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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1392-1405页

作者： Liangliang Yuan Mingxing guo Yi wang Yun wang Linzhong Zhuang Institute of Effectiveness Evaluation of Flying Vehicle Beijing 100085China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

This study investigated the influence of graded Zn content on the evolution of precipitated and iron-rich phases and grain struc-ture of the alloys,designed and developed the Al–8.0Zn–1.5Mg–1.5Cu–0.2Fe(wt%)alloy with high strength and *** the increase of Zn content,forming the coupling distribution of multiscale precipitates and iron-rich phases with a reasonable matching ratio and dispersion distribution characteristics is *** phenomenon induces the formation of cell-like structures with alternate distribu-tion of coarse and fine grains,and the average plasticity–strain ratio(characterizing the formability)of the pre-aged alloy with a high strength is up to *** reveal the evolution and influence mechanisms of multiscale second-phase particles and the corresponding high formability mechanism of the *** developed coupling control process exhibits considerable potential,revealing remarkable improvements in the room temperature formability of high-strength Al–Zn–Mg–Cu alloys.

关键词： Al–Zn–Mg–Cu alloy iron-rich phase high formability microstructure mechanisms

Experimental and numerical study regarding H-steel all-bolted connection steel frame with composite wall boards

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 427-443页

作者： Fan Min guo Hongchao Li Shen wang Zhenshan wang Huaqiang School of Civil Engineering and Architecture Xi’an University of TechnologyXi’an 710048China State Key Laboratory Base of Eco-Hydraulic Engineering in Arid Area Xi’an University of TechnologyXi’an 710048China

H-steel all-bolted connection steel frame structures with heat preservation and decoration composite wall boards were investigated and the seismic performances of three scaled specimens were *** failure modes,hysteresis curves,bearing capacity,ductility,energy dissipation capacity,stiffness degradation and strain distribution were *** calculation method of structural theoretical internal force was *** results showed that the overall structural seismic performance was better,and the structural ductility met the demands of elastic-plastic inter-story drift angle for seismic *** H-steel weak-axis connection structure obtained better energy dissipation capacity,and its bearing capacity and stiffness were slightly different from the strong-axis *** heat preservation and decoration performance of composite wallboard and the all-bolted connection of the steel frame realized prefabrication during the whole construction *** plastic hinge of the steel beam can be moved outwards because of the L-angles,which effectively avoids stress concentration in joint areas and expands the plastic hinge *** errors between the theoretical structural capacity calculated by the plastic analysis method and the test results were within 2.44%.In addition,structural failure mechanisms and bearing capacities were verified by the finite element(FE)analysis,and the effects of the main parameters on the structures were *** FE verification results were the same as in the *** research results provide theoretical support and technical guidance for the application of thermal insulation and decorative composite wall panels in H-shaped steel all-bolted steel frames.

关键词： composite wall boards all-bolted steel frame H-steel low-cyclic loading failure modes

Cr-catalyzed allylic C(sp^(3))–H addition to aldehydes enabled by photoinduced ligand-to-metal charge transfer

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Science China Chemistry 2024年第5期67卷 1589-1595页

作者： Xianrong Zeng Feng-Hua Zhang Runchen lai Xiaoyu Lin Zhaobin wang Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Instrumentation and Service Center for Molecular SciencesWestlake UniversityHangzhou 310024China

Photoinduced ligand-to-metal charge transfer(LMCT) has emerged as an effective strategy for synthesizing organic molecules in a sustainable manner. However, the majority of existing reports on selective C(sp^(3))–H bond functionalization via photoinduced LMCT focus on the use of late transition metals or rare-earth metals for radical additions or cross-couplings. In contrast, the utilization of photoinduced LMCT with 3d early transition metals poses a significant challenge. Herein, we describe an unprecedented approach to allylic C(sp^(3))–H addition to aldehydes, employing chromium(Cr) complexes as catalysts through visible-light-induced LMCT. By investigating the reaction pathway through various mechanistic studies, including radical trapping, kinetic isotope effect(KIE) analysis, and transient absorption spectroscopy, valuable insights have been gained. The proposed mechanism suggests the intermediacy of bromine radicals through homolysis of the Cr–Br bond. Notably, this protocol expands our understanding of the photochemical properties of earth-abundant Cr complexes.

