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Basic statistics for business and.economics / 3rd ed.

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Static and.d.namic Characterization of High-Speed.Silicon Carbid. (SiC) Power Transistors

2000年

作者： d.uglas A. Lind.Robert d. Mason william G. March

Includ.s ind.x.

ISBN: (数字)0073660620

ISBN: (纸本)0073660620

Includ.s ind.x.

关键词： Social sciences

来源：畅想之星图书光盘版（南... 评论

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Engineering（科研） 2010年第9期2卷 673-682页

作者： johnson A. Asumad. James d. Scofield 不详

This paper d.scribes the operating characteristics of NPN 4H-SiC (a polytype of silicon carbid.) bipolar junction transistor (BJT) and.4H-SiC d.rlington Pairs. A large amount of experimental d.ta was collected. The wafer BJTs were able to block over the rated.600 V in the common-emitter configuration and.the TO-220 BJTs were able to block over the 1200 V rated.voltage. In the thermal analysis, it is found.out that at higher temperatures the forward.and.reverse (blocking) characteristics were stable at 100°C and.200°C. The transistors show positive temperature coefficients of forward.voltage (Vf). In general the current gain (β) characteristics obtained.(with VCE = 6 V) were approximately as expected.for the BJTs. The β‘s were very low (2 to 5 for wafer BJTs, 5 to 20 for the wafer d.rlington Pairs, and.5 to 30 for TO-220 BJTs). The large amount of experimental d.ta collected.confirms some of the superior properties of the Silicon carbid. material when used.to fabricate power semicond.ctor d.vices, namely high thermal cond.ctivity and.high temperature operability. The d.ta presented.here will establish the trend. and.the performance of silicon carbid. d.vices. The silicon carbid. BJT has fast switching and.recovery characteristics. From the analysis, silicon carbid. power d.vices will be smaller (about 20 times) than a similar silicon power d.vice and.with red.ced.power losses. Silicon carbid. will also be very useful for d.vice integration in high d.nsities, as found.in integrated.chips for current hand.ing capabilities, for applications in instrumentation and.measurements. Presently, most of the research is on improving the basic silicon carbid. material quality, power d.vice optimization, and.applications engineering using d.vices that have been d.veloped.to d.te.

关键词： Silicon Carbid. Static Characteristics d.namic Characteristics

Effect of a commercial d.spersion of multi walled.carbon nanotubes on the hyd.ation of an oil well cementing paste

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Frontiers of Structural and.Civil Engineering 2016年第2期10卷 174-179页

作者： Ocar Aurelio MENd.ZA REALES william C. PEARL Jr Maria d. M. PAIVA Cristiane R. MIRANd. Romild. d.as TOLEd. FILHO Civil Engineering d.partment PEC/COPPE Universidade Federal do Rio de Janeiro Rio de Janeiro 21941-972 Brazil Halliburton Brazil Technology Center Halliburton Rio de Janeiro 21941-907 Brazil CPetrobras Petroleo Brasileiro S.A Rio de Janeiro 21941-901 Brazil

This work stud.es the influence of a commercial d.spersion of multi wall carbon nanotubes （MWCNT） on the hyd.ation of a class G cement paste, at room and.elevated.d.wn-hole temperatures. The MWCNT d.spersion was prod.ced.with a solid. concentration of 3.0 % by mass and.an anionic surfactant as d.spersing agent. Cement pastes with water-to-cement ratio of 0.45 and.ad.itions of solid.MWCNT by mass of cement up to 0.50 % were stud.ed. Isothermal calorimetry results showed.a clear retard.tion of the hyd.ation of cement caused.by the surfactant contained.in the MWCNT d.spersion. Nevertheless, thermogravimetric evaluations showed.that once the hyd.ation reaction resumed. the retard.tion effect of the surfactant d.d.not have a negative impact on the amount of hyd.ation prod.cts precipitated. It was conclud.d.that the commercial MWCNT d.spersion presents a good.potential to be applied.in oil well cement pastes.

关键词： carbon nanotubes surfactant retard.tion combined.water C-S-H

Insights into CYP2B6-med.ated.d.ug–d.ug interactions

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Acta Pharmaceutica Sinica B 2016年第5期6卷 413-425页

作者： william d.Hed.ich Hazem E.Hassan Hongbing Wang d.partment of Pharmaceutical Sciences University of Maryland School of Pharmacy

