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Acta Metallurgica Sinica(English Letters) 2021年第1期34卷 39-44页

作者： Lin-Yue Jia Wen-Bo Du Jin-Long Fu Zhao-Hui Wang Ke Liu Shu-Bo Li Xian Du College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

The Mg–12Gd–1Er–1Zn–0.9 Zr(wt%)alloy with ultra-high strength and ductility was developed via hot extrusion combined with pre-deformation and two-stage aging *** age-hardening behavior and microstructure evolution were ***-deformation introduced a large number of dislocations,resulting in strain hardening and higher precipitation strengthening in the subsequent two-stage *** a result,the alloy showed a superior strength–ductility balance with a yield strength of 506 MPa,an ultimate tensile strength of 549 MPa and an elongation of 8.2%at room *** finer and denserβ’precipitates significantly enhanced the strength,and the bimodal structure,smallβ-Mg5RE phase as well as denseγ’precipitates ensured the good ductility of the *** is suggested that the combination of pre-deformation and two-stage aging treatment is an eff ective method to further improve the mechanical properties of wrought Mg alloys.

关键词： Magnesium alloys Pre-deformation Two-stage aging Precipitation strengthening Mechanical properties

Smart materials for safe lithium-ion batteries against thermal runaway

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Journal of Energy Chemistry 2024年第7期94卷 360-392页

作者： Yu Ou Pan Zhou Wenhui Hou Xiao Ma Xuan Song Shuaishuai Yan Yang Lu Kai Liu Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

In recent years,the new energy storage system,such as lithium ion batteries(LIBs),has attracted much *** order to meet the demand of industrial progress for longer cycle life,higher energy density and cost efficiency,a quantity of research has been conducted on the commercial application of ***,it is difficult to achieve satisfying safety and cycling performance *** may be thermal runaway(TR),external impact,overcharge and overdischarge in the process of battery abuse,which makes the safety problem of LIBs more *** this review,we summarize recent progress in the smart safety materials design towards the goal of preventing TR of LIBs reversibly from different abuse *** from smart responsive materials and novel structural design,the safety of LIBs can be improved a *** expect to provide a comprehensive reference for the development of smart and safe lithium-based battery materials.

关键词： Lithium ion batteries(LIBs) Thermal runaway(TR) Smart materials Safe batteries Solid electrolyte interface(SEI)

Clustering in the Wireless Channel with a Power Weighted Statistical Mixture Model in Indoor Scenario

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China Communications 2019年第7期16卷 83-95页

作者： Yupeng Li Jianhua Zhang Pan Tang Lei Tian key Lab of Universal Wireless Communications Beijing University of Posts and Telecommunications Beijing 100876 China State key Lab of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

Cluster-based channel model is the main stream of fifth generation mobile communications, thus the accuracy of clustering algorithm is important. Traditional Gaussian mixture model (GMM) does not consider the power information which is important for the channel multipath clustering. In this paper, a normalized power weighted GMM (PGMM) is introduced to model the channel multipath components (MPCs). With MPC power as a weighted factor, the PGMM can fit the MPCs in accordance with the cluster-based channel models. Firstly, expectation maximization (EM) algorithm is employed to optimize the PGMM parameters. Then, to further increase the searching ability of EM and choose the optimal number of components without resort to cross-validation, the variational Bayesian (VB) inference is employed. Finally, 28 GHz indoor channel measurement data is used to demonstrate the effectiveness of the PGMM clustering algorithm.

