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Recent advances in nanomaterials for high-performance Li–S batteries

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Journal of Energy Chemistry 2020年第8期29卷 86-106,I0004页

作者： james E.Knoop Seongki Ahn Joint School of nanoscience and nanoengineering North Carolina Agricultural and Technical State UniversityGreensboroNC 27401USA Research Organization for nano and Life Innovation Waseda University513WasedatsurumakichoShinjuku-kuTokyo 162-0041Japan

This article reviews nanotechnology as a practical solution for improving lithium-sulfur batteries. Lithiumsulfur batteries have been widely examined because sulfur has many advantageous properties such as a high crustal abundance, low environmental impact, low cost, high gravimetric(2600 W h kg-1) and volumetric(2800 W h L-1) energy densities, assuming complete conversion of sulfur to lithium sulfide(Li2S)upon lithiation. However, lithium-sulfur batteries have not yet reach commercialization due to demerits involving the formation of soluble lithium polysulfides(Li2Sn, n=3–8), low electrical conductivity, and low loading density of sulfur. These issues arise mainly due to the polysulfide shuttle phenomenon and the inherent insulating nature of sulfur. To overcome these issues, strategies have been pursued using nanotechnology applied to porous carbon nanocomposites, hollow one-dimensional carbon nanomaterials, graphene nanocomposites, and three-dimensional carbon nanostructured matrices. This paper aims to review various solutions pertaining to the role of nanotechnology in synthesizing nanoscale and nanostructured materials for advanced and high-performance lithium–sulfur batteries. Furthermore, we highlight perspective research directions for commercialization of lithium–sulfur batteries as a major power source for electric vehicles and large-scale electric energy storage.

关键词： nanotechnology Lithium–sulfur batteries Carbon nanomaterials nanocomposite sulfur 3D nanostructured materials

A planar defect spin sensor in a two-dimensional material susceptible to strain and electric fields

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npj Computational Materials 2023年第1期9卷 775-782页

作者： Péter Udvarhelyi Tristan Clua-Provost Alrik Durand Jiahan Li james H.Edgar Bernard Gil Guillaume Cassabois Vincent Jacques Adam Gali Wigner Research Centre for Physics P.O.Box 49H-1525 BudapestHungary Budapest University of Technology and Economics Institute of PhysicsDepartment of Atomic PhysicsMűegyetem rakpart 3.1111 BudapestHungary Laboratoire Charles Coulomb Universitéde Montpellier and CNRS34095 MontpellierFrance Tim Taylor Department of Chemical Engineering Kansas State UniversityManhattanKS 66506USA

The boron-vacancy spin defect(V_(B)^(-))in hexagonal boron nitride(hBn)has a great potential as a quantum sensor in a two-dimensional material that can directly probe various external perturbations in atomic-scale proximity to the quantum sensing ***,we apply first-principles calculations to determine the coupling of the VB electronic spin to strain and electric *** work unravels the interplay between local piezoelectric and elastic effects contributing to the final response to the electric *** theoretical predictions are then used to analyse optically detected magnetic resonance(ODMR)spectra recorded on hBn crystals containing different densities of V_(B)^(-) *** prove that the orthorhombic zero-field splitting parameter results from local electric fields produced by surrounding charge *** work paves the way towards applications of V_(B)^(-) centres for quantitative electric field imaging and quantum sensing under pressure.

关键词： defect quantum boron

Distribution of ^3H—nicotine in Rat Tissues Under the Influence of Simulated Microgravity

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Biomedical and Environmental Sciences 1999年第2期12卷 103-109页

作者： PARIMAL CHOWDHURY MICHAEL E. SOULSBY AnD james n. PASLEY (Department of Physiology and Biophysics, University of Arkansas for Medical Scienses, Little Rock, Arkansas 72205, USA) Univeristy of Arkansas for Medical Sciences 美国

Rat tail suspension offers a useful model to reproduce physiologic responses to *** present study was conducted in the head-down-tilt(HDT) rat model to assess changes in metabolism of body tissues employing 3H-nicotine. Twelve male rats were used in the study. Half of the rats were tail suspended at 30°for two weeks on a 12/12 light/dark cycle. During this period,body weight, food and fluid intakes were measured. At term, animals were anesthetized and injected IV withe a solution contaming 4 microuries of micotine. After 90 min the animals were sacrificed, exsanguinated and tissues (brain,blood,trachea,salivary gland,lung,heart,esophagus,spleen, kidneys and testes) were harvested. The distribution of 3H-nicotine per gram of each tissue was determinded and ealeulated as percent of total injected radioactivity. Final body weights of suspended ammals were significantly (P n those of eontrols(309±21 vs 350±11g). 3Hnicotine waw retained in greatest amounts by the kindneys, followed inorder by salivary glands, spleen, and gastrointestinal tissues. compared to non-suspended control, the tissue retention of nicotine in suspended animals was decreased in the following tissues:esphyagus (25 %), aorta (25%). fundus (25%), trachea (22%), adrenals (18%), spleen (17 %), and pancreas (12 %). The decreased retention of mcotine in tissues from suspended animals may be indicative of the fluid shifts and changes in blood flow to those tissue beds. The lack of differnces in nicotine retention in liver and kidney between control and suspended groups may implicate a normal metabolic function of these organs even under simulated weightlessness.

