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Terahertz Semiconductor Quantum Well Devices

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Journal of Semiconductors 2006年第4期27卷 627-634页

作者： liu H C luo H Ban D Waichter M Song C Y Wasilewski Z R Buchanan M Aers g C SpringThorpe A J Cao J C Feng S l Williams B S Hu Q Institute for Microstructural Sciences National Research Council Ottawa K1A 0R6 Canada State Key laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese AcademyofSciences Shanghai 200050 China Department of Electrical Engineering and Computer Science and Research laboratory of Electronics Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA

For eventually providing terahertz science with compact and convenient devices,terahertz (1～10THz) quantum-well photodetectors and quantum-cascade lasers are *** design and projected detector performance are presented together with experimental results for several test devices,all working at photon energies below and around optical *** limited infrared performance (BlIP) operations are observed for all samples (three in total),designed for different *** temperatures of 17,13,and 12K are achieved for peak detection frequencies of 9.7THz(31μm),5.4THz(56μm),and 3.2THz(93μm),respectively.A set of THz quantum-cascade lasers with identical device parameters except for doping concentration is *** δ-doping density for each period varies from 3.2×1010 to 4.8×*** observe that the lasing threshold current density increases monotonically with doping ***,the measurements for devices with different cavity lengths provide evidence that the free carrier absorption causes the waveguide loss also to increase *** the observed maximum lasing temperature is best at a doping density of 3.6×1010cm-2.

关键词：半导体量子论激光技术光电探测器

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绝缘铁粉在自行车永磁电动机中的应用

粉末冶金技术 2007年第2期25卷 145-151页

作者： C.g.l.nas J.Cros l.-P.lefebvre A.St-louis J.-Y.Dubé Ray guo 韩凤麟 Quebec Metal Powders limited Sorel-TracyQuébecCanaela laval University Ste-FoyQuébecCanada Industrial Materials Institute/NRCC BouchervilleQuébecCanada Maxtech Powder Metal Ste-FoyQuébecCanada Energy Propulsion System Asbestos QuébecCanada QMP Metal Powders(Asia Pacific) Hong KongChina

由于可减低成本,可减少每个部件的零件,同时铁粉复合材料具有各向同性,设计适应性大,因此绝缘铁粉正在用来替代用于电动机的钢片叠层材料。本文讲述了由铁粉复合材料定子制造永磁电动机样机所用的系统设计方法。介绍了开发这种定子的各... 详细信息

由于可减低成本,可减少每个部件的零件,同时铁粉复合材料具有各向同性,设计适应性大,因此绝缘铁粉正在用来替代用于电动机的钢片叠层材料。本文讲述了由铁粉复合材料定子制造永磁电动机样机所用的系统设计方法。介绍了开发这种定子的各个阶段,从最初的设计迭代到样品试验、用工业压机试验及生产。中心点是设计、材料及压制方面。

关键词：铁粉自行车永磁电动机 SMC 绝缘铁粉设计

Bile acid receptors and signaling crosstalk in the liver, gut and brain

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liver Research 2021年第3期5卷 105-118页

作者： Jessica M.Ferrell John Y.l.Chiang Integrative Medical Sciences Northeast Ohio Medical UniversityRootstownOHUSA

Bile acids are physiological detergents derived from cholesterol that aid in digestion and nutrient ab-sorption,and they play roles in glucose,lipid,and energy metabolism and in gut microbiome and metabolic *** acids mediate crosstalk between the liver and gut through bactericidal modulation of the gut microbiome,while gut microbes influence the composition of the circulating bile acid *** research indicates bile acids may also be important mediators of neurological disease by acting as peripheral signaling molecules that activate bile acid receptors in the blood-brain barrier and in the brain *** review hig.l.ghts the role of bile acids in maintaining.l.ver and gut microbe homeostasis,as well as their function as mediators of cellular signaling in the liver-gut-brain axis.

关键词： Bile acid metabolism Farnesoid X receptor(FXR) gut-brain axis Microbiome Neurodegenerative disease Takeda g protein-coupled receptor(TgR5)

Why use pre-differentiated cells to address complex multi-factorial neurodegenerative diseases?

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Neural Regeneration Research 2021年第7期16卷 1413-1414页

作者： Alex Kopyov Toni l.Uhlendorf Randy W.Cohen Celavie Biosciences llC OxnardCAUSA Department of Biology California State UniversityNorthridgeCAUSA

Past four decades have seen a concerted push to develop regenerative treatments for incurable neurodegenerative diseases such as Parkinson's disease(PD).PD's pathophysiology is primarily characterized by dopamine defi... 详细信息

关键词： diseases degenerative al.

The role of astronomical silicates during a cometary outburst

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Research in Astronomy and Astrophysics 2021年第3期21卷 184-192页

作者： Marcin Wesołowski College of Natural Sciences Institute of PhysicsUniversity of Rzesz´owPigonia 1 Street35-310 Rzesz´owPoland

This paper presents a new approach to analyzing the change of cometary *** our considerations,we assume that astronomical silicates(dust ag.l.merates)and gas are present in the *** assumption is a consequence of the analysis of the result observed during the Rosetta mission to comet67 P/Churyumov-gerasimenko(abbreviated 67 P/Ch-g).The dimensions of these ag.l.merates can be up to several ***,the large ones are few compared to particles with dimensions of several *** paper presents the results of calculations on the change in hypothetical comet brightness as a result of its *** calculations take into account the percentage of carbonaceous particles and silicates rich in magnesium.

