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Structural,electronic,optical,and magnetic properties of Co-doped Cu2O

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Chinese Physics B 2017年第2期26卷 387-391页

作者： I Djabri T Rezkallah f Chemam Laboratoire de la Physique Appliquee et Theorique Departement des Sciences de la matiere Universite Laarbi tebessi tebessa Algeri

We investigate the magnetic properties of Co-doped Cu_2O. We studied first the electronic and structural properties of Cu_2O using the optimization of the lattice constant which is 4.18 . The calculated gap is found between 0.825 eV and1.5 eV, these values are in good agreement with the experimental results. The Co atoms are inserted in Cu_2O by means of the density functional theory（DfT） using LSDA, LSDA ＋U, and LSDA ＋ MBJ approximations in the WIEN2 k code, based on the supercell model by setting up 12, 24, and 48 atoms in（1×1 × 2）,（1 × 2 × 2）, and（2 × 2×2） supercells respectively with one or two copper atoms being replaced by cobalt atoms. The energy difference between the ferromagnetic and antiferromagnetic coupling of the spins located on the substitute Co has been calculated in order to obtain better insight into the magnetic exchange coupling for this particular compound. The studied compound exhibits stable integer magnetic moments of 2 μBand 4 μBwhen it is doped with 2 atoms of Co. Optical properties have also been worked out. The results obtained in this study demonstrate the importance of the magnetic effect in Cu_2O.

关键词： Cu2O electronic structure magnetic properties optical properties

A CRACK CLOSURE MODEL fOR BRITTLE ROCK SUBJECTED TO COMPRESSIVE-SHEAR LOADING

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中国有色金属学会会刊：英文版 1999年第2期9卷 223-228页

作者： Chen, f Sun, ZQ Xu, JC Cent S Univ Technol Opening Lab Mech Changsha 410083 Peoples R China

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关键词： crack closurecompressiveshear loadingstress intensity factor

Analyzing the H19-and T65-epitopes in 38 kd phosphory-lated protein of Marek's disease viruses and comparing chicken immunological reactions to viruses point-mutated in the epitopes

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Science China(Life Sciences) 2004年第1期47卷 82-91页

作者： Lee Lucy f Avian Disease and Oncology Laboratory East Lansing Ml 48823 USA

DNA sequencing analysis in 38 kd phosphorylated protein (pp38) ORf of Marek's disease viruses (MDV) indicated that all tested 10 virulent strains with different pathotypes had 'A' at base #320 and glutamine at aa#107 while reacted with monoclonal antibody (Mab) H19 in indirect fluorescence antibody test (IfA). However, vaccine strain CVI988 had 'G' at base#320 and arginine at aa#107 instead, when it was negative in IfA with Mab H19. Some strains were also reactive with Mab T65 in IfA while there was 'G' at base #326 and glycine at aa#109, but the other strains, which had 'A' at base #326 and glutamic acid at aa#109, did not react with Mab T65. By comparison of CVI988 to its point mutants CVI/rpp38(AG) and CVI/rpp38(AA) with 1 or 2 base(s) changes at bases #320 and /or #326 of pp38 gene for their reactivity with Mab H19 and T65, it was confirmed that the glutamine at aa#107 and glycine at aa#109 were critical to epitopes H19 and T65 respectively. Immuno-reactions to MDV were compared in SPf chickens inoculated with cloned CVI988 and its mutant CVI/rpp38(AG). It was found that antibody responses to MDV in chickens inoculated with CVI/rpp38(AG) were delayed and significantly lower than that in chickens inoculated with the native CVI988. By differential comparison of antibody titers to different antigens, a third epitope specific to CVI988 and dependent on arginine at aa#107 was suggested to be responsible for the big difference in antibody responses induced by native CVI988 and its mutant.

关键词： Marek's disease virus, pp38 gene, point mutant, epitopes, antibody responses.

