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101.
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M.?S.?Miskandar Y.?B.?Che ManEmail author M.?S.?A.?Yusoff R.?Abdul Rahman 《Journal of the American Oil Chemists' Society》2002,79(12):1163-1168
Margarines made from refined, bleached, and deodorized palm oil at different emulsion temperatures showed no significant difference
in their consistency, polymorphic behavior, and solid fat content (SFC) during storage, although differences were observed
during processing. The emulsion temperatures studied were 40, 45, and 50°C, with other parameters such as emulsion flow rates,
tube cooler temperature, and pin rotor speed kept constant. The SFC developed during processing and storage at 28°C was measured
to evaluate the quality of margarine. The emulsion contained no SFC at any emulsion temperature studied. However, the amount
of SFC in the perfector or tube cooler unit increased to 15.9, 13.9, and 15.6% in margarine produced at emulsion temperatures
of 40, 45, and 50°C, respectively. At 40°C, the lowest SFC was developed during storage even though this margarine had the
highest consistency. The softening point of this sample was moderately high and closely related to the type of crystal developed,
which was a mixture of β′ and β crystals. Emulsion at 45°C gave the most stable margarine consistency and SFC with crystal
in the β′ form even after the fourth week. At 50°C, moderately soft product was produced, which might be undesirable for some
applications, although the crystals were in the β′ form. 相似文献
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Akio Takemura Yoshinori Shimizu Bunichiro Tomita Hiroshi Mizumachi 《The Journal of Adhesion》1992,37(1):161-172
Dynamic mechanical properties and adhesive strengths of power feed copolymer and random copolymer synthesized using styrene or methyl methacrylate and n-butyl acrylate were investigated. Although the two systems were synthesized from the same raw materials, power feed copolymer had a very broad transition compared with random copolymer. This fact was explained by the fact that the system synthesized through power feed method was an alloy of copolymers which are a continuous series from monomer A rich copolymers to monomer B rich copolymers. The dynamic mechanical behavior of film cast from solution was almost the same as that of emulsion film, which indicated more extensive application of power feed copolymer. In the P(nBA/St) system, power feed copolymer maintained its adhesive strengths over a wide temperature range compared with random copolymer. The absolute value, however, was not so high. This was due to the low cohesive strengths of the films. 相似文献
105.
汽—液—液三相与汽—液两相塔板效率比较 总被引:1,自引:0,他引:1
本文通过小型精馏塔及600×150 mm~2矩形模拟塔的实验,对比研究了气(汽)-液两相和气(汽)-液-液三相的塔板效率。并就物系性质(表面张力梯度、液体粘度或分散粘度),两液相体积比,气速及操作工况对传质的影响进行了研究。提出三相传质和两相传质差异的主要因素,得出估算三相精馏塔板效率的关联式。 相似文献
106.
借助电导率仪、光学显微镜和亚微粒子分析仪等测试手段。研究了乳液聚合导致一种新的转相过程,并用于八甲基环四硅氧烷的聚合中。研究表明:体系以 W/O 相态开始,单体由连续相向水相(分散相)内的胶束中扩散并发生聚合反应,形成 O/W/O 复合乳液。反应过程中连续相体积不断减小,分散相(O/W 复相)体积不断增大,当达到某一临界相比时,体系发生转相,转相后乳液为 O/W。对本实验物系,转相点临界相比主要由初始水油比和乳化剂浓度决定。同常规的乳液聚合相比,伴有转相现象的乳液聚合有其自身的特点,转相使得聚合速率、聚合物粒径及分布、乳液稳定性等发生变化。 相似文献
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110.
Charles David Immanuel 《Chemical engineering science》2003,58(16):3681-3698
A computationally efficient solution technique is presented for population balance models accounting for nucleation, growth and coagulation (aggregation) (with extensions for breakage). In contrast to earlier techniques, this technique is not based on approximating the population balance equation, but is based on employing individual rates of nucleation, growth and coagulation to update the PSD in a hierarchical framework. The method is comprised of two steps. The first step is the calculation of the rates of nucleation, growth and coagulation by solving an appropriate system of equations. This information is then used in the second step to update the PSD. The method effectively decomposes the fast and the slow kinetics, thereby eliminating the stiffness in the solution. In solving the coagulation kernel, a semi-analytical solution strategy is adapted, which substantially reduces the computational requirement, but also ensures the consistency of properties such as the number and mass of particles. 相似文献