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101.
N. A. Ibrahim A. Hashem M. H. Abou-Shosha 《Polymer-Plastics Technology and Engineering》2013,52(6):963-971
Inexpensive and efficient cellulose-based adsorbents were prepared by the reaction of cross-linked polyethylenimine (CPEI) with an agricultural waste (i.e., wood sawdust). Factors affecting the extent of amination, such a CPEI concentration, pH, time, and temperature of reaction as well as sawdust particle size range, were studied. The obtained adsorbents were found to be highly effective for removal of anionic dyestuffs (i.e., direct, reactive, and acid dyes) from aqueous solutions. The presence of CPEI on and/or within the purified sawdust provides cationic active sites (i.e., amino groups) and enhances the substantivity of wood cellulose for anionic dyes, thereby improving the percent color removal. 相似文献
102.
103.
Improving energy use efficiency of canola production using data envelopment analysis (DEA) approach 总被引:1,自引:0,他引:1
In this study energy use pattern for canola production in Golestan province of Iran was studied and the degrees of technical and scale efficiency of producers were analyzed using a non-parametric data envelopment analysis technique. The study also helped to identify the wasteful uses of energy by inefficient farmers and to suggest reasonable savings in energy uses from different inputs. Further, the effect of optimization of energy on energy ratio and energy productivity was investigated. Data used in this study were obtained from 130 randomly selected canola farms from Golestan, the most important center of canola production in Iran. The inputs were human labor, diesel, machinery, fertilizers, chemicals, water for irrigation, seeds and electrical energies; while the yield value of canola was considered as output. The results revealed that, the total energy of 17,786 MJ ha−1 was consumed for canola production; about 15% of farmers were found to be technically efficient and the mean efficiency of farmers was found to be 0.74 and 0.88 under constant and variable returns to scale assumptions, respectively. The results also suggested that, on average, a potential 9.5% (1696 MJ ha−1) reduction in total energy input could be achieved provided that all farmers operated efficiently. 相似文献
104.
Hashem Sharghi Reza Khalifeh Seyed Gholamhossein Mansouri Mahdi Aberi Mohammad Mehdi Eskandari 《Catalysis Letters》2011,141(12):1845-1850
Abstract
A series of 2-(hetero)arylbenzimidazoles were synthesized by the catalytic condensation of (hetero)aryl aldehydes with 1,2-phenylenediamine derivatives at room temperature in the presence of air as the oxidant. Copper nanoparticles on charcoal was employed as an efficient and mild catalyst for this methodology. 相似文献105.
106.
107.
In this paper, we have presented an analytic solution for two 2-level identical atoms interacting with a single-mode quantized
radiation field, taking into account the level shifts produced by Stark shift. We assume that the two atoms are initially
prepared in the exited state and the field in a coherent state. We investigate the purity loss of the system and bipartite
partitions of the system. The effects of the Stark shift on the purity loss of the system and different bipartite partitions
of the system (field-two atoms, atom-(field+atom)) through the tangles are considered. In particular, the effect of the Stark
shift on the amount of entanglement between atoms and field is evaluated by the negativity. 相似文献
108.
Journal of Computer Virology and Hacking Techniques - In recent years, malware authors have had significant developments in offering new generations of malware and have tried to use different... 相似文献
109.
In this study a non-parametric method of data envelopment analysis (DEA) was applied to analyze the efficiency of farmers, discriminate efficient farmers from inefficient ones and to identify wasteful uses of energy in order to optimize the energy inputs for apple production in Tehran province, Iran. From this study the following results were obtained: from the total of 56 farmers, considered for the analysis, 34% and 54% were found to be technically and pure technically efficient, respectively. The technical, pure technical and scale efficiency scores of farmers were 0.7857, 0.8982 and 0.8666, respectively. Optimum energy requirement was found to be 37993.15 MJ ha−1; indicating that 11.29% of total energy input could be saved if the recommendations of this study are followed. From total energy saving, the contribution of electrical energy was the highest; it followed by chemicals energy inputs; implying that there was a great scope for saving energy inputs by improving the use pattern of these inputs. The results of economical analysis showed that the total costs of production could decreased from 8227.70 to 7570.01 $ ha−1; also the benefit to cost ratio and productivity improved from 1.24 to 1.34 and 2.52 to 2.74, respectively. 相似文献
110.
Seyed Mohammad Hashem Hosseini Zahra Emam-Djomeh Seyed Hadi Razavi Ali Akbar Moosavi-Movahedi Ali Akbar Saboury Mohammad Amin Mohammadifar Asgar Farahnaky Maliheh Sadat Atri Paul Van der Meeren 《Food chemistry》2013
The influence of κ-carrageenan (KC) depolymerization using ultrasound on its interaction with β-lactoglobulin (BLG) was investigated by isothermal titration calorimetry (ITC), turbidity measurement, dynamic light scattering and zeta-potential analyses. Time and amplitude of the sonication had a direct effect on the viscosity depression, while the sonication temperature had an opposite effect. ITC measurements indicated that the sonication significantly decreased the affinity constant between KC and BLG. The zeta-potential of the nanoparticles produced from ultrasonicated (US) KC–BLG associative interaction was lower than of those produced from intact (IN) KC–BLG interaction. These differences were attributed to the lower charge density of the KC (US) as a result of sonochemical interactions. Polydispersity and particle size measurements showed that the effect of the sonication was the homogenisation of the nanoparticles in the mixed dispersion. The nanoparticles formed may therefore be useful as a delivery system for fortification purposes of acidic beverages. 相似文献