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Level density of odd-A nuclei at saddle point

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Nuclear Science and Techniques 2023年第8期34卷 164-173页

作者： Wei Zhang Wei Gao gui-tao Zhang Zhi-Yuan Li School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China

Based on the covariant density functional theory,by employing the core–quasiparticle coupling(CQC)model,the nuclear level density of odd-A nuclei at the saddle point is *** total level density is calculated via the convolution of the intrinsic level density and the collective level *** intrinsic level densities are obtained in the finite-temperature covariant density functional theory,which takes into account the nuclear deformation and pairing *** saddle points on the free energy surface in the(β_(2),γ)plane,the entropy and the associated intrinsic level density are compared with those of the global *** introducing a quasiparticle to the two neighboring even–even core nuclei,whose properties are determined by the five-dimensional collective Hamiltonian model,the collective levels of the odd-A nuclei are obtained via the CQC *** total level densities of the^(234-240)U agree well with the available experimental data and Hilaire’s ***,the ratio of the total level densities at the saddle points to those at the global minima and the ratio of the total level densities to the intrinsic level densities are discussed separately.

关键词： Level density Covariant density functional theory Core–quasiparticle coupling model Saddle point

Modeling and Analysis of Scheduling for Distributed Real-time Embedded Systems

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International Journal of Automation and computing 2010年第4期7卷 525-530页

作者： Hai-tao Zhang gui-Fang Wu Electronic and Information Engineering College Henan University of Science and Technology Luoyang 471003 PRC

Aimed at the deficiencies of resources based time Petri nets （RBTPN） in doing scheduling analysis for distributed real-time embedded systems, the assemblage condition of complex scheduling sequences is presented to easily compute scheduling length and simplify scheduling analysis. Based on this, a new hierarchical RBTPN model is proposed. The model introduces the definition of transition border set, and represents it as an abstract transition. The abstract transition possesses all resources of the set, and has the highest priority of each resource; the cxecution time of abstract transition is the longest time of all possible scheduling sequences. According to the characteristics and assemblage condition of RBTPN, the refinement conditions of transition border set are given, and the conditions ensure the correction of scheduling analysis. As a result, it is easy for us to understand the scheduling model and perform scheduling analysis.

关键词： Embedded systems modeling time Petri nets scheduling analysis

Influence of Aspect Ratio on Rolling Shear Properties of Fast-Grown Small Diameter Eucalyptus Lumber

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Journal of Renewable Materials 2020年第9期8卷 1053-1066页

作者： tao gui Shichen Cai Zhiqiang Wang Jianhui Zhou College of Materials Science and Engineering Nanjing Forestry UniversityNanjing210037China Integrated Wood Engineering University of Northern British ColumbiaPrince GeorgeV2L 1R7Canada

Eucalyptus is a major fast-grown species in South China,which has the potential for producing structural wood products such as cross-laminated timber(CLT).Aspect ratio(board width *** thickness)of eucalyptus lumbers is small due to the small diameter of fast-grown eucalyptus *** evaluate its rolling shear modulus and strength for potential CLT applications,three-layer hybrid CLT shear block specimens with different aspect ratios(2,4,6),were tested by planar shear test *** image correlation(DIC)was employed to measure the rolling shear strain distribution and development during the planar shear *** mean values of rolling shear modulus and strength of eucalyptus lamination were 260.3%and 88.2%higher than those of SPF(Spruce-pine-fir)lamination with the same aspect ratio of 4,*** rolling shear properties of eucalyptus laminations increased as the aspect ratio *** ratio had a significant influence on rolling shear modulus compared to rolling shear *** high shear strain regions were primarily found around the gaps between segments of cross *** quantity of high shear strain regions increased as the aspect ratio of lamination *** high shear strain regions also occurred around the pith and along the glue *** sudden failure of specimen occurred in the high strain *** conclusion,the rolling shear strength and modulus of fast-grown eucalyptus laminations exceed the respective characteristic values for softwoods in the current standard by roughly factors of 3 and 8,indicating great potential for fast-grown eucalyptus wood cross-layers in CLT.

