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The mechanism of unexpected reduction of dimethyl pyridine-2,3-dicarboxylate to l,2,3,4-tetrahydrofuro[3,4-b]-pyridin-5(7H)-one with sodium borohydride

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Chinese Chemical Letters 2012年第10期23卷 1122-1124页

作者： Yan Bo Tang qing jian zhang De Quan Yu State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

An unexpected reduction of dimethyl pyridine-2,3-dicarboxylate to 1,2,3,4-tetrahydrofuro[3,4-b]pyridin-5（7H）-one with sodium borohydride in ethanol and tetrahydrofuran, respectively, is described, a hypothetic mecha... 详细信息

关键词： Reduction Sodium borohydride Dimethyl pyridine-2,3-dicarboxylate 1,2,3,4-Tetrahydrofuro[3,4-b]pyridin-5(7H)-one Reactionmechanism

Influence of Direct Current Electric Field on the Formation,Composition and Microstructure of Corrosion Products Formed on the Steel in Simulated Marine Atmospheric Environment

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Acta Metallurgica Sinica(English Letters) 2016年第4期29卷 373-381页

作者： Nian-Wei Dai Jun-Xi zhang Qi-Meng Chen Xin zhang Fa-He Cao jian-qing zhang Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power Shanghai University of Electric Power Department of Chemistry Zhejiang University

X-ray diffraction, Raman spectroscopy and scanning electron microscopy were employed to investigate the effects of the DC electric field on the composition, formation and structure of corrosion products formed on the surface of the steel immersed in NaCl solution. The results show that goethite （α-FeOOH）, akaganeite （β-FeOOH）, lepidocrocite （γ- FeOOH） and magnetite （Fe3O4） are the major constituents among the corrosion products. The arrangement of different levels of the DC electric field intensity gives rise to the following results. The little higher DC electric field intensity （around 100-200 kV/m） promotes the crystallinity and growth of y-FeOOH; obviously, much higher DC electric field intensity （greater than 400 kV/m） prevents the growth of α-FeOOH and facilitates the generation of Fe3O4. Both the promotional growth of γ-FeOOH and suppression of α-FeOOH growth indicated the weakness of the protectiveness of the rust layer. Consequently, the suppression of the transformation of α-FeOOH from y-FeOOH favors the yield of the Fe3O4, which works as a large cathode area and would be about to quicken the subsequent steel corrosion.

关键词： Steel Atmospheric corrosion Rust Electric field Raman spectroscopy

Novel Cylinder Movement Modeling Method Based on Aerodynamics

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1193-1202页

作者： jian-qing zhang Xiao-Mei Hu Jin-Sheng Kang Feng Xiong Ning Zeng School of Mechatronic Engineering and Automation Key Laboratory of Intelligent Manufacturing and RoboticsShanghai University College of Engineering Design and Physical SciencesBrunel University London

The cylinder movement is affected by multiple factors and it is difficult to establish the accurate movement model of the cylinder. In order to improve the reliability of the production line design and to speed up the production line debugging, a novel cylinder movement modeling method based on aerodynamics is proposed. The kinetic theory, thermodynamic theory and kinematics knowledge are applied and integrated various factors which affect the movement characteristics of the cylinder are considered. According to the proposed mathematical model of cylinder movement, thecombined simulation software of cylinder movement based on Visual Studio and Visual Component （3D Create） is developed to calculate thevelocity, accel- eration and movement time of the cylinders during the running of the assembly line. Comparison results of cylinder＇s movement time under different intake air and displacement show that the mathematical model of cylinder movement based on aerodynamic is more accurate and the degree of fittingis 0.9846, which proves the effectiveness of the combined simulation software of cylinder movement. By the cylinder movement modeling method based on aerodynamic, accurate value of takt and the debug parameters can be calculated as a reference for the designers and debuggers of the cylinder-driven assembly lines.

