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循环加卸载下不同冲击损伤砂岩的力学特性研究

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黑龙江工业学院学报（综合版） 2024年第6期24卷 101-106页

作者：杨莉董春亮郝建平张博文安徽理工大学土木建筑学院安徽淮南232001

针对地下岩体工程在开挖掘进后因循环扰动导致围岩劣化和失稳问题,以冲击损伤砂岩为研究对象,开展三轴循环加卸载试验,研究循环加卸载条件下冲击损伤岩石的性能劣化和破坏规律。研究结果表明,冲击损伤越大的砂岩试样,在临近峰值强度时,... 详细信息

针对地下岩体工程在开挖掘进后因循环扰动导致围岩劣化和失稳问题,以冲击损伤砂岩为研究对象,开展三轴循环加卸载试验,研究循环加卸载条件下冲击损伤岩石的性能劣化和破坏规律。研究结果表明,冲击损伤越大的砂岩试样,在临近峰值强度时,其轴向应变会出现急速增长的现象;砂岩的塑性应变随循环次数的增加不断累积,在裂纹不稳定发展阶段,塑性应变大幅度增长;在弹性模量方面,研究发现同一循环等级下,砂岩试样的冲击损伤越大,其对应的割线弹性模量越小,抵抗变形的能力越弱;关于泊松比的研究发现,三种不同冲击损伤砂岩试样在试验过程中都表现出相似的变化趋势,先加速上升,然后缓慢增加,最后急剧增长。但损伤度越大的砂岩试样在试验后期表现出更明显的扩容现象,泊松比增加也更为显著。

关键词：不同冲击损伤循环加卸载力学特性割线弹性模量泊松比

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1990-2019年中国白血病发病率与死亡率年龄-时期-队列分析

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现代肿瘤医学 2024年第7期32卷 1334-1340页

作者：王兰兰刘广超李小凡郝建萍新疆医科大学第一附属医院血液中心新疆乌鲁木齐830054 新疆医科大学公共卫生学院新疆乌鲁木齐830011

目的:分析1990-2019年中国居民白血病发病及死亡随年龄、时期及队列的变化趋势,为白血病研究提供参考依据。方法:基于1990-2019年中国居民白血病发病率及死亡率数据,利用Joinpoint回归模型分析白血病发病率及死亡率的变化趋势。运用年龄... 详细信息

目的:分析1990-2019年中国居民白血病发病及死亡随年龄、时期及队列的变化趋势,为白血病研究提供参考依据。方法:基于1990-2019年中国居民白血病发病率及死亡率数据,利用Joinpoint回归模型分析白血病发病率及死亡率的变化趋势。运用年龄-时期-队列(age-period-cohort,APC)模型分析年龄、时期、队列对发病率及死亡率变化的影响。结果:1990-2019年中国居民男性及女性发病率的年平均变化百分率(average annual percentage change,AAPC)分别为-0.35(P<0.01)和-0.98(P<0.01),男性及女性死亡率的AAPC分别为-1.53(P<0.01)和-2.28(P<0.01)。APC模型结果显示:年龄发病及死亡风险随着年龄的增加,均先降低后升高,呈U型分布;时期发病风险随着时期的增加而上升,时期死亡风险则呈下降趋势;队列发病及死亡风险随着出生队列的推移均呈先上升后下降的趋势。结论:1990-2019年全国白血病发病率及死亡率总体呈下降趋势,人群白血病发病风险和死亡风险受年龄、时期和出生队列影响较大,加强对高危人群的防治,有助于降低我国白血病疾病负担。

关键词：白血病 Joinpoint回归模型年龄-时期-队列模型

Parametric formation control of multiple nanosatellites for cooperative observation of China Space Station

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Astrodynamics 2024年第1期8卷 77-95页

作者： hao Zhou Bohan Jiao Zhaohui Dang jianping Yuan School of Astronautics Northwestern Polytechnical UniversityXi’an710072China National Key Laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi’an710072China

This study proposes a parametric formation control method for the cooperative observation of the China Space Station(CSS)using multiple ***,a simplified geometrical model of the CSS is constructed using fundamental solids,such as the capsule body and ***,the spacecraft formation configuration for the observation mission is characterized by a three-dimensional(3D)Lissajous curve using related design parameters under the full-coverage observation requirements of specific parts,such as the CSS connecting section and collision avoidance ***,a double-layer control law is designed for each nanosatellite,in which the upper layer is a distributed observer for recognizing the target formation configuration parameters,and the lower layer is a trajectory-tracking controller to make the nanosatellite converge to its temporary target position calculated from the upper layer’s *** closed-loop control stability is proven under the condition that the communication network topology of the nanosatellite cluster contains a directed spanning ***,the control method is verified by numerical simulation,where the CSS connecting section is selected as the observation target,and ten small nanosatellites are assumed to perform the cooperative observation *** simulation results demonstrate that the double-layer control law is robust to single-point communication failures and suitable for the accompanying missions of large space objects with multiple nanosatellites.

