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Diagnosis of indirectly driven double shell targets with point-projection hard x-ray radiography

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Matter and Radiation at Extremes 2024年第2期9卷 50-62页

作者： Chao Tian Minghai Yu Lianqiang shan Fengjuan Wu Bi Bi Qiangqiang Zhang Yuchi Wu Tiankui Zhang Feng Zhang Dongxiao Liu Weiwu Wang Zongqiang Yuan Siqian Yang Lei Yang Zhigang deng Jian Teng Weimin Zhou Zongqing Zhao Yuqiu Gu Baohan Zhang Science and Technology on Plasma Physics Laboratory Laser Fusion Research CenterChina Academy of Engineering PhysicsMianyang 621900People’s Republic of China Joint Laboratory for Extreme Conditions Matter Properties Southwest University of Science and TechnologyMianyang 621010People’s Republic of China IFSA Collaborative Innovation Center Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on the upgraded SG-II laser facility. Then, based on thepoint-projection hard x-ray radiography technique, time-resolved radiography of the double shell targets, including that of their near-peakcompression, were obtained. The backlighter source was created by the interactions of a high-intensity short pulsed laser with a metalmicrowire target. Images of the target near peak compression were obtained with an Au microwire. In addition, radiation hydrodynamicsimulations were performed, and the target evolution obtained agrees well with the experimental results. Using the radiographic images, arealdensities of the targets were evaluated.

关键词： double projection point

从“数据隐私框架”看欧美数据跨境流动的规则博弈

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太平洋学报 2024年第1期32卷 44-56页

作者：单文华邓娜西安交通大学陕西西安710049

欧美《隐私盾协议》失效后,双方为了恢复数据跨境流动秩序,于2022年底达成了“数据隐私框架”。该框架旨在回应欧盟法院在“《隐私盾协议》无效案”中提出的主要关切。2023年7月,欧盟委员会基于该框架对美国的个人数据保护水平发布了充... 详细信息

欧美《隐私盾协议》失效后,双方为了恢复数据跨境流动秩序,于2022年底达成了“数据隐私框架”。该框架旨在回应欧盟法院在“《隐私盾协议》无效案”中提出的主要关切。2023年7月,欧盟委员会基于该框架对美国的个人数据保护水平发布了充分性认定决议。然而,该框架并未对美国情报机构大规模收集数据与窥探隐私的行为施加实质性限制。此外,框架建立的双层救济机制由于缺乏独立性,也无法给数据隐私权益受损的欧盟公民提供充分有效的救济。与《隐私盾协议》相比,该框架在本质上并没有明显的突破。欧盟和美国在双方数据跨境流动制度安排上的博弈,表面上是两种数据保护理念和治理模式的碰撞,实际上反映出了欧盟实施“数字主权”战略与美国维护“数字霸权”地位之间存在的根本利益冲突。欧美凭借各自优势,在数字经济时代争夺全球数字治理话语权。通过深入研究欧美之间关于“数据隐私框架”的规则博弈,可以为我国在选择适合本土的数据监管模式和提升数据治理规则话语权方面提供重要的思考和启示。

关键词：《隐私盾协议》数据跨境流动 “数据隐私框架” 充分性认定决议数字主权数字霸权

Central Asia revealed as a key area in evolution of Eremurus (Asphodelaceae)

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Plant Diversity 2024年第3期46卷 333-343页

作者： Dilmurod Makhmudjanov Sergei Volis Ziyoviddin Yusupov Inom Juramurodov Komiljon Tojibaev Tao deng Hang Sun CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina Yunnan International Joint Laboratory for Biodiversity of Central Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina Institute of Botany Academy Sciences of UzbekistanTashkent 100125Uzbekistan University of Chinese Academy of Sciences Beijing 100864China