关键词： channel multipath clustering mmWave Gaussian mixture model expectation maximization variational Bayesian inference

Inconsistent centralised versus noncentralised ischaemic stroke aetiology

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Stroke & Vascular Neurology 2020年第4期5卷 337-347页

作者： Yue Suo Jing Jing Xia Meng Zixiao Li Yuesong Pan Yong Jiang Xiaomeng Yang Huan Liu Hongyi Yan Liping Liu Xingquan Zhao Yilong Wang Hao Li Yongjun Wang Department of Neurology Beijing Tiantan HospitalBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina

Background and purpose The Trial of Org 10172 in Acute Stroke Treatment(TOAST)system is the most widely used aetiological categorisation system in clinical practice and *** studies have validated the accuracy of routine aetiological diagnosis of patients with ischaemic stroke according to the TOAST criteria when the reported subtype is assumed to be *** investigated the agreement between centralised and non-centralised(site-reported,at discharge)stroke subtypes in the Third China National Stroke Registry(CNSR-III),and analysed the influence of classification consistency on evaluation during hospitalisation and for secondary prevention *** All patients with ischaemic stroke from the CNSR-III study with complete diffusion-weighted imaging data were *** used multivariable Cox proportional-hazard regression models to evaluate the factors associated with consistency between centralised and non-centralised stroke *** analyses were conducted of the subgroup of patients with complete *** This study included 12180 patients(mean age,62.3 years;and women,31.4%).Agreement between centralised and non-centralised subtype was the highest for the large-artery atherosclerosis subtype stroke(77.4%of centralised patients),followed by the small-vessel occlusion subtype(40.6%of centralised patients).Agreements for cardioembolism and stroke of other determined aetiology subtypes were 38.7%and 12.2%,***-level and hospital-level factors were associated with the inconsistency between centralised/non-centralised aetiological *** inconsistency was related to differences in secondary prevention *** 15.3%of the newly diagnosed patients with cardioembolism underwent centralised subtyping with indications to receive oral anticoagulants at *** comparison,51.3%of the consistent cardioembolism group and 42.0%of the centrally reassigned cardioembolism group with anticoagulation i

关键词： prevention routine diagnosis

A new Upper Carboniferous stem-orthopteran （Insecta） from Ningxia （China）

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Insect Science 2012年第2期19卷 153-158页

作者： Olivier Béthoux Jun-Jie Gu Dong Ren College of Life Sciences Capital Normal UniversityBeijingChina 40 rue d'Aveillans 38770 La Motte d'AveillansFrance

During the Upper Carboniferous, orthopteran insects （grasshoppers, katydids, and crickets） were represented by numerous species distantly related to crown-orthopterans, such as lobeattid and cnemidolestodean insects. The panorthopterans, including total- orthopterans and their closest relatives, are represented by comparatively rarer species in localities of this period. Here we describe Heterologus duyiwuer sp. nov., an infrequent panorthopteran from the Late Carboniferous locality of Xiaheyan Village （Zhongwei City, Ningxia Hui Autonomous Region, China）. The only available specimen is composed of an isolated forewing exhibiting a combination of character states previously unknown, in particular the lack of posterior radius （RP） / anterior Media （MA） connection, late branchings of the media （M） and anterior cubitus （CuA）, and a branched posterior branch of the posterior cubitus （CuPb）. Based on its unusual branching pattern, the composite stem resulting from the fusion of CuA and CuPaa （second anterior branch of CuP） is assumed to be composed of a branched CuA and a simple CuPaa.

关键词： Archaeorthoptera homology Namurian stem-orthopterans Tupo Formation

Probing component contributions and internal polarization in silicon-graphite composite anode for lithium-ion batteries with an electrochemical-mechanical model

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Chinese Physics B 2022年第7期31卷 595-605页

作者： Yue Chen Fuliang Guo Lufeng Yang Jiaze Lu Danna Liu Huayu Wang Jieyun Zheng Xiqian Yu Hong Li beijing Advanced Innovation Center for Materials Genome Engineering Key Laboratory for Renewable EnergyBeijing Key Laboratory for New Energy Materials and DevicesInstitute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China beijing WeLion New Energy Technology Co. Ltd.Beijing 100176China Li Auto Inc. Beijing 101399China Tianmu Lake Institute of Advanced Energy Storage Technologies Liyang 213300China

