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Theoretical Study on Vibrational Spectra, Detonation Properties and Pyrolysis Mechanism for Cyclic 2-Diazo-4,6-dinitrophenol

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Chinese Journal of Chemical Physics 2012年第5期25卷 545-551,I0003页

作者： Xiao-hong Li Geng-xin Yin xian-zhou Zhang College of Physics and Engineering Henan University of Science and TechnologyLuoyang 471003China Luoyang Key Laboratory of Photoelectric Functional Materials Henan University of Science andTechnologyLuoyang 471023China College of Physics and Information Engineering Henan Normal UniversityXinxiang 453007China

Based on the full optimized molecular geometrical structures at the DFT-B3LYP/6- 311＋G^＊＊ level, there exists intramolecular hydrogen bond interaction for cyclic 2-diazo- 4,6-dinitrophenol. The assigned infrared spectrum is obtained and used to compute the thermodynamic properties. The results show that there are four main characteristic regions in the calculated IR spectra of the title compound. The detonation velocities and pressures are also evaluated by using Kamlet-Jacobs equations based on the calculated density and condensed phase heat of formation. Thermal stability and the pyrolysis mechanism of 2- diazo-4,6-dinitrophenol are investigated by calculating the bond dissociation energies at the B3LYP/6-311＋G^＊＊ level.

关键词： Cyclic 2-diazo-4 6-dinitrophenol Pyrolysis mechanism Detonation property Infrarecl spectrum

Segregation in squeeze casting 6061 aluminum alloy wheel spokes and its formation mechanism

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China Foundry 2021年第1期18卷 45-51页

作者： Fan-bo meng hong-jun Huang Xiao-guang Yuan Xue-jian Lin Ze-wen Cui xian-lei Hu School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China School of Materials Science and Engineering Liaoning Technology UniversityFuxin123000China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110004China

Segregation can seriously damage the mechanical properties of the aluminum alloys.6061 aluminum alloy wheel spokes were prepared by squeeze *** investigate the formation mechanism of segregation,the microstructure of the alloy was observed using scanning electron microscopy,energy dispersive spectrometry,X-ray diffraction and electron microprobe analysis *** Gibbs energy of each phase during solidification was calculated by JMat *** show that the segregation phases in the R-joint of the wheel spokes are mainly composed of Mg_(2)Si,β-Al Fe Si and Al_(5)Cu_(2)Mg_(8)Si_(6)*** the solidification of the 6061 aluminum alloy wheels,Mg_(2)Si andα-Al Fe Si phases precipitate in the mushy zone at *** the decrease of temperature,α-Al Fe Si transforms intoβ-Al Fe Si,while Al_(5)Cu_(2)Mg_(8)Si_(6)precipitates from the solid-state aluminum alloy after *** at the R-joint of wheel spokes is mainly caused by insufficient cooling,so the cooling during alloy solidification should be enhanced to avoid segregation.

关键词： 6061 aluminum wheels segregation squeeze casting Mg_(2)Si Al FeSi Al_(5)Cu_(2)Mg_(8)Si_(6)

Periodic Layered Structure Formed during Interfacial Reaction

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Journal of Iron and Steel Research International 2016年第11期23卷 1127-1133页

作者： xian-man ZHANG hong-feng LUO Liu-yong SHI Institute of Electrical and Mechanical Engineering Hainan University

A review of the periodic layered structure （PLS） formed during reactive diffusion was presented. The formation of PLS is a very interesting and complex phenomenon during the reactive diffusion process. It was firstly discovered occasionally. The formation of PLS has been reported in various solid state diffusion couples such as Zn/ Ni3 Si, Mg/SiO2, Zn/Cux Tiy and so on, and some controversial theoretical models and formation mechanism of PLS were put forward. However, there have been few reports about the PLS formed during hot dip. The development of PLS was reviewed, and the recent progress referring to the formation of PLS during the hot dip aluminizing of a no- vel Fe-Cr-B cast steel was especially introduced. However, not all of the borides could form PLS in their interracial reaction with molten Al. PLS only formed at the Cr-rich Fe2B/Al interface, while Mo-rich Fe2B fractured. A general qualitative description for the interracial reaction of Fe-Cr-B cast steel with molten Al was represented. Further inves- tigation on the constituents of the alternating phases and formation mechanism of PLS needs to be done. At last, the development trends of PLS were proposed.

