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Deposition processes and properties of coatings on steel fasteners——A review

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Friction 2019年第5期7卷 389-416页

作者： Ping Ping CHUNG james WANG Yvonne DURANDeT Department of Mechanical and Product Design engineering Faculty of Science Engineering and Technology Swinburne University of Technology

Mechanical fastening is widely used in joining metals, particularly in automotive, aerospace, building and construction industries. However, the main concern on mechanical fastening is the issue of corrosion. An effective way to prolong the service life of steel fasteners is to apply protective coatings onto these components. This paper reviews and compares a few common coating deposition techniques, i.e., electroplating, hot-dip galvanizing, ion vapour deposition and mechanical plating, in terms of their characteristics. Compositional and microstructural properties including morphology and porosity, corrosion resistance performance and frictional performance of the coatings formed by each process are discussed in details. Hydrogen embrittlement, a premature failure often occurred on high strength steel fasteners, is also reviewed. The key results of recent studies of various metallic coatings on fasteners are presented to provide a fundamental understanding of the evolving topics, and the research gaps have been identified for further investigation.

关键词： zinc coating steel fasteners frictional characteristics corrosion performance mechanical plating electroplating

Moose at their bioclimatic edge alter their behavior based on weather, landscape, and predators

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Current Zoology 2018年第4期64卷 419-432页

作者： Mark A. DITMeR Ron A. MOeN Steve K. WINDeLS james D. FOReSTeR Thomas e, NeSS Tara R. HARRIS Conservation Department Minnesota Zoo 13000 Zoo Boulevard Apple Valley MN 55124 USA Department of Fisheries Wildlife and Conservation Biology University of Minnesota 2003 Upper Buford Circle Ste 135 St Paul MN 55108 USA Natural Resources Research Institute and Department of Biology University of Minnesota Duluth 5013 Miller Trunk Highway Duluth MN 55811 USA Voyageurs National Park 360 Hwy 11 E International Falls MN 56649 USA

Populations inhabiting the bioclimatic edges of a species＇ geographic range face an increasing amount of stress from alterations to their environment associated with climate change. Moose Alces alces are large-bodied ungulates that are sensitive to heat stress and have exhibited population declines and range contractions along their southern geographic extent. Using a hidden Markov model to analyze movement and accelerometer data, we assigned behaviors （rest, forage, or travel） to all locations of global positioning system-collared moose （n = 13, moose-years = 19） living near the southern edge of the species＇ range in and around Voyageurs National Park, MN, USA. We assessed how moose behavior changed relative to weather, landscape, and the presence of predators. Moose sig- nificantly reduced travel and increased resting behaviors at ambient temperatures as low as 15~C and 24~C during the spring and summer, respectively. In general, moose behavior changed season- ally in association with distance to lakes and ponds. Moose used wetlands for travel throughout the year, rested in conifer forests, and foraged in shrublands. The influence of wolves Canis lupus varied among individual moose and season, but the largest influence was a reduction in travel during spring when near a wolf home range core, primarily by pregnant females. Our analysis goes beyond habitat selection to capture how moose alter their activities based on their environment. Our findings, along with climate change forecasts, suggest that moose in this area will be required to further alter their activity patterns and space use in order to find sufficient forage and avoid heat stress.

关键词： Alces alces climate change heat stress moose temperature wolves

Selective toxicity of hydroxyl-rich carbon nanodots for cancer research

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Nano Research 2018年第4期11卷 2204-2216页

作者： Tak H. Kim Joseph P. Sirdaarta Qian Zhang ehsan eftekhari james St. John Derek Kennedy Ian e. Cock Qin Li Queensland Micro and Nano Technology Center & School of engineering Griffith University 170 Kessels Rd Nathan OLD 4111 Australia Australian Rivers Institute & School of Natural Sciences Griffith University 170 Kessels Rd Nathan QLD 4111 Australia Griffith Institute for Drug Discovery Gfiffith University 46 Don Young Rd Nathan QLD 4111 Australia Menzies Health Institute Queensland Griffith University Parkland Drive Southport QLD 4222 Australia

