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Visible-light-induced Synthesis of Organic Peroxides via Decarboxylative Couplings of Carboxylic Acids, Alkenes and tert-Butyl Hydroperoxide

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CHEMICAL RESEARCH IN CHINESE UNIVERSITIES 2024年第5期40卷 863-873页

作者： Huang, Qiuwei Lou, Chenhao lv, Leiyang Li, Zhiping Renmin Univ China Sch Chem & Life Resources Key Lab Adv Light Convers Mat & Biophoton Beijing 100872 Peoples R China

Herein, we present a photoinduced, CeCl3-catalyzed three-component decarboxylative reaction that couples carboxylic acids, alkenes and tert-butyl hydroperoxide for the formation of various organic peroxides. The ligand-to-metal charge transfer (LMCT) excitation mode allows the decarboxylative alkylation-peroxidation reaction to occur under mild conditions, and is well applicable to primary, secondary and tertiary carboxylic acids and styrene derivatives.

关键词： Visible-light catalysis Difunctionalization Carboxylic acid Alkene Organic peroxide CATALYZED CARBONYLATION-PEROXIDATION OXIDATIVE DECARBOXYLATION RADICAL-ADDITION ALDEHYDES ALKYLATION KETONES SCOPE MILD

Random change point model with an application to the China Household Finance Survey

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Science China Mathematics 2024年第10期67卷 2373-2386页

作者： Meng Li lingxi Gao Guangming lv Xingwei Tong School of Statistics Beijing Normal UniversityBeijing 100875China

We consider a linear model with a change point according to the unknown random threshold of a covariate. We give the expectation-maximization(EM) estimations of the regression and change point parameters. The existence of the random change point is detected by the supremum(SUP) test of score statistics. Theoretically, we establish the convergence and asymptotic distribution of the estimation and show that the EM estimates converge in distribution to a normal distribution. In addition, the numerical performance of the proposed approach is demonstrated through simulation studies. Finally, applying our methodology to household financial decisions, we see that the average debt tolerance of Chinese households is estimated to be 1.1364 times the sum of total household income and financial assets. The effect of assets and income on consumption shows a rapid decline if the household exceeds the average debt tolerance.

关键词： random change point EM algorithm SUP test debt nancial vulnerability

Exceptional reversed yield strength asymmetry in a rare-earth free Mg alloy containing quasicrystal precipitates

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Journal of Magnesium and Alloys 2024年第2期12卷 687-699页

作者： Qiang Yang Shuhui lv Zixiang Yan Zefeng Xie Xin Qiu State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022PR China School of Materials Science and Engineering Changchun University of Science and Technology130022PR China

This work reports an exceptional reversed yield strength asymmetry at room temperature for a rare-earth free magnesium alloy containing a mass of fine dispersed quasicrystal(I-phase)*** exhibiting traditional basal texture,it owns an exceptional CYS/TYS as high as~*** back-scattered diffraction(EBSD)and transmission electron microscopy(TEM)examinations indicate pyramidal and prismatic dislocations plus tensile twinning being activated after immediate yielding in compression while basal and non-basal dislocations in tension.I-phase particles transferred the concentrated stress by self-twinning to provide the driving force for tensile twin initiating in neighboring grains,thereby significantly increasing the critical resolved shear stress of tensile twinning to possibly the level of pyramidal slip,finally leading to the dominance of pyramidal slip plus tensile twinning in texture *** results in a higher contribution on yield strength by~55 MPa in compression than in tension,which reasonably agrees with the experimental yield strength difference(~38 MPa).It can be concluded that I-phase particles influence deformation modes in tension and in compression,finally result in reversed yield strength asymmetry.

关键词： Magnesium alloy Reversed yield strength asymmetry Transmission electron microscopy(TEM) Twinning Dislocations

Energy consumption optimization for edge computing-supported cellular networks based on optimal transport theory

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Science China(Information Sciences) 2024年第2期67卷 201-218页

作者： Xiangyu lv Xiaohu GE Yi ZHONG Qiang LI Yong XIAO School of Electronic Information and Communications Huazhong University of Science and Technology

