检索结果-南通市图书馆

DEM investigation of strength and critical state behaviours of granular materials under true triaxial loadings

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第2期85卷 198-212页

作者： Minyi Zhu Guobin gong Jun Xia Stephen Wilkinson Department of Civil Engineering Xi'an Jiaotong-Liverpool UniversityChina Department of Civil Engineering and Industrial Design University of LiverpoolLiverpoolUK Faculty of Engineering and Information Sciences University of Wollongong in DubaiUnited Arab Emirates

This paper investigates the strength and critical state(CS)behaviours of granular materials via DEM simulations of true triaxial drained tests under three different loading modes including constant b(in-termediate stress ratio)tests with constantσ'1(major principal stress),constant p(mean pressure)and constantσ'3(minor principal stress)*** this end,a series of samples are generated with the same particle size distribution,and with the confining stresses ranging from 100 kPa to 900 *** CS is achieved for all *** the macroscopic behaviours and the microscopic behaviours are examined and compared considering different loading modes,confining stresses and intermediate stress ratios(b).The critical state lines(CSLs)are found to be unique and independent of the loading modes,but dependent on the b *** CSLs with b=0 and b=1 form the two boundaries of CSLs respectively beyond which CSLs under all other b tests cannot go *** different strength criteria are examined and compared in terms of both peak and CS *** Mohr-Coulomb strength criterion is found to be only suitable for axisymmetric loading *** Lade-Duncan criterion is only suitable for describing peak strengths,which is dependent on the loading modes and confining *** Satake criterion and Matsuoka-Nakai criterion are the more appropriate strength criteria for describing CS failures,indicating that the CS values of both the Satake parameter and the Matsuoka-Nakai parameter describe an inherent property that characterizes the CS failure for a given type of *** CS mechanical coordination number is fitted by a curved line for a given b value,which is unique regardless of the loading *** peak and CS values of both major and minor principal fabric tensors decrease with increasing b values,while they increase with increasing b values for the intermediate principal fabric tensor.

关键词： Discrete element method Intermediate stress ratio Dilation Critical state Failure criterion

International law obligations for the disposal of Fukushima nuclear-contaminated water under the principles of nuclear safety

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Population,Resources and Environment 2024年第1期22卷 10-19页

作者： Wei gong Law School Southwest UniversityChongqing 400715China

The disposal of contaminated water from Japan’s Fukushima nuclear power plant is a significant international nuclear safety issue with considerable cross-border *** matter requires compliance not only with the law of the sea but also with the principles of nuclear safety under international *** principles serve as the overarching tenet of international and China’s domestic nuclear laws,applicable to nuclear facilities and *** principle of safety in nuclear activities is fully recognized in international and domestic laws,carrying broad legal binding ***’s discharge of nuclear-contaminated water into the sea violates its obligations under the principle of safety in nuclear activities,including commitments to optimum protection,as low as reasonably practicable,and *** Japanese government and the International Atomic Energy Agency(IAEA)have breached the obligation of optimum protection by restricting the scope of assessments,substituting core concepts,and shielding dissenting *** the absence of clear radiation standards,they have acted unilaterally without fulfilling the obligation as low as reasonably practicable *** discharge of Fukushima nuclear-contaminated water poses an imminent and unpredictable risk to all countries worldwide,including Japanese *** and the IAEA should fulfill their obligations under international law regarding disposal,adhering to the principles of nuclear safety,including optimum protection,the obligation as low as reasonably practicable,and prevention through multilateral ***,the obligation to provide optimum protection should be implemented by re-evaluating the most reliable disposal technologies and methods currently available and comprehensively assessing various *** standard of the obligation as low as reasonably practicable requires that the minimization of negative impacts on human health,livelihoods,and the environment should not b

关键词： Principles of nuclear safety Disposal of nuclear-contaminated water Optimum protection Prevention As low as reasonably achievable

Acupuncture Legislation in the United States: Minnesota as a Case Study

在线全文

学校读者我要写书评

暂无评论

Chinese Medicine and Culture 2024年第2期7卷 104-118页

作者： Changzhen gong American Academy of Traditional Chinese Medicine Roseville 55113USA

2023 marks the 50th anniversary of legal regulation of acupuncture in the United States,as the first acupuncture law was enacted in ***,like any other medical modality,is regulated at the state level,with each state formulating and enforcing its own laws and statutes over *** article narrates the legislative process and major developments of the acupuncture profession in Minnesota,in the context of legislative developments across the *** tells how this midsize,Midwest state’s acupuncture profession became regulated,and examines the challenges faced by the profession before and after state statutes were *** stands as a representative example of the legislative process in other states.

