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Strength and damage evolution mechanism of rock mass with holes under cyclic loading

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Journal of Central South University 2024年第8期31卷 2717-2735页

作者： LIU Hong-tao han zi-jun GUO Xiao-fei LIU Qin-yu QIAO Zhong-jin LIANG Jia-lu CHENG Wen-cong ZhanG Xi-ying ZhanG Yu-qi School of Energy and Mining Engineering China University of Mining and Technology(Beijing)Beijing 100083China Research Center of Roadway Support and Surrounding Rock Control Engineering in Coal Industry Beijing 100083China

The damage and failure law of rock mass with holes is of great significance to the stability control of roadways. This study investigates the mechanical properties and failure modes of porous rock masses under cyclic loading, elucidates the acoustic emission (AE) characteristics and their spatial evolution, and establishes the interrelation among AE, stress, strain, time, and cumulative damage. The results reveal that the rock mass with holes and the intact rock mass show softening and hardening characteristics after cyclic loading. The plastic strain of the rock mass with holes is smaller than that of the intact rock mass, and the stress −strain curve shows hysteresis characteristics. Under uniaxial compression, the pore-bearing rock mass shows the characteristics of higher ringing count, AE energy, b-value peak, and more cumulative ringing count in the failure stage, while it shows lower characteristics under cyclic action. At the initial stage of loading, compared with the intact rock mass, the pore-containing rock mass shows the characteristics of a low b-value. The AE positioning and cumulative damage percentage are larger, and the AE positioning is denser around the hole. The specimen with holes is mainly shear failure, and the complete specimen is mainly tensile shear failure.

关键词： roadway surrounding rock control acoustic emission cyclic loading failure mode precursor of destruction

Asymptotic Inference in the Random Coefficient Autoregressive Model with Time-functional Variance Noises

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 320-346页

作者： En-wen ZHU zi-wei DENG han-jun ZhanG jun CAO Xiao-hui LIU Department of Mathematics and Statistics Changsha University of Science and TechnologyChangsha 410114China School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105China School of Statistics and Data Science and Key Laboratory of Data Science in Finance and EconomicsJiangxi University of Finance and EconomicsNanchang 330013China

This paper considers the random coefficient autoregressive model with time-functional variance noises,hereafter the RCA-TFV *** first establish the consistency and asymptotic normality of the conditional least squares estimator for the constant *** semiparametric least squares estimator for the variance of the random coefficient and the nonparametric estimator for the variance function are constructed,and their asymptotic results are reported.A simulation study is presented along with an analysis of real data to assess the performance of our method in finite samples.

关键词： random coefficient autoregressive model time-functional variance conditional least squares semiparametric least squares

A Fluorine-Functionalized 3D Covalent Organic Framework with Entangled 2D Layers

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Chinese Journal of Polymer Science 2024年第8期42卷 1210-1216页

作者： Li-Bang Xiao zi-han Wu jun-Jie Xin Yuan-Peng Cheng Bo Gui jun-Liang Sun Cheng Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China College of Chemistry and Molecular Engineering Beijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871China

Constructing three dimensional(3D)covalent organic frameworks(COFs)through the entanglement of two dimensional(2D)nets is a promising but underdeveloped ***,we report the design and synthesis of a fluorine functionalized 3DCOF(3D-An-COF-F)formed by entangled 2D sql *** structure of 3D-An-COF-F was determined by the combination of continuous rotation electron diffraction technique and modelling based on the chemical information from real ***,compared to the isostructural 3D-An-COF without F atom s,3DAn-COF-F showed an improved CO_(2)sorption ability and higher CO_(2)/N_(2)*** study not only demonstrated the generality of constructing 3D COFs with entangled 2D nets by introducing bulky groups vertically in planar building blocks,but also will expand the diversity of 3D COFs for various applications.

关键词： 3D covalent organic frameworks Fluorine Entangled 2D layers Electron diffraction CO_(2)adsorption

Thermodynamic and experimental study of high-temperature roasting of blast furnace gas ash for recovery of metallic zinc and iron

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Journal of Iron and Steel Research International 2024年第1期31卷 108-120页

作者： zi-han Wang Jing Guo han-jie Guo Bin Li School of Metallurgical Engineering University of Science and Technology BeijingBeijing100083China School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina

A high-temperature reduction roasting method was used to achieve metallic iron and zinc recovery from blast furnace gas ash(BFA).The reduction processes for Zn-containing and Fe-containing oxides were analyzed in detail by using ther-modynamic equilibrium calculation and the principle of minimum free *** results showed that the main reaction in the system is the reduction of ZnFe_(2)_(4)and iron *** the full temperature range,iron oxides were more easily reduced than zinc *** of the amount of CO contained in the system,the reduction of ZnO to Zn was difficult to proceed below the boiling point(906℃)of *** the reduction temperature is below 906℃,the reduction process of zinc ferrate was ZnFe_(2)_(4)→ZnO;when the reduction temperature is above 906℃,its reduction process becomed ZnFe_(2)_(4)→ZnO→Zn(g).The metallization and dezincification rates of the BFA gradually increased with increasing reaction *** the C/O ratio increased,the metallization and dezincification rates first increased and then *** effect of reduction time on BFA reduction was similar to that of reaction temperature.