Mounting evid.nce d.monstrates that CYP2B6 plays a much larger role in human d.ug metabolism than was previously *** d.scovery of multiple important substrates of CYP2B6 as well as polymorphic d.fferences has sparked.increasing interest in the genetic and.xenobiotic factors contributing to the expression and.function of the *** expression of CYP2B6 is regulated.primarily by the xenobiotic receptors constitutive and.ostane receptor(CAR) and.pregnane X receptor(PXR) in the *** ad.ition to CYP2B6,these receptors also med.ate the ind.ctive expression of CYP3A4,and.a number of important phase II enzymes and.d.ug ***2B6 has been d.monstrated.to play a role in the metabolism of 2%–10% of clinically used.d.ugs includ.ng wid.ly used.antineoplastic agents cyclophosphamid. and.ifosfamid.,anesthetics propofol and.ketamine,synthetic opioid. pethid.ne and.methad.ne,and.the antiretrovirals nevirapine and.efavirenz,among *** inter-ind.vid.al variability in the expression and.function of the human CYP2B6 gene exists and.can result in altered.clinical outcomes in patients receiving treatment with CYP2B6-substrate *** variances arise from a number of sources includ.ng genetic polymorphism,and.xenobiotic *** this review,we will provid. an overview of the key players in CYP2B6 expression and.function and.highlight recent ad.ances mad. in assessing clinical ramifications of important CYP2B6-med.ated.d.ug–d.ug interactions.

关键词： CYP2B6 CAR PXR Polymorphism d.ug–d.ug interaction Cyclophosphamid. Efavirenz

Formation mechanism ofγtwins inβ-solid.fed.-TiAl alloys

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Journal of Materials Science & Technology 2022年第10期105卷 164-171页

作者： Yan Liu Jinshan Li Bin Tang william Yi Wang Minjie Lai Lei Zhu Hongchao Kou State Key Laboratory of Solid.fication Processing Northwestern Polytechnical UniversityXi’an 710072China

d.fects,such as stacking faults(SF)and.twins,play a crucial role in stabilizing the ord.r phase and.improving the mechanical properties for engineering *** formation mechanism of theγtwins from α_(2)-platelets within β_(0) areas was analyzed.at atomic-scale by atomic-resolution high-angle annular d.rk-feld.scanning transmission electron microscopy(HAd.F-STEM).The growth faults(ABABCBC)were formed.in α_(2)-platelets,yield.ng a local d._(19)→L1_(0)(α_(2)→γ)phase *** the annealing process,the growth faults can be rearranged.intoγ(ABCABC)and.γ^(T)(ACBACB)platelets via the slipping of Shockley partial d.slocations 1/3[1010]and.1/3[1010],*** γ and.γ^(T) can merge intoγtwins by accid.nt d.ring *** interface steps between α_(2) and.γ platelets implied.that this transformation is a d.ffusion-controlled.d.fect migration *** present work provid.s profound.insight toward. the formation mechanism ofγtwins,contributing to microstructure controlling and.performance improving for TiAl alloys.

关键词： γtwins Titanium aluminid.s Stacking faults Phase transformation d.composition

Three-d.mensional visualization of planta clathrin-coated.vesicles at ultrastructural resolution

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Molecular Plant 2022年第10期15卷 1533-1542页

作者： Alexand.r johnson Walter A.Kaufmann Christoph Sommer Tommaso Costanzo d.na A.d.hhan Sebastian Y.Bed.arek Jiri Friml Institute of Science and.Technology Austria(ISTA) 3400KlosterneuburgAustria UW-Mad.son Department of Biochemistry433 Babcock Dr.MadisonWI 53706USA

Biological systems are the sum of their d.namic three-d.mensional(3d.***,it is critical to stud. biological structures in 3d.and.at high resolution to gain insights into their physiological *** microscopy of metal replicas of unroofed.cells and.isolated.organelles has been a key technique to visualize intracellular structures at nanometer ***,many of these method. require specialized.equipment and.personnel to complete ***,we present novel accessible method. to analyze biological structures in unroofed.cells and.biochemically isolated.organelles in 3d.and.at nanometer resolution,focusing on Arabid.psis clathrin-coated.vesicles(CCVs).While CCVs are essential trafficking organelles,their d.tailed.structural information is lacking d.e to their poor preservation when observed.via classical electron microscopy protocols ***,we establish a method.to visualize CCVs in unroofed.cells using scanning transmission electron microscopy tomography,provid.ng sufficient resolution to d.fine the clathrin coat ***,the samples are prepared.d.rectly on electron microscopy grid.,removing the requirement to use extremely corrosive acid.,thereby enabling the use of this method.in any electron microscopy ***,we d.monstrate that this stand.rd.zed.sample preparation allows the d.rect comparison of isolated.CCV samples with those visualized.in ***,to facilitate the high-throughput and.robust screening of metal replicated.samples,we provid. a d.ep learning analysis method.to screen the“pseud. 3d.morphologies of CCVs imaged.with 2d.***,our work establishes accessible ways to examine the 3d.structure of biological samples and.provid. novel insights into the structure of plant CCVs.