With advancements in mobile communication technologies, there have been multiple user device(UD) connections to cellular networks. Because of changes in the spatial distribution of UDs and application requirements, the traditional offloading mechanism based on the nearest distance will result in heavy loads for some base stations(BSs). Because there is a high-order relationship between the energy consumption of the BS processing tasks and the number of computing tasks, the traditional offloading mechanism will result in high energy consumption, and UD’s offloading decision must be dynamically adjusted. The offloading decision of UDs is optimized based on detailed information about various parameters associated with a network from the standpoint of distribution. This information includes details regarding the spatial distribution of UDs,application requirements, and the offloading period of computing tasks. Based on optimal transport theory,an energy consumption optimization algorithm is suggested to lower the total amount of energy consumed by the offloading process of UDs’ computing tasks by reasonably planning the offloading BSs of the UDs in the networks. The simulation results show that the proposed offloading mechanism based on energy consumption optimization reduces the total energy consumption of the offloading process by 28.09% when compared to the traditional offloading mechanism, and the traffic managed by each BS is balanced.

关键词： optimal transport theory edge computing energy consumption reduction dynamic voltage frequency scaling

Crystal structure,phase transitions,and thermodynamic properties of magnesium metavanadate(MgV_(2)O_(6))

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Journal of Magnesium and Alloys 2024年第4期12卷 1449-1460页

作者： Guishang Pei Cheng Pan Dapeng Zhong Junyi Xiang Xuewei lv College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and Advanced Materials Chongqing UniversityChongqing 400044China Pangang Group Research Institute Co. Ltd.Panzhihua 617000China

As a promising anode material for magnesium ion rechargeable batteries,magnesium metavanadate(MgV_(2)O_(6))has attracted considerable research interest in recent years.A MgV_(2)O_(6)sample was synthesized via a facile solid-state reaction by multistep-firing stoichiometric mixtures of MgO and V2O5 powder under an air *** solid-state phase transition fromα-MgV_(2)O_(6)toβ-MgV_(2)O_(6)occurred at 841 K and the enthalpy change was 4.37±0.04 kJ/*** endothermic effect at 1014 K and the enthalpy change was 26.54±0.26 kJ/mol,which is related to the incongruent melting ofβ-MgV_(2)O_(6).In situ XRD was performed to investigate phase transition of the as-prepared MgV_(2)O_(6)at high *** cell parameters obtained by Rietveld refinement indicated that it crystallizes in a monoclinic system with the C2/m space group,and the lattice parameters of a=9.280 A°,b=3.501 A°,c=6.731 A°,β=111.76°.The solid-state phase transition fromα-MgV_(2)O_(6)toβ-MgV_(2)O_(6)was further studied by thermal kinetics,indicating that this process is controlled first by a fibril-like mechanism and then by a spherulitic-type mechanism with an increasing heating ***,the enthalpy change of MgV_(2)O_(6)at high temperatures was measured utilizing the drop calorimetry,heat capacity was calculated and given as:Cp=208.3+0.03583T-4809000T^(−2)(298-923 K)(J mol^(−1)K^(−1)),the high-temperature heat capacity can be used to calculate Gibbs free energy of MgV_(2)O_(6)at high temperatures.

关键词： MgV_(2)O_(6) Crystal structure Phase transitions Thermodynamic functions

Point Cloud Classification Using Content-Based Transformer via Clustering in Feature Space

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 231-239页

作者： Yahui Liu Bin Tian Yisheng lv lingxi Li Fei-Yue Wang the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190 the School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100190 IEEE the Transportation and Autonomous Systems Institute(TASI)and the Department of Electrical and Computer Engineering Purdue School of Engineering and TechnologyIndiana University-Purdue University Indianapolis(IUPUI)Indianapolis 46202 USA

Recently, there have been some attempts of Transformer in 3D point cloud classification. In order to reduce computations, most existing methods focus on local spatial attention,but ignore their content and fail to establish relationships between distant but relevant points. To overcome the limitation of local spatial attention, we propose a point content-based Transformer architecture, called PointConT for short. It exploits the locality of points in the feature space(content-based), which clusters the sampled points with similar features into the same class and computes the self-attention within each class, thus enabling an effective trade-off between capturing long-range dependencies and computational complexity. We further introduce an inception feature aggregator for point cloud classification, which uses parallel structures to aggregate high-frequency and low-frequency information in each branch separately. Extensive experiments show that our PointConT model achieves a remarkable performance on point cloud shape classification. Especially, our method exhibits 90.3% Top-1 accuracy on the hardest setting of ScanObjectN N. Source code of this paper is available at https://***/yahuiliu99/PointC onT.

