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Chinese Journal of Chemistry 2024年第16期42卷 1828-1832页

作者： Lingzi Zhao Xuchao Wang Qing qiang Xingwei Zhao Feipeng liu Shenci Lu Zi-qiang rong Frontiers Science Center for Flexible Electronics(FSCFE) Shaanxi Institute of Flexible Electronics(SiFE)&Shaanxi Institute of Biomedical Materials and Engineering(SIBME)Northwestern Polytechnical University(NPU)127 West Youyi RoadXianShaanxi 710072China Honors College Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China

An asymmetric isomerization/intramolecular coupling reaction of allylic alcohols to synthesize chiral dihydrocoumarins was successfully accomplished through ruthenium *** method demonstrates a wide substrate applicability,excellent tolerance for various functional groups,and good enantioselectivities(up to 90%ee).It provides a convenient pathway to produce a diverse range ofstructurallydistinct chiral dihydrocoumarins ingoodefficiency.

关键词： Ruthenium catalysis Asymmetric isomerization Tandem reaction Chiral dihydrocoumarins Enantioselectivity

Energy saving analysis for CO_(2)–O_(2)mixed injection technology in converter steelmaking

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Journal of Iron and Steel Research International 2024年第5期31卷 1095-1103页

作者： Bao-chen Han Chun-liang Gao Ya-qiang Li Dan liu Guang-sheng Wei rong Zhu Hebei Key Laboratory of Material Near-Net Forming Technology School of Material Science and EngineeringHebei University of Science and TechnologyShijiazhuang050018HebeiChina Department of Automotive Engineering Hebei Vocational University of Technology and EngineeringXingtai054000HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

Energy-saving in China's iron and steel industry still relies on the development and improvement of short-term energy saving ***,a special converter smelting technology incorporating energy saving was *** evaluate the energy-saving potential of the CO_(2)–O_(2)mixed injection(COMI)technology,collected production data were used to develop an improved techno-economic *** reveal that the technology can save energy through auxiliary material consumption,sensible heat of solid by-product,iron loss reduction,and energy *** application of COMI technology in an enterprise is cost effective,involving the energy saving potential of 0.206 GJ/t,the cost of conserved energy of−48.83 yuan/GJ,and a simple payback period of 0.35 year for a 60-million-yuan *** analysis shows that the investment cost and discount rate primarily influence the cost of conserved energy of the *** the discount rate increased,the cost of conserved energy also gradually ***,the COMI technology is an energy-saving technology with good development prospects.

关键词： Converter steelmaking COMI technology Energy saving Techno-economic model Investment cost

Understanding microstructure-property relationships of HPDC Al-Si alloy based on machine learning and crystal plasticity simulation

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Advances in Manufacturing 2024年第3期12卷 497-511页

作者： qiang-qiang Zhai Zhao liu Ping Zhu State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China National Engineering Research Center of Automotive Power and Intelligent Control Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China School of Design Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China

Al-Si alloys manufactured via high-pressure die casting(HPDC)are suitable for a wide range of ***,the heterogeneous microstructure and unpredictable pore distribution of Al-Si high-pressure die castings result in significant variations in the mechanical properties,thus leading to a complicated microstructure-property relationship that is difficult to ***,a computational framework incorporating machine learning and crystal plasticity method is *** framework aims to provide a systematic and comprehensive understanding of this relationship and enable the rapid prediction of macroscopic mechanical properties based on the ***,we select eight variables that can effectively characterize the microstructural features and then obtain their statistical ***,based on 160 samples obtained via the Latin hypercube sampling method,representative volume elements are constructed,and the crystal plasticity fast Fourier transformation method is executed to obtain the macroscopic mechanical ***,the yield strength,elastic modulus,strength coefficient,and strain-hardening exponent are used to characterize the stress-strain curve,and Gaussian process regression models and microstructural variables are ***,sensitivity and univariate analyses based on these machine-learning models are performed to obtain insights into the microstructure-property relationships of the HPDC Al-Si *** results show that the Gaussian process regression models exhibit high accuracy(R2 greater than 0.84),thus confirming the viability of the proposed *** results of sensitivity analysis indicate that the pore size exerts the most significant effect on the mechanical ***,the proposed framework can not only be transferred to other alloys but also be employed for material design.

关键词： High-pressure die casting(HPDC) Machine learning Crystal plasticity Aluminum alloys

Non-contact and full-field online monitoring of curing temperature during the in-situ heating process based on deep learning

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Advances in Manufacturing 2024年第1期12卷 167-176页

作者： qiang-qiang liu Shu-Ting liu Ying-Guang Li Xu liu Xiao-Zhong Hao College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing211816People’s Republic of China

Online monitoring of the curing temperature field is essential to improving the quality and efficiency of the manufacturing process of composite *** embedded sensor-based technologies have difficulty monitoring the full temperature field or have to introduce heterogeneous items that could have an undesired impact on the *** this paper,a non-contact,full-field monitoring method based on deep learning that predicts the internal temperature field of composite parts in real time using surface temperature measurements of auxiliary materials is *** the proposed method,an average temperature monitoring accuracy of 97%is achieved in various heating *** addition,this method also demonstrates satisfying feasibility when a stronger thermal barrier covers the *** method was experimentally validated during the self-resistance electric heating process,in which the monitoring accuracy reached 93.1%.This method can potentially be applied to automated manufacturing and process control in the composites industry.

