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chinese Physics B 2013年第7期22卷 96-103页

作者： m. J. Park S. m. Lee J. W. Son o. m. Kwon E. J. cha School of Electr.cal Engineering Chungbuk National University School of Electronic Engineering Daegu University Division of IT-convergence Daegu Gyeongbuk Institute of Science & Technology Department of Biomedical Engineering School of MedicineChungbuk National University

We study the leader-following consensus stability and stabilization of networked multi-teleoperator systems with interval time-varying communication delays. With the constr.ction of a suitable Lyapunov–Krasovskii functional and the utilization of the r.cipr.cally convex approach, novel delay-dependent consensus stability and stabilization conditions for the systems are established in terms of linear matrix inequalities, which can easily be solved by various effective optimization algorithms. one illustrative example is given to illustrate the effectiveness of the proposed methods.

关键词： multi-teleoperator systems interval time-varying delay leader–following consensus problem Lyapunov method

calcium phosphate conversion technique:A versatile route to develop corrosion resistant hydroxyapatite coating over mg/mg alloys based implants

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Journal of magnesium and Alloys 2022年第7期10卷 1821-1845页

作者： G.S.Hikku c.Arthi r.B.Jeen robert K.Jeyasubramanian r.murugesan medical Bionanotechnology Faculty of Allied Health SciencesChettinad Hospital and Research InstituteChettinad Academy of Research and EducationKelambakkamTamilnadu 603103India Nanobiotechnology Amirta Centre for Nanoscience and Molecular MedicineAmirtha Vishwa VidhyapeethamErnakulamKerala 682041India Department of mechanical Engineering AAA College of Engineering and TechnologySivakasiTamilnadu 626005India Department of chemistry Mepco Schlenk Engineering CollegeSivakasiTamilnadu 626005India Karpaga Vinayaga Institute of medical Sciences and research centre PalayanoorTamilnadu 603308India

Globally,vast research interest is emerging towards the development of biodegradable orthopedic implants as it overcomes the toxicity exerted by non-degradable implants when fixed in the human body for a longer *** this context,magnesium(mg)plays a major role in the production of biodegradable implants owing to their.char.cteristic degradation nature under the influence of body ***,mg is one of the essential nutrients required to perform various metabolic activities by the human cells,and therefore,the degraded mg products will be readily absorbed by the nearby ***,the higher.corrosion rate in the biological environment is the primary downside of using mg implants that liberate H2gas resulting in the formation of ***,in certain cases,mg undergoes complete degradation before the healing of damaged bone tissue and cannot serve the purpose of providing mechanical ***,many studies have been focused on the development of different strategies to improve the corrosion-resistant behavior of mg according to the *** this regard,the present review focused on the limitations of using pure mg and mg alloys for the fabr.cation of medical implants and how the calcium phosphate conversion coating alters the corrosive tendency through the formation of hydroxyapatite protective films for enhanced performance in medical implant applications.

关键词： Biodegradable implants magnesium controlled corrosion Alloying Hydroxyapatite calcium phosphate conversion coating

ImProVING THE mEcHANIcAL ProPErTIES oF coPPEr ALLoYS BY THErmo-mEcHANIcAL Pr.cESSING

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Acta metallurgica Sinica(English Letters) 2004年第2期17卷 111-117页

作者： m.c.Somani L.P.Karjalainen Department of mechanical Engineering University of Oulu90014 OuluFinlandDepartment of Mechanical EngineeringUniversity of Oulu90014 OuluFinland

Systematic physical simulation of thermo-mechanical pr.cessing routes has been ap-plied on a Gleeble 1500 simulator to four.copper alloys (mass %) cu-0.57co-0.32Si,cu-0.55cr-0.065P, cu-0.22Zr-0.035Si and cu-1.01Ni-0.43Si aimed at clarifying theinfluences of pr.cessing conditions on their final properties, strength and electr.calconductivity. Flow curves were determined over wide temperature and strain rateranges. Hardness was used as a measure of the strength level achieved. High hard-ness was obtained as using equal amounts (strains 0.5) of cold deformation beforeand after the pr.cipitation annealing stage. The maximum values achieved for thecu-co-Si, cu-cr-P, cu-Zr-Si and cu-Ni-Si alloys were 190, 165, 178 and 193 HV5,respectively. A thermo-mechanical schedule involving the hot deformation-ageing-colddeformation stages showed even better results for the cu-Zr-Si alloy. consequently,the pr.cessing routes were designed based on simulation test results and wires of 5 and2mm in diameters have been successfully pr.cessed in the industrial scale.

关键词： copper allys thermo-mechanical pr.cessing ageing strength flow stress hardness

chinese seventh Arctic scientific expedition

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Acta oceanologica Sinica 2017年第3期36卷 115-116页

作者： LIU Na KoNG Bin LIN lina HE Yan LIU Yanguang LIN Longshan ZHANG Tao cHEN Jianfang The First Institute of oceanography State Oceanic Administration Qingdao 266061 China college of marine and Earth Sciences Tongji University Shanghai 200092 China Third Institute of oceanography State Oceanic Administration Xiamen 361005 China Second Institute of oceanography State Oceanic Administration Hangzhou 310012 China

chinese seventh Arctic scientific expedition began from Shanghai on July 11,2016,journeying through the Bering Sea—chukchi Sea—canada Basin area—submarine plateau of the chukchi Sea—high latitudes Arctic ocean—mendeleyev ridge and covered more than 13 000 n mile in 78 *** distance travelled in floating ice area is more than 2 800 n mile and the northernmost point of the

关键词： Arctic submarine floating plateau canada latitude covered meteorology completed subsurface

Seasonal changes in sperm parameters, testicular histology and circulating levels of reproductive hormones in the male Afr.can straw-colored fruit bat (Eidolon helvum)

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Asian pacific Journal of reproduction 2020年第4期9卷 197-203页

作者： clifford N Abiaezute chike F oguejiofor Innocent c Nwaogu Ikechukwu r obidike Udensi m Igwebuike Department of Veterinary Anatomy Faculty of Veterinary MedicineUniversity of NigeriaNsukka 410001Nigeria Department of Veterinary obstetr.cs and reproductive Diseases Faculty of Veterinary MedicineUniversity of NigeriaNsukka 410001Nigeria Department of Veterinary Physiology and Pharmacology Faculty of Veterinary MedicineUniversity of NigeriaNsukka 410001Nigeria

objective: To investigate seasonal changes in some reproductive char.cteristics of the male Afr.can straw-colored fruit bat [Eidolon (E.) helvum] in a tropical rain forest area of South-East ***: Spermatozoal char.cteristics in the testes and cauda epididymides, testicular histology, and the circulating levels of the reproductive hormones, testosterone, follicle stimulating hormone and luteinizing hormone were evaluated in male bats captured in late January (peak dry season), late may (early rainy season) and late September (late rainy season) of 2019. The bats were captured in obiagu community in Enugu State, South-East Nigeria. Data were analyzed with analysis of variance. results: There were high serum concentrations of testosterone in early and late rainy season and of luteinizing hormone in early rainy season, but the concentrations of both hormones were low during peak dry season. These hormonal changes corresponded with the testicular seminiferous and spermatogenic activities and testicular and epididymal sperm concentrations, which were also maximal during early and late rainy season but minimal during peak dry season. Epididymal sperm motility and vitality were also high in early and late rainy season but low in peak dry season, while sperm morphological abnormalities were low in early and late rainy season but elevated in peak dry season. There was histological evidence that spermatogenesis did not cease completely during testis regression, but continued at a reduced rate during the dry season. conclusions: The findings do not support concurrent epididymal sperm storage with testis regression in E. helvum. Altogether, these indicate that seasonal changes significantly alter sperm char.cteristics, testicular histology and circulating levels of reproductive hormones in E. helvum within the study area.

关键词： Eidolon helvum Spermatozoa reproductive char.cteristics Seasonal changes

Adding vortexing to the maki technique provides no benefit for the diagnosis of catheter.colonization or.catheter-related bacteremia

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World Journal of critical care medicine 2024年第1期13卷 58-64页

作者： Leonardo Lorente maria Lecuona Fernandez Adriana González-mesa Judith oliveras-roura cristina rosado Pablo cabrera Emma casal Alejandro Jiménez maría Luisa mora Ana madueño Intensive care Unit Hospital Universitario de CanariasLa Laguna 38320Spain microbiology and Infection control Service Hospital Universitario de CanariasLa Laguna 38320Spain research Unit Hospital Universitario de CanariasLa Laguna 38320Spain

BAcKGroUND A previous study compared vortexing and maki techniques for the diagnosis of catheter-related bloodstream infection(crBSI),and concluded that vortexing was not superior to maki *** To determine whether the combined use of vortexing and maki techniques provides profitability versus the maki technique for the diagnosis of catheter tip colonization(cTc)and *** observational and prospective study carried out in an Intensive care *** with suspected catheter-related infection(crI)and with one central venous catheter for at least 7 days were *** area under the curve(AUc)of the maki technique,the vortexing technique and the combination of both techniques for the diagnosis of cTc and crBSI were *** We included 136 episodes of suspected *** found 21 cases of cTc of which 10 were also crBSI *** the 21 cTc episodes,18(85.7%)were diagnosed by maki technique and vortexing technique,3(14.3%)only by the technique of maki,and none only by technique of *** the 10 crBSI episodes,9(90.0%)were diagnosed by the techniques of maki and vortexing,1(10.0%)was diagnosed only by the technique of maki,and none only by the technique of *** no found differences in the comparison of AUc between the technique of maki and the combination of maki and vortexing techniques for the diagnosis of cTc(P=0.99)and crBSI(P=0.99).coNcLUSIoN The novel finding of our study was that the combined use of vortexing and maki techniques did not provide profitability to the technique of maki alone to crBSI diagnosis of.

关键词： Vortexing maki Bloodstream infection colonization

Application of thermally stimulated acoustic emission method to assess the thermal resistance and related properties of coals

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International Journal of mining Science and Technology 2018年第2期28卷 243-249页

作者： E.A.Novikov r.o.oshkin V.L.Shkuratnik S.A.Epshtein N.N.Dobryakova National University of Science and Technology(mISiS) Moscow 119049Russia

Traditional methods of coal thermal resistance char.cterization are informative but considerably timeconsuming and require utilization of a complex and expensive equipment. This limits the effectiveness of their application. In this paper, authors experimentally investigated potential application of thermally stimulated acoustic emission method for developing of relatively simple and rapid coals thermal resistance assessment method. Features of thermally stimulated acoustic emission of anthr.cite, lignites and bituminous coal samples subject to cyclic thermal loading have been experimentally *** the first time, it has been shown that there exists a relationship of such patterns with str.ctural parameters and properties of the coal samples, as well as their thermal resistance. The results indicate the possibility of applying the method of thermally stimulated acoustic emission to control pr.cesses of cryogenic disintegration and thermal resistance of fossil coals. The description of the equipment and methodological support needed for the implementation of this method have been provided.

关键词： Acoustic emission Fossil coal Thermal resistance cryogenic disintegration Str.cture Properties

Nano-silica-decorated Poly(m-Phenylene Isophthalamide)Separator with Enhanced mechanical and Electrolyte Wetting Properties for Lithium-Ion Batteries

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Transactions of Tianjin University 2020年第4期26卷 256-264页

作者： Jianjie Wang Biao Yuan Fusheng Pan lina Qiao Jun Guo cuijia Duan Wei Wu Zan chen anlei Su Key Laboratory for Green chemical Technology of ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China cenerTech Tianjin chemical research and Design Institute co. LtdTianjin 300131China collaborative Innovation center of chemical Science and Engineering(Tianjin) Tianjin 300072China

Heat-resistant poly(m-phenylene isophthalamide)(PmIA)has attr.cted considerable attention as a novel separator for application in lithium-ion batteries(LIBs);however,its mechanical strength and electrolyte wettability are not ***,a nano-silica-decorated poly(m-phenylene isophthalamide)(PmIA@Sio2)separator was fabr.cated with Sio2 nanoparticles uniformly attached to the pores and pore walls of the PmIA *** as-prepared PmIA@Sio2 separator has good mechanical strength(a 16%improvement compared with pristine PmIA)and wettability toward the electrolyte(the contact angle decreases from 34.0°to 23.1°).The PmIA@Sio2 separator also had a high ionic conductivity(0.75 mS/cm)and low interfacial electr.c resistance(75Ω).The assembled Licoo2/PmIA@Si o2-liquid electrolyte/Li cell displays good cycle performance with a capacity retention of 88.1%after 50 ***,the cycling performance and rate capacity rarely changed after high-temperature ***,the nano-silica-decorated PmIA separator is a potential candidate for application in LIBs with high safety.

关键词： Li-ion batteries PmIA@Sio2 Separator mechanical strength Electrolyte wetting

Effect of Alstonia scholaris bark extr.ct on testicular function of Wistar rats

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Asian Journal of Andrology 2002年第3期4卷 175-178页

作者： r. S. Gupta rakhi Sharma Aruna Sharma A.K. Bhatnager m.P. Dobhal Y.c. Joshi m.c. Sharma reproduction Physiology Section Department of Zoology University of Rajasthan Jaipur-302004 IndiaReproduction Physiology Section Department of Zoology University of Rajasthan Jaipur-302004 IndiaReproduction Physiology Section Department of Zoology University of Rajasthan Jaipur-302004 IndiaDepartment of Chemistry S.S. Jain Subodh P.G. College Jaipur-302004 IndiaRoswell Park Cancer Institute Elm & Carlton Streets Buffalo New York 14263 USADepartment of Chemistry University of Rajasthan Jaipur-302004 IndiaDepartment of Chemistry University of Rajasthan Jaipur-302004 India

Abstr.ct Aim: To evaluate the antifertility effect ofAlstonia scholaris bark extr.ct in male rats. methods: In male Wistar rats Alstonia scholaris bark extr.ct was given by oral route at a dose of 200 mg/day for 60 days. The fertility and testicular function were assessed by mating tests, sperm motility, sperm concentration, biochemical indices and testicular.cell population dynamics. results: oral feeding with the extr.ct at a dose of 200 mg/day for the period of 60 days did not cause body weight loss, while the weights of testes, epididymides, seminal vesicle and ventral prostate were significantly reduced. The production of step-19 spermatids was reduced by 79.6% in treated rats. The population of preleptotene and pachytene spermatocytes were decreased by 61.9% and 60.1%, respectively. Spermatogonia and Sertoli cell population were also affected. The seminiferous tubule and Leydig cell nuclear area were reduced significantly (Pcompared to the controls. reduced sperm count and motility resulted in a total suppression of fertility. A significant fall in the protein and sialic acid content of the testes, epididymides, seminal vesicle and ventral prostate as well as glycogen content of testes were also noticed. The fr.ctose content in the seminal vesicle was lowered whereas the testicular.cholesterol was elevated as compared with the controls. The following compounds were obtained from the extr.ct with chromatographic separation over Si-gel column: α-amyrin, β-amyrin, lupiol acetate, venenative, rhazine and yohimbine. conclusion: At the dose level employed, Alstonia scholaris bark extr.ct has a significant antifertility effect in male rats; the primary site of action may be post meiotic germ cells (Step 19 spermatids).

关键词： Alstonia scholaris testis sperm motility sialic acid Sertoli cells

The energy identity of mountainous areas:the example of Greece

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Journal of mountain Science 2018年第7期15卷 1429-1445页

作者： Nikolas m.KATSoULAKoS Dimitris c.KALIAmPAKoS National Technical University of Athens Metsovion Interdisciplinary Research Center National Technical University of Athens School of Mining and Metallurgical Engineering

mountainous areas have been long r.cognized as particularly important for the planet and sustainable mountain development is a global priority. In order to improve the socioeconomic development perspectives of mountain societies, efficient and well-targeted energy strategies should be formed. An important step towards this dir.ction is adequate understanding of local conditions and specific features that affect energy sector. This pr.cedure allows the inclusion of "locality" in energy planning and so, decentralized energy production is facilitated. The present study attempts to determine the particular energy identity of mountainous areas. Greece, which is the second most mountainous country in the EU, has been selected as a case study. Essential features of the mountainous space have been selected, namely altitude, inclination, remoteness, lack of productive activities, old buildings/vernacular architecture, in order to explore their interrelation with the energy sector. Based on literature review and research findings the inter.ction between mountainous char.cter and energy is outlined. Therefore, a framework of the char.cteristics of mountain energy identity is composed, which can provide support to the formation of specialized energy policy for mountainous areas. Some of the main findings of the present study include the significantly increased energy loads of mountainous areas, the abundance of renewable energy potential in high – altitude areas, the vulnerability of mountain societies to energy poverty and the difficulties in sitting energy projects in the restr.cted usable space of mountains. Since the literature regarding mountains and energy is rather poor the present paper aspires to be a step towards highlighting the importance of energy issues for mountain areas and societies. By determining the features of mountain energy identity energy planning in high – altitude areas and so, helping make energy planning more effective, such research works can be par

关键词： Energy demand renewable energy potential Energy poverty mountain energy policy mountain energy identity