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Synthesis and Crystal Structure of 5-N-i-Propyl-2-(2′-nitrobenzenesulfonyl)-glutamine

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Chemical Research in Chinese Universities 2006年第6期22卷 760-762页

作者： XIAO yong-jun wang jian-guo wang Bao-lei LI Zheng-ming SONG Hai-bin Elemento-Organic Chemistry Institute State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

The title compound, 5 -N-i-propyl-2-（2＇ -nitrobenzenesulfonyl）-glutamine, was synthesized and its structure was confirmed by IB, MS, ^1H NMB, and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P2（ 1 ）, with a =0. 69281 （ 11 ） nm, b = 0. 76508（12）, c = 1. 5843（3） nm, α=90°, β =90. 941 （3）°, γ =90°, V=0. 8397（2） nm^3, Z =-2, Dc = 1.477 g/cm^3,μ =0. 236 mm^-1, F（000） =392, R =0. 0297, and wR=0.0664.

关键词： 5 -N-i-Propyl-2-( 2' -nitrobenzenesulfonyl) -glutamine Synthesis Crystal structure

Epigallocatechin-3-gallate attenuates lipopolysaccharideinduced inflammation in human retinal endothelial cells

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International Journal of Ophthalmology(English edition) 2014年第3期7卷 408-412页

作者： Hui-Yan Zhang jian-yong wang Hang-Ping Yao Hangzhou Vocational & Technical College Department of Ophthalmology the First Affiliated HospitalSchool of Medicine Zhejiang University State Key Laboratory for Diagnosis and Treatment of Infectious Diseases the First Affiliated Hospital School of Medicine Zhejiang University

AIM:To investigate the mechanism underlying the anti-inflammatory effects of epigallocatechin-3-gallate(EGCG)in lipopolysaccharide(LPS)-stimulated human retinal endothelial cells(HRECs).METHODS:HRECspre-treatedwithEGCG(0-100μmol/L)were stimulated with LPS(250 ng/mL).Levels of tumor necrosis factor alpha(TNF-α),vascular endothelial growth factor(VEGF),monocyte chemotactic protein-1(MCP-1)and nitric oxide(NO)in the supernatants were determined by enzyme-linked immunosorbent assay(ELISA)and Griess *** protein expression of phosphorylated extracellular signal-regulated kinase(ERK)1/2 and p38 mitogen-activated protein kinases(p38)were determined by Western blot ***:EGCG pre-treatment significantly inhibited the secretion of TNF-α,VEGF,MCP-1 and NO in LPSstimulated ***,EGCG effectively attenuated LPS-induced activation and phosphorylation of ERK1/2 and p38 in HRECs in a dose-dependent ***:EGCG exhibited inhibitory effects on LPS-induced pro-inflammatory cytokines production by modulating ERK1/2 and p38 pathways in HRECs,suggesting EGCG as a potential candidate for antiinflammatory intervention.

关键词： epigallocatechin-3-gallate human retinal endothelial cells inflammatory factors

MGB probe assay for rapid detection of mtDNA11778 mutation in the Chinese LHON patients by real-time PCR

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第8期9卷 610-615页

作者： jian-yong wang Yang-shun GU Jing wang Yi TONG Ying wang Jun-bing SHAO Ming QI Department of Ophthalmology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Department of Ophthalmology the First Affiliated Hospital Fujian Medical University Fuzhou 325000 China Department of Ophthalmology Eye Hospital Academy of Chinese Medical Science Beijing 100040 China Institute of Biotechnology Shanghai Zhijiang Biotech Incorporation Shanghai 210038 China Institute of Genome Sciences University of Rochester Medical Center Rochester NY 14642 USA

Objective： Leber＇s hereditary optic neuropathy （LHON） is a maternally inherited degeneration of the optic nerve caused by point mutations of mitochondrial DNA （mtDNA）. Many unsolved questions regarding the penetrance and pathophysiological mechanism of LHON demand efficient and reliable mutation testing. This study aims to develop a minor groove binder （MGB） probe assay for rapid detection of mtDNA11778 mutation and heteroplasmy in Chinese LHON patients by real-time polymerase chain reaction （PCR）. Methods： Forty-eight patients suspected of having LHON and their maternal relatives underwent a molecular genetic evaluation, with 20 normal individuals as a control group at the same time. A real-time PCR involving two MGB probes was used to detect the mtDNA 1 1778 mutation and heteroplasmy. A linear standard curve was obtained by pUCmLHONG and pUCmLHONA clones. Results： All 48 LHON patients and their maternal relatives were positive for rntDNA11778 mutation in our assay, 27 heteroplasmic and 21 homoplasmic. Eighteen cases did not show an occurrence of the disease, while 9 developed the disease among the 27 heteroplasmic mutation cases. Eleven did not show an occurrence of the disease, while 10 cases developed the disease among 21 homoplasmic mutation cases. There was a significant difference in the incidence between the heteroplasmic and the homoplasmic mutation types. The time needed for running a real-time PCR assay was only 80 min. Conclusion： This real-time PCR assay is a rapid, reliable method for mtDNA mutation detection as well as heteroplasmy quantification. Detecting this ratio is very important for predicting phenotypic expression of unaffected carriers.