Eremurus was described at the beginning of the 19th century.However,due to limited sampling and the small number of gene markers to date,its phylogeny and evolution are largely unknown.In this study,we analyzed plastomes from 27 species belonging to 2 subgenera and 3 sections of Eremurus,which are found in Central Asia(its center of diversity)and China.We also analyzed nuclear DNA ITS of 33 species,encompassing all subgenera and sections of the genus in Central Asia,southwest Asia and China.Our findings revealed that the genus was monophyletic,although both subgenera Eremurus and Henningia were found to be paraphyletic.Both plastome and nrDNA-based phylogenetic trees had three clades that did not reflect the current taxonomy of the genus.Our biogeographical and time-calibrated trees suggest that Eremurus originated in the ancient Tethyan area in the second half of the Eocene.Diversification of Eremurus occurred from the early Oligocene to the late Miocene.Paratethys Sea retreat and several orogenetic events,such as the progressive uplift of the Qinghai-Tibet Plateau and surrounding mountain belts(Altai,Pamir,Tian shan),caused serious topographic and climate(aridification)changes in Central Asia that may have triggered a split of clades and speciation.In this transformed Central Asia,speciation proceeded rapidly driven mainly by vicariance caused by numerous mountain chains and specialization to a variety of climatic,topographic and soil conditions that exist in this region.

关键词： Asphodelaceae Asphodeloideae Plastome Central Asia Qinghai-Tibet Plateau

Effects of the Tensile and Shear Properties of Bolts on the Shear Properties of Bolted Rock Joints

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Journal of Earth Science 2022年

作者： Chenlu Wang Luobin Zheng Liangqing Wang Linfeng Zhu shanbai Wu shan deng Faculty of Engineering China University of Geosciences

The mechanical properties of bolts are important factors affecting the shear behavior of bolted joints. In this study, tensile and pure shear tests were conducted on five kinds of bolts made from different materials to measure their tensile and shear parameters. Direct shear tests were conducted to analyze the effects of tensile and shear strength parameters on the shear behavior of bolted joints.The test results showed that the mechanical properties of bolts made from different materials were clearly different and that these differences mainly affected the plastic deformation stage of the bolted joints. The larger the bolt elongation was, the larger the joint shear displacement at bolt failure. The tensile and shear strengths of the bolts were positively correlated with the shear strength of the bolted joints. According to the standard regression analysis, the bolt shear strength had a greater influence than the bolt tensile strength on the bolt contributions when the bolts were perpendicular to the joint surface. Based on the empirical equation for the bolt contribution proposed by Spang, the maximum shear loads in the pure shear test were introduced, and a new equation was established to predict the contributions of bolts. The prediction results obtained using the modified equation were in good agreement with the experimental results.

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Efficacy of intrauterine balloon stent or oral estrogen on prevention of adhesion after transcervical resection of septum in septate uterus:Study protocol for a randomized controlled multicenter study in China

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Chinese Medical Journal 2023年第24期136卷 3016-3018页

作者： shan deng Zichen Zhao Limin Feng Xiaowu Huang Sumin Wang Xiang Xue Lei Yan Baorong Ma Lijuan Hao Xueying Li Lihua Yang Lan Zhu Department of Obstetrics and Gynecology National Clinical Research Center for Obstetric&Gynecologic DiseasesPeking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Obstetrics and Gynecology Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China Department of Hysteroscopic Center Fuxing HospitalCapital Medical UniversityBeijing 100038China Nanjing Maternity and Child Health Care Hospital Jiangsu Province 210004China The Second Affiliated Hospital of Xi’an Jiaotong University Shanxi Province 710004China Center for Reproductive Medicine Cheeloo College of MedicineShandong UniversityShandong Province 250012China Tianjin Central Hospital of Obstetrics and Gynecology Tianjin 300199China Chongqing Health Center for Women and Children Chongqing 401147China Hunan Provincial Maternal and Child Health Care Hospital Hunan Province 410008China Tangshan Maternal and Child Health Care Hospital Hebei Province 063000China

To the Editor:The septate uterus is the most common uterine anomaly and is associated with an increased risk of adverse reproductive outcomes.Transcervical resection of septum(TCRS)is widely performed in patients with adverse reproductive outcomes.The incidence of de novo intrauterine adhesions(IUAs)after TCRS is approximately 5%to 25%.[1]Various anti-adhesion methods are widely used in the clinical management of patients with septate uteri,including intrauterine devices,Foley balloons,estrogen,antibiotics,and hyaluronic acid gel.However,insufficient evidence supports or opposes any of these methods(Level C),[2]lacking high-grade evidence.