关键词： Cr catalysis photoinduced ligand-to-metal charge transfer hydrogen-atom transfer carbonyl addition

Characteristics and stability of oxide+carbonitride in H13 steel at 1250℃

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Journal of Iron and Steel Research International 2024年第1期31卷 134-142页

作者： Xiao-lin Sun Han-jie guo Jing guo Fei wang Dong Xu Gao-yang Song Shuai wang School of Materials Science and Engineering Hebei University of EngineeringHandan056038HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China High Temperature Materials Research Institute Central Iron and Steel Research Institute Co.Ltd.Beijing100081China Technology Innovation Center for High Quality Cold Heading Steel of Hebei Province Hebei University of EngineeringHandan056038HebeiChina

The morphology,size,quantity,and composition of complex oxide+carbonitride in H13 steel held at 1250℃for 5,10,and 15 h were *** results show that the ratio and number of complex carbonitrides with cores in H13 steel are gradually increased when holding at 1250℃compared with those in the original H13 steel,and the core size *** are one or more oxide cores in(Ti_(x),V_(1-x))(Cy,N_(1-y)),including xCaO·zAl_(2)O_(3),xCaO·yMgO·zAl_(2)O_(3),and CaO after holding at 1250℃,in addition to MgO·Al_(2)O_(3)and Al_(2)O_(3)in the original *** equilibrium temperature for(Ti_(x),V_(1-x))(Cy,N_(1-y))precipitation at the solidification front and decomposition in the solid state was theoretically analyzed,which was affected by the x value and the product of Ti and N contents in H13 ***,the composition of(Ti_(x),V_(1-x))(Cy,N_(1-y))is influenced by the oxide *** is convinced that(Ti_(x),V_(1-x))(Cy,N_(1-y))with oxide cores has a higher stability,especially for oxides with a high Al_(2)O_(3)*** treatment at high temperature facilitates a more reasonable analysis of oxide+carbonitride,and the generation mechanism of oxide+carbonitride was discussed.

关键词： Complex carbonitride Decomposition Oxide core Characteristic Stability

A Local Tb Theorem for Square Functions and Parabolic Layer Potentials

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1941-1966页

作者： Zhi Dan wang guo Ming ZHANG School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816P.R.China Frontiers Science Center for Nonlinear Expectations Ministry of EductionResearch Center for Mathematics and Interdisciplinary SciencesShandong UniversityQingdao266237P.R.China

In this paper,we give a locally parabolic version of Tb theorem for a class of vector-valued operators with off-diagonal decay in L^(2) and certain quasi-orthogonality on a subspace of L^(2),in which the testing functions themselves are also *** an application,we establish the boundedness of layer potentials related to parabolic operators in divergence form,defined in the upper half-space Rn+2+:={(x,t,λ)∈R^(n+1)×(0,∞)},with uniformly complex elliptic,L^(∞),t,λ-independent coefficients,and satisfying the De Giorgi/Nash estimates.

关键词： Local Tb theorems Calderon-Littlewood-Paley family Parabolic layer potentials Carleson measure estimates

Integrated wellbore-reservoir-geomechanics modeling for enhanced interpretation of distributed fiber-optic strain sensing data in hydraulicfracture analysis

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3136-3148页

作者： Lijun Liu Xinglin guo Xiaoguang wang State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China Tianfu Yongxing Laboratory Chengdu610213China College of Energy Chengdu University of TechnologyChengdu610059China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu610059China

Fiber-optic distributed strain sensing(FO-DSS)has been successful in monitoring strain changes along horizontal wellbores in hydraulically fractured ***,the mechanism driving the various FO-DSS responses associated with near-wellbore hydraulic fracture properties is still *** address this knowledge gap,we use coupled wellbore-reservoir-geomechanics simulations to study measured strain-change behavior and infer hydraulic fracture *** crossflow among fractures is captured through explicit modeling of the transient wellbore *** addition,local grid refinement is applied to accurately capture strain changes along the fiber.A Base Case model was designed with four fractures of varying properties,simulating strain change signals when the production well is shut-in for 10 d after 240 d of production and reopened for 2 ***-pressure plots for different fracture clusters were used to gain insights into inferring fracture properties using DSS *** comparing the model with and without the wellbore,distinct strain change signals were observed,emphasizing the importance of incorporating the wellbore in FO-DSS *** effects of fracture spacing and matrix permeability on strain change signals were thoroughly *** results of our numerical study can improve the understanding of the relation between DSS signals and fracture hydraulic properties,thus maximizing the value of the dataset for fracture diagnostics and characterization.