关键词： Gravitation Animals Male nicotine Rats Rats, Sprague-Dawley Research Support, non-U.S. Gov't Tissue Distribution Tritium Weightlessness Simulation

The global nitrogen cycle:Past,present and future

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Science China(Life Sciences) 2005年第Z2期48卷 669-677页

作者： james n.Galloway Environmental Sciences Department University of Virginia Charlottesville Virginia 22904USA

Food and energy production converts n2 to reactive n species that cascade through environmental reservoirs and in the process impact human and ecosystem health. This presentation will examine the impact of increased n mobilization on the global n cycle by contrasting n distribution in the late-19th century with those of the late-20th century. The presentation will give a general overview of regional differences and will conclude with a projection of the global n cycle for 2050.

关键词： global n cycle, human nr creation, n budgets, consquences of n cycle alteration.

A comparison of the relative efficiency of ICSI and extended culture with epididymal sperm versus testicular sperm in patients with obstructive azoospermia

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Asian Journal of Andrology 2020年第2期22卷 222-226页

作者： Scott J Morin Brent M Hanson Caroline R Juneau Shelby A neal Jessica n Landis Richard T Scott Jr james M Hotaling Reproductive Medicine Associates of new Jersey 140 Allen RoadBasking RidgeNJ 07920USA Division of Reproductive Endocrinology and Infertility Department of Obstetrics and GynecologySidney Kimmel Medical College at Thomas Jefferson University833 Chestnut StreetPhiladelphiaPA 19107USA Foundation for Embryonic Competence 140 Allen RoadBasking RidgeNJ 07920USA Division of Urology Department of SurgeryUniversity of Utah School of Medicine30 N 1900 ESalt Lake CityUT 84132USA Department of Obstetrics and Gynecology University of Utah School of Medicine30 N 1900 ESalt Lake CityUT 84132USA.An abbreviated version of this manuscript was published and presented as an abstract at the American Society for Reproductive Medicine(ASRM)2017 Scientific Congress.

This is a retrospective cohort study comparing blastocyst transfer outcomes following intracytoplasmic sperm injection utilizing epididymal versus testicular sperm for men with obstructive *** cases at a single center between 2012 and 2016 were *** approach was selected at the surgeon’s discretion and included microepididymal sperm aspiration or testicular sperm *** culture was exclusively utilized prior to *** primary outcome was live birth *** outcomes included fertilization rate,blastulation rate,euploidy rate,and implantation rate.A mixed effects model was ***-six microepididymal sperm aspiration cases and 93 testicular sperm extraction cases were *** live birth rate was equivalent(48.6%vs 50.5%,P=0.77).However,on mixed effects model,epididymal sperm resulted in a greater likelihood of fertilization(adjusted OR:1.37,95%CI:1.05–1.81,P=0.02)and produced a higher blastulation rate(adjusted OR:1.41,95%CI:1.1–1.85,P=0.01).As a result,the epididymal sperm group had more supernumerary blastocysts available(4.3 vs 3,Pno *** rates were no different through the first transfer ***,intracytoplasmic sperm injection following microepididymal sperm aspiration resulted in a greater number of usable blastocysts per ***,the true benefit of epididymal sperm may only be demonstrated via a comparison of cumulative pregnancy rates after multiple transfers from one cohort.

关键词： azoospermia intracytoplasmic sperm injection male infertility testicular sperm extraction

Relating environmental variables with aquatic community structure in an agricultural/urban coldwater stream

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Ecological Processes 2021年第1期10卷 481-499页

作者： Daniel T.L.Myers Richard R.Rediske james n.Mcnair Aaron D.Parker E.Wendy Ogilvie Annis Water Resources Institute Grand Valley State University740 W Shoreline DriveMuskegonMI 49401USA. Michigan Department of Environment Great Lakesand Energy525 W Allegan StreetLansingMI 48909USA. Grand Valley Metropolitan Council 678 Front Avenue NWSuite 200Grand RapidsMI 49504USA.

Background:Urban areas are often built along large rivers and surrounded by agricultural *** may lead to small tributary streams that have agricultural headwaters and urbanized lower *** study objectives assessed are as follows:(1)landscape,geomorphic,and water quality variables that best explained variation in aquatic communities and their integrity in a stream system following this agricultural-to-urban land use gradient;(2)ways this land use gradient caused aquatic communities to differ from what would be expected for an idealized natural stream or other longitudinal gradients;and(3)whether the impacts of this land use gradient on aquatic communities would grow larger in a downstream direction through the agricultural and urban *** study area was an impaired coldwater stream in Michigan,***:Many factors structured the biological communities along the agricultural-to-urban land use *** woody debris had the strongest relationship with EPT(Ephemeroptera,Plecoptera,and Trichoptera)abundance and richness and were most common in the lower,urbanized *** streambed substrate had the strongest relationship with Diptera taxa and surface air breather macroinvertebrates and was dominant in agricultural *** community assemblage was influenced largely by stream flow and temperature regimes,while poor fish community integrity in lower urban reaches could be impacted by geomorphology and episodic urban pollution *** macroinvertebrates were most abundant in deforested,first-order agricultural headwaters,while EPT macroinvertebrate richness was the highest downstream of agricultural areas within the urban zone that had extensive forest ***:Environmental variables and aquatic communities would often not conform with what we would expect from an idealized natural *** richness improved downstream of agricultural *** shows promise for the recovery of aquatic systems using we

