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Beyond 1,4-addition of in-situ generated(aza-)quinone methides and indole imine methides

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Chinese Chemical Letters 2024年第7期35卷 35-53页

作者： Yan-li li zhi-ming li Kai-Kai Wang Xiao-Long He Medical College Xinxiang UniversityXinxiang 453000China School of Pharmacy Xinxiang UniversityXinxiang 453000China School of Food and Bioengineering Xihua UniversityChengdu 610039China

The conjugate addition of in-situ generated(aza-)quinone methides(QMs)and indole imine methides(IIMs)emerged as a powerful protocol to access densely functionalized benzenes and *** alcohols,aminobenzhydryl alcohols,and varied indolylmethanols served as most effective precursors for the in-situ generation of such reactive species under acid *** relevant propargylic alcohol has proven to be an elegant precursor to generate the propargylic-QMs and-IIMs via the acid promoted dehydration process,thus enabling diverse challenging remote activation to proceed conjugate1,6-and 1,***,the heteroarene has proven to be workable to transfer the LUMO of the p-QMs and 2-IIMs,thus inducing the remote nucleophilic dearomative *** conjugate additions of(aza-)p-QMs and varied IIMs has made significant contribution in the field of remote activation chemistry in past *** review summarizes the latest advances of the remote conjugate additions of the in-situ generated QMs and IIMs.

关键词： Conjugate addition QMs IIMs LUMO Remote activation Dearomative addition

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

Rapid formation of β-allyl substituted isotetronic acid derivatives via Claisen rearrangement using a microfludic device

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Chinese Chemical Letters 2011年第2期22卷 167-170页

作者： Xia Ping Ma zhi ming li Quan Rui Wang Department of Chemistry Fudan University Shanghai 200433 China Received 14 May 2010

The thermal Claisen rearrangement of O-allyl substituted isotetronic acids 1 was successfully carried out within a glass microreactor operated with temperature at 150℃and a flow rate of 1 mL/*** strategy provides an efficient alternative way toβ-allyl substituted isotetronic acid derivatives 2 in high yields with much accelerated reaction speed.

关键词： Microreactor Claisen rearrangement O-Allyl substituted isotetronic acids β-Allyl substituted isotetronic acids

Hydrocarbon generation from lacustrine shales with retained oil during thermal maturation

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Petroleum Science 2020年第6期17卷 1478-1490页

作者： Xin-He Shao Xiong-Qi Pang Mao-Wen li zhi-ming li Yi Zhao State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China College of Geosciences China University of PetroleumBeijing 102249China State Key Laboratory of Shale Oil and Shale Gas Resources and Eff ective Development SINOPEC Petroleum Exploration and Production Research InstituteBeijing 100083China SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms Wuxi Institute of Petroleum GeologyWuxi 214126JiangsuChina

Thermal maturation in the shale oil/gas system is inherently complex due to the competitive interplays between hydrocarbon generation and retention *** study hydrocarbon generation characteristics from shales within different stages of thermal maturation under the influence of retained oil,we performed Micro-Scale Sealed Vessels(MSSV)pyrolysis on a set of artificially matured lacustrine shale s amples from the Shahejie Formation in the Dongpu Depression in Bohai B ay Basin,*** results show that hydrocarbon yields of shale samples with or without retained oil at various thermal maturities follow different evolution *** components(C15+)in samples crack at high temperatures and generally follow a sequence,where they first transform into C6-14 then to C2-5 and *** accounts for most of the gaseous products at high temperatures in all samples,with different *** cracking of C2-5 is the main methane-generating process in samples with retained oil,whereas the source of methane in samples without retained oil is *** the studied shales,retained oils at early-mature stage retard the transformation of liquid to gaseous hydrocarbon and prompt the cracking of C2-5 to C1 to some *** reaction related to gypsum in the studied samples is the primary reason that can explain the loss of hydrocarbon yields,especially at high *** addition,transformation of volatile hydrocarbons to gas and coke also accounts for the loss of generated hydrocarbon,as a secondary factor.

关键词： MSSV pyrolysis Hydrocarbon generation Lacustrine shales Thermal maturation Retained oil

Characterization of Zn-doped GaN grown by metal–organic vapor phase epitaxy

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Rare Metals 2020年第11期39卷 1328-1332页

作者： Cui-Ting Wu Yue Zhou Qiao-Yun Sun Lu-Qiu Huang Ai-Lan li zhi-ming li Information Department Beijing City UniversityBeijing100083China State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of ScienceChangchun130033China State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun130033China

The point defects and photoluminescence(PL)spectra of gallium nitride(GaN)epilayers with Mg,Zn,and unintentional doping were investigated in this *** concentration of point defects(Ga vacancy and its related complexes)in the Zn-doped GaN is consistent with that in the Mg-doped GaN,but lower than that in undoped *** is suggested that Zn(Mg)atoms occupy Ga sites and suppress the formation of Ga *** the blue luminescence(BL)band intensity of GaN:Zn with that of GaN:Mg,a factor of 10 strong PL intensity demonstrates that a moderate incorporation of Zn to GaN is likely to improve the structural quality of *** studies on 2.93 eV BL band for GaN:Zn reveal that the Zn related BL band behaves as a donor-acceptor pairs *** the acceptor level,isolated Zn_(Ga)with the activation energy of 0.386 eV above the valence band is obtained from temperature-dependent PL measurements,whereas the deep donor defect responsible for the 2.93 eV band is deduced to be 164 meV below the conduction *** O_(N)-H complex model is suggested to explain the deep donor origin.

