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Synthesis and Crystal Structure of (2S,2'S,4'R)-2-(1-Hydroxy-1-ethylpropyl)-1-[(1'-p-tosyl-4'-hydroxypyrrolidin-2'-yl)methyl]pyrrolidine

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1203-1208页

作者： FU Yu-Qin DING Li-Na zhang sheng-hong TAO Jing-Chao ZHU Yu Department of Chemistry New Drug Research ＆ Development Center Zhengzhou University Zhengzhou 450052 China

The title compound （2S,2＇S,4＇R）-2-（1-hydroxy-1-ethylpropyl）-1-[（1＇-p-tosyl-4＇- hydroxypyrolidin-2＇-yl）methyl]pyrrolidine synthesized by using （2S,4R）-4-hydroxy-L-proline and L-proline as the main materials was characterized through IR, ^1H NMR, ^13C NMR and HRMS spectra as well as single-crystal X-ray diffraction analysis. There is one equivalent ethanol involved in the crystal （C23H40N2O5S, Mr = 456.63）. The crystal belongs to the triclinic system, space group P1, a = 6.5628（13）, b = 8.4228（17）, c = 11.957（2）°A, α= 80.54（3）,β= 83.19（3）, γ= 89.89（3）°, V= 647.3（2） °A^3, Z = 1, D, = 1.171 g/cm^3, λ（MoKα） = 0.71073°A,β = 0.158 mm^-1, F（000） = 248, the final R = 0.0465 and wR = 0.1336 for 1769 observed reflections with I〉 2σ（I）. The adjacent molecules of compound 5 are linked through intermolecular hydrogen bonds formed by the secondary hydroxy group of one molecule with the tertiary hydroxy group of another one, and the molecular chains are further linked by ethanol through two kinds of hydrogen bonds with two molecules from different chains respectively to form a supramolecular structure.

关键词： proline derivative chiral amino alcohol synthesis crystal structure

The Characteristics of Turbulence Structure and Transfer over the Middle Area of the Tibetan Plateau

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Atmospheric and Oceanic Science Letters 2013年第2期6卷 67-73页

作者： LI Fu-Yu LI Xiao-Lan zhang hong-sheng Department of Atmospheric and Oceanic Sciences & Laboratory for Climate and Ocean-Atmosphere Studies Peking University

In this paper, turbulent data obtained from the Damxung site during the Secondary Tibetan Plateau Science Experiment (TIPEX) in 1998 are used to study the characteristics of the turbulent spectra, turbulence transport, and the dissipation rates of turbulent kinetic energy, temperature variance, and humidity variance in the middle area of the Tibetan Plateau. The turbulent spectra of wind velocity, potential temperature, and humidity satisfy the-2/3 power law in the high frequency range. Horizontal transportation of heat and water vapor is negligible compared with vertical transportation under strong unstable conditions, and as the stability parameter z/L increases (where z is the observational height, and L is the Monin Obukhov length), horizontal transportation becomes dominant under near-neutral, neutral, and stable conditions. The non-dimensional temperature and humidity variances are 20% less than the temperature and humidity gradient variances. These deficits appear to increase as the absolute stability parameter increases. Moreover, the effects of turbulence transportation and pressure variance exist throughout the entire stability region.

关键词： turbulence structure turbulence transfer dissipation rate observational method Tibetan Plateau

NUMERICAL SIMULATION OF SUMMER CIRCULATION IN THE EAST CHINA SEA AND ITS APPLICATION IN ESTIMATING THE SOURCES OF RED TIDES IN THE YANGTZE RIVER ESTUARY AND ADJACENT SEA AREAS

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Journal of Hydrodynamics 2007年第3期19卷 272-281页

作者： CHEN Xiu-hua ZHU Liang-sheng zhang hong-sheng South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China College of Traffic and Communications South China University of Technology Guangzhou 510641 China School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200030 China

Based on the COHERENS （a Coupled Hydrodynamical Ecological model for Regional Shelf seas）, a three-dimensional baroclinic model for the summer of East China Sea （ECS） was established with the sigma-coordinate in the vertical direction and spherical coordinate in the horizontal direction. The circulation patterns of the Kuroshio Current, the Taiwan Warm Current （TWC）, the Tsushima Current and the Yangtze Diluted Water （YDW） were successfully simulated with this model. The calculated results are fairly consistent with previous observations and studies. Based on this baroclinic current field, the Lagranian particles tracking was simulated to estimate the possible origins of the red tides frequently occurring in the Yangtze River estuary and its adjacent sea areas. If there are ＂seeds＂（cysts） of the red tide algae at the seabed of the Taiwan Strait, the offshore of Fujian and Zhejiang Provinces and the northeast Taiwan Island, those are extremely possible sources of the red tides in the Yangtze River estuary and its adjacent sea areas. Field data are needed to confirm it. Numerical simulation to estimate the source of the red tides is a new application of the Lagrangian transport in the marine ecology.

