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Esmael Rostami Davood Heidaryan Hanif Fattahi Abbas Shockravi Mehdi Zarei Farokh Rakhshanderu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1924-1934
Four new dinaphthosulfide and dibenzosulfide aza podands were synthesized. The synthesis of these podands was performed under three different reaction conditions: 1) diester, K 2 CO 3 , methanol, and RT; 2) diester, ethanolamine, and microwave (MW); and 3) diacid dichloride, ethanolamine, Et 3 N, CH 2 Cl 2 , RT. Two kinds of diester (dinaphthosulfide and dibenzosulfide) were used for the preparation of dihydroxy podands. These dihydroxy podands were reacted with thionyl chloride to afford dichloro podands. The second route gave excellent yields of dihydroxy podands. Dichloro podands are more soluble than dihydroxy podands in conventional solvents such as methanol, chloroform, and acetonitrile. 相似文献
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Seyed Javad Ahmadi Ramin Yavari Parviz Ashtari Vanik Gholipour Leila Kamel Farokh Rakhshandehru 《中国化学》2012,30(1):177-182
In this work, the synthesis of the composite of cerium(IV) molybdophosphate (CMP) and polyacrylonitrile (PAN) was reported (CMP‐PAN). The material has been characterized by elemental and spectral (FT‐IR), X‐ray and thermal (TGA) analysis. Also the size analysis of the composite was done by scanning electron microscopy (SEM). Its chemical stability in acidic, basic and saline solutions and radiation stability up to 100 kGy total expose dose were assessed. Whereas the synthesized composite has ion exchange properties, its ion exchange capacity and behavior toward several metal ions were also investigated. Further, the distribution coefficients of the metal ions were calculated. Finally, the ability of the synthesized CMP‐PAN composite for the decontamination of low level liquid waste (LLLW) was investigated. 相似文献
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One of room acoustic goals, especially in small to medium rooms, is sound diffusion in low frequencies, which have been the
subject of lots of researches. Sound diffusion is a very important consideration in acoustics because it minimizes the coherent
reflections that cause problems. It also tends to make an enclosed space sound larger than it is. Diffusion is an excellent
alternative or complement to sound absorption in acoustic treatment because it doesn’t really remove much energy, which means
it can be used to effectively reduce reflections while still leaving an ambient or live sounding space. Distribution of diffusive
and nondiffusive surfaces on room walls affect sound diffusion in room, but the amount, combination, and location of these
surfaces are still the matter of question. This paper investigates effects of these issues on room acoustic frequency response
in different parts of the room with different source-receiver locations. Room acoustic model based on wave method is used
(implemented) which is very accurate and convenient for low frequencies in such rooms. Different distributions of acoustic
surfaces on room walls have been introduced to the model and room frequency response results are calculated. For the purpose
of comparison, some measurements results are presented. Finally for more smooth frequency response in small and medium rooms,
some suggestions are made. 相似文献
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Nirav Shah Subodha Kumar Farokh Bastani I-Ling Yen 《European Journal of Operational Research》2012,216(1):239-251
With limited economic and physical resources, it is not feasible to continually expand transportation infrastructure to adequately support the rapid growth in its usage. This is especially true for traffic coordination systems where the expansion of road infrastructure has not been able to keep pace with the increasing number of vehicles, thereby resulting in congestion and delays. Hence, in addition to striving for the construction of new roads, it is imperative to develop new intelligent transportation management and coordination systems. The effectiveness of a new technique can be evaluated by comparing it with the optimal capacity utilization. If this comparison indicates that substantial improvements are possible, then the cost of developing and deploying an intelligent traffic system can be justified. Moreover, developing an optimization model can also help in capacity planning. For instance, at a given level of demand, if the optimal solution worsens significantly, this implies that no amount of intelligent strategies can handle this demand, and expanding the infrastructure would be the only alternative. In this paper, we demonstrate these concepts through a case study of scheduling vehicles on a grid of intersecting roads. We develop two optimization models namely, the mixed integer programming model and the space-time network flow model, and show that the latter model is substantially more effective. Moreover, we prove that the problem is strongly NP-hard and develop two polynomial-time heuristics. The heuristic solutions are then compared with the optimal capacity utilization obtained using the space-time network model. We also present important managerial implications. 相似文献
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Tayyeb Ghadimi Soheila Naderi Gharahgheshlagh Noorahmad Latifi Ahmad Hivechi Vahid Hosseinpour Sarmadi Siamak Farokh Forghani Naser Amini Peiman B. Milan Fatemeh Latifi Masoud Hamidi Ghazaleh Larijani Seyed Mohammad Amin Haramshahi Motahareh Abdollahi Fatemeh Ghadimi Saeed Nezari 《Macromolecular bioscience》2023,23(9):2300033
Burn is one of the physically debilitating injuries that can be potentially fatal; therefore, providing appropriate coverage in order to reduce possible mortality risk and accelerate wound healing is mandatory. In this study, collagen/exo-polysaccharide (Col/EPS 1–3%) scaffolds are synthesized from rainbow trout (Oncorhynchus mykiss) skins incorporated with Rhodotorula mucilaginosa sp. GUMS16, respectively, for promoting Grade 3 burn wound healing. Physicochemical characterizations and, consequently, biological properties of the Col/EPS scaffolds are tested. The results show that the presence of EPS does not affect the minimum porosity dimensions, while raising the EPS amount significantly reduces the maximum porosity dimensions. Thermogravimetric analysis (TGA), FTIR, and tensile property results confirm the successful incorporation of the EPS into Col scaffolds. Furthermore,the biological results show that the increasing EPS does not affect Col biodegradability and cell viability, and the use of Col/EPS 1% on rat models displays a faster healing rate. Finally, histopathological examination reveals that the Col/EPS 1% treatment accelerates wound healing, through greater re-epithelialization and dermal remodeling, more abundant fibroblast cells and Col accumulation. These findings suggest that Col/EPS 1% promotes dermal wound healing via antioxidant and anti-inflammatory activities, which can be a potential medical process in the treatment of burn wounds. 相似文献
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