关键词： China Space Station(CSS) cooperative observation parametric formation 3D Lissajous curve double-layer system

PBL教学法在血液内科教学实践中的应用研究

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中国卫生产业 2024年第6期21卷 161-164页

作者：秦玉婷穆耶赛尔·玉苏普郝建萍新疆医科大学第一附属医院血液病中心血液二科新疆维吾尔自治区乌鲁木齐830000

目的分析问题为导向的教学法(Problem-based Learning,PBL)教学法在血液内科教学实践中的应用效果。方法选取2022年10月—2023年10月在新疆医科大学第一附属医院血液内科实习的80名实习生为研究对象,根据随机数字表法分为对照组与观察组... 详细信息

目的分析问题为导向的教学法(Problem-based Learning,PBL)教学法在血液内科教学实践中的应用效果。方法选取2022年10月—2023年10月在新疆医科大学第一附属医院血液内科实习的80名实习生为研究对象,根据随机数字表法分为对照组与观察组,各40名。对照组采取传统教学法,观察组采取PBL教学法,比较两组学生笔试成绩和满意度。结果观察组综合测评成绩(病例分析能力、临床能力、独立思考能力)以及面试成绩(实践能力、临床反应能力、思维能力)均高于对照组,差异有统计学意义(P均<0.05);观察组学生激发学习兴趣(90.00%)、提高自学能力(92.50%)、加深知识理解(92.50%)、提高临床技能(95.00%)、培养临床思维(95.00%)、增强语言表达(92.50%)的各项满意度均高于对照组,差异有统计学意义(P均<0.05)。结论在血液科临床实习过程中,PBL教学方法比传统的教学方法要有效,能明显地提高学生的总体成绩和满意度,值得借鉴。

关键词：以问题为基础的学习法教学血液内科临床实习

Clustering-based maintainability demonstration for complex systems with a mixed maintenance time distribution

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Journal of Systems Engineering and Electronics 2019年第6期30卷 1260-1271页

作者： WU Zhenya hao jianping Department of Equipment Command and Management Shijiazhuang Campus of Army Engineering University

During maintainability demonstration,the maintenance time for complex systems consisting of mixed technologies generally conforms to a mixture *** existing maintainability standards and guidance do not explain explicitly how to deal with this *** paper develops a comprehensive maintainability demonstration method for complex systems with a mixed maintenance time *** of all,a K-means algorithm and an expectation-maximization(EM)algorithm are used to partition the maintenance time data for all possible *** Bayesian information criterion(BIC)is then used to choose the optimal *** this,the clustering results for equipment are obtained according to their degree of *** degree of similarity for the maintainability of different kinds of equipment is then determined using the projection *** using a Bootstrap method,the prior distribution is obtained from the maintenance time data for the most similar ***,a test method based on Bayesian theory is outlined for the maintainability ***,the viability of the proposed approach is illustrated by means of an example.

关键词： complex system maintainability demonstration mix ture distribution model Bayesian test.

Enhancement of heavy metals desorption from the soil by eddy deep leaching in hydrocyclone

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Journal of Environmental Sciences 2024年第1期135卷 242-251页

作者： Ning Wang hao Lu Bo Liu Tai Xiong jianping Li Hualin Wang Qiang Yang School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China National Engineering Laboratory for High Concentration Refractory Organic Wastewater Treatment Technology East China University of Science and TechnologyShanghai 200237China

An eddy deep leaching technology was developed in this paper to address the challenge of treating heavy metal contaminants in industrial mining *** desorption effect of As,Cd,Sb and Pb was investigated utilizing chemical leaching and physical eddy *** was found that the heavy metals concentration increased with decreasing particle *** highest proportion of Cd in the form distribution of soil was in the bound to iron and manganese oxides,while the maximum proportion of As,Sb and Pb were in the *** optimal solid-liquid ratio of the hydrocyclone was 1:20,and the corresponding separation efficiency and flow rate were 84.7%and 1.76 m^(3)/hr,*** grade efficiency of soil particle separation increases with particle size and exceeds 99%for particles above 1,000μ*** experiments have revealed that oxalic acid(OA)and a combination of oxalic acid and EDTA(OAPE)were more efficient than citric acid(CA)and a combination of citric acid and EDTA(CAPE)for the desorption of heavy metals,*** comparison of OAPE and eddy leaching found that the latter improved the desorption efficiency by 9.4%,7.5%,7.2%and 7.8%for As,Cd,Sb and Pb compared to the former,*** results demonstrated that the eddy leaching technique could further enhance the desorption efficiency of heavy *** is expected to provide technical support for soil remediation with reduced usage of leaching agents.

