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1.
Silicon - We investigate the performance of a dielectric modulated dual-metal double-gate with low-k/high-k oxide stack junctionless MOSFET (DM-DG-LK/HK-S JL-MOSFET) based sensor device for...  相似文献   
2.
Zinc oxide (ZnO) nanoparticles assembled in one dimension to give rod‐shaped morphology were synthesized. The effect of these ZnO nanoparticles (average particle size ~ 50 nm) as the curing agent for carboxylated nitrile rubber was studied with special attention to cure characteristics, mechanical properties, dynamic mechanical properties, and swelling. These results were compared with those of the conventional rubber grade ZnO. The study confirmed that the ZnO nanoparticles gave a better state of cure and higher maximum torque with a marginal decrease in optimum cure time and scorch time. The mechanical properties also showed an improvement. There was an increase in tensile strength by ~ 120%, elongation at break by ~ 20%, and modulus at 300% elongation by ~ 30% for the vulcanizate cured with ZnO nanoparticles, as compared with the one containing rubber grade ZnO. Dynamic mechanical analysis revealed that the vulcanizates exhibited two transitions—one occurring at lower temperature due to the Tg of the polymer, while the second at higher temperature corresponding to the hard phase arising due to the ionic structures. The second transition showed a peak broadening because of an increase in the points of interaction of ZnO nanoparticles with the matrix. The tan δ peak showed a shift towards higher Tg in the case of ZnO nanoparticle‐cured vulcanizate, indicating higher crosslinking density. This was further confirmed by volume fraction of rubber in the swollen gel and infrared spectroscopic studies. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   
3.
Superior thermal conductivity of single-layer graphene   总被引:42,自引:0,他引:42  
We report the measurement of the thermal conductivity of a suspended single-layer graphene. The room temperature values of the thermal conductivity in the range approximately (4.84+/-0.44)x10(3) to (5.30+/-0.48)x10(3) W/mK were extracted for a single-layer graphene from the dependence of the Raman G peak frequency on the excitation laser power and independently measured G peak temperature coefficient. The extremely high value of the thermal conductivity suggests that graphene can outperform carbon nanotubes in heat conduction. The superb thermal conduction property of graphene is beneficial for the proposed electronic applications and establishes graphene as an excellent material for thermal management.  相似文献   
4.
The morphology of hybrid organic–inorganic perovskite films is known to strongly affect the performance of perovskite‐based solar cells. CH3NH3PbI3‐xClx (MAPbI3‐xClx) films have been previously fabricated with 100% surface coverage in glove boxes. In ambient air, fabrication generally relies on solvent engineering to obtain compact films. In contrast, this work explores the potential of altering the perovskites microstructure for solar cell engineering. This work starts with CH3NH3PbI3‐xClx, films with grain morphology carefully controlled by varying the deposition speed during the spin‐coating process to fabricate efficient and partially transparent solar cells. Devices produced with a CH3NH3PbI3‐xClx film and a compact thick top gold electrode reach a maximum efficiency of 10.2% but display a large photocurrent hysteresis. As it is demonstrated, the introduction of different concentrations of bromide in the precursor solution addresses the hysteresis issues and turns the film morphology into a partially transparent interconnected network of 1D microstructures. This approach leads to semitransparent solar cells with negligible hysteresis and efficiencies up to 7.2%, while allowing average transmission of 17% across the visible spectrum. This work demonstrates that the optimization of the perovskites composition can mitigate the hysteresis effects commonly attributed to the charge trapping within the perovskite film.  相似文献   
5.