关键词： Aerodynamics Thermodynamics Cylindercharacteristic Combined simulation

A new benzofuranolignan and a new flavonol derivative from the stem of Morus australis

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Chinese Chemical Letters 2008年第2期19卷 196-198页

作者： qing jian zhang Di Zao Li Ruo Yun Chen De Quan Yu The Key laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of Education Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

A new benzofuranolignan austrafuran A （1） and a new flavonol derivative 5,7,2′,4′-tetrahydroxy-3-methoxyflavone （2） were isolated from the stem of Morus australis. Their structures were determined on the basis o... 详细信息

关键词： Morus australis Austrafuran A Flavonol Stilbenoid

Improved spatial filtering velocimetry and its application in granular flow measurement

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Chinese Physics B 2020年第7期29卷 300-307页

作者： Ping Kong Bi-De Wang Peng Wang Zivkovic V jian-qing zhang Shanghai Key Laboratory for Molecular Imaging Shanghai University of Medicine and Health SciencesShanghai 201318China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China School of Medical Instrument and Food Engineering University of Shanghai for Science and TechnologyShanghai 200093China School of Chemical Engineering and Advanced Materials Newcastle UniversityNE17RUUnited Kingdom College of Medical Imaging Shanghai University of Medicine and Health SciencesShanghai 201318China

Spatial filtering velocimetry(SFV)has the advantages of simple structure,good stability,and wide ***,the traditional linear CCD-based SFV method requires an accurate angle between the direction of linear CCD and the direction of moving object,so it is not suitable for measuring a complex flow field or two-dimensional speed in a granular *** this paper,a new extension of spatial filtering method(SFM)based on high speed array CCD camera is proposed as simple and effective technique for measuring two-dimensional speed field of granular *** particular,we analyzed the resolution and range of array CCD-based SFV so that the reader can clarify the application scene of this *** method has a particular advantage for using orthogonal measurement to avoid the angle measurement,which were problematic when using linear CCD to measure the ***,the end-wall effects of the granular flow in rotating drum is studied with different experimental conditions by using this improved technique.

关键词： spatial filtering velocimetry array CCD end-wall effects resolution

Metachronous urothelial carcinoma in the renal pelvis,bladder,and urethra:A case report

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World Journal of Clinical Cases 2023年第13期11卷 3062-3069页

作者： jian-qing zhang Yu Duan Kun Wang Xiao-Li zhang Ke-Hua jiang Department of Urology Guizhou Provincial People’s HospitalGuiyang 550002Guizhou ProvinceChina Department of Biomedicine Guizhou UniversityGuiyang 550025Guizhou ProvinceChina

BACKGROUND Urothelial carcinoma(UC)is a common malignancy of the urinary system that can occur anywhere from the renal pelvis to the proximal *** UCs are in the bladder and have multifocal *** urinary tract UC(UTUC),which occurs in the renal pelvis or ureter,accounts for only 5%to 10%of *** SUMMARY In March 2015,a 70-year-old male who initially presented to a local hospital with a complaint of painless hematuria was diagnosed with UTUC of the right renal *** doctors administered radical nephroureterectomy and bladder cuff *** the doctors recommended intravesical chemotherapy and regular follow-up,he rejected this *** December 2016,the patient presented at our hospital with *** identified UC in the residual bladder and administered radical cystectomy and left cutaneous *** November 2021,he presented again with urethral *** detected urethral UC as the cause of urethral orifice bleeding and administered radical *** then,he has visited regularly for 6-mo follow-ups,and was in stable condition as of December *** UTUC is prone to seeding and *** instillation therapy and intense surveillance are crucial for these patients.

关键词： Upper urinary tract urothelial carcinoma Bladder urothelial carcinoma Urethral urothelial carcinoma Treatment Case report

Deeper Chemical Perceptions for Better Traditional Chinese Medicine Standards

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Engineering 2019年第1期5卷 83-97页

作者： Jin-Jun Hou jian-qing zhang Chang-Liang Yao Rudolf Bauer Ikhlas A. Khan Wan-Ying Wu De-an Guo Shanghai Research Center for Modernization of Traditional Chinese Medicine National Engineering Laboratory for TCM Standardization Technology Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 China Department of Pharmacognosy Institute of Pharmaceutical Sciences Karl-Franzens-Universitat Graz Graz A-8010 Austria National Center for Natural Products Research School of Pharmacy The University of Mississippi University MS 38677 USA

