期刊文献+
共找到16篇文章
< 1 >
每页显示 20 50 100
基于高管连锁网络的上市公司财务困境预测研究
1
作者 张晓晨 张晶 +1 位作者 方匡南 严晓东 《经济管理学刊》 2024年第1期181-198,共18页
上市公司财务困境的预测问题是金融学领域的热点研究问题之一,科学的财务困境预测有利于企业提高预警管理水平。高管连锁网络通过高管在多家公司兼任的方式在企业中形成网络,使企业之间的决策越来越紧密关联,对企业的行为和绩效产生影响... 上市公司财务困境的预测问题是金融学领域的热点研究问题之一,科学的财务困境预测有利于企业提高预警管理水平。高管连锁网络通过高管在多家公司兼任的方式在企业中形成网络,使企业之间的决策越来越紧密关联,对企业的行为和绩效产生影响,而现有的财务困境预测模型忽视了高管连锁网络的影响。针对具有网络结构的样本数据,本文提出了带样本网络结构的Logistic模型,根据系数是否受网络结构影响将变量分为网络结构变量和非网络结构变量,不同样本对应的网络结构变量系数是不同的,通过拉普拉斯(Laplacian)二次惩罚函数鼓励样本网络中有连接的样本对应的网络结构变量系数具有相似性。蒙特卡洛模拟表明该模型要优于其他方法。最后,本文应用所提方法基于高管连锁网络进行了财务困境预测研究。结果表明,将高管连锁网络信息纳入财务困境预测模型,可以提高模型预测的准确率。 展开更多
关键词 上市公司 财务困境预测 LOGISTIC模型 高管连锁网络
下载PDF
第一代酪氨酸激酶抑制剂治疗中发生进展的非小细胞肺癌血浆表皮生长因子受体(EGFR)T790M突变提示了失败部位并预测了临床预后:一项前瞻性观察研究 被引量:5
2
作者 Shirong zhang Lucheng Zhu +6 位作者 Bing Xia Enguo Chen Qiong Zhao xiaochen zhang Xueqin Chen Xufeng Chen Shenglin Ma 《癌症》 SCIE CAS CSCD 2018年第9期377-391,共15页
背景与目的血浆循环肿瘤DNA(circulating tumor DNA,ctDNA)是检测表皮生长因子受体(epidermal growth factor receptor,EGFR)T790M突变的理想方法。T790M突变是第一代EGFR酪氨酸激酶抑制剂(tyrosine kinase inhibitor,TKI)耐药的主要机... 背景与目的血浆循环肿瘤DNA(circulating tumor DNA,ctDNA)是检测表皮生长因子受体(epidermal growth factor receptor,EGFR)T790M突变的理想方法。T790M突变是第一代EGFR酪氨酸激酶抑制剂(tyrosine kinase inhibitor,TKI)耐药的主要机制。本研究旨在探讨ctDNA来源的T790M突变与非小细胞肺癌(non-small cell lung cancer,NSCLC)患者疾病失败部位及临床预后的关系。方法第一代TKI治疗发生进展的患者被分为局限胸内进展(chest limited,CF)、局限颅内进展(brain limited,BF)和其他部位进展(other,OF)组。采用扩增阻滞突变系统(amplification refractory mutation system,ARMS)和微滴式数字PCR(droplet digital PCR,ddPCR)对ctDNA中T790M突变进行了检测。采用Kaplan-Meier法分析了预后。结果 2种方法的总体一致性为78.3%。根据ARMS和ddPCR,OF组患者的T790M突变率明显高于BF组和CF组(P <0.001),OF组的T790M突变丰度也明显高于CF组和BF组(P <0.001)。AZD9291是T790M+患者最佳治疗选择,为EGFR-TKI治疗后进展的所有组中T790M+患者提供了最长的生存期;接受其他治疗的T790M-患者亚组的预后各不相同。结论本研究表明ctDNA中T790M突变与NSCLC患者EGFR-TKI治疗失败部位相关,失败部位和T790M突变状态对治疗选择和预后都有很大影响。 展开更多
关键词 非小细胞肺癌 表皮生长因子受体 T790M CTDNA 失败部位
下载PDF
Photocatalyst with Chloroplast-like Structure for Enhancing Hydrogen Evolution Reaction 被引量:2
3
作者 Fei Zhao Nan zhang +3 位作者 Hao Li xiaochen zhang Zhengtang Luo Yuhua Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2022年第4期1229-1237,共9页
Photosynthesis with the chloroplast works efficiently because of the envelope structure that serves to carry enzymes and to simultaneously maintain the spatial separation of photosynthesis and cellular respiration.Ins... Photosynthesis with the chloroplast works efficiently because of the envelope structure that serves to carry enzymes and to simultaneously maintain the spatial separation of photosynthesis and cellular respiration.Inspired by the spatially separated architecture,a chloroplast-like structured photocatalyst(PdS@CdS@MoS_(2)),in which the PdS and MoS_(2) function as enzymes in the chloroplast and CdS shell functions as the chloroplast envelope,was developed to improve the photocatalytic H_(2) evolution.In this unique nanoscale bionic structure,the poriferous CdS shell enhances light absorption,generates photoinduced carriers,and separates oxidation and reduction reactions.Meanwhile,PdS and MoS_(2) dual cocatalysts enhance the charge separation efficiency through forming a built-in electric field with CdS.We demonstrate that the separation efficiency of carriers,carrier lifetime,and the yield of H_(2) are both higher than that of CdS nanoparticles,evidencing the feasibility of the chloroplast-like structure in enhancing the photocatalyst activity.This work emphasizes the synergism of the three key processes of the photocatalytic reaction by simulating the chloroplast structure and provides a general synthesis strategy,the synthesis of novel structured for photocatalysts for diverse applications in the energy field. 展开更多
