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典型7.62 mm狙击弹对有生目标的杀伤效应

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兵工学报 2024年第9期45卷 2973-2981页

作者：袁瑞温垚珂刘东旭贾益宁聂伟晓夏海龙南京理工大学机械工程学院江苏南京210094 重庆长江电工工业集团有限公司枪弹开发中心重庆401336

为了研究典型7.62 mm狙击弹在不同距离上对有生目标造成的杀伤效应,采用自适应光滑流体动力学方法(Adaptive Smoothed Particle Hydrodynamics,ASPH)构建数值计算模型,获得不同距离上该弹丸对弹道明胶造成的瞬时空腔尺寸,并与相应实验... 详细信息

为了研究典型7.62 mm狙击弹在不同距离上对有生目标造成的杀伤效应,采用自适应光滑流体动力学方法(Adaptive Smoothed Particle Hydrodynamics,ASPH)构建数值计算模型,获得不同距离上该弹丸对弹道明胶造成的瞬时空腔尺寸,并与相应实验结果进行验证;基于自主开发的人体易损性评估软件,获得该狙击弹在200 m、400 m和800 m上命中人体胸部时可能造成的损伤严重度。研究结果表明:ASPH方法兼顾了计算精度和计算效率,适用于求解侵彻大变形问题;相同侵彻速度下攻角大的弹丸在明胶中翻滚更早,受到的加速度作用力更大,靶标厚度对弹丸运动过程和杀伤效果也有着重要影响;2°攻角下,射击距离为200 m时造成的瞬时空腔直径分别为400 m和800 m时的1.14倍和1.44倍;2°攻角下,7.62 mm狙击弹200 m时侵彻初始阶段加速度峰值分别为400 m和800 m时的1.63倍和3.8倍;基于人体易损性评估软件,当射击距离分别为200 m、400 m和800 m时,命中人体胸部剑突右上方情况下造成的最大简明创伤评分分别为6(死亡)、5(危重伤)和4(严重),新损伤严重度评分分别为75、57和48,随着命中距离的增加,人员死亡概率从96.8%下降到60.3%。

关键词：狙击弹弹道明胶瞬时空腔人体易损性评估

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Breaking the energy density limit of Li NiO_(2):Li_(2)NiO_(3)or Li_(2)NiO_(2)?

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Science China Materials 2022年第4期65卷 913-919页

作者： yining jia Yaokun Ye jiahua Liu Shisheng Zheng Weicheng Lin Zhu Wang Shunning Li Feng Pan jiaxin Zheng School of Advanced Materials Peking UniversityShenzhen Graduate SchoolShenzhen518055China Fujian science&technology innovation laboratory for energy devices of China(21C-LAB) Ningde352100China

The development of next-generation layered oxide cathodes for high-energy-density electrical vehicle Li-ion batteries(LIBs)is an urgent *** existing method is achieved by continuously increasing the Ni contents of Ni-based layered oxides,but it has been limited to LiNiO_(2).To break this limit and attain increased energy densities,a promising strategy,which involves the introduction of excess Li ions into transition metal(TM)layers to form Li-excess compounds Li_(2)MO_(3)(M is a TM cation),has attracted enormous interest ***,another strategy,which has been neglected in recent years,involves the insertion of an extra layer of Li ions between the TM and original Li layers to form Li_(2)MO_(2).In this study,typical reversible Li_(2)NiO_(3) and 1T-Li_(2)NiO_(2) were selected as two representative cathodes to break the limit of LiNiO_(2),thereby availing comprehensive comparison with LiNiO_(2) regarding their overall properties as cathodes from a theoretical ***,dissimilar to the Ni^(3+)/Ni^(4+)monoelectron cationic redox associated with LiNiO_(2),a polaronic anionic redox reaction occurs in Li_(2)NiO_(3),while a reversible Ni^(2+)/Ni^(4+)double-electron redox reaction accompanied by insulator-metal transition occurs in Li_(2)NiO_(2).Owing to this double-electron cationic activity,Li_(2)NiO_(2) exhibits absolute advantages over the other two materials(LiNiO_(2) and Li_(2)NiO_(3))as cathodes for LIBs in terms of the capacity,energy density,electronic conductivity,and thermal stability,thus rendering it the most promising candidate for next-generation layered oxide cathodes with high energy densities to break the limit of LiNiO_(2).

