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排序方式: 共有1168条查询结果,搜索用时 140 毫秒
971.
Abolghasem Kazemi Vafa Faizi Arjomand Mehrabani-Zeinabad Mohamadjavad Hosseini 《分离科学与技术》2017,52(8):1387-1396
The process of separation of an ethanol–water mixture was simulated. A heat pump system was then implemented on the distillation column with the highest energy requirements in the process. Complete elimination of hot and cold utilities of the pretreatment column was obtained through an improved system by application of a heat pump at a compressor work of 406.6 kW. Installation of the heat pump system on the pretreatment column of the system results in a reduction of 10.7% of annual operating costs and 6.6% of the total annual costs (TAC). However, the capital costs of the process will enhance by 22.6%. 相似文献
972.
Minimum Spouting Velocity of Draft Tube Conical Spouted Beds Using the Neural Network Approach 下载免费PDF全文
Seyyed H. Hosseini Mohammadreza Valizadeh Martin Olazar Haritz Altzibar 《化学工程与技术》2017,40(6):1132-1139
A multilayer perceptron with back‐propagation learning algorithm is developed to predict the minimum spouting velocity (ums) in draft tube conical spouted beds. Six dimensionless variables involving ten