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Design of refractory multi-principal-element alloys for high-temperature applications

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npj Computational Materials 2023年第1期9卷 884-893页

作者： Gaoyuan Ouyang Prashant Singh Ranran Su Duane D.Johnson Matthew J.Kramer John H.Perepezko Oleg N.Senkov Daniel miracle Jun Cui Division of Materials Science and Engineering Ames LaboratoryAmesIA 50011USA Department of Materials Science and Engineering University of Wisconsin-MadisonMadisonWI 53706USA Department of Materials Science and Engineering Iowa State UniversityAmesIA 50011USA Air Force Research Laboratory Materials and Manufacturing DirectorateWright-Patterson Air Force BaseDaytonOH 45433USA

Refractory multi-principal-element alloys(RMPEAs)exhibit high specific strength at elevated temperatures(T).However,current RMPEAs lack a balance of room-temperature(RT)ductility,high-T strength,and high-T creep *** density-functional theory methods,we scanned composition space using four criteria:(1)formation energies for operational stability:-150250 GPa;(3)inverse Pugh ratio for ductility:G/b2500°*** rapid bulk alloy synthesis and characterization,we validated theory and down-selected promising alloy compositions and discovered Mo72.3W12.8Ta10.0Ti2.5Zr2.5 having well-balanced RT and high-T mechanical *** alloy has comparable high-T compressive strength to well-known MoNbTaW but is more ductile and more creep *** is also superior to a commercial Mo-based refractory alloy and a nickel-based superalloy(Haynes-282)with improved high-T tensile strength and creep resistance.

关键词： creep alloy alloys

Expression of an endoglucanase from Tribolium castaneum （TcEG 1 ） in Saccharomyces cerevisiae

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Insect Science 2014年第5期21卷 609-618页

作者： Derek Shirley Cris Oppert Todd b. Reynolds b.thany miracle brenda Oppert William E. Klingeman Juan Luis Jurat-Fuentes Department of Entomology and Plant Pathology University of Tennessee Department of Microbiology University of TennesseeKnoxville TN 37996 USDA-Agricultural Research Service Center for Grain and Animal Health Research Manhattan KS 66502 Department of Plant Sciences University of Tennessee Knoxville TN 37996 USA

Insects are a largely unexploited resource in prospecting for novel cellulolytic enzymes to improve the production of ethanol fuel from lignocellulosic biomass. The cost of lignocellulosic ethanol production is expected to decrease by the combination of cellulose degradation （saccharification） and fermentation of the resulting glucose to ethanol in a single process, catalyzed by the yeast Saccharomyces cerevisiae transformed to express efficient cellulases. While S. cerevisiae is an established heterologous expression system, there are no available data on the functional expression of insect cellulolytic enzymes for this species. To address this knowledge gap, S. cerevisiae was transformed to express the full-length cDNA encoding an endoglucanase from the red flour beetle, Tribolium castaneum （TcEG 1）, and evaluated the activity of the transgenic product （rTcEG 1）. Expression of the TcEG1 cDNA in S. cerevisiae was under control of the strong glyceraldehyde-3 phosphate dehydrogenase promoter. Cultured transformed yeast secreted rTcEG1 protein as a functional β-1,4-endoglucanase, which allowed transformants to survive on selective media containing cellulose as the only available carbon source. Evaluation of substrate specificity for secreted rTcEG1 demonstrated endoglucanase activity, although some activity was also detected against complex cellulose substrates. Potentially relevant to uses in biofuel production rTcEG1 activity increased with pH conditions, with the highest activity detected at pH 12. Our results demonstrate the potential for functional production of an insect cellulase in S. cerevisiae and confirm the stability of rTcEG1 activity in strong alkaline environments.

