检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

温度标准的现状

国外计量 1976年第6期 25-29页

作者： t.j.quinn 袁先富

一、序言温度计量咨询委员会1971年第五届温度讨论会的一个重要结果是建立四个工作小组,以便对该委员会在温度计量各个方面进行咨询。在拟订1968年国际实用温标(IPtS—68)时所得到的经验说明,温度计量是这样的复杂,将来修订温标需要事先进

关键词：温度计量热力学温标定义水沸点不确定度修订版本铂电阻温度计定容气体温度计光电高温计

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

国际计量的最新进展

现代计量测试 1998年第1期6卷 3-6,28页

作者： t.j.quinn 高蔚国家计量局中国计量科学研究院

国际计量的最新进展Ｔ．Ｊ．Ｑｕｉｎｎ（国家计量局ＢＩＰＭ局长）自从我从事国际计量局（ＢＩＰＭ）工作二十多年以来，国际计量发生了巨大的变化。与１９６２年我在英国国家物理所（ＮＰＬ）工作时相比，各国国家计量院的状况已大... 详细信息

国际计量的最新进展Ｔ．Ｊ．Ｑｕｉｎｎ（国家计量局ＢＩＰＭ局长）自从我从事国际计量局（ＢＩＰＭ）工作二十多年以来，国际计量发生了巨大的变化。与１９６２年我在英国国家物理所（ＮＰＬ）工作时相比，各国国家计量院的状况已大不相同。那时，国际间的联系虽然存在...

关键词：国际计量学进展等效性结构化体系

在线全文

学校读者我要写书评

暂无评论

1968年国际实用温标的展望

宇航计测技术 1986年第4期 23-23页

作者： t.j.quinn 纪然波国际计量局

自68国际实用温标正式通过以来,巳将近二十年了。这段时间内一直围绕继68国际实用温标之后的温标可能形式展开讨论。的确,在相当一段时间里认为1987年可能为通过新温标的日期。在70年代末期,有关计温学方面大量新工作已经取得成果。从0.... 详细信息

自68国际实用温标正式通过以来,巳将近二十年了。这段时间内一直围绕继68国际实用温标之后的温标可能形式展开讨论。的确,在相当一段时间里认为1987年可能为通过新温标的日期。在70年代末期,有关计温学方面大量新工作已经取得成果。从0.5K 至金点1337K 整个范围内,热力学温度的测量已基本上完成或取得很大的进展。我们发现,热力学温度与国际实用温标明显不同,其差值比原来所估计的要大得多,特别是在0℃至460℃范围内。在0℃以下,铂电阻温度计内插方程的新工作表明,可建设一个新方程,比68温标中所使用的更精确更简单,此外还大大

关键词：国际温标内插铂电阻温度计光学高温计不接触式温度仪表

Identific tion of quantitative trait loci and associated candidate genes for pregnancy success in Angus–Brahman crossbred heifers

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

journal of Animal Science and Biotechnology 2024年第1期15卷 162-170页

作者： quinn A.Hoorn Gabriel A.Zayas Eduardo E.Rodriguez Laura M.jensen Raluca G.Mateescu Peter j.Hansen Department of Animal Sciences Donald Henry Barron Reproductive and Perinatal Biology Research Programand the Genetics InstituteUniversity of FloridaGainesvilleFLUSA School of Applied Systems Biology La Trobe UniversityBundooraVIC 3083Australia

