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Chinese Journal of Chemistry 2020年第11期38卷 1252-1256页

作者： Mengyao zhang Yingying zhang huixin zhang Yongfei Zeng Guiyan Liu Tianjin Key Laboratory of Structure and Performance for Functional Molecules Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry(Tianjin Normal University)Ministry of EducationCollege of ChemistryTianjin Normal UniversityTianjin 300387China

of main observation and conclusion A highly efficient catalytic system for the N-arylation reactions of(hetero)aryl chlorides and nitrogen heterocycles with a copper(l)complex containing a 1,10-phenanthroline analogue N-heterocyclic carbene(NHC)has been *** complex was characterized by^lH NMR and^13C NMR spectroscopy and elemental analysis,and its structure was determined by single-crystal X-ray *** NHC-copper(l)complex was employed as pre-catalyst for Ullmann type N-arylation reactions of(hetero)aryl chlorides with various azoles.A variety of hindered and functionalized azoles and(hetero)aryl chlorides were transformed in good to excellent yields.

关键词： diffraction. copper Catalytic

Ionic liquid modified Pt/C electrocatalysts for cathode application in proton exchange membrane fuel cells

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Frontiers of Chemical Science and Engineering 2019年第4期13卷 695-701页

作者： huixin zhang Jinying Liang Bangwang Xia Yang Li Shangfeng Du School of Chemical Engineering University of Birmingham.Birmingham B152TTUK School of Chemical Engineering Hebei University of TechnologyTianjin 300130China

The modification of Pt/C catalyst by using ionic liquids to improve their catalyst activities has been reported by many researchers,but their practical behavior in operating fuel cells is still *** this work,we study the ionic liquid modified Pt/C nanoparticle catalysts within cathodes for proton exchange membrane fuel *** influence of the ionic liquid amount,adsorption times and dispersing solvents are *** experiment results show the best performance enhancement is achieved through two-time surface modification with 2 wt-%ionic liquid *** mechanisms are explored with the attribution to the high oxygen solubility in the ionic liquid enabling an improved oxygen diffusion in micropores and to good hydrophobicity facilitating water expelling from the active sites in fuel cell operation.

关键词： ionic liquid PEMFC electrode oxygen reduction reaction electrocatalyst adsorption

Highly Active Pd-PEPPSI Complexes for Suzuki-Miyaura Cross-coupling of Aryl Chlorides:an Investigation on the Effect of Electronic Properties

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Chemical Research in Chinese Universities 2020年第5期36卷 859-864页

作者： zhang Yingying HAN Fangwai zhang Mengvao zhang huixin LI Ying WANG Ru ZENG Yongfei LIU Guiyan Tianjin Key Laboratory of Stmcture and Performance for Functional Molecules Key Laboratory of Inorganic-organic Hybrid Functional Material ChemistryMinistry of EducationCollege of ChemistryTianjin Normal UniversityTianjin 300387P.R.China

Three new Pd-pyridine enlianced precatalyst preparation stabilization and initiation(PEPPSI)complexes with halogen groups on the N-heterocyclic carbene and pyridine were *** structures have been clearly characterized by nuclear magnetic resonance spectroscopy and X-ray single-crystal di *** e fleets of the electronic properties of halogen groups on the catalytic activity in the Suzuki-Miyaura cross-coupling of aryl chlo-rides were *** Pd-PEPPSI complexes could catalyze the cross-coupling reaction efficiently with a low catalyst loading(0.05%,molar ratio)at room temperature and the products were obtained in high yields.