Silicon–graphite(Si–Gr)composite anodes are attractive alternatives to replace Gr anodes for lithium-ion batteries(LIBs)owing to their relatively high capacity and mild volume ***,it is difficult to understand electrochemical interactions of Si and Gr in Si–Gr composite anodes and internal polarization of LIBs with regular experiment ***,we establish an electrochemical-mechanical coupled model to study the effect of rate and Si content on the electrochemical and stress behavior in a Si–Gr composite *** results show that the composites of Si and Gr not only improve the lithiation kinetics of Gr but also alleviate the voltage hysteresis of Si and decrease the risk of lithium plating in the negative ***'s more,the Si content is a tradeoff between electrode capacity and electrode volume ***,various internal polarization contributions of cells using Si–Gr composite anodes are quantified by the voltage decomposition *** results indicate that the electrochemical polarization of electrode materials and the electrolyte ohmic over-potential are dominant factors in the rate performance of cells,which provides theoretical guidance for improving the rate performance of LIBs using Si–Gr composite anodes.

关键词： Si–Gr electrochemical interactions polarization rate performance

The role of apparent diffusion coefficient values in characterization of solid focal liver lesions:a prospective and comparative clinical study

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Science China(Life Sciences) 2017年第1期60卷 16-22页

作者： Dawei Yang Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China National Clinical Research Center for Digestive Diseases Beijing 100050China

We evaluated and compared the diagnostic accuracy(DA) of apparent diffusion coefficient(ADC) values with that of lesion-to-liver ADC ratios in the characterization of solid focal liver lesions(FLLs).This prospective study was approved by the Institutional Human Ethics Board,after waiving written informed ***-weighted imaging and other routine magnetic resonance imaging were performed on 142 consecutive patients with suspected liver *** mean ADC values and lesion-to-liver ADC ratios were compared between benign and malignant solid *** operating characteristic analysis was *** study participants included 46 patients(28 men,18 women;mean age,52.5 years) with 57 solid FLLs(32 malignant and 25 benign FLLs).The mean ADC values and ADC ratios of benign solid FLLs were significantly higher than those of malignant lesions(P<0.01).The difference between the area under the receiver operating characteristic curve of the ADC values(0.699) and ADC ratios(0.752) was not *** study suggests that the DA of the ADC ratio is not significantly higher than that of ADC in characterizing solid FLLs.

关键词： magnetic resonance diffusion-weighted imaging lesion characterization liver sensitivity specificity

Prion Protein Expression is Correlated with Glioma Grades

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Virologica Sinica 2020年第4期35卷 490-493页

作者： Qiaoli Luo Yisong Wang Dongying Fan Shijie Wang Peigang Wang Jing An Department of Microbiology School of Basic Medical SciencesCapital Medical UniversityBeijing 100069China Center of Epilepsy Beijing Institute for Brain DisordersBeijing 100093China

Dear Editor,Glioma is the most common primary central nervous system(CNS)tumors in *** are classified into low-grade glioma(LGG,grades I–II)and high-grade glioma(HGG,grades III–IV)according to the World Health Organization classification guidelines(Louis et al.2007).Comparing to the LGG,the HGG becomes more aggressive and has a poorer median overall *** present,glioma is mainly treated by radiotherapy,chemotherapy and surgical resection,but the effect is not ideal,especially for the glioblastoma(GBM),which is the most malignant type of gliomas and is resistant to current therapy *** are several theories about the pathogenesis of glioma,such as radiation(Ohgaki and Kleihues 2005)。

关键词： glioma al. Glioma

Phase I study of chimeric anti-CD20 monoclonal antibody in Chinese patients with CD20-positive non-Hodgkin＇s lymphoma

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Chinese Journal of Cancer Research 2016年第2期28卷 197-208页

