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Species recognition and the divergences in the chemical and ultrasonic signals between two coexisting Rattus species

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Current Zoology 2024年第4期70卷 531-538页

作者： Wei-Chao Wang zhi-ming li Yi Chen Jin-Hua Zhang Jian-Xu Zhang Yao-Hua Zhang The State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAs Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijingChina

The ability to recognize and differentiate between conspecifics and heterospecifics as well as their signals is critical for the coexistence of closely related *** the genus Rattus,species are morphologically similar and multiple species often ***,we investigated the interspecific recognition and signal differentiation of two sympatric rat species,the brown rat(Rattus norvegicus,RN)and the Asian house rat(Rattus tanezumi,RT).In a two-way choice test,both RN and RT females showed a preference for conspecific male rats to heterospecific *** females showed a significant preference for accessible urine of males of same species to those of other species,but not for the inaccessi-ble *** the other hand,there were significant differences in the structural characteristics of the ultrasonic vocalization emitted by males of these two rat *** dodecyl sulphate-polyacrylamide gel electrophoresis(SDS-PAGE)and isoelectric focusing electrophoresis unveiled that major urinary proteins(MUPs)in voided urine were more highly expressed in RN males versus RT *** interspecific dif-ferences of urinary volatile compounds were also *** conclusion,female rats had the ability to distinguish between males of either species.

关键词： Asian house rats brown rats closely related species pheromones ultrasonic vocalization.

Hot Deformation and Corrosion Resistance of High-Strength Low-Alloy Steel

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Acta Metallurgica Sinica(English Letters) 2019年第4期32卷 495-505页

作者： Wilasinee Kingkam Cheng-zhi Zhao Hong li He-Xin Zhang zhi-ming li College of Materials Science and Chemical Engineering Harbin Engineering University Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationHarbin Engineering University College of Power and Energy Engineering Harbin Engineering University

The hot deformation characteristics and the corrosion behavior of a high-strength low-alloy(HSLA) steel were investigated at deformation temperatures ranging from 800 to 1100 ℃ and strain rates ranging from 0.1 to 10 s-1 using an MMS-200 thermal simulation testing machine. Based on the flow curves from the experiment, the effects of temperature and strain rate on the dynamic recrystallization behavior were analyzed. The flow stress decreased with increasing deformation temperature and decreasing strain rate. With the assistance of the process parameters, constitutive equations were used to obtain the activation energy and hot working equation. The hot deformation activation energy of HSLA steel in this work was 351.87 kJ/mol. The work hardening rate was used to determine the critical stress(strain) or the peak stress(strain). The dependence of these characteristic values on the Zener-Hollomon parameter was found. A dynamic recrystallization kinetics model of the tested HSLA steel was constructed, and the validity of the model was confirmed by the experimental results. Observation of the microstructures indicated that the grain size increased with increasing deformation temperature,which led to a lowered corrosion resistance of the specimens.

关键词： Dynamic recrystallization Potentiodynamic polarization Hot deformation Flow stress High-strength low-alloy steel

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

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

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