关键词： Online monitoring Curing temperature field Deep learning(DL) In-situ heating

Spontaneous Infection and Periodic Evolving of Domain in a Diffusive SIS Epidemic Model

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 164-191页

作者： qiang Wen Guo-qiang Ren Bin liu School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan430074China

In this paper, we consider a susceptible-infective-susceptible(SIS) reaction-diffusion epidemic model with spontaneous infection and logistic source in a periodically evolving domain. Using the iterative technique,the uniform boundedness of solution is established. In addition, the spatial-temporal risk index R0(ρ) depending on the domain evolution rate ρ(t) as well as its analytical properties are discussed. The monotonicity of R0(ρ)with respect to the diffusion coefficients of the infected dI, the spontaneous infection rate η(ρ(t)y) and interval length L is investigated under appropriate conditions. Further, the existence and asymptotic behavior of periodic endemic equilibria are explored by upper and lower solution method. Finally, some numerical simulations are presented to illustrate our analytical results. Our results provide valuable information for disease control and prevention.

关键词： diffusive SIS model spontaneous infection periodically evolving domain periodic endemic equilibrium

Harmful evaluation of heavy metals from soil layer to the groundwater: Take the Jilin Hunchun Basin as an example

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China Geology 2024年第1期7卷 116-124页

作者： Xiao-Dong Guo qiang liu Hui-rong Zhang Xu-Fei Shi Chuan-Yu Qin Zhi-qiang Zhang Shenyang Geological Survey Center China Geological SurveyMinistry of Natural ResourcesShenyang 110034China Key Laboratory of Black Land Evolution and Ecological Effects Shenyang 110034China New Energy and Environment College Jilin UniversityChangchun 130026China Jilin Hydrogeological Survey Institute Changchun 130026China

The continuous enrichment of heavy metals in soils has caused potential harm to *** methods to evaluate the harm of heavy metals in soil to groundwater are lacked in previous *** on the theory of groundwater circulation and solid-liquid equilibrium,a simple and easy-touse flux model of soil heavy metals migrating to groundwater is *** on groundwater environmental capacity,an innovative method for evaluating the harm of heavy metals in soil to groundwater is proposed,which has been applied in Hunchun Basin,Jilin Province,*** results show that the fluxes of soil heavy metals into groundwater in the study area are Zn,Cu,As,Pb,Cd,Ni,and Hg in descending *** content of heavy metals in groundwater(As,Hg,Cu,Pb,Zn,Ni,and Cd)in most areas has not risen to the threshold of environmental capacity within 10 *** harm levels of soil heavy metals to groundwater in the most townships soils are at the moderate level or *** evaluation method can quantify the flux of soil heavy metals into groundwater simply and quickly,determine the residual capacity of groundwater to heavy metals,evaluate the harm level of soil heavy metals to groundwater,provide support for relevant departments to carry out environmental protection of soil and groundwater,and provide a reference to carry out similar studies for related scholars.

关键词： Soil heavy metals As+Hg+Cu+Pb+Zn+Ni+Cd Environmental capacity Groundwater Hazard degree Migration flux model Agricultural geological survey engineering Hunchun Basin Jilin Province

Remote sensing image encryption algorithm utilizing 2D Logistic memristive hyperchaotic map and SHA-512

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Science China(Technological Sciences) 2024年第5期67卷 1553-1566页

作者： LAI qiang liu Yuan YANG Liang School of Electrical and Automation Engineering East China Jiaotong UniversityNanchang330013China

The two-dimensional Logistic memristive hyperchaotic map(2D-LMHM)and the secure hash SHA-512 are the foundations of the unique remote sensing image encryption algorithm(RS-IEA)suggested in this *** proposed map is formed from the improved Logistic map and the memristor,which has wide phase space and hyperchaotic range and is exceptionally excellent to be utilized in specific *** proposed image algorithm uses the permutation-assignment-diffusion *** generates two position matrices in a progressive manner to achieve an efficient random exchange of pixel positions,assignment is carried through on the image pixels of the permutated image to entirely remove the original image information,strengthening the relationship between permutation and diffusion,and loop diffusion in two different directions can use subtle changes of pixels to affect the whole *** random key and plain-image SHA-512 hash values are used to produce an additional key,which is then utilized to figure out the permutation parameters and the initial value of a chaotic *** experimental results with the average NPCR=99.6094%(NPCR:number of pixels change rate),average UACI=33.4638%(UACI:unified average changing intensity),100%pass rate of the targets in the test set,the average correlation coefficient is 0.00075,and the local information entropy is 7.9025,which shows that the algorithm is able to defend against a variety of illegal attacks and provide more trustworthy protection than some of the existing state-of-the-art algorithms.

