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81.
The selective separation of cobalt from acidic media, containing both equimolar and nonequimolar mixtures of cobalt and nickel, was examined by supported liquid membranes using Alamine 336 as mobile carrier dissolved in various diluents. The membrane support was microporous hydrophobic polypropylene Celgard 2500 (25 μm thick, 0.209 × 0.054 μm pore size and 55% porosity). Acetic acid-Na acetate buffer was used for the adjustment of the feed pH which was critical. Various parameters were experimentally studied and the optimum conditions were determined. 相似文献
82.
Hakimah Osman 《Polymer-Plastics Technology and Engineering》2013,52(3):243-250
Composites containing various percentage of durian seed flour (DSF) in the polypropylene (PP) and high density polyethylene (HDPE) have been compounded using an internal mixer. The processing torque, tensile, thermal and biodegradation properties have been determined. The incorporation of DSF increases stabilization torque and had adversely affected the mechanical properties by reducing the tensile strength and elongation at break, while the elastic modulus is increased, as starch content increases. At similar filler content, DSF filled PP showed higher tensile strength and elastic modulus, while lower in elongation at break than DSF-filled HDPE. The scanning electron microscopy (SEM) of tensile fracture specimens revealed good adhesion and dispersion of the DSF granules in the polymer matrix. However, the SEM results showed agglomeration of the DSF at higher filler content in the polymer and hence revealed poor wetting between DSF granules and polymer. The TGA results showed that both of the composites systems with higher filler content have higher initial degradation temperatures, T0, degradation temperatures, Tdeg and total weight loss. A simple biodegradability test conducted on each composite system shows that composites are subjected to biodegradation, judging by the significant increase in carbonyl and hydroxyl index of the composites after the test. 相似文献
83.
The reaction of glutaric anhydride with benzene and toluene has been thoroughly studied. 4,4-Diphenyl-pent-4-enoic acid and 1,3-dibenzoyl propane were isolated as by-products of the reaction with benzene. The mechanism of formation of the by-products has been proved. In case of toluene no by-products were detected. 相似文献
84.
The heat transfer characteristics of the flow around rectangular cylinders having various aspect ratios with uniform injection or suction through the rear, top, bottom, and all surfaces have been studied numerically. The effects of injection or suction on heat transfer have been linked to the analysis via wall functions of the velocity and temperature sublayers. The computational code employed in the present study was verified with a typical benchmark problem of the flow around a square cylinder. The results show that the heat transfer between the main flow and rectangular cylinders is substantially influenced by injection or suction—that is, suction enhances the heat transfer, while injection through the rear surface provides some thermal protection. 相似文献
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Osman Augustine; Kopper Beverly A.; Linehan Marsha M.; Barrios Francisco X.; Gutierrez Peter M.; Bagge Courtney L. 《Canadian Metallurgical Quarterly》1999,11(2):115
This study investigated the factor structure of the Adult Suicidal Ideation Questionnaire (ASIQ) and the Linehan Reasons for Living Inventory (LRFI) in a sample of 205 adult psychiatric inpatients. Confirmatory factor analyses provided moderate support for the construct validity of each instrument. Coefficient alphas for the ASIQ (.98) and LRFL (.93) were high. In addition, a range of different clinical cutoff points was derived for each instrument. Both instruments were also better than chance in differentiating between the suicide attempter and psychiatric control groups. High ASIQ and low LRFL scores were significantly associated with scores on selected Minnesota Multiphasic Personality Inventory-2 Content scales. The analyses also indicated that only the ASIQ added to the symptoms of hopelessness and negative affect in differentiating between the suicide attempter and psychiatric control groups. Results suggest that both instruments may be useful screening tests for suicidal behavior in psychiatric long-term care inpatient samples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
In this paper, a supervised algorithm for the evaluation of geophysical sites using a multi‐level cellular neural network (ML‐CNN) is introduced, developed, and applied to real data. ML‐CNN is a stochastic image processing technique based on template optimization using neighborhood relationships of the pixels. The separation/enhancement and border detection performance of the proposed method is evaluated by various interesting real applications. A genetic algorithm is used in the optimization of CNN templates. The first application is concerned with the separation of potential field data of the Dumluca chromite region, which is one of the rich reserves of Turkey; in this context, the classical approach to the gravity anomaly separation method is one of the main problems in geophysics. The other application is the border detection of archeological ruins of the Hittite Empire in Turkey. The Hittite civilization sites located at the Sivas‐Altinyayla region of Turkey are among the most important archeological sites in history, one reason among others being that written documentation was first produced by this civilization. 相似文献
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90.
This paper provides a continuation of ideas presented by Davvaz and Mahdavipour [B. Davvaz, M. Mahdavipour, Roughness in modules, Inform. Sci. 176 (2006) 3658-3674]. The notion of hypermodule is a generalization of the notion of module. In this paper, we consider the quotient hypermodule M/A and interpret the lower and upper approximations as subsets of the quotient hypermodule M/A. Then, we introduce the concept of quotient rough sub-hypermodule. Also, using the concept of fuzzy sets, we introduce and discuss the concept of fuzzy rough hypermodules and then we obtain the relation between fuzzy rough sub-hypermodules and level rough sets. This relation is characterized as a necessary and sufficient condition. 相似文献