关键词： Blast furnace gas ash Thermodynamics zinc removal Iron reduction High-temperature reduction roasting Integrated utilization

An Interpolation Method for Karhunen-Loève Expansion of Random Field Discretization

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工程与科学中的计算机建模(英文) 2024年第1期138卷 245-272页

作者： zi han Zhentian Huang Department of Engineering Mechanics Hohai UniversityNanjing211100China College of Civil and Transportation Engineering Shenzhen UniversityGuangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and UtilizationInstitute of Deep Earth Sciences and Green EnergyShenzhenChina

In the context of global mean square error concerning the number of random variables in the representation,the Karhunen–Loève(KL)expansion is the optimal series expansion method for random field *** computational efficiency and accuracy of the KL expansion are contingent upon the accurate resolution of the Fredholm integral eigenvalue problem(IEVP).The paper proposes an interpolation method based on different interpolation basis functions such as moving least squares(MLS),least squares(LS),and finite element method(FEM)to solve the *** with the Galerkin method based on finite element or Legendre polynomials,the main advantage of the interpolation method is that,in the calculation of eigenvalues and eigenfunctions in one-dimensional random fields,the integral matrix containing covariance function only requires a single integral,which is less than a two-folded integral by the Galerkin *** effectiveness and computational efficiency of the proposed interpolation method are verified through various one-dimensional ***,based on theKL expansion and polynomial chaos expansion,the stochastic analysis of two-dimensional regular and irregular domains is conducted,and the basis function of the extended finite element method(XFEM)is introduced as the interpolation basis function in two-dimensional irregular domains to solve the IEVP.

关键词： Random field discretization KL expansion IEVP MLS FEM stochastic analysis

Turning point of organoid transplantation:first-in-human trial of iPSC-derived retinal organoid grafting in patients with retinitis pigmentosa

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Science China(Life Sciences) 2024年第5期67卷 1082-1084页

作者： Chang-jun Zhang zi-Bing Jin Beijing Institute of Ophthalmology Beijing Tongren HospitalCapital Medical UniversityBeijing 100730China

The discovery of induced pluripotent stem cells(iPSCs)has revolutionized the field of disease research,providing a promising platform for studying various *** the last decade,significant progress has been made in combining iPSCs with other cutting-edge technologies to investigate disease mechanisms and develop potential treatments.

关键词： conditions patients retinitis

Safflower Yellow Inhibits Progression of Hepatocellular Carcinoma by Modulating Immunological Tolerance via FAK Pathway

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Chinese Journal of Integrative Medicine 2024年第4期30卷 339-347页

作者： JI Hua-feng YANG zi-qiang han jun-jun LI He-fang JIN Zhao-qing CHEN Wei-qing CHEN Fei-hua GONG Mou-chun Department of General Surgery First People's Hospital of Hangzhou Lin'an DistrictHangzhou(311300)China

Objective To explore the anti-tumor effect of safflower yellow(SY)against hepatocellular carcinoma(HCC)and the underlying potential *** An in vitro model was established by mixing Luc-Hepa1-6 cells and CD3^(+)CD8^(+)T cells,followed by adding programmed cell death protein 1(PD-1)antibody(Anti-mPD-1)with or without *** apoptosis was detected by flow cytometry and the level of inflammatory cytokines was determined by enzyme-linked immunosorbent *** protein levels of programmed cell death 1 ligand 1(PD-L1),chemokine ligand(CCL5),C-X-C motif chemokine ligand 10(CXCL10)were measured by Western *** in situ animal model was established in mice followed by treatment with anti-mPD-1 with or without *** imaging was monitored with an AniView 100 imaging *** establish the FAK-overexpressed Luc-Hepa1-6 cells,cells were transfected with adenovirus containing pcDNA3.1-FAK for 48 *** The fluorescence intensity,apoptotic rate,release of inflammatory cytokines,and CCL5/CXCL10 secretion were dramatically facilitated by anti-mPD-1(Phanced by SY(Phanced by SY(Phanced effects of SY on inhibiting tumor cell growth,facilitating apoptosis and inflammatory cytokine releasing,suppressing the PD-1/PD-L1 axis,and inducing the CCL5/CXCL10 secretion in Anti-mPD-1 treated mixture of Luc-Hepa1-6 cells and CD3+CD8+T cells were abolished by FAK overexpression(P<0.01).Conclusion SY inhibited the progression of HCC by mediating immunological tolerance through inhibiting FAK.