关键词 chloroplast-like structure co-catalysts DFT calculations photocatalytic H_(2)evolution spatial separation of carriers
下载PDF
Adolescent anxiety disorders and the developing brain: comparing neuroimaging findings in adolescents and adults 被引量:2
4
作者 Shuqi Xie xiaochen zhang +1 位作者 Wenhong Cheng Zhi Yang 《General Psychiatry》 CSCD 2021年第4期23-31,共9页
Adolescence is the peak period for the incidence of anxiety disorders.Recent findings have revealed the immaturity of neural networks underlying emotional regulation in this population.Brain vulnerability to anxiety i... Adolescence is the peak period for the incidence of anxiety disorders.Recent findings have revealed the immaturity of neural networks underlying emotional regulation in this population.Brain vulnerability to anxiety in adolescence is related to the unsynchronised development of anxiety-relevant brain functional systems.However,our current knowledge on brain deficits in adolescent anxiety is mainly borrowed from studies on adults.Understanding adolescent-specific brain deficits is essential for developing biomarkers and brain-based therapies targeting adolescent anxiety.This article reviews and compares recent neuroimaging literature on anxiety-related brain structural and functional deficits between adolescent and adult populations,and proposes a model highlighting the differences between adolescence and adulthood in anxiety-related brain networks.This model emphasises that in adolescence the emotional control system tends to be hypoactivated,the fear conditioning system is immature,and the reward and stress response systems are hypersensitive.Furthermore,the striatum’s functional links to the amygdala and the prefrontal cortex are strengthened,while the link between the prefrontal cortex and the amygdala is weakened in adolescence.This model helps to explain why adolescents are vulnerable to anxiety disorders and provides insights into potential brain-based approaches to intervene in adolescent anxiety disorders. 展开更多
关键词 ADOLESCENT DISORDERS CORTEX
下载PDF
INCloud:integrated neuroimaging cloud for data collection,management,analysis and clinical translations
5
作者 Qingfeng Li Lijuan Jiang +6 位作者 Kaini Qiao Yang Hu Bing Chen xiaochen zhang Yue Ding Zhi Yang Chunbo Li 《General Psychiatry》 CSCD 2021年第6期58-65,共8页
Background Neuroimaging techniques provide rich and accurate measures of brain structure and function,and have become one of the most popular methods in mental health and neuroscience research.Rapidly growing neuroima... Background Neuroimaging techniques provide rich and accurate measures of brain structure and function,and have become one of the most popular methods in mental health and neuroscience research.Rapidly growing neuroimaging research generates massive amounts of data,bringing new challenges in data collection,large-scale data management,efficient computing requirements and data mining and analyses.Aims To tackle the challenges and promote the application of neuroimaging technology in clinical practice,we developed an integrated neuroimaging cloud(INCloud).INCloud provides a full-stack solution for the entire process of large-scale neuroimaging data collection,management,analysis and clinical