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Novel synthesis of 2-butyl-5-chloro-3H-imidazole-4-carbaldehyde:A key intermediate of Losartan

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Chinese Chemical Letters 2009年第3期20卷 269-270页

作者： Hai Bo Sun Guo Jun Zheng Ya Ping wang xiang jing wang Wen Sheng xiang College of Life Science Northeast Agricultural University Harbin 150030 China Zhejiang Hisun Pharmaceutical Co. Ltd. Taizhou 318000 China

A novel method for synthesis of 2-butyl-5 -chloro-3H-imidazole-4-carbaldehyde 2, a key intermediate of Losartan was reported. The compound 2 was synthesized from starting material dimethyl malonate 6 and n-valeronitrile 8 by six steps with an overall yield of 40%. The key step including the reaction of compound 5 with POCl3/DMF followed by hydrolysis to give compound 2 with the yield of 68%.

关键词： Losartan Antihypertensive Angiotensin II 2-Butyl-5-chloro-3H-imidazole-4-carbaldehyde

Practical synthesis of methyl(E)-2-(3-(3-(2-(7-chloro-2- quinolinyl)ethenyl)phenyl)-3-oxopropyl)benzoate,a key intermediate of Montelukast

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Chinese Chemical Letters 2012年第5期23卷 518-520页

作者： Liang He Yang Hui Guo Ya Ping wang xiang jing wang Ji Zhang Wen Sheng xiang Department of Biochemical Engineering Northeast Agricultural UniversityHarbin 150030China Zhejiang Hisun Pharmaceutical Co. Ltd.Taizhou 318000China

A novel and practical synthetic route is presented for the preparation of methyl-（E）-2-（3-（3-（2-（7-chloro-2-quinolinyl）ethenyl） phenyl）-3-oxopropyl）benzoate,the key intermediate of Montelukast,a leukotriene *** main diarylpropane framework was prepared via a polarity conversation reaction resulting in an acyl anion equivalent followed by a nucleophilic substitution *** overall yield of this approach was 61%.This method is simple for operation and suitable for industrial production.

关键词： Montelukast Synthesis Intermediate Polarity conversion

Improved and efficient synthesis of Maxacalcitol

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Chinese Chemical Letters 2014年第5期25卷 771-774页

作者： Shi Feng Li-Fei Cui He-Geng Wei Guo-Jun Zheng Ya-Ping wang xiang-jing wang Ji Zhang Wen-Sheng xiang College of Science Northeast Agricultural University School of Life Science Northeast Agricultural University Harbin FRP Institute Zhejiang Hisun Pharmaceutical Co. Ltd.

Maxacalcitol,the 22-oxa-derivative of 1a,25-dihydroxyvitamin D3,has been used as an antihyperparathyroidism and antipsoriatic *** this paper,an alternative synthetic route has been developed using commercially available vitamin D2as the starting *** addition,as a key intermediate,the asymmetric synthesis of 20（S）-alcohol 14 with the chiral auxiliary（R-CBS） was described for the first *** new synthetic route afforded Maxacalcitol with improved overall yield（13.9%） in eleven steps.

关键词： Vitamin D3 derivative Maxacalcitol Synthesis Asymmetric reduction

Differentiation and tumorigenicity of neural stem cells from human cord blood mesenchymal stem cells

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Neural Regeneration Research 2009年第10期4卷 769-774页

作者： jing xiang Changming wang jingzhou wang Department of Neurology Research Institute of Surgery Daping Hospital Third Military Medical University of Chinese PLA Chongqing 400042 China