关键词： GaN Metal–organic chemical vapor deposition Zn-doped Photoluminescence Donor–acceptor pairs

Effect of Cr on microstructure and oxidation behavior of TiAl-based alloy with high Nb

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China Foundry 2018年第1期15卷 17-22页

作者： Zhu-Hang Jiang Cheng-zhi Zhao Jiao-Jiao Yu He-Xin Zhang zhi-ming li Key Laboratory of Superlight Materials and Surface Technology College of Materials Science and Chemical Engineering Harbin Engineering University College of Power and Energy Engineering Harbin Engineering University

Three novel multi-microalloying TiAl-based alloys containing high Nb were designed and fabricated Thermogravimetric method was applied to investigate the influence of Cr on the oxidation behavior of high Nb TiAl alloy at 1,073 K for 200 h in laboratory air. The 2 at.% and 4 at.% Cr were added into the alloy,(respectivel named 2 Cr and 4 Cr compared to the Cr-free ternary alloy, 0 Cr alloy). The alloys' microstructure and compositio as well as the composition distribution of the oxidation scale were analyzed by means of Scanning Electro Microscopy(SEM), Energy Dispersive Spectroscopy(EDS), and X-Ray Diffractometry(XRD). The results show that the addition of Cr decreases the grain size of the Nb-TiAl alloy and leads to a transformation from a full lamellar structure to a nearly fully lamellar structure. When oxidized at 1,073 K for 200 h, the oxidized mass gai of the alloy increases with an increase in Cr addition amount in the first 100 h and decreases in the last 100 h With the increase of Cr content, the oxidation surface turns compact but uneven in morphology, which may affec the oxidation resistance of the alloy by increasing the peeling off risk of the oxidation layer at friction conditions.

关键词： TiAl-based alloys microstructure oxidation Cr addition

Simulation of Potential Production and Optimum Population Quantitative Indices for the Second Hybrid Rice

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Agricultural Sciences in China 2006年第7期5卷 498-505页

作者： YAN li-Jiao YAO Zhong ZHENG zhi-ming li Hua-bin Agro-Ecology Institute Life Science College Zhejiang University Hangzhou 310029 P.R.China

The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, daily dry matter accumulation and partitioning, daily CO2 assimilation of the canopy, leaf area, and tiller development. The model preferably simulated the dynamic rice development because of the thorough integration of the effects of temperature and light on the rates of rice development, photosynthesis, respiration, and. other ecophysiological processes. In addition, this model has attainable grain yield in the test experiment that showed the potential yield of cultivar Xieyou 46 ranged from 11 to 13 tons ha-~. Besides, the model was used to optimize the combinations of the transplanting date, seedling age and density for cultivar Xieyou 46 at Jinhua area, and the population quantitative indices to attain the potential yield such as maximum stems, effective panicles, filled grain number/leaf area, and so on. The result showed that the combination of transplanting date on July 25, seedling age of 35 days and base seedling density of 1.33 x 106ha-1 is the optimum combination for the second hybrid rice production in Jinhua County, China. And the maximum stems, the effective panicles, the filled grain per panicle, the peak of optimum LAI, LAI in later filling stage, and the filled grain number/leaf were 6.03×10^6ha, 3.99×10^6ha, 119.2, 8.59, 5-6, and 0.64, respectively.

关键词： simulation model potential production optimum population quantitative indices second hybrid rice

Synthesis and bioactivity of novel coumarin derivatives containing(E)-methyl 2-(methoxyimino)-2-phenylacetates

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Chinese Chemical Letters 2011年第6期22卷 663-666页

作者： Ai Ying Guan Chang ling liu zhi Nian li ming Xing Zhang State Key Laboratory of the Discovery and Development of Novel Pesticide Shenyang Research Institute of Chemical Industry Co.Ltd. Shenyang 110021China

Ten coumarin derivatives containing（E）-methyl 2-（methoxyimino）-2-phenylacetate were synthesized and *** compounds were identified by IR,~1H NMR and elemental *** test results indicated that compound 5j（R^1 is methyl and R^2 is n-C_6H_（13）） was the optimal structure in this paper with good fungicidal activity against CDM（85%） at 6.25 mg/L concentration.

关键词： Coumarins Methoxyacrylates Intermediate derivatization method Fungicides

Effect of coiling and annealing temperatures on yield point behavior of low-carbon steel

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Journal of Iron and Steel Research International 2020年第3期27卷 325-333页

作者： zhi-ming li Xiang li Lei Yang Zheng-yan Shen Bi-lei Wang Shun-li Zhao Gao-fei liang Chang-jiang Song State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200072China Technology Center of Baoshan Iron&Steel Co. Ltd.Shanghai 201900China

Low-carbon steel is widely used for household appliance and automotive panel steel because of its excellent ***,yield point phenomena easily appear in the low-carbon steel produced by a continuous annealing process and cause degradation to the surface quality during *** effect of the coiling temperature(600-750℃)and annealing temperature(740-820℃)on the yield point behavior is *** tests show that coiling temperature has a greater effect on yield point elongation(YPE)and aging index(AI)than the annealing *** observations show that coiling temperature at 750℃would make the micron-sized carbides appearing at the grain boundary disappear and a number of dispersed nanoscale carbides precipitate in grain interior,corresponding to the highest solid solution carbon content in the matrix of 750℃coiled *** experimental results suggest that AI rather than YPE has a positive relationship with the solid solution carbon content of the low-carbon *** YPE has a positive relationship with the upper/lower yield strength.

关键词： Low-carbon steel Carbide Yield point elongation Coiling temperature Annealing temperature