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991.
992.
Singular and combined effects of added water, sodium erythorbate and storage time on salt soluble protein extractability, bacteriological and chemical characteristics of preblended hot-boned beef were evaluated. Waterholding and gel forming capacities of preblended hot-boned beef containing either 0, 10 or 20% added water were determined. Significant interactions between added water level and storage time on microbial counts and between sodium erythorbate level and storage time on thiobarbituric acid values and residual nitrite levels were noted. The presence of sodium erythorbate resulted in a more (P < 0·05) rapid rate of nitrite disappearance, but it did not affect (P > 0·05) microbial counts. Salt-soluble protein extractability was not affected (P > 0·05) by added water, but more protein could be extracted with increasing storage time. A trend existed to suggest that the presence of added water in the meat preblends slightly improved the gel formation and waterholding capacities. 相似文献
993.
Comparisons were made of the effect on cooling rate, weight loss, texture, bacterial numbers, drip and appearance of pork sides (average dead weight 75 kg) in refrigeration systems using high humidity (ice bank) or conventional chilling, both with and without a rapid pre-chill or delayed chilling, with and without a water spray. All treatments took between 15·7 and 19h post mortem to cool the deep leg of sides to 7°C. Weight loss varied between 0·95% for sides in the delay and spray treatment to 2·17% for conventional chilling. The texture of the M. longissimus dorsi of sides from the rapid pre-chill and conventional chilling treatment was significantly tougher than from the other methods, including those from the rapid pre-chill and high humidity system. Variation in texture between animals within treatments was far greater than between treatments, and could not be explained by variations in cooling and glycolytic rate. There were no significant differences (P > 0·05) in bacterial numbers, drip and appearance between treatments. The choice of chilling system can be made on the basis of weight loss and capital and running costs. The delay and spray treatment would save £37 800 on an annual throughout of 3 080 tonnes of pork compared with a conventional system. 相似文献
994.
The ability of Lactobacillus jensenii and Streptococcus 17SB to inbhibit Escherichia coli was demonstrated. The practical application of the inhibition was examined. Possible roles for several factors in the mechanism of inhibition by Lactobacillus jensenii and Streptococcus 17SB are briefly discussed. The effects of pH reached and acids produced by starters on the growth of Escherichia coli are described. 相似文献
995.
Richard A.Quinnel 《电子设计技术》1995,(2)
网络行业正在开发100兆位的以太网络以满足局域网(LAN)容量日益增长的要求。为此,目前出现了两个标准,而每个标准却反映了不同的成本和权能交易。 相似文献
996.
人们面对面交谈与通过电话讲话所听到的话音之间有很大差异。典型的例子就是无线电调频广播中,听众通过电话与电台节目主持人的对话。这种音质上的差异要求我们研制从普通电话话音中产生宽带话音的算法。此算法有两个特点:一个是基于代码簿映像的频谱包络重建;另一个是采用以重建谱包络表示话音波形的话音信号重建。由于此算法无需任何附加的传输信息就能产生高质量话音,所以它在话音编码领域中十分重要且有用。以声距标准和收听测试来评估,证实此算法性能良好。 相似文献
997.
998.
Undoped and doped KCl single crystals have been successfully elaborated via the Czochralski(Cz) method.The effects of dopant Sb2O3 nanocrystals on structural and optical properties were investigated by a number of techniques,including X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray(EDAX) analysis,UV-visible and photoluminescence(PL) spectrophotometers.An XRD pattern of KCl:Sb2O3 reveals that the Sb2O3 nanocrystals are in the well-crystalline orthorhombic phase.The broadening of diffraction peaks indicated the presence of a Sb2O3 semiconductor in the nanometer size regime.The shift of absorption and PL peaks is observed near 334 nm and 360 nm respectively due to the quantum confinement effect in Sb2O3 nanocrystals.Particle sizes calculated from XRD studies agree fairly well with those estimated from optical studies.An SEM image of the surface KCl:Sb2O3 single crystal shows large quasi-spherical of Sb2O3 crystallites scattered on the surface.The elemental analysis from EDAX demonstrates that the KCl:Sb2O3 single crystal is slightly rich in oxygen and a source of excessive quantities of oxygen is discussed. 相似文献
999.
随着互联网技术的不断发展,互联网金融第三方支付平台得到了快速发展,给人们支付方式带来了巨大的影响.文章阐述了我国第三方支付的发展现状,并以支付宝为例展示了第三方支付平台发展模式,分析了互联网金融第三方支付在资金流动中存在的市场性风险、流动性风险、信用性风险、技术性风险,探讨了以上四种风险传导路径,并针对第三方支付风险提... 相似文献
1000.
溶剂性质对六硝基六氮杂异伍兹烷晶型的作用 总被引:5,自引:0,他引:5
研究稳定地得到e型六硝基六氮杂异伍兹烷( HNIW)的结晶工艺条件,并寻求多晶转变的理论解释。研究发现,非溶剂的物理性质,如偶极矩、分子极性,在结晶过程中对于HNIW的晶型起重要作用。常温下在无晶种时,当利用乙酸乙酯、丙酮作为溶剂,采用偶极矩值小的非溶剂,如环己烷、石油醚、甲苯、异辛烷等均可使HNIW以ε型晶型结晶出来,反之,采用偶极矩值大的非溶剂,如三甘醇则使HNIW以其它晶型结晶出来。在较高温度下,s型HNIW在极性与非极性溶剂中稳定存在时间明显不同。 相似文献