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Large eddy simulation of boundary layer combustion of hydrogen and hydrocarbon fuel films in a modeled scramjet combustor

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Chinese Journal of Aeronautics 2024年第7期37卷 109-133页

作者： Jianfei WEI Silong ZHANG Jingying ZUO Xin LI Jiang QIN wen bao School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Supersonic fuel film cooling is a promising way to simultaneously reduce the severe wall heat and friction load of the internal passage in a scramjet engine when operating at hypersonic *** eddy simulations were performed to investigate the cooling and wall friction characteristics of hydrogen and hydrocarbon films under inert and reactive *** results show that the essential difference of the turbulent state in the mixing layer contributes to the totally different behaviors of the cooling and wall friction reduction performances of the two fuel *** turbulent transport processes between the hydrogen film and the mainstream are much weaker as compared to the case of hydrocarbon film,making inert hydrogen rather superior in cooling and friction reduction ***,the increase of wall temperature for hydrogen film under the inert case is mainly driven by the loss of hydrogen with high heat capacity instead of by direct heat ***,the film cooling performance severely deteriorates when the hydrogen film burns due to presence of severe heat release sources near the *** the other hand,combustion of hydrocarbon film in the boundary layer can remarkably improve its originally barely-satisfactory cooling and friction reduction performance to the level comparable to that of hydrogen film,due to the suppression of turbulent transport processes in the mixing layer and presence of heat absorption sources near the ***,the hydrogen film is more advantageous in friction reduction,while the hydrocarbon film is more suitable for cooling.

关键词： Supersonic film cooling Hydrogen Hydrocarbon Boundary layer combustion Large eddy simulation

Impacts of Future Changes in Heavy Precipitation and Extreme Drought on the Economy over South China and Indochina

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Advances in Atmospheric Sciences 2024年第6期41卷 1184-1200,I0022-I0034页

作者： Bin TANG wenting HU Anmin DUAN Yimin LIU wen bao Yue XIN Xianyi YANG State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 101408China State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China Chinese Academy of Sciences the CAS Institutes of Science and DevelopmentBeijing 101408China School of Public Policy and Management University of Chinese Academy of SciencesBeijing 101408China

Heavy precipitation and extreme drought have caused severe economic losses over South China and Indochina(INCSC)in recent *** the areas with large gross domestic product(GDP)in the INCSC region are distributed along the coastline and greatly affected by global warming,understanding the possible economic impacts induced by future changes in the maximum consecutive 5-day precipitation(RX5day)and the maximum consecutive dry days(CDD)is critical for adaptation planning in this *** on the latest data released by phase 6 of the Coupled Model Intercomparison Project(CMIP6),future projections of precipitation extremes with bias correction and their impacts on GDP over the INCSC region under the fossil-fueled development Shared Socioeconomic Pathway(SSP5-8.5)are *** indicate that RX5day will intensify robustly throughout the INCSC region,while CDD will lengthen in most regions under global *** changes in climate consistently dominate the effect on GDP over the INCSC region,rather than the change of *** only considering the effect of climate change on GDP,the changes in precipitation extremes bring a larger impact on the economy in the future to the provinces of Hunan,Jiangxi,Fujian,Guangdong,and Hainan in South China,as well as the Malay Peninsula and southern Cambodia in ***,timely regional adaptation strategies are urgent for these ***,from the sub-regional average viewpoint,over two thirds of CMIP6 models agree that maintaining a lower global warming level will reduce the economic impacts from heavy precipitation over the INCSC region.

关键词： CMIP6 heavy precipitation extreme drought South China Indochina economic impact

Design and performance evaluation of a large field-of-view dual-particle time-encoded imager based on a depth-of-interaction detector

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Nuclear Science and Techniques 2024年第4期35卷 1-14页

作者： Dong Zhao Xu-wen Liang Ping-Kun Cai Wei Cheng wen-bao Jia Da-Qian Hei Qing Shan Yong-Sheng Ling Chao Shi Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions Suzhou 215000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

Time-encoded imaging is useful for identifying potential special nuclear materials and other radioactive sources at a *** this study,a large field-of-view time-encoded imager was developed for gamma-ray and neutron source hotspot imaging based on a depth-of-interaction(DOI)*** imager primarily consists of a DOI detector system and a rotary dual-layer cylindrical coded *** EJ276 plastic scintillator coupled with two SiPMs was designed as the DOI detector to increase the field of view and improve the imager *** difference in signal time at both ends and the log of the signal amplitude ratio were used to calculate the interaction position *** position resolution of the DOI detector was calibrated using a collimated Cs-137 source,and the full width at half maximum of the reconstruction position of the Gaussian fitting curve was approximately 4.4 *** DOI detector can be arbitrarily divided into several units to independently reconstruct the source distribution *** unit length was optimized via Am-Be source-location experiments.A multidetector filtering method is proposed for image *** method can effectively reduce image noise caused by poor DOI detector position *** vertical field of view of the imager was(-55°,55°)when the detector was placed in the center of the coded mask.A DT neutron source at 20 m standoff could be located within 2400 s with an angular resolution of 3.5°.