Background In beef cattle, more than 50% of the energy input to produce a unit of beef is consumed by the female that produced the calf. Development of genomic tools to identify females with high genetic merit for reproductive function could increase the profitability and sustainability of beef *** Genome-wide association studies(GWAS) were performed using a single-step genomic best linear unbiased prediction approach on pregnancy outcome traits from a population of Angus–Brahman crossbred heifers. Furthermore, a validation GWAS was performed using data from another farm. Heifers were genotyped with the Bovine GGP F250 array that contains 221,077 SNPs. In the discovery population, heifers were bred in winter breeding seasons involving a single round of timed artificial insemination(AI) followed by natural mating for 3 months. two phenotypes were analyzed: pregnancy outcome to first-service AI(PAI;n = 1,481) and pregnancy status at the end of the breeding season(PEBS;n = 1,725). the heritability was estimated as 0.149 and 0.122 for PAI and PEBS, respectively. In the PAI model, one quantitative trait locus(QtL), located between 52.3 and 52.5 Mb on BtA7, explained about 3% of the genetic variation, in a region containing a cluster of γ-protocadherin genes and SLC25A2. Other QtLs explaining between 0.5% and 1% of the genetic variation were found on BtA12 and 25. In the PEBS model, a large QtL on BtA7 was synonymous with the QtL for PAI, with minor QtLs located on BtA5, 9, 10, 11, 19, and 20. the validation population for pregnancy status at the end of the breeding season were Angus–Brahman crossbred heifers bred by natural mating. In concordance with the discovery population, the large QtL on BtA7 and QtLs on BtA10 and 12 were *** In summary, QtLs and candidate SNPs identified were associated with pregnancy outcomes in beef heifers, including a large QtL associated with a group of protocadherin genes. Confirmation of these associations

关键词： Beef cattle Fertility GWAS QtL

the secondary injury cascade after spinal cord injury:an analysis of local cytokine/chemokine regulation

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第6期19卷 1308-1317页

作者： Daniel j.Hellenbrand Charles M.quinn Zachariah j.Piper Ryan t.Elder Raveena R.Mishra taylor L.Marti Phoebe M.Omuro Rylie M.Roddick jae Sung Lee William L.Murphy Amgad S.Hanna Department of Neurosurgery University of Wisconsin-Madison School of Medicine and Public HealthMadisonWIUSA Department of Biomedical Engineering University of Wisconsin-MadisonMadisonWIUSA Department of Orthopedics and Rehabilitation University of Wisconsin-MadisonMadisonWIUSA Department of Materials Science and Engineering University of Wisconsin-MadisonMadisonWIUSA Forward BIO Institute University of Wisconsin-MadisonMadisonWIUSA

After spinal cord injury,there is an extensive infiltration of immune cells,which exacerbates the injury and leads to further neural ***,a major aim of current research involves targeting the immune response as a treatment for spinal cord *** much research has been performed analyzing the complex inflammatory process following spinal cord injury,there remain major discrepancies within previous literature regarding the timeline of local cytokine *** objectives of this study were to establish an overview of the timeline of cytokine regulation for 2 weeks after spinal cord injury,identify sexual dimorphisms in terms of cytokine levels,and determine local cytokines that significantly change based on the severity of spinal cord *** were inflicted with either a mild contusion,moderate contusion,severe contusion,or complete transection,7 mm of spinal cord centered on the injury was harvested at varying times post-injury,and tissue homogenates were analyzed with a Cytokine/Chemokine 27-Plex *** demonstrated pro-inflammatory cytokines including tumor necrosis factorα,interleukin-1β,and interleukin-6 were all upregulated after spinal cord injury,but returned to uninjured levels within approximately 24 hours post-injury,while chemokines including monocyte chemoattractant protein-1 remained upregulated for days *** contrast,several anti-inflammatory cytokines and growth factors including interleukin-10 and vascular endothelial growth factor were downregulated by 7 days *** spinal cord injury,tissue inhibitor of metalloproteinase-1,which specifically affects astrocytes involved in glial scar development,increased more than all other cytokines tested,reaching 26.9-fold higher than uninjured *** a mild injury,11 cytokines demonstrated sexual dimorphisms;however,after a severe contusion only leptin levels were different between female and male *** conclusion,pro-inflammatory cytokines in

关键词： astrocytes chemokines cytokines inflammation macrophages microglia secondary damage spinal cord injury

