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991.
LIAO Kai CUI XiaoXin LIAO Nan MA KaiSheng WU Di WEI Wei LI Rui YU DunShan 《中国科学:信息科学(英文版)》2014,(4):269-281
With the technology scaling down, low power dissipation has become one of the research focuses in the field of integrated circuit design. Various types of adiabatic logics have been invented for low-power applications. However, the expanding leakage current degrades the performance of conventional adiabatic logics. In this article, a novel improved complementary pass-transistor adiabatic logic (ICPAL) based on fin-type field- effect transistor (FinFET) devices with ultra-low power dissipation has been presented. The proposed ICPAL takes full advantage of different FinFET operating modes, that is, shorted-gate mode, independent-gate mode, and low-power mode, to make a tremendous reduction in power dissipation. For explication and verification, the power dissipation of different ICPAL standard cells has been investigated and compared with other types of adiabatic circuits based on FinFETs. The results show that the ICPAL circuits have ultra-low power dissipation in a wide range of clock frequencies(30-800 MHz) under the condition of similar number of transistors, and the average reduction in power dissipation is about 23.1%, 75.0%, and 50.0% relative to 2N-2N2P, improved pass- transistor adiabatic logic, and complimentary pass-transistor adiabatic logic, respectively. Furthermore, ICPAL supports a better pre-evaluation of system power dissipation in VLSI design and has an intrinsic characteristic for the resistance to some types of side channel attacks. 相似文献
992.
Jim D. Earls Jerry E. White Marvin L. Dettloff Marty J. Null 《Journal of Coatings Technology and Research》2004,1(3):243-245
Epoxidized 10-undecenoic acid triglyceride, an experimental seed oil derivative that has a terminal epoxy group on each of
the three acyl glyceride segments, has been found to have good reactivity with amine curatives and allows room temperature
cures to be obtained. Coatings based on epoxidized 10-undercenoic acid triglyceride have also shown excellent UV stability.
As an example, coatings samples placed in a QUVA chamber exhibit no loss in gloss after 3000 hr of a cycled exposure to high
intensity UV lamps and moisture at temperatures of 50–60°C. In comparison, coatings based on standard liquid epoxy resins
(LERs) and commercially available hydrogenated LERs lose gloss due to chalking/decomposition within 200–800 hr.
Presented at the 81 st Annual Meeting of the Federation of Societies for Coatings Technology, November 12–14, 2003, in Philadelphia,
PA. 相似文献
993.
994.
The pulsed arc discharge to the surface of wastewater was applied to the degradation of a textile azo dye (Acid Red 27). A
high-voltage electrode (discharging electrode) was vertically placed above the surface of the wastewater while the wastewater
itself was grounded. The pulsed arc discharge occurred between the tip of the discharging electrode and the surface of the
wastewater, producing various oxidative species. Oxygen was used as the working gas instead of air to prevent nitrogen oxides
from forming. The effect of several parameters on the chromaticity and chemical oxygen demand (COD) removal was examined.
The results obtained showed that the chromaticity of the wastewater was completely removed by this process and the COD also
decreased significantly. It has been found that ozone formed in the gas phase mainly affects the removal of the dye. The contribution
of other effects such as ultraviolet light emission and OH radical formation during the arc discharge to the degradation of
the dye was found to be less than 15%. For the present reactor system, the optimum pH, pulse repetition rate and agitation
speed were found to be 3.0, 110 Hz and 300 rpm, respectively. 相似文献
995.
996.
喷雾热解法制备高纯超细氧化铝粉 总被引:3,自引:0,他引:3
本文以高纯硫酸铝铵为原料,用喷雾热解法制得纯度大于99.9%、细度为10 ̄20nm的高纯超细α-Al2O3粉。探讨喷雾热解工艺条件对粉体性能的影响。 相似文献
997.
Salimur Choudhury Kai Salomaa Selim G. Akl 《International Journal of Parallel, Emergent and Distributed Systems》2014,29(2):147-177
Due to the advent of sensor technology and its applications, mobile wireless sensor networks (MWSNs) have gained a significant amount of research interest. In a typical MWSN, sensors can move within the network. We develop a set of probabilistic and deterministic cellular automaton (CA)-based algorithms for motion planning problems in MWSNs. First, we consider a scenario where a group of sensors are deployed and they need to disperse in order to maximise the area covered by the network. In this variant of the problem we do not explicitly consider that the sensors should maintain the connectivity of the network while they move. Second, we consider a scenario where the sensors are initially randomly distributed and they need to disperse autonomously to both maximise the coverage of the network and maintain its connectivity. We carry out extensive simulations of both deterministic and randomised variants of the algorithms. For the first variant of the problem we compare our algorithms with one previous algorithm and find that our algorithm yields better network coverage than the earlier algorithm. We also find that probabilistic algorithms have better overall performance for the second variant. CA algorithms rely only on local information about the network and, hence, they can be used in practice for MWSN problems. On the other hand, locality of the algorithm implies that maintaining connectivity becomes a non-trivial problem. 相似文献
998.
