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A well-resolved uudd cyclic water tetramer was reported in the crystal host of [Cu(adipate)(4,4-bipyridine)].(H(2)O)(2), showing the contribution of the water cluster to the stability of the crystal host and the role of cooperative association of the water cluster and the crystal host in the formation of the water cluster. 相似文献
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This paper studies the drain current collapse of AlGaN/GaN metal-insulator-semiconductor high electron-mobility transistors (MIS-HEMTs) with NbAlO dielectric by applying dual-pulsed stress to the gate and drain of the device.For NbAlO MIS-HEMT,smaller current collapse is found,especially when the gate static voltage is 8 V.Through a thorough study of the gate-drain conductance dispersion,it is found that the growth of NbAlO can reduce the trap density of the AlGaN surface.Therefore,fewer traps can be filled by gate electrons,and hence the depletion effect in the channel is suppressed effectively.It is proved that the NbAlO gate dielectric can not only decrease gate leakage current but also passivate the AlGaN surface effectively,and weaken the current collapse effect accordingly. 相似文献
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制备了一系列通过苯氧基修饰的聚(苯乙烯-异丙烯膦酸)磷酸氢锆(ZPS-IPPA)轴向固载手性MnⅢ(Salen)催化剂,并将其应用于苯乙烯的环氧化反应。催化结果表明：苯氧链接手臂邻位取代基对于环氧化结果有重要影响,相比邻位取代基为-H和-CH3,取代基为t-Bu基团时,催化剂能够提供更高水平的对映选择性。同时,比较了两种长度几乎一致的链接手臂(-NH-C6H4-NH-,-O-C6H4-O-),结果表明：在没有轴向助剂N-甲基玛琳氮氧化物(NMO)参与下,在间氯过氧苯甲酸(m-CPBA)为氧化剂的体系中, 链接手臂-O-C6H4-O-比-NH-C6H4-NH-更有利于取得优异的催化效果。制备的非均相催化剂在前5次后催化活性与对映选择性几乎没有明显的变化。 相似文献
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The behaviours of three types of hot-hole injections in ultrashortchannel lightly doped drain (LDD) nMOSFETs with ultrathin oxideunder an alternating stress have been compared. The three types ofhot-hole injections, i.e. low gate voltage hot hole injection(LGVHHI), gate-induced drain leakage induced hot-hole injection(GIDLIHHI) and substrate hot-hole injection (SHHI), have differentinfluences on the devices damaged already by the previous hotelectron injection (HEI) because of the different locations oftrapping holes and interface states induced by the three types ofinjections, i.e. three types of stresses. Experimental results showthat GIDLIHHI and LGVHHI cannot recover the degradation of electrontrapping, but SHHI can. Although SHHI can recover the device'sperformance, the recovery is slight and reaches saturation quickly,which is suggested here to be attributed to the fact that trappedholes are too few and the equilibrium is reached between thetrapping and releasing of holes which can be set up quickly in theultrathin oxide. 相似文献
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CuO/Sn0.8Ti0.2O2催化剂的表征及对NO+CO反应活性研究 总被引：2，自引：0，他引：2
Reducibility and characteristics of CuO/Sn0.8Ti0.2O2 catalysts were examined by using a microreactor-GC NO+CO reaction system, BET, TG-DTA, FTIR, XRD and H2-TPR techniques. CuO/Sn0.8Ti0.2O2 had high activity in NO+CO reaction, showing 93% NO conversion at 300 ℃ in air, and 100% NO conversion at 225 ℃ after H2 pretreatment. The pore size distribution of Sn0.8Ti0.2O2 was mainly as micro-pores and meso-pores (1~5 nm), and the specific surface area and total pore volume of Sn0.8Ti0.2O2 were 69 m2·g-1 and 0.15 cm3·g-1, respectively. As shown by XRD analysis, there was no CuO crystal diffraction peak at 9%CuO loading, but two CuO crystal diffraction peaks at 2θ 35.5° and 38.7° were present at 12% CuO loading. FTIR detected the adsorption of NO and CO on the surface of reduced 12%CuO/Sn0.8Ti0.2O2. The Cu2+ sites and support surface adsorbed NO, and the process of NO adsorption led to the formation of N2O and NO3-. In contrast, the Cu+、Cu0 sites and support surface adsorbed CO, and when the mixed gases of NO and CO were adsorbed by support surface, no NO3- was formed. H2-TPR showed four reduction peaks (α, β, γ and δ). The α, β and γ peaks were the reductions of CuO species, and the δ peak was the reduction of Sn0.8Ti0.2O2. 相似文献
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A specially designed experiment is performed for investigating gate-induceddrain leakage (GIDL) current in 90nm CMOS technology using lightly-dopeddrain (LDD) NMOSFET. This paper shows that the drain bias $V_{rm D}$ has astrong effect on GIDL current as compared with the gate bias $V_{rm G}$ at thesame drain--gate voltage $V_{rm DG}$. It is found that the difference between$I_{rm D}$ in the off-state $I_{rm D}-V_{rm G}$ characteristics and thecorresponding one in the off-state $I_{rm D}-V_{rm D}$ characteristics, which isdefined as $I_{rm DIFF}$, versus $V_{rm DG}$ shows a peak. The difference betweenthe influences of $V_{rm D}$ and $V_{rm G}$ on GIDL current is shownquantitatively by $I_{rm DIFF}$, especially in 90nm scale. The difference isdue to different hole tunnellings. Furthermore, the maximum $I_{rm DIFF}$($I_{rm DIFF,MAX})$ varies linearly with $V_{rm DG}$ in logarithmic coordinatesand also $V_{rm DG}$ at $I_{rm DIFF,MAX}$ with $V_{rm F}$ which is the characteristicvoltage of $I_{rm DIFF}$. The relations are studied and some relatedexpressions are given. 相似文献
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Cheng-Bin Liang Jin-Rong Tian Run-Qin Xu Yan-Rong Song Yun-Feng Wu Zi-Kai Dong 《中国物理 B》2020,(7):378-384
We demonstrate a self-started,long-term stable polarization-maintaining mode-locked fiber laser based on the nonlinear polarization evolution technique.A polari... 相似文献
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Harry Miyosi Silalahi Yu-Chih Chiang Shih-Hung Lin Yan-Rong Jiang Chia-Yi Huang 《Laser u0026amp; Photonics Reviews》2024,18(2):2300659
This work proposes a quick measurement of the refractive index of dielectric nanofilm via a fabricated topological grating that comprises indium tin oxide (ITO) strips and nanowalls with an extremely high aspect ratio of 25. As the topological grating is capped with a dielectric nanofilm, the parabolic fields of the nanowalls destructively interfere with those of the ITO strips. This destructive interference weakens the photonic jets of the topological grating, decreasing its diffraction efficiency. The decrease in the diffraction efficiency determines the refractive index of the nanofilm without measuring its thickness in advance because the efficiency decrease is independent of the thickness. In other words, the photonic jets of the topological grating are manipulated by the refractive index of the nanofilm. The experimental results verify that refractive indices of titanium-dioxide, silicon-dioxide, and bovine-serum-albumin nanofilms with a thickness much smaller than the visible wavelengths can be measured by using the proposed topological grating. Therefore, topological gratings have great potential to develop advanced materials, fascinating devices, and innovative instruments. 相似文献