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Application of geophysical methods in fine detection of urban concealed karst:A case study of Wuhan City,China

China Geology 2024年第3期7卷 517-532页

作者： dao-han Liu Lei Wang Lei Liu Jun-jie Xu Jian-qiang Wu pan Liu Wuhan Center China Geological SurveyWuhan430205China Central South China Center for Geoscience Innovation Wuhan430205China Geophysical Exploration Brigade of Hubei Geological Bureau Wuhan 430056China

The construction of modern livable cities faces challenges in karst areas,including ground collapse and engineering ***,with a population of 13.74×10^(6) and approximately 1161 km^(2.of soluble rocks in the urban area of 8569.15 km^(2.,predominantly consists of concealed karst areas where occasional ground collapse events occur,posing significant threats to underground engineering *** address these challenges,a comprehensive geological survey was conducted in Wuhan,focusing on major karstrelated *** methods offer advantages over drilling in detecting concealed karst areas due to their efficiency,non-destructiveness,and *** paper reviewed the karst geological characteristics in Wuhan and the geophysical exploration methods for karst,selected eight effective geophysical methods for field experimentation,evaluated their suitability,and proposed method combinations for different karst *** results show that different geophysical methods have varying applicability for karst detection in Wuhan,and combining multiple methods enhances detection *** specific recommendations for method combinations provided in this study serve as a valuable reference for karst detection in Wuhan.

关键词： Ground Penetrating Radar(GPR) Electric Resistivity Tomography(ERT) Opposing-coils Transient Electromagnetic Method(OCTEM) Microtremor Array Measurements(MAM) Multi-channel Analysis of surface wave(MASW) Multi-source surface wave exploration(MSSW) Electromagnetic wave CT(EM CT) Surface Nuclear Magnetic Resonance(SNMR) Concealed karst Urban geological survey engineering

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Recent progress and strategies of cathodes toward polysulfides shuttle restriction for lithium-sulfur batteries

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Rare Metals 2024年第9期43卷 4132-4161页

作者： Xing-You Rao Shuang-Fei Xiang Jian Zhou Zhen Zhang Xiang-Yu Xu Yuan-Yuan Xu Xin-Chi Zhou Zheng-dao pan Su-Chong Tan Shi-Xing Dong Zhou-Lu Wang Yu-Tong Wu Yun-Lei Zhou Xiang Liu Yi Zhang Shan Jiang School of Energy Sciences and Engineering Nanjing Tech UniversityNanjing 211816China School of Materials Science and Engineering and Institute of Smart Fiber Materials Zhejiang Sci-Tech UniversityHangzhou 310018China JiangSu Sailboat Petrochemical Co. LtdLianyungang 222000China Hangzhou Institute of Technology Xidian UniversityHangzhou 311200China

Lithium-sulfur batteries(LSBs)have already developed into one of the most promising new-generation high-energy density electrochemical energy storage systems with outstanding features including high-energy density,low cost,and environmental ***,the development and commercialization path of LSBs still presents significant limitations and challenges,particularly the notorious shuttle effect triggered by soluble longchain lithium polysulfides(LiPSs),which inevitably leads to low utilization of cathode active sulfur and high battery capacity degradation,short cycle life,*** research efforts have been conducted to develop various sulfur host materials capable of effectively restricting the shuttle *** review firstly introduces the fundamental electrochemical aspects of LSBs,followed by a comprehensive analysis of the mechanism underlying the shuttle effect in Li–S batteries and its profound influence on various battery components as well as the overall battery ***,recent advances and strategies are systematically reviewed,including physical confinement,chemisorption,and catalytic conversion of sulfur hosts for restricting LiPSs shuttle *** interplay mechanisms of sulfur hosts and LiPSs are discussed in detail and the structural advantages of different host materials are ***,key insights for the rational design of advanced host materials for LSBs are provided,and the upcoming challenges and the prospects for sulfur host materials in lithium-sulfur batteries are also explored.

