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Reducible solution to a quaternion tensor equation

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Frontiers of Mathematics in China 2020年第5期15卷 1047-1070页

作者： Mengyan XIE qing-wen wang Department of Mathematics Shanghai UniversityShanghai 200444China

We establish necessary and sufficient conditions for the existence of the reducible solution to the quaternion tensor equation A*N C*NB=C via Einstein product using Moore-Penrose inverse,and present an expression of the reducible solution to the equation when it is ***,to have a general solution,we give the solvability conditions for the quaternion tensor equation A1*N C1*MB1+a1*C2*MB2+A2*NC3*MB2=e,which plays a key role in investigating the reducible solution to A*NC*NB=*** expression of such a solution is also presented when the consistency conditions are *** addition,we show a numerical example to illustrate this result.

关键词： Quaternion tensor quaternion tensor equation Einstein product Moore-Penrose inverse general solution reducible solution

Weighted Moore-Penrose Inverses and Weighted Core Inverses in Rings with Involution

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Chinese Annals of Mathematics,Series B 2021年第4期42卷 613-624页

作者： Huihui ZHU qing-wen wang Department of Mathematics Shanghai UniversityShanghai 200444China School of Mathematics Hefei University of TechnologyHefei 230009China

In this paper,the authors derive the existence criteria and the formulae of the weighted Moore-Penrose inverse,the e-core inverse and the f-dual core inverse in ***,new characterizations between weighted Moore-Penrose... 详细信息

关键词： Weighted Moore-Penrose inverses One-sided inverses along an element Inverses along an element e-Core inverses f-Dual core inverses

Ranks of the Common Solution to Six Quaternion Matrix Equations

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Acta Mathematicae Applicatae Sinica 2011年第3期27卷 443-462页

作者： qing-wen wang Yan Zhou Qin Zhang Department of Mathematics Shanghai University 99 Shangda Road Shanghai 200444 China

A new expression is established for the common solution to six classical linear quaternion matrix equations A 1 X = C 1 , X B 1 = C 3 , A 2 X = C 2 , X B 2 = C 4 , A 3 X B 3 = C 5 , A 4 X B 4 = C 6 which was investigated recently by wang, Chang and Ning （Q. wang, H. Chang, Q. Ning, The common solution to six quaternion matrix equations with applications, Appl. Math. Comput. 195： 721-732 （2008））. Formulas are derived for the maximal and minimal ranks of the common solution to this system. Moreover, corresponding results on some special cases are presented. As an application, a necessary and sufficient condition is presented for the invariance of the rank of the general solution to this system. Some known results can be regarded as the special cases of the results in this paper.

关键词： system of matrix equations quaternion matrix minimal rank maximal rank linear matrixexpression generalized inverse

A System of Sylvester-type Quaternion Matrix Equations with Ten Variables

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Acta Mathematica Sinica,English Series 2022年第8期38卷 1399-1420页

作者： Meng Yan XIE qing wen wang Zhuo Heng HE Mehany Mahmoud SAAD Department of Mathematics Shanghai UniversityShanghai 200444P.R.China

This paper studies a system of three Sylvester-type quaternion matrix equations with ten variables A_(i)X_(i)+Y_iB_(i)+C_(i)Z_(i)D_(i)+F_(i)Z_(i+1)G_(i)=E_(i),i=1,3^-.We derive some necessary and sufficient conditions for the existence of a solution to this system in terms of ranks and Moore–Penrose inverses of the matrices *** present the general solution to the system when the solvability conditions are *** applications of this system,we provide some solvability conditions and general solutions to some systems of quaternion matrix equations involvingφ-***,we give some numerical examples to illustrate our *** findings of this paper extend some known results in the literature.

关键词： Quaternion matrix equation φ-Hermitian solution general solution solvability

Research on testing method of resin sand high temperature compressive strength

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China Foundry 2016年第5期13卷 335-341页

作者： Peng Wan Luan-cai Li Long Zhang wen-qing wang State Key Laboratory of Materials Processing and Die & Mould Technology Huazhong University of Science & Technology School of Metallurgical Engineering Anhui University of Technology

High temperature compressive strength is one of the most important performances of resin sand; its value directly concerns the quality of castings. In order to seek the best testing method of resin sand high temperature compressive strength, a self-developed instrument was used to carry out experiments, and the sample shape and size were designed and studied. The results show that a hollow cylinder sample can reflect the strength difference of different resin sands better than a solid cylinder sample, and its data is stable. The experiments selected φ20/5×30 mm as the size of the hollow cylinder samples. The high temperature compressive strengths of phenol-formaldehyde resin coated sand, furan resin self-setting sand, and TEA resin sand were each tested. For the resin sand used for cast steel and cast iron, 1,000 ℃ was selected as the test temperature; for the resin sand used for cast non-ferrous alloy, 800 ℃ was selected as the test temperature; and for all the resin sand samples, 1 min was selected as the holding time. This testing method can truthfully reflect the high temperature performance of three kinds of resin sand; it is reproducible, and the variation coefficients of test values are under 10%.

