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31.
32.
Total microbial count was not adversely affected by lowering the holding temperature of fabricated beef roast from 60°C to 54°C or by 12 hr holding time. If a reduction in holding temperature is anticipated, then initial roast contamination and sanitation of the food facility are of critical importance. A stabilizing period of 20 min at room temperature (~23°C) did not decrease yield, but caused a slight lowering of sensory scores. Tenderness was more acceptable in product held at 54°C compared to 60°C. In general, all sensory evaluation ratings were slightly lower with increased holding time.  相似文献   
33.
本文通过住宅区总体规划与环境设计,居住户型的多样化,美观大方的住宅立面设计,方便安全的停车场所四个方面谈了自己对住宅设计的认识与体会.  相似文献   
34.
Interactions between the yeast strain used for primary oenological fermentation and the bacterium used to conduct subsequent malolactic fermentation were studied under model winemaking conditions. A commercial Saccharomyces cerevisiae wine yeast (strains, EC 1118, AWRI 835 and CY-3079) was grown in a defined medium whose composition approximated grape juice. Fermentations by all strains reached dryness, and retained a cell viability of greater than 90% upon completion of fermentation. Highest total viable cell number and percentage of viable cells were recorded for EC 1118. A sur lie ageing of the fermented medium over a 12 week period revealed a bi-phasic decay of culture viability for all strains. Thus 99% of cells had died within 2 weeks post-fermentation. Viabilities were then stable for the subsequent 4–6 week period before a second decline phase ensued and ended in either a minimal ( ca 100 CFU/mL, EC 1118) or no viable cells being detected at 12 weeks of ageing. The growth response of an Oenococcus oeni inoculum to yeast culture supernatants, previously aged for up to 12 weeks in the presence or absence of yeast lees, was evaluated in a bio-assay. In this way, yeast strains could be designated as being either inhibitory, neutral or stimulatory to the growth of O. oeni (strain Lc5p). Inhibition by supernatants of strain EC 1118 was evident, but found to be reduced by ageing the supernatant (with or without lees). Conversely, longer ageing on yeast lees increased the magnitude of the stimulatory response in O. oeni (strain Lc5p) to the supernatant from the wine yeast (strain CY-3079).  相似文献   
35.
无线信道中的电波传播   总被引:2,自引:0,他引:2  
分析了信号在无线信道中传输时所经受的两种衰落,介绍了主要的无线传播模型,在此基础上提出了对抗衰落的措施。  相似文献   
36.
耐高温微生物驱油提高低渗透油藏采收率先导性试验   总被引:2,自引:1,他引:1  
胜利油田东辛高温低渗透油藏含蜡高,常温微生物无法存活,针对这一问题,引进美国NPC公司耐高温菌种,在Y6-16井组开展高温低渗油藏微生物驱油提高采收率研究和现场试验。施工后Y6-16井日增注52m3,表皮系数由施工前的2.069减小为施工后的-6.31,油层污染得到较好改善;原油含蜡量、胶质沥青质含量降低,轻质组分增加,重质组分降低;井组采收率提高5.09个百分点。  相似文献   
37.
Previous work on transmitter antenna diversity has shown that the use of multiple transmitter antennas at the base station results in improved performance due to increase of diversity (path diversity). This happens with no bandwidth cost, even when the signal quality along several paths is poor, but the receiver estimates the channel with accuracy. This paper evaluates the effects of channel estimation errors in the performance of the schemes designated as Space-Time Transmitter Diversity (STTD) and Selective Transmitter Diversity (STD). We consider low to medium signal to noise ratios characteristic of Wideband Code Division Multiple Access (WCDMA) networks. Different fading channel models are considered for comparison between the two schemes. The improvement due to convolutional coding associated with these techniques is also evaluated.  相似文献   
38.
Working collaboratively, psychologist educators and trainers at the doctoral, internship, and postdoctoral levels; credentialers; practitioners; and students offer 8 proposals for psychologists to consider in recognizing, assessing, and intervening with problems of professional competence in students and practicing professionals. In the proposals, the authors address the following topics: definitions and categories; preparing the system; self-assessment; remediation; diversity; communication across various levels of the system; confidentiality; and ethical, regulatory, and legal underpinnings. They also propose future directions for the assessment of problems in professional competence in both students and practicing psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
39.
施清  徐安士  谢麟振 《中国激光》1993,20(3):183-186
本文讨论了相干光纤通信系统中的偏振分集接收机的基本原理,并在实验中首次实现了基于偏振分集的偏振不敏感接收。在调制信号为137.2MHz和146.0MHz正弦波的情况下,得到了很好的与信号偏振面无关的解调信号。这一结果正在应用于1.5μm波段140Mb/s FSK相干光纤通信系统之中。  相似文献   
40.
多版本软件通过设计相异性实现了软件容错。为了对这种方法进行研究,我们的课题实现了一个三版本软件系统,称之为SFTMP(SoftwareFault-TolerantMultiProcessor)。本文描述了SFTMP的硬件结构和软件执行支持环境,该环境包括同步、表决和监控功能、版本间的通讯及故障的恢复和重构。  相似文献   
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