关键词： Time-encoded imager Depth-of-interaction detector Dual-particle imaging Hotspot imaging

Atroposelective Synthesis of 2-Arylindoles via Chiral Phosphoric Acid-Catalyzed Direct Amination of Indoles

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Chinese Journal of Chemistry 2024年第7期42卷 731-735页

作者： wen bao Ye-Hui Chen Yu-Wei Liu Shao-Hua Xiang Bin Tan School of Pharmacy&StateKey Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu 730000China Shenzhen Grubbs Institute Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong 518055China

Indole-based atropisomers are a very important class of axially chiral ***,the atroposelective synthesis of axially chiral 2-arylindole remains largely *** this study,we report the successful synthesis of atropisomeric 2-arylindoles using direct amination of indoles with p-quinonediimines in the presence of chiral phosphoric acid as a *** acts as an aminating reagent through formal polarity inversion of *** malonate group on the 2-aryl of 2-indoles was found to be essen-tial for high enantioselectivity of the *** could be due to the additional interaction between the ester group and the cata-lyst,as well as the intramolecular hydrogen *** findings provide a new strategy for the asymmetric construction of 2-arylindole atropisomers.

关键词： Chiral phosphoric acid Quinonediimines Direct amination Nucleophilic addition Asymmetric catalysis Enantioselectivity Axially chiral 2-arylindole Atroposelective synthesis

Multi-omics analyses provide insights into the evolutionary history and the synthesis of medicinal components of the Chinese wingnut

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Plant Diversity 2024年第3期46卷 309-320页

作者： Zi-Yan Zhang He-Xiao Xia Meng-Jie Yuan Feng Gao wen-Hua bao Lan Jin Min Li Yong Li College of Life Science and Technology Inner Mongolia Normal UniversityHohhot 010020China Key Laboratory of Biodiversity Conservation and Sustainable Utilization in Mongolian Plateau for College and University of Inner Mongolia Autonomous Region Hohhot 010022China College of Landscape and Art Henan Agricultural UniversityZhengzhou 450002China State Key Laboratory of Tree Genetics and Breeding Chinese Academy of ForestryBeijing 100091China

Chinese wingnut(Pterocarya stenoptera)is a medicinally and economically important tree species within the family ***,the lack of high-quality reference genome has hindered its in-depth *** this study,we successfully assembled its chromosome-level genome and performed multiomics analyses to address its evolutionary history and synthesis of medicinal components.A thorough examination of genomes has uncovered a significant expansion in the Lateral Organ Boundaries Domain gene family among the winged group in *** notable increase may be attributed to their frequent exposure to flood-prone *** further differentiation between Chinese wingnut and Cyclocarya paliurus,significant positive selection occurred on the genes of NADH dehydrogenase related to mitochondrial aerobic respiration in Chinese wingnut,enhancing its ability to cope with waterlogging *** genomic analysis revealed Chinese wingnut evolved more unique genes related to arginine synthesis,potentially endowing it with a higher capacity to purify nutrient-rich water *** of terpene synthase families enables the production of increased quantities of terpenoid volatiles,potentially serving as an evolved defense mechanism against herbivorous *** combined transcriptomic and metabolomic analysis,we identified the candidate genes involved in the synthesis of terpenoid *** study offers essential genetic resources for Chinese wingnut,unveiling its evolutionary history and identifying key genes linked to the production of terpenoid volatiles.

关键词： Genome Medicinal components Metabolome Pterocarya stenoptera Transcriptome

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区域学校评价结果运用困境及其破解研究

教学与管理 2024年第13期 72-76页

作者：鲍雯雯杭州市西湖区教育督导评估中心杭州310000

学校评价在推动区域和学校发展进程中扮演着至关重要的角色。它不仅深入挖掘并整合了教学质量、学生发展和管理效能的综合性数据与反馈,还为教育政策的精准制定与动态调整、资源的科学分配、教育质量的全面提升以及教育公平的稳步推进... 详细信息

学校评价在推动区域和学校发展进程中扮演着至关重要的角色。它不仅深入挖掘并整合了教学质量、学生发展和管理效能的综合性数据与反馈,还为教育政策的精准制定与动态调整、资源的科学分配、教育质量的全面提升以及教育公平的稳步推进奠定了坚实的基础。然而,在实际运用评价结果的过程中,许多区域与学校仍面临很多现实问题,尤其是教师对数据的解读能力及学校获取区域支持与引导等方面存在明显缺失。可以通过开发支持性工具如反馈报告、微课和学校改进计划模板等解决这些问题,并有效推动评价结果的运用。杭州市西湖区通过提供这些支持性工具,构建学校改进的多层次反馈机制、搭建资源支持平台以及设计提升教师数据素养的系统培训课程等,实践并形成了多维度保障机制,提升了学校评价结果的实际效用,助推区域内各学校更优发展。

