检索结果-南通市图书馆

Laser cut hole matrices in novel armour plate steel for appliqué battlefield vehicle protection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2016年第5期12卷 351-359页

作者： daniel j. THOMAS Engineering Manufacturing Centre College of Engineering Swansea University Swansea UK

During this research, experimental rolled homogeneous armour steel was cast, annealed and laser cut to form an appliqué plate. This Martensitic–Bainitic microstructure steel grade was used to test a novel means of engineering lightweight armour. It was determined that a laser cutting speed of 1200 mm/min produced optimum hole formations with limited distortion. The array of holes acts as a double-edged solution, in that they provide weight saving of 45%, providing a protective advantage and increasing the surface area. Data collected were used to generate laser cut-edge hole proj.ctions in order to identify the optimum cutting speed, edge condition, cost and deformation performance. These parameters resulted in the generation of a surface, with less stress raising features. This can result in a distribution of stress across the wider surface. Provided that appropriate process parameters are used to generate laser cut edges, then the hardness properties of the surface can be controlled. This is due to compressive residual stresses produced in the near edge region as a result of metallurgical transformations. This way the traverse cutting speed parameter can be adj.sted to alter critical surface characteristics and microstructural properties in close proximity to the cut-edge. A relationship was identified between the width of the laser HAZ and the hardness of the cut edge. It is the thickness of the HAZ that is affected by the laser process parameters which can be manipulated with adj.sting the traverse cutting speed.

关键词： Armour steels Defence systems Steel processing Armour engineering

Design of synthetic materials for intracellular delivery of RNAs： From siRNA-mediated gene silencing to CRISPR/Cas gene editing

在线全文

学校读者我要写书评

暂无评论

Nano Research 2018年第10期11卷 5310-5337页

作者： j.son B. Miller daniel j. Siegwart Simmons Comprehensive Cancer Center University of Texas Southwestern Medical Center Dallas TX 75390 USA Department of Biochemistry University of Texas Southwestern Medical Center Dallas TX 75390 USA

Ribonucleic acids （RNAs） possess great therapeutic potential and can be used to treat a variety of diseases. The unique biophysical properties of RNAs, such as high molecular weight, negative charge, hydrophilicity, low stability, and potential immunogenicity, require chemical modification and development of carriers to enable intracellular delivery of RNAs for clinical use. A variety of nanornaterials have been developed for the effective in vivo delivery of short/ small RNAs, messenger RNAs, and RNAs required for gene editing technologies including clustered regularly interspaced palindromic repeat （CRISPR）/Cas. This review outlines the challenges of delivering RNA therapeutics, explores the chemical synthesis of RNA modifications and carriers, and describes the efforts to design nanomaterials that can be used for a variety of clinical indications.

关键词： nucleic acid therapeutics nanoparticles synthetic nanomaterials RNA interference (RNAi) messenger RNA (mRNA) clustered regularly inter-spaced palindromic repeat(CRISPR)/Cas

Periodic Orbits in Rotating Second Degree and Order Gravity Fields

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 j.urnal of Astronomy and Astrophysics 2008年第1期8卷 108-118页

作者： Wei-Duo Hu daniel j. Scheeres School of Astronautics BeiHang University Beijing 100083 Department of Aerospace Engineering The University of Michigan Ann Arbor MI48109 USA

Periodic orbits in an arbitrary 2nd degree and order uniformly rotating gravity field are studied. We investigate the four equilibrium points in this gravity field. We see that close relation exists between the stability of these equilibria and the existence and stability of their nearby periodic orbits. We check the periodic orbits with non-zero periods. In our searching procedure for these periodic orbits, we remove the two unity eigenvalues from the state transition matrix to find a robust, non-singular linear map to solve for the periodic orbits. The algorithm converges well, especially for stable periodic orbits. Using the searching procedure, which is relatively automatic, we find five basic families of periodic orbits in the rotating second degree and order gravity field for planar motion, and discuss their existence and stability at different central body rotation rates.

