排序方式: 共有24条查询结果,搜索用时 15 毫秒
1.
Nanoparticles of platinum and hydrous molybdenum oxide (Pt/HxMoO3) were successfully electrodeposited onto poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) (PEDOT-PSS) film by chronocoulometry (0.2 C). Various loadings of Pt/HxMoO3 particles onto the PEDOT-PSS electrode were achieved using the co-deposition technique. The existence of Pt/HxMoO3 particles was determined through characterization by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis. XPS results revealed that deposited Pt and molybdenum were metallic Pt and HxMoO3, respectively. XRD analysis showed a decrease of Pt crystalline facets for the incorporation of HxMoO3 into PEDOT-PSS-Pt, indicating a strong interaction between Pt and HxMoO3. Scanning electron microscopy (SEM) results revealed a uniform dispersion of Pt/HxMoO3 particles, with the particle size of 70–90 nm, in the PEDOT-PSS matrix. The cyclic voltammetry study and chronopotentiometry measurements demonstrated that the PEDOT-PSS-Pt/HxMoO3 electrode had superior electrocatalytic activity of methanol oxidation with less CO poisoning. The presence of amorphous HxMoO3 particles on the Pt surface minimized CO poisoning of methanol oxidation. 相似文献
2.
A muscle thermal rigorometer was constructed, allowing muscle shortenings induced by dynamic heating or isothermal aging to be monitored. Operating isothermally like a traditional rigorometer at 10 °C, postmortem dorsal muscle shortening (S10°C) developing from 0% to 10% of its initial length in corresponding to RIfiber along fiber‐direction developing from 0% to 100% within 16 h was monitored for freshwater tilapia. Monitoring meat cooking in the dynamic heating mode, heat‐induced shortenings could be observed for all muscle samples possessing different degrees of rigor induced by 10°C aging. The heat‐induced shortening (Sdynamic) plus its 10°C aging shortening (S10°C) for each sample was the same, Soverall= S10°C+ Sdynamic= 10%. Their heat‐induced shortening peak temperatures (Ts) from 30°C to 48°C were inversely correlated with the sample RIfiber from 0% to near 100%. These findings together with an additional calcium/adenosine triphosphate (ATP) model studies showed that the ATPase related myofibrillar contractile system was responsible for these low‐temperature cooking shortenings, which along with Ts values could thus be adopted as new rigor indices. 相似文献
3.
Silicon - Inverted pyramid (IP) texturization on silicon wafers has recently attracted attention for the structure’s light trapping ability and low specific surface area. The later property... 相似文献
4.
Hsien-Chin Chiu Chung-Wen Chen Yuan-Chang Huang 《Electron Devices, IEEE Transactions on》2008,55(1):256-260
The microwave noise, power, and linearity characteristics of pseudomorphic high electron mobility transistors (pHEMTs) with various lower/upper planar delta-doped ratios were systematically evaluated and studied. By varying the lower/upper delta-doped ratio from 1:1 to 1:4, both Schottky gate turn-on voltage VON and breakdown voltage VBR were reduced. In addition, higher upper delta-doped design is effective in improving the device current density, transconductance, output power, and power-added efficiency; however, this design also scarified the flatness of transconductance distribution and Schottky performance, resulting in a degradation of device linearity. As to the noise performance, after increasing the upper delta-doped concentration by more than 2 times 1012 cm-2, the minimum noise figure NFmin can be reduced to a stable range, and higher current density cannot efficiently improve the noise performance. Although the 1:4 design provided the largest power density of pHEMT, its high gate leakage current at high input power swing limited its linearity, and 1:3 design achieved the best linearity performance. 相似文献
5.
Chung-Wen Cho Yi-Hung Wu Arbee L. P. Chen 《Journal of Intelligent Information Systems》2009,32(1):23-51
In this paper, we propose a novel algorithm for mining frequent sequences from transaction databases. The transactions of
the same customers form a set of customer sequences. A sequence (an ordered list of itemsets) is frequent if the number of customer sequences containing it satisfies the user-specified threshold. The 1-sequence is a special type of sequences because it consists of only a single itemset instead of an ordered list, while the k-sequence is a sequence composed of k itemsets. Compared with the cost of mining frequent k-sequences (k ≥ 2), the cost of mining frequent 1-sequences is negligible. We adopt a two-phase architecture to find the two types of frequent
sequences separately in order that the discovery of frequent k-sequences can be well designed and optimized. For efficient frequent k-sequence mining, every frequent 1-sequence is encoded as a unique symbol and the database is transformed into one constituted
by the symbols. We find that it is unnecessary to encode all the frequent 1-seqences, and make full use of the discovered
frequent 1-sequences to transform the database into one with a smaller size. For every k ≥ 2, the customer sequences in the transformed database are scanned to find all the frequent k-sequences. We devise the compact representation for a customer sequence and elaborate the method to enumerate all distinct
subsequences from a customer sequence without redundant scans. The soundness of the proposed approach is verified and a number
of experiments are performed. The results show that our approach outperforms the previous works in both scalability and execution
time. 相似文献
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7.