关键词： prevention septum after

裂纹长度对PBX代用材料表观断裂韧性Kc的影响

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含能材料 2024年第5期32卷 528-536页

作者：单骏鹏王山邓鹏飞唐维文乾乾中国工程物理研究院化工材料研究所四川绵阳621999

表观断裂韧性(Kc)是表征高聚物粘结炸药(PBX)抵抗裂纹萌生和裂纹扩展的重要材料性能,研究表观断裂韧性Kc的尺寸效应对预测不同尺度的PBX的起裂及失效行为具有重要意义。通过中心裂纹巴西圆盘(CSTBD)试验,对PBX代用材料的表观断裂韧性Kc... 详细信息

表观断裂韧性(Kc)是表征高聚物粘结炸药(PBX)抵抗裂纹萌生和裂纹扩展的重要材料性能,研究表观断裂韧性Kc的尺寸效应对预测不同尺度的PBX的起裂及失效行为具有重要意义。通过中心裂纹巴西圆盘(CSTBD)试验,对PBX代用材料的表观断裂韧性Kc的尺寸效应特性进行研究,通过断裂试验研究了不同裂纹长度(2,4,6,8,10 mm)对CSTBD试样表观断裂韧性Kc的影响。并采用了传统的最大切应力(MTS)准则以及考虑Willimas级数高阶项系数和断裂扩展区(FPZ)长度预估模型的修正最大切应力(MMTS)准则,对PBX代用材料的表观断裂韧性Kc的尺寸效应解释。结果发现,随着裂纹长度的增加,Kc从0.139 MPa·m0.5增长至0.251 MPa·m0.5,并且随着裂纹长度的增加Kc趋于稳定。在使用A3项修正的FPZ长度预估模型下,相较于传统的MTS准则,使用MMTS准则能够很好地解释PBX代用材料表观断裂韧性Kc的尺寸效应。

关键词：高聚物粘结炸药(PBX) 表观断裂韧性断裂过程区尺寸效应修正最大切应力(MMTS)

新型仿竹六边形梯度层级多胞管耐撞性对比分析

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吉林大学学报（工学版） 2024年第2期54卷 333-345页

作者：邓小林杨馥模覃善甘梧州学院电子与信息工程学院广西梧州543002 广西大学机械工程学院南宁530004

设计并提出了一种新型的仿竹六边形梯度层级多胞管。首先,采用超折叠单元方法推导了六边形单梯度层级多胞管的平均冲击力的理论解,开展了方管的实验研究,利用理论解及实验结果对有限元数值模型的精确性进行了验证。其次,利用验证后的数... 详细信息

设计并提出了一种新型的仿竹六边形梯度层级多胞管。首先,采用超折叠单元方法推导了六边形单梯度层级多胞管的平均冲击力的理论解,开展了方管的实验研究,利用理论解及实验结果对有限元数值模型的精确性进行了验证。其次,利用验证后的数值模型分析了不同壁厚的仿竹六边形梯度层级多胞管的耐撞性能。最后,系统地研究了仿竹六边形梯度层级多胞管相比常规方管、六边形管、六边形单梯度层级多胞管在相同质量、相同初始峰值力和相同能量吸收条件下的耐撞性能。研究结果表明:提出的仿竹六边形梯度层级多胞管能有效降低结构的初始峰值力和提高结构的冲击力效率,在相同质量、相同初始峰值力和相同能量吸收条件下,仿竹六边形梯度层级多胞管的综合耐撞性能都要优于常规方管、六边形管和六边形单梯度层级多胞管。研究结果能为新型梯度层级多胞管的结构创新设计提供参考。

关键词：车辆工程耐撞性仿竹结构梯度层级多胞管能量吸收

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揭示氨对正己酸生产影响的机制——影响途径、关键酶和微生物

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Engineering 2024年第4期35卷 180-190页