关键词： celestial / orbital mechanics - asteroid - periodic orbit - resonance

Effect of matrix-nanoparticle interactions on recognition of aryldiazonium nanoparticle-imprinted matrices

在线全文

学校读者我要写书评

暂无评论

Nano Research 2019年第2期12卷 265-271页

作者： Netta Bruchiel-Spanier Linoy Dery Noam Tal Shahar Dery Elad gross daniel Mandler Institute of Chemistry The Hebrew University of Jerusalem Jerusalem 9190401 Israel

The selective recognition of nanoparticles (NPs) can be achieved by nanoparticle-imprinted matrices (NAIMs),where NPs are imprinted in a matrix followed by their removal to form voids that can reuptake the original *** recognition depends on supramolecular interactions between the matrix and the shell of the NPs,as well as on the geometrical suitability of the imprinted voids to accommodate the ***,gold NPs stabilized with citrate (AuNPs-cit) were preadsorbed onto a conductive surface followed by electrografting of p-aryldiazonium salts (ADS) with different functional *** thickness of the matrix was carefully controlled by altering the scan *** AuNPs-cit were removed by electrochemical *** recognition of the NAIMs was determined by the reuptake of the original AuNPs-cit by the imprinted *** found that the recognition efficiency is a function of the thickness of the NAIM layer and is sensitive to the chemical structure of the ***,a subtle change of the functional group of the p-aryldiazonium building block,which was varied from an ether to an ester,significantly affected the recognition of the NPs.

关键词： diazonium salt nanoparticles imprinting electrochemistry focused ion beam

RULEMAKING POSSIBILITIES： EFFORTS OF THE UNITED STATES j.DICIAL CONFERENCE ADVISORY COMMITTEE ON EVIDENCE RULES TO ADDRESS THE CHALLENGES TO FORENSIC EXPERT TESTIMONY

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Law in China-Selected Publications from Chinese Universities 2018年第1期13卷 34-42页

作者： daniel j. Capra School of Law University of California Berkeley USA Reed Professor School of Law Fordharn University New York 10023 USA

This piece is an echo to one of the main subj.cts of the Sixth International Conference on Evidence Law and Forensic Science which is to determine what evidentiary reforms are necessary for regulating forensic expert testimony, and how those reforms might be implemented. In United States, the predominant way of evidentiary reform is through rulemaking. As the Reporter of j.dicial Conference Advisory Committee on the Federal Rules of Evidence since 1996, the author, with a pragmatic spirit throughout the article, examines such an effort at the federal level of U.S. in six parts （levels）, starting from the most general, abstract level till fmishing with the most detailed and substantive points. Part I begins with a brief introduction of the hierarchies of evidentiary rulemaking authorities at the federal level of the United States, various interested groups and their interesting interactions in the rulemaking process. The author then shifts to the general topic of writing rules with a specific focus on the level of detail that is to be provided in doing so; Part II further narrows down the scrutiny into writing a rule on forensic expert testimony with an emphasis on the necessity of making such a rule change to the current general standards of FRE; Part III directly addresses the challenges of drafting a rule on forensic evidence in FRE, including a comparation of various alternative drafting models; Part IV and Part V respectively discusses the Reporter＇s comments and the j.stice Department＇s concerns over the drafted rules; and Part VI briefly discusses the feasibility and effectiveness of a Best Practices Manual on forensic evidence in lieu of rulemaking.

关键词： forensics rulemaking reliability expert

Towards maximized utilization of iridium for the acidic oxygen evolution reaction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2019年第9期12卷 2275-2280页

作者： Marc Ledendecker Simon Geiger Katharina Hengge j.ohyun Lim Serhiy Cherevko Andrea M. Mingers daniel Gohl Guilherme V. Fortunato daniel j.lalpoor Ferdi Schuth Christina Scheu Karl j. j. Mayrhofer Department of Interface Chemistry and Surface Engineering Nanoanalytics and Interfaces Max-Planck-Institut fur Eisenforschung GmbH40237 DusseldorfGermany Department of Heterogeneous Catalysis Max-Planck-Institut fur KohlenforschungKaiser- Wilhelm-Platz 145470 Mulheim an der RuhrGermany Helmholtz-Institute Erlangen-Nurnbergfar Renewable Energy (IEK-11) Forschungszentrum Jillich91058 ErlangenGermany Department of Chemical and Biological Engineering Friedrich-Alexander- Universitat Erlangen -Nurnberg91058 ErlangenGermany Institute of Chemistry Universidade Federal de Mato Grosso do SulAv. Senador Filin to Muller1555Campo GrandeMS 79074-460Brazil