关键词： Distributed strain sensing Fracture diagnostic Coupled flow and geomechanics Transient wellbore flow

Differentially private SGD with random features

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 1-23页

作者： wang Yi-guang guo Zheng-chu Polytechnic Institute of Zhejiang University Zhejiang UniversityHangzhou 310015China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China

In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization ***,since the collected data may contain some sensitive information,it is also of great significance to study privacy-preserving machine learning *** paper focuses on the performance of the differentially private stochastic gradient descent(SGD)algorithm based on random *** begin,the algorithm maps the original data into a lowdimensional space,thereby avoiding the traditional kernel method for large-scale data storage ***,the algorithm iteratively optimizes parameters using the stochastic gradient descent ***,the output perturbation mechanism is employed to introduce random noise,ensuring algorithmic *** prove that the proposed algorithm satisfies the differential privacy while achieving fast convergence rates under some mild conditions.

关键词： learning theory differential privacy stochastic gradient descent random features reproducing kernel Hilbert spaces

Cooperation between single atom catalyst and support to promote nitrogen electroreduction to ammonia:A theoretical insight

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Journal of Energy Chemistry 2024年第9期96卷 336-344页

作者： Wanying guo Siyao wang Hongxia wang Qinghai Cai Jingxiang Zhao College of Chemistry and Chemical Engineering Harbin Normal UniversityHarbin 150025HeilongjiangChina

The co-catalysis between single atom catalyst(SAC)and its support has recently emerged as a promising strategy to synergistically boost the catalytic activity of some complex electrochemical reactions,encompassing multiple intermediates and ***,we utilized defective BC_(3)monolayer-supported SACs as a prototype to investigate the cooperative effects of SACs and their support on the catalytic performance of the nitrogen reduction reaction(NRR)for ammonia(NH_(3))*** results showed that these SACs can be firmly stabilized on these defective BC_(3)supports with high stability against ***,co-activation of the inert N_(2)reactant was observed in certain embedded SACs and their neighboring B atoms on certain BC3 sheets due to the noticeable charge transfer and significant N–N bond *** high-throughput screening revealed that the Mo/DV_(CC)and W/DV_(CC)exhibit superior NRR catalytic performance,characterized by a low limiting potential of−0.33 and−0.43 V,respectively,which can be further increased under acid conditions based on the constant potential ***,varying NRR catalytic activities can be attributed to the differences in the valence state of active ***,further microkinetic modeling analysis displayed that the turnover frequency of N_(2)–to–NH_(3)conversion on Mo/DV_(CC)is as large as 1.20×10^(−3)s^(−1)site^(−1) at 700 K and 100 bar,thus guaranteeing its ultra-fast reaction *** results not only suggest promising advanced electrocatalysts for NRR but also offer an effective avenue to regulate the electrocatalytic performance via the co-catalytic metal–support interactions.

关键词： Co-catalysis Single atom catalyst Nitrogen reduction DFT computations

Adrenal pheochromocytoma impacts three main pathways: cysteine-methionine, pyrimidine, and tyrosine metabolism