关键词： Acupuncture Acupuncture law Legislature Minnesota Acupuncture Association Minnesota Board of Medical Practice Minnesota Department of Health

Metagenomics reveals the microbial community and functional metabolism variation in the partial nitritation-anammox process:From collapse to recovery

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第1期135卷 210-221页

作者： Hong Wang Hui gong Xiaohu Dai Min Yang State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China BIOMATH Department of Data Analysis and Mathematical ModellingGhent UniversityGhent 9000Belgium

Mainstream partial nitritation-anammox(PNA)process easily suffers from performance instability and even reactor collapse in ***,it is of great significance to unveil the characteristic of performance recovery,understand the intrinsic mechanism and then propose operational *** this study,we combined long-term reactor operation,batch tests,and metagenomics to reveal the succession of microbial community and functional metabolism variation from system collapse to *** aeration control(0.10-0.25mg O_(2)/L)was critical for performance *** was also found that Candidatus Brocadia became the dominant flora and its abundance increased from 3.5%to 11.0%.Significant enhancements in carbon metabolism and phospholipid biosynthesis were observed during system recovery,and the genes abundance related to signal transduction was dramatically *** up-regulation of sdh and suc genes showed the processes of succinate dehydrogenation and succinyl-CoA synthesis might stimulate the production of amino acids and the synthesis of proteins,thereby possibly improving the activity and abundance of AnAOB,which was conducive to the performance ***,the increase in abundance of hzs and hdh genes suggested the enhancement of the anammox *** in the abundance of key genes involved in nitrogen metabolism indicated that nitrogen removal pathway was more diverse after system *** achievement of performance recovery was driven by anammox,nitrification and denitrification coupled with dissimilatory nitrate reduction to *** results provide deeper insights into the recovery mechanism of PNA system and also provide a potential regulation strategy for the stable operation of the mainstream PNA process.

关键词： Partial nitritation-anammox Metagenomics Microbial community Functional metabolism Recovery

在线全文

学校读者我要写书评

暂无评论

城乡教育结对共建须在“建”上做文章

中小学校长 2022年第7期 11-13页

作者：龚俊波湖北省宜昌市秭归县归州镇初级中学

为进一步扩大城乡交流,缩小城乡教育差距,促进乡村薄弱学校与城区优质教育学校教育结对共建,由湖北省宜昌市教育局牵头,部分区、县教育局共同发力,通过教师双向交流、管理人员跟岗培训、学校互访互学等形式,以学校管理、课程实施、课堂... 详细信息

为进一步扩大城乡交流,缩小城乡教育差距,促进乡村薄弱学校与城区优质教育学校教育结对共建,由湖北省宜昌市教育局牵头,部分区、县教育局共同发力,通过教师双向交流、管理人员跟岗培训、学校互访互学等形式,以学校管理、课程实施、课堂教学改革、校本研修、校园文化等方面为突破口,帮助湖北省宜昌市秭归县归州镇初级中学构建发展愿景、完善管理机制、搭建工作平台,让学校向阳而生,进而推动乡村教育振兴。

关键词：乡村振兴城乡教育结对共建

在线全文

学校读者我要写书评

暂无评论

人体生物矿化与病态结晶研究进展

科学通报 2023年第4期68卷 339-355页

作者：朱佐轩李斯汤伟伟龚俊波王静康天津大学化工学院化学工程联合国家重点实验室天津300072

生物体通过矿化结晶可制备出具有多层级结构有序的功能材料以实现特定生物功能,但是有害(或病态)的结晶过程则会诱发诸如肾结石、动脉粥样硬化、疟疾、痛风等疾病.迄今为止,科学家对哺乳动物体内无机或有机盐病态矿化结晶的分子机制认... 详细信息

生物体通过矿化结晶可制备出具有多层级结构有序的功能材料以实现特定生物功能,但是有害(或病态)的结晶过程则会诱发诸如肾结石、动脉粥样硬化、疟疾、痛风等疾病.迄今为止,科学家对哺乳动物体内无机或有机盐病态矿化结晶的分子机制认识仍不清楚,但随着结晶科学推动病态矿化领域的发展,生物病态结晶研究近年来已取得了众多突破性成果和重要进展.本文从结晶过程机理认识和抑制药物分子开发需求出发,首先介绍了病态矿化结晶过程诱发的几种常见人类疾病,综述了这些疾病相关的无机或有机盐晶体结晶过程机制的研究进展,重点阐述了诱发肾结石形成的晶体成核、生长、聚结和黏附不同阶段、不同尺度的分子机制研究进展以及结晶抑制药物分子的设计开发策略.最后,梳理了今后生物病态结晶领域研究的重点方向,为病态矿化引发的人类疾病的预防、治疗和药物研究开发提供指导.