applications.Methods INCloud consists of data acquisition systems,a data warehouse,automatic multimodal image quality check and processing systems,a brain feature library,a high-performance computing cluster and computer-aided diagnosis systems(CADS)for mental disorders.A unique design of INCloud is the brain feature library that converts the unit of data management from image to image features such as hippocampal volume.Connecting the CADS to the scientific database,INCloud allows the accumulation of scientific data to continuously improve the accuracy of objective diagnosis of mental disorders.Results Users can manage and analyze neuroimaging data on INCloud,without the need to download them to the local device.INCloud users can query,manage,analyze and share image features based on customized criteria.Several examples of'mega-analyses'based on the brain feature library are shown.Conclusions Compared with traditional neuroimaging acquisition and analysis workflow,INCloud features safe and convenient data management and sharing,reduced technical requirements for researchers,high-efficiency computing and data mining,and straightforward translations to clinical service.The design and implementation of the system are also applicable to imaging research platforms in other fields. 展开更多
关键词 IMAGE DIAGNOSIS TRANSLATION
下载PDF
Synergy of phosphorus vacancies and build-in electric field into NiCo/NiCoP Mott-Schottky integrated electrode for enhanced water splitting performance
6
作者 xiaochen zhang Hui Xue +5 位作者 Jing Sun Niankun Guo Tianshan Song Jiawen Sun Yi-Ru Hao Qin Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第2期604-610,共7页
Vacancy engineering and Mott-Schottky heterostructure can accelerate charge transfer,regulate adsorption energy of reaction intermediates,and provide additional active sites,which are regarded as valid means for impro... Vacancy engineering and Mott-Schottky heterostructure can accelerate charge transfer,regulate adsorption energy of reaction intermediates,and provide additional active sites,which are regarded as valid means for improving catalytic activity.However,the underlying mechanism of synergistic regulation of interfacial charge transfer and optimization of electrocatalytic activity by combining vacancy and Mott-Schottky junction remains unclear.Herein,the growth of a bifunctional NiCo/NiCoP Mott-Schottky electrode with abundant phosphorus vacancies on foam nickel(NF)has been synthesized through continuous phosphating and reduction processes.The obtained NiCo/NiCoP heterojunctions show remarkable OER and HER activities,and the overpotentials for OER and HER are as low as 117 and 60 mV at 10 mA/cm^(2) in 1 mol/L KOH,respectively.Moreover,as both the cathode and anode of overall water splitting,the voltage of the bifunctional NiCo/NiCoP electrocatalyst is 1.44 V at 10 mA/cm^(2),which are far exceeding the benchmark commercial electrodes.DFT theoretical calculation results confirm that the phosphorus vacancies and build-in electric field can effectively accelerate ion and electron transfer between NiCo alloy and NiCoP semiconductor,tailor the electronic structure of the metal centers and lower the Gibbs free energy of the intermediates.Furthermore,the unique self-supported integrated structure is beneficial to facilitate the exposure of the active site,avoid catalyst shedding,thus improving the activity and structural stability of NiCo/NiCoP.This study provides an avenue for the controllable synthesis and performance optimization of Mott-Schottky electrocatalysts. 展开更多