关键词： Lithium-sulfur batteries Polysulfides Shuttle effect Host

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Identification of missing CYP450 enzymes involved in paclitaxel biosynthesis and heterologous reconstitution of baccatin III

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Chinese Journal of Natural Medicines 2024年第4期22卷 291-292页

作者： DU Jinfa LIAO pan LU Xu State Key Laboratory of Natural Medicines School of Traditional Chinese PharmacyChina Pharmaceutical UniversityNanjing 210009China Department of Biology Hong Kong Baptist UniversityKowloon TongHong KongChina State Key Laboratory of Agrobiotechnology The Chinese University of Hong KongHong KongChina State Key Laboratory for Quality Ensurance and Sustainable Use of dao-di Herbs Beijing 100700China Medical Botanical Garden China Pharmaceutical UniversityNanjing 210009China

Paclitaxel,a tetracyclic diterpenoid,has garnered attention for its potent anti-cancer properties and intricate molecular structure,making it a significant target for chemical synthesis and biosynthesis[1].However,its natural sources are extremely limited,as it is derived exclusively from the bark of endangered genus Taxus plants,which contain paclitaxel in very low concentrations(0.01%−0.05%)[2.3].Recent advances in synthetic biology present promising opportunities to enhance paclitaxel levels in Taxus cell cultures or to enable the reconstitution of its production in heterologous hosts,such as yeast or tobacco(Nicotiana benthamiana).

关键词： Paclitaxel biosynthesis Baccatin III Cytochrome P450 Taxane oxetanase 1 Heterologous reconstitution

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基于改进YOLOv7的火电厂管道及阀门泄漏分割与检测

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控制与决策 2024年第9期39卷 2977-2986页

作者：彭道刚陈晨王丹豪潘俊臻上海电力大学自动化工程学院上海200090 上海电力大学电气工程学院上海200090

火电厂关键区域的管道、阀门等设备时常发生油液、蒸汽等物质的泄漏故障.为了提高火电厂管道及阀门泄漏故障的分割与检测精度,加快模型推理速度,提出一种基于改进YOLOv7的火电厂管道及阀门泄漏分割与检测算法,通过在YOLOv7网络中加入相... 详细信息

火电厂关键区域的管道、阀门等设备时常发生油液、蒸汽等物质的泄漏故障.为了提高火电厂管道及阀门泄漏故障的分割与检测精度,加快模型推理速度,提出一种基于改进YOLOv7的火电厂管道及阀门泄漏分割与检测算法,通过在YOLOv7网络中加入相关实例分割模块,实现实例分割与目标检测任务的并行;通过融入极化自注意力机制和可分离的视觉深度自注意力模块(separable vision transformer),弱化复杂背景的干扰,强化对泄漏区域的边缘提取;在后处理阶段运用置信度传播簇机制(confidence propagation cluster, CP-cluster),提高模型定位的准确性;在颈部网络使用幽灵卷积降低特征冗余,并通过通道剪枝技术压缩模型,实现模型轻量化.实验结果表明,在加入各项改进后,算法分割任务与检测任务的mAP@0.5:0.95指标分别达到75.7%、82.2.,相较于基础模型,指标分别提高了11.9%、7.1%,且模型参数量减少了30.3%,可有效地应用于电厂的实际生产环境中.

关键词：泄漏检测实例分割目标检测自注意力机制置信度传播簇机制通道剪枝

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柑橘园土壤与叶片养分对“红美人”果实品质的影响

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中国土壤与肥料 2024年第7期 192-199页

作者：焦云沈盼谢让金韩东道宁波市农业科学研究院林业研究所浙江宁波315040 宁波市特色园艺作物品质调控与抗性育种重点实验室浙江宁波315040 西南大学/中国农业科学院柑桔研究所重庆400712 宁波市田园牧歌农业发展有限公司浙江宁波315727

为探明土壤及叶片养分对“红美人”果实品质的影响效应,对浙江省宁波市象山县33个“红美人”果园土壤、叶片养分和果实品质进行测定及评价,通过多元统计分析筛选影响其果实品质的主要土壤及叶片养分因子,明确果实品质、土壤及叶片养分... 详细信息

