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41.
This communication gives an outline of a user-friendly PC wde developed for preliminary design of a fluid bed dryer (FBD) and its essential ancillaies e.g. cyclone, fan etc.. The fluid bed dryer may have internal heat exchangers. Correlations used for design calculations are presented. The program permits estimation of the energy consumption as well as the installed and operating costs. 相似文献
42.
This paper deals with studies on the dilute solution properties of methyl methacrylate—acrylonitrile copolymer of 0.289 mole fraction (mf) of acrylonitrile composition. Mark—Houwink parameters for this copolymer have been evaluated in acetonitrile (MeCN), 2-butanone (MEK), dimethylformamide (DMF) and γ-butyrolactone (γ-BL). The solvent power is found to be in the order of MEK < MeCN < DMF < γ-BL at 30°C. Herein, probably for the first time, the steric factor for the copolymer is found to be lower than that for the parent homopolymers and the excess interaction parameter, χAB is found to be negative. This probably suggests that the units are compatible to each other. 相似文献
43.
Rami A. Rihani Leonhard E. Bernold 《Computer-Aided Civil and Infrastructure Engineering》1994,9(1):61-67
Abstract: Computers are essential in the development of robotic systems for construction. The introduction of such systems creates many challenges to researchers, equipment manufacturers, and users alike. This paper presents a new initiative to study critical issues related to the establishment of a robotic masonry system. In particular, the paper discusses three major problem areas: (1) design automation, (2) automated mortar application, and (3) adaptive control of brick placement. The data presented have been generated using standard PC computers which control and integrate design tools with real-time machinery and sensory devices. 相似文献
44.
Abraham Warshawsky Avraham Patchornik Rami Kalir Sarah Ehrlich-Rogozinski 《Hydrometallurgy》1979,4(1):93-104
Polymeric pseudocrown ethers, incorporating oxyethylene and oxypropylene units, extract FeCl4? from mixed hydrochloric and phosphoric acids. The complexation depends on hydrochloric acid concentration and becomes efficient when the HCl concentration exceeds 4 M. The regeneration of the polymers is accomplished with water. Column tests have been shown to separate iron very efficiently from phosphoric acid, which is recovered quantitatively. In comparison, Amberlyst A-21, a weak-base anion exchanger, shows affinity for phosphoric acid, making the separation between iron and phosphorus difficult. 相似文献
45.
The relative amounts of freezing and nonfreezing water in various water-wet cellulose acetate (CA) membranes were determined by NMR techniques, from the initial heights of the water component in the free induction decay (MNR intensity). The results suggest that (1) a significant fraction of the water in various wet CA membranes does not freeze, probably because of strong interaction with the polymer; (2) the relaxation times T2 of the nonfreezing water are of the order of milliseconds indicating that they are still highly mobile compared with ice; (3) all the water contained in dense CA films or in membranes equilibrated at relative humidity of 0.93 does not freeze upon cooling the membranes from room temperature to ?60°C; (4) the amounts of nonfreezing bound water in membranes is higher than the total amount of water absorbed from liquid water by a dense film of the same polymer. However, the amounts of nonfreezing water in various CA membranes as calculated from the “relative NMR intensities” is substantially lower than those calculated from DSC melting endotherms by assuming the heat of fusion of water in membranes to be identical to that of pure water. Various possible reasons for this discrepancy are discussed. Measurements on the first desorption-adsorption cycle of wet CA membranes have also been performed. They suggest that during the first dehydration process, irreversible changes are induced in the structure of the membrane which result in a significantly lower accessibility of the polymer to interact with water. The extent of these irreversible changes in membrane structure is dependent on the details of the dehydration process being more pronounced at higher temperatures. 相似文献
46.
European Journal of Wood and Wood Products - Surface tension of solid wood surfaces affects the wettability and thus the adhesion of various adhesives and wood coatings. By measuring the contact... 相似文献
47.
Kumar A. Madhan Ehsan Muhammad Ali Suleiman Rami K. Hakeem Abbas Saeed 《Metallurgical and Materials Transactions A》2020,51(8):4301-4312
Metallurgical and Materials Transactions A - The surface of implant materials is one of the most significant factors for controlling the interaction between biomaterials and bone tissues. Hence,... 相似文献
48.
Networks and Spatial Economics - Advanced attackers use online social networks in order to extract useful information about targeted organizations, including the names of the organization’s... 相似文献
49.
Abdallah Mohamed Arab Mohamed Shabib Ahmad El-Sherbiny Rami El-Sheltawy Shakinaz 《Clean Technologies and Environmental Policy》2020,22(6):1371-1383
Clean Technologies and Environmental Policy - The aim of the present study was to establish a national database of waste characteristics for Egypt to support the assessment of various waste... 相似文献
50.
Alessandro Tocchio Naside Gozde Durmus Kaushik Sridhar Vigneshwaran Mani Bukre Coskun Rami El Assal Utkan Demirci 《Advanced materials (Deerfield Beach, Fla.)》2018,30(4)
In nature, cells self‐assemble at the microscale into complex functional configurations. This mechanism is increasingly exploited to assemble biofidelic biological systems in vitro. However, precise coding of 3D multicellular living materials is challenging due to their architectural complexity and spatiotemporal heterogeneity. Therefore, there is an unmet need for an effective assembly method with deterministic control on the biomanufacturing of functional living systems, which can be used to model physiological and pathological behavior. Here, a universal system is presented for 3D assembly and coding of cells into complex living architectures. In this system, a gadolinium‐based nonionic paramagnetic agent is used in conjunction with magnetic fields to levitate and assemble cells. Thus, living materials are fabricated with controlled geometry and organization and imaged in situ in real time, preserving viability and functional properties. The developed method provides an innovative direction to monitor and guide the reconfigurability of living materials temporally and spatially in 3D, which can enable the study of transient biological mechanisms. This platform offers broad applications in numerous fields, such as 3D bioprinting and bottom‐up tissue engineering, as well as drug discovery, developmental biology, neuroscience, and cancer research. 相似文献