作者： Qing-Lian Wu Ke-Xin Yuan Wei-Tong Ren Lin deng Hua-Zhe Wang Xiao-Chi Feng He-shan Zheng Nan-Qi Ren Wan-Qian Guo State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150090China College of Architecture and Environment Sichuan UniversityChengdu 610065China State Key Laboratory of Urban Water Resource and Environment School of Civil and Environmental EngineeringHarbin Institute of Technology(Shenzhen)Shenzhen 518055China College of Chemistry and Chemical Engineering Qiqihar UniversityQiqihar 161006China

n-Caproate,which is produced via chain elongation(CE)using waste biomass,can supply various fossilderived products,thus advancing the realization of carbon neutrality.Ammonia released from the degradation of nitrogen-rich waste biomass can act as a nutrient or an inhibitor in anaerobic bioprocesses,including CE,with the distinction being primarily dependent on its concentration.Currently,the optimal concentration of ammonia and the threshold of toxicity for open-culture n-caproate production using ethanol as an electron donor,along with the underlying mechanisms,remain unclear.This study revealed that the optimal concentration of ammonia for n-caproate production was 2.0 g∙L^(-1),whereas concentrations exceeding this threshold markedly suppressed the CE performance.Exploration of the mechanism revealed the involvement of two forms of ammonia(i.e.,ammonium ions and free ammonia)in this inhibitory behavior.High ammonia levels(5.0 g∙L^(-1))induced excessive ethanol oxidation and suppressed the reverse b-oxidation(RBO)process,directly leading to the enhanced activities of enzymes(phosphotransacetylase and acetate kinase)responsible for acetate formation and diminished activities of butyryl-coenzyme A(CoA):acetyl-CoA transferase,caproyl-CoA:butyryl-CoA transferase,and caproyl-CoA:acetyl-CoA transferase that are involved in the syntheses of n-butyrate and n-caproate.Furthermore,the composition of the microbial community shifted from Paraclostridium dominance(at 0.1 g∙L^(-1)ammonia)to a co-dominance of Fermentimonas,Clostridium sensu stricto 12,and Clostridium sensu stricto 15 at 2.0 g∙L^(-1)ammonia.However,these CE-functional bacteria were mostly absent in the presence of excessive ammonia(5.0 g∙L^(-1)ammonia).Metagenomic analysis revealed the upregulation of functions such as RBO,fatty acid synthesis,K^(+)efflux,adenosine triphosphatase(ATPase)metabolism,and metal cation export in the presence of 2.0 g∙L^(-1)ammonia,collectively contributing to enhanced n-caproate production.Conversely,the aforementioned functions(exc

关键词： Ammonia inhibition Medium chain fatty acids n-Caproate Enzyme Metagenomics

专利视角下航空航天领域稀土应用技术分布研究

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稀土 2024年第1期45卷 149-158页

作者：魏凤邓阿妹谷山强李涛中国科学院武汉文献情报中心湖北武汉430071 科技大数据湖北省重点实验室湖北武汉430071 南瑞集团公司江苏南京211106 国网电力科学研究院武汉南瑞有限责任公司湖北武汉430074

稀土元素在航空航天领域的应用是国内外关注重要领域。针对稀土在航空航天领域应用的技术创新状况,主要运用科学计量学和数学统计等方法,从申请国家和主要专利权人角度,开展稀土元素应用技术专利分析,发现航空领域稀土元素全球专利自申... 详细信息

稀土元素在航空航天领域的应用是国内外关注重要领域。针对稀土在航空航天领域应用的技术创新状况,主要运用科学计量学和数学统计等方法,从申请国家和主要专利权人角度,开展稀土元素应用技术专利分析,发现航空领域稀土元素全球专利自申请以来整体呈现增长趋势,尤其在2000年以后专利申请非常活跃,数量较大。稀土专利主要分布在合金、非金属产品及应用技术方面,2017—2019年尤其以陶瓷镀膜和飞机动力技术的专利申请较多,是这三年的热点领域。中美两国专利申请均超过其他国家,我国主要专利集中在钕、镧、铈、钇、钪等元素的应用上,美国则较多集中在钪、钇、铒、铈、钕、铽等元素的应用上,该领域全球主要专利权人是欧美公司。建议我国加强稀土在航空航天领域的系统研究布局,通过国际合作和自主创新等多种方式,提升我国稀土材料高端技术研发创新水平。

关键词：稀土元素航空航天专利科学计量法技术创新