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931.
Processing of lipoxygenase-free soybeans and evaluation in foods 总被引:2,自引:2,他引:0
J. M. King S. M. Chin L. K. Svendsen C. A. Reitmeier L. A. Johnson W. R. Fehr 《Journal of the American Oil Chemists' Society》2001,78(4):353-360
Lipoxygenase-free soybeans were processed into flour, concentrate, and isolate and compared to normal soybeans in bread, meat
patties, and a beverage, respectively. Bread made with 20% normal or lipoxygenase-free soy flour had greater (P< 0.05) beany flavor than control yeast bread. There were no differences in beany flavor scores between soy flour types, normal
and lipoxygenase-free. Ground beef patties made with 5% acid-washed or ethanol-washed soy protein concentrate had greater
(P<0.05) beany flavor than control ground beef patties. Ground beef patties made with ethanol-washed concentrate were scored
lower in beany flavor than those made with acid-washed concentrate from normal soybeans. There were no differences in beany
flavor between normal and lipoxygenase-free soy isolate in 2%-fat or no-fat beverages. Comminuted meat products made with
lipoxygenase-free soy proteins, especially ethanol-washed concentrate, have potential for making soy foods with less beany
flavor than foods made with normal soy. 相似文献
932.
Experimental kinetic data are reported for key side reactions occurring in the front end [i. e. the reaction furnace (RF) and the waste heat boiler (WHB)] of modified Claus plants used for sulfur recovery from the sour gases evolved in the treatment of natural gas. An extensive experimental study was conducted in a high temperature tubular reactor system for two important homogenous gas‐phase reactions. Firstly, experiments were carried out to study the oxidation of hydrogen sulfide and methane mixtures in the presence of oxygen. Secondly, the reaction between methane and sulfur dioxide was investigated experimentally. These results showed that methane was much less competitive for oxygen than hydrogen sulfide. Hence, in a partially oxidizing environment of a RF, data showed that methane reacted significantly with other major sulfur containing species, as secondary reactions, to form COS and especially CS2. This is highly problematic from an environmental point of view. 相似文献
933.
Chin W.H. Farhang-Boroujeny B. 《Vision, Image and Signal Processing, IEE Proceedings -》2001,148(4):283-288
Adaptive filtering in subbands was originally proposed to overcome the limitations of conventional least-mean-square (LMS) algorithms. In general, subband adaptive filters offer computational savings, as well as faster convergence over the conventional LMS algorithm. However, improvements to current subband adaptive filters could be further enhanced by a more elegant choice of their design/structure. Classical subband adaptive filters employ DFT-based analysis and synthesis filter banks which results in subband signals that are complex-valued. The authors modify the structure of subband adaptive filters by using single-sideband (SSB) modulated analysis and synthesis filter banks, which result in subband signals that are real-valued. This simplifies the realisation of subband adaptive filters 相似文献
934.
Downlink beamforming is a promising technique for direct-sequence code-division multiple-access (DS-CDMA) systems with multimedia services to effectively reduce strong interference induced by high data rate users. A new downlink beamforming technique is proposed that converts the downlink beamforming problem into a virtual uplink one and takes into account the data rate information of all users. Since the main complexity of this method is due to the existence of multidelay paths, two simplified algorithms are suggested using an equivalent one-path channel vector to replace multipath channel vectors. Computer simulation results are given to evaluate the downlink capacity of DS-CDMA systems using a base station antenna array and the new algorithms proposed 相似文献
935.
通过对一株粪产碱杆菌WX-C12(Alcaligenes 相似文献
936.
Zhan Yu Tjeng Thiang Tjhung Chin Choy Chai 《Communications, IEEE Transactions on》2001,49(11):2006-2015
We derive exact expressions of the symbol error rate (SER) performance of orthogonal, frequency-hopped, noncoherent M-ary frequency-shift-keying (FH/MFSK) receivers in the presence of independent multitone jamming (MTJ), as well as thermal and other wideband Gaussian noises. Both the signal tones and the multiple jamming tones are affected independently by Rician fading. Both the slow-hopping and fast-hopping systems are considered. In our derivation, we exploit the fact that the multipath components of the signal and jamming tones can be combined with the other Gaussian noises to form a single Gaussian process. Using this technique, we are able to obtain compact exact SER expressions which can be computed efficiently. From the computation results we provide physical explanations on the effects of several system parameters, such as jamming fraction, fading conditions and number of hops per symbol, on the SER performance of slow and fast FH/MFSK systems under independent MTJ 相似文献
937.
Pilot symbol-assisted adaptive algorithms provide coherent detection for communication systems when the filtering coefficients, such as beamforming weights or equalizer coefficients, are converged. This property can be exploited to speed up the convergence of adaptive algorithms used. In this letter, two new adaptive algorithms, coherent least mean square (C-LMS) and coherent normalized LMS (CN-LMS), are proposed by constraining the desired signal component of the filtering output to be always coherent in phase with the reference signal at each iteration. For same adaption step size, these new algorithms provide faster convergence, while yield same steady-state excess mean-square error as compared with their standard LMS counterparts 相似文献
938.
Existing tree construction mechanisms are classified into source‐based trees and center‐based trees. The source‐based trees produce a source‐rooted tree with a low delay. However, for the applications with multiple senders, the management overheads for routing tables and resource reservations are too high. The center‐based trees are easy to implement and manage, but a priori configuration of candidate center nodes is required, and the optimization nature such as tree cost and delay is not considered. In this paper, we propose a new multicast tree building algorithm. The proposed algorithm basically builds a non‐center based shared tree. In particular, any center node is not pre‐configured. In the proposed algorithm, a multicast node among current tree nodes is suitably assigned to each incoming user. Such a node is selected in a fashion that tree cost and the maximum end‐to‐end delay on the tree are jointly minimized. The existing and proposed algorithms are compared by experiments. In the simulation results, it is shown that the proposed algorithm approximately provides the cost saving of 30 % and the delay saving of 10 %, compared to the existing approaches. In conclusion, we see that the cost and delay aspects for multicast trees can be improved at the cost of additional computations. 相似文献
939.
在常用的分光光度法基础上对超浓缩洗衣粉中磷酸盐进行定量测试研究。采用条件试验法进行了标准溶液吸取量、显色剂加入顺序、显色剂加入量、选取分析试样的探索,用正交试验法对试样称取量、加入的HNO3量、煮沸时间、试液吸取量等各种因素进行优选,探索出了适用于超浓缩洗衣粉中磷酸盐的定量分析方法,准确率达99%以上。 相似文献
940.
Self-Compensated Heterodyne Laser Interferometer 总被引:5,自引:1,他引:4
C. S. Chin B. K. A. Ngoi 《The International Journal of Advanced Manufacturing Technology》2000,16(3):217-219
The heterodyne laser interferometer has gained popularity in applications as an encoder system in ultra-precision machines.
It can provide ultra high resolution, which satisfies the requirements of ultra-precision machines. The difficulty of using
a laser interferometer is the elimination of the effects of change of the refractive index of air whether by variation in
environmental conditions or by external effects like air movement, air vibration and mechanical vibration. This paper presents
a new technique for the elimination of the effect of refractive index when using a heterodyne laser interferometer. The preliminary
results showed that this set-up has a better static error when compared to an industrial laser system. 相似文献