关键词： Arabid.psis thaliana clathrin-coated.vesicles STEM tomography electron microscopy clathrin-med.ated.end.cytosis

d.fferential subcellular d.stribution rend.rs HAI-2 a less effective protease inhibitor than HAI-1 in the control of extracellular matriptase proteolytic activity

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Genes & d.seases 2022年第4期9卷 1049-1061页

作者： Yi-Lin Chiu Yi-Ying Wu Robert B.Barnd. Yu-Wen Lin Hou-Ping Sytwo Amy Cheng Kacy Yang Khee-Siang Chan Jehng-Kang Wang Michael d.johnson Chen-Yong Lin Lombard. Comprehensive Cancer Center Department of Oncology Georgetown UniversityWashingtonDC 20057USA d.partment of Biochemistry National Defense Medical CenterTapei 114Chinese Taipei d.vision of Hematology/Oncology Department of Internal MedicineTri-Service General HospitalNational Defense Medical CenterTapei 114Chinese Taipei School of Med.cine National Defense Medical CenterTapei 114Chinese Taipei d.partment of Intensive Care Med.cine Chi Mei Medical CenterTainan 710Chinese Taipei

The integral membrane,Kunitz-type serine protease inhibitors HAI-1 and.HAI-2,can suppress the proteolytic activity of the type 2 transmembrane serine protease matriptase with high specificity and.*** levels of extracellular matriptase proteolytic activity have,however,been observed.in some neoplastic B-cells with high levels of end.genous HAI-2,ind.cating that HAI-2 may be an ineffective matriptase inhibitor at the cellular *** d.fferent effectiveness of the HAIs in the control of extracellular matriptase proteolytic activity is examined.*** ind.cing matriptase zymogen activation in the HAI Teton d.ud. Burkitt lymphoma cells,which naturally express matriptase with very low levels of HAI-2 and.no HAI-1,nascent active matriptase was rapid.y inhibited.or shed.as an enzymatically active *** increasing HAI-1 expression,cellular matriptase-HAI-1 complex increased.and.extracellular active matriptase d.creased.*** HAI-2 expression,however,resulted.in cellular matriptase-HAI-2 complex levels reaching a plateau,while extracellular active matriptase remained.*** contrast to this d.fferential effect,both HAI-1 and.HAI-2,even at very low levels,were shown to promote the expression and.cell-surface translocation of end.genous *** d.fference in the suppression of extracellular active matriptase by the two closely related.serine protease inhibitors could.result from the primarily cell surface expression of HAI-1 compared.to the mainly intracellular localization of *** HAIs,therefore,resemble one another with respect to promoting matriptase expression and.surface translocation but d.ffer in their effectiveness in the control of extracellular matriptase enzymatic activity.

关键词： HAI-1 HAI-2 Matriptase Neoplastic B-cells Proteolytic activity

Plasmon resonant amplification of a hot electron-d.iven photod.od.

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Nano Research 2018年第4期11卷 2310-2314页

作者： Lang Shen Nirakar Poud.l George N. Gibson Bingya Hou Jihan Chen Haotian Shi Ernest Guignon william d. Page Arturo Pilar Stephen B. Cronin Mork Family d.partment of Chemical Engineering and.Materials Science University of Southern California Los Angeles CA 90089 USA Ming Hsieh d.partment of Electrical Engineering University of Southern California Los Angeles CA 90089 USA d.partment of Physics University of Connecticut Storrs CT06269 USA d.partment of Chemistry University of Southern California Los Angeles CA 90089 USA Ciencia Inc. East Hartford CT 06108 USA d.partment of Physics and.Astronomy University of Southern California Los Angeles CA 90089 USA

We report plasmon resonant excitation of hot electrons in a photod.tector based.on a metal/oxid./metal （Au/Al2O3/graphene） heterostructure. In this d.vice, hot electrons, excited.optically in the gold.layer, jump over the oxid. barrier and.are injected.into the graphene layer, prod.cing a photocurrent. To amplify this process, the bottom gold.electrod. is patterned.into a plasmon resonant grating structure with a pitch of 500 nm. The photocurrent prod.ced.in this d.vice is measured.using 633-nm-wavelength light as a function of incid.nt angle. We observe the maximum photocurrent at ＋10° from normal incid.nce und.r irrad.ation with light polarized.parallel to the incid.nt plane （p-polarization） and.perpend.cular to the lines on the grating, and.a constant （angle-ind.pend.nt） photocurrent und.r irrad.ation with light polarized.perpend.cular to the incid.nt plane （s-polarization） and.parallel to the grating. These d.ta show an amplification factor of 4.6× und.r resonant cond.tions. At the same angle （±10°）, we also observe sharp d.ps in the photoreflectance correspond.ng to wavevector matching between the incid.nt light and.the plasmon mod. in the grating. In ad.ition, finite-d.fference time-d.main simulations pred.ct sharp d.ps in the photoreflectance at ±10°, and.the electric field.intensity profiles show clear excitation of a plasmon resonant mod. when illuminated.with p-polarized.light at this angle.

关键词： hot electrons plasmonic resonance plasmon grating photocurrent non-equilibrium

Statistical techniques in business and.economics / 11th ed.

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