BACKGROUND： Mesenchymal stem cells （MSCs） are capable of differentiating into a variety of tissues and exhibit low immunogenicity. OBJECTIVE： To investigate isolation and in vitro cultivation methods of human cord blood MSCs, to observe expression of neural stem cell （NSC） marker mRNA under induction, and to detect tumorigenicity in animals. DESIGN, TIME AND SETTING： A cell biological, in vitro trial and a randomized, controlled, in vivo experiment were performed at the Department of Neurology, Daping Hospital at the Third Military Medical University of Chinese PLA from August 2006 to May 2008. MATERIALS： Umbilical cord blood was collected from full-term-delivery fetus at the Department of Gynecology and Obstetrics of Daping Hospital, China. Eighteen BALB/C nu/nu nude mice were randomly assigned to three groups： back subcutaneous, cervical subcutaneous, and control, with 6 mice in each group. METHODS： Monocytes were isolated from heparinized human cord blood samples by density gradient centrifugation and then adherent cultivated in vitro to obtain MSC clones. After the cord blood MSCs were cultured for 7 days with nerve growth factor and retinoic acid to induce differentiation into NSCs, the cells （adjusted density of 1 × 10^7/mL） were prepared into cell suspension. In the back subcutaneous and cervical subcutaneous groups, nude mice were hypodermically injected with a 0.5-mL cell suspension into the back and cervical regions, respectively. In the control group, nude mice received a subcutaneous injection of 0.5 mL physiological saline into the back or cervical regions, respectively. MAIN OUTCOME MEASURES： Cellular morphology was observed by inverted microscopy, cultured cord blood MSCs were examined by flow cytometry, expression of nestin and musashi-1 mRNA was detected by reverse-transcriptase polymerase chain reaction prior to and after induction, and tumorigenicity following cord blood MSC transplantation was assayed by hematoxylin-eosin staining. RESULTS： Follo

关键词： cord blood mesenchymal stem cells neural stem cells induced differentiation nestin tumorigenicity

Infrared spectra of soluble polytoluidines

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Acta Chimica Sinica English Edition 1989年第1期7卷 53-58页

作者： wang Li-xiang jing Xia-Bin wang Fo-Song Changchun Institute of Applied Chemistry,Academia Sinica Changchun Institute of Applied Chemistry Academia Sinica

IR spectra of soluble poly-o-toluidine(POT)and poly-m-toluidine(PMT)have been *** assignment of their IR spectra is given by comparing their spectra in HCI and I_2 doped states and in subsequently NH_3 dedoped state w... 详细信息

关键词： HCI

SNR WALL AND COOPERATIVE SPECTRUM SENSING IN COGNITIVE RADIO UNDER NOISE UNCERTAINTY

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Journal of Electronics(China) 2010年第5期27卷 611-617页

作者： wang Haijun Su Xin Xu Yi Chen xiang wang jing Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100084China

Cooperative energy spectrum sensing has been proved effective to detect the spectrum holes in Cognitive Radio(CR).However,its performance may suffer from the noise uncertainty,which is portrayed by the SNR wall in some *** this paper we analyze the spectrum sensing per-formance under noise uncertainty and find an alternative approach to obtain the SNR *** the average SNR wall is proposed to illustrate the statistically average impact of noise *** addition,the cooperative sensing performance under noise uncertainty with AND rule is *** and numerical results show that cooperative sensing can significantly improve the sensing performance under the condition of noise uncertainty.

关键词： Cooperative spectrum sensing Noise uncertainty SNR wall

Hierarchically Porous Polypyrrole Foams Contained Ordered Polypyrrole Nanowire Arrays for Multifunctional Electromagnetic Interference Shielding and Dynamic Infrared Stealth

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Nano-Micro Letters 2025年第4期17卷 399-418页

作者： Yu-long Liu Ting-yu Zhu Qin wang Zi-jie Huang De-xiang Sun jing-hui Yang Xiao-dong Qi Yong wang School of Chemistry Key Laboratory of Advanced Technologies of Materials(Ministry of Education)Southwest Jiaotong UniversityChengdu 610031People’s Republic of China