关键词： resin sand high temperature compressive strength hollow cylinder specimens variation coefficient

Spatial distribution of Cd and Cu in soils in Shenyang Zhangshi Irrigation Area(SZIA),China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第3期9卷 271-278页

作者： Li-na SUN Xiao-bo YANG wen-qing wang Li MA Su CHEN Key Laboratory of Eco-Remediation of Contaminated Environment and Resourcilization Technology Shenyang University Shenyang 110044 China Liaoning Geology Academe Shenyang 110032 China

Heavy metal contamination of soils,derived from sewage irrigation,mining and inappropriate utilization of various agrochemicals and pesticides,and so on,has been of wide concern in the last several *** Shenyang Zhangshi Irrigation Area(SZIA) in China is a representative area of heavy metal contamination of soils resulting from sewage irrigation for about 30 *** study investigated the spatial distribution and temporal variation of soil cadmium(Cd) and copper(Cu) contamination in the *** soil samples were collected from the SZIA in 1990 and 2004;Cd and Cu in soils was analyzed and then the spatial distribution and temporal variation of Cd and Cu in soils were modeled using Kriging *** results show that long-term sewage irrigation had caused serious Cd and Cu contamination in *** mean and the maximum of soil Cd are markedly higher than the levels in second grade standard soil(LSGSS) in China,and the maximum of soil Cu is close to the LSGSS in China in 2004 and is more than the LSGSS in China in *** contamination magnitude of soil Cd and the soil extent of Cd contamination had evidently increased since sewage irrigation ceased in *** contamination magnitude of soil Cu and the soil extent of Cu contamination had evidently increased in topsoil,but obviously decresed in *** soil contamination of Cd and Cu was mainly related to Cd and Cu reactivation of contaminated sediments in Shenyang Xi River and the import of Cd and Cu during *** eluviation of Cd and Cu in contaminated topsoil with rainfall and irrigation water was another factor of temporal-spatial variability of Cd and Cu contamination in soils.

关键词： Cadmium (Cd) Copper (Cu) Contamination of soils Spatial distribution Shenyang Zhangshi Irrigation Area (SZLA)

Cascade electrolysis and thermocatalysis: a reliable system for upgrading C1 to C4 hydrocarbons

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Rare Metals 2024年第1期43卷 410-412页

作者： Chao-Yue Sun wen Li Hai-qing wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China

The carbon cycle is important for maintaining a stable climate and carbon balance on Earth. Renewable-electricitydriven upcycling of carbon dioxide (CO_(2)) into value-added multi-carbon molecules is a potentially sus... 详细信息

关键词： cycling hydrocarbons enable

Dynamic changes in the systemic immune responses of spinal cord injury model mice

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Neural Regeneration Research 2021年第2期16卷 382-387页

作者： Tian-Yun Gao Fei-Fei Huang Yuan-Yuan Xie wen-qing wang Liu-Di wang Dan Mu Yi Cui Bin wang Clinical Stem Cell Center the Affiliated Drum Tower Hospital of Nanjing University Medical SchoolNanjingJiangsu ProvinceChina Department of Radiology the Affiliated Drum Tower Hospital of Nanjing University Medical SchoolNanjingJiangsu ProvinceChina Reproductive and Genetic Center of National Research Institute for Family Planning BeijingChina

Intraspinal inflammatory and immune responses are considered to play central roles in the pathological development of spinal cord *** study aimed to decipher the dynamics of systemic immune responses,initiated by spinal cord *** spinal cord in mice was completely transected at *** in the in vivo inflammatory response,between the acute and subacute stages,were observed.A rapid decrease in C-reactive protein levels,circulating leukocytes and lymphocytes,spleen-derived CD4~+interferon-γ+T-helper cells,and inflammatory cytokines,and a marked increase in neutrophils,monocytes,and CD4~+CD25~+FOXP3~+regulatory T-cells were observed during the acute *** systemic immune alterations were gradually restored to basal levels during the sub-acute *** the acute phase of spinal cord injury,systemic immune cells and factors showed significant inhibition;however,this inhibition was transient,and the indicators of these serious disorders gradually returned to baseline levels during the subacute *** experiments were performed in accordance with the institutional animal care guidelines,approved by the Institutional Animal Care and Use Committee of Experimental Animal Center of Drum Tower Hospital,China(approval No.2019 AE01040)on June 25,2019.

关键词： C-reactive protein immune dysfunction inflammation inflammatory cytokines regulatory T-cells spinal cord injury systemic immune response T-helper cells

Cut-off value of glycated hemoglobin A1c for detecting diabetic retinopathy in the Chinese population

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World Journal of Diabetes 2024年第7期15卷 1531-1536页

作者： Yan wen qing wang Department of Endocrinology China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina

BACKGROUND Glycated hemoglobin A1c(HbA1c)is considered the most suitable for diabetes mellitus diagnosis due to its accuracy and ***,the effect of HbA1c on diabetic retinopathy(DR)in the Han and Korean populations in Jilin,China,remains *** To determine the best cut-off of HbA1c for diagnosing DR among the *** This cross-sectional study included 1933 participants from the Yanbian area of Jilin Province,*** investigators employed a questionnaire-based survey,physical examination,laboratory tests,and fundus photography for the *** best cut-off value for HbA1c was established via the receiver operating characteristic *** factors associated with HbA1c-associated risk factors were determined via linear *** The analysis included 887 eligible Chinese Han and Korean participants,591 of whom were assigned randomly to the training set and 296 to the validation *** prevalence of DR was 3.27% in the total ***1c of 6.2% was the best cut-off value in the training set,while it was 5.9% in the validation *** both Chinese Han and Korean populations,an HbA1c level of 6.2% was the best cut-off *** optimal cut-off values of fasting blood glucose(FBG)≥7 mmol/L and<7 mmol/L were 8.1% and 6.2% respectively in Han populations,while those in Korean populations were 6.9%and 5.3%,***,body mass index,and FBG were determined as the risk factors impacting HbA1c *** HbA1c may serve as a useful diagnostic indicator for *** HbA1c level of 6.2% may be an appropriate cut-off value for DR detection in the Chinese population.

关键词： Diabetic retinopathy Glycated hemoglobin A1c Cut-off value Age Body mass index Fasting blood glucose