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Quantum McKay Correspondence for Disc Invariants of Toric Calabi–Yau 3-orbifolds

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Acta Mathematica Sinica,English Series 2015年第1期31卷 29-34页

作者： Hua-zhong KE Jian zhou Department of Mathematical Sciences Tsinghua University

We announce a result on quantum McKay correspondence for disc invariants of outer legs in toric Calabi-Yau 3-orbifolds, and illustrate our method in a special example [C^3/Z5（1, 1, 3）].

关键词： Quantum McKay correspondence disc invariants open mirror symmetry

Better Choice:Linear Long Chains Rather than Branched Ones to Improve Mechanical Performance of Polyethylene through Generating Shish-Kebabs

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Chinese Journal of Polymer Science 2020年第7期38卷 715-729,I0006页

作者： Lu-Feng Deng Xi-Xi Zhang dong zhou Jian-Hua Tang Jun Lei Jun-Fang Li zhong-Ming Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China College of Chemical Engineering Sichuan UniversityChengdu 610065China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

We utilized two structurally different long chains(linear and branched ultra-high molecular weight polyethylene)to reveal the dependence of flow-induced crystallization on long chain architecture,and prepared two bi-disperse systems of 98 wt%short chain and 2 wt%long chain.A flow field was applied to the bi-disperse polyethylene melt by a modified injection-molding machine,known as oscillation shear injection molding(OSIM).For the first time,the structural influence of long chains on flow-induced shish-kebab formation was systematically *** the intermediate layer of OSIM samples,the branched long chains were better than the linear long chains at inducing shish-kebab formation,agreeing with the reported literatures,because the branches can maintain their oriented conformations *** unexpectedly,the reverse is the case for the core layer of OSIM samples,where the shear flow was much weaker than the intermediate *** understand the unexpected phenomenon,the lifetime of shishes induced by different long chains was *** demonstrated that the linear-induced shishes possessed higher thermal stability than the branched-induced ones so that the linear-induced shishes could survive in the core layer of OSIM ***,unlike other methods for flow-induced crystallization,OSIM could create samples for measuring mechanical properties,and thus offer the chance to reveal the relationship between structure and *** mechanical results demonstrated that both long chains remarkably enhanced the mechanical properties because of the significant promoting effect of long chains and intense flow fields on shish-kebab ***,the linear long chains induced more stable and flawless shishes with higher tensile strength and modulus(80.4 and 1613.5 Mpa,respectively)than the branched ones(74.4 and 1489.3 Mpa).Our research not only helps elucidate the mechanism of shish-kebab formation but also provides a better choice to reinforce

关键词： Polyethylene Crystallization Shear-induced Long chain Short chain

Control of cotton pests and diseases by intercropping:A review

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Journal of Integrative Agriculture 2021年第12期20卷 3089-3100页

作者： CHI Bao-jie ZHANG dong-mei dong He-zhong Cotton Research Center Shandong Academy of Agricultural SciencesJinan 250100P.R.China College of Life Sciences Shandong Normal UniversityJinan 250014P.R.China College of Agronomy Hebei Agricultural UniversityBaoding 071000P.R.China

Cotton(Gossypium hirsutum L.)is a globally important crop that is often damaged by pests and *** cotton pests and diseases management is dependent on chemical *** chemical pesticides are usually effective,long-term application of these pesticides often leads to increased insecticide resistance in the pests,fewer natural enemies,reduced natural control,and a degraded *** of increased environmental awareness and the need for sustainable cotton production,the control of cotton pests and diseases using biological means like intercropping is increasingly receiving *** of cotton with other crops can often boost the total yield and output of the intercropping system and provide significant economic benefits without sacrificing cotton *** also increases the number of natural enemies,and reduces the occurrence of cotton pests and diseases by altering the ecological structure and environmental conditions in the ***-based intercropping is an effective strategy to reduce the competition between cotton and grain or other economic crops for arable *** is also an important way to increase the populations of natural enemies in cotton fields for the management of pests and ***,inappropriate intercropping can also increase labor requirements and even result in inadequate control of pests and *** review focuses on the performance and the mechanisms of intercropping for reducing cotton pests and disease as well as on the effective management of intercropping *** risks and limitations,as well as the study approaches needed and the prospects of intercropping for the control of cotton pests and diseases,are also *** information is intended to aid researchers and growers in designing economically viable and ecologically friendly pest and disease management strategies that will reduce the use of chemicals and the cost of cotton production.

