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Surface Electrostatic Potentials of Polychlorinated Dibenzofurans and Their Applications in Quantitative Structure-toxicity Relationships

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Chinese Journal of Structural Chemistry 2005年第4期24卷 407-412页

作者： ZOUJian-wei HUGui-xiang JIANGYong-jun ZENGMin ZHUANGShu-Lin YUQing-Sen KeyLaboratoryforMolecularDesignandNutritionEngineering NingboInstituteofTechnolog3 ZhejiangUniversity Ningbo315104China

Polychlorinated dibenzofurans (PCDFs) represent an important kind of serious pollutant. They are highly toxic and persistent in environment. In this paper, geometrical optimizations and subsequent calculations of electrostatic potentials (ESPs) on molecular surface have been performed for all 135 PCDF congeners at the HF/6-31G* level. The effects of substitution value and variation of substitution position upon the surface ESPs have been discussed. A series of statistic-based structural descriptors derived from the surface ESPs have been calculated. For some PCDF congeners, linear relationships between aryl hydrocarbon receptor (AhR) biding affinity and aryl hydrocarbon hydroxylase (AHH) induction potency as well as theoretical descriptors have been established by multiple linear regression method. It appears that the quantities derived from the surface ESPs, Vs,min, Vs , VS +, σ+ and Nvmin, 2 together with the molecular surface area and the energy gap between HOMO and LUMO can be well used to express the quantitative structure-toxicity relationships of PCDFs.

关键词： QSAR molecular electrostatic potential ab initio polychlorinated dibenzofuran

The Substitution Secant/Finite Difference Method for Large Scale Sparse Unconstrained Optimization

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Acta Mathematicae Applicatae Sinica 2005年第4期21卷 581-596页

作者： Hong-wei Zhang jun-xiang Li Department of Applied Mathematics Dalian University of Technology Dalian 116024 China

This paper studies a substitution secant/finite difference （SSFD） method for solving large scale sparse unconstrained optimization problems. This method is a combination of a secant method and a finite difference method, which depends on a consistent partition of the columns of the lower triangular part of the Hessian matrix. A q-superlinear convergence result and an r-convergence rate estimate show that this method has good local convergence properties. The numerical results show that this method may be competitive with some currently used algorithms.

关键词： Unconstrained optimization substitution Hessian sparsity secant method

Centralized light-wave WDM-PON employing DQPSK downstream and OOK remodulated upstream signals

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 125-128页

作者： ZHANG wei-feng XIN xiang-jun ZHANG Qi ZHANG Zi-xing NAI wei SHI Yan School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

A novel architecture for wavelength-division-multiplexing passive optical network （WDM-PON） with centralized light-wave is proposed and demonstrated. At the optical line terminal （OLT） session of this architecture, optical differential quadrature phase shift keying （DQPSK） modulated signal with constant-intensity at 10 Gbit/s is utilized for downstream transmission. At the optical network unit （ONU）, part of the downstream optical power is remodulated with on-off keying （OOK） intensity modulation at 10 Gbit/s for upstream without additional laser. Simulation results show that the power penalties of the downstream for 20 km single-mode fiber （SMF） transmission and multi-channels are negligible. While for the upstream, the power penalties are obvious. The simulation results and analysis also reflect that by reducing the launch power of DQPSK transmitters, power penalties can be reduced, although the transmission distance is limited.

关键词： WDM-PON DQPSK remodulation centralizedlight sources

Pulmonary inflammatory pseudotumor caused by Cryptococcus presenting multiple nodules in bilateral lungs

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The Chinese-German Journal of Clinical Oncology 2006年第6期5卷 460-462页

作者： Ligang Liu Tiecheng Pan xiang wei jun Li Tao Chen Zhi Zheng Department of Thoracic and Cardiac Surgery Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

By now there are a few reports describing a case of pulmonary inflammatory pseudotumor,presenting multiple nodules in bilateral lungs and a pseudotumor caused by fungus infection is also a very rare *** we report a rare case of pulmonary inflammatory pseudotumor with confirmed cause by Cryptococcus infection presenting multiple nodules in bilateral lungs.

关键词： pulmonary fungal inflammatory pseudotumor radiological presentation

A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing Liu xiang Yang jun Liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast ***,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage ***,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation ***,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact *** calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the *** residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged *** results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

Yttrium‐and nitrogen‐doped NiCo phosphide nanosheets for high‐efficiency water electrolysis

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Carbon Energy 2024年第8期6卷 214-231页

作者： Guangliang Chen Huiyang xiang Yingchun Guo jun Huang wei Chen Zhuoyi Chen Tongtong Li Kostya(Ken)Ostrikov Department of Materials Engineering Huzhou UniversityHuzhouChina School of Materials Science and Engineering Zhejiang Sci‐Tech UniversityHangzhouChina School of Physics and Electronic Information Gannan Normal UniversityGanzhouChina School of Chemistry and Physics Centre for Materials ScienceCentre for Clean Energy Technologies and PracticesCentre for Waste−Free WorldQueensland University of Technology(QUT)BrisbaneQueenslandAustralia

