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61.
通过常温下不同储藏方式的谷糙对照储藏试验表明;稻谷与糙米的储藏品质变化和粮情变化因储藏方式不同差异明显,而相同储藏方式与储藏条件下的稻谷糙米之间却差异较小.常温下的早籼稻谷,当水分在安全标准(13%)以内时,其糙米双低储藏与常规储藏是可行的.  相似文献   
62.
欧美汽车用润滑脂现状   总被引:1,自引:0,他引:1  
列举了国外比较有代表性的润滑脂供应商的14种车用润滑脂产品和3个指标规范,通过分析,总结 欧洲和美国车用润滑脂产品的现状和特点,找出了我国车用润滑脂和国际先进水平的差距和不足。  相似文献   
63.
微生物油脂主要是微生物利用碳水化合物合成的甘油酯,其脂肪酸组成和植物油相近,有的还含有较丰富的多不饱和脂肪酸,具有广阔的开发应用前景。介绍了从微生物油脂中分离纯化具有功能性的多不饱和脂肪酸的方法,继而阐述了以微生物油脂为原料,甲醇作酯交换剂,在催化剂的作用下制备生物柴油的方法和技术。同时对微生物柴油的可行性进行了分析。  相似文献   
64.
李松生  黄晓  李东烥  周鹏  陈斌 《轴承》2011,(11):30-33
针对脂润滑的混合陶瓷球高速主轴轴承的工作特点,对不同工况下的混合陶瓷球高速主轴轴承进行了早期失效试验,并对其早期失效的原因进行了分析研究。结果表明,高速条件下脂润滑的混合陶瓷球主轴轴承发生早期失效的原因主要是高速运行和快速频繁启停而产生的剧烈冲击、摩擦和较高的工作温度所导致的保持架薄弱部位断裂,其运行时间远未达到轴承寿命理论所预期的疲劳寿命或精度寿命。  相似文献   
65.
Lysophosphatidic acid (lysoPtdOH) levels have previously been reported to decrease in rodents with short-term fasting. We investigated whether a 16 h fast would change expression of autotaxin, the predominant phospholipase D responsible for adipose-derived lysoPtdOH synthesis, or any of the lysophosphatidic acid receptors (1–6) in four white adipose tissue (WAT) depots and interscapular brown adipose tissue (BAT) in male C57Bl/6J mice fed ad libitum, or fasted for 16 h. Aside from small inductions of Lpar1 in epididymal WAT and Lpar2 in epididymal and inguinal WAT, no significant changes were observed in expression of the Lpar family members, or autotaxin in perirenal, retroperitoneal, epididymal, or inguinal WAT or BAT with fasting. Comparison of the relative expression of Lpar1-6 in various depots showed that Lpar6 was the predominant Lpar in both WAT and BAT, and suggests that further work on the adipose-specific role of Lpar6 is warranted.  相似文献   
66.
利用MQ - 800型四球摩擦磨损试验机考察了纳米二硫化钼和微米二硫化钼在聚-α-烯烃润滑脂中的摩擦学性能.结果表明纳米二硫化钼的减摩抗磨性能优于微米二硫化钼.这是因为纳米二硫化钼在摩擦表面形成了吸附膜,提高了润滑脂的减摩抗磨性能.  相似文献   
67.
Architecture is on the cusp of systemic change, driven by the dynamics of climate and economy, of new technologies and new means of production. There is a growing interest in the dynamics of fluidity, in networks and in the new topologies of surfaces and soft boundaries. This is part of a general cultural response to the contemporary reconfiguration of the concept of ‘nature’ within the discourse of architecture; a change from metaphor to model, from ‘nature’ as a source of formal inspiration to ‘nature’ as a mine of interrelated dynamic processes that are available for analysis and digital simulation. Michael Weinstock presents an account of the dynamics of natural metabolisms, and suggests an agenda for the development of metabolic morphologies of buildings and cities. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
68.
The accuracy of genomic prediction determines response to selection. It has been hypothesized that accuracy of genomic breeding values can be increased by a higher density of variants. We used imputed whole-genome sequence data and various single nucleotide polymorphism (SNP) selection criteria to estimate genomic breeding values in Brown Swiss cattle. The extreme scenarios were 50K SNP chip data and whole-genome sequence data with intermediate scenarios using linkage disequilibrium-pruned whole-genome sequence variants, only variants predicted to be missense, or the top 50K variants from genome-wide association studies. We estimated genomic breeding values for 3 traits (somatic cell score, nonreturn rate in heifers, and stature) and found differences in accuracy levels between traits. However, among different SNP sets, accuracy was very similar. In our analyses, sequence data led to a marginal increase in accuracy for 1 trait and was lower than 50K for the other traits. We concluded that the inclusion of imputed whole-genome sequence data does not lead to increased accuracy of genomic prediction with the methods.  相似文献   
69.
对利用γ射线透射幅度谱测管道油垢厚度响应的宽束影响进行了研究。模拟实验装置由137Cs γ射线的准直束、NaI(TI)探测器和BH1224多道谱仪组成。实验结果表明:响应与油垢厚度呈线性关系。利用光电峰区测垢,标定直线的斜率为负值;利用康普顿峰区测垢受宽束的影响,其标定直线的斜率为正值,但随管道直径增大斜率迅速减小。利用全谱测垢,对于细管道斜率为正值,对于粗管道则为负值。实测的修正因子β与1的偏差均<2%。  相似文献   
70.
The brown pigment in sautéed onion was characterized by a microbiological procedure (involving microbial decolorization) and a chemical procedure (involving metal-chelating chromatography with a Sepharose 6B column). The suitability of the chemical procedure as a method for classifying brown pigments was also examined.The pigment from sautéed onion was about 40% decolorized by Coriolus versicolor IFO 30340, as were the model pigments caramel and model melanoidin (MM). The phenol-type model pigments (PTMP) were approximately 40-60% decolorized by Paecilomyces canadensis NC-1, but the sautéed-onion pigment, the MM and the caramel were merely 5% decolorized by it. The pigment from sautéed onion was separated into two components by Cu2+, Fe2+, or Zn2+-chelating chromatography, as were caramel and MM; the PTMP was not separated into multiple components by either Cu2+ or Fe2+-chelating chromatography. The results from both methods indicate that the pigment from sautéed onion is similar to MM and caramel but not the phenol-type pigment.  相似文献   
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