关键词 Mott-Schottky Build-in electric field Phosphorus vacancies PHOSPHIDES Overall water splitting
原文传递
An Integrated Carbon Dioxide Capture and Methanation Process
7
作者 xiaochen zhang Mengzhu Li +21 位作者 Xingwu Liu Ang Li Yuchen Deng Mi Peng Yu zhang Charlotte Vogt Matteo Monai Junxian Gao Xuetao Qin Yao Xu Qiaolin Yu Meng Wang Guofu Wang Zheng Jiang Xiaodong Han Casper Brady Wei-Xue Li Wu Zhou Jin-Xun Liu Bingjun Xu Bert M.Weckhuysen Ding Ma 《CCS Chemistry》 CSCD 2024年第5期1174-1183,共10页
Reducing the ever-growing level of CO_(2)in the atmosphere is critical for the sustainable development of human society in the context of global warming.Integration of the capture and upgrading of CO_(2)is,therefore,h... Reducing the ever-growing level of CO_(2)in the atmosphere is critical for the sustainable development of human society in the context of global warming.Integration of the capture and upgrading of CO_(2)is,therefore,highly desirable since each process step is costly,both energetically and economically.Here,we report a CO_(2)direct air capture(DAC)and fixation process that produces methane.Low concentrations of CO_(2)(∼400 ppm)in the air are captured by an aqueous solution of sodium hydroxide to form carbonate.The carbonate is subsequently hydrogenated to methane,which is easily separated from the reaction system,catalyzed by TiO2-supported Ru in the aqueous phase with a selectivity of 99.9%among gas-phase products.The concurrent regenerated hydroxide,in turn,increases the alkalinity of the aqueous solution for further CO_(2)capture,thereby enabling this one-ofits-kind continuous CO_(2)capture and methanation process.Engineering simulations demonstrate the energy feasibility of this CO_(2)DAC and methanation process,highlighting its promise for potential largescale applications. 展开更多
关键词 CO_(2)capture and methanation process sodium hydroxide CARBONATE Ru/TiO_(2) catalytic mechanism CO_(2)activation and hydrogenation
原文传递
Refractive index sensing based on a twisted nano-kirigami metasurface
8
作者 SHUQI QIAO xiaochen zhang +7 位作者 QINGHUA LIANG YANG WANG CHANG-YIN JI XIAOWEI LI LAN JIANG SHUAI FENG HONGLIAN GUO JIAFANG LI 《Photonics Research》 SCIE EI CAS CSCD 2024年第2期218-225,共8页
Plasmonic sensing technology has attracted considerable attention for high sensitivity due to the ability to effectively localize and manipulate light.In this study,we demonstrate a refractive index(RI)sensing scheme ... Plasmonic sensing technology has attracted considerable attention for high sensitivity due to the ability to effectively localize and manipulate light.In this study,we demonstrate a refractive index(RI)sensing scheme based on open-loop twisted meta-molecule arrays using the versatile nano-kirigami principle.RI sensing has the features of a small footprint,flexible control,and simple preparation.By engineering the morphology of meta-molecules or the RI of the ambient medium,the chiral surface lattice resonances can be significantly enhanced,and the wavelength,intensity,and sign of circular dichroism(CD)can be flexibly tailored.Utilizing the relation between the wavelength of the CD peak and the RI of the superstrate,the RI sensor achieves a sensitivity of 1133 nm/RIU.Additionally,we analyze these chiroptical responses by performing electromagnetic multipolar decomposition and electric field distributions.Our study may serve as an ideal platform for applications of RI measurement and provide new insights into the manipulation of chiral light–matter interactions. 展开更多