关键词： Heavy metals Soil remediation Oxalic acid Eddy leaching Hydrocyclone

3D‑Printed Carbon‑Based Conformal Electromagnetic Interference Shielding Module for Integrated Electronics

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Nano-Micro Letters 2024年第5期16卷 87-101页

作者： Shaohong Shi Yuheng Jiang hao Ren Siwen Deng jianping Sun Fangchao Cheng Jingjing Jing Yinghong Chen State Key Laboratory of Featured Metal Materials and Life‑Cycle Safety for Composite Structures School of ResourcesEnvironment and MaterialsGuangxi UniversityNo.100Daxuedong RoadNanning 530004People’s Republic of China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversitySichuan UniversityNo.24 South Section 1Yihuan RoadChengdu 610065People’s Republic of China

Electromagnetic interference shielding(EMI SE)modules are the core com-ponent of modern ***,the tra-ditional metal-based SE modules always take up indispensable three-dimensional space inside electronics,posing a major obstacle to the integra-tion of *** innovation of integrating 3D-printed conformal shielding(c-SE)modules with packaging materials onto core electronics offers infinite possibilities to satisfy ideal SE func-tion without occupying additional ***,the 3D printable carbon-based inks with various proportions of graphene and carbon nanotube nanoparticles are well-formulated by manipulating their rheological ***,the free-constructed architectures with arbitrarily-customized structure and multifunctionality are created via 3D *** particular,the SE performance of 3D-printed frame is up to 61.4 dB,simultaneously accompanied with an ultralight architecture of 0.076 g cm^(-3) and a superhigh specific shielding of 802.4 dB cm3 g^(-1).Moreover,as a proof-of-concept,the 3D-printed c-SE module is in situ integrated into core electronics,successfully replacing the traditional metal-based module to afford multiple functions for electromagnetic compatibility and thermal ***,this scientific innovation completely makes up the blank for assembling carbon-based c-SE modules and sheds a brilliant light on developing the next generation of high-performance shielding materials with arbitrarily-customized structure for integrated electronics.

关键词： 3D printing Carbon-based nanoparticles Conformal electromagnetic interference shielding Integrated electronics

Delineation of urban growth boundary based on FLUS model under the perspective of land use evaluation in hilly mountainous areas

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Journal of Mountain Science 2024年第5期21卷 1647-1662页

作者： ZHANG Yunping LIN jianping HUANG Yimin CHEN Zebin ZHU Chenhui YUAN hao School of Geography and Environmental Engineering Gannan Normal UniversityGanzhou 341000China Key Laboratory of Low Carbon Recycling Technology for Municipal Solid Waste in Jiangxi Province Ganzhou 341000China

With rapid economic development,the size of urban land in China is expanding *** Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control the urban *** delineation of UGB can inhibit the disorderly spread of urban space and guide the normal development of the *** is of practical significance for the construction of green urban *** study utilizes GIS technology to establish a land construction suitability evaluation system for Nankang city,which is experiencing rapid urban expansion,and outlines the preliminary UGB under the future land use simulation(FLUS)*** the same time,considering the coupled coordination of"Production-Living-Ecological Space",and based on the suitability evaluation,we revised the preliminary UGB by combining the advantages of the patch-generating land use simulation(PLUS)model and the convex hull model to delineate the final *** results show that:1)the comprehensive score of the evaluation of the suitability of the construction of land from high to low shows the distribution of the center of the city to the surrounding circle type spread,the center of the city has the highest suitability *** results of convex hull model show that the urban expansion type of Nankang is *** the future,the urban expansion will mainly occur in the northern part of the *** PLUS model predicts an increase of 3359.97 hm^(2)of construction land in Nankang by 2035,of which 2022.97 hm^(2)is urban construction land.2)The FLUS model has a prediction accuracy of 86.3%and delineates a preliminary UGB area of 9215.07 hm^(2).3)We used the results of the construction suitability evaluation,PLUS model simulation results,and convex hull model predictions to revise the originally delineated *** final delineated UGB area is 8895.67 hm^(2)and it is capable of meeting the future development of the study *** results of the delineation can promote

关键词： Urban sprawl FLUS model Spatial correction Urban growth boundary Sustainable development

Research progress of viral sepsis:etiology,pathophysiology,diagnosis,and treatment

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Emergency and Critical Care Medicine 2024年第2期4卷 74-81页

作者： jianping Li Yiqi Luo hao Li Yunhong Yin Yi Zhang Department of Pulmonary and Critical Care Medicine Qilu Hospital of Shandong UniversityJinanShandongChina

Sepsis is a common systemic disease characterized by various physiological and pathological *** can result from infection by various pathogens,such as bacteria,viruses,and *** rate of culture-negative sepsis is almost 42%,indicating that most patients may have nonbacterial *** the outbreak of coronavirus disease 2019,viral sepsis has attracted growing attention because many critically ill patients develop *** sepsis can be caused by viral infections and combined with,or secondary to,bacterial *** the common types of viral sepsis and the main characteristics of its pathogenesis will be helpful for effective diagnosis and treatment,thereby reducing *** identification of the causative agent of viral sepsis can help reduce the overuse of broad-spectrum *** this article,we reviewed the common viruses of sepsis,their potential pathophysiology,targets of diagnosis,and remedies for viral sepsis.

关键词： Acute gastrointestinal injury Acute kidney injury Acute lung injury Cytokine storm Diagnosis Treatment of viral sepsis Viral sepsis