The toxicity of nanoparticles in a biological system is an integration of effects arising from surface functionali~ particle size, ionic dissolution, etc. This complexity suggests that generalization of a material＇s toxicity may be inappropriate. Moreover, from a medicinal point of view, toxicity can be used for treatment of malignant cells, such as cancer. In this stud~ highly biocompatible carbon nanodots （gCDs） were synthesized by reacting citric acid and urea in glycerol, which resulted in abundant hydroxyl functional groups on the particle surface. gCDs show excitation-dependent photoluminescence but with bright green to yellow emission. Importantly, a series of toxicity assessments showed that as-synthesized gCDs possessed exceptional biocompatibilities to various biological entities including 18 bacteria species, Petunia axillaris seedlings, and Artemia franciscana nauplii. Furthermore, the particles were shown to have low to no toxic effects on human embryonic kidney （HeK-293）, breast （MCF-7）, and oral squamous （CAL-27） carcinoma cell lines. Of particular interest, the gCDs displayed antiproliferative activities against ovarian choriocarcinoma cells （JAr/Jeg-3 cell lines）, which may be further explored for cancer drug discovery.

关键词： carbon nanodots nanotoxicity fluorescence choriocarcinoma cells thioredoxin reductase

Direct measurement of the break-out ^(19)F(p,γ)^(20)Ne reaction in the China Jinping underground laboratory(CJPL)

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Nuclear Science and Techniques 2024年第8期35卷 142-152页

作者： Yin‑Ji Chen Hao Zhang Li‑Yong Zhang Jian‑Jun He Richard james deBoer Michael Wiescher Alexander Heger David Kahl Jun Su Daniel Odell Xin‑Yue Li Jian‑Guo Wang Long Zhang Fu‑Qiang Cao Zhi‑Cheng Zhang Xin‑Zhi Jiang Luo‑Huan Wang Zi‑Ming Li Lu‑Yang Song Liang‑Ting Sun Qi Wu Jia‑Qing Li Bao‑Qun Cui Li‑Hua Chen Rui‑Gang Ma er‑Tao Li Gang Lian Yao‑De Sheng Zhi‑Hong Li Bing Guo Wei‑Ping Liu Key Laboratory of Beam Technology of the Ministry of education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Department of Physics and Astronomy The Joint Institute for Nuclear AstrophysicsUniversity of Notre DameNotre DameIN 46556USA School of Physics and Astronomy Monash UniversityClaytonVIC 3800Australia Facility for Rare Isotope Beams Michigan State UniversityEast LansingMI 48824USA Institute of Nuclear and Particle Physics and Department of Physics and Astronomy Ohio UniversityAthensOH 45701USA Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China China Institute of Atomic energy Beijing 102413China College of Physics and Optoelectronic engineering Shenzhen UniversityShenzhen 518060China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China College of Science Southern University of Science and TechnologyShenzhen 518055China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China Key Laboratory of Nuclear Physics and Ion‑Beam Application(MOe) Institute of Modern PhysicsFudan UniversityShanghai 200433China School of Mathematics and Physics Handan UniversityHandan 056005China

Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in *** one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle was thought to be the source of the calcium observed in these oldest ***,according to the stellar modeling,a nearly tenfold increase in the thermonuclear rate ratio of the break-out ^(19)F(p,γ)^(20) Ne reaction with respect to the competing ^(19)F(p,α)^(16) O back-processing reaction is required to reproduce the observed calcium *** performed a direct measurement of this break-out reaction at the China Jinping underground *** measurement was performed down to the low-energy limit of e_(c.m.)=186 keV in the center-of-mass *** key resonance was observed at 225.2 keV for the first *** a temperature of approximately 0.1 GK,this new resonance enhanced the thermonuclear ^(19)F(p,γ)^(20) Ne rate by up to a factor of≈7.4,compared with the previously recommended NACRe *** is of particular interest to the study of the evolution of the first stars and implies a stronger breakdown in their“warm”CNO cycle through the ^(19)F(p,γ)^(20) Ne reaction than previously *** break-out resulted in the production of the calcium observed in the oldest stars,enhancing our understanding of the evolution of the first stars.