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第5期25卷 410-421页

作者： Chong lai Qingling YANG Yunuo ZHANG Renjie GONG Majie wang Jiankang LI Maode lai Qingrong SUN Department of Urology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China School of Basic Medical Sciences and Clinical Pharmacy China Pharmaceutical UniversityNanjing 210009China Department of Laboratory Medicine the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Laboratory of Behavioral Neuroscience Ningbo Kangning HospitalNingbo Institute of Microcirculation and HenbaneSchool of MedicineNingbo UniversityNingbo 315201China Xi'an Key Laboratory of Stem Celland Regenerative Medicine Institute of Medical ResearchNorthwestern Polytechnical UniversityXi'an 710072China Department of Pathology Research Unit of Intelligence Classification of Tumor Pathology and Precision TherapyChinese Academy of Medical Sciences Key Laboratory of Disease Proteomics of Zhejiang ProvinceZhejiang University School of MedicineHangzhou 310058China

Pheochromocytomas and paragangliomas(PPGLs)cause symptoms by altering the circulation levels of catecholamines and peptide ***,the diagnosis of PPGLs relies on diagnostic imaging and the detection of *** this study,we used ultra-performance liquid chromatography(UPLC)/quadrupole time-of-flight mass spectrometry(Q-TOF MS)analysis to identify and measure the perioperative differential metabolites in the plasma of adrenal pheochromocytoma *** identified differentially expressed genes by comparing the transcriptomic data of pheochromocytoma with the normal adrenal *** conducting two steps of metabolomics analysis,we identified 111 differential metabolites between the healthy group and the patient group,among which 53 metabolites were *** integrating the information of differential metabolites and differentially expressed genes,we inferred that the cysteine-methionine,pyrimidine,and tyrosine metabolism pathways were the three main metabolic pathways altered by the *** analysis of transcription levels revealed that the tyrosine and cysteine-methionine metabolism pathways were downregulated in pheochromocytoma,whereas the pyrimidine pathway showed no significant ***,we developed an optimized diagnostic model of two metabolites,L-dihydroorotic acid and *** results for these metabolites suggest that they may serve as potential clinical biomarkers and can be used to supplement and improve the diagnosis of pheochromocytoma.

关键词： Pheochromocytoma and paraganglioma(PPGL) Metabolomics Gene set variation analysis L-Dihydroorotic acid Vanylglycol

Genome-wide association with transcriptomics reveals a shade-tolerance gene network in soybean

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The Crop Journal 2024年第1期12卷 232-243页

作者： Yanzhu Su Xiaoshuai Hao Weiying Zeng Zhenguang lai Yongpeng Pan Can wang Pengfei guo Zhipeng Zhang Jianbo He Guangnan Xing Wubin wang Jiaoping Zhang Zudong Sun Junyi Gai Soybean Research Institute/MARA National Center for Soybean Improvement MARA Key Laboratory of Biology and Genetic Improvement of Soybean/State Key Laboratory for Crop Genetics and Germplasm Enhancement/State Innovation Platform for Integrated Production and Education in Soybean Bio-breeding/Jiangsu Collaborative Innovation Center for Modern Crop Production Nanjing Agricultural UniversityNanjing 210095JiangsuChina Guangxi Academy of Agricultural Sciences Nanning 530007GuangxiChina

Shade tolerance is essential for soybeans in inter/relay cropping systems.A genome-wide association study(GWAS)integrated with transcriptome sequencing was performed to identify genes and construct a genetic network governing the trait in a set of recombinant inbred lines derived from two soybean parents with contrasting shade *** improved GWAS procedure,restricted two-stage multi-locus genome-wide association study based on gene/allele sequence markers(GASM-RTM-GWAS),identified 140 genes and their alleles associated with shade-tolerance index(STI),146 with relative pith cell length(RCL),and nine with *** of these genes by biological categories allowed the construction of a protein–protein interaction network by 187 genes,of which half were differentially expressed under shading and non-shading conditions as well as at different growth *** the identified genes,three ones jointly identified for both traits by both GWAS and transcriptome and two genes with maximum links were chosen as beginners for entrance into the ***,both STI and RCL gene systems worked for shade-tolerance with genes interacted each other,this confirmed that shadetolerance is regulated by more than single group of interacted genes,involving multiple biological functions as a gene network.

关键词： Soybean(Glycine max(L.)Merr.) Shade-tolerance Restricted two-stage multi-locus genomewide association study based on gene/allele sequence markers(GASM-RTM-GWAS) Shade-tolerance index(STI) Relative cell length(RCL) Transcriptome