关键词： comets general cometary outburst

DeepSun:machine-learning-as-a-service for solar flare prediction

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Research in Astronomy and Astrophysics 2021年第7期21卷 51-61页

作者： Yasser Abduallah Jason T.l.Wang Yang Nie Chang.l.u Haimin Wang Institute for Space Weather Sciences New Jersey Institute of TechnologyUniversity HeightsNewarkNJ 07102-1982USA Department of Computer Science New Jersey Institute of TechnologyUniversity HeightsNewarkNJ 07102-1982USA Big Bear Solar Observatory New Jersey Institute of Technology40386 North Shore LaneBig Bear CityCA 92314-9672USA Center for Solar-Terrestrial Research New Jersey Institute of TechnologyUniversity HeightsNewarkNJ 07102-1982USA

Solar flare prediction plays an important role in understanding and forecasting space *** main goal of the Helioseismic and Magnetic Imager(HMI), one of the instruments on NASA's Solar Dynamics Observatory, is to study the origin of solar variability and characterize the Sun's magnetic *** provides continuous full-disk observations of the solar vector magnetic field with high cadence data that lead to reliable predictive capability;yet, solar flare prediction effort utilizing these data is still limited. In this paper, we present a machine-learning-as-a-service(Mlaa S) framework, called Deep Sun,for predicting solar flares on the web based on HMI's data products. Specifically, we construct training data by utilizing the physical parameters provided by the Space-weather HMI Active Region Patch(SHARP)and categorize solar flares into four classes, namely B, C, M and X, according to the X-ray flare catalogs available at the National Centers for Environmental Information(NCEI). Thus, the solar flare prediction problem at hand is essentially a multi-class(i.e., four-class) classification problem. The Deep Sun system employs several machine learning algorithms to tackle this multi-class prediction problem and provides an application programming interface(API) for remote programming users. To our knowledge, Deep Sun is the first Mlaa S tool capable of predicting solar flares through the internet.

关键词： Sun:flares Sun:activity methods:data analysis

Analysis of Flashover Characteristics under Nanosecond Pulsed Coaxial Electric Field

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Journal of Electromagnetic Analysis and Applications 2009年第2期1卷 97-101页

作者： W. l. Huang J. F. Cui g. S. Sun 不详

Under nanosecond pulsed coaxial electric field, surface flashover voltage over the interfaces between nylon 1010 and transformer oil increases almost linearly with gap length, and the steeper rising edge of applied pulse, the higher flash-over voltage. Surface flashover properties are closely related to the electric field at the triple junctions of solid-liquid-electrode and the field gradient along the interfaces. Although the increased difference between inner and outer electrode radii will enhance electric field strength at the triple junctions and nonuniformity degree of potential distribution along interfaces, it reduces simultaneously terribly the surface field strength of coaxial inner electrode, so that flashover voltage doesn’t descend, but ascends almost linearly with gap length. The average flashover strength in coaxial electric field can be estimated by that in uniform electric field for large enough difference between inner and outer electrode radii, which is useful to practical engineering design for coaxial pulsed power apparatuses.

关键词： Pulsed Power Technology Coaxial Electrodes gap length Surface Flashover Triple Junctions Surface Potential

Up-reg.l.tion of muscarinic receptor of canine cerebral cortex by chronic treatment of a new anticholinergic drug

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中国药理学与毒理学杂志 1989年第3期3卷 196-196页

作者： Niu, W.-Z. Zhao, D.-l. liu, C.-g. China

Twelve dogs were divided into three groups. group 1 and 2 were injected im 0.015 and 0.9mg/kg of3-(2’-phenyl-2’cyclopentyl-2’hydroxyl-ethoxy) quinuclidine (8018) daily respectively for consecutive twelveweeks. gro... 详细信息

<正> Twelve dogs were divided into three groups. group 1 and 2 were injected im 0.015 and 0.9mg/kg of3-(2’-phenyl-2’cyclopentyl-2’hydroxyl-ethoxy) quinuclidine (8018) daily respectively for consecutive twelveweeks. group 3 (control) were injected im saline under the same conditions. All dogs were killed by

关键词： Up-reg.l.tion of muscarinic receptor of canine cerebral cortex by chronic treatment of a new anticholinergic drug

Anisian(Middle Triassic)Conodonts of the Kocaeli Triassic,Western Turkey

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Journal of Earth Science 2021年第3期32卷 616-632页

作者： Ali Murat Kilic Department of geological Engineering Faculty of EngineeringBalikesir UniversityBalikesirTurkey

The present study of Anisian(Middle Triassic)conodonts from the Kocaeli Peninsula(western Turkey)encompasses over 10 species of the families gondolellidae and gladigondolellidae,providing Early and Middle Triassic time constraints,Chiosella timorensis(Nogami,1968);Cornudina oezdemirae gedik,1975;gladigondolella tethydis(Huckriede,1958);Neostrachanognathus tahoensis Koike,1998;Paragondolella aegaea(Bender,1970);Paragondolella bulgarica Budurov and Stefanov,1975;Nicoraella kockeli(Tatge,1956);***(Sudar and Budurov,1979),and gladigondolella *** established are Paragondolella hirschii *** and Budurov;*** *** ,Budurov,Petrunova and Mirauta;and *** ***.K?l??.The Kocaeli Anisian conodonts show a faunal affinity with *** present Anisian fauna is characteristic of the *** strong homeomorphy that characterizes the Anisian in western North America is discussed.

关键词： Triassic Anisian Aegean Bithynian conodonta gebze(Kocaeli)