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排序方式: 共有342条查询结果,搜索用时 46 毫秒
41.
Barbara A Williams Antonius F B van der Poel Huug Boer Seerp Tamminga 《Journal of the science of food and agriculture》1997,74(1):117-124
Wheat (Triticum aestivum L) straw and corn (Zea mays L) silage were extruded under variable conditions of temperature and screw speed. The resulting extrudates were then tested for their fermentability according to cumulative production of gas, and compared with each other and with the untreated material. VFA analysis was carried out at the end of fermentation, to assess the pattern of fermentation. Analysis of the cumulative gas curves showed significant differences between substrates. Extrusion treatment also led to significant differences, though the effect of screw speed and temperature were not always consistent. However, most differences in cumulative gas production were negative, particularly for wheat straw, which suggests that, under the conditions used, extrusion actually reduced the fermentability of the fibres. © 1997 SCI. 相似文献
42.
Jong-Tae Park Antonius Suwanto Irawan Tan Tommy Nuryanto Rudy Lukman Kan Wang Jay-lin Jane 《Food science and biotechnology》2014,23(1):125-132
An α-amylase gene was cloned from the thermophilic bacterium Bacillus subtilis isolated from Indonesian oil palm shell waste. The gene expressed an extracellular enzyme. Optimal hydrolysis conditions for the enzyme were 70°C and pH 6.0. The specific activity of the enzyme was 16.0 kU per mg of protein, which was higher than for other thermostable amylases. Hydrolytic products of the enzyme using starch and glycogen were mainly maltohexaose and maltopentaose. The enzyme had a K m value of 0.099 mg/mL for amylopectin, more than 10 times lower than for amylose. The catalytic efficiency of the enzyme using amylopectin was 39,200 mL/mg·s and was 3,270 mL/mg·s using amylose. The enzyme liquefied corn starch at pH 5.0, which was successfully converted to glucose using commercial glucoamylase and pullulanase without pH adjustment. The enzyme has advantages for industrial applications. 相似文献
43.
在多用户MIMO系统下行链路中,块对角化(Block diagonalization, BD)预编
码算法的和速率性能要优于匹配滤波算法(Matched filter, MF)和迫零算法(Zero forc
i
ng, ZF)。然而,传统的BD算法利用矩阵分解来构造除当前用户的其他所有用户信道的零空
间,需要O(N2)浮点运算次数(Float point operations, FLOPs)。当
基站的天线数N趋向于大规模时,BD算法计算复杂度巨大。本文
提出一种基于投影子方法构造其他用户合成信道的零空间的BD算法,该算法仅需O(
N)FLOPs。仿真表明:同传统的BD算法相比,本文所提出的低复杂度BD算法显著地降低
了实现复杂度,而和速率性能损失微小,仍然优于MF和ZF,并且当N趋
向于大规模时,它的和速率性能趋向于传统的BD算法和SVD算法。 相似文献
44.
Game and Dynamic Communication Path-Based Pricing Strategies for Microgrids Under Communication Interruption 下载免费PDF全文
Bo Zhang Chunxia Dou Dong Yue Ju H.Park Yudi Zhang Zhanqiang Zhang 《IEEE/CAA Journal of Automatica Sinica》2023,10(4):1032-1047
Nowadays,the microgrid cluster is an important application scenario for energy trading.In trading,one of the most important research directions is the issue of pricing.To determine reasonable pricing for the microgrid cluster,data communication is used to create the cyber-physical system(CPS),which can improve the observability of microgrids.Then,the following works are carried out in the CPS.In the physical layer:1) Regarding trading between microgrids and the load,based on the generalized game... 相似文献
45.