关键词： Pd-pyridine enhanced precatalyst preparation stabilization and initiation(PEPPSI)complex Suzuki-Miyaura cross-coupling reaction Aryl chloride

Effect of nitric oxide synthase inhibitor N^G-nitro-L-arginine on the content of amino acid in ischemic brain tissues of rats

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Neural Regeneration Research 2006年第4期1卷 309-312页

作者： Jianxin zhang huixin zhang Lanfang Li Qinzeng zhang Yonghui Li Department of Pharmacology Hebei Academy of Medical Sciences Shijiazhuang 050021Hebei Province China

BACKGROUND： Nitric oxide synthase （NOS） inhibrtors have been widely used to investigate the role of NO on cerebral ischemic injury, but the results are controversial. Moreover, it has been considered to aggravate the ischemic neuronal damage with the release of excessively excitatory amino acids （EAA） during cerebral ischemia. On the other hand, some inhibitory amino acid is suggested to be important for the neuronal protection against ischemic brain damage. Our study has recently showed that treatment with the NOS inhibitor NG-nitro-L-arginine （L-NA） reduced focal cerebral ischemic damage. The effect of L-NA on the contents of excitatory and inhibitory amino acid in the rat brain following cerebral ischemia is still unclear. OBJECTIVE： By evaluating the effect of NOS inhibitor, L-NA on the contents of aspartate, glutamate, glycine and γ-aminobutyric acid （GABA） in striatum, hippocampus and cortex in the rat brain following cerebral ischemia respectively, to investigate the beneficial effect of L-NA on cerebral ischemic injury and the possible mechanism. DESIGN： A randomized and controlled experiment SETTING ： Department of Pharmacology, Hebei Academy of Medical Sciences MATERIALS： A total of 42 male healthy SD rats （grade Ⅱ, weighting 250-300 g） were provided by the Experimental Animal Center of Hebei Province （Certification： 04036）. Aspartate, glutamate, glycine, GABA, L-NA and 2,3,5-triphenyltetrazolium chloride （TTC） were obtained from Sigma Chemicals Co, St Louis, MO, USA. HPLC-ultraviolet detector system consisted of Agilent 1100 HPLC. METHODS： The experiment was carried out in Department of Pharmrcology, Hebei Academy of Medical Sciences from June 2005 to June 2006. Rats were randomly divided into three groups： sham-operated group （n = 6）, ischemic group （n = 18）, L-NA group （n = 18）. The model of focal cerebral ischemia in rat was prepared with intraluminal line occlusion methods. In sham-operated rats, the external carotid artery was surgically pr

关键词： acid Effect of nitric oxide synthase inhibitor N^G-nitro-L-arginine on the content of amino acid in ischemic brain tissues of rats

Data driven reduced modeling for fluidized bed with immersed tubes based on PCA and Bi-LSTM neural networksAuthor links open overlay panel

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Particuology 2024年第8期91卷 1-18页

作者： Jiabin Fang Wenkai Cu Huang Liu huixin zhang Hanqing Liu Jinjia Wei Xiang Ma Nan Zheng School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'anShaanxi 710049China

The fast and accurate reduced-order modeling of fluidized beds is a challenging task in the field of fluid dynamics,owing to their high dimensionality and nonlinear dynamic *** this study,a nonintrusive reduced order modeling method,the reduced order model based on principal component analysis and bidirectional long short-term memory networks(PBLSTM ROM),was developed to capture complex spatio-temporal dynamics of fluidized *** combining principal component analysis and Bidirectional long-short-term memory networks,the PBLSTM ROM effectively extracted dynamic evolution information without any prior knowledge of governing equations,enabling reduced-order modeling of unsteady flow *** PBLSTM ROM was validated using the solid volume fraction and gas velocity flow fields of a fluidized bed with immersed tubes,showing superior performance over both the PLSTM and PANN ROMs in accurately capturing temporal changes in the fluidization fields,especially in the region near immersed tubes where severe fluctuations ***,the PBLSTM ROM improved the simulation speed by five orders of magnitude compared to traditional computational fluid dynamics *** findings suggest that the PBLSTM ROM presents a promising approach for analyzing the complex fluid flows in engineering practice.