关键词：学校管理学校评价评价结果学习支架理论问题支架支持性工具数据素养

中枢神经系统感染病原体宏基因组测序试剂性能评估关注点

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中国医疗器械杂志 2024年第3期48卷 343-345页

作者：包雯刘容枝国家药品监督管理局医疗器械技术审评中心北京市100081

从性能评估的角度,简述中枢神经系统感染病原体宏基因组测序试剂检测的病原体范围、企业参考品的设置、反应体系的研究以及分析性能评估等研究内容的关注点,包括研究方法以及质量控制要求等。该研究意在提高产品研发效率,推动行业发展。

关键词：中枢神经系统感染病原体宏基因组测序试剂分析性能评估

国外药品前沿技术监管实践及启示--以美国药品监督管理实践为例

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中国新药杂志 2024年第3期33卷 229-240页

作者：余明丽夏文静姜晓萌温宝书国家药品监督管理局药品审评中心北京100076

美国FDA对于药品前沿技术的发展进行快速响应,致力于促进创新产品的快速上市,最大限度的满足公众健康需求。本文拟通过对美国FDA药品前沿技术监管领域的相关政策、行动计划、技术指南以及实施程序等进行分析总结,以期为我国前沿技术领... 详细信息

美国FDA对于药品前沿技术的发展进行快速响应,致力于促进创新产品的快速上市,最大限度的满足公众健康需求。本文拟通过对美国FDA药品前沿技术监管领域的相关政策、行动计划、技术指南以及实施程序等进行分析总结,以期为我国前沿技术领域医药产品的科学监管提供借鉴。

关键词：药品前沿技术监管

沟眶象味觉受体基因EscrGR8对雌成虫繁殖力的影响

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昆虫学报 2024年第3期67卷 307-317页

作者：郭晓丽文超温俊宝温晓健北京林业大学林木资源高效生产全国重点实验室北京100083 北京林业大学林木有害生物防治北京市重点实验室北京100083 北京林业大学草业与草原学院北京100083 中国林业科学研究院森林生态环境与自然保护研究所国家林业和草原局森林保护学重点实验室北京100091

【目的】分析和阐明沟眶象Eucryptorrhynchus scrobiculatus味觉受体基因EscrGR8的分子特性和功能,揭示其调节雌成虫繁殖力的作用。【方法】基于沟眶象触角转录组数据库,采用RACE克隆EscrGR8的cDNA全长序列;利用qRT-PCR检测EscrGR8在沟... 详细信息

【目的】分析和阐明沟眶象Eucryptorrhynchus scrobiculatus味觉受体基因EscrGR8的分子特性和功能,揭示其调节雌成虫繁殖力的作用。【方法】基于沟眶象触角转录组数据库,采用RACE克隆EscrGR8的cDNA全长序列;利用qRT-PCR检测EscrGR8在沟眶象不同发育阶段(卵、1-6龄幼虫、蛹、雌成虫和雄成虫)和雌雄成虫组织(去除触角和喙的头、触角、口器、中肠、前足、睾丸、卵巢、雄虫交配器和雌虫产卵器)中的表达量。显微注射雌成虫dsRNA后0,6,12,24,36,48和72 h时利用qRT-PCR检测RNAi后EscrGR8的表达量。检测显微注射dsEscrGR8后1-5 d和6-11 d时沟眶象雌成虫在不同土壤含水量(0~10%,11%~20%,21%~40%,41%~60%,61%~80%和81%~100%)条件下的产卵选择率、总产卵数量和所产卵的孵化率,研究抑制EscrGR8表达对雌成虫产卵选择性和繁殖力的影响。【结果】成功克隆了沟眶象EscrGR8(GenBank登录号:OR836580)的cDNA全长序列,开放阅读框(ORF)长1251 bp,编码了416个氨基酸,具有6个跨膜结构域。多序列比对和系统发育进化分析结果表明,EscrGR8与其他昆虫的GR的氨基酸序列同源性普遍较低,其中与棉铃象甲Anthonomus grandis的AgraGR64f氨基酸序列一致性为30.96%。qRT-PCR检测结果表明,EscrGR8在沟眶象不同发育阶段和成虫组织中的表达量具有显著差异,EscrGR8在雌成虫中的表达量最高,在卵中的表达量最低;EscrGR8在雌成虫卵巢中特异性高表达。显微注射dsEscrGR8不仅在一定时间内显著降低EscrGR8的表达量,并且对雌成虫的产卵选择性具有显著影响。显微注射dsEscrGR8后1-5 d时沟眶象雌成虫在含水量21%~40%土壤条件下的产卵选择率和所产卵的孵化率与显微注射dsGFP的对照组相比分别显著降低了24.66%和15.83%;在含水量81%~100%土壤条件下的产卵选择率与显微注射dsGFP的对照组相比显著增加了28.39%,雌成虫所产卵几乎不孵化。【结论】本研究证实了味觉受体基因EscrGR8对沟眶象雌成虫产卵选择和繁殖力的影响,有助于理解昆虫味觉受体基因的多样性和功能特异性。

关键词：沟眶象产卵量味觉受体基因 RNAi 表达模式