关键词 TWISTED CHIRAL INDEX
原文传递
Cu@Cu_(2)O/carbon for efficient desalination in capacitive deionization 被引量:1
9
作者 Fei Yu Haoyuan Yin +3 位作者 Xueting Bai Junyao Pan xiaochen zhang Jie Ma 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第12期318-322,共5页
Electrode materials with strong desalting ability is an important research direction of capacitive deionization.In this study,HKUST-1 was successfully synthesized by the solvothermal method,and MOFsderived porous carb... Electrode materials with strong desalting ability is an important research direction of capacitive deionization.In this study,HKUST-1 was successfully synthesized by the solvothermal method,and MOFsderived porous carbon/Cu@Cu_(2)O composites were prepared by simple pyrolysis as cathode materials for CDI.After high-temperature pyrolysis,the Cu^(+) site with unsaturated coordination is generated,and the structure changes from micropores to the coexistence of mesoporous and micropores.The complex pore structure is conducive to strengthening ion migration and diffusion.The results show that the porous carbon/Cu@Cu_(2)O materials derived from MOFs depend on the pseudocapacitance behavior for capacitive deionization and desalination.At a voltage window of-1.2V~1.2V,a current density of 40mA/g.and 5 mmol/L NaCl,the HDC-1100 exhibited the best desalting capacity of 30.9 mg/g.HDC-1100 also has good cycle stability.After 20 cycles of adsorption and desorption,the desalting capacity almost does not decrease.Therefore,MOFs derived porous carbon/Cu@Cu_(2)O composites are expected to be an excellent choice for CDI cathode materials. 展开更多
关键词 Metal-organic framework Derived carbon Capacitive deionization HKUST-1
原文传递
Effect of Silicon and Aluminum Addition on Corrosion Behavior of ODS Iron-Based Alloys in Liquid Lead–Bismuth Eutectic
10
作者 Jing Li xiaochen zhang +4 位作者 Haibin Ma Liangyin Xiong Shi Liu Qisen Ren Zhengzheng Pang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2023年第5期732-744,共13页
The long-term corrosion behaviors of four variants of oxide dispersion strengthened(ODS)iron-based alloys in the stagnant oxygen-saturated lead–bismuth eutectic(LBE)at 550℃ were studied herein.The effects of silicon... The long-term corrosion behaviors of four variants of oxide dispersion strengthened(ODS)iron-based alloys in the stagnant oxygen-saturated lead–bismuth eutectic(LBE)at 550℃ were studied herein.The effects of silicon and aluminum content on the thickness,morphology and composition of the oxide scale were explored with the aid of X-ray diffraction(XRD),scanning electron microscopy(SEM),electron probe micro-analyzer(EPMA)and X-ray photoelectron spectroscopy(XPS).The addition of 1.5 wt%silicon is not able to contribute to forming a protective external silicon oxide film on the surface of aluminum-free ODS iron-based alloy,while the addition of aluminum promotes the formation of a thin and continuous alumina oxide scale.In the meantime,an appropriate amount of silicon becomes the heterogeneous nucleation site for alumina during the initial stage of oxidation,giving rise to the rapid formation of a protective alumina scale.However,excessive silicon has a negative impact on the formation of continuous alumina scale,because it may compete with aluminum to absorb more oxygen.The result of oxidation kinetics in ODS iron-based alloy shows that the parabolic rate constant of the alumina oxide scale is 3–4 orders of magnitude lower than that of the scale mainly composed of iron and chromium oxide. 展开更多