提出了一种新的时钟性能驱动的增量式布局算法,它针对目前工业界较为流行的标准单元布局,应用查找表模型来计算延迟.由于在布局阶段较早地考虑到时钟信息,可以通过调整单元位置,更有利于后续的有用偏差时钟布线和偏差优化问题.来自于工业界的测试用例结果表明,该算法可以有效地改善合理偏差范围的分布,而对电路的其它性能影响很小. 相似文献
8.
Hsien-Chin Chiu Yuan-Chang Huang Chung-Wen Chen Liann-Be Chang 《Electron Devices, IEEE Transactions on》2008,55(3):721-726
This paper elucidates the dc, pulse I-V, microwave, flicker noise, and power properties of AlGaAs/InGaAs pseudomorphic high electron mobility transistors (pHEMTs) after various ex situ sulfur pretreatments. The pHEMTs were pretreated with NH4OH, (NH4)2SX, and P2S5/(NH4)2SX solutions before SiO2 passivation to reduce the GaAs native oxide-related surface states. Stable phosphorus oxides and sulfur bound to the Ga and As species can be efficiently obtained using P2S5/(NH4)2SX pretreatment; therefore, the leakage current in pHEMT was reduced following this process. Atomic force microscopy measurements indicated that the phosphorus oxides formed by P2S5/(NH4)2SX treatment also provided a better surface roughness than obtained following traditional (NH4)2SX-only pretreatment, reducing mobility degradation after sulfur pretreatment. Based on the dc and 1 mus pulse I-V measurement results, P2S5/(NH4)2SX-treated pHEMT exhibited very similar Ids trends, especially at high currents; however, NH4OH, (NH4)2SX treatments clearly reduced the current upon pulse measurement because of the presence of surface traps. Hence, this novel pretreatment method has great potential for highly linear microwave power transistor applications. 相似文献
9.
利用钢板酸洗废液、镍电镀废液、铜电镀废液及锌电镀废液,以适量各废液调配,以ICP-AES检测其浓度,经化学共沉法而获得镍铜锌铁氧磁粉,热处理使晶粒长大,增大模具成型生胚密度,经烧结得环状体,测量其性质,经XRD,SEM,TEM及VSM等检测分析,实验结果显示镍铜锌铁氧磁粉晶体为尖晶石立方结构,晶粒大小为8~20 nm,饱和磁束密度为31.6 emu/g,经过750 ℃热处理饱和磁束密度为52.3 emu/g.烧结环状体晶粒大小为1~3 μm,饱和磁束密度为60.7 emu/g(3670 Gauss). 相似文献
10.
Energy-aware scheduling and simulation methodologies for parallel security processors with multiple voltage domains 总被引:1,自引:1,他引:0
Yung-Chia Lin Yi-Ping You Chung-Wen Huang Jenq Kuen Lee Wei-Kuan Shih Ting-Ting Hwang 《The Journal of supercomputing》2007,42(2):201-223
Dynamic voltage scaling (DVS) and power gating (PG) have become mainstream technologies for low-power optimization in recent
years. One issue that remains to be solved is integrating these techniques in correlated domains operating with multiple voltages.
This article addresses the problem of power-aware task scheduling on a scalable cryptographic processor that is designed as
a heterogeneous and distributed system-on-a-chip, with the aim of effectively integrating DVS, PG, and the scheduling of resources
in multiple voltage domains (MVD) to achieve low energy consumption. Our approach uses an analytic model as the basis for
estimating the performance and energy requirements between different domains and addressing the scheduling issues for correlated
resources in systems. We also present the results of performance and energy simulations from transaction-level models of our
security processors in a variety of system configurations. The prototype experiments show that our proposed methods yield
significant energy reductions. The proposed techniques will be useful for implementing DVS and PG in domains with multiple
correlated resources. 相似文献