关键词： cotton-based intercropping pest management risk and limitation

Efficient hydrolysis of hemicellulose to furfural by novel superacid SO_4H-functionalized ionic liquids

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Green Energy & Environment 2019年第1期4卷 49-55页

作者： Wei Hui Yan zhou Yan dong Zhi-Jun Cao Fei-Qiang He Min-zhong Cai Duan-Jian Tao College of Chemistry and Chemical Engineering Institute of Advanced Materials Jiangxi Normal University

Novel superacid SO_4H-functionalized ionic liquids(SFILs) were designed and prepared in this work. The catalytic activities of SFILs were evaluated in xylan hydrolysis and xylose dehydration to produce furfural. Combined with the results of acid strength of SFILs characterized by solid-state ^(31)P MAS NMR, it was found that the catalytic performance of SFILs was positively correlated to their acid strength. The superacid SFIL [Ch-SO_4H][CF_3SO_3] displayed the best catalytic performance with more than 80% yield of furfural, and it was also obviously superior to usual SO_3H-functionalized acidic ILs, mineral liquid acids, and acidic resin Amberlyst-15 catalysts in catalytic activity under optimized conditions. In addition, the superacid SFIL [Ch-SO_4H][CF_3SO_3] could be easily separated from reaction system and reused at least five times without obvious decrease.

关键词： Superacid Ionic liquids Hemicellulose Hydrolysis Furfural

A novel method for gamma spectrum analysis of low-level and intermediate-level radioactive waste

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Nuclear Science and Techniques 2023年第6期34卷 199-213页

作者： Hui Yang Xin-Yu Zhang Wei-Guo Gu Bing dong Xue-Zhi Jiang Wen-Tao zhou De-zhong Wang School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai200240China

The uncertainty of nuclide libraries in the analysis of the gamma spectra of low-and intermediate-level radioactive waste(LILW)using existing methods produces unstable *** address this problem,a novel spectral analysis method is proposed in this *** this method,overlapping peaks are located using a continuous wavelet *** improved quadratic convolution method is proposed to calculate the widths of the peaks and establish a fourth-order filter model to estimate the Compton edge baseline with the overlapping *** with the adaptive sensitive nonlinear iterative peak,this method can effectively subtracts the ***,a function describing the peak shape as a filter is used to deconvolve the energy spectrum to achieve accurate qualitative and quantitative analyses of the nuclide without the aid of a nuclide *** spectrum acquisition experiments for standard point sources of Cs-137 and Eu-152,a segmented gamma scanning experiment for a 200 L standard drum,and a Monte Carlo simulation experiment for triple overlapping peaks using the closest energy of three typical LILW nuclides(Sb-125,Sb-124,and Cs-134)are *** results of the experiments indicate that(1)the novel method and gamma vision(GV)with an accurate nuclide library have the same spectral analysis capability,and the peak area calculation error is less than 4%;(2)compared with the GV,the analysis results of the novel method are more stable;(3)the novel method can be applied to the activity measurement of LILW,and the error of the activity reconstruction at the equivalent radius is 2.4%;and(4)The proposed novel method can quantitatively analyze all nuclides in LILW without a nuclide *** novel method can improve the accuracy and precision of LILW measurements,provide key technical support for the reasonable disposal of LILW,and ensure the safety of humans and the environment.

关键词： HPGe detector Low-level and intermediate-level radioactive waste Gamma spectrum analysis method Deconvolution method Continuous wavelet transform

Effect of electropulsing on austenite to ferrite transformation in low-carbon steel

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Journal of Iron and Steel Research International 2021年第4期28卷 437-444页

作者： Zheng-hai Zhu Li zhou Fei He Xiao-fang Shi Li-zhong Chang Hai-jun Wang Hong-biao dong School of Metallurgic Engineering Anhui University of TechnologyMaanshan 243002AnhuiChina School of Engineering University of LeicesterLeicester LE17RHUK

We explore the application of electropulsing for the control of phase transformation in a low-carbon *** effect of electropulsing on the transformation from austenite to ferrite in continuous casting low-carbon steel slab has been studied through experimental and thermodynamic *** results reveal that electropulsing promotes the precipitation of ferrite within austenite grain in the low-carbon *** the electropulsing intensity increases,the precipitation of ferrite increases within austenite grains,and ferrite omentum precipitates become thinner along the austenite grain *** results provide a basis for controlling the austenite to ferrite transformation in low-carbon steel.

