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the Hoeke-Brown failure criterion and GSI-2018 edition

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Journal of Rock Mechanics and Geotechnical engineering 2019年第3期11卷 445-463页

作者： e.Hoek e.t.Brown North Vancouver British ColumbiaV7R 4H7Canada Brisbane Queensland 4169Australia

the HoekeBrown criterion was introduced in 1980 to provide input for the design of underground excavations in *** criterion now incorporates both intact rock and discontinuities,such as joints,characterized by the geological strength index(GSI),into a system designed to estimate the mechanical behaviour of typical rock masses encountered in tunnels,slopes and *** strength and deformation properties of intact rock,derived from laboratory tests,are reduced based on the properties of discontinuities in the rock *** nonlinear HoekeBrown criterion for rock masses is widely accepted and has been applied in many projects around the ***,in general,it has been found to provide satisfactory estimates,there are several questions on the limits of its applicability and on the inaccuracies related to the quality of the input *** paper introduces relatively few fundamental changes,but it does discuss many of the issues of utilization and presents case histories to demonstrate practical applications of the criterion and the GSI system.

关键词： Hoek-Brown criterion Geological strength index(GSI) Rock mass strength Uniaxial compressive strength(UCS) tension cut-off Rock mass deformation modulus

twenty years of Chinese vascular plant novelties,2000 through 2019

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Plant Diversity 2020年第5期42卷 393-398页

作者： Cheng du Shuai Liao David e.Boufford Jinshuang Ma Shanghai Chenshan Plant Science Research Center Chinese Academy of SciencesShanghai Chenshan Botanical GardenSongjiangShanghai201602China School of Life Sciences East China Normal UniversityMinhangShanghai200241China Harvard University Herbaria 22 Divinity AvenueCambridgeMA02138USA

From 2000 to 2019,11,895 new names or new additions to the Chinese vascular flora were proposed by 4226 individuals(4086 articles and 140 books),as documented in the Chinese Plant Names Index(CPNI).during those 20 years,4407 new taxa of vascular plants were described from China,including 7 new families,132 new genera,3543 new species,68 new subspecies,497 new varieties and 160 new ***,3562 new combinations and names at new rank and 306 new replacement names were also *** these various new names were 150 invalid names and 108 illegitimate names,including some that have not been *** hundred and forty three vascular plants were reported as new to China,while 2349 names were reduced to synonyms of 1406 *** data show that the Chinese flora increased in size at the rate of about 200 taxa annually during those *** the increased attention given to biodiversity in recent years,the evidence indicates that a large number of species in China have yet to be *** basic investigation of the Chinese flora is ***,in the past two decades only 8.5%of the newly published species have been based on molecular evidence,but in the past five years such data have increased significantly,reaching about 20%.Molecular data will undoubtedly become increasingly significant in the discovery of new species in the coming ***,Guangxi,Sichuan,Xizang and taiwan were important sources of new discoveries,with more than 3300 new taxa and records from these five *** area,taiwan and Hainan,two islands in southern China,have the highest density of newly discovered *** plant surveys are still needed,especially in areas in the southwest and on the southern islands.

关键词： Novelties of Chinese vascular plants Number of new taxa Number of new name changes Authors of new taxa

Reducing risks in the investigation, design and construction of large concrete dams

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Journal of Rock Mechanics and Geotechnical engineering 2017年第2期9卷 197-209页

作者： e.t.Brown Golder Associates Pty. Ltd. BrisbaneAustralia

An overview of the GeoSafe 2016 Symposium topic is provided using the example of large concrete dams for purposes of *** is essential that the risks associated with large dams be evaluated rigorously and managed proactively at all stages of their lives so that the risk of failure remains As Low As Reasonably Practicable(ALARP).Rock engineering features of large concrete dams that require particular attention,assessment and monitoring during the investigation,design,construction,initial filling,inservice operation,and subsequent repair and upgrade stages of the lives of concrete dams are identified and illustrated by examples from recorded experiences.A number of major concrete dam failures,including that of the *** dam,California,U.S.A.,in 1928,have led to significant developments in rock mechanics and rock engineering knowledge and techniques,as well as in dam design and review *** recent advances include a range of analytical,numerical modelling,probabilistic,reliability,failure mode and risk assessment approaches.

关键词： Concrete dam failure Dam engineering Risk assessment Rock engineering design Site investigation

An efficient Boron Source Activation Strategy for the Low‑temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng e Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNts)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNts at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNts.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

Automated classification of big X-ray diffraction data using deep learning models

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npj Computational Materials 2023年第1期9卷 169-180页

作者： Jerardo e.Salgado Samuel Lerman Zhaotong du Chenliang Xu Niaz Abdolrahim Materials Science program University of RochesterRochesterNew York 14627USA Department of Computer Science University of RochesterRochesterNew York 14627USA Department of Mechanical engineering University of RochesterRochesterNew York 14627USA Laboratory for Laser energetics University of RochesterRochesterNew York 14627USA

In current in situ X-ray diffraction(XRD)techniques,data generation surpasses human analytical capabilities,potentially leading to the loss of *** techniques require human intervention,and lack the performance and adaptability required for material *** the critical need for high-throughput automated XRD pattern analysis,we present a generalized deep learning model to classify a diverse set of materials’crystal systems and space *** our approach,we generate training data with a holistic representation of patterns that emerge from varying experimental conditions and crystal *** also employ an expedited learning technique to refine our model’s expertise to experimental *** addition,we optimize model architecture to elicit classification based on Bragg’s Law and use evaluation data to interpret our model’s *** evaluate our models using experimental data,materials unseen in training,and altered cubic crystals,where we observe state-of-the-art performance and even greater advances in space group classification.