关键词： Fast-grown eucalyptus cross-laminated timber rolling shear aspect ratio digital image correlation

Bisperylene Bisimide Based Conjugated Polymer as Electron Acceptor for Polymer-Polymer Solar Cells

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Chinese Journal of Polymer Science 2017年第2期35卷 239-248页

作者： fan yang 李诚 gui-tao feng xu-dong jiang an-dong zhang 李韦伟 Beijing National Laboratory for Molecular Sciences Chinese Academy of Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

Perylene bisimide （PBI） unit has been widely used to design conjugated materials, which can be used as electron acceptor in organic solar ceils due to its strong electron-deficient ability. In this work, a conjugated polymer based on PBI dimer as monomer was designed, synthesized, and compared to the conjugated polymer containing single PBI as repeating units. The two conjugated polymers were found to have similar molecular weight, absorption spectra and energy levels. Density functional theory calculation revealed that the PBI dimer-based polymer exhibited highly twisted conjugated backbone due to the large dihedral angle between the two PBI units. The PBI-based polymers as electron acceptor were applied into polymer-polymer solar cells, in which PBI dimer-based polymer solar cells were found to show a high short circuit current density （Jsc = 11.2 ***-2） and a high power conversion efficiency （PCE） of 4.5%. In comparison, the solar cells based on PBI-based polymer acceptor only provided a dsc of 7.2 ***-2 and PCE of 2.5%. The significantly enhanced PCE in PBI dimer-based solar cells was attributed to the mixed phase in blended thin films, as revealed by atom force microscopy. This study demonstrates that PB! dimer can be used to design polymer acceptors for high performance polymer- polymer solar cells.

关键词： Polymer solar cells Conjugated polymers Electron acceptor Perylene bisimide

Growth factors induce the improved cardiac remodeling in autologous mesenchymal stem cell-implanted failing rat hearts

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第4期11卷 238-248页

作者： Ze-wei tao Long-gui LI Zhao-hua GENG tao DANG Shan-jun ZHU Department of Cardiovascular Diseases Xinqiao Hospital Third Military Medical University Chongqing 40003 7 China

Therapeutically delivered mesenchymal stem cells (MSCs) improve ventricular remodeling. However,the mechanism underlying MSC cardiac remodeling has not been clearly determined. Congestive heart failure (CHF) was induced in rats by cauterization of the left ventricular free wall. MSCs were cultured from autologous bone marrow and injected into the border zone and the remote myocardium 5 d after injury. Ten weeks later,when compared with sham operation,CHF significantly increased nucleus mitotic index,capillary density,and expression of insulin-like growth factor 1,hepatocyte growth factor and vascular endothelial growth factor in the border zone (P<0.01) and decreased each of them in the remote myocardium (P<0.05 or P<0.01). MSC implantation in CHF dramatically elevated ex-pression of these growth factors in the remote myocardium and further elevated their expression in the border zone when compared with CHF without MSC addition (P<0.05 or P<0.01). This was paralleled by a higher nucleus mitotic index and a significantly increased capillary density both in the remote myocardium and in the border zone,and by a lower percentage of area of collagen and a higher percentage of area of myocardium in the border zone (P<0.05 or P<0.01),and cardiac remodeling markedly improved. Autologous MSC implantation promoted expression of growth factors in rat failing myocardium,which might enhance cardiomyogenesis and angiogenesis,and improved cardiac remodeling.

关键词： Mesenchymal stem cells Growth factor Myocardium Cardiac remodeling

Implicit discourse relation detection using concatenated word embeddings and a gated relevance network

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Science China(Information Sciences) 2019年第11期62卷 195-197页

作者： Jinlan FU Qi ZHANG Jifan CHEN Minlong PENG tao gui Xipeng QIU Xuanjing HUANG Shanghai Key Laboratory of Data Science School of Computer Science Fudan University

Dear editor,Discourse relation detection involves recognizing the relationships between pairs of discourse fragments (e.g., clauses or sentences). As compared with explicit detection, implicit discourse relation detec... 详细信息

关键词： Implicit discourse relation detection using concatenated word embeddings and a gated relevance network

Synthesis and densification of zirconium diboride prepared by carbothermal reduction

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Rare Metals 2018年第12期37卷 1076-1081页

作者： tao gui Xing-Ming Wang Lei Yang Yu-Yang Liu Xue Bai Li-Jun Wang Bo Song Division of Metallurgy and Materials for Rare Metals General Research Institute for Nonferrous Metals School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

