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91.
Isothermal crystallization of plam oil was studied by means of differential scanning calorimetry (DSC) as well as by nuclear
magnetic resonance spectrometry to monitor its solid fat content (SFC). The temperature of crystallization (Tc) varied from
0 to 30°C, depending on the method used. The plot of %SFC vs. time at 25°C was sigmoidal in shape. However, at lower temperatures,
two consecutive curves were clearly visible. Results from DSC experiments showed the following interesting features. At each
Tc, the crystals produced were of different compositions. From 0 to 8°C, the thermogram showed three peaks, with the first
two peaks (I and II) sharp, and the third (III) rather broad. At elevated temperatures up to 20°C, peak II disappeared totally
while peak III tended to shift toward peak I. Above 20°C, both peaks shifted downward to longer times. Peak I continued to
be broadened, and then suddenly disappeared at Tc above 24°C. The melting thermograms of the crystals obtained above and below
this cut-off point were distinctly different. Kinetic studies on isothermal crystallization based on the data of SFC measurements
showed that the data fit well into the Avrami-Erofeev equation with n=3 over the first 70% of the crystallization. 相似文献
92.
人类聚居环境学对于居住区规划设计的启示 总被引:1,自引:0,他引:1
以人类聚居环境学的研究方法从若干方面对目前的居住区规划设计进行了一定的探讨,分析规划设计及建设方面目前存在的主要问题,提出以人类聚居环境学为指导的居住区规划设计理念。 相似文献
93.
This study was carried out to determine the physical, chemical, microbiological and organoleptic properties of koumiss made from bovine milk. The bovine milk was modified according to the composition of mares’ milk using ultrafiltration, microfiltration and nanofiltration. Koumiss made from modified bovine milk and mares’ milk were compared. In order to assess options for a consistent fermentation, a starter culture, instead of the prevailing spontaneous flora in traditional manufacture of koumiss, was used. Key compositional factors modified were the contents of dry matter, mineral, protein and lactose and the casein-to-whey protein ratio. Koumiss made from modified bovine milk and by starter cultures was found to be very similar to koumiss from mares’ milk in terms of pH, titratable acidity, alcohol, proteolytic activity, apparent viscosity, and microbiological composition, when assessed both in the freshly made product and that after 15 days storage at 4°C. 相似文献
94.
95.
刘永增 《石油化工管理干部学院学报》2003,(2):58-59
阐述了人力资源管理在企业发展中的重要作用;对如何引入竞争机制、知人善任、建立科学的激励机制和约束机制、改革管理体制等方面进行了论述。 相似文献
96.
人的因素在家具质量管理工作中有着举足轻重的作用,各个层次的工作者有着不同的质量职责,发挥不同的作用。本文立足人的因素来解析企业质量管理体系中各层工作者的质量工作,及对质量管理体系运行的作用。 相似文献
97.
Mihir Bellare Adriana Palacio 《Applicable Algebra in Engineering, Communication and Computing》2006,16(6):379-396
Key-insulated encryption schemes use a combination of key splitting and key evolution to protect against key exposure. Existing
schemes, however scale poorly, having cost proportional to the number t of time periods that may be compromised by the adversary, and thus are practical only for small values of t. Yet in practice t might be large.
This paper presents a strongly key-insulated encryption scheme with optimal threshold. In our scheme, t need not be known in advance and can be as large as one less than the total number of periods, yet the cost of the scheme
is not impacted. This brings key-insulated encryption closer to practice. Our scheme is based on the Boneh-Franklin identity-based
encryption (IBE) scheme [9], and exploits algebraic properties of the latter.
Another contribution of this paper is to show that (not strongly) key-insulated encryption with optimal threshold and allowing
random-access key updates (which our scheme and all others known allow) is equivalent to a restricted form of IBE. This means
that the connection between key-insulated encryption and IBE is not accidental.
Supported in part by NSF grants CCR-0098123, ANR-0129617 and CCR-0208842, and by an IBM Faculty Partnership Development Award.
Supported in part by an NSF graduate fellowship. 相似文献
98.
田葵 《河南机电高等专科学校学报》2004,12(6):89-90
《聊斋志异》中的《青娥》一篇充满了浓郁的童话色彩,贯穿主人公爱情生活的始终是纯洁执着的赤子情怀,爱情充满了青春的芬芳和清新的童趣,而波折和迂回中始终不离主人公的至情和至孝。 相似文献
99.
100.