关键词： chaos memristive hyperchaotic map remote sensing SHA-512 image encryption RS-IEA

Regulating the conductance of tungsten diselenide by oxygen plasma and improving its electrical stability by encapsulation

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Nano Research 2024年第4期17卷 3253-3260页

作者： Zhaofang Cheng Shaodan He Shimin Zhang Shijun Duan Min Wang Ziyu liu rong Zhang Wenya qiang Xudong Zhang Minggang Xia MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter School of PhysicsXi’an Jiaotong UniversityXi’an 710049China Department of Applied Physics School of PhysicsXi’an Jiaotong UniversityXi’an 710049China Shaanxi Province Key Laboratory of Quantum Information and Optoelectronic Quantum Devices School of PhysicsXi’an Jiaotong UniversityXi’an 710049China

Two-dimensional(2D)tungsten selenide(WSe_(2))is promising candidate material for future electronic applications,owing to its potential for ultimate device *** improving the electronic performance of WSe_(2)-based field-effect transistors(FETs),the modification of surface properties is *** this study,the seamless structural phase transition in WSe_(2) lattice is achieved by soft oxygen plasma,regulating the electrical conductance of WSe_(2)-based *** found that during the soft oxygen plasma treatment with optimal processing time,the generated oxygen ions can substitute some selenium atoms and thus locally modify the bond length,inducing 2H→1T phase transition in WSe_(2) with seamless *** mosaic structures have been proven to tailor the electronic structure and increase the hole carrier concentration inside WSe_(2),significantly increasing the channel conductance of WSe_(2) *** the further increase of the oxygen plasma treatment time,the creation of more selenium vacancy defects leads to the electronic doping,resulting in the reduction of *** from the hexagonal boron nitride(h-BN)encapsulation to interrupt the partial structural relaxation from 1T to 2H phase,our WSe_(2) FET exhibits high electronic stability with conductance of 6.8×10^(-4) S,which is about four orders of magnitude higher than 2H WSe_(2)(5.8×10^(-8) S).This study could further broaden the WSe_(2) FETs in applications for functionalization and integration in electronics.

关键词： tungsten selenide(WSe2) structural phase transition oxygen plasma conductance hexagonal boron nitride(h-BN)encapsulation

Empirical likelihood for spatial cross-sectional data models with matrix exponential spatial specification

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 125-139页

作者： liu Yan rong Jian-rong QIN Yong-song Nanning University Nanning 530200China Center for Applied Mathematics of Guangxi and College of Mathematics and Statistics Guangxi Normal UniversityGuilin 541004China

In this paper,we study spatial cross-sectional data models in the form of matrix exponential spatial specification(MESS),where MESS appears in both dependent and error *** empirical likelihood(EL)ratio statistics are established for the parameters of the MESS *** is shown that the limiting distributions of EL ratio statistics follow chi-square distributions,which are used to construct the confidence regions of model *** experiments are conducted to compare the performances of confidence regions based on EL method and normal approximation method.

关键词： MESS empirical likelihood con dence region

Absorbable bandage wrapping in treatment of severe blast liver injury： a miniature swine model

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Chinese Medical Journal 2011年第22期124卷 3757-3761页

作者： LU Can-rong CHEN Lin CHEN Wen-bin DOU Chun-qing liu rong HUANG Zhi-qiang Department of General Surgery Chinese People＇s Liberation Army General Hospital Beijing 100853 China

Background The aim of this research was to evaluate the feasibility and efficacy of absorbable bandage wrapping in the treatment of cases of severe liver trauma. Methods Electric firecrackers were detonated in 16 miniature swine to produce a severe blast liver injury. After fluid resuscitation, the animals were randomly divided into two groups （n=-8 each） and were either treated with absorbable bandage wrapping of the injured lobe of liver （Group B） or hepatic Iobectomy （Group H）. Time to hemostasis, blood loss during the treatment period, and other parameters were compared, including postoperative serum total bilirubin （TB）, alanine aminotransferase （ALT）, and aspartate aminotransferase （AST）. Results Blood loss during the treatment period was significantly lower in Group B than that in Group H （（81.3±26.0） ml vs. （130.8±2.9.5） ml, P=0.0031）. Serum AST and ALT were transiently increased post-surgically. These transient increases were significantly higher in Group B. No difference in time to hemostasis was noted （（8.70±2.27） minutes vs. （10.28±1.93） minutes, P=-0.1559） in Groups B and H, respectively. Two pigs were humanely euthanized 28 days post-surgically and the wrapped liver lobes appeared atrophies. Microscopically, there was evidence of emerging and mature fibrous tissue. Conclusion Absorbable bandaqe wrappinQ is both feasible and effective in the treatment of severe blast liver injury.

关键词： wounds and injuries bandage hemostasis, surgical hepatectomy models, animal