关键词： East China Sea (ECS) Yangtze River estuary,numerical simulation COHEERNS Lagrangian transport red tide the source of the red tides

Identification and Expression Analysis of the Phosphoenolpyruvate Carboxylase Gene Family in Peanut (Arachis hypogaea L.)

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Agricultural Sciences in China 2010年第4期9卷 477-487页

作者： YU Shan-lin PAN Li-juan YANG Qing-li CHEN Ming-na zhang hong-sheng State Key Laboratory of Crop Genetics and Germplasm Enhancement Nanjing Agricultural University Nanjing 210095 P.R.China Shandong Peanut Research Institute Qingdao 266100 P.R.China

Phosphoenolpyruvate carboxylase （PEPC） is widely distributed in plants and bacteria, and catalyzes the carboxylation of phosphoenolpyruvate to form oxaloacetate and inorganic phosphate. To investigate the molecular mechanisms of the regulation and control of peanut oil, with the degenerated primers and RACE-PCR approach, five PEPC genes were cloned from peanut, and designated as AhPEPC1, AhPEPC2, AhPEPC3, AhPEPC4, and AhPEPC5, respectively. The structure and phylogenetic analysis of PEPC protein indicated that AhPEPC1-4 genes encoded a typical plant-type PEPC-enzyme, and AhPEPC5 a bacterial-type. By real-time quantitative RT-PCR approach the expression pattern of each gene was detected in various tissues of normal and high oil-content peanut varieties. It was found that there was a lower expression level of AhPEPCs genes except for the AhPEPC2 in high-oil peanut than normal-oil peanut line. The results provide some fundamental information for the further investigation of plant PEPC proteins and their role in regulation of oil-content in peanut seeds.

关键词： peanut phosphoenolpyruvate carboxylase gene cloning expression pattern regulation of oil-content

Clinical Observation on Dong's Extraordinary Points for Tinnitus Due to Cervical Spondylosis

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Journal of Acupuncture and Tuina Science 2013年第5期11卷 300-302页

作者： zhang sheng-hong Wu Yao-chi Chen Jie hong Jue No.6 People’s Hospital Affiliated to Shanghai Jiaotong University Jiading District Hospital of Traditional Chinese Medicine

Objective:To observe the clinical efficacy of Dong’s extraordinary points in treating tinnitus due to cervical ***:Totally 140 eligible subjects diagnosed with tinnitus due to cervical spondylosis were randomized into two groups,seventy in the treatment group were intervened by acupuncture at Dong’s extraordinary points;seventy in the control group were intervened by acupuncture at cervical Jiaji(EX-B 2)and distal points on *** efficacy was observed after a treatment ***:The total effective rate was 95.7%in the treatment group versus85.7%in the control group,and the difference was statistically significant(P<0.05).Conclusion:Compared to traditional point selection,acupuncture at Dong’s extraordinary points has advantages of fewer points,less pain,faster effect,and better therapeutic efficacy.

关键词： Acupuncture Therapy Spondylosis Neck Pain Tinnitus

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一种数控等离子切割烟尘回收装置

建材世界 2024年第5期45卷 52-54页

作者：徐伟王士池张宏盛赵天成蚌埠凯盛工程技术有限公司蚌埠233010

现代工业生产领域中,与传统火焰切割技术相比较,数控等离子切割技术在金属板材加工环节展现出更高的切割精度与更快的作业速度,因而在机械制造业中的应用日渐普及。然而,大型数控等离子切割设备在切割钢铁材料过程中会释放大量的切割粉... 详细信息

现代工业生产领域中,与传统火焰切割技术相比较,数控等离子切割技术在金属板材加工环节展现出更高的切割精度与更快的作业速度,因而在机械制造业中的应用日渐普及。然而,大型数控等离子切割设备在切割钢铁材料过程中会释放大量的切割粉尘,这些粉尘自工件下方向外喷散,导致车间内烟尘弥漫,工作环境恶化。为有效保护劳动者健康,优化工作环境,提升生产效率,公司已依照环境保护标准,对运行中的两台数控等离子切割机实施了烟尘处理及设备改良措施,并已取得显著成果。

关键词：空气等离子切割除尘脉冲式滤筒

Hydrogel loaded with bone marrow stromal cell-derived exosomes promotes bone regeneration by inhibiting inflammatory responses and angiogenesis

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World Journal of Stem Cells 2024年第5期16卷 499-511页

作者： Shuai zhang Chuan Lu sheng Zheng Guang hong Division for International Collaborative and Innovative Dentistry Tohoku University Graduate School of DentistrySendai 980-8575MiyagiJapan School of Stomatology Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina

BACKGROUND Bone healing is a complex process involving early inflammatory immune regu-lation,angiogenesis,osteogenic differentiation,and *** repair poses challenges for orthopedic surgeons,necessitating the search for efficient healing *** To investigate the underlying mechanism by which hydrogel-loaded exosomes derived from bone marrow mesenchymal stem cells(BMSCs)facilitate the process of fracture *** Hydrogels and loaded BMSC-derived exosome(BMSC-exo)gels were charac-terized to validate their *** vitro evaluations were conducted to assess the impact of hydrogels on various stages of the healing *** could recruit macrophages and inhibit inflammatory responses,enhance of human umbilical vein endothelial cell angiogenesis,and promote the osteogenic differen-tiation of primary cranial ***,the effect of hydrogel on fracture healing was confirmed using a mouse fracture *** The hydrogel effectively attenuated the inflammatory response during the initial repair stage and subsequently facilitated vascular migration,promoted the formation of large vessels,and enabled functional vascularization during bone *** effects were further validated in fracture *** We successfully fabricated a hydrogel loaded with BMSC-exo that modulates macrophage polarization and angiogenesis to influence bone regeneration.

关键词： Hydrogel Bone marrow mesenchymal stem cells Macrophage polarization Angiogenesis Bone regeneration

Preparation of Optically Active Alkoxy-serines from Amino-amide Racemate Catalyzed by Escherichia coli Cells with Peptidase B Activity

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Chemical Research in Chinese Universities 2013年第1期29卷 95-98页

作者： WANG Zhi-yuan LIU Jun-zhong XU Li-sheng zhang hong-juan LIU Qian JIAO Qing-cai State Key Laboratory of Pharmaceutical Biotechnology School of Life Science Nanjing University Nanjing 210093 P. R. China

Alkoxy-L-serines are useful for peptide syntheses. The demand for alkoxy-L-serines in the pharmaceutical industries continues to increase because of their multiple physiological effects. In this research, an improved method for alkoxy-L-serines synthesis is reported. A series of substrates, DL-fl-alkoxy-a-amino propionamides, was used for the synthesis of alkoxy-serines catalyzed by Escherichia coli cells with peptidase B（PepB） activity. The results show that PepB has a high resolution activity with DL-fl-alkoxy-a-amino propionamides as substrate. Reaction conditions were optimized, i.e., DL-β-methoxy-a-amino propionamide as substrate at pH=9.0, 40 ℃ and 14 h, and the optimal reaction concentration is 400 mmol/L. The results also show that divalent metal cations exhibit different effects on the PepB activity, for example, Zn2＋ and Cu2＋ can obviously inhibit the activity of PepB, whereas Co2＋, Ca2＋, Mn〉 and Mg2＋ at low concentrations can activate PepB. This research provides access to enantiomerically enriched and valuable alkoxy-L-serines from a simple amino-amide racemate.

关键词： Alkoxy-serine DL-β-Alkoxy-a-amino propionamide Enzymatic resolution Peptidase B

Attaining synergetic equilibrium of electrical conductivity and tensile strength in GQDs@GN/Cu composites through multi-scale intragranular and intergranular reinforcements

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Rare Metals 2024年第1期43卷 366-379页

作者： Shuang-Yin zhang Liang Liu Rui Bao Jian-hong Yi sheng-Da Guo Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Key Laboratory of Advanced Materials of Yunnan Province Kunming University of Science and TechnologyKunming 650093China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China

The configuration and quality of reinforcements, as well as the robustness of interfacial bonding,holding a critical significance in determining the concurrence between electrical conductivity and mechanical strength in metal matrix composites. In this study, citric acid was employed as the precursor for synthesizing multiscale carbon nanomaterials(graphene quantum dots and graphene, abbreviated as GQDs and GN). The GQDs@GN/Cu composites were fabricated through a segmented ball milling process in conjunction with subsequent spark plasma sintering(SPS). The intragranular GQDs and intergranular GQDs@GN had synergistically reinforced Cu composites through Orowan strengthening, load transfer strengthening and refinement strengthening. Furthermore,the robust interface bonding between GQDs@GN and Cu effectively mitigated interfacial impedance stemming from electron-boundary scattering. The yield strength and ultimate tensile strength of the GQDs@GN/Cu composites were recorded as 270 and 314 MPa, respectively, representing an improvement of 92 and 28% over pure Cu, while maintaining electrical conductivity at a level comparable to that of pure Cu. This study advances the understanding of the possibility of realizing a synergistic compatibility between electrical conductivity and mechanical strength in Cu composites.

关键词： Cu matrix composites Interface bonding Mechanical property Graphene quantum dots(GQDs) Electrical conductivity