Basic mechanisms through which men and women self-regulate arousal have received little attention in human experimental addiction research, although stress-response-dampening and craving theories suggest an important role of emotional arousal in motivating alcohol use. This study examined gender differences in the effects of acute alcohol intoxication on psychophysiological and self-reported arousal in response to emotionally negative, positive, and neutral, and alcohol-related, picture cues. Thirty-six social drinkers (16 women) were randomly assigned to an alcohol, placebo, or control beverage group and exposed to picture cues every 10 s (0.1 Hz presentation frequency). Psychophysiological arousal was assessed via a 0.1-Hz heart rate variability (HRV) index. A statistically significant beverage group-by-gender interaction effect on psychophysiological, but not self-reported, arousal was found. The 0.1-Hz HRV responses to picture cues were suppressed by alcohol only in men. This gender-specific suppression pattern did not differ significantly across picture cue types. There were no significant gender differences in the placebo or control group. Greater dampening of arousal by alcohol intoxication in men, compared with women, may contribute to men’s greater tendency to use alcohol to cope with stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Zinc oxide (ZnO) nanoparticles were synthesized by homogeneous precipitation and calcination method and were then characterized by transmission electron microscopy and X‐ray diffraction analysis. Synthesized ZnO was found to have no impurity and had a dimension ranging from 30–70 nm with an average of 50 nm. The effect of these ZnO nanoparticles as cure activator was studied for the first time in natural rubber (NR) and nitrile rubber (NBR) and compared with conventional rubber grade ZnO with special reference to mechanical and dynamic mechanical properties. From the rheograph, the maximum torque value was found to increase for both NR and NBR compounds containing ZnO nanoparticles. ZnO nanoparticles were found to be more uniformly dispersed in the rubber matrix in comparison with the conventional rubber grade ZnO as evident from scanning electron microscopy/X‐ray dot mapping analysis. The tensile strength was observed to improve by 80% for NR when ZnO nanoparticles were used as cure activator instead of conventional rubber grade ZnO. An improvement of 70% was observed in the case of NBR. The glass transition temperature (Tg) showed a positive shift by 6°C for both NR and NBR nanocomposites, which indicated an increase in crosslinking density. The swelling ratio was found to decrease in the case of both NR and NBR, and volume fraction of rubber in swollen gel was observed to increase, which supported the improvement in mechanical and dynamic mechanical properties. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   
7.
Clustering in mobile ad hoc network (MANET) play a vital role in improving its basic network performance parameters like routing delay, bandwidth consumption and throughput. One-hop clustering scheme adopts the simple mechanism to make the logical partition of the dynamic network where the network topology changes constantly resulting an unstable clustering. This paper makes a comprehensive survey of some bench-mark one-hop clustering algorithms to understand the research trends in this area. The literature provides the logic of cluster formation for different algorithms in achieving a linked cluster architecture and an intensive simulation survey of their performance on the cluster maintenance aspects such as cluster density, frequency of cluster reelection, frequency of cluster changes by the nodes and the granularity of cluster heads. This paper should facilitate the researchers as well as practitioners in choosing a suitable clustering algorithm on the basis of their formation and maintenance overhead, before any routing scheme is adopted in the mobile ad hoc network.  相似文献   
8.
9.
Low cost and environment-friendly bio-oils are gaining market value as a plasticizer for elastomeric compounds. Unsaturated triglycerides of bio-oils can be easily modified in various ways, like epoxidation, esterification, and so on. In the present work, 15 mole percentage of the total double bond content of the neem oil (NO) was epoxidized by acetic acid-hydrogen peroxide system to synthesize epoxidized neem oil (ENO). NO and ENO were characterized by nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry. The effect of ENO on the properties of nonpolar styrene butadiene rubber (SBR) and polar nitrile rubber (NBR) was investigated. Tear strength (69.9 N/mm), abrasion resistance index (ARI) (68.2) and hardness (64 shore A) of the SBR/ENO compound were comparable to the compound containing total distillate aromatic extract (TDAE) (values: 70.8 N/mm, 68.0 and 64 shore A respectively). Tensile strength and ARI of conventional NBR/dioctyl phthalate (DOP) compound were 24.9 MPa and 107 respectively, whereas NBR/ENO compound showed improved tensile strength (26.9 MPa), and ARI (138). Tear strength (83.4 N/mm) and hardness (74 shore A) of NBR/ENO were comparable to the tear strength (83.5 N/mm) and hardness (74 shore A) of NBR/DOP compound. Hence, the multifunctional additive property of ENO makes it a cheap and sustainable replacement of TDAE and DOP.  相似文献   
10.
Microsystem Technologies - We investigate the effect of aspect ratio (AR) with a given fin width (Wfin) of hybrid FinFETs at channel length of 20 nm on their digital performance using...  相似文献   
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