On the intraspecific variability in basal metabolism and the food habits hypothesis in birds

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Current Zoology 2010年第6期56卷 759-766页

作者： f. BOZINOVIC P. SABAT Center for Advanced Studies in Ecology and Biodiversity LINC-Globaland Departamento de EcologíaFacultad de Ciencias BiológicasPontificia Universidad Católica de Chile Center for Advanced Studies in Ecology and Biodiversity LINC-Globaland Departamento de EcologíaFacultad de Ciencias BiológicasPontificia Universidad Catolica de Chile Departamento de Ciencias Ecológicas Facultad de CienciasUniversidad de Chile

The food habits hypothesis （fHH） stands as one of the most striking and often-cited interspecific patterns to emerge from comparative studies of endothermic energetics. The fHH identifies three components of diet that potentially produce variability in mass-independent BMR, i.e. food quality, food availability, and food predictability or environmental productivity. The hypothesis predicts that species with diets of low energy content and/or low digestibility should evolve low mass-independent BMRs. The effects of food habits on BMR have been widely investigated at the interspecific level, but the variation between individuals and populations has been largely ignored. Our focus is to compare predictions derived from interspecific studies with data collected from within-species studies to explore the mechanisms and functional significance of adaptive responses predicted by the food-habits hypothesis among birds. We conclude that if BMR is correlated with daily energy expenditure, then organisms that can lower BMR will reduce daily energy expenditure and hence, food requirements. Birds that lower BMR in stressful environments may increase survival. Nevertheless, the mechanism （s） by which birds eating a low quality diet reduce BMR and whether lower BMR affects fitness remain to be determined [Current Zoology 56 （6）： 759-766, 2010].

关键词： Intraspecific comparisons Avian energetics food habits hypothesis Diet Basal metabolic rate

Seasonal size-segregated PM10 and PAH concentrations in a rural area of sugarcane agriculture versus a coastal urban area in Southeastern florida, USA

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Particuology 2016年第5期14卷 52-59页

作者： Orhan Sevimoglu Wolfgang f. Rogge Department of Civil and Environmental Engineering Florida International University 10555 W. Flagier Street Miami FL 33174 USA School of Engineering and Sierra Nevada Research Institute University of California at Merced 5200 North Lake Road Merced CA 95343 USA

Airborne particulate matter （PM） is of health and environmental concern not only in highly urbanized areas, but also in rural areas that are used for intensive agricultural purposes, In this study, PM size- segregated samples were collected simultaneously for 12 months in a small town （Belle Glade, florida）, which is the center of a vast sugarcane growing area and at Delray Beach, a coastal city in Palm Beach County, florida. During the winter sampling period, when sugarcane foliage is burned just before harvest- ing to reduce the amount of plant matter to be handled, PM10 levels were 50% or higher than otherwise measured, indicating that sugarcane harvesting and processing is a major local source for PM10. for the rest of the year, PM10 levels at both sites are similar, suggesting that ambient PM levels at both sites are impacted by the major urban centers in Southern florida. During late July and early August, the PM10 levels at both sites were substantially elevated and revealed the typical red-brownish color of Saharan dust. This has been reported to occur frequently with suitable meteorological conditions over the Atlantic Ocean coupled with a Sahara dust storm event. During the sugarcane harvesting season at Belle Glade, the concentrations of PAHs associated with PM10 were up to 15 times higher than those measured during the summer growing season, indicating a substantially higher exposure of the rural population to these often mutagenic and carcinogenic compounds.

关键词： Size segregated ambient particles PM10 PAHs Biomass burning Rural versus urban Saharan dust

Engineering vibration monitoring by GPS:long duration records

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Earthquake Engineering and Engineering Vibration 2009年第3期8卷 459-467页

作者： f.Casciati C.fuggini Department of Structural Mechanics University of PaviaItaly

Monitoring the performance of any structure requires real-time measurements of the change of position of critical points. Different techniques can be used for this purpose, each one offering advantages and disadvantages. The technique based on satellite positioning systems （GPS, GLONASS and the future GALILEO） seems to be very promising at least for long period structures. The GPS in particular provides sampling rates that are able to track dynamic displacements with high accuracy. Its service ability is independent of atmospheric conditions, temperature variations and visibility of the monitored object. This paper investigates the reliability and accuracy of the measurements of dual frequency GPS receivers. A linear electromagnetic motor moves an object along a given direction. The changes of position are compared witb their estimates as recorded by a GPS receiver, whose antenna is located on the reference object. The comparison is based on sufficiently long records.