Aibek Sarimbekov Lukas Stadler Lubomír Bulej Andreas Sewe Andrej Podzimek Yudi Zheng Walter Binder 《Software》2016,46(8):1053-1089
Originally developed with a single language in mind, the JVM is now targeted by numerous programming languages—its automatic memory management, just‐in‐time compilation, and adaptive optimizations—making it an attractive execution platform. However, the garbage collector, the just‐in‐time compiler, and other optimizations and heuristics were designed primarily with the performance of Java programs in mind. Consequently, many of the languages targeting the JVM, and especially the dynamically typed languages, are suffering from performance problems that cannot be simply solved at the JVM side. In this article, we aim to contribute to the understanding of the character of the workloads imposed on the JVM by both dynamically typed and statically typed JVM languages. To this end, we introduce a new set of dynamic metrics for workload characterization, along with an easy‐to‐use toolchain to collect the metrics. We apply the toolchain to applications written in six JVM languages (Java, Scala, Clojure, Jython, JRuby, and JavaScript) and discuss the findings. Given the recently identified importance of inlining for the performance of Scala programs, we also analyze the inlining behavior of the HotSpot JVM when executing bytecode originating from different JVM languages. As a result, we identify several traits in the non‐Java workloads that represent potential opportunities for optimization. © 2015 The Authors. Software: Practice and Experience Published by John Wiley & Sons Ltd. 相似文献
46.
47.
Shu Xia Tao Peter H.L. NottenRutger A. van Santen Antonius P.J. Jansen 《Journal of Alloys and Compounds》2011,509(2):210-216
Absorption energies of hydrogen in Mg0.75Ti0.25 alloys as a function of the hydrogen concentration were calculated using Density Functional Theory. Four types of structures of alloys and their hydrides including TiAl3, ZrAl3, AuCu3, and segregated types of structures were considered. The stability of the configurations, and the structural and electronic bonding properties were studied. The hydrogenation properties depend highly on the structure of the alloys. The ordered alloys have very similar properties to that of pure Mg. For segregated alloys, the hydrogenation properties can be divided to Ti-like, ordered alloy-like and Mg-like from low to high hydrogen concentration. The formation energies show that for the four structures, segregated Mg0.75Ti0.25 is favored for alloys, whereas TiAl3 type of Mg0.75Ti0.25H2 are favored for hydrides. Therefore hydrogen induced structural rearrangement of the intermetallic structures of the Mg0.75Ti0.25 might occur upon hydrogen cycling. For the non-homogenous Mg-Ti-H system, further phase segregation of Ti in Mg might occur. Partial dehydrogenation with some hydrogen remaining in the Ti-rich region may improve reversibility. 相似文献
48.
Julieta S. Riva Candelaria I. Cámara Ana V. Juarez Lidia M. Yudi 《Journal of Applied Electrochemistry》2014,44(12):1381-1392
The behaviours of several cationic polyelectrolytes (chitosan; polyquaternium-4; diethylaminoethyl dextran; polyquaternium-10, and aminoacrylmethacrylate copolymer, Eudragit® E100) at a polarised liquid/liquid interface are analysed and compared in the present paper. Based on the analysis of the voltammetric results, it was possible to determine some of the relationships between polymer structure and the tendency to adsorb at the interface. It was also possible to determine the substitution degree of a polymer comprising a chitosan main chain modified with glycidyltrimethylammonium chloride, and the values obtained are in agreement with those calculated using other methodologies. Finally, we report a comparative study concerning the effect of cationic (chitosan) and anionic (dextran sulphate) polyelectrolytes on the compactness of a phospholipid film. 相似文献
49.
Polyvinyl chloride paste blending resins were prepared by a suspension polymerization process, and the optimum ingredients and technological conditions were studied experimentally. The effect of dispersant, surfactant, and agitator design on the particle morphology was discussed. In order to improve the thermal stability of the blending resin, stabilizer was added to the polymerization system, and a special after-treatment was adopted. The effect of blending resins on the rheological and gelation characteristics of the plastisols formed and on mechanical properties, thermal stability, and foamability of the finished articles is demonstrated. 相似文献
50.
为探究纳微米微球调驱剂与葡北油田L区块的适应性,在纳微米微球深部调驱机理的基础上,开展了纳微米微球室内性能评价实验。结果表明,纳微米微球在油田回注污水中具有较好的分散性,其水化膨胀后的粒径中值满足对L区块地层的封堵要求。当纳微米微球质量浓度为2000mg/L时,水化膨胀效果最好,其水化膨胀30d后的膨胀倍率达到5.7。纳微米微球调驱实验使最终采收率提高了10%,说明纳微米微球可以对非均质地层中的高渗层进行封堵。 相似文献