关键词 Pb-Bi corrosion Oxide dispersion strengthened(ODS)ferritic alloy Silicon and aluminum addition Oxide scale
原文传递
过表达甲基转移酶样3修复炎症来源牙周膜干细胞的成骨能力
11
作者 陈欣 张校晨 +1 位作者 秦文 金作林 《中华口腔医学研究杂志(电子版)》 CAS 2023年第1期15-25,共11页
目的探讨N^(6)-甲基腺嘌呤(m6A)修饰与甲基转移酶样3(METTL3)在牙周膜干细胞(PDLSC)成骨分化和成脂分化中的作用。方法使用流式细胞术、细胞集落形成实验分别鉴定PDLSC的表面标志物和增殖能力。通过茜素红染色和油红O染色分别检测PDLSC... 目的探讨N^(6)-甲基腺嘌呤(m6A)修饰与甲基转移酶样3(METTL3)在牙周膜干细胞(PDLSC)成骨分化和成脂分化中的作用。方法使用流式细胞术、细胞集落形成实验分别鉴定PDLSC的表面标志物和增殖能力。通过茜素红染色和油红O染色分别检测PDLSC的成骨和成脂分化潜能。在人牙周膜干细胞(hPDLSC)和炎症来源牙周膜干细胞(pPDLSC)中分别构建METTL3过表达和敲低模型,成骨诱导一定时间,通过实时定量反转录聚合酶链反应(RT-PCR)、蛋白免疫印迹(Western blot)、茜素红染色和油红O染色分别在mRNA水平、蛋白水平和宏观水平检测成骨和成脂的变化。两样本比较使用独立样本t检验,多组样本比较使用单因素方差分析。结果(1)流式细胞术结果显示,hPDLSC和pPDLSC均阳性表达CD29(100.0%,98.0%)、CD105(100.0%,99.5%)和CD146(31.5%,17.8%),阴性表达CD34(1.3%,0.4%)和CD45(1.4%,0.4%)。(2)细胞集落形成实验结果显示,hPDLSC和pPDLSC的集落形成数量分别为55±5和72±8,hPDLSC的细胞增殖能力较pPDLSC低(t=3.16,P=0.034)。(3)茜素红染色和油红O染色说明,两种细胞均具有成骨和成脂分化能力,hPDLSC具有更强的成骨分化能力(t=27.77,P<0.001),而pPDLSC具有更强的成脂分化能力(t=5.02,P=0.007)。(4)成骨诱导培养7 d后的慢病毒转染模型中,METTL3过表达组比过表达对照组的成骨关键基因Runx2的mRNA表达水平高,在hPDLSC和pPDLSC中的METTL3过表达组的表达量是3.63±1.15和1.61±0.38,分别是其过表达对照组的3.39倍(t=3.777,P=0.020)和1.71倍(t=2.948,P=0.042);而在METTL3敲低组较敲低对照组低,在hPDLSC和pPDLSC中的METTL3敲低组的表达量是0.16±0.03和0.26±0.07,分别是其敲低对照组的0.15倍(t=9.669,P<0.001)和0.26倍(t=8.767,P<0.001)。同样地,Runx2的蛋白表达水平也发生相同改变。将转染后的细胞进行21 d的成骨诱导培养后进行茜素红染色,结果显示METTL3过表达组较过表达对照组染色深且钙化结节较大,定量分析结果显示在hPDLSC和pPDLSC中的METTL3过表达组是28.47%±3.82%和8.55%±0.43%,分别是其过表达对照组的1.78倍(t=5.012,P=0.007)和1.76倍(t=7.293,P=0.002),而在METTL3敲低组较敲低对照组染色浅且钙化结节较小,定量分析结果显示在hPDLSC和pPDLSC中的METTL3敲低组是6.36%±2.00%和3.78%±0.56%,分别是其敲低对照组的0.35倍(t=4.444,P=0.011)和0.43倍(t=5.337,P=0.006);将转染后的细胞进行21 d的成脂诱导培养,再进行油红O染色,结果显示脂滴的大小及数量在METTL3过表达组较过表达对照组少,定量分析结果显示在hPDLSC和pPDLSC中的METTL3过表达组是0.89%±0.11%和1.10%±1.15%,分别是其过表达对照组的0.24倍(t=5.454,P=0.006)和0.49倍(t=2.935,P=0.043),而在METTL3敲低组则比敲低对照组的脂滴更大且多,定量分析结果显示在hPDLSC和pPDLSC中的METTL3敲低组是3.60%±1.08%和5.34%±1.31%,分别是其敲低对照组的1.94倍(t=2.794,P=0.049)和2.93倍(t=4.131,P=0.015)。结论pPDLSC的METTL3表达水平低于hPDLSC;METTL3的过表达可促进hPDLSC和pPDLSC的成骨分化,并抑制两者的成脂分化。 展开更多
关键词 甲基转移酶样3 N^(6)-甲基腺嘌呤修饰 牙周膜干细胞 成骨分化
原文传递
Evaluation of airborne transmission risk in university towns based on IEQ surveys
12
作者 Yufan Chang xiaochen zhang +6 位作者 Ge Song Jing Liu Chen Lin Jinjun Ye Jie Hu Lei Tang Zhengtao Ai 《Energy and Built Environment》 2023年第5期493-505,共13页
This study aims to evaluate airborne transmission risk in university towns during the COVID-19 pandemic based on surveys of indoor environmental quality(IEQ).Both on-site measurements and questionnaire surveys were ca... This study aims to evaluate airborne transmission risk in university towns during the COVID-19 pandemic based on surveys of indoor environmental quality(IEQ).Both on-site measurements and questionnaire surveys were carried out in public buildings in university towns in Changsha,China.Air temperature,relative humidity,and CO 2 concentration in one library,ten classrooms,eight canteens,seven restaurants,and sixteen malls were mea-sured.2220 valid questionnaires concerning occupants’sensation on thermal environment,air movement,and indoor air quality were collected.A 3-level evaluation method of airborne transmission risk