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951.
Sulaiman Al‐Zuhair Kadathur B Ramachandran Masitah Hasan 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(7):706-710
Oil–water dispersions have many important applications in the chemical and oleochemical industries. A measure of the specific interfacial area of the dispersed phase provides a direct indication of the quality of the dispersion. In this study, the specific interfacial area for the palm oil–water system was determined using a microscopic technique. The effects of oil volume fraction, agitation speed and temperature on the specific interfacial area have been determined experimentally and an empirical correlation to predict the total specific interfacial area under different operating conditions is proposed. This correlation can be used in the design of reaction and non‐reaction systems using palm oil–water dispersions. Copyright © 2004 Society of Chemical Industry 相似文献
952.
The light attenuation technique has been modified to expand the range of its applicability up to AL values of 460. This has been accomplished through the use of a laser as the source of monochromatic collimated light, and a very sensitive low-bias picoammeter. The data obtained using the photographic technique were found to agree reasonably well with those from light attenuation. 相似文献
953.
Dams are used for recharge purposes in many parts of Saudi Arabia. In spite of the importance of such a method, no detailed study exists on its performance. As a part of a comprehensive research project dealing with all aspects of dams as a recharge tool in the central region of the country, data on reservoirs’ water levels, meteorological parameters and observation wells were collected at two recharge dam sites. These data were used in a water budget approach to estimate efficiency. Contrary to the established belief that this method of recharge is poor, results show that between 82% and 94.5% of water stored in the two reservoirs was taken into the soil. 相似文献
954.
Liquid/liquid dispersion in static mixers has been investigated using Lightnin “In-liner” mixing elements. The average drop size was found to decrease with increasing residence time, gradually approaching an equilibrium size whose magnitude agrees reasonably well with Kolmogoroff's theory for drop rupture in turbulent flows. The efficiency at which mechanical energy is utilized in the generation of new interfacial area was evaluated as a function of design and operating conditions and was found to be highest when the final drop size is much larger than the achievable equilibrium value. 相似文献
955.
An accelerated method for evaluating the compaction behavior of dense suspensions is presented, in which centrifugal force is used to enhance settling rates and a highly-compensated compound pendulum is used to detect the resultant small shifts in centre of gravity. The results obtained by following the temporal variation in suspension characteristics indicate that a Richardson and Zaki type of equation can describe the subsidence of very concentrated suspensions. The exponent n, and the ultimate sediment compaction density were found to be strongly influenced by small changes in the physicochemical characteristics of the suspended solids. 相似文献
956.
首次提出了一种实现超大卢、阵光束分束的新方法,它是利用位相迭加原理和VLSI技术将光栅分束器和位相型菲涅耳微透镜列阵集成为一体,构成了一种新型的光束分束列阵器件—一菲涅耳计算机源生全息分来器(CGFBS),以实现128×128,甚至更高卢、阵数的光点分束。 相似文献
957.
Al. G. Shalimov 《Metallurgist》2005,49(1-2):32-38
A recent seminar explored new innovations in metallurgical technology and provided a forum for discussing how companies and research organizations manage and plan activities in this area. Two of the specific cases examined were the work done by the Moscow Institute of Steel and Alloys to find new ways to develop the Udokan copper deposit and the efforts of the institute Stal’proekt to provide engineering-technical support to companies interested in modernizing their furnaces. Among the other topics covered were technical consulting on the use of technogenic materials, the recycling of such materials by the Romelt process, an energy-saving method of producing cast iron and ferroalloys in a new type of furnace — an oxygen reactor — and the development and introduction of automated production units in metallurgy. Reports were also given on new high-strength corrosion-resistant steels, the possible use of new protective coatings on steel plates and tubes, and aspects of micro-metallurgy.Translated from Metallurg, No. 1, pp. 45–49, January, 2005. 相似文献
958.
Questions concerning the compensation of excess reactivity in pressurized-water reactors by using consumable granular absorbers
are examined. A method of computing the spatial-energy distribution of the neutrons in cells with a granular absorber is presented.
The neutron-physical and thermophysical characteristics of fuel assemblies with fuel elements based on homogenized and heterogeneous
arrangements of gadolinium in them are compared. It is shown that granular absorbers have certain advantages, specifically,
they decrease the gadolinium content in the fuel elements and at the same time increase the total number of gadolinium-containing
fuel elements in the fuel assemblies. This decreases the maximum power released in the gadolinium-containing fuel elements
and the temperature of the fuel during the entire run.
__________
Translated from Atomnaya énergiya, Vol. 100, No. 1, pp. 8–13, January, 2006. 相似文献
959.
Omaimah M.N. Al Gohary Seham S. Abd El Hady Nabila A. Daabis 《Drug development and industrial pharmacy》1991,17(15):2055-2065
In this study Eudragit RS PM and RL PM were evaluated as carriers for the preparation of prolonged release solid dispersions of mebeverine hydrochloride by solvent and melting methods. The prepared tablets were examined for dissolution at pH 1.2 and 7.4, Eudragit RS PM and RL PM were found satisfactory as potential slow release carriers. The solid dispersion prepared by the solvent method showed a slow release pattern. Drug release appeared to fit both, first order and Higuchi matrix model kinetics. However, on application of the differential rate treatments, the evidence supported the Higuchi matrix model. Effect of temperatures on dissolution rate was studied for thermodynamic consideration.
The drug release was pH-independent until pH 7.4.As the pH increased, the release was significantly reduced due to solubility problem. 相似文献
The drug release was pH-independent until pH 7.4.As the pH increased, the release was significantly reduced due to solubility problem. 相似文献
960.
Benzaid Mounir Minet Pascale Al Agha Khaldoun Adjih Cedric Allard Geraud 《Wireless Networks》2004,10(4):377-388
Trends in fourth generation (4G) wireless networks are clearly identified by the full-IP concept where all traffic (data, control, voice and video services, etc.) will be transported in IP packets. Many proposals are being made to enhance IP with the functionalities necessary to manage the mobility of nodes, so that networks can provide global seamless roaming between heterogeneous wireless and wired networks. In this paper, we focus on the management of universal mobility, including both large scale macro-mobility and local scale micro-mobility. We propose a hierachical architecture (i) extending micro-mobility management of a wireless access network to an ad-hoc access network, (ii) connecting this ad-hoc network to the Internet and (iii) integrating Mobile IP and OLSR, a routing protocol for ad-hoc networks, to manage universal mobility. This architecture is validated by an implementation based on DynamicsMobile-IP and OLSR version 7. We show how the brodcast of Mobile-IP Agent Advertisement can be optimized using OLSR MPR-flooding. 相似文献