关键词： periodic layered structure interfacial reaction reactive diffusion formation mechanism Fe-Cr-B cast steel

A FEASIBLE DIRECTION ALGORITHM WITHOUT LINE SEARCH FOR SOLVING MAX-BISECTION PROBLEMS

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Journal of Computational Mathematics 2005年第6期23卷 619-634页

作者： Feng-min Xu Cheng-xian Xu hong-gang Xue Department of Mathematics of Faculty of Science Xi'an Jiaotong University Xi'an 710049 China

This paper concerns the solution of the NP-hard max-bisection problems. NCP functions are employed to convert max-bisection problems into continuous nonlinear programming problems. Solving the resulting continuous nonlinear programming problem generates a solution that gives an upper bound on the optimal value of the max-bisection problem. From the solution, the greedy strategy is used to generate a satisfactory approximate solution of the max-bisection problem. A feasible direction method without line searches is proposed to solve the resulting continuous nonlinear programming, and the convergence of the algorithm to KKT point of the resulting problem is proved. Numerical experiments and comparisons on well-known test problems, and on randomly generated test problems show that the proposed method is robust, and very efficient.

关键词： Max-Bisection problem Feasible direction algorithm NCP function Convergence

Fluidity of ADC12+xLa aluminum alloys

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Rare Metals 2021年第5期40卷 1191-1197页

作者： Zheng-Hua Li hong Yan Zhi Hu xian-Chen Song Department of Materials Processing Engineering School of Mechanical and Electrical EngineeringNanchang UniversityNanchang 330031China Key Laboratory of Light Alloy Preparation&Processing in Nanchang Nanchang 330031China

The influence of rare earth lanthanum and pouring temperature on the fluidity of ADC 12 aluminum alloy was studied through spiral fluidity specimens by means of optical microscopy(OM) and differential thermal analyzer(DTA).The least squares regression method was used to give the best fitting between the function and the experimental *** experimental results indicate that the rare earth lanthanum can significantly increase the fluidity of ADC 12 *** fluidity increases with the addition of *** DTA results indicate that with the addition of lanthanum,the range of crystallization temperature decreases,which increases the fluidity ***,the range of crystallization temperature decreases by 32.66 % and the fluidity length is 1,321 mm(increased by 38.91%) when the addition of lanthanum is 0.6 wt%.Furthermore,with the increase of pouring temperatures,the fluidity length increases linearly between 670 and 760℃.

关键词： Fluidity Aluminum alloys Rare earth Pouring temperature

Soil properties and corn(Zea mays L.)production under manure application combined with deep tillage management in solonetzic soils of Songnen Plain,Northeast China

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Journal of Integrative Agriculture 2016年第4期15卷 879-890页

作者： meng Qing-feng LI Da-wei ZHANG Juan ZHOU Lian-ren MA xian-fa WANG hong-yan WANG Guang-cheng School of Resources and Environment Northeast Agricultural UniversityHarbin 150030P.R.China Center of Zhaozhou County on Popularization of Agricultural Technology zhaozhou 166400P.R.China

Poor soil structure and nutrients, excessive exchangeable Na＋, high pH as well as low enzyme activities are common in the solonetz, and significantly restrict corn （Zea mays L.） production. Cattle manure application combined with deep tillage is an important management practice that can affect soil physico-chemical properties and enzyme activities as well as corn yield in the solonetz. Field experiments were carried out in a randomized complete block design comprising four treatments： Corn with conventional tillage was used as a control, and corn with manure application combined with deep tillage as well as film mulching and aluminium sulfate were used as the experimental treatments, respectively. The relationship between corn yield and measured soil properties was determined using stepwise regression analysis. Manure application combined with deep tillage management was more effective than conventional tillage for increasing corn yield and for improving soil properties in the solonetz. The highest corn yield was obtained in the treatments with manure application＋deep tillage＋plastic film mulching （11 472 and 12 228 kg ha-l）, and increased by 38 and 43% comparing with the control treatment （8 343 and 8 552 kg ha-1） both in the 2013 and 2014 experiments, respectively. Using factor analysis, three factors were obtained, which represented soil fertility status, soil saline-alkaline properties and soil structural properties both in the 2013 and 2014 experiments, respectively. Manure and deep tillage management resulted in two distinct groups of soil properties：（1） soils with manure application combined with deep tillage and （2） soils with conventional tillage. Stepwise regression analysis showed that corn yield was significantly and positively correlated to urease and available P, as well as negatively correlated to pH, electrical conductivity （EC）, exchange sodium percentage （ESP）, and bulk density （Pb）. We concluded that Pb was dominant factor for corn yield on the b

