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Design of platinum single-atom doped metal nanoclusters as efficient oxygen reduction electrocatalysts by coupling electronic descriptor

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Nano Research 2022年第8期15卷 7016-7025页

作者： Qing Liu Xiaoxu Wang Lu Li Keke Song ping qian Yuan ping Feng Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Department of Physics Faculty of ScienceNational University of SingaporeSingapore 117551Singapore DP Technology Beijing 100080China

Inspired by the single-atom catalysts(SACs)concept,we rationally design a series of Pt single atom catalysts embedded in different transition metal nanoclusters through first-principles *** these so-called“crown-jewel”(CJ)structures,Pt atoms(jewels)occupy the vertex sites of the metal nanocluster(crown)*** investigated the thermal stability and oxygen reduction reaction(ORR)catalytic activity of these *** results reveal that CJ-structured PtCu nanoclusters are stable and possess a comparable or even better ORR activity compared to Pt catalyst,making it a promising candidate for low-cost ORR *** effect of cluster size on the adsorption strength of ORR intermediates and catalytic property has also been ***,the overall ORR catalytic activity trend of these SACs is explained based on analysis of their electronic properties.A descriptorΨwas established to provide further insight into the correlation between the electronic structure and catalytic activity,which provides a design strategy for new ORR *** importantly,we reveal that this electronic descriptor can be extended to predict other CJ-structured nanoclusters.

关键词： single-atom catalysts crown-jewel oxygen reduction reaction(ORR) catalyst design nanocluster

Lie Point Symmetries and Exact Solutions of Couple KdV Equations

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Communications in Theoretical Physics 2007年第4期47卷 582-586页

The simple Lie point symmetry reduction procedure is used to obtain infinitely many symmetries to a new integrable system of coupled KdV equations. Using some symmetry subalgebra of the equations, five types of the significant similarity reductions are obtained by virtue of the Lie group approach, and obtain abundant solutions of the coupled KdV equations, such as the solitary wave solution, exponential solution, rational solution, polynomial solution, etc.

关键词： coupled KdV equations Lie point symmetry exact solutions

Optimal Design of Multiple Stress Constant Accelerated Life Test Plan on Non-rectangle Test Region

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1231-1237页

作者： CHEN Wenhua GAO Liang LIU Juan qian ping PAN Jun Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China Zhejiang Province's Key Laboratory for Reliability Technology of Mechanical & Electrical Products Zhejiang Sci-Tech University Hangzhou 310018 China

For optimal design of constant stress accelerated life test（CSALT） with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT design on non-rectangle test region, the present method is only focused on non-rectangle test region with simple boundary, and the optimization algorithm is based on experience which can not ensure to obtain the optimal plan. In this paper, considering the linear-extreme value model and the optimization goal to minimize the variance of lifetime estimate under normal stress, the optimal design method of two-stress type-I censored CSALT plan on general non-rectangular test region is proposed. First, two properties of optimal test plans are proved and the relationship of all the optimal test plans is determined analytically. Then, on the basis of the two properties, the optimal problem is simplified and the optimal design method of two-stress CSALT plan on general non-rectangular test region is proposed. Finally, a numerical example is used to illustrate the feasibility and effectiveness of the method, The result shows that the proposed method could obtain the optimal test plan on non-rectangular test regions with arbitrary boundaries. This research provides the theory and method for two-stress optimal CSALT planning on non-rectangular test regions.

关键词： accelerated life test non- rectangular test region test plan optimal design

Optimal Design of Multiple Stresses Accelerated Life Test Plan Based on Transforming the Multiple Stresses to Single Stress

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Chinese Journal of Mechanical Engineering 2014年第6期27卷 1125-1132页

作者： GAO Liang CHEN Wenhua qian ping PAN Jun HE Qingchuan College of Mechanical and Electrical Engineering Sichuan Agricultural University Zhejiang Province's Key Laboratory for Reliability Technology of Mechanical & Electrical Products Zhejiang Sci-Tech University

