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Chemical Research in Chinese Universities 2004年第4期20卷 411-416页

作者： LAI X. MA C. k. J. robert M. C. Miller Institute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsCCLRC Daresbury Laboratory Daresbury Leeds LS2 9JT UKLeeds LS2 9JT UKLeeds LS2 9JT UKWarrington Cheshire WA4 4AD UK

A novel crystal characterization instrument has been built up in which a combination of X-ray multiple diffraction and X-ray topography is applied to enabling the cross-correlation between micro-crystallographic symmetry and its spatial dependence in relation to lattice defects. This facility is used to examine, in a self-consistent manner, growth sector-dependant changes to both the crystallographic structure and the lattice defects associated with the action of habit-modifying additives in a number of representative crystal growth systems. In addition, the new instrument can be used to probe micro-crystallographic aspects(such as distortion to crystal symmetry) and relate these in a spatially resolved manner to the crystal defect structure in crystals doped with known habit modifiers.

关键词： X-ray diffraction X-ray multiple diffraction X-ray topography Habit modification Crystal growth Growth defects

Analysis of the Sloshing Flows of a LNG Cargo Tank

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Journal of Thermal Science 2011年第5期20卷 442-448页

作者： Deog Hee Doh Hyo Je Jo Byeong Rog Shin Min Cheol ryu Yoon Sik Hwang Division of Mechanical and Information Eng. Korea Maritime University Division of Naval Architecture and Ocean Systems Eng. Korea Maritime University Department of Mechanical Engineering Changwon National University Fluid Dynamics R&D Team DSMEGeoje-siKorea

The sloshing flows in a LNG cargo tank model （1/50 scale） of a ship are measured by an embedded pano- ramicPIV system. The measurement system consists of a Nd-Yag laser（120mJ, 15Hz）, two cameras（lk x lk） and a host computer. Four experimental cases were tested for the tank model, in which swaying motions are made by a 6 DOF-motion platform. The amplitudes of swaying are 9.76mm and 29.29mm, and the swaying frequencies are 0.633Hz and 0.828Hz. The measurement regions are the vertical plane 50ram away from the front wall of the tank where a pump tower is installed. It was verified that the flow patterns of the sloshing are similar to each other when the swaying amplitudes are similar.

关键词： Sloshing Model Ship Cargo Tank Embedded Panoramic PIV Swaying Motion

Hurricane disturbances, tree diversity, and succession in North Carolina Piedmont forests, USA

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Journal of Forestry Research 2019年第1期30卷 219-231页

作者： Weimin Xi robert k.Peet Michael T.Lee Dean L.Urban Department of Biology University of North Carolina at Chapel Hill Department of Biological and Health Sciences Texas A & M University-Kingsville The Nicholas School of the Environment Duke University

Windthrow plays a critical role in maintaining species diversity in temperate forests. Do large-scale strong wind events(i.e., tropical cyclones, including hurricanes,typhoons and severe cyclonic storms) increase tree diversity in severely damaged forest areas? Do hurricanes(tropical cyclones that occurs in the Atlantic Ocean and northeastern Pacific Ocean) lead to altered relative abundance of shade-tolerant and shade-intolerant species? Did historic hurricanes alter the succession trajectory of the damaged forests? We used nearly 70-year tree demographic data to assess the effects of two major hurricanes on woody species diversity in Piedmont forests, North Carolina, USA. Species richness(S) and Shannon–Wiener's diversity index(H') were used to evaluate the changes in tree diversity. The changes in composition were assessed with Nonmetric Multidimensional Scaling. The pre-hurricane successional phase can strongly influence both the damage severity and subsequent responses. Although there is often an immediate drop in diversity following a hurricane, understory tree diversity quickly increases to levels that exceed those prior to the disturbance. This leads to an increase in diversity in stands that were substantially damaged. Hurricanes significantly decrease the dominance of shade-intolerant canopy species while increasing preestablished, more shade-tolerant species. We conclude that large, and infrequent hurricanes help to maintain local tree diversity, but also accelerate the increase in dominance of understory species such as red maple and beech.