作者： Lin Gui Xiaohong Han Xiaohui He Yuanyuan Song Jiarui Yao Jianliang Yang Peng Liu Yan Qin Shuxiang Zhang Weijing Zhang Wenlin Gai Liangzhi Xie Yuankai Shi Department of Medical Oncology Beijing Key Laboratory of Clinical Study on Anticancer Molecular Targeted Drugs National Cancer Center/ Cancer Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100021 China Department of Lymphoma the 307th Hospital of Chinese People's Liberation Army & the Affiliated Hospital of Military Medical Sciences Beijing 100071 China Cell Culture Research and Development Center Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100176 China

Objective： This study was designed to determine the safety, pharmacokinetics and biologic effects of a humanmouse chimeric anti-CD20 monoclonal antibody （SCT400） in Chinese padents with CD20-positive B-cell non- Hodgkin＇s lymphoma （CD20 B-cell NHL）. SCT400 has an identical amino acid sequence as rituximab, with the exception of one amino acid in the CH1 domain of the heavy chain, which is common in Asians. Methods： Fifteen patients with CD20＋ B-cell NHL received dose-escalating SCT400 infusions （250 mg/m2： n=3; 375 mg/m2： n=9; 500 mg/m2： n=3） once weekly for 4 consecutive weeks with a 24-week follow-up period. The data of all patients were collected for pharmacoklnetics and pharmacodynamics analyses. Results： No dose-limiting toxicities were observed. Most drug-related adverse events were grade 1 or 2. Two patients had grade 3 or 4 ncutropenia. Under premedication, the drug-related infusion reaction was mild. A rapid, profound and durable depletion of circulating B cells was observed in all dose groups without significant effects on T cell count, natural killer （NK） cell count or immunoglobulin levels. No patient developed anti- SCT400 antibodies during the course of the study. SCT400 serum half-life （Tin）, maximum concentration （Cmax and area under the curve （AUC） generally increased between the first and fourth infusions （P〈0.05）. At the 375 mg/m2 dose, the T1/2 was 122.5±46.7 h vs. 197.0,75.0 11, respectively, and the Cmax was 200.6±20.2 pg/mL vs. 339.1±71.0 ng/mL, respectively. From 250 mg/m2 to 500 mg/m2, the Cmax and AUC increased significantly in a dose-dependent manner （P〈0.05）. Patients with a high tumor burden had markedly lower serum SCT400 concenmations compared with those without or with a low tumor burden. Of the 9 assessable patients, 1 achieved complete response and 2 achieved partial responses. Conclusions; SCT400 is well-tolerated and has encouraging preliminary efficacy in Chinese patients with CD20＋ B-cell NHL.

关键词： Chimeric anti-CD20 monodonal antibody non-Hodgldn's lymphoma phase I study

Molybdenum Concentration and the Risk of Spontaneous Preterm Birth: A Nested Case-Control Study — beijing municipality, China, 2018–2020

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China CDC weekly 2024年第13期6卷 261-266,I0005,I0006页

作者： Junhua Huang Wei Zheng Aili Wang Weiling Han Junxi Chen Hang An Lailai Yan Zhiwen Li Guanghui Li Division of Endocrinology and Metabolism Department of ObstetricsBeijing Obstetrics and Gynecology HospitalCapital Medical University.Beijing Maternal and Child Health Care HospitalBeijingChina Department of Obstetrics and Gynecology Beijing Luhe HospitalCapital Medical UniversityBeijingChina Institute of Reproductive and Child Health National Health Commission Key Laboratory of Reproductive HealthPeking UniversityBeijingChina Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijingChina Department of Laboratorial Science and Technology School of Public HealthPeking UniversityBeijingChina

What is already known about this topic?The level of molybdenum(Mo)in a mother’s urine has been linked to the growth rate of the fetus and the blood pressure levels in *** is added by this report?We evaluated the variations in maternal plasma Mo concentrations throughout pregnancy and their potential association with the risk of spontaneous preterm birth(SPB).What are the implications for public health practice?Future research must determine the Mo levels in pregnant women across various regions in ***,particular attention needs to be given to the potential increase in Mo concentration throughout pregnancy and its possible adverse impacts on the health of both the mother and the fetus.

关键词： mother urine pregnancy