关键词： Reduced order modeling Fluidized bed Deep learning Bi-LSTM

Effects of NG-nitro-L-arginine on focal cerebral ischemic injury in rats

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Neural Regeneration Research 2006年第1期1卷 40-43页

作者： Jianxin zhang huixin zhang Lanfang Li Yonghui Li Department of Pharmacology Academy of Medical Science of Hebei Province Shijiazhuang 050021 Hebei Province China

BACKGROUND： Previous researches have proved that aminoguanidin can cure cerebral ischemic injury remarkably as a selective induced nitricoxide synthase （iNOS） inhibitor. However, whether nonselective NOS inhibitor could protect cerebral ischemic injury or not is unclear. OBJECTIVE： To investigate the effects of NG-nitro-L-arginine （L-NA）, a nonselective nitricoxide synthase （NOS） inhibitor, on cerebral ischemic injury of rats and the possible mechanism.DESIGN： Randomized controlled study.SETTING ： Pharmacological Department of Medical Academy of Science of Hebei Province.MATERIALS： A total of 56 male healthy SD rats, of grade Ⅱ, weighting 250-290 g, were provided by the Experimental Animal Center of Hebei Province （certification： 04036）. METHODS： The experiment was completed in the Pharmacological Department of Medical Academy of Science of Hebei Province from March 2005 to January 2006.① Grouping： Rats were randomly divided into 3 groups： sham operation group （n=8）, model group （n=24） and L-NA group （n=24）.② Modeling： Middle cerebral artery （MCA） was established on rats in model group and L-NA group with intreluminal line occlusion methods, and rats in sham operation group were separated their external carotid arteries without occlusion of internal carotid artery. ③ Intervention study： Rats in model group and L-NA group were injected intreperitoneally with 10 mL/kg and 20 mg/kg L-NA at 2, 6 and 12 hours respectively after ischemia twice a day for 3 consecutive days. ④ Rats were sacrificed on the third day for measuring volume of cerebral infarction with image analysis and swelling degrees and activities of mitochondria with electron microscope. Effect of L-NA on ultrastructural changes of neurons in cortex was observed after ischemia. MAIN OUTCOME MEASURES：① Volume of cerebral infarction; ②Swelling degrees, contents of nitric oxide （NO） and malondialdehyde （MDA） and activities of adenosine triphosphatase （ATPase）, superoxide dismutase （SOD） and glutathi

关键词： Effects of NG-nitro-L-arginine on focal cerebral ischemic injury in rats NG

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外泌体生物分析及其临床应用研究进展

高等学校化学学报 2020年第11期41卷 2306-2323页

作者：张怡萌张慧欣刘洋清华大学化学系微量分析测试方法与仪器研制北京市重点实验室生物有机磷化学及化学生物学教育部重点实验室北京100084 青岛大学化学化工学院山东省中日碳纳米材料合作研究中心青岛266071

外泌体是具有各种关键生物活性分子(如脂质、蛋白质和核酸)的细胞外囊泡.它们可以由所有类型的细胞分泌,并分布在所有生物流体中,如血液、唾液、汗水和尿液等.更重要的是,外泌体可以参与多种生理活动,包括细胞间通讯、哺乳动物的繁殖和... 详细信息

外泌体是具有各种关键生物活性分子(如脂质、蛋白质和核酸)的细胞外囊泡.它们可以由所有类型的细胞分泌,并分布在所有生物流体中,如血液、唾液、汗水和尿液等.更重要的是,外泌体可以参与多种生理活动,包括细胞间通讯、哺乳动物的繁殖和免疫反应,并在新陈代谢以及心血管疾病、神经变性和癌症等疾病的病理进展中起重要作用,这使其成为备受关注的天然非侵入性生物标记物,并且被认为是可用于临床诊断和治疗的潜在工具。本文综述了用于检测外泌体的生物传感器的最新发展,包括荧光、电化学、电化学发光、表面增强拉曼光谱、比色法和微流控技术等分析方法;总结了在临床诊断和疾病治疗中外泌体的临床应用;还讨论了外泌体检测所面临的挑战以及外泌体在临床诊断和疾病治疗等方面的应用潜力.