关键词： Nuclear astrophysics First stars Abundance of calcium Reaction cross section Reaction rate China Jinping underground laboratory(CJPL) JUNA

Number of COVID-19 cases required in a population to detect SARS-CoV-2 RNA in wastewater in the province of Alberta, Canada:Sensitivity assessment

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Journal of environmental Sciences 2023年第3期125卷 843-850页

作者： Qiaozhi Li Bonita e.Lee Tiejun Gao Yuanyuan Qiu erik ellehoj Jiaao Yu Mathew Diggle Graham Tipples Rasha Maal-Bared Deena Hinshaw Christopher Sikora Nicholas J.Ashbolt james Talbot Steve e.Hrudey Xiaoli Pang School of Public Health University of AlbertaEdmontonAB T6G 2R3Canada Department of Pediatrics University of AlbertaEdmontonAB T6G 1C9Canada Department of Laboratory Medicine and Pathology University of AlbertaEdmontonAB T6G 2B7Canada University of Alberta Central Receiving EdmontonAlbertaT6G 2R3Canada Provincial Laboratory for Public Health EdmontonAlbertaCanada ePCOR EdmontonAB T5H 0E8Canada Department of Medicine University of AlbertaEdmontonAB T6G 2G3Canada Faculty of Science and engineering Southern Cross UniversityEast Lismore NSW 2480Australia

With a unique and large size of testing results of 1,842 samples collected from 12 wastewater treatment plants (WWTP) for 14 months through from low to high prevalence of COVID-19,the sensitivity of RT-qPCR detection of SARS-CoV-2 RNA in wastewater that correspond to the communities was computed by using Probit *** study determined the number of new COVID-19 cases per 100,000 population required to detect SARS-CoV-2RNA in wastewater at defined probabilities and provided an evidence-based framework of wastewater-based epidemiology surveillance (WBe).Input data were positive and negative test results of SARS-CoV-2 RNA in wastewater samples and the corresponding new COVID-19 case rates per 100,000 population served by each *** analyses determined that RT-qPCR-based SARS-CoV-2 RNA detection threshold at 50%,80%and 99%probability required a median of 8 (range:4-19),18 (9-43),and 38 (17-97) of new COVID-19 cases/100,000,***,the positive detection rate at 50%,80%and 99%probability were 0.01%,0.02%,and 0.04%averagely for new cases in the *** study improves understanding of the performance of WBe SARS-CoV-2 RNA detection using the large datasets and prolonged study *** COVID-19 burden at a community level that would result in a positive detection of SARS-CoV-2 in wastewater is critical to support WBe application as a supplementary warning/monitoring system for COVID-19 prevention and control.

关键词： SARS-CoV-2 COVID-19 cases Wastewater Probit analysis Probability Detection sensitivity

Recent trends in liver transplantation for alcoholic liver disease in the United States

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World Journal of Hepatology 2017年第36期9卷 1315-1321页

作者： Catherine e Kling james D Perkins Robert L Carithers Dennis M Donovan Lena Sibulesky Division of Transplant Surgery Department of Surgery University of Washington Division of Gastroenterology and Hepatology Department of Medicine University of Washington Department of Psychiatry and Behavioral Sciences University of Washington