The reduction in noble metal content for efficient oxygen evolution catalysis is a crucial aspect towards the large scale commercialisation of polymer electrolyte membrane *** catalytic stability and activity are inversely related,long service lifetime still demands large amounts of low-abundant and expensive *** this manuscript we elaborate on the concept of maximizing the utilisation of iridium for the oxygen evolution *** combining different tin oxide based support materials with liquid atomic layer deposition of iridium oxide,new possibilities are opened up to grow thin layers of iridium oxide with tuneable noble metal ***-situ,time-and potential-resolved dissolution experiments reveal how the stability of the substrate and the catalyst layer thickness directly affect the activity and stability of deposited iridium *** on our results,we elaborate on strategies how to obtain stable and active catalysts with maximized iridium utilisation for the oxygen evolution reaction and demonstrate how the activity and durability can be tailored *** results highlight the potential of utilizing thin noble metal films with earth abundant *** for future catalytic applications in the energy sector.

关键词： oxygen evolution reaction liquid atomic layer depositi on catalysis iridium core-shell nano particles

Avalonia,get bent!–Paleomagnetism from SW Iberia confirms the Greater Cantabrian Orocline

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geoscience Frontiers 2021年第2期12卷 805-825页

作者： Bruno daniel Leite Mendes daniel Pastor-Galan Mark j.Dekkers Wout Krij.sman Paleomagnetic Laboratory Fort Hoofddij. Department of Earth SciencesUtrecht UniversityBudapestlaan 173584CDthe Netherlands Frontier Research Institute for Interdisciplinary Sciences Tohoku UniversityJapan Department Earth Science Tohoku UniversityJapan Center for North East Asia Studies Tohoku University980-857641 KawauchiAoba-kuSendaiMiyagiJapan

The amalgamation of Pangea formed the contorted Variscan-Alleghanian orogen,suturing Gondwana and Laurussia during the *** all swirls of this orogen,a double curve in Iberia stands out,the coupled Cantabrian Orocline and Central Iberian *** Cantabrian Orocline formed at ca.315–290 Ma subsequent to the Variscan *** formation mechanism of the Cantabrian Orocline is disputed,the most commonly proposed mechanisms include either(1)that south-westernmost Iberia would be an Avalonian(Laurussian)indenter or(2)that the stress field changed,buckling the *** contrast,the geometry and kinematics of the Central Iberian curve are largely *** some authors defend both curvatures are genetically linked,others support they are distinct and formed at different *** uncertainty adds an extra layer of complexity to our understanding of the final stages of Pangea’s *** solve these issues,we study the late Carboniferous–early Permian vertical-axis rotations of SW Iberia with *** results show up to 70counterclockwise vertical-axis rotations during late Carboniferous times,concurring with the anticipated kinematics if SW Iberia was part of the southern limb of the Cantabrian *** results do not allow the necessary penecontemporaneous clockwise rotations in Central Iberia to support a concomitant formation of both Cantabrian and Central Iberian *** coherent rotation of both Gondwanan and Avalonian pieces of SW Iberia discards the Laurussian indenter hypothesis as a formation mechanism of the Cantabrian Orocline and confirms the Greater Cantabrian Orocline *** Greater Cantabrian Orocline likely formed as a consequence of a change in the stress field during the late Carboniferous and extended beyond the Rheic Ocean suture affecting the margins of both Laurussia and Gondwana.