Traditional Chinese medicines (TCMs), a complex system of natural resources with many diverse components, are widely used as approved medicinal agents in China. Quality control of TCMs is a huge challenge for the government and for testing institutes and is associated with numerous scientific issues. Among these considerations include the following questions: How many components are in TCMs? How can the multiple components in TCMs be comprehensively delineated and subsequently characterized? What is the level and range of these (active) metabolites within these multiple-component TCMs, in order to recommend standards? and What are the qualities required for a marker constituent to be selected, and from a practical perspective, how can these components be assessed with low cost and in a short time? All of these factors require significant and deep thinking in order to understand the individualistic chemistry of TCM in order to develop enhanced TCM quality standards for improved and consistent patient care. In this review, the latest exploratory research in TCM chemistry analytical techniques and methods is summarized in order to begin to develop responses to these scientific issues. Advances in these methods have included multidimensional separation for liquid chromatography–high-resolution mass spectrometry (LC–HRMS), smart triggering data-dependent acquisition of LC–HRMS, target analysis with liquid chromatography–mass spectrometry (LC–MS), supercritical fluid chromatography, and data mining of large mass spectrometry (MS) datasets. In addition, two quality strategies have been introduced in order to save reference standards and the analysis time for a TCM quality standard, including the application of the single standard to determine multi-components (SSDMC) and monomethodheterotrait matrix methods. Finally, a series of future improvements for analytical methods for TCMs are proposed.

关键词： Traditional Chinese medicine Liquid chromatography Mass spectrometry Data-dependent acquisition Chemometrics Untargeted Data mining Quality control

The principle of stability control of surrounding rock-bearing structures in high stress soft rock roadways

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Journal of Coal Science & Engineering(China) 2009年第1期15卷 24-27页

作者： WANG Wei-jun ZHU Yong-jian LI Shu-qing zhang Peng Hunan Key Laboratory of Safe Mining Techniques of Coal Mines Xiangtan 411201 China

Through the description of the deformational features of the surrounding rockaround high stress engineering soft rock roadways,the coupling stabilization principle ofinner and outer structures in surrounding rock was put *** supporting principlesof high stress engineering soft rock roadway (high resistance and yielding support,timelysupport,high strength and high stiffness supports) were proposed,which were applied inengineering practices,and obtained better achievements.

关键词： high stress engineering soft rock mass inner and outer structures high resistance and yielding support timely support

Effect of Cobalt Precursor on Microstructures and Visible Light Photoactivity of Doped TiO2 Powders

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Chinese Journal of Chemical Physics 2006年第5期19卷 463-468页

作者： Jing-ying Shi Wen-hua Leng jiang-lin Cao jian-qing zhang Chu-nan Cao Department of Chemistry Yuquan Campus Zhejiang University Hangzhou 310027 China Department of Chemistry Quanzhou Normal College Quanzhou 352000 China

In order to develop photoactive cobalt-doped TiO2 for the degradation of organic pollutants using visible light irradiation, the effects of cobalt precursor on TiO2 microstructure were investigated. Three cobaltprecursors, i.e. COCl2, Co（NO3）2 and COSO4 with two doping levels （nominally 1% and 10%）, and two annealing temperatures （400 and 800 ℃） were adopted to prepare tile doped titania through the sol-gel method. The powder samples were characterized with XRD, SEM, BET surface area analysis and UV-Vis absorption spectroscopy, and their photocatalytic activities were evaluated by the degradation of aniline under visible light irradiation. The results showed that the distribution of titania phases, particle size, morphology, surface area and the optical absorption of the catalysts were greatly dependent on the cobalt precursors. Samples prepared from Co（NO3）2, especially for those doped at 1% and calcined at 400 ℃, showed the highest photocatalytic activity towards the degradation of aniline, and the possible reasons are discussed briefly.

关键词： Cobalt precursor Doped titania Photocatalysis Visible light