关键词： Li-ion battery Li_(2)NiO_(3)and Li_(2)NiO_(2) double-electron redox anionic redox theoretical perspective

CSST Dense Star Field Preparation:A Framework for Astrometry and Photometry for Dense Star Field Images Obtained by the China Space Station Telescope(CSST)

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Research in Astronomy and Astrophysics 2024年第7期24卷 158-169页

作者： yining Wang Rui Sun Tianyuan Deng Chenghui Zhao Peixuan Zhao jiayi Yang Peng jia Huigen Liu Jilin Zhou College of Electronic Information and Optical Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Astronomy&Space Science Nanjing UniversityNanjing 210093China Peng Cheng Lab Shenzhen 518066China

The China Space Station Telescope(CSST)is a telescope with 2 m diameter,obtaining images with high quality through wide-field *** its first observation cycle,to capture time-domain observation data,the CSST is proposed to observe the Galactic halo across different *** data have significant potential for the study of properties of stars and ***,the density of stars in the Galactic center is high,and it is a well-known challenge to perform astrometry and photometry in such a dense star *** paper presents a deep learning-based framework designed to process dense star field images obtained by the CSST,which includes photometry,astrometry,and classifications of targets according to their light curve *** simulated CSST observation data,we demonstrate that this deep learning framework achieves photometry accuracy of 2%and astrometry accuracy of 0.03 pixel for stars with moderate brightness mag=24(i band),surpassing results obtained by traditional ***,the deep learning based light curve classification algorithm could pick up celestial targets whose magnitude variations are 1.7 times larger than magnitude variations brought by Poisson photon *** anticipate that our framework could be effectively used to process dense star field images obtained by the CSST.

关键词： techniques photometric-methods data analysis-astrometry

圆环形燃烧室两相混气旋转爆震波传播过程实验研究

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推进技术 2024年第2期45卷 97-104页

作者：贾冰岳张义宁孟皓潘虎洪延姬航天工程大学激光推进及其应用国家重点实验室北京101416 北京动力机械研究所北京100074

为分析不同燃烧室结构和来流工况对两相混气旋转爆震波传播过程的影响,在圆环形燃烧室内进行了实验研究。获得了不同来流总温T、燃烧室出口堵塞比β以及混气当量比φ对旋转爆震波传播特性的影响,并对典型工况下圆环形燃烧室内旋转爆震... 详细信息

为分析不同燃烧室结构和来流工况对两相混气旋转爆震波传播过程的影响,在圆环形燃烧室内进行了实验研究。获得了不同来流总温T、燃烧室出口堵塞比β以及混气当量比φ对旋转爆震波传播特性的影响,并对典型工况下圆环形燃烧室内旋转爆震波传播频率和切向热声耦合燃烧固有频率进行了计算。结果表明,燃烧室出口堵塞比变小时有利于旋转爆震波的稳定;旋转爆震波传播速度随来流总温和当量比的提高而增加;在两相混气中获得了一种传播速度大幅低于C-J理论值的低速爆震波。

关键词：旋转爆震波两相混气传播速度低速爆震实验研究

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人员易损性评估技术综述

兵器装备工程学报 2023年第3期44卷 19-29页

作者：贾益宁温垚珂董方栋覃彬徐浩然李子轩南京理工大学机械工程学院南京210094 瞬态冲击技术重点实验室北京102202 中国兵器工业第208研究所北京102202

人员易损性是典型的医工交叉领域,在战伤救治和毁伤评估等方面有重大意义。分析了各国构建的基于人体解剖结构的人体易损性模型异同;从动能弹药造成的人体创伤伤道构建、基于AIS(abbreviated injury scale)的人员损伤评估、基于ECV(elem... 详细信息

人员易损性是典型的医工交叉领域,在战伤救治和毁伤评估等方面有重大意义。分析了各国构建的基于人体解剖结构的人体易损性模型异同;从动能弹药造成的人体创伤伤道构建、基于AIS(abbreviated injury scale)的人员损伤评估、基于ECV(elemental capability vector)的失能评估、弹药对人员的杀伤效能评估和单兵防护装备效能评估等5个方面对人员易损性评估技术进行了综述;重点对美国ORCA (operational requirement-based casualty assessment)软件的典型损伤评估模块进行了介绍,并给出3个基于ORCA软件的人员易损性评估应用案例。研究成果可为弹药论证、研制、效能评估和人员战场生存力评估、单兵防护设计与优化等研究提供参考。

