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Chinese Journal of Structural Chemistry 2007年第8期26卷 929-932页

作者： ZHOU Hui DU Shao-wu li zhi-Hua State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

The organic-inorganic hybrid polymer [Mn（mbbimb）2（1,5-nds）]n 1 has been synthesized using 1,5-naphthalenedisulfonate （1,5-nds） and 1,3-bis（benzimidazol-1-ylmethyl）- 2,4,structure analysis indicates that 1 crystallizes in monoclinic, space group C2/c with a=21.3546（17）, b=11.8841（7）, c=22.1588（16）A, β=108.058（3）°, C60H54MnN8O6S2, Mr=1102.17, Z=4, V=5346.5（7）A^3, Dc=1.369 g/cm^3, μ=0.386 mm^-1, F（000）=2300, S=1.091, R=0.0634 and wR=0.1559 for 4641 observed reflections （I 〉 2σ（I））. The Mn center is six-coordinated to furnish a distorted octahedral geometry, and the overall framework is a 6-connected 3D net.

关键词： solvothermal reaction organic-inorganic polymer 6-connected 3D net manganese complex

Modeling natural convection heat transfer from perforated plates

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第5期13卷 353-360页

作者： Zan wu Wei li zhi-jian SUN Rong-hua HONG Department of Energy Engineering Zhejiang University Hangzhou 310027 China

Staggered pattern perforations are introduced to isolated isothermal plates,vertical parallel isothermal plates,and vertical rectangular isothermal fins under natural convection *** performance of perforations was evaluated theoretically based on existing correlations by considering effects of ratios of open area,inclined angles,and other geometric *** was found that staggered pattern perforations can increase the total heat transfer rate for isolated isothermal plates and vertical parallel plates,with low ratios of plate height to wall-to-wall spacing(H/s),by a factor of 1.07 to 1.21,while only by a factor of 1.03 to 1.07 for vertical rectangular isothermal fins,and the magnitude of enhancement is proportional to the ratio of open ***,staggered pattern perforations are detrimental to heat transfer enhancement of vertical parallel plates with large H/s ratios.

关键词： Staggered pattern perforation Natural convection Inclined plate Parallel plate Rectangular fins

Energy dissipation and contour integral characterizing fracture behavior of incremental plasticity

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Acta Mechanica Sinica 2011年第2期27卷 251-258页

作者： Qi-lin He lin-zhi wu Ming li Hong-Bo Chen Chen Center for Composite Materials Harbin Institute of Technology 150080 Harbin China

J ep -integral is derived for characterizing the frac- ture behavior of elastic-plastic materials. The J ep -integral differs from Rice’s J-integral in that the free energy density rather than the stress working density is employed to define energy-momentum tensor. The J ep -integral is proved to be path-dependent regardless of incremental plasticity and deformation plasticity. The J epintegral possesses clearly clear physical meaning：（1） the value J ep tip evaluated on the infinitely small contour surrounding the crack tip represents the crack tip energy dissipation; （2） when the global steadystate crack growth condition is approached, the value of J ep farss calculated along the boundary contour equals to the sum of crack tip dissipation and bulk dissipation of plastic zone. The theoretical results are verified by simulating mode I crack problems.

关键词： J-integral · Energy dissipation · Proportional loading · Deformation plasticity · Incremental plasticity

Comparisons of nozzle orifice processing methods using synchrotron X-ray micro-tomography

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第3期13卷 182-188页

作者： zhi-jun wu zhi-long li Wei-di HUANG Hui-feng GONG Ya GAO Jun DENG Zong-jie HU School of Automotive Studies Tongji University Shanghai 201019 China

Based on the high flux synchrotron X-ray of the Shanghai Synchrotron Radiation Facility (SSRF), high precision 3D digital models of diesel nozzle tips have been established by X-ray micro-tomography technology, which reveal the internal surfaces and structures of orifices. To analyze the machining precision and characteristics of orifice processing methods, an ap- proach is presented based on the parameters of the internal structures of nozzle orifices, including the nozzle diameter, the orifice inner surface waviness, the eccentricity distance and the angle between orifices. Using this approach, two kinds of nozzle orifice processing methods, computerized numerical control drilling and electric discharge machining, have been studied and compared. The results show that this approach enables a simple, direct, and comprehensive contrastive analysis of nozzle orifice processing methods. When processing a single orifice, the electric discharge machining method has obvious advantages. However, when there are multiple orifices, the error levels of the two methods are similar in relation to the symmetry of distribution of the orifices.