关键词： infrastructure monitoring global positioning system (GPS) delay positioning errors multi-path error signal geometric dilution of precision linear motor amplitudes power spectral densities

Concept of Intelligent Mechanical Design for Autonomous Mobile Robots

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Journal of Bionic Engineering 2007年第4期4卷 217-226页

作者： Amir A. f Nassiraei Kazuo Ishii Kyushu Institute of Technology Kitakyushu Fukuoka 808-0196 Japan

The concept of Intelligent Mechanical Design （IMD） is presented to show how a mechanical structure can be designed to affect robot controllability, simplification and task performance. Exploring this concept produces landmarks in the territory of mechanical robot design in the form of seven design principles. The design principles, which we call the Mecha-Telligence Principles （MTP）, provide guidance on how to design mechanics for autonomous mobile robots. These principles guide us to ask the right questions when investigating issues concerning self-controllable, reliable, feasible, and compatible mechanics for autonomous mobile robots. To show how MTP can be applied in the design process we propose a novel methodology, named as Mecha-Telligence Methodology （MTM）. Mechanical design by the proposed methodology is based on preference classification of the robot specification described by interaction of the robot with its environment and the physical parameters of the robot mechatronics. After defining new terms, we investigate the feasibility of the proposed methodology to the mechanical design of an autonomous mobile sewer inspection robot. In this industrial project we show how a passive-active intelligent moving mechanism can be designed using the MTM and employed in the field.

关键词： mechanical design intelligent autonomous robot mobile robot

Increased salt sensitivity induced by sensory denervation: role of superoxide

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Acta Pharmacologica Sinica 2004年第12期25卷 60-66页

作者： Alex f CHEN,Donna H WANG Department of Medicine and Pharmacology & Toxicology Michigan State University East Lansing MI 48824 USA Department of Medicine and Pharmacology & Toxicology Michigan State University East Lansing MI 48824 USA

AIM: To test the hypothesis that production of superoxide in mesenteric resistance arteries is increased and con- tributes to the development of hypertension induced by sensory denervation plus high salt intake. METHODS: Newborn Wistar rats were given capsaicin 50 mg/kg sc on the 1st and 2nd d of life. After weaning, male rats were grouped as follows and treated for 3 weeks with: capsaicin pretreatment plus normal sodium diet (0.5 %, CAP-NS), CAP plus high sodium diet (4 %, CAP-HS), control plus NS (CON-NS), or CON-HS. Both tail-cuff systolic blood pressure and mean arterial pressure (MAP) were measured in each of the groups. Western blot analysis was used for measurement of manganese superoxide dismutase (MnSOD) and endothelial nitric oxide synthase (eNOS) in the mesenteric resistance arteries. Lucigenin chemiluminescence assay was used for superoxide production in the mesenteric resistance arteries. The Griess method was used for measurement of nitrite/nitrate levels in plasma. RESULTS: Both tail-cuff pressure and MAP were higher in CAP-HS compared with CAP-NS, CON-HS, and CON- NS rats (Pfferent among 4 groups. Acute iv administration of tempol, a membrane-permeable superoxide scavenger, de- creased MAP in both CAP-HS and CON-HS when compared with their respective controls. However, the de- creases of MAP between these two groups were not different. Chronic treatment with tempol failed to prevent the development of hypertension in CAP-HS rats. Superoxideproduction in the mesenteric resistance arteries was increased in CAP-HS compared with CAP-NS, CON-HS, and CON-NS (Pf mesenteric superoxideproduction in CAP-HS rats. CONCLUSIONS: Regardless of increased vascular MnSOD levels, salt

关键词： superoxides tempol afferent neurons capsaicin denervation dietary sodium chloride nitric oxide

Battery prognostics and health management for electric vehicles under industry 4.0

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Journal of Energy Chemistry 2023年第9期84卷 30-33页

作者： Jingyuan Zhao Andrew f.Burke Institute of Transportation Studies University of California DavisDavisCA 95616USA

Transportation electrification is essential for decarbonizing transport. Currently, lithium-ion batteries are the primary power source for electric vehicles (EVs). However, there is still a significant journey ahead before EVs can establish themselves as the dominant force in the global automotive market. Concerns such as range anxiety, battery aging, and safety issues remain significant challenges.

关键词： Lithium-ion battery Prognostics and health management Machine learning Cloud Artificial intelligence Digital twins Lifelong learning