关键词： Leber's hereditary optic neuropathy (L HON) Mitochondrial DNA (mtDNA) MtDNA 11778 mutation Minor groove binder (MGB) orobe. Real-time oolvmerase chain reaction (PCR)

Solidification Properties of CaO-SiO_2-TiO_2 Based Mold Fluxes

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Journal of Iron and Steel Research International 2011年第7期18卷 15-19,52页

作者： HE Sheng-ping HUANG Qing-yun ZHANG Guo-xing LU yong-jian wang Qian Chongqing Key Laboratory of Metallurgical Engineering College of Materials Science and EngineeringChongqing University Chongqing 400044 China

In continuous casting of peritectic steel grades sensitive to longitudinal cracking, the solidification properties of mold fluxes play an important role in keeping smooth running of continuous casting process and achieving high surface quality of casting strands. To reduce fluorine pollution in molten slag, types of CaO-SiO2-TiO2 （CTS） based mold fluxes were investigated. The solidification and crystallization properties, including viscosity η at 1 573 K, break temperature Tbr, crystallization ratio Rc and solidification mineragraphy were measured, which were compared with those of CaO-SiO2-CaF2 based mold fluxes. The experiments show that there are unstable viscosity-high tem- perature properties and high Tbr in part of CTS slag system, which are bad for lubrication between liquid flux film and strand. And when temperature is below Tbr, the viscosities change slowly during cooling in some part of this slag system, which imply that liquid mold fluxes solidify slowly and it is easy to cause surface longitudinal cracks on strand. Major mineragraphy of the CaO-SiO2-TiO2 based mold fluxes are CaO · TiO2 or CaO · TiO2 and CaO · SiO2 · TiO2. TiN and Ti（C,N） can be formed in mold fluxes bearing high TiO2 during the continuous casting.

关键词： mold flux solidification property peritectic steel mineragraphy

Ramet Population Structure of Fargesia nitida （Mitford） Keng f. et Yi in Different Successional Stands of the Subalpine Coniferous Forest in Wolong Nature Reserve

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Journal of Integrative Plant Biology 2006年第10期48卷 1147-1153页

作者： Xiao-Hong Yu jian-Ping Tao Yuan Li yong-jian wang Yi Xi Wei-Yin Zhang Run-Guo Zang Key Laboratory of Eco-environments of Three Gorges Reservoir Region Ministry of Education School of Life Sciences Southwest University Chongqing 400715 China Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing 100091 China

Forest structure and succession in Wolong Nature Reserve is influenced by the understory dwarf bamboo population. However, less is known about how the forest succession affects the dwarf bamboo population. To examine the bamboo ramet population growth of Fargesla nitida （Mltford） Keng f. et Yi and to determine how ramet population structure varies along the succession of coniferous forest, we sampled ramet populations of F. nitida from the following three successional stages：（i） a deciduous broad-leaved （BL） stand; （ii） a mixed broad-leaved coniferous （MI） stand; and （ill） a coniferous （CF） stand. We investigated the population structure, biomass allocation, and morphological characteristics of the bamboo ramet among the three stand types. Clonal ramets, constituting the bamboo population, tended to become short and small with succession. The ramet changed towards having a greater mass investment in leaves, branches and underground roots and rhizomes rather than in the culm. With respect to leaf traits, individual leaf mass and area in the BL stand were markedly bigger than those In both the MI and CF stands, except for no significant difference in specific leaf area. The age distribution showed that the bamboo population approached an older age with succession. The results demonstrate that the ramet population structure of F. nitida is unstable and its growth performance is inhibited by succession.

关键词： coniferous forest Fargesia nitida ramet population structure succession Wolong Nature Reserve

Three-dimensional reconstruction of precession warhead based on multi-view micro-Doppler analysis

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Journal of Systems Engineering and Electronics 2024年第3期35卷 541-548页

作者： ZHANG Rongzheng wang yong MAO jian School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China Laboratory of Pinghu Pinghu 314200China

The warhead of a ballistic missile may precess due to lateral moments during release. The resulting micro-Doppler effect is determined by parameters such as the target's motion state and size. A three-dimensional reconstruction method for the precession warhead via the micro-Doppler analysis and inverse Radon transform(IRT) is proposed in this paper. The precession parameters are extracted by the micro-Doppler analysis from three radars, and the IRT is used to estimate the size of targe. The scatterers of the target can be reconstructed based on the above parameters. Simulation experimental results illustrate the effectiveness of the proposed method in this paper.