关键词： Content-based Transformer deep learning feature aggregator local attention point cloud classification

Effect of cuproptosis on acute kidney injury after cardiopulmonary bypass in diabetic patients

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World Journal of Diabetes 2024年第10期15卷 2123-2134页

作者： Xi-Jin Deng Yi-Nan Wang Chuan-Bao lv Zhong-Zhi Qiu ling-Xin Zhu Jing-Hui Shi Si-Ri-Gu-Leng Sana Department of Anesthesiology The Second Affiliated Hospital of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina Department of The Health Management Service Evaluation Center The Health Management Service Evaluation Center of Heilongjiang ProvinceHarbin 150000Heilongjiang ProvinceChina Department of Anesthesiology The First Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 150001Guangdong ProvinceChina Department of Anesthesiology The First Affiliated Hospital of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina Department of Thoracic Surgery The First Affiliated Hospital of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina

BACKGROUND Cardiopulmonary bypass(CPB)is a common procedure in cardiac *** is a high-risk factor for acute kidney injury(AKI),and diabetes is also such a *** can lead to copper *** is currently unclear whether AKI after CPB in diabetic patients is related to copper *** To explore whether the occurrence of CPB-AKI in diabetic patients is associated with *** Blood and urine were collected from clinical diabetic and non-diabetic patients before and after *** of copper ion,lactate,glucose,heat shock protein-70(HSP-70),and dihydrolipoamide dehydrogenase(DLAT)were determined.A diabetic rat model was established and CPB was *** rats were assessed for the development of CPB-AKI,and for the association of AKI with cuproptosis by detecting copper levels,iron-sulfur cluster proteins and observation of mitochondrial structure by electron *** CPB resulted in elevations of copper,lactate,HSP-70 and DLAT in blood and urine in both diabetic and nondiabetic *** was associated with pathologic and mitochondrial damage in the kidneys of diabetic ***-related proteins also appeared to be significantly *** CPB-AKI is associated with *** mellitus is an important factor aggravating CPB-AKI and cuproptosis.

关键词： Cardiopulmonary bypass Acute kidney injury Cuproptosis Diabetes Copper overload Iron-sulfur cluster proteins

基于现代信息技术发展的高校思政教学提质增效研究

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四川工商学院学术新视野 2024年第2期9卷 47-50页

作者：吕羚成都锦城学院四川成都611731

现代信息技术赋能高校教育已成为当前发展的必然趋势,各种新型教育教学理念及课程教学资源也逐步被引入其中,教育现代化的发展目标逐步实现,高校教育新生态正在形成。本文立足于高校思想政治教学实践,就现代信息技术促进思政教学提质增... 详细信息

现代信息技术赋能高校教育已成为当前发展的必然趋势,各种新型教育教学理念及课程教学资源也逐步被引入其中,教育现代化的发展目标逐步实现,高校教育新生态正在形成。本文立足于高校思想政治教学实践,就现代信息技术促进思政教学提质增效的相关方面进行深入分析和探究。

关键词：现代信息技术高校思想政治教学提质增效

Rupture of a giant jejunal mesenteric cystic lymphangioma misdiagnosed as ovarian torsion: A case report

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World Journal of Clinical Cases 2024年第4期12卷 847-852页

作者： Jing Xu Tie-Feng lv Department of Hepatopathy Hangzhou Xixi HospitalHangzhou 310023Zhejiang ProvinceChina

BACKGROUND Cystic lymphangioma is a rare benign tumor that affects the lymphatic *** lymphangiomas in the small bowel are extremely *** SUMMARY We present a 21-year-old female patient who complained of abdominal *** diagnosis of ovarian torsion was suspected after abdominopelvic unenhanced computed tomography and ultrasound revealed a large cyst in contact with the bladder,ovary,and *** patient underwent emergency laparotomy per-formed by gynecologists,but it was discovered that the cystic tumor originated from the *** surgeons were then called in to perform a *** examination confirmed the diagnosis of cystic lymphangioma of the *** patient had an uneventful postoperative *** Mesenteric lymphangiomas can cause abdominal pain,and imaging techniques can help determine their characteristics,location,and *** surgical excision and pathological examination are considered the standard treatment and diagnostic method.

关键词： Rupture Jejunum Mesenteric cystic lymphangioma Ovarian torsion Surgical excision Pathological examination Case report