关键词： Wind disturbance Tree species diversity Plant succession Disturbance-diversity relationship Piedmont forests

Effect of oat hulls as a free choice feeding on broiler performance,short chain fatty acids and microflora under a mild necrotic enteritis challenge

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Animal Nutrition 2018年第1期4卷 65-72页

作者： Sarbast k.kheravii robert A.Swick Mingan Choct Shu-Biao Wu Animal Science School of Environmental and Rural ScienceUniversity of New England Animal Production Faculty of Agriculture and ForestryUniversity of Duhok

Structure of fibre has been reported to enhance performance,intestinal function and modify the composition and quantity of the microbial population in the chicken gastrointestinal *** is hypothesised that insoluble fibre in oat hulls may improve gut health and reduce intestinal Clostridium perfringens *** research assessed the effect of free choice oat hulls(OH) on performance and gut microbiota in broilers during a mild(subclinical) necrotic enteritis(NE) challenge.A total of 240 dayold male Ross 308 broiler chickens were assigned to 24 cages in a 2×2 factorial arrangement of *** were challenge - or +; and OH - or +.On d 16,challenged broilers had lower weight gain and feed intake(P ke(P < 0.05) and tended to have lower(P=0.062) feed conversion ratio(FCR) compared with those without access to *** performance,however,was not affected by OH nor by challenge on d 24 and *** broilers given OH had heavier gizzards(P < 0.05) compared with those without OH at d 35 but not at d 13 or *** numbers of ***(P < 0.001) and reduced numbers(P < 0.05)of Lactobacillus and Salmonellae were observed in the caecal contents of challenged broilers on d *** broilers had a lower concentration of caecal acetic acid(P < 0.01) compared with unchallenged broilers at d *** broilers given OH had lower concentrations of caecal acetic acid(P < 0.05),propionic acid(P < 0.05),and valeric acid(P < 0.01) compared with those without access to *** OH by challenge interaction on succinic acid concentration was observed on d 16(P < 0.05).Oat hulls elevated the caecal succinic acid concentration only in the unchallenged *** study indicated a positive role of OH through improved gizzard function and increased succinic acid in the gut but its role in controlling NE was not conclusive.

关键词： Necrotic enteritis Caecal microflora Performance Gizzard Oat hulls

On the Use of Adjoint-Based Sensitivity Estimates to Control Local Mesh Refinement

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Communications in Computational Physics 2010年第3期7卷 631-638页

作者： Joseph D.Frazier Peter k.Jimack robert M.kirby School of Computing University of UtahSalt Lake CityUTUSA School of Computing University of LeedsLeedsLS29JTUK

The goal of efficient and robust error control, through local mesh adaptationin the computational solution of partial differential equations, is predicated on theability to identify in an a posteriori way those localized regions whose refinement willlead to the most significant reductions in the error. The development of a posteriori errorestimation schemes and of a refinement infrastructure both facilitate this goal, howeverthey are incomplete in the sense that they do not provide an answer as to where themaximal impact of refinement may be gained or what type of refinement — elementalpartitioning (h-refinement) or polynomial enrichment (p-refinement) — will best leadto that gain. In essence, one also requires knowledge of the sensitivity of the error toboth the location and the type of refinement. In this communication we propose theuse of adjoint-based sensitivity analysis to discriminate both where and how to *** present both an adjoint-based and an algebraic perspective on defining and usingsensitivities, and then demonstrate through several one-dimensional model problemexperiments the feasibility and benefits of our approach.