that is dependent on building type and indoor CO 2 concentration was developed.Excessive CO 2 concentration is found in library(1045 ppm),classrooms(1151 ppm),restaurants(1242 ppm),and malls(1057 ppm).The percentage time of“high risk”accounts for 18-100%in these buildings.The results reveal a serious problem:numerous public buildings in China and probably other resource limited countries are not basically prepared and equipped to cope with airborne transmission.This fact should be taken into account when developing guidelines and formu-lating mitigation measures.Real-time monitoring and displaying IEQ and thus the transmission risk level should be an important way to be widely implemented in public buildings. 展开更多
关键词 University town On-site measurement Questionnaire survey Indoor environmental quality COVID-19
原文传递
预循环应力对高速列车关键结构用铝合金材料疲劳裂纹扩展行为的影响 被引量:1
13
作者 张啸尘 孟维迎 +2 位作者 邹德芳 周鹏 石怀涛 《金属学报》 SCIE EI CAS CSCD 北大核心 2019年第10期1243-1250,共8页
对服役多年的高速列车关键结构用铝合金材料进行断裂力学性能测试,探究其稳态扩展区域和近门槛值区域的疲劳裂纹扩展行为,阐释服役材料力学行为的变化规律。鉴于服役材料疲劳裂纹扩展行为的折线特征,开展不同水平预循环应力作用下的断... 对服役多年的高速列车关键结构用铝合金材料进行断裂力学性能测试,探究其稳态扩展区域和近门槛值区域的疲劳裂纹扩展行为,阐释服役材料力学行为的变化规律。鉴于服役材料疲劳裂纹扩展行为的折线特征,开展不同水平预循环应力作用下的断裂力学实验研究,剖析预循环应力对材料断裂力学性能"锻炼"效应的影响,建立合理的寿命预测模型,并与实测数据进行对比。研究表明:服役材料在稳态裂纹扩展阶段的疲劳裂纹扩展行为呈折线特征,近门槛值区域的延迟扩展行为是促使折线现象产生的原因;经历预循环应力作用后,材料疲劳裂纹扩展速率与应力强度因子范围(da/d N-ΔK)的关系曲线在稳态裂纹扩展的初期阶段呈现类似服役材料的折转行为;不同水平的预循环应力对材料断裂力学性能的"锻炼"效果不同,存在能够使材料达到最佳"锻炼"效果的预循环应力水平;对于折转型da/d N-ΔK关系曲线,本工作所建立的计算模型能够更加准确地预测材料的疲劳裂纹扩展寿命。 展开更多
关键词 高速列车 疲劳裂纹扩展行为 预循环应力 “锻炼”效应 疲劳寿命预测
原文传递
Epidermal growth factor receptor (EGFR) T790M mutation identified in plasma indicates failure sites and predicts clinical prognosis in non-small cell lung cancer progression during first-generation tyrosine kinase inhibitor therapy: a prospective observational study 被引量:13
14
作者 Shirong zhang Lucheng Zhu +6 位作者 Bing Xia Enguo Chen Qiong Zhao xiaochen zhang Xueqin Chen Xufeng Chen Shenglin Ma 《Cancer Communications》 SCIE 2018年第1期305-318,共14页
Introduction:Plasma circulating tumor DNA(ctDNA)is an ideal approach to detecting the epidermal growth factor receptor(EGFR)T790M mutation,which is a major mechanism of resistance to first-generation EGFR-tyrosine kin... Introduction:Plasma circulating tumor DNA(ctDNA)is an ideal approach to detecting the epidermal growth factor receptor(EGFR)T790M mutation,which is a major mechanism of resistance to first-generation EGFR-tyrosine kinase inhibitor(TKI)therapy.The present study aimed to explore the association of ctDNA-identified T790M mutation with disease failure sites and clinical prognosis in non-small cell lung cancer(NSCLC)patients.Methods:Patients who progressed on first-generation TKIs were categorized into failure site groups of chest limited(CF),brain limited(BF)and other(OF).Amplification refractory mutation system(ARMS)and droplet digital PCR(ddPCR)were used to identify the T790M mutation in ctDNA.Prognosis was analyzed with Kaplan-Meier methods.Results:Overall concordance between the two methods was 78.3%.According to both ARMS and ddPCR,patients in the OF group had a significantly higher rate of T790M mutation than did patients in the BF and CF groups(P<0.001),and a significantly higher T790M mutation rate was also observed in OF-group patients than in those in the CF and BF groups(P<0.001).AZD9291 was found to be an excellent treatment option and yielded the longest survival for T790M+patients in all groups who had progressed on EGFR-TKIs;for other treatments,the prognosis of T790M−patient subgroups varied.Conclusions:The present study demonstrates that T790M mutation in ctDNA is associated with failure sites for NSCLC patients after EGFR-TKI therapy and indicates that both failure site and T790M mutational status greatly influ-ence treatment selection and prognosis. 展开更多