为探明土壤及叶片养分对“红美人”果实品质的影响效应,对浙江省宁波市象山县33个“红美人”果园土壤、叶片养分和果实品质进行测定及评价,通过多元统计分析筛选影响其果实品质的主要土壤及叶片养分因子,明确果实品质、土壤及叶片养分之间的相关性。研究结果表明,调查果园中土壤pH处于偏酸性环境,平均值为5.41,土壤养分总体偏高。其中,有效铁、有效锰、有效铜、有效锌、有效磷、速效钾、交换性钙、交换性镁、全氮、全磷和全钾含量平均值超出适宜范围;同时,叶片中铁、锰和氮含量均值亦高于适宜范围,而钾和钙含量则低于适宜范围。果实品质是多个土壤及叶片养分因子综合作用的结果,果实可溶性固形物含量与土壤中有效锰和碱解氮含量呈正相关性,相关系数分别为0.55和0.45;果肉紧实度与土壤中有效锌、有效磷、全磷和碱解氮含量呈负相关性,相关系数分别为-0.83、-0.79、-0.50和-0.51;果肉酸度与叶片中钾和磷含量亦存在相关性,相关系数分别为-0.63和-0.50。逐步回归分析获得了影响“红美人”叶片中氮、磷、镁、锰、铜和锌含量的主要土壤养分因子。因此,针对上述果园土壤进行酸碱度调节,增施生理碱性有机肥等将作为后续土壤管理的关键。

关键词：红美人土壤养分叶片养分果实品质多元统计分析

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光果柱花草转基因毛状根及其原生质体制备体系的建立

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草地学报 2024年第5期32卷 1583-1591页

作者：孙昊张建禹罗丽娟刘攀道海南大学热带农林学院海南海口570228 海南大学三亚南繁研究院海南三亚572025 中国热带农业科学院热带作物品种资源研究所农业农村部华南作物基因资源与种质创制重点实验室&海南省热带作物资源遗传改良与创新重点实验室海南海口571101

光果柱花草(Stylosanthes leiocarpa)是柱花草属(Stylosanthes Sw.)中可用于林果园间作的一个野生种。截至目前,光果柱花草的转基因体系尚未建立。本研究以光果柱花草的子叶节为外植体,比较不同的发根农杆菌菌株与潮霉素B浓度对毛状根... 详细信息

光果柱花草(Stylosanthes leiocarpa)是柱花草属(Stylosanthes Sw.)中可用于林果园间作的一个野生种。截至目前,光果柱花草的转基因体系尚未建立。本研究以光果柱花草的子叶节为外植体,比较不同的发根农杆菌菌株与潮霉素B浓度对毛状根诱导率及转基因阳性率的影响。结果发现,以K599为诱导菌株且培养基添加8 mg·L^(-1)潮霉素B为筛选压,是最优的毛状根诱导条件,诱导率达2..33%,阳性率为100%。在此基础上,利用转基因毛状根制备原生质体,结果表明,添加2.5%纤维素酶和2.离析酶,以及8 h的酶解时间为最优条件,原生质体的产量达2.745×10^(5)个·g^(-1),活力为91.02.,制备的原生质体100%为转基因细胞。本研究成功建立了一种发根农杆菌介导的光果柱花草转基因毛状根诱导体系及原生质体制备体系,为后续光果柱花草的基因功能研究奠定了基础。

关键词：光果柱花草发根农杆菌转基因毛状根原生质体制备

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面向制造与装配的设计的装配式竖向预制混凝土构件参数化设计与应用

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科学技术与工程 2024年第13期24卷 5480-5490页

作者：邹贻权余有董道德潘寒湖北工业大学土木建筑与环境学院武汉430068 长沙理工大学土木工程学院长沙410114 中建三局科创产业发展有限公司武汉430095

装配式建筑设计、生产过程存在标准化程度低、数据联系较差等诸多问题。引入了制造业中面向制造与装配的设计(design for manufacturing and assembly,DFMA)的产品设计理念,研究了装配式建筑竖向预制混凝土(precast concrete,PC)构件的... 详细信息

装配式建筑设计、生产过程存在标准化程度低、数据联系较差等诸多问题。引入了制造业中面向制造与装配的设计(design for manufacturing and assembly,DFMA)的产品设计理念,研究了装配式建筑竖向预制混凝土(precast concrete,PC)构件的快速建模与深化设计应用,通过对建筑企业大量装配式建筑项目PC构件深化设计图纸的梳理分析,分析了图纸中构件组成规律,创新性地将PC构件二次拆分为模块。分析模块的种类、组合规律、数据架构等,形成模块的设计标准。将设计标准融入建筑信息模型(building information modeling,BIM)软件中,并开发相应的工具软件实现模块的快速建模。以软件创建的参数化标准模块为基础,以关联、匹配、调取、组合、拆解的关键技术实现PC构件的深化设计与工厂的制造联系。最后,通过实际工程案例进行测试对比。结果表明,竖向PC构件的建模速度提升70%、深化设计效率提升约80%,深化设计费用节省约80%,实现最小制造成本。研究结果有助于构建装配式建筑标准化的设计和生产体系,推广少规格多组合的设计方法,强化数据联系,提高装配式建筑的综合效益。

关键词： PC构件 BIM DFMA 模块化标准化参数化设计

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Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.L.Zhu S.M.Weng P.Li X.F.Li H.Ai H.R.pan Z.M.Sheng Key Laboratory for Laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(THz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or THz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or THz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and THz spectral ranges.