Engineering high‐performance and low‐cost bifunctional catalysts for H_(2)(hydrogen evolution reaction[HER])and O_(2)(oxygen evolution reaction[OER])evolution under industrial electrocatalytic conditions remains ***,for the first time,we use the stronger electronegativity of a rare‐Earth yttrium ion(Y^(3+))to induce in situ NiCo‐layered double‐hydroxide nanosheets from NiCo foam(NCF)treated by a dielectric barrier discharge plasma NCF(PNCF),and then obtain nitrogen‐doped YNiCo phosphide(N‐YNiCoP/PNCF)after the phosphating process using radiofrequency plasma in *** obtained NYNiCoP/PNCF has a large specific surface area,rich heterointerfaces,and an optimized electronic structure,inducing high electrocatalytic activity in HER(331mV vs.2000mA cm^(−2))and OER(464mV vs.2000mA cm^(−2))reactions in 1MKOH electrolyte.X‐ray absorption spectroscopy and density functional theory quantum chemistry calculations reveal that the coordination number of CoNi decreased with the incorporation of Y atoms,which induce much shorter bonds of Ni and Co ions and promote long‐term stability of N‐YNiCoP in HER and OER under the simulated industrial ***,the CoN‐YP_(5)heterointerface formed by plasma N‐doping is the active center for overall water *** work expands the applications of rare‐Earth elements in engineering bifunctional electrocatalysts and provides a new avenue for designing highperformance transition‐metal‐based catalysts in the renewable energy field.

关键词： overall water splitting plasma etching plasma N‐doping rare‐earth electrocatalyst yttrium incorporation

Continuous Orbit Equivalence of Semigroup Actions

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1581-1598页

作者： xiang Qi QIANG Cheng jun HOU School of Mathematical Science Yangzhou UniversityYangzhou 225002P.R.China

We introduce notions of continuous orbit equivalence and its one-sided version for countable left Ore semigroup actions on compact spaces by surjective local homeomorphisms,and characterize them in terms of the corresponding transformation groupoids and their operator *** particular,we show that two essentially free semigroup actions on totally disconnected compact spaces are continuously orbit equivalent if and only if there is a canonical abelian subalgebra preserving C^(∗)-isomorphism between the associated transformation groupoid C^(∗)-*** also give some examples of orbit equivalence,consider the special case of semigroup actions by homeomorphisms and relate continuous orbit equivalence of semigroup actions to that of the associated group actions.

关键词： Semigroup action continuous one-sided orbit equivalence continuous orbit equivalence groupoid C^(∗)-algebras

The Crystallization Behavior of L-Poly(lactic acid)/Polypropylene Blends:The Acceleration for Both L-Poly(lactic acid)and Polypropylene

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Chinese Journal of Polymer Science 2024年第6期42卷 775-786页

作者： Shuang-Cheng Li wei-Jia Zhou Wen-Jie Wu jun Shao Shui-Liang Chen Hao-Qing Hou Sheng xiang College of Chemistry&Chemical Engineering and Nanofiber Engineering Center of Jiangxi Province Jiangxi Normal UniversityNanchang330022China National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education Jiangxi Normal UniversityNanchang330022China Wenzhou Institute University of Chinese Academy of SciencesWenzhou325001China

For a polymer/polymer dismissible blend with two crystallizable components,the crystallization behavior of different components and the reciprocal influences between different crystals are interesting and important,but did not investigate in *** this study,the L-poly(lactic acid)/polypropylene(PLLA/PP)blends with different weight ratios were prepared by melt mixing and the crystallization behavior of the blends were *** showed that the crystalline structures of PLLA and PP were not altered by the *** the crystallization of PLLA,both the diffusion of chain segments and crystallization rate were enhanced under the existence of PP *** the crystallization of PP,its crystallization rate was depressed under the existence of amorphous PLLA molecular *** the PP crystallized from the existence of PLLA crystals,although the diffusion rate of PP was reduced by PLLA crystals,the nucleation positions were obviously enhanced,which accelerated the formation of PP *** investigation would supply more basic data for the application of PLLA/PP blend.

关键词： L-poly(lactic acid) Polypropylene Blends Crystalization behavior Crystallization acceleration

Anomalous{1012}tensile twinning and subsequent detwinning in a friction stir processed carbon fiber-reinforced Mg composite

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Journal of Magnesium and Alloys 2024年第4期12卷 1511-1517页

作者： wei Zhao Zhihao Jiang xiang Wu Yujing Liu Haokun Yang jun Wang Qi Liu Xiaochun Liu Institute of Metals College of Materials Science and EngineeringChangsha University of Science&TechnologyChangsha 410114China Department of Mechanical Engineering City University of Hong KongHong KongChina Smart manufacturing division Hong Kong Productivity CouncilHong Kong SAR 999077China Institute for Frontier Materials Deakin UniversityGeelongVIC 3216Australia Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHong KongChina

*** text Owing to their low density and high specific strength,magnesium alloys and magnesium-based composites have great potential as structure metal materials in applications where lightweight matters[1–4].Deformation twins[5],especially the{1012}tension twins(also called tensile or extension twins)with a low critical resolved shear stress(CRSS)[6],are commonly observed in Mg *** can provide the much-needed deformation along the c-axis in their hcp structure resulting from the very few easily activated slip systems in this crystal structure[7].The tensile twinning activation usually follows the macroscopic Schmid factor law[2],i.e.,the twin variant with the highest Schmid factor occurs,and it only appears when its Schmid factor is positive.

关键词： friction deformation magnesium