关键词： Pangea Variscan orogeny Greater Cantabrian Orocline Paleomagnetism Central Iberian curve

Network analysis to inform invasive species spread among lakes

在线全文

学校读者我要写书评

暂无评论

j.urnal of Oceanology and Limnology 2019年第3期37卷 1037-1041页

作者： ESCOBAR Luis E. ROMERO-ALVAREZ daniel LARKIN daniel j. PHELPS Nicholas B. D. Department of Fish and Wildlife Conservation Virginia TechBlacksburgVirginiaUSA Department of Ecology and Evolutionary Biology-Biodiversity Institute University of KansasLawrenceUSA Department of Fisheries Wildlifeand Conservation BiologyUniversity of MinnesotaSt.PaulMinnesotaUSA Minnesota Aquatic Invasive Species Research Center University of MinnesotaSt.PaulMinnesotaUSA

Often facilitated by human-mediated pathways,aquatic invasive species are a threat to the health and biodiversity of global *** present a novel approach incorporating survey data of watercraft movement in a social network analysis to reconstruct potential pathways of aquatic invasive species spread between *** an example,we use the green alga Nitellopsis obtusa,also known as starry stonewort,an aquatic invasive species affecting the Great Lakes region in the United States and *** movement of algal fragments via human-mediated pathways(i.e.,watercraft)has been hypothesized as the primary driver of starry stonewort *** used survey data collected at boat ramps during the 2013 and 2014 openwater seasons to describe the flow of watercraft from Lake Koronis,where *** was first detected in Minnesota,to other lakes in the *** results suggest that the risk of *** expansion is not highly constrained by geographic proximity and management efforts should consider highly connected *** human movement via network analysis may help to explain past and future routes of aquatic invasive species infestation between lakes and can improve evidence-based prevention and control efforts.

关键词： Nitellopsis obtusa starry stonewort lake network invasion

Tsc2 mutation induces renal tubular cell nonautonomous disease

在线全文

学校读者我要写书评

暂无评论

Genes & Diseases 2022年第1期9卷 187-200页

作者： Prashant Kumar Fahad Zadj.li Ying Yao daniel j.hnson Brian Siroky Aristotelis Astrinidis Peter Vogel Kenneth W.gross j.hn j.Bissler Department of Pediatrics University of Tennessee Health Science Center and Le Bonheur Children's HospitalMemphisTN 38103USA Children's Foundation Research Institute(CFRI) Le Bonheur Children's HospitalMemphisTN 38105USA Department of Clinical Biochemistry College of Medicine&Health SciencesSultan Qaboos UniversityMuscat 123Oman Molecular Bioinformatics Center University of Tennessee Health Science CenterMemphisTN 38163USA Department of Veterinary Pathology St.Jude Children's Research HospitalMemphisTN 38105USA Department of Molecular and Cellular Biology Roswell Park Comprehensive Cancer CenterBuffaloNY 14263USA Pediatric Medicine Department St.Jude Children's Research HospitalMemphisTN 38105USA

TSC renal cystic disease is poorly understood and has no approved *** a new principal cell-targeted murine model of Tsc cystic disease,the renal cystic epithelium is mostly composed of type A intercalated cells with an intact Tsc2 gene confirmed by sequencing,although these cells exhibit a Tsc-mutant disease *** used a newly derived targeted murine model in lineage tracing and extracellular vesicle(EV)characterization experiments and a cell culture model in EV characterization and cellular induction experiments to understand TSC *** lineage tracing experiments,we found principal cells undergo clonal expansion but contribute very few cells to the *** determined that cystic kidneys contain more interstitial EVs than noncystic kidneys,excrete fewer EVs in urine,and contain EVs in cyst ***,the loss of Tsc2 gene in EV-producing cells greatly changes the effect of EVs on renal tubular epithelium,such that the epithelium develops increased secretory and proliferative pathway *** demonstate that the mTORC1 pathway activity is independent form the EV production,and that the EV effects for a single cell line can vary *** cystogenesis involves significant contribution from genetically intact cells conscripted to the mutant phenotype by mutant cell derived EVs.

关键词： Cell nonautonomous trait Polycystic kidney disease Renalcystogenesis Tuberous sclerosis complex