Crop residue,manure and fertilizer in dryland maize under reduced tillage in northern China: I grain yields and nutrient use efficiencies 总被引:4,自引:0,他引:4
Xiaobin Wang Dianxiong Cai Willem B. Hoogmoed Udo D. Perdok Oene Oenema 《Nutrient Cycling in Agroecosystems》2007,79(1):1-16
The rapidly increasing population and associated quest for food and feed in China has led to increased soil cultivation and
nitrogen (N) fertilizer use, and as a consequence to increased wind erosion and unbalanced crop nutrition. In the study presented
here, we explored the long-term effects of various combinations of maize stover, cattle manure and nitrogen (N) and phosphorus
(P) fertilizer applications on maize (Zea mays L.) yield and nutrient and water use efficiencies under reduced tillage practices. In a companion paper, we present the effects
on nutrient balances and soil fertility characteristics. The ongoing factorial field trial was conducted at Shouyang Dryland
Farming Experimental Station in northern China from 1993 onwards. The incomplete, determinant-optimal design comprised 12
treatments, including a control treatment, in duplicate. Grain yields and N, P, and potassium (K) uptakes and N, P and K use
efficiencies were greatly influenced by the amount of rain during the growing season (GSR), and by soil water at sowing (SWS).
There were highly significant interactions between GSR and added stover and manure, expressed in complex annual variations
in grain yield and N, P and K use efficiencies. Annual mean grain yields ranged from 3,000 kg ha−1 to 10,000 kg ha−1 and treatment mean yields from 4,500 kg ha−1 to 7,000 kg ha−1. Balanced combination of stover (3,000–6,000 kg), manure (1,500–6,000 kg) and N fertilizer (105 kg) gave the highest yield.
Stover and manure were important for supplying K, but the effects differed greatly between years. Overall mean N recovery
efficiency (NRE) ranged from 28% to 54%, depending on N source. NRE in wet years ranged from 50% to 90%. In conclusion, balanced
combinations of stover, manure and NP fertilizer gave the highest yield and NRE. Reduced tillage with adding stover and manure
in autumn prior to ploughing is effective in minimizing labor requirement and wind erosion. The potentials of split applications
of N fertilizer, targeted to the need of the growing crop (response farming), should be explored to further increase the N
use efficiency. 相似文献
999.
Prakorn Ramakul Milan Hronec Ura Pancharoen 《Korean Journal of Chemical Engineering》2007,24(2):282-287
−Purification of 2-mercaptobenzothiazole (91.9% purity) by solvent extraction was studied. The extraction of impurities present
in crude 2-MBT (e.g. benzothiazole, sulfides and sulfur containing compounds) was carried out at temperatures between 70-180°C
using various solvents and their mixtures of different polarity. The highest purity of 2-MBT, above 99% was obtained using
nitrobenzene, toluene and ethanol, even at a concentration of 2-MBT above 50 wt%. Increasing temperature and decreasing concentration
of the raw material have a positive influence on the purification process. A comparable efficiency of purification was observed
also with mixed solvents, (toluene with ethanol, acetone and aniline) possessing the same polarities. A correlation between
the polarity indexes (PI) of mixed solvents and experimentally obtained purity of 2-MBT was found. The highest purity of 2-MBT
provides extraction of the raw material with mixed solvents having PI 3.8-4.4. 相似文献
1000.
Sibel Akgün Gülsüm Ekici Nilüfer Mutlu Necati Beşirli Baki Hazer 《Journal of Polymer Research》2007,14(3):215-221
Modification of chitosan by grafting of vinyl butyrate was carried out in homogeneous phase using potassium persulfate as
redox initator and 1.5% acetic acid as solvent. The percent grafting and grafting efficiency were analysed and the high grafting
efficiency up to 94% was observed. The effects of reaction variables such as monomer concentration, initiator concentration,
temperature and reaction time were investigated. It was observed that the solubility of chitosan was markedly reduced after
grafting with vinyl butyrate. The grafted product is insoluble in common organic solvents as well in dilute organic and inorganic
acids. Characterization of the graft copolymers were carried out by using Fourier Transform Infrared Spectroscopy (FTIR),
Differential Scanning Calorimetry (DSC) and Scanning Electron Microscopy (SEM) technics. Characteristic signal of carbonyl
group was observed at 1,731 cm−1 which belongs to the poly vinyl butyrate segments in the graft copolymer. The melting transition of the chitosan main chain
in the copolymer shifted to 124°C from its original value 101°C. In addition to these, we have also studied topology of the
graft copolymer and the SEM micrograph showed continuous homogenous matrix which means there is no phase separation. 相似文献