关键词：创伤弹道学人员易损性评估软件 ORCA:毁伤评估

不同类型多糖对羊皮明胶凝胶性质及结构的影响

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食品与发酵工业 2024年第10期50卷 112-118,126页

作者：王敏赵以宁余群力韩玲罗进贾培程强甘肃农业大学食品科学与工程学院甘肃兰州730070 泾川县旭康食品有限责任公司甘肃平凉744000

为探究2种不同类型的多糖对羊皮明胶凝胶特性和结构的影响,利用卡拉胶与魔芋胶复配,银耳多糖作为安全性改性剂,研究羊皮明胶凝胶强度、质构、色泽、熔化温度及结构的变化。结果表明,卡拉胶与魔芋胶复配可显著提高羊皮明胶凝胶的凝胶强... 详细信息

为探究2种不同类型的多糖对羊皮明胶凝胶特性和结构的影响,利用卡拉胶与魔芋胶复配,银耳多糖作为安全性改性剂,研究羊皮明胶凝胶强度、质构、色泽、熔化温度及结构的变化。结果表明,卡拉胶与魔芋胶复配可显著提高羊皮明胶凝胶的凝胶强度和质构特性,在复配胶质量比为2∶1时,凝胶强度和硬度最大,分别为(625.75±5.28)g、(172.26±0.5)g。同时,熔化温度提高至30℃以上。加入银耳多糖后,增强了复合凝胶的粘连性。L^(*)值无显著变化,而a^(*)值和b^(*)值显著提高。红外光谱图表明,亲水胶体减少了明胶凝胶分子内氢键的形成。添加银耳多糖使羰基向高波数移动。加入多糖后羊皮明胶衍射峰逐渐变得平坦,三股螺旋和左螺旋的生成被破坏。扫描电镜(scanning electron microscope,SEM)结果表明添加适量多糖后,改善了复合凝胶的网络结构,使得网络结构更加均匀致密。综上所述,卡拉胶与魔芋胶复配主要改善羊皮明胶的质构特性和熔化温度,银耳多糖主要影响明胶凝胶的色泽和粘连性、回弹力。2种多糖都对羊皮明胶的特性产生了积极的影响,这可为以后羊皮明胶在食品上的应用提供理论依据和技术指导。

关键词：羊皮明胶复配胶凝胶强度质构特性

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辽南晚更新世风成沉积序列与古气候意义

第四纪研究 2024年第2期44卷 380-393页

作者：刘亮杨艺凝许姗贾飞飞张威魏东岚柴乐马瑞丰辽宁师范大学地理科学学院辽宁大连116029 东华理工大学地球科学学院江西南昌330013 鞍山师范学院管理学院辽宁鞍山114007

作为中国东部重要的第四纪风成堆积地层,辽南风成沉积反映的气候振荡记录对于揭示区域古气候变化、东亚季风变迁等有着不言而喻的重要性。本研究利用辽南老虎村5.44 m厚的风成沉积剖面作为研究对象,采用光释光(OSL)测年技术建立了研究... 详细信息

作为中国东部重要的第四纪风成堆积地层,辽南风成沉积反映的气候振荡记录对于揭示区域古气候变化、东亚季风变迁等有着不言而喻的重要性。本研究利用辽南老虎村5.44 m厚的风成沉积剖面作为研究对象,采用光释光(OSL)测年技术建立了研究区沉积地层的年代框架,通过岩石学和代用指标重建了晚更新世期间的风成沉积历史。结果表明:风成活动发生在71.7~61.7 ka, 49.4~42.4 ka和约23.0 ka,分别对应深海氧同位素阶段(MIS)5a~4、 3b和2,寒冷干燥的气候条件与增强的东亚冬季风促使风成活动加剧;而MIS 3a和MIS 3c的沉积中断可能受到了暖湿气候的影响。研究区的粒度数据表明在MIS 5/4转变时期有一个短暂的冬季风波动,同时,中值粒径增大可能与海因里希事件(H6、 H5、 H2)有关,未来仍需更多的区域气候纪录来支持这一观点。