关键词： laser ultrashort photon

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新能源汽车电池包箱体结构优化及底部碰撞研究

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价值工程 2024年第10期43卷 101-105页

作者：孙昕辰张凯李祥潘道远安徽工程大学机械与汽车工程学院芜湖241000 亚新科噪声与振动技术(安徽)有限公司宁国242300

电池包箱体作为电池包的承载部件,它的结构设计对于提高电池包安全性能具有重要意义。以某款新能源汽车电池包为研究对象,建立电池包箱体有限元模型进行分析。电池包箱体结构变形量较大,前二阶固有频率相对较低,需要对电池包箱体结构进... 详细信息

电池包箱体作为电池包的承载部件,它的结构设计对于提高电池包安全性能具有重要意义。以某款新能源汽车电池包为研究对象,建立电池包箱体有限元模型进行分析。电池包箱体结构变形量较大,前二阶固有频率相对较低,需要对电池包箱体结构进行优化设计。以提高一阶固有频率为优化目标,建立电池包箱体结构优化模型。电池包箱体经过结构优化设计后,前二阶固有频率分别提高到2..2.Hz和34.3Hz,能够合理避开路面激励频率。利用Ansys软件对电池包下箱体进行碰撞分析。碰撞体的最大侵入量为0.818mm,远小于4.5mm,满足新能源汽车碰撞的安全要求。

关键词：新能源汽车电池包结构优化模态分析底部碰撞

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Protective effect of selenium-enriched lactobacilluson CCI_4-induced liver injury in mice and its possible mechanisms

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World Journal of Gastroenterology 2005年第37期11卷 5795-5800页

作者： Long Chen dao-Dong pan Juan Zhou Ying-Zi Jiang College of Life Sciences Nanjing Normal University Jiangsu Engineering Research Center for Bio-Medical Function Materials Nanjing 210097 Jiangsu Province China Department of Food Sciences Nanjing Normal University Nanjing 110097 Jiangsu Province China

AIM： To study the protective effects and mechanisms of Se-enriched lactobacillus on liver injury caused by carbon tetrachloride （CCl4） in mice. METHODS： Seventy-two ICR mice were randomly divided into four groups： normal group, CCl4-induced model group, low Se-enriched lactobacillus treatment group （L-Se group）, and high Se-enriched lactobacillus treatment group （H-Se group）. During a 3-wk experimental period, the common complete diet was orally provided daily for normal group and model group, and the mice in L-Se and H-Se groups were given a diet with 2.and 4 mg of organoselenium from Se-enriched lactobacillus per kg feed, respectively. From the 2.d wk of experiment, the model group, L-Se group, and H-Se group received abdominal cavity injection of olive oil solution containing 500 mL/L CCl4 （0.07 mL/100 g body mass） to induce liver injury, and the normal group was given olive oil on every other day for over 2.wk. In the first 2.wk post injection with CCl4, mice in each group were killed. The specimens of blood, liver tissue, and macrophages in abdominal cavity fluid were taken. Then the activities of the following liver tissue injury-associated enzymes including glutathione peroxidase （GSH-Px）, superoxide dismutase （SOD）, alanine aminotransferase （ALT） and aspartate aminotransferase （AST） as well as malondialdehyde （MDA） content were assayed. Changes of phagocytic rate and phagocytic index in macrophages were observed with Wright-Giemsa stain. Plasma TNF-α level was measured by radioimmunoassay. The level of intracellular free Ca^2. （[Ca^2.]i） in hepatocytes was detected under a laser scanning confocal microscope. RESULTS： During the entire experimental period, the AST and ALT activities in liver were greatly enhanced by CCl4 and completely blunted by both low and high doses of Se-enriched lactobacillus. The Se-enriched lactobacillus- protected liver homogenate GSH-Px and SOD activities were higher or significantly higher than those in model group and were close t

关键词： Se-enriched lactobacillus Liver injury Carbon tetrachloride Macrophage Ca^2.

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