For planning optimum multiple stresses accelerated life test plans, a commonly followed guiding principle is that all parameters of the life-stress relationship should be estimated, and the number of the stress level combinations must be no less than the number of parameters of the life-stress relationship. However, the general objective of an accelerated life test（ALT） is to assess thep-th quantile of the product life distribution under normal stress. For this objective,estimating all model parameters is not necessary, and this will increase the cost of test. Based on the theoretical conclusion that the stress level combinations of the optimum multiple stresses ALT plan locate on a straight line through the origin of coordinate, it is proposed that a design idea of planning the optimum multiple stresses ALT plan through transforming the problem of designing an optimum multiple stresses ALT plan to designing an optimum single stress ALT plan. Moreover, a method of planning the optimum multiple stresses ALT plan which can avoid estimating all model parameters is established. An example shows that, the proposed plan which only has two stress level combinations could achieve an accuracy no less than the traditional plan, and save the test time and cost on one stress level combination at least; when the actual product life is less than the design value, even the deviation of the model initial parameters value is up to 20%, the variance of the estimation of thep-th quantile of the proposed plan is still smaller than the traditional plans approximately 25%. A design method is provided for planning the optimum multiple stresses ALT which uses the statistical optimum degenerate test plan as the optimum multiple stresses accelerated life test plan.

关键词： multiple stresses accelerated testing optimum design test planning

Survivin:Potential role in diagnosis,prognosis and targeted therapy of gastric cancer

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World Journal of Gastroenterology 2007年第20期13卷 2784-2790页

作者： Ting-Ting Wang Xiao-ping qian Bao-Rui Liu (Department of Oncology Affiliated Gulou Hospital Medical School of Nanjing University Nanjing 210008 Jiangsu Province China )

Survivin is a protein that is highly expressed in a vast number of malignancies,but is minimally expressed in normal tissues. It plays a role as an inhibitor of cell death in cancer cells,thus facilitating the growth of these cells. In the case of gastric cancer,survivin is over-expressed in tumor cells and plays a role in the carcinogenesis process. Several studies on gastric cancer have indicated that there is a relationship between survivin expression and the ultimate behavior of the carcinoma. Since the expression pattern of survivin is selective to cancer cells,it has been described as an "ideal target" for cancer therapy. Currently,several pre-clinical and clinical trials are on-going to investigate the effects of interfering with survivin function in cancer cells as a biologic therapy. Survivin is a potentially significant protein in the diagnosis,prognosis and treatment of gastric tumors.

关键词： Survivin Gastric neoplasm Diagnosis Prognosis Targeted therapy

Relationship between testosterone and indexes indicating endothelial function in male coronary heart disease patients

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Asian Journal of Andrology 2008年第2期10卷 214-218页

作者： Lu Fu qian-ping Gao Jing-Xia Shen Cardiovascular Department the First Affiliated Hospital of Harbin Medical University Harbin 150001 China

Aim： To investigate the relationship between androgen level and the indexes indicating endothelial function in male patients with coronary heart disease （CHD）. Methods： We registered the following data for 106 50-70-year-old men： age, weight, blood lipid, including total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol and triglyceride, whether a smoker, sugar levels, blood pressure, free testosterone （FT）, vascular cell adhesion molecule- 1 （VCAM- 1） and the intima-media thickness （IMT） of common carotid artery, common carotid diameter, maximum velocity in systolic phase, minimum velocity in diastolic phase and resistent index. Among the 106 men, 51 were patients with CHD. The relationships between FT level, VCAM-1 concentration and IMT were examined, respectively, using a stepwise linear regression technique among all the 106 men. Results： There was no statistical difference in terms of age, blood pressure, whether a smoker, sugar levels, HDL-C, minimum velocity in diastolic phase, resistent index between male CHD patients and controls; whereas results for weight, total cholesterol, low density lipoprotein cholesterol, triglyceride, VCAM- 1 and IMT of male CHD patients were higher than those of controls; FT level and maximum velocity in systolic phase were lower. It was found that among all the objects, FT level was inversely correlated with IMT and VCAM-1 concentration. Condusion： FT level was inversely correlated with VCAM-I concentration and IMT which are indicators of endothelial function. （Asian JAndro12008 Mar; 10： 214-218）

关键词： testosterone coronary heart disease endothelial function

Novel Accelerating Life Test Method and Its Application by Combining Constan Stress and Progressive Stress

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 17-24页

作者： Wen-Hua Chen Fan Yang ping qian Jun Pan Qing-Chuan He Zhejiang Province's Key Laboratory of Reliability Technology for Mechanical and Electronic Product Zhejiang Sci-Tech University School of Engineering Huzhou University

Constant stress accelerated life tests(ALTs) can be applied to obtain a high estimation accuracy of reliability measure?ments, but these are time?consuming tests. Progressive stress ALTs can yield failures more quickly but cannot guaran tee the estimation accuracy of reliability measurements. In this paper, a progressive?constant combination stress ALT is proposed to combine the merits of both tests. The optimal plan, in which the design variables are the initial pro?gressive stress level, the progressive stress ramp rate, the sample allocation proportion of the progressive stress and the constant stress level, is determined using the principle of minimizing the asymptotic variance of the maximum likelihood estimator of the natural log reliable life for the connectors. A comparison between the optimal PCCSALT plan and the CSALT plan with the same sample size and estimation accuracy shows that the test time is reduced by 13.59% by applying the PCCSALT.

关键词： Constant stress Progressive stress Accelerated life test Optimal test plan Reliability test

Design of Accelerated Life Test Plans——Overview and Prospect

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 19-33页

作者： Wen-Hua Chen Liang Gao Jun Pan ping qian Qing-Chuan He Key Laboratory of Reliability Technology for Mechanical and Electrical Product of Zhejiang Province Zhejiang Sci-Tech University College of Mechanical and Electrical Engineering Sichuan Agricultural University

Accelerated life test(ALT) is currently the main method of assessing product reliability rapidly, and the design of efficient test plans is a critical step to ensure that ALTs can assess the product reliability accurately, quickly, and economically. With the promotion of the national strategy of civil-military integration, ALT will be widely used in the research and development(R&D) of various types of products, and the ALT plan design theory will face further challenges. To aid engineers in selecting appropriate theories and to stimulate researchers to develop the theories required in engineering, with focus on the demands for theory research that arise from the implementation of ALT, this paper reviews and summarizes the development of ALT plan design theory. The development of the theory and method for planning optimal ALT for location-scale distribution, which is the most applied and mature theory of designing the optimal ALT plan, are described in detail. Taking this as the center of radiation, some problems that ALT now faces, such as the verification of the statistical model, limitation of sample size, solutions of resource limits, optimization of the test arrangement, and management of product complexity, are discussed, and the general ideas and methods of solving these problems are analyzed. Suggestions for selecting appropriate ALT plan design theories are proposed, and the urgent solved theory problems and opinions of their solutions are proposed. Based on the principle of convenience for engineers to select appropriate methods according to the problems found in practice, this paper reviews the development of optimal ALT plan design theory by taking the engineering problems arising from the ALT implementation as the main thread, provides guidelines on selecting appropriate theories for engineers, and proposes opinions about the urgent solved theory problems for researchers.

关键词： Accelerated life test Test plan Optimal design Reliability assessment

Fatal left atrial air embolism as a complication of percutaneous transthoracic lung biopsy:A case report

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World Journal of Clinical Cases 2022年第16期10卷 5456-5462页

作者： Yi-Wei Li Can Chen Ying Xu qian-ping Weng Shen-Xian qian Department of Critical Care Medicine Affiliated Hangzhou First People’s HospitalZhejiang University School of MedicineHangzhou 310006Zhejiang ProvinceChina Department of Hematology Affiliated Hangzhou First People’s HospitalZhejiang University School of MedicineHangzhou 310006Zhejiang ProvinceChina

BACKGROUND Computed tomography(CT)-guided percutaneous lung biopsy is a common protocol in the context of diagnostic thoracic oncology,but entails a risk of complications including systematic air embolism(SAE).While SAE is often well tolerated,it can be difficult to treat and may result in rapid mortality in some *** SUMMARY We report a rare case of left atrial SAE in a 71-year-old woman who underwent a CT-guided lung biopsy of a pulmonary nodule in the posterior basal segment of the right lower *** following needle extraction,she experienced a mild cough,hemoptysis,rapid-onset unconsciousness,and cardiopulmonary *** resuscitation was immediately performed,but the patient died 40 min after the procedure.A closer review of collected CT scans revealed the presence of a large volume of air within the left *** Although SAE is generally well tolerated and asymptomatic,interventional radiologists must be aware of the risk of fatal outcomes and establish appropriate emergency management *** this report,the characteristics,mechanisms,and treatment recommendations associated with SAE are discussed in an effort to improve the survival of affected patients.

关键词： Systematic air embolism Computed tomography-guided lung biopsy Bronchovenous fistula Risk-factors Emergency intervention Case report