As modern communication and detection technologies advance at a swift pace,multifunctional electromagnetic interference(EMI)shielding materials with active/positive infrared stealth,hydrophobicity,and electric-thermal conversion ability have received extensive *** the aforesaid requirements simultaneously remains a huge *** this research,the melamine foam(MF)/polypyrrole(PPy)nanowire arrays(MF@PPy)were fabricated via one-step electrochemical *** hierarchical MF@PPy foam was composed of three-dimensional PPy micro-skeleton and ordered PPy nanowire *** to the upwardly grown PPy nanowire arrays,the MF@PPy foam possessed good hydrophobicity ability with a water contact angle of 142.00°and outstanding stability under various harsh ***,the MF@PPy foam showed excellent thermal insulation property on account of the low thermal conductivity and elongated ligament characteristic of PPy nanowire ***,taking advantage of the high conductivity(128.2 S m^(-1)),the MF@PPy foam exhibited rapid Joule heating under 3 V,resulting in dynamic infrared stealth and thermal camouflage *** importantly,the MF@PPy foam exhibited remarkable EMI shielding effectiveness values of 55.77 dB and 19,928.57 dB cm^(2)g^(-1).Strong EMI shielding was put down to the hierarchically porous PPy structure,which offered outstanding impedance matching,conduction loss,and multiple *** innovative approach provides significant insights to the development of advanced multifunctional EMI shielding foams by constructing PPy nanowire arrays,showing great applications in both military and civilian fields.

关键词： Polypyrrole nanowire arrays Hierarchical foam Hydrophobicity Infrared stealth Electromagnetic interference shielding

Unifying Fixed Time and Prescribed Time Control for Strict-Feedback Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 347-355页

作者： xiang Chen Yujuan wang Yongduan Song the State Key Laboratory of Power Transmission Equipment & System Security and New Technology and School of Automation Chongqing University IEEE

This paper investigates the prescribed-time tracking control problem for a class of multi-input multi-output(MIMO)nonlinear strict-feedback systems subject to non-vanishing uncertainties. The inherent unmatched and non-vanishing uncertainties make the prescribed-time control problem become much more nontrivial. The solution to address the challenges mentioned above involves incorporating a prescribed-time filter, as opposed to a finite-time filter, and formulating a prescribed-time Lyapunov stability lemma(Lemma 5). The prescribed-time Lyapunov stability lemma is based on time axis shifting time-varying yet bounded gain, which establishes a novel link between the fixed-time and prescribed-time control method. This allows the restriction condition that the time-varying gain function must satisfy as imposed in most exist prescribed-time control works to be removed. Under the proposed control method, the desire trajectory is ensured to closely track the output of the system in prescribed time. The effectiveness of the theoretical results are verified through numerical simulation.

关键词： Prescribed-time control prescribed-time filter robust control state feedback strict-feedback systems

Environmental Inequality in China’s Urban Expansion:A Case Study of Guangzhou,China

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Chinese Geographical Science 2025年第1期35卷 187-202页

作者： wang Shaogu SHEN jing School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510006China

Environmental inequality is a prevalent issue in developing countries undergoing urban *** expansion induces the formation and evolution of environmental inequality by creating environmental and structural conditions that lead to the spatial relocation of environmental hazards and the socio-spatial segregation of different groups in developing *** study investigated the spatial patterns and temporal trends of environmental inequality under urban expansion in Guangzhou,a megacity in *** considered how environmental disparities and socio-demographic attributes interact in terms of industrial pollution exposure using additive semiparametric quantile regression,combined with spatial visualisation,on the basis of the economic and population census data from 1990 to *** study revealed that urban expansion sparked the spatial displacement of environmental risks and the social-spatial differentiation,exposing the peripheral regions and disadvantaged groups to higher environmental risks.A reciprocal transformation occurred between central and peripheral regions,as well as a process of redistributing environmental risks across social *** the context of urban expansion in developing countries,the causes of environmental inequality shifted from individual socio-economic differences to structural factors,such as industrial layout and social division of labour in cities,leading to the spatial displacement and concealment of environmental *** study provides insights and guidance for policymakers to address the issue of environmental inequality in the context of urban expansion.

关键词： environmental inequality urban expansion spatiotemporal evolution additive semiparametric quantile regression Guangzhou,China