关键词 Non-small cell lung cancer Epidermal growth factor receptor T790M CTDNA Failure sites
原文传递
Deep transfer network of heterogeneous domain feature in machine translation
15
作者 Yupeng Liu Yanan zhang xiaochen zhang 《High-Confidence Computing》 2022年第4期8-13,共6页
In order to address the shortcoming of feature representation limitation in machine translation(MT)system,this paper presents a feature transfer method in MT.Meta feature transfer of the decoding process considered no... In order to address the shortcoming of feature representation limitation in machine translation(MT)system,this paper presents a feature transfer method in MT.Meta feature transfer of the decoding process considered not only their own translation system,but also transferred knowledge of another translation system.The domain meta feature and the objective function of domain adaptation are used to better model the domain transfer task.In this paper,extensive experiments and comparisons are made.The experiment results show that the proposed model has a significant improvement in domain transfer task.The first model has better performance than baseline system,which improves 3.06 BLEU score on the news test set,improves 3.27 BLEU score on the education test set,and improves 3.93 BLEU score on the law test set;The second model improves 3.16 BLEU score on the news test set,improves 3.54 BLEU score on the education test set,and improves 4.2 BLEU score on the law test set. 展开更多
关键词 Neural translation model Deep transfer network Heterogeneous domain Meta feature
原文传递
Application of metal-organic frameworks to the anode interface in metal batteries
16
作者 Ze Liu xiaochen zhang +1 位作者 Jinlong Luo Yingjian Yu 《Chinese Chemical Letters》 SCIE CAS 2024年第11期182-202,共21页
Metal batteries have attracted considerable attention from researchers because of their low reduction voltage and high specific capacity.However,the reduction in the capacity and lifespan of batteries caused by the de... Metal batteries have attracted considerable attention from researchers because of their low reduction voltage and high specific capacity.However,the reduction in the capacity and lifespan of batteries caused by the dendrite growth of metal anode limits the development of metal batteries.Metal-organic frameworks (MOFs) can be used to protect metal anodes owing to their advantages of ideal specific surface area,tunable porosity,and physiochemical stability in electrolytes.Therefore,MOFs have been extensively investigated in metal batteries.The introduction of MOFs to the metal anode interface can greatly improve the performance of batteries.In this review,the synthesis methods of typical MOFs and their derivatives,their protective mechanism on the metal anode,including Li,Na,K,Zn,and Mg,and their effects on the performance of metal batteries were elucidated.This review would help to design and apply MOFs to the anode interface in metal batteries. 展开更多
关键词 Metal-organic frameworks Metal batteries Anode interface Dendrite growth Synthesis methods
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部