关键词： Electropulsing Austenite Ferrite Transformation Nucleation Low-carbon steel

B位掺杂提升CsSnI_(3)钙钛矿结构和电荷稳定性的第一性原理研究

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原子与分子物理学报 2025年第6期42卷 144-152页

作者：赵思健葛治中杨旭东上海交通大学材料科学与工程学院上海200240

全无机CsSnI_(3)钙钛矿拥有理想的带隙宽度(1.3 eV),光电转化效率理论峰值达到33%.目前CsSnI_(3)太阳能电池的发展受制于的CsSnI_(3)的结构不稳定性和Sn^(2+)易被氧化为Sn^(4+)的问题.研究基于第一性原理,详细探讨了一系列金属元素对CsS... 详细信息

全无机CsSnI_(3)钙钛矿拥有理想的带隙宽度(1.3 eV),光电转化效率理论峰值达到33%.目前CsSnI_(3)太阳能电池的发展受制于的CsSnI_(3)的结构不稳定性和Sn^(2+)易被氧化为Sn^(4+)的问题.研究基于第一性原理,详细探讨了一系列金属元素对CsSnI_(3)进行B位掺杂改性的方案,旨在提升CsSnI_(3)结构稳定性,并抑制CsSnI_(3)中Sn^(2+)被氧化为Sn^(4+)的问题.计算结果表明,在CsSnI_(3)钙钛矿B位掺杂三价金属Sb、Bi能够阻碍CsSnI_(3)相变生成Cs_(2)SnI_6,并且抑制Sn^(2+)的氧化;尤其在晶格中存在锡空位缺陷时,Sb、Bi掺杂对于Sn^(4+)形成的抑制效果更为显著.同时,低浓度的Sb、Bi掺杂不会改变CsSnI_(3)的直接带隙特性,且带隙宽度变化较小,因此能够在维持CsSnI_(3)优良光电活性的基础上进一步提高结构和电荷的稳定性.研究结果为实现高效且稳定的CsSnI_(3)钙钛矿太阳能电池提供了重要的理论指导.

关键词：全无机锡基钙钛矿第一性原理 B位掺杂相稳定性电子结构

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Some Existence Theorems on Path Factors with Given Properties in Graphs

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Acta Mathematica Sinica,English Series 2020年第8期36卷 917-928页

作者： Si zhong zhou Zhi Ren SUN School of Science Jiangsu University of Science and TechnologyZhenjiang 212003P.R.China School of Mathematical Sciences Nanjing Normal UniversityNanjing 210046P.R.China

A path factor of G is a spanning subgraph of G such that its each component is a path.A path factor is called a P≥n-factor if its each component admits at least n vertices.A graph G is called P≥n-factor covered if G admits a P≥n-factor containing e for any e∈E(G),which is defined by[Discrete Mathematics,309,2067-2076(2009)].We first define the concept of a(P≥n,k)-factor-critical covered graph,namely,a graph G is called(P≥n,k)-factor-critical covered if G-D is P≥n-factor covered for any D⊆V(G)with|D|=*** this paper,we verify that(i)a graph G withκ(G)≥k+1 is(P≥2,k)-factor-critical covered if bind(G)>2+k/3;(ii)a graph G with|V(G)|≥k+3 andκ(G)≥k+1 is(P≥3,k)-factor-critical covered if bind(G)≥4+k/3.

关键词： Graph binding number P≥2-factor P≥3-factor (P≥2,k)-factor-critical covered graph (P≥3,k)-factor-critical covered graph

Morphology and magnetic properties of α-Fe_2O_3 particles prepared by octadecylamine-assisted hydrothermal method

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Particuology 2012年第4期10卷 456-461页

作者： zhong Liu Baoliang Lv dong Wu Yuhan Sun State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China Low Carbon Conversion Center Shanghai Advanced Research InstituteChinese Academy of SdencesShanghai 201203China Graduate University of the Chinese Academy of:Sciences Beijing 100049China

α-Fe2O3 particles with various morphologies, including micro-doublesphere, tetrakaidecahedron and nanoparticles-aggregated micro-ellipsoid, were successfully synthesized via an octadecylamine-assisted hydrothermal method. The products were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and high-resolution transmission electron microscopy （HRTEM）. The results indicate that the presence of octadecylamine played a crucial role in morphology evolution by selective crystal adsorption. The protonated octadecylamine increased the pH value that accelerated nucleation, and the long alkyl groups of octadecylamine acted as an adsorption inhibitor to retard the growth of nanoparticles. The as-prepared α-Fe2O3 particles exhibited higher remanent magnetization and coercivity than other α-Fe2O3 particles of similar size. These properties should be attributed to the superstructure and the shape anisotropy of the synthesized particles.

关键词： Octadecylaminec α-Fe2O3MorphologiesMagnetic property