关键词： hepatocellular carcinoma safflower yellow Chinese medicine tumor microenvironment programmed cell death protein 1 focal adhesion kinase

A Multi-Stage Differential-Multifactorial Evolutionary Algorithm for Ingredient Optimization in the Copper Industry

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2135-2153页

作者： Xuerui Zhang Zhongyang han jun Zhao School of Control Science and Engineering Dalian University of TechnologyDalian 116024China IEEE

Ingredient optimization plays a pivotal role in the copper industry,for which it is closely related to the concentrate utilization rate,stability of furnace conditions,and the quality of copper *** acquire a practical ingredient plan,which should exhibit long duration time with sufficient utilization and feeding stability for real applications,an ingredient plan optimization model is proposed in this study to effectively guarantee continuous production and stable furnace *** address the complex challenges posed by this integer programming model,including multiple coupling feeding stages,intricate constraints,and significant non-linearity,a multi-stage differential-multifactorial evolution algorithm is *** the proposed algorithm,the differential evolutionary(DE)algorithm is improved in three aspects to efficiently tackle challenges when optimizing the proposed ***,unlike traditional time-consuming serial approaches,the multifactorial evolutionary algorithm is utilized to optimize multiple complex models contained in the population of evolutionary algorithm caused by the feeding stability in a parallel ***,a repair algorithm is employed to adjust infeasible ingredient lists in a timely *** addition,a local search strategy taking feedback from the current optima and considering the different positions of global optimum is developed to avoiding premature convergence of the differential evolutionary ***,the simulation experiments considering different planning horizons using real data from the copper industry in China are conducted,which demonstrates the superiority of the proposed method on feeding duration and stability compared with other commonly deployed *** is practically helpful for reducing material cost as well as increasing production profit for the copper industry.

关键词： Copper industry differential-multifactorial evolution ingredient optimization multi-stage optimization

Identification and validation of a new prognostic signature based on cancer-associated fibroblast-driven genes in breast cancer

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World Journal of Clinical Cases 2024年第4期12卷 700-720页

作者： zi-Zheng Wu Yuan-jun Wei Tong Li Jie Zheng Yin-Feng Liu Meng han Diagnosis and Treatment Center The First Hospital of QinhuangdaoQinhuangdao 066000Hebei ProvinceChina Department of General Surgery Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Breast Disease Diagnosis and Treatment Center The First Hospital of QinhuangdaoHebei Medical UniversityQinhuangdao 066000Hebei ProvinceChina Breast Disease Diagnosis and Treatment Center Chengde Medical CollegeChengde 067000Hebei ProvinceChina

BACKGROUND Breast cancer(BC),a leading malignant disease,affects women all over the *** associated fibroblasts(CAFs)stimulate epithelial-mesenchymal transition,and induce chemoresistance and *** To establish a CAFs-associated prognostic signature to improve BC patient out-come *** We retrieved the transcript profile and clinical data of 1072 BC samples from The Cancer Genome Atlas(TCGA)databases,and 3661 BC samples from the The Gene Expression *** and immune cell infiltrations were quantified using CIBERSORT ***-associated gene identification was done by weighted gene co-expression network analysis.A CAF risk signature was established via univariate,least absolute shrinkage and selection operator regression,and mul-tivariate Cox regression *** receiver operating characteristic(ROC)and Kaplan-Meier curves were employed to evaluate the predictability of the ***,a nomogram was developed with the risk score and patient clinical *** Spearman's correlations analysis,the relationship between CAF risk score and gene set enrichment scores were *** samples were collected to validate gene expression by quantitative real-time polymerase chain reaction(qRT-PCR).RESULTS Employing an 8-gene(IL18,MYD88,GLIPR1,TNN,BHLHE41,DNAJB5,FKBP14,and XG)signature,we attemp-ted to estimate BC patient *** on our analysis,high-risk patients exhibited worse outcomes than low-risk *** analysis revealed the risk score as an independent indicator of BC patient *** analysis exhibited satisfactory nomogram *** area under the curve showed 0.805 at 3 years,and 0.801 at 5 years in the TCGA *** also demonstrated that a reduced CAF risk score was strongly associated with enhanced chemotherapeutic *** risk score was significantly correlated with most hallmark gene ***,the prognostic signature were further validated by qRT-

关键词： Breast cancer Prognosis Gene signature The Cancer Genome Atlas The Gene Expression Omnibus