Using boron powder as additive, the preparation of zirconium diboride(ZrB 2) by carbothermal reduction was investigated. The results show that the carbothermal reduction cannot be completely done until the temperature is more than 1900 ℃. The ZrB2 particles prepared without boron(B) additive at 1900 ℃ for 3 h are rodlike and show a preferential grain growth along [001] direction. B additive changes the heat effect of the raw materials. With B additive, the morphology of ZrB2 particles turns to be regular shape. The average particle size is about 3.6 μm with 2.5 wt% B additives. With more B additive, the shape of particles turns to be round like and the average particle size is decreased to 2.3 μm when 5 wt% B is added. The existence of oxides in grain boundary is a key factor to keep ZrB2 ceramic from deep densification. Using ZrB2 powder prepared with 5 wt% B additives, by controlling carbon content in ZrB2 powder, ZrB2 ceramic with 93%relative density is hot-pressed.

关键词： Zirconium diboride Carbothermal reduction Grain growth Morphology control Deep densification

Unconditional and Conditional QTL Mapping for Tiller Numbers at Various Stages with Single Segment Substitution Lines in Rice(Oryza sativa L.)

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Agricultural Sciences in China 2008年第3期7卷 257-265页

作者： ZHAO Fang-ming LIU gui-fu ZHU Hai-tao DING Xiao-hua ZENG Rui-zhen ZHANG Ze-min LI Wen-tao ZHANG gui-quan Guangdong Key Laboratory of Plant Molecular Breeding South China Agricultural University Guangzhou 510642 P.R.China

Tiller is one of the most important agronomic traits which influences quantity and quality of effective panicles and finally influences yield in rice. It is important to understand ＂static＂ and ＂dynamic＂ information of the QTLs for tillers in rice. This work was the first time to simultaneously map unconditional and conditional QTLs for tiller numbers at various stages by using single segment substitution lines in rice. Fourteen QTLs for tiller number, distributing on the corresponding substitution segments of chromosomes 1, 2, 3, 4, 6, 7 and 8 were detected. Both the number and the effect of the QTLs for tiller number were various at different stages, from 6 to 9 in the number and from 1.49 to 3.49 in the effect, respectively. Tiller number QTLs expressed in a time order, mainly detected at three stages of 0-7 d, 14-21 d and 35-42 d after transplanting with 6 positive, 9 random and 6 negative expressing QTLs, respectively. Each of the QTLs expressed one time at least during the whole duration of rice. The tiller number at a specific stage was determined by sum of QTL effects estimated by the unconditional method, while the increasing or decreasing number in a given time interval was controlled by the total of QTL effects estimated by the conditional method. These results demonstrated that it is highly effective and accurate for mapping of the QTLs by using single segment substitution lines and the conditional analysis methodology.

关键词： single segment substitution line unconditional QTL mapping conditional QTL mapping tiller number rice

Effect of coarse TiN inclusions and microstructure on impact toughness fluctuation in Ti micro-alloyed steel

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Journal of Iron and Steel Research International 2018年第10期25卷 1043-1053页

作者： tao Liu Mu-jun Long Deng-fu Chen Hua-mei Duan Lin-tao gui Sheng Yu Jun-sheng Cao Hua-biao Chen He-lin Fan State Key Laboratory of Coal Mine Disaster Dynamics and Control College of Materials Science and Engineering Chongqing University Chongqing 400044 China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing University Chongqing 400044 China

Toughness is an important property for steels used in engineering applications. However, recent toughness testing has shown the existence of a significant fluctuation in toughness in a single rolled plate of titanium micro-alloyed steel. The underlying causes of this fluctuation were investigated by fractography, analysis of microstructure and measurement of inclusions. Coarse and distributed TiN inclusions were responsible for the toughness variation, as they tended to act as the potential cleavage initiators to form micro-cracks. From a calculation of the local fracture stress, the critical size of coarse TiN inclusions for dominating micro-crack propagation was 4.93 μm, and similarly that of ferrite grains was 36.6μm. Under current casting and thermo-mechanically controlled processing schedules, the toughness fluctuation of rolled steel plates can be primarily attributed to the fraction of coarse TiN inclusions larger than 5μm. A corresponding relationship between impact energy and the proportion of coarse TiN inclusions was established. Finally, a normalizing treatment was applied to refine the ferrite grains of rolled steel plates. Despite the presence of coarse TiN inclusions, this refinement in ferrite grains minimized the toughness fluctuation and improved the uniformity of the impact properties of the steel plates.

关键词： Impact toughness fluctuation Ti micro-alloyed steel Cleavage fracture Coarse TiN inclusion Grain refinement