关键词：外泌体生物传感器定量分析临床应用

Trace glucose fluxes in individuals with prediabetes using stable isotopes

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Chinese Medical Journal 2014年第9期127卷 1726-1731页

作者： Du Shichun Xia Fangzhen Xu Xiao zhang huixin Zhu Chunfang Lu Yingli Institute and Department of Endocrinology and Metabolism Shanghai Ninth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200011 China

Background The glucose fluxes of individuals with prediabetes in Chinese population are not *** study was to determine whether the endogenous glucose production （EGP）,oral glucose rate of appearance （Ra） and glucose rate of disappearance （Rd） were different in Chinese individuals with prediabetes under fasting conditions and following an oral glucose *** Five subjects with type 2 diabetes,5 subjects with prediabetes and 5 non-diabetic subjects matched for age,weight,fat free mass and body mass index underwent a 180 minute stable glucose isotope tracing （[6,6-2H2] glucose,[1-13C] glucose,and [U-13C] glucose） study under fasting and after ingestion of a 75 g oral glucose *** glucose enrichment was measured by gas chromatography-mass *** sensitivity was estimated using the oral glucose tolerance test （OGTT）-derived insulin sensitivity index,β cell function was determined by the insulinogenic index （△I30/△G30）.Results The insulin sensitivity index （P=0.043） and insulinogenic index （P=0.021） were decreased in subjects with prediabetes compared with *** EGP was slightly higher （P=0.29） and postprandial EGP was comparable in subjects with prediabetes and non-diabetes during 120 minutes after glucose ingestion,but nadir EGP occurred later in prediabetic than non-diabetic *** did not differ among the three *** was substantially lower in subjects with prediabetes than non-diabetes after glucose intake （P=0.013）.Conclusion The mild hyperglycemia observed among individuals with prediabetes may result from decreased Rd during the postprandial state.

关键词： prediabetes glucose metabolism stable isotope triple tracer

Liquid level sensor based on CMFTIR effect in polymer optical fiber

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Photonic Sensors 2016年第4期6卷 312页

作者： Hou, Yulong Liu, Wenyi zhang, huixin Su, Shan Liu, Jia zhang, Yanjun Liu, Jun Xiong, Jijun Ministry of Education Taiyuan 030051 China

The macro-bending induced optical fiber cladding modes frustrated total internal reflection effect is used to realize the liquid level probe with a simple structure of single macro-bend polymer optical fiber loop. The test results show that the extinction ratio reaches 1.06 dB. "First bath" phenomenon is not obvious (about 0.8%). The robustness of the sensor is better, and the ability of anti-pollution is stronger compared with the conventional sensors. The process of making this sensing probe is extremely easy, and the cost is very low.

关键词： Plastic optical fibers

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观亦幻:约翰·阿什伯利诗歌的绘画维度

外国文学研究 2017年第2期39卷 12-19页

作者：张慧馨彭予北京航空航天大学外国语学院

美国当代诗人约翰·阿什伯利把对现实的思考建基于对艺术世界的沉思上。他的诗很难带有非个人化、政治化、情感化的倾向,很多诗都是艺术化的结果,其中尤以绘画为重。他的诗歌创作与绘画犹如孪生,水乳交融,但并不止于对绘画形式天真般的... 详细信息

美国当代诗人约翰·阿什伯利把对现实的思考建基于对艺术世界的沉思上。他的诗很难带有非个人化、政治化、情感化的倾向,很多诗都是艺术化的结果,其中尤以绘画为重。他的诗歌创作与绘画犹如孪生,水乳交融,但并不止于对绘画形式天真般的模仿,而是超越了模仿,展示出与绘画相似的审美意境,其中隐藏着从抽象表现主义画派提取的对无意识的追寻,文本表面的视觉性实为无意识幻觉的呈现,直接指向现实中意义的破碎和主体性的丧失。

关键词：约翰·阿什伯利绘画视觉幻觉