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An efficient and accurate numerical method for simulating close-range blast loads of cylindrical charges based on neural network

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Defence Technology(防务技术) 2025年第2期44卷 257-271页

作者： Ting liu Changhai Chen han li Yaowen Yu Yuansheng Cheng School of Naval Architecture and Ocean Engineering Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Naval Architecture and Ocean Engineering Hydrodynamics Wuhan 430074China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240China

To address the problems of low accuracy by the CONWEP model and poor efficiency by the Coupled Eulerian-Lagrangian(CEL)method in predicting close-range air blast loads of cylindrical charges,a neural network-based simulation(NNS)method with higher accuracy and better efficiency was *** NNS method consisted of three main ***,the parameters of blast loads,including the peak pressures and impulses of cylindrical charges with different aspect ratios(L/D)at different stand-off distances and incident angles were obtained by two-dimensional numerical ***,incident shape factors of cylindrical charges with arbitrary aspect ratios were predicted by a neural ***,reflected shape factors were derived and implemented into the subroutine of the ABAQUS code to modify the CONWEP model,including modifications of impulse and *** reliability of the proposed NNS method was verified by related experimental *** accuracy improvement was acquired by the proposed NNS method compared with the unmodified CONWEP ***,huge efficiency superiority was obtained by the proposed NNS method compared with the CEL *** proposed NNS method showed good accuracy when the scaled distance was greater than 0.2 m/kg^(1/3).It should be noted that there is no need to generate a new dataset again since the blast loads satisfy the similarity law,and the proposed NNS method can be directly used to simulate the blast loads generated by different cylindrical *** proposed NNS method with high efficiency and accuracy can be used as an effective method to analyze the dynamic response of structures under blast loads,and it has significant application prospects in designing protective structures.

关键词： Close-range air blast load Cylindrical charge Numerical method Neural network CEL method CONWEP model

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Confined metal-acid units for boosting benzene hydroalkylation via efficient activation of key intermediate

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Nano Research 2025年第2期18卷 193-205页

作者： Jianpeng li Kaihang Sun Jinyu Huang Yongheng Jia Shufang Zhao Young Dok Kim li han Baojun li Jie Feng Zhongyi liu Zhikun Peng College of Chemistry Henan Institutes of Advanced TechnologyCollege of Ecology and EnvironmentState Key Laboratory of Coking Coal Resources Green ExploitationZhengzhou UniversityZhengzhou 450001China Department of Chemistry Sungkyunkwan UniversitySuwon 16419Republic of Korea

Precisely *** micro-nanoscale characteristics and synergistic effect of metal-acid sites to regulate the distribution of hydroconversion products are significant but *** protonated carbocation intermediates triggered by tandem reaction on metal-acid region hinder target product formation due to their high reactivity and *** M/Zeolite hydroconversion catalysts,which often excel in simple synthesis,ease of separation and ***,they usually consist of sterically unconstrained metal centers which are isolated from acid sites,only providing limited coupling-selectivity to target ***,metal nanoparticles enveloped in acidic zeolite frameworks were developed and used for investigating the process of hydroalkylation of benzene to *** show that appropriate metal encapsulation comprising adequate efficient metal-acid units successfully avoids the more thermodynamically favorable hydrogenation of cyclohexene to cyclohexane,but steers to alkylation of cyclohexene with benzene to *** resulted in the highest cyclohexylbenzene yield of 47.7%among the reported work,and surpassed the performance of all supported M/Zeolite *** and theoretical results supported that the abundant bifunctional metal-acid units enhance the activation frequency and probability of intermediate *** work might provide insights for the integration strategy of dual active site and guidance for the construction of efficient"metal-acid balance"in tandem reactions.

关键词： tandem reaction benzene hydroalkylation metal-acid balance metal encapsulation intermediate transformation

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Active traveling wave vibration control of elastic supported conical shells with smart micro fiber composites based on the differential quadrature method

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Applied Mathematics and Mechanics(English Edition) 2025年第2期46卷 305-322页

作者： Yuxin HAO Lei SUN Wei ZhanG han li College of Mechanical Engineering Beijing Information Science and Technology University Department of Mechanics Guangxi University

This paper investigates the active traveling wave vibration control of an elastic supported rotating porous aluminium conical shell (CS) under impact *** smart materials in the form of micro fiber composites (MFCs) are used as actuators and sensors. To this end, a metal pore truncated CS with MFCs attached to its surface is considered. Adding artificial virtual springs at two edges of the truncated CS achieves various elastic supported boundaries by changing the spring stiffness. Based on the first-order shear deformation theory (FSDT), minimum energy principle, and artificial virtual spring technology, the theoretical formulations considering the electromechanical coupling are derived. The comparison of the natural frequency of the present results with the natural frequencies reported in previous literature evaluates the accuracy of the present approach. To study the vibration control, the integral quadrature method in conjunction with the differential quadrature approximation in the length direction is used to discretize the partial differential dynamical system to form a set of ordinary differential equations. With the aid of the velocity negative feedback method, both the time history and the input control voltage on the actuator are demonstrated to present the effects of velocity feedback gain, pore distribution type, semi-vertex angle, impact loading, and rotational angular velocity on the traveling wave vibration control.

关键词： rotating conical shell (CS) porous metal material active vibration control elastic support differential quadrature method TB123

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Smoke and NO_(x)emission characteristics of in-use construction machinery base on substantial field measurement:A case study in Beijing,China

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Journal of Environmental Sciences 2025年第3期149卷 386-393页

作者： Huawei Yi Yangyang Cui lijun Zhu Yan Shen han li Guanghan Huang linzhen Qu Dongdong Guo Lei Nie Yifeng Xue National Engineering Research Center of Urban Environmental Pollution Control Beijing Municipal Research Institute of Eco-Environmental ProtectionBeijing 100037China Beijing Vehicle Emission Management Affairs Centre Beijing 100176China

To understand the smoke level and NO_(x)emission characteristics of in-use construction machinery in Beijing,we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission level of smoke and NO_(x).The exhaust smoke level and excessive emission situation of different machinery types were identified,and their NO_(x)emission levels were monitored according to the free acceleration *** investigated the correlation of NO_(x)and smoke emission,and proposed suggestions for controlling pollution discharge from construction machinery in the *** results show that the exhaust smoke level was 0–2.62 m^(−1),followed a log-normal distribution(μ=-1.73,δ=1.09,R^(2)=0.99),with a 5.64%exceedance *** observed amongmachinery types,with low-power engine forklifts showing higher smoke *** NO_(x)emission range was 71–1516 ppm,followed a normal distribution(μ=565.54,δ=309.51,R^(2)=0.83).Differences among machinery types were relatively *** rated net power had the most significant impact on NO_(x)***,NO_(x)emissions from construction machinery need further ***,we found a weak negative correlation(p<0.05)between the emission level of smoke and NO_(x),that is the synergic emission reduction effect is poor,emphasizing the need for NO_(x)emission *** the future,the oversight in Beijing should prioritize phasing out ChinaⅠand ChinaⅡmachinery,and monitor emissions from highpower engine ChinaⅢmachinery.

关键词： Fuel-oil construction machinery Smoke NO_(x) Emission level Regulatory suggestion

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Trends of alkaline phosphatase to prealbumin ratio in patients with hepatitis B linked to hepatocellular carcinoma development

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World Journal of Gastroenterology 2025年第2期31卷 42-51页

作者： Wen-Chong Zhen Jing Sun Xue-Ting Bai Qian Zhang Zi-han li Yi-Xin Zhang Rong-Xuan Xu Wei Wu Zhi-han Yao Chun-Wen Pu Xiao-Feng li School of Public Health Dalian Medical UniversityDalian 116044Liaoning ProvinceChina Graduate School Dalian Medical UniversityDalian 116044Liaoning ProvinceChina Dalian Public Health Clinical Center Dalian Municipal Research Institute for Public HealthDalian 116001Liaoning ProvinceChina Department of Epidemiology and Health Statistics Dalian Medical UniversityDalian 116044Liaoning ProvinceChina

BACKGROUND Chronic hepatitis B often progresses silently toward hepatocellular carcinoma(HCC),a leading cause of mortality *** detection of HCC is crucial,yet *** To investigate the role of dynamic changes in alkaline phosphatase to prealbumin ratio(APR)in hepatitis B progression to *** Data from 4843 patients with hepatitis B(January 2015 to January 2024)were *** incidence rates in males and females were compared using the log-rank *** were evaluated using Kaplan–Meier *** linear Mixed-Effects Model was applied to track the fluctuation of APR levels over ***,Joint Modeling of Longitudinal and Survival data was employed to investigate the temporal relationship between APR and HCC *** The incidence of HCC was higher in *** ensure the model’s normality assumption,this study applied a logarithmic transformation to APR,yielding *** levels were higher in females(t=5.26,Pline APR link,rising APR indicates a higher HCC risk.

关键词： Alkaline phosphatase to prealbumin ratio Chronic hepatitis B patients Hepatocellular carcinoma Retrospective cohort study linear Mixed-Effect Mode Joint Modelling of Longitudinal and Survival data

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A cellulose-based lithium-ion battery separator with regulated ionic transport and high thermal stability for extreme environments

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Nano Research 2025年第1期18卷 315-322页

作者： Kun-Peng Yang Song Xie Zi-Meng han Hao-Cheng liu Chong-han Yin Wen-Bin Sun Zhang-Chi ling Huai-Bin Yang De-han li Qing-Fang Guan Shu-Hong Yu Department of Chemistry New Cornerstone Science LaboratoryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsDivision of Nanomaterials&ChemistryHefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

Separators play a critical role in lithium-ion ***,the restrictions of thermal stability and inferior electrical performance in commercial polyolefin separators significantly limit their applications under harsh ***,we report a cellulose-assisted self-assembly strategy to construct a cellulose-based separator massively and *** an ultrahigh ionic conductivity in electrolytes of 3.7 mS·cm^(-1) and the ability to regulate ion transport,the obtained separator is a promising alternative for high-performance lithium-ion *** addition,integrated with high thermal stability,the cellulose-based separator endows batteries with high safety at high temperatures,greatly expanding the application scenarios of energy storage devices in extreme environments.

关键词： lithium-ion batteries bio-inspired materials battery separators cellulose nanofiber ultrahigh ionic conductivity high safety

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Spectrum of thalassemia mutations in fetuses of han and li ethinicities in Hainan province, China

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Asian Pacific Journal of Tropical Medicine 2019年第12期12卷 537-544页

作者： Chao liang Xue-yin Chen Xue Gao Hong-jian Chen Ying-xia Jin Yao Zhou Ming-hong li Wen-cong Wang Wei-ying Lu Yuan-huaHuang Jun Wang Qi li Yan-lin Ma Hainan Provincial Key Laboratory for Human Reproductive Medicine and Genetic Research the First Affiliated Hospital of Hainan Medical UniversityHainan Medical UniversityHaikouHainan 570102China Hainan Provincial Clinical Research Center for Thalassemia the First Affiliated Hospital of Hainan Medical UniversityHaikouHainan 570102China Prenatal Diagnosis Center the First Affiliated Hospital of Hainan Medical UniversityHainan Medical UniversityHaikouHainan 570102China Key Laboratory of Tropical Translational Medicine of Ministry of Education Hainan Medical UniversityHaikouHainan 571199China Texas Heart Institute 6770 Bertner AvenueMC 2-255HoustonTX 77030USA

Objective: To analyze the frequency and spectrum of thalassemia mutations in amniotic fluid samples collected from han and li people in Hainan province of ***: We carried out a retrospective analysis on prenatal diagnosis of amniotic fluid samples collected from pregnant women who may have next generation with high risks of medium or severe thalassemia between 2005 and 2016. Diverse fetal thalassemia genotypes and mutated alleles in han and li people were analyzed and cmpared. Results: We examined 536 amniotic fluid samples from han people and 588 from li people, among which 406 han and 500 li samples were found to carry at least one thalassemia gene mutation, with a detection rate of 75.75% and 85.03%, respectively. Among all α-and β-thalassemia mutant alleles detected, the most frequently found mutations in han and li samples were SEA-type of α-thalassemia and 41/42(–CTTT) of β-thalassemia, respectively. A total of 75 severe thalassemia cases were identified in han samples and 53 in li samples. In most of these severe cases, parents chose to terminate pregnancy after being informed of thalassemia-related risks. Conclusions: The thalassemia mutations shows ethnic and area specificity, and that prenatal diagnosis for high-risk thalassemia carrier pregnant women is an efficient approach to prevent and control the occurrence of severe thalassemia in the high-prevalence areas.

关键词： Thalassemia Prenatal diagnosis Genetic diagnosis Amniotic fluid Genetic counseling

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苏州某污水处理厂GHG排放综合分析及减排路径

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环境科学 2025年第1期46卷 118-128页

作者：黄来来郜龙威李瀚翔李祎頔李勇苏州科技大学环境科学与工程学院苏州215011 江苏省环境科学与工程重点实验室苏州215011

以江苏省苏州市某生活污水处理厂为例,采用碳元素平衡法和排放因子法核算了污水处理系统中产生的温室气体(GHG)排放量.采用生命周期评价法、成本效益法和数据包络分析模型对污水处理厂不同处理单元的环境影响和经济性作出分析,并提出减... 详细信息

以江苏省苏州市某生活污水处理厂为例,采用碳元素平衡法和排放因子法核算了污水处理系统中产生的温室气体(GHG)排放量.采用生命周期评价法、成本效益法和数据包络分析模型对污水处理厂不同处理单元的环境影响和经济性作出分析,并提出减排路径.结果表明,苏州某生活污水处理厂GHG排放总量(以CO_(2)计)为6653.08 kg·(104 m^(3))^(−1),其中直接、间接GHG排放量分别占29.22%和74%,尾水回用实现了3.3%的减排.生物处理阶段和污泥处理阶段为苏州某污水处理厂GHG排放源的主要影响环节,其中生物处理阶段中的大功率设备鼓风机消耗的电力和污泥处理阶段中聚合硫酸铁药剂的使用是GHG排放的主要因素.由生命周期评价分析可知,污水厂的电耗、直接排放的CO_(2)、出水的污染物浓度以及化学药剂的使用会对全球变暖、大气酸化和水体富营养化产生负面影响.经计算,污水处理厂每处理10000 m^(3)的污水可获得13630元的净效益,但2023年4~5月污水处理厂的规模效益小于1,表明期间污水厂产出增加的比例少于投入增加的比例,投入产出的结构不合理.6月份后通过提高整体运行负荷,推进技术改进和管理工作,实现了规模效益的最优化.苏州某生活污水处理厂可通过安装高效能的泵和风机、利用太阳能光伏和水源热泵系统、工艺改进等措施实现污水处理厂“绿色低碳”的目标.

关键词：污水处理厂温室气体(GHG) 环境影响经济性减排路径

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近红外光谱用于DMSO衍生物抗冻过程中水结构分析

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高等学校化学学报 2025年第2期46卷 46-52页

作者：梁繁繁韩丽蔡文生邵学广南开大学化学学院分析科学研究中心天津市生物传感与分子识别重点实验室药物化学生物学国家重点实验室天津300071

采用近红外光谱结合化学计量学方法,研究了二甲基亚砜衍生物L-蛋氨酸亚砜[L-Met(O)-OH]抑制冰晶生长的分子机理.通过小波包变换获得高分辨光谱,对−5℃下不同浓度L-Met(O)-OH溶液在结冰过程中的近红外光谱进行分析,提取出L-Met(O)-OH中S=... 详细信息

采用近红外光谱结合化学计量学方法,研究了二甲基亚砜衍生物L-蛋氨酸亚砜[L-Met(O)-OH]抑制冰晶生长的分子机理.通过小波包变换获得高分辨光谱,对−5℃下不同浓度L-Met(O)-OH溶液在结冰过程中的近红外光谱进行分析,提取出L-Met(O)-OH中S=O基团与冰相互作用的光谱信息,结果表明,L-Met(O)-OH有效抑制冰晶生长的主要原因是S=O基团与冰之间形成的氢键.进一步在0℃条件下分析了不同浓度L-Met(O)-OH溶液的高分辨光谱,发现水分子与L-Met(O)-OH中的S=O和C=O基团相互作用的光谱特征,在结冰过程中,这些相互作用的光谱峰强度逐渐降低,表明S=O和C=O基团与水分子的相互作用减弱,并且在高浓度下减弱效果更加明显.最后,进一步研究了NH基团在抑制冰晶生长过程中发挥的作用,发现在结冰过程中NH基团与水分子的结合逐渐增加,形成了稳定的氢键网络,这表明NH基团在整个结冰过程中始终与水保持相互作用,而不与冰发生显著相互作用.

关键词：近红外光谱 L-蛋氨酸亚砜抑制冰晶生长氢键

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数智化子公司分工、本地聚集与上市公司绩效提升

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河南社会科学 2025年第2期33卷 89-102页

作者：逯建李涵王骁南京大学长江产业发展研究院江苏南京210093 中国移动研究院用户与市场所北京100053

企业数智化转型是企业数字化改造后又一发展方向。通过对数智化进行概括定义,利用数智化行业二位代码精准识别数智化公司,创新性地提出以企业是否设立数智化子公司为企业数智化转型的新判断标准,并据此统计数智化子公司占母公司所有子... 详细信息

企业数智化转型是企业数字化改造后又一发展方向。通过对数智化进行概括定义,利用数智化行业二位代码精准识别数智化公司,创新性地提出以企业是否设立数智化子公司为企业数智化转型的新判断标准,并据此统计数智化子公司占母公司所有子公司比例。利用CNRDS数据库中2000—2021年长三角区域上市公司数据进行实证分析。研究发现,数智化子公司分工程度越高的上市公司,其绩效提升越多,而在研究调节效应时发现,企业周围分布过于密集的数智化子公司会削弱此正向影响,若公司处于成长期则会放大该促进作用。在异质性分析上,主效应对于设立在二线城市的企业、自身为非数智化的企业以及民营企业更为显著。通过研究对推动我国公司从数字化向数智化的转变,促进产业向更高质量发展能提供若干参考建议。

关键词：数智化子公司分工公司绩效企业周期本地聚集

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