关键词：辽南风成沉积气候记录晚更新世海因里希事件

黑曲霉酸性脂肪酶Tgl的酶学性质及其酯化能力研究

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食品与发酵工业 2024年第10期50卷 237-243页

作者：李文瑶陈非凡郑佳刘怡宁杜丽平卢彦坪马立娟天津科技大学生物工程学院天津300457 宜宾五粮液股份有限公司四川宜宾644000

脂肪酶是一种具有水解、酯化、酯交换等多种功能的生物催化剂,为研究脂肪酶的酯化能力,该文克隆表达了来源于黑曲霉的脂肪酶Tgl编码基因,对其进行生物信息学分析,研究该酶的酶学性质及其催化合成脂肪酸乙酯的能力。结果表明,脂肪酶Tgl... 详细信息

脂肪酶是一种具有水解、酯化、酯交换等多种功能的生物催化剂,为研究脂肪酶的酯化能力,该文克隆表达了来源于黑曲霉的脂肪酶Tgl编码基因,对其进行生物信息学分析,研究该酶的酶学性质及其催化合成脂肪酸乙酯的能力。结果表明,脂肪酶Tgl的最适反应温度为50℃,在50℃下孵育12 h后残余酶活力仍能达到70%左右;最适反应pH值为5.0,在pH 5.0条件下孵育12 h后,其相对酶活力为70%。有机试剂对脂肪酶Tgl均表现出不同程度的抑制作用,其中,乙醇对脂肪酶的抑制作用最为明显,但是在40%的乙醇体系下,Tgl的残余酶活力仍接近80%。20%的乙醇体系中,Tgl催化合成乙酸乙酯的产量最高,为41.62 mg/L,而在60%乙醇体系中催化合成己酸乙酯的产量最高,可达171.08 mg/L。由此可见,黑曲霉酸性脂肪酶Tgl具有较高的催化脂肪酸乙酯合成的能力,在酿造工业中具有很大的应用潜力。

关键词：黑曲霉脂肪酶生物信息学分析酶学性质酯化能力

Effect of gender on the association between cumulative cardiovascular risk factors and depression:results from the US National Health and Nutrition Examination Survey

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General Psychiatry 2023年第4期36卷 273-283页

作者： Sen Li Zhaoqi jia Zhang Zhang Yuxin Li yining Ding Zongshi Qin Shuzhen Guo School of Life Sciences Beijing University of Chinese MedicineBeijingChina Peking University Clinical Research Institute Peking UniversityBeijingChina School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijingChina

Background The comorbidity of cardiovascular disease(CVD)and depression has been well established,as depression usually presents simultaneously with CVD risk ***,the potential association between cumulative exposure to CVD risk and depression remains unclear,so we conducted the current *** our knowledge,this is the first study that employs the cumulative risk model to examine the effect of CVD risk factors on depression using nationally representative population and gender,age and CVD status-stratified *** To systematically study the possible individual and cumulative effect of 18 CVD risk factors on *** A cross-sectional,secondary analysis investigated associations between 18 CVD risk factors and *** interaction effect between CVD risk factors and age,gender and CVD status was also *** included 20816 participants from the US National Health and Nutrition Examination Survey 2005–*** with Patient Health Questionnaire-9 scores over 15 or who were using an antidepressant were considered depressive;18 known cardiovascular risk factors were incorporated in the present *** At the individual risk factor level,smoking,drinking,living alone,sleep quality,body mass index,waist circumference and diabetes status had differential associations with depression risk according to the gender,age or CVD status of the *** importantly,gender-stratified cumulative risk analysis indicated that similar depression risk was found in both genders with a small number of CVD risk factors(odds ratio(OR)adjusted=1.32;95%confidence interval(CI):0.87 to 1.99),but females had a significantly higher depression risk compared with males under high cumulative risk exposure(ORadjusted=2.86;95%CI:1.79 to 4.59).Conclusions Clarifying the association of numerous CVD risk factors with depression according to gender,age and overall CVD status may be beneficial for risk stratification and the

关键词： cardiovascular prevention stratified