关键词： Land use Habitat Stream Fish Macroinvertebrate Gradient

The Interaction of Spinach nitrite Reductase with Ferredoxin： A Site-Directed Mutation Study

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Molecular Plant 2009年第3期2卷 407-415页

作者： Masakazu Hirasawa Jatindra n. Tripathy Ramasamy Somasundaram Michael K. Johnson Megha Bhalla james R Allen David B. Knaff Department of Chemistry and Biochemistry Texas Tech University Lubbock TX 79409-1061 USA Department of Chemistry University of Georgia Athens GA 30602 USA Department of Chemistry and Biochemistry Arizona State University Tempe AZ 85287-1604 USA Institute for Biotechnology and Genomics Texas Tech University Lubbock TX 79409-1061 USA

A series of site-directed mutants of the ferredoxin-dependent spinach nitrite reductase has been characterized and several amino acids have been identified that appear to be involved in the interaction of the enzyme with ferredoxin. In a complementary study, binding constants to nitrite reductase and steady-state kinetic parameters of site-directed mutants of ferredoxin were determined in an attempt to identify ferredoxin amino acids involved in the interaction with nitrite reductase. The results have been interpreted in terms of an in-silico docking model for the 1：1 complex of ferredoxin with nitrite reductase.

关键词： Electron transport enzymology nitrogen metabolism molecular biology.

Isolated left ventricular apical hypoplasia:Systematic review and analysis of the 37 cases reported so far

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世界临床病例杂志 2023年第23期11卷 5494-5503页

作者： Pier Paolo Bassareo Sophie Duignan Adam james Esme Dunne Colin J McMahon Kevin P Walsh University College of Dublin School of Medicine and Department of Cardiology at Mater Misericordiae University HospitalDublin D07 R2WYIreland Department of Cardiology Children's Health CrumlinDublin D12 N512Ireland University College of Dublin School of Medicine and Department of CardiologyChildren's Health IrelandDublin D12 N512Ireland

BACKGROUnD Isolated left ventricular apical hypoplasia(ILVAH),also known as truncated left ventricle(LV),is a very unusual *** is characterised by a truncated,spherical,and non-apex forming *** true apex is occupied by the right *** to the rarity of the disease,just a few case reports and limited case series have been published in the *** To analysing the so far 37 reported ILVAH cases *** The electronic databases PubMed and Scopus were investigated from their establishment up to December 13,*** The majority of cases reported occurred in males(52.7%).Mean age at diagnosis was 26.1±19.6 *** than a third of the patients were asymptomatic(35.1%).The most usual clinical presentation was breathlessness(40.5%).The most commonly detected electrocardiogram changes were T wave abnormalities(29.7%)and right axis deviation with poor R wave progression(24.3%).Atrial fibrillation/flutter was detected in 24.3%.Echocardiography was performed in 97.3%of cases and cardiac MRI in 91.9%of *** fraction was reduced in more than a half of patients(56.7%).An associated congenital heart disease was found in 16.2%.Heart failure therapy was administered in 35.1%of *** outcome was favorable in the vast majority of patients,with just one *** ILVAH is a multifaceted entity with a so far unpredictable course,ranging from benign until the elderly to sudden death during adolescence.

关键词： Isolated left ventricular apical hypoplasia Truncated left ventricle Electrocardiography Echocardiography Cardiac magnetic resonance imaging Heart failure

Unintended nutrient imbalance induced by wastewater effluent inputs to receiving water and its ecological consequences

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Frontiers of Environmental Science & Engineering 2022年第11期16卷 273-275页

作者： Yindong Tong Xuejun Wang james J.Elser School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Flathead Lake Biological Station University of MontanaPolsonMT 59860USA

Eutrophication is the most widespread water quality issue *** date,most efforts to control eutrophication have focused on reductions of external nutrient inputs,yet importance of nutrient stoichiometry and subsequent shift in plankton composition in aquatic ecosystem has been largely *** address eutrophication,improved sanitation is one of the United nations Sustainable Development Goals,spurring the constructions of wastewater treatment facilities that have improved water quality in many lakes and ***,control measures are often targeted at and effective in removing a single nutrient from sewage and thus are less effective in removing the others,resulting in the changes of nutrient *** general,more effective phosphorus removal relative to nitrogen has occurred in wastewater treatment leading to substantial increases in n/P ratios in effluent relative to the ***,high n/P ratios in receiving waters can impose negative influences on ***,longterm strategies for domestic wastewater management should not merely focus on the total reduction of nutrient discharge but also consider their stoichiometric balances in receiving waters.

关键词： nutrient stoichiometry Wastewater treatment Ecosystem functioning Water quality management