关键词：生物矿化病理性(病态)结晶成核晶体生长分子设计抑制剂

Eco-evolutionary evidence for the global diversity pattern of Cycas(Cycadaceae)

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2024年第6期66卷 1170-1191页

作者： Jian Liu Anders JLindstrom Yiqing gong Shanshan Dong Yusheng(Chris)Liu Shouzhou Zhang Xun gong CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Department of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant ResourcesKunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Global Biodiversity Conservancy 144/124 Moo3Soi Bua ThongBangsalaeSattahipChonburi 20250Thailand Key Laboratory of Southern Subtropical Plant Diversity Fairy Lake Botanical GardenShenzhen&Chinese Academy of SciencesShenzhen 518004China Department of Earth and Environmental Sciences Indiana University-IndianapolisIndianapolisIN 46202USA

The evolution of the latitudinal diversity gradient(LDG),characterized by a peak in diversity toward the tropics,has captured significant attention in evolutionary biology and ***,the inverse LDG(i-LDG)mechanism,wherein species richness increases toward the poles,remains inadequately *** are among one of the oldest lineages of extant seed plants and have undergone extensive diversification in the ***,the extant cycad abundance exhibits an i-LDG pattern,and the underlying causes for this phenomenon remain largely ***,using 1,843 nuclear genes from a nearly complete sampling,we conducted comprehensive phylogenomic analyses to establish a robust species-level phylogeny for Cycas,the largest genus within *** then reconstructed the spatial-temporal dynamics and integrated global environmental data to evaluate the roles of species ages,diversification rates,contemporary environment,and conservatism to ancestral niches in shaping the i-LDG *** found Cycas experienced decreased diversification rates,coupled with the cooling temperature since its origin in the Eocene from continental *** regions have distinctively contributed to the formation of i-LDG for Cycas,with the northern hemisphere acting as evolutionary museums and the southern hemisphere serving as ***,water-related climate variables,specifically precipitation seasonality and potential evapotranspiration,were identified as paramount factors constraining Cycas species richness in the rainforest biome near the ***,the adherence to ancestral monsoonal climates emerges as a critical factor in sustaining the diversity *** study underscores the imperative of integrating both evolutionary and ecological approaches to comprehensively unravel the mechanisms underpinning global biodiversity patterns.

关键词： cycads latitudinal diversity gradient niche conservatism spatiotemporal diversification species richness

Design methodology of a mini-missile considering flight performance and guidance precision

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2024年第1期35卷 195-210页

作者： ZHANG Licong gong Chunlin SU Hua ANDREA Da Ronch Shaanxi Aerospace Flight Vehicle Design Key Laboratory School of AstronauticsNorthwestern Polytechnical UniversityXi’an 710072China Faculty of Engineering and Physical Sciences University of SouthamptonSouthampton SO171BJUnited Kingdom

The design of mini-missiles(MMs)presents several novel *** stringent mission requirement to reach a target with a certain precision imposes a high guidance *** miniaturization of the size of MMs makes the design of the guidance,navigation,and control(GNC)have a larger-thanbefore impact on the main-body design(shape,motor,and layout design)and its design objective,i.e.,flight *** a trade-off between flight performance and guidance precision,all the relevant interactions have to be accounted for in the design of the main body and the GNC ***,a multi-objective and multidisciplinary design optimization(MDO)is *** pertinent to motor,aerodynamics,layout,trajectory,flight dynamics,control,and guidance are included in the proposed MDO *** optimization problem seeks to maximize the range and minimize the guidance *** problem is solved by using the nondominated sorting genetic algorithm *** optimum design that balances a longer range with a smaller guidance error is ***,lessons learned about the design of the MM and insights into the trade-off between flight performance and guidance precision are given by comparing the optimum design to a design provided by the traditional approach.

关键词： mini-missiles(MMs) guidance navigation and control(GNC)system multi-objective optimization multidisciplinary design optimization(MDO) flight performance guidance precision

Simulation and Scale-up of Barium Sulphate Precipitation Process Using CFD Modeling

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2005年第2期13卷 167-172页

作者：龚俊波卫宏远王静康 John Garside School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Department of Chemical Engineering UMIST Manchester M601QD UK

Some empirical mixing models were used to describe the imperfect mixing in precipitation ***, the models can not, in general, reflect the details of interactions between mixing and crystallization in a vessel. In this study, CFD (computational fluid dynamics) technique were developed by simulating the precipitation of barium sulphate in stirred tanks by integration of population balance equations with a CFD solver. Two typical impellers, Rushton and pitched blade turbines, were employed for agitation. The influence of feed concentration and position on crystal product properties was investigated by CFD simulation. The scale-up of these precipitators was systematically studied. Significant effect on the crystal properties was found for the scale-up under some *** simulation, scale up, precipitation, CFD(computational fluid dynamics)

关键词：模拟技术硫酸钡 CFD模型流体动力学计算方法