关键词： time-frequency analysis inverse Radon transform(IRT) precession warhead

Asymmetric reversible structural switching of a diene coordination polymer promoted by UV-visible light

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Science China Chemistry 2024年第2期67卷 536-541页

作者： yong wang Qiaoqiao Zhang yong-yong Cao Qi Liu Brendan F.Abrahams jian-Ping Lang College of Chemistry Chemical Engineering and MaterialsSoochow UniversitySuzhou215123China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China College of Biological Chemical Science and EngineeringJiaxing UniversityJiaxing314001China School of Chemistry University of MelbourneVictoria3010Australia

In natural and artificial systems,reversible reactions are commonly asymmetric with respect to the time scale and nature of the stimuli which drive the forward and backward *** applications for which switching behavior is required,it is desirable that the reversible reaction goes as close to symmetric as possible;however,such systems are ***,we report an example of ultraviolet(UV)-visible light-regulated asymmetric reversible structural switching involving a diene-based coordination polymer,CP1 and its monocyclobutane product,*** is possible to cycle at least ten times through a forward [2+2] photocycloaddition reaction and the reverse,photocleavage reaction.A single cycle can be completed within a few *** transformation is accompanied by fast and distinct fluorescence changes,arising from optimisation of the reaction *** functional theory calculations allow rationalisation of the asymmetric reversible transformation between CP1 and CP1a rather than between CP1 and its dicyclobutane product *** work provides a clear illustration of reversible structural switching which approaches symmetric behaviour with respect to reaction rate and *** insights gained from this work also assist in the design of fast,reversible switching materials.

关键词： asymmetrical reversible structural switching coordination polymer photocycloaddition UV-visible light-controlled fluorescence switching

Clonal integration benefits invasive alien plants under water variability in a native community

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Journal of Plant Ecology 2019年第3期12卷 574-582页

作者： Duo Chen Hao Xiong Chang-Gen Lin Wei He Zhuo-Wen Zhang Hui wang yong-jian wang Hubei Engineering Technology Research Center for Forestry Information College of Horticulture and Forestry SciencesHuazhong Agricultural UniversityWuhan 430070China

Aims Many invasive alien plant species are clonal and can greatly propa-gate and spread through clonal integration(sharing resources between connected ramets)in heterogeneous and variable ***,we tested whether water variability influences clonal integration of invasive alien plant species and consequently facili-tates their growth and dominance in a native *** We selected four typical invasive clonal plant species in ***(with clonal integration)and disconnected(without clonal integration)clonal fragments were established either under constant watering or variable watering condition in an experimental native plant community consisting of three naturally co-occurring grassland *** part of the container received high nu-trient and distal part received low *** Findings Clonal integration significantly increased biomass,aboveground mass and belowground mass of invasive alien plants in the proximal ramets,the distal ramets and the whole clone and de-creased the growth of native ***,clonal in-tegration significantly increased the growth of invasive plants in variable *** positive effect of clonal integration was stronger in variable watering than in constant *** plants with clonal integration had high biomass proportion(>0.6)in the whole *** results suggest that invasive clonal plants benefit more from clonal integration in variable water en-vironments when established in a native community,and to some extent,clonal integration potentially contribute greatly to the inva-siveness of alien clonal plants when they enter a new community with resource variability.

关键词： biomass proportion nutrient heterogeneity physiological integration plant invasion resource variability

Hydrocarbon gas huff-n-puff optimization of multiple horizontal wells with complex fracture networks in the M unconventional reservoir

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Petroleum Science 2024年第2期21卷 1018-1031页

作者： Hao-Chuan Zhang yong Tang You-Wei He yong Qin jian-Hong Luo Yu Sun Ning wang De-Qiang wang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina CNPC Research Institute of Petroleum Exploration&Development Beijing100083China Southwest Oil&Gas Field Company PetroChinaChengdu610051SichuanChina State Key Laboratory of Offshore Oil Exploitation CNOOC Research Institute Co.LtdBeijing100027China

The oil production of the multi-fractured horizontal wells(MFHWs) declines quickly in unconventional oil reservoirs due to the fast depletion of natural energy. Gas injection has been acknowledged as an effective method to improve oil recovery factor from unconventional oil reservoirs. Hydrocarbon gas huff-n-puff becomes preferable when the CO_(2) source is limited. However, the impact of complex fracture networks and well interference on the EOR performance of multiple MFHWs is still unclear. The optimal gas huff-n-puff parameters are significant for enhancing oil recovery. This work aims to optimize the hydrocarbon gas injection and production parameters for multiple MFHWs with complex fracture networks in unconventional oil reservoirs. Firstly, the numerical model based on unstructured grids is developed to characterize the complex fracture networks and capture the dynamic fracture ***, the PVT phase behavior simulation was carried out to provide the fluid model for numerical simulation. Thirdly, the optimal parameters for hydrocarbon gas huff-n-puff were obtained. Finally, the dominant factors of hydrocarbon gas huff-n-puff under complex fracture networks are obtained by fuzzy mathematical method. Results reveal that the current pressure of hydrocarbon gas injection can achieve miscible displacement. The optimal injection and production parameters are obtained by single-factor analysis to analyze the effect of individual parameter. Gas injection time is the dominant factor of hydrocarbon gas huff-n-puff in unconventional oil reservoirs with complex fracture networks. This work can offer engineers guidance for hydrocarbon gas huff-n-puff of multiple MFHWs considering the complex fracture networks.

关键词： Unconventional oil reservoir Complex fracture network Hydrocarbon gas huff-n-puff Parameter optimization Numerical simulation