关键词： cattle manure deep tillage corn yield solonetz

Atorvastatin ameliorated myocardial fibrosis in db/db mice by inhibiting oxidative stress and modulating macrophage polarization

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World Journal of Diabetes 2023年第12期14卷 1849-1861页

作者： xian-Min Song meng-Nan Zhao Gui-Zhi Li Na Li Ting Wang hong Zhou Department of Endocrinology The Second Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Geriatrics Handan Central HospitalHandan 056001Hebei ProvinceChina

BACKGROUND People with diabetes mellitus(DM)suffer from multiple chronic complications due to sustained hyperglycemia,especially diabetic cardiomyopathy(DCM).Oxidative stress and inflammatory cells play crucial roles in the occurrence and progression of myocardial *** polarize to two distinct phenotypes:M1 and M2,and such plasticity in phenotypes provide macrophages various biological *** To investigate the effect of atorvastatin on cardiac function of DCM in db/db mice and its underlying *** DCM mouse models were established and randomly divided into DM,atorvastatin,and metformin groups.C57BL/6 mice were used as the *** function was evaluated by *** and eosin and Masson staining was used to examine the morphology and collagen fibers in myocardial *** expression of transforming growth factor-β1(TGF-β1),tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),M1 macrophages(iNOS^(+)),and M2 macrophages(CD206^(+))were demonstrated by immunohistochemistry and immunofluorescence *** levels of TGF-β1,IL-1β,and TNF-αwere detected by ELISA and real-time quantitative polymerase chain ***(MDA)concentrations and superoxide dismutase(SOD)activities were also *** Treatment with atorvastatin alleviated cardiac dysfunction and decreased db/db mice. The broken myocardialfibers and deposition of collagen in the myocardial interstitium were relieved especially by atorvastatin *** also reduced the levels of serum lactate dehydrogenase, creatine kinase isoenzyme, and troponin;lowered the levels of TGF-β1, TNF-α and IL-1β in serum and myocardium;decreased the concentration of MDAand increased SOD activity in myocardium of db/db mice;inhibited M1 macrophages;and promoted *** Administration of atorvastatin attenuates myocardial fibrosis in db/db mice, which may be associated with theantioxidative stress and anti-inflammato

关键词： Atorvastatin Diabetic cardiomyopathy Myocardial fibrosis Macrophage polarization Inflammation Oxidative stress

New Applications of the <λ| Representation in Studying the Angular Momentum of Laughlin State Vector

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Chinese Physics Letters 2001年第4期18卷 469-472页

作者： FAN hong-Yi LIN Jing-xian Department of Applied Physics Shanghai Jiao Tong UniversityShanghai 200030 Department of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026

We use the complete and orthonormal , where ||0 > is annihilated by ( II-,K-). Following this, we further employ the <λ| representation to derive the angular momentum of the Laughlin ground state and excited state in... 详细信息

关键词： representation state excited

Forming the transverse inner rib of a curved generatrix part through power spinning

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Advances in Manufacturing 2019年第1期7卷 105-115页

作者： hong-Rui Zhang Mei Zhan Jing Guo xian-xian Wang Peng-Fei Gao Fei Ma State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 People's Republic of China Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 People's Republic of China Long March Machinery Factory China Aerospace Science and Technology Corporation Chengdu 610100 People's Republic of China

How to form high-quality transverse inner ribs through power spinning is a key issue for complicated integrated curved generatrix parts with transverse inner ribs. In this study, the forming characteristics and laws during the power spinning process were investigated using a finite element simulation based on the orthogonal design method. The results show that the transverse inner rib distributes homogeneously along the circumferential direction but inhomogeneously along the generatrix direction. Depressions occur easily in the middle zone of the rib (MZR). The roller nose radius is the most significant parameter of the MZR underfill degree. A larger roller nose radius is helpful to decrease the MZR underfill degree. Furthermore, the preformed billet thickness also plays a vital role in the underfill degree of the front zone of the rib and the back zone of the rib, as well as the depression degree of the outer surface of the rib. By combining the ribfilling characteristics and laws, the optimized forming process window for obtaining high-quality inner ribs was obtained by regression analysis, thus laying a basis for improving the forming quality of curved generatrix parts with transverse inner ribs in power spinning.

关键词： Power spinning Transverse inner rib Rib filling Process optimization