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爆炸切割网络传爆中的间隙与角度效应

火工品 2025年第1期 37-43页

作者：周晓鹏姜勇袁航中国船舶集团有限公司第七一三研究所河南郑州450015 河南省水下智能装备重点实验室河南郑州450015

为研究爆炸切割网络中传爆节点处传爆能力的关键影响因素,通过改变切割索对传爆药柱的传爆间隙进行了平板传爆试验,将试验结果结合仿真分析确定了JO-11C传爆药柱的仿真材料参数,并进一步分析了传播角度对传爆能力的影响。研究结果表明:... 详细信息

为研究爆炸切割网络中传爆节点处传爆能力的关键影响因素,通过改变切割索对传爆药柱的传爆间隙进行了平板传爆试验,将试验结果结合仿真分析确定了JO-11C传爆药柱的仿真材料参数,并进一步分析了传播角度对传爆能力的影响。研究结果表明:随着传爆间隙的增加,传爆能力下降,切割索对传爆药柱的最大传爆间隙区间为2.0~2.5 mm;同时,传爆角度的增大能够显著提高传爆能力。本研究为爆炸切割网络的传爆性能研究以及提高武器系统的可靠性提供了参考。

关键词：爆炸切割网络传爆间隙传爆角度传爆药柱仿真分析

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Ablation characteristics of insulator under high-temperature gas dual-pulse erosion

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Defence Technology（防务技术） 2022年第10期18卷 1875-1885页

作者： Yang liu xiao-cong Li peng-fei Zhu Kun Xi Northwestern Polytechnical University 710072Xi'anPR China Xi'an Modern Chemistry Research Institute 710065PR China Department of Aerospace Propulsion Technology Science and Technology on CombustionInternal Flow and Thermal-Structure LaboratoryShaanxiPR China

This study numerically simulated and investigated the flow field characteristics of a typical dual-pulse solid rocket motor with a soft pulse separation device through thermal insulation ablation under high-temperature dual-pulse *** ablation rate of ethylene-propylene-diene monomer(EPDM)insulator was measured after the *** results were analyzed through scanning electron microscopy and microcomputed *** ablation mechanism of the EPDM insulator under the operation conditions of a dual-pulse solid rocket motor was evaluated by analyzing the *** results reveal that the internal flow field of the motor with a soft pulse separation device is *** original charred layer existing on the EPDM insulator surface in the first pulse combustor is the decisive factor affecting the final ablation rate of the dual-pulse motor during the second pulse operation,and the ablation characteristic region is easily formed with the exfoliation of the charred *** ablation rate difference of the insulator increases with gas velocity.

关键词： Dual-pulse solid rocket motor High temperature gas Ablation PSD Charred layer

Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying liu Bei peng xiaoyan Zhou Lixia Qin Lingyan Liang Yichen Wei Qingping Zhang xiaocheng Li Haixia Qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao Jun liu Jianrong Yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

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湖北省高职院校图书馆服务现状调查分析

武汉职业技术学院学报 2018年第3期17卷 33-37页

作者：代彬彭肖红刘想容胡庆红长江职业学院图书馆湖北武汉430074

图书馆服务问卷调查是图书馆与读者沟通与交流的重要方式和手段,是提高读者读者服务满意度的参考依据。从图书馆的馆藏资源建设、环境建设、服务评价等方面,对湖北省5所高职院校读者进行抽样问卷调查。针对调查中读者反映的图书更新慢... 详细信息

图书馆服务问卷调查是图书馆与读者沟通与交流的重要方式和手段,是提高读者读者服务满意度的参考依据。从图书馆的馆藏资源建设、环境建设、服务评价等方面,对湖北省5所高职院校读者进行抽样问卷调查。针对调查中读者反映的图书更新慢、标识设置不明显、硬件环境欠佳、开馆时间受限、馆员服务意识和职业素养不高等问题,提出优化馆藏资源建设、创建良好阅览环境、提升馆员素质、拓展服务能力、完善规章制度建设等改进建议。

关键词：高职图书馆问卷调查服务评价策略研究

Impact of polarization switching on the effective carrier mobility of HfZrOx ferroelectric field-effect transistor

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Science China(Information Sciences) 2023年第6期66卷 305-306页

作者： Fenning liu Yue peng Wenwu xiao Yan liu xiao YU Genquan HAN School of Microelectronics Xidian University Research Center for Intelligent Chips Xi'an UniIC Semiconductors Hangzhou Institute of Technology Xidian University

Doped-HfO2ferroelectrics have attracted tremendous research interest for non-volatile memory and memory-incomputing applications due to their CMOS compatibility,advantages of non-destructive reading,and low power cons... 详细信息

关键词： Zirconium compounds

Oracle Inequality for Sparse Trace Regression Models with Exponentialβ-mixing Errors

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Acta Mathematica Sinica,English Series 2023年第10期39卷 2031-2053页

作者： Ling peng Xiang Yong TAN Pei Wen xiao Zeinab RIZK xiao Hui liu School of Statistics and Data Science Jiangxi University of Finance and EconomicsNanchang 330013P.R.China Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang 330013P.R.China

In applications involving,e.g.,panel data,images,genomics microarrays,etc.,trace regression models are useful *** address the high-dimensional issue of these applications,it is common to assume some sparsity *** the case of the parameter matrix being simultaneously low rank and elements-wise sparse,we estimate the parameter matrix through the least-squares approach with the composite penalty combining the nuclear norm and the *** extend the existing analysis of the low-rank trace regression with *** to exponentialβ-mixing *** explicit convergence rate and the asymptotic properties of the proposed estimator are ***,as well as a real data application,are also carried out for illustration.

关键词： Trace regression model low-rank matrix oracle inequality exponentialβ-mixing errors

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Lipomatous ependymoma with ZFTA:RELA fusion-positive:A case report

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World Journal of Clinical Cases 2025年第1期13卷 48-55页

作者： xiao-Yu Zhao Juan-Han Yu Yi-Hua Wang Yi-Xin liu Lu Xu Lin Fu Ning Yi China Medical University The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Department of Pathology The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Anshan Cancer Hospital Anshan 114000Liaoning ProvinceChina

BACKGROUND Ependymoma with lipomatous differentiation is a rare type of *** ZFTA fusion-positive supratentorial ependymoma is a novel tumor type in the 2021 World Health Organization classification of central nervous system *** fusion-positive lipomatous ependymoma has not been reported to *** SUMMARY We reported a case of a 15-year-old Chinese male who had a sudden convulsion lasting approximately six *** resonance imaging showed a round cystic shadow of approximately 1.9 cm×1.5 cm×1.9 cm under the right parieto-occipital *** examination showed characteristic perivascular pseudorosettes and adipose differentiation in the ***-chemical staining showed that the tumor cells were negative for cytokeratin,NeuN,Syn and p53,but positive for GFAP,vimentin and S-100 ***-ficant punctate intracytoplasmic EMA immunoreactivity was *** level of Ki-67 was about 5%.Genetic analysis revealed ZFTA:RELA fusion.A cranio-tomy with total excision of the tumor was *** follow-up time was 36 months,no evidence of disease recurrence was found in magnetic resonance *** Based on these findings,the patient was diagnosed as a ependymoma with ZFTA fusion and lipomatous *** case report provides information on the microscopic morphological features of ependymoma with ZFTA fusion and lipomatous differentiation,which can help pathologists to make a definitive diagnosis of this tumor.

关键词： Ependymoma Lipomatous Molecular classification Supratentorial ZFTA:RELA fusion Case report

Experimental Research on a Feasible Building Insulation Material Based Reed in China

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Journal of Thermal Science 2025年第1期 176-187页

作者： liu Tiantian peng Yizhe liu Lifang CAI Chenghan WANG Shuang LI Hongqiang College of Civil Engineering Hunan University College of Civil Engineering Hunan University of Science and Technology School of Energy and Power Jiangsu University of Science and Technology National Center for International Research Collaboration in Building Safety and Environment (NCIRCBSE) Hunan University Key Laboratory of Building Safety and Energy Efficiency of the Ministry of Education Hunan University

The seemingly useless reeds are prepared as thermal insulation materials,which not only meet the requirements of environmental sustainability but also enhance the added value of reeds,creating new economic *** hydrophobicity of raw biomass surfaces leads to problems such as weak bonding strength and non-dense structure in the formed materials,as well as issues related to the residual insect infestations on the *** this study,reed straw was used as the raw material,and foamed geopolymer was used as the binder to prepare building insulation materials based *** improve the interfacial adhesion performance between reed straw and foamed geopolymer,a thermochemical modification method-thermal carbonization,was *** this study,the mechanical properties and hydraulic properties of the studied materials with different degrees of surface thermal modification were tested,especially the fire resistance performance,and weathering resistance performance rarely found in published *** the surface thermal modification condition of reed straw was 250℃（30 min）,the comprehensive performance of reed-based building insulation materials was the best,when the studied material density was 321.3 kg/m3;the compressive strength was 0.59 MPa;the thermal conductivity was 0.101 W/（m·K）;the pH was 11.27;the moisture absorption rate was 25.1%,and the compressive strength loss rate in wet-dry cycles was 18.5%.In addition,it had excellent fire resistance performance and weathering resistance *** new material can be widely used to improve the thermal insulation of traditional buildings and as sandwich filler in prefabricated buildings,such as preparing insulating walls.

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胰腺疾病体外细胞模型研究进展

中国药理学通报 2025年第1期41卷 23-29页

作者：朱卫丰彭立军刘婧彭淑红江西中医药大学现代中药制剂教育部重点实验室 2.江西中医药大学药学院3.江西中医药大学中医基础理论分化发展研究中心4.江西省中医病因生物学重点实验室江西南昌330004

不健康的饮食、吸烟、饮酒会引起多种胰腺疾病,包括胰腺炎、糖尿病和胰腺癌等,严重威胁人体健康。构建体外细胞模型在研究胰腺疾病的病因病机及其药物的开发及筛选中具有重要意义。目前,国内外学者已开发出多种体外胰腺疾病模型。该文... 详细信息

不健康的饮食、吸烟、饮酒会引起多种胰腺疾病,包括胰腺炎、糖尿病和胰腺癌等,严重威胁人体健康。构建体外细胞模型在研究胰腺疾病的病因病机及其药物的开发及筛选中具有重要意义。目前,国内外学者已开发出多种体外胰腺疾病模型。该文概括了常见胰腺疾病的体外细胞模型,并从模型细胞的特性、培养方式、造模方式、评价指标等方面进行综述,以期为胰腺疾病相关研究人员提供参考。

关键词：胰腺疾病细胞模型细胞特性培养方式造模方法评价指标