关键词： biofuels insect cellulase Saccharomyces cerevisiae Tribolium castaneum yeast

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夏洛的网(一)

疯狂英语（初中天地） 2024年第5期 55-56页

作者： E.b.White 不详

在朱克曼家的谷仓里,这是威尔伯与夏洛的第一次友好交流。这段对话揭示了两个不同物种之间可能发展出深厚友谊的种子,为这个经典故事的展开奠定了基础。

关键词：经典故事威尔伯朱克曼夏洛的网友好交流深厚友谊

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Transformation Kinetics and Diffusion Mechanisms of boron in Discontinuously Reinforced Ti Matrix Composites

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Transformation Kinetics and Diffusion Mechanisms of Boron in...

biodiversity science blossoms in China

第十三届国际复合材料会议

作者： C.Riviello D.b.miracle R.Srinivasan A.O. Smith Corp. Electrical Products Co Tipp City OH USA Air Force Research Laboratory Materials and Manufacturing Directorate Wright-Patterson AFB OH USA Dept of Mechanical and Materials Engineering Wright State University Dayton OH USA

Introduction Discontinuously reinforced Ti matrix composites offer higher specific modulus, specific strength and wear resistance compared to unreintbrced Ti alloys. These materials also offer nearly isotropic properties and the ability to be processed using conventional metalworking techniques. The purpose of this study was to establish the feasibility of producing discontinuously reinforced Ti (DRTi) with the equilibrium Tib phase (Fig. 1) via a blended elemental powder metallurgy (P/M) processing route. The basic kinetics of diffusion were determined to provide a predictive framework for control of the Ti+Tib 2Tib reaction.

关键词： discontinuously-reinforced Ti Tib growth kinetics diffusion coefficient

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National Science Review 2021年第7期8卷 60-61页

作者： Richard b.Primack biology Department Boston University

Over the past 35 years, China has been transformed by an economic miracle unlike anything seen in the history of the world. Hundreds of millions of people have emerged from rural poverty, cities have been re-built, cutting-edge industries have been established and a modern transportation network now knits together the country. This transformation has come at a significant cost to the environment, in terms of air pollution, water pollution, the loss and fragmentation of habitats, and threats of species extinction. Yet, as the review by Mi et al.(2021) points out, China is also now emerging as a leader in biodiversity conservation and research [1].

关键词： PROTECTED AREAS

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诺基亚无线音效转接器AD-5b

数字通信 2003年第22期 21-21页

作者： miracle

诺基亚无线音效转接器AD-58的最大作用是让不具备蓝牙功能的手机也能够享受到蓝牙耳机。用户只要将诺基亚无线音效转接器AD-5b插入兼容的诺基亚手机

关键词：音效转接器连接器 AD-5b 诺基亚

对晚期慢性心力衰竭患者行心脏再同步化治疗致NYHA分级改善的临床预测因素和时机:多中心InSync随机临床评价(miracle)和多中心InSyncICD随机临床评价(miracle-ICD)试验的结果

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世界核心医学期刊文摘（心脏病学分册） 2006年第9期2卷 13-13页

作者： Pires L.A. Abraham W.T. Young J.b. Johnson K.M. 刘少伟 Heart Rhythm Center St.John Hospital and Medical Center22101 Moross RdDetroitMI 48236United StatesDr

background: based on current patient selection criteria, a significant proportion of recipients of cardiac resynchronization therapy(CRT) do not respond to treatment. The purpose of this analysis is to identify predictors and characterize the timing of response to CRT in patients with advanced heart failure. Methods: Patients randomized to receive CRT in the miracle and miracle-ICD trials, designed to assess the benefit of CRT compared with standard medical therapy in patients with advanced heart failure, left ventricular ejection fractionbaseline to the 6-month follow-up were considered responders and those who had no change or worse NYHA class or died were classified as nonresponders. Responders were subdivided into early(within 1-3 months) and late(6 months). Results: One hundred forty-three(64%) of 224 and 190(61%) of 313 patients in the miracle and miracleICD trials, respectively, responded to therapy, with 81(57%) of 143 and 100(53%) of 190 responding early. Several but differing factors predicted CRT response and timing in the two trials with a high sensitivity(89%-90%) but, owing to a low specificity(31%-49%), a modest predictive accuracy(66%-75%). Conclusions: based on improvement of ≥1 NYHA class, less than two thirds of patients enrolled in the miracle or miracle-ICD trials responded to CRT, with just more than half responding within the first month. Several factors predicted CRT response and timing, but given their modest predictive accuracy, comparable for both studies, additional methods for selecting candidates most likely to benefit from CRT are needed.

关键词：心脏再同步化治疗慢性心力衰竭患者 NYHA分级晚期心力衰竭预测因素 InSync 随机分配 D试验

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