In situ characterization of particle formation in spray flame synthesis using wide-angle light scattering

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第3期86卷 304-312页

作者： Simon Aβmann Franz j.t.Huber Stefan Will Lehrstuhl für technische thermodynamik(Ltt) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91058Germany Erlangen Graduate Schoolin Advanced Optical technologies(SAOt) Friedrich-Alexander-Universitat Erlangen-Nurnberg(FAU)Erlangen91052Germany Competence Unit Engineering of Advanced Materials(EAM) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91052Germany

Wide-angle light scattering(WALS)was used for in situ measurements of droplet and nanoparticle size distributions during the synthesis of titania and iron oxide particles from liquid precursor solutions in the standardized SpraySyn burner for spray flame *** was synthesized from titanium tetraisopropoxide(ttIP)and iron oxide from iron(II)nitrate nonahydrate(INN)using ethanol(EtOH)as *** images were taken at heights up to 120 mm above the burner surface and classified into droplet and particle *** size distributions were derived from a sequential analysis of scattering data containing the oscillating Mie pattern,the lognormal size distribution parameters for spherical and fractal particle fractions from a multivariate approach on averaged particle scattering *** results show that the precursor addition leads to altered evaporation behavior and even droplet disruption probably induced by puffing or micro-explosions compared to pure *** the case of ttIP(a hygroscopic alkoxide),the synthesis of a large fraction of spheres was observed,while the nitrate INN leads to the formation of mostly fractal aggregates.

关键词： Spray flame synthesis Metal oxide particles Elastic light scattering Droplet size distribution Nanoparticle morphology Particle size distribution

Reply to the note by Li Piani et al.

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence technology（防务技术） 2024年第1期31卷 603-606页

作者： t.Li Piani j.Weerheijm L.j.Sluys tU Delft Stevinweg 12628 CNDelftthe Netherlands tNO PO Box 452280 AARijswijkthe Netherlands NLDA Faculty of Military Sciences1781 CADen Helderthe Netherlands

In 2017,a ballistic phenomenological model was proposed by the authors of Ref.[1] to numerically simulate the experimental depths of small caliber projectiles impacting walls made of *** opportunity for a new model in the field revealed from the observation that two older models recently used by the authors of Ref.[2] shared a linear relationship between the penetration depth P and the impacting velocity v_(O).

关键词： Penetration Adobe Modeling

Mathematical modelling of ball and plate system with experimental and correlation function-based model validation

在线全文

学校读者我要写书评

暂无评论

Control theory and technology 2024年第2期22卷 326-341页

作者： t.R.Dil Kumar S.j.Mija Department of Electrical Engineering National Institute of Technology CalicutKozhikode673601KeralaIndia

the ball and plate system is an inherently nonlinear under actuated benchmark system used for validating the performance of various control schemes. A mathematical model depicting the dynamics close to that of the system is very much required for such a test bed. In this correspondence, the complete nonlinear model, a simplified nonlinear model, and a linearized model of the ball and plate system are developed. the system comprises a ball and plate mechanism and a rotary servo unit. the ball and plate mechanism is modelled using the Euler–Lagrange method, whereas the rotary servo subsystem is modelled from the first principles. the nonlinear model of the combined system is developed by including the dynamics of the servo motor with gear and rolling resistance between the ball and the plate. the simplified nonlinear model of the system is obtained with suitable assumptions. the model is linearized around the operating point using the jacobian. the validity of the developed models is investigated through correlation function analysis. the open-loop response of the three models, viz., nonlinear, simplified nonlinear, and linearized models, is analyzed in the MAtLAB/Simulink platform. Since the open-loop system is unstable, the experimental validation of the model is performed with a double-loop PSO (particle swarm optimization) PID control scheme.

关键词： Ball and plate system Correlation function Model validation Particle swarm optimization(PSO) PSO PID controller

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.t.jeong S.W.Lee W.j.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

the superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth