 174-180页

作者： Fan-xiao Meng Xing-yu Wang Ka lu Ju-Song Yang Fu-Min Zhang Ai-Jun Ma Bao Du Yong-Qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

关键词： benzofuran atropisomers novel de novo synthetic strategy asymmetric formal [3 + 2] cycladdition Cu/SPDO complex DFT calculations