关键词： Adaptivity error estimation hp-finite elements sensitivity discrete adjoint

Impact of COVID-19 on Liver Transplant Activity in the USA: Variation by Etiology and Cirrhosis Complications

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Journal of Clinical and Translational Hepatology 2023年第1期11卷 130-135页

作者： Yong-Fang kuo Paul kwo robert J Wong Ashwani k.Singal Department of Biostatistics University of Texas Medical BranchGalvestonTXUSA Division of Gastroenterology and Hepatology Veterans Affairs Palo Alto Healthcare SystemStanford University School of MedicinePalo AltoCAUSA University of South Dakota Sanford School of MedicineVermillionSDUSA Avera Transplant Institute Sioux FallsSDUSA

Background and Aims:The COVID-19 pandemic has impacted the care of patients with liver *** examined impact of COVID-19 on liver transplant(LT)activity in the ***:LT listings in the United Network for Organ Sharing(UNOS)database(April 2018–May 2021)were analyzed to examine the impact of COVID-19 pandemic on the LT activity based on etiology:hepatitis C virus(HCV),alcohol-associated liver disease(ALD),alcoholic hepatitis(AH),and nonalcoholic steatohepatitis(NASH)complications:hepatocellular carcinoma(HCC)and acute-on-chronic liver failure(ACLF)grade 2 or 3 and Model for End-Stage Liver Disease(MELD)*** regression models assessed time trend changes on a log ***:Of 23,871 recipients(8,995 in the COVID era,April 2018–February 2020),mean age 52 years,62% men,61% Caucasian,32%ALD,15%HCC,30%ACLF grades 2–3,and mean MELD score 20.5,monthly LT changes were a decrease of 3.4%for overall LTs and 22%for HCC after September 2020,and increase of 4.5%for ALD since 11/2020 and 17%since 03/2021 for ACLF grade 2–*** MELD scores increased by 0.7 and 0.36 after June 2020 for HCV and HCC ***:The COVID-19 pandemic has impacted LT activity,with a decrease of LTs especially for HCC,and an increase of LTs for ALD and severe *** are needed to reorganize cirrhosis patients to overcome the aftereffects of COVID-19 pandemic.

关键词： COVID-19 UNOS OLT Region Public policies

Resistance modulation in Ge2Sb2Te5

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Journal of Materials Science & Technology 2020年第15期47卷 171-177页

作者： Jitendra k.Behera Wei Jie Wang Xilin Zhou Shan Guan Wu Weikang Yang AShengyuan robert ESimpson ACTA Lab Singapore University of Technology and Design(SUTD)8 Somapah Road487372Singapore Jnstitute of Microelectronics A*STAR2 Fusionopolis Way138634Singapore Research Lab for Quantum Materials Singapore University of Technology and Design(SUTD)8 Somapah Road487372Singapore

Chalcogenide based phase change random access memory(PCRAM) holds great promise for high speed and large data storage *** memory is scalable,requires a low switching energy,has a high endurance,has fast switching speed,and is ***,decreasing the switching time whilst increasing the cycle endurance is a key challenge for this technology to replace dynamic random access *** we demonstrate high speed and high endurance ultrafast transient switching in the SET state of a prototypical phase change memory *** switching is modeled by electron-phonon and lattice scattering on short timescales and charge carrier excitation on long *** volatile switching in phase change materials enables the design of hybrid memory modulators and ultrafast logic circuits.

关键词： Phase change memory Transient resistance Volatile Scattering Charge carrier excitation Large endurance

Changes in forest structure, species diversity and spatial pattern following hurricane disturbance in a Piedmont North Carolina forest, USA

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Journal of Plant Ecology 2008年第1期1卷 43-57页

作者： Weimin Xi robert k.Peet Dean L.Urban Department of Biology University of North Carolina at Chapel HillChapel HillNC 29599-3280USA The Nicholas School of the Environment and Earth Sciences Duke UniversityDurhamNC 27708USA