关键词： Automate classify cubic

therapeutic potential of exercise-hormone irisin in Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1555-1564页

作者： eunhee Kim Rudolph etanzi Se Hoon Choi Genetics and Aging Research Unit MassGeneral Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMAUSA McCance Center for Brain Health Massachusetts General HospitalBostonMAUSA

Irisin is a myokine that is generated by cleavage of the membrane protein fibronectin type Ⅲ domain-containing protein 5(FNDC5) in response to physical exercise. Studies reveal that irisin/FNDC5 has neuroprotective functions against Alzheimer's disease, the most common form of dementia in the elderly, by improving cognitive function and reducing amyloid-β and tau pathologies as well as neuroinflammation in cell culture or animal models of Alzheimer's disease. Although current and ongoing studies on irisin/FNDC5 show promising results, further mechanistic studies are required to clarify its potential as a meaningful therapeutic target for alleviating Alzheimer's disease. We recently found that irisin treatment reduces amyloid-β pathology by increasing the activity/levels of amyloid-β-degrading enzyme neprilysin secreted from astrocytes. Herein, we present an overview of irisin/FNDC5's protective roles and mechanisms against Alzheimer's disease.

关键词： Alzheimer's disease exercise fibronectin typeⅢdomain-containing protein 5(FNDC5) irisin

Reduced Shell Model Calculations of ^111Sb and ^112Sb

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Chinese Physics Letters 2007年第6期24卷 1521-1524页

作者： e. Dikmen t, Akyǖrek Department of Physics Sǖleyman Demirel University Isparta Turkey

the low-lying states of the mid-heavy odd-even ^111Sb and odd-odd ^112Sb isotopes are calculated for the first time within the shell model framework. the shell model calculations have been carried out within the reduced model space including the single particle orbits ld5/2,097/2, ld3/2, 2Sl/2. We obtain the energy spectra for the ^111Sb and ^112Sb isotopes in the reduced model space by using CD-Bonn two-body effective nucleon-nucleon interaction. the energy spectra are compared to the experimental results to give some discussion about the low-lying states of ^111Sb and ^112Sb.

关键词： Calculations Reduced Model

Stem cells for cardiac repair: an introduction

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Journal of Geriatric Cardiology 2013年第2期10卷 186-197页

作者： Bastiaan C du Pr(e) Pieter A Doevendans Linda W van Laake Departments of Cardiology and Medical Physiology Division of Heart and Lungs University Medical Center Utrecht P.O. box 85500 3508 GA Utrecht the Netherlands Departments of Cardiology and Medical Physiology Division of Heart and Lungs University Medical Center Utrecht P.O. box 85500 3508 GA Utrecht the Netherlands Inter university Cardiology Institute of the Netherlands P.O. box 19258 2501 DG Utrecht the Netherlands Departments of Cardiology and Medical Physiology Division of Heart and Lungs University Medical Center Utrecht P.O. box 85500 3508 GA Utrecht the Netherlands Hubrecht Institute P.O box 85164 3508 AD Utrecht the Netherlands

Cardiovascular disease is a major cause of morbidity and mortality throughout the world. Most cardiovascular diseases, such as ischemic heart disease and cardiomyopathy, are associated with loss of functional cardiomyocytes. Unfortunately, the heart has a limited regenerative capacity and is not able to replace these cardiomyocytes once lost. In recent years, stem cells have been put forward as a potential source for cardiac regeneration. Pre-clinical studies that use stem cell-derived cardiac cells show promising results. the mechanisms,though, are not well understood, results have been variable, sometimes transient in the long term, and often without a mechanistic *** are still severalmajor hurdles to be taken. Stem cell-derived cardiac cells should resemble original cardiac cell types and be able to integrate in the damaged heart. Integration requires administration of stem cell-derived cardiac cells at the right time using the right mode of delivery. Once delivered, transplanted cells need vascularization, electrophysiological coupling with the injured heart, and prevention of immunological rejection. Finally, stem cell therapy needs to be safe, reproducible, and affordable. In this review, we will give an introduction to the principles of stem cell based cardiac repair.

关键词： Cardiomyocytes Heart Regeneration Stem cell

Precision bending of high-quality components for volume applications

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transactions of Nonferrous Metals Society of China 2010年第11期20卷 2100-2110页

作者： t.WeLO F.WIDeRe Department of engineering Design and Materials Norwegian University of Science and Technology(NTNU)

Recent new technology developments were presented in the field of industrial bending operations,including flexible stretch forming and 3D rotary stretch *** were made to give an overview of different mechanisms that influence dimensional accuracy,including local cross-sectional deformations such as suck-in and volume conservation effects,along with global deformations such as *** analytical model was developed to determine the particular influence of different material,geometry and process parameters on dimensional variability of bent *** results were discussed in terms of overall process capability(Cp) and associated process *** results show that different governing mechanisms prevail in various bending operations,meaning that attention has to be placed on controlling those process parameters that really are important to part quality in each specific *** strategies may be defined for reducing *** alternative may be to design more robust process and tool technology that reduce the effect of upstream parameters on dimensional variability of the formed *** results show that optimal tool design and technology may in specific cases improve the dimensional accuracy of a formed *** on the findings discussed herein,it is concluded that advances in industrial bending operations require focus on improving the understanding of mechanical mechanisms,including models and parameter development,new technology developments,including process,tool,measurement and control capabilities,and process discipline at the shop floor,combined with a basic philosophy of controlling process parameters rather than part attributes.

关键词： bending technology tools dimensional accuracy distortions springback formability