AIM To examine temporal changes in the indications for liver transplantation(LT) and characteristics of patients transplanted for alcoholic liver disease(ALD).MeTHODS We performed a retrospective cohort analysis of trends in the indication for LT using the United Network for Organ Sharing(UNOS) database between 2002 and 2015. Patients were grouped by etiology of the liver disease and characteristics were compared using χ~2 and t-tests. Time series analysis was used identifying any year with a significant change in the number of transplants per year for ALD, and before and after eras were modeled using a general linear model. Subgroup analysis of recipients with ALD was performed by age group, gender, UNOS region and etiology(alcoholic cirrhosis, alcoholic hepatitis and hepatitis C-alcoholic cirrhosis dual listing).ReSULTS Of 74216 liver transplant recipients, ALD(n = 9400, 12.7%) was the third leading indication for transplant after hepatitis C and hepatocellular carcinoma. Transplants for ALD, increased from 12.8%(553) in 2002 to 16.5%(1020) in 2015. Time series analysis indicated a significant increase in the number of transplants per year for ALD in 2013(P = 0.03). There were a stable number of transplants per year between 2002 and 2012(linear coefficient 3, 95%CI:-4.6, 11.2) an increase of 177 per year between 2013 and 2015(95%CI: 119, 234). This increase was significant for all age groups except those 71-83 years old, was observed for both genders, and was incompletely explained by a decrease in transplants for hepatitis C and ALD dual listing. All UNOS regions except region 9 saw an increase in the mean number of transplants per year when comparing eras, and this increase was significant in regions 2, 3, 4, 5, 6, 8, 10 and *** There has been a dramatic increase in the number of transplants for ALD starting in 2013.

关键词： Alcoholic liver disease Liver transplantation Cirrhosis epidemiology Hepatitis C

Topology optimization based on reduction methods with applications to multiscale design and additive manufacturing

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Frontiers of Mechanical engineering 2020年第1期15卷 151-165页

作者： emmanuel TROMMe Atsushi KAWAMOTO james KGUeST Department of Civil engineering Johns Hopkins UniversityBaltimoreMD 21218USA Toyota Central R&D Labs. Inc.NagakuteAichi 480-1192Japan

Advanced manufacturing processes such as additive manufacturing offer now the capability to control material placement at unprecedented length scales and thereby dramatically open up the design *** includes the considerations of new component topologies as well as the architecture of material within a topology offering new paths to creating lighter and more efficient *** optimization is an ideal tool for navigating this multiscale design problem and leveraging the capabilities of advanced manufacturing ***,the resulting design problem is computationally challenging as very fine discretizations are needed to capture all micro-structural *** this paper,a method based on reduction techniques is proposed to perform efficiently topology optimization at multiple *** method solves the design problem without length scale separation,i.e.,without iterating between the two ***,connectivity between space-varying micro-structures is naturally *** design problems for various types of micro-structural periodicity are performed to illustrate the method,including applications to infill patterns in additive manufacturing.

关键词： multiscale topology optimization micro-structure additive manufacturing reduction techniques substructuring static condensation super-element

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 er than 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

ON SeRVICeS ReSeARCH AND eDUCATION

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Journal of Systems Science and Systems engineering 2006年第3期15卷 257-283页

作者： james M.TIeN Daniel BeRG Department of Decision Sciences and engineering Systems Rensselaer Polytechnic Institute

The importance of the services sector can not be overstated; it employs 82.1 percent of the U. S. workforce and 69 percent of graduates from an example technological university. Yet, university research and education have not followed suit. Clearly, services research and education deserve our critical attention and support since services - and services innovation - serve as an indispensable engine for global economic growth. The theme of this paper is that we can and should build services research and education on what has occurred in manufacturing research （especially in regard to customization and intellectual property） and education; indeed, services and manufactured goods become indistinguishable as they are jointly co-produced in real-time. Fortunately, inasmuch as manufacturing concepts, methodologies and technologies have been developed and refined over a long period of time （i.e., since the 1800s）, the complementary set of concepts, methodologies and technologies for services are more obvious. However, while new technologies （e.g., the Internet） and globalization trends have served to enable, if not facilitate, services innovation, the same technologies （e.g., the Internet） and 21st Century realities （e.g., terrorism） are making services innovation a far more complex problem and, in fact, may be undermining previous innovations in both services and manufacturing. Finally, there is a need to define a ＂knowledge-adjusted＂ GDP metric that can more adequately measure the growing knowledge economy, one driven by intangible ideas and services innovation.

关键词： Services manufacturing customization innovation education intellectual property