Aims Large hurricanes have profound impacts on temperate forests,but owing to their infrequent nature these effects have rarely been examined in *** 1996,Hurricane Fran significantly damaged many long-term tree census plots in the Duke Forest on the North Carolina Piedmont,thereby providing an exceptional opportunity to examine pre-and post-hurricane forest compositional *** goal was to examine immediate,short-term(0–4 years)and longer term(;5 year)hurricane-induced structural,spatial and compositional changes in the tree population(stem d.b.h>1 cm)in the context of our detailed,long-term knowledge of the dynamics of these *** We surveyed stem damage and tree mortality in 34 long-term permanent plots(ca.70-year record;404–1012 m^(2))and 7 large mapped tree stands(ca.20-year record;5250–65000 m^(2))representing both transition-phase,even-aged pine stands and uneven-aged upland hardwood *** employed three types of damage measures to quantify stand-level damage severity:percentage of stems damaged,percentage of basal area lost and a‘stand-level damage index’.Second-order spatial analysis(Ripley’s k-function)was used to investigate patterns in tree *** findings Our study found hurricane effects on the structural attributes of Piedmont forests to be variable and *** in tree species composition,however,were *** was the major damage type for the overstory trees[diameter at breast height(d.b.h.)>10 cm]apparently due to the exposure of the crowns to high wind combined with heavy rainfall prior to and during the ***,juvenile trees and small trees(1–10 cm d.b.h.)of the understory and midstory were mainly damaged by being pinned or bent by their damaged large ***-induced tree mortality varied weakly among species,was positively correlated with pre-hurricane tree size and remained up to 2-fold higher than pre-hurricane background mortality 5 years after the ***

关键词： delayed tree mortality disturbance ecology hurricane damage d Hurricane Fran spatial point pattern analysis stand dynamics structural heterogeneity

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PDQ Biochemistry 1st

Volatile basic nitrogen measurement in digesta using a Berthelot reaction in automated Skalar instrumentation

丛书名： PDQ series

2001年

作者： Baker, R. Roy Murray, robert k.

ISBN: (纸本)9781550091502

Based on lectures given to undergraduate students in medicine, arts, and sciences, it serves both as an introduction for those coming from a non-science discipline and a refresher to those who have taken a biochemistry course before. This comprehensive text discusses many diseases and clinical applications as well as the basics of biochemistry.

关键词： Biochemistry.

来源：畅想之星图书光盘版（南... 评论

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Animal Nutrition 2020年第2期6卷 225-230页

作者： Holy k.Zanu Leanne Lisle Michael R.Bedford robert A.Swick School of Environmental and Rural Science University of New EnglandArmidaleNSW2351Australia AB Vista MarlboroughWiltshireSN84ANUnited Kingdom

The undigested nitrogenous fraction entering the hindgut of chickens is further metabolized by microbiota present producing volatile basic metabolites including amines and ammonia(NH3).Ammonia increases pH and may result in overgrowth of Clostridium perfringens further producing toxic metabolites that cause dysbacteriosis or necrotic enteritis(NE).There are few reports in chickens examining the production and concentration of nitrogenous metabolites in the hindgut.A Berthelot reaction using an automated flow,reaction and spectrophotometric instrumentation to detect volatile basic nitrogen in the form of NH3 from cecal contents was carried *** the Berthelot reaction,NH3 in the sample is chlorinated to monochloramine using dichloroisocyanuric acid that then reacts with salicylate to form 5-aminosalicylate which is stable under alkaline conditions(pH 12 to 13).After oxidation and oxidative coupling,a coloured complex is formed that can be measured at 660 *** contents were collected and pooled from 2 birds per pen with 48 pens total in each of 3 experiments and stored in sealed containers at-20℃prior to *** 1 compared samples collected from birds fed either no meat and bone meal(MBM)or 6%MBM from d 0 to 14,and samples collected from birds fed either no MBM or 5%MBM from d 14 to *** birds were challenged with Eimeria on d 9 and *** on d 14 and *** 2 compared cecal contents from birds fed either 0.5%or 0.9%calcium(Ca),and Exp.3 compared unchallenged with NE challe nge on d 16 and *** demonstrated an increase(Pkalar instrumentation equipment is suitable to measure the concentration of volatile nitrogen as NH3 in cecal contents of chickens.

关键词： Ammonia Berthelot method Broiler Cecal content Volatile basic nitrogen