关键词： Diesel nozzle Internal structures Orifice processing methods Synchrotron X-ray micro-tomography

Analysis of a FBG sensing system with transverse uniform press by using genetic algorithm

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Optoelectronics Letters 2008年第2期4卷 121-125页

作者： TENG Feng-cheng YIN Wen-wen wu Fei li zhi-quang wu Ti-hua Institute of Automatic Instrument College of Electric Engineering Yanshan University Qinhuangdao 066004 China

An analytical method in a quasi-static fiber grating sensing system under transverse uniform press is proposed based on genetic algorithm The effect of population size, generations, crossover ratio and mutation ratio to genetic algorithm, and the optimization parameters of genetic algorithm were given. The relevant experimental system is constructed. The simulation and experiments show that the analytical method proposed can be applied to analyze the reflective spectra of the quasistatic FBG sensing system at transverse uniform press, the strain measurement with high-precision of 0.91% can be realized

关键词： FBG 感觉系统遗传算法光纤元件

Predicting Critical Conditions and Stress-Strain Curves for Dynamic Recrystallization in SPHC Steel

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Journal of Iron and Steel Research International 2010年第7期17卷 51-57页

作者： wu Lai-zhi li Xue-song CHEN Jun ZHANG Hong-bing CUI Zhen-shan Department of Plasticity Technology Shanghai Jiaotong University Shanghai 200030 China

The hot compression tests on an SPHC steel were carried out in the temperature range of 900-1150 ℃ and strain rate range of 0.1-10 s-1,in which the maximum true strain is *** activation energy of test steel was calculated,to be 299.4 kJ/*** critical stresses and strains for initiation of dynamic recrystallization were determined based on changes of the work hardening rate（θ）as a function of the flow stress（σ）or strain（ε）,*** dependence of the peak strain（εp）,the peak stress（σp）,and the steady state stress（σs）were determined based on the Zener-Hollomen *** mathematical models of the flow stress evolution were established in the hardening and dynamic recovery region and dynamic recrystallization region,*** average error between experimental curves and predicted ones was around 3.26%.

关键词： flow stress dynamic recrystallization critical stress critical strain SPHC steel

Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW China: Implications for the Ediacaran microbial mound construction and hydrocarbon exploration

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Petroleum Science 2024年第2期21卷 806-822页

作者： Jin-Min Song Xin Jin Zhong Luo Shu-Gen liu Shao-Bo liu Xing-zhi Ma zhi-wu li Xue-Song Lu ling-li Zhao Ke-Ran li Jia-Xin Ren li-Zhou Tian Hao-Shuang Deng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanChina PetroChina Research Institute of Petroleum Exploration and Development Beijing100083China Xihua University Chengdu610039SichuanChina

Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain late

关键词： Sichuan Basin The Member Deng-2 Marginal microbial mound-bank complex Depositional model Exploration implications

New phenylbutenoids and terpene glycosides from Ginkgo biloba leaves

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Chinese Journal of Natural Medicines 2024年第2期22卷 161-170页

作者： SUN Zeshi liN Shan wu zhi-li DONG Hong-Yuan XU Xi-Ke li Hui-liang WANG Jinxin School of Pharmacy Second Military Medical UniversityShanghai 200433China State Key Laboratory of New Drug and Pharmaceutical Process Shanghai Institute of Pharmaceutical IndustryChina State Institute of Pharmaceutical IndustryShanghai 201203China

Our continued works on the chemical constituents of Ginkgo biloba(***)leaves has led to the isolation of two novel phenylbutenoids(1,2),along with five previously unidentified terpene glycosides(3−7).Among them,compounds 1 and 2 represent unique(Z)-phenylbutenoids,3−6 are megastigmane glycosides,and 7 is identified as a rare bilobanone glycoside(Fig.1).This study marks the first reported isolation of phenylbutenoid and bilobanone glycoside from *** chemical structures of these compounds were elucidated through extensive spectroscopic analysis,including HR-ESI-MS and various 1D and 2D NMR ***,the absolute configurations of these molecules were determined using Mosher’s method,ECD experiments,and Cu-KαX-ray crystallographic analyses.

关键词： Ginkgo biloba Phenylbutenoid Megastigmane glycoside Bilobanone glycoside

Effect of Cryogenic Treatment on Properties of Cr8-Type Cold Work Die Steel

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Journal of Iron and Steel Research International 2010年第6期17卷 43-46,59页

作者： CHI Hong-xiao MA Dang-shen YONG Qi-long wu li-zhi ZHANG Zhan-pu WANG Yong-wei Faculty of Materials Science and Engineering Kunming University of Science and Technology Kunming 650093 Yunnan China Institute for Structural Materials Central Iron and Steel Research Institute Beijing 100081 China Heye Special Steel Co Ltd Shijiazhuang 050031 Hebei China

The effect of cryogenic treatment on the properties of Cr8-type cold work die steel was investigated. The results show that cryogenic treatment increases hardness by decreasing retained austenite, but the degree depends on the austenitizing temperature. When quenching at lower austenitizing temperature, the steel can obtain higher tough- ness by cryogenic treatment substituting conventional treatment process. Cryogenic time has little effect on cryogenic treatment. Conversely, cryogenic temperature has a great effect on cryogenic treatment and the effect of cryogenic treatment is more obvious with decreasing cryogenic temperature. In addition, deep cryogenic treatment improves the wear resistance by precipitating more homogeneous specific carbides.

关键词： cryogenic treatment tool steel cold work die steel property wear resistance

“One stone, two birds”: Salt template enabling porosity engineering and single metal atom coordinating toward high-performance zinc-ion capacitors

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Journal of Energy Chemistry 2025年第1期100卷 637-645页

作者： Chunliu Zhu Huanyu liang Ping li Chenglong Qiu Jingyi wu Jingwei Chen Weiqian Tian Yue Zhu zhi li Huanlei Wang School of Materials Science and Engineering Ocean University of China Department of Chemical and Materials Engineering University of Alberta

Zinc-ion hybrid capacitors （ZIHCs） have received increasing attention as energy storage devices owing to their low cost,high safety,and environmental ***,their progress has been hampered by low energy and power density,as well as unsatisfactory long-cycle stability,mainly due to the lack of suitable electrode *** this context,we have developed manganese single atoms implanted in nitrogen-doped porous carbon nanosheets （MnSAs/NCNs） using a metal salt template method as cathodes for *** metal salt serves a dual purpose in the synthesis process:It facilitates the uniform dispersion of Mn atoms within the carbon matrix and acts as an activating agent to create the porous *** applied in ZIHCs,the MnSAs/NCNs electrode demonstrates exceptional performance,including a high capacity of 203 m Ah g-1,an energy density of 138 Wh kg-1at 68 W kg-1,and excellent cycle stability with 91%retention over 10,000 *** calculations indicate that the introduced Mn atoms modulate the local charge distribution of carbon materials,thereby improving the electrochemical *** work demonstrates the significant potential of carbon materials with metal atoms in zinc-ion hybrid capacitors,not only in enhancing electrochemical performance but also in providing new insights and methods for developing high-performance energy storage devices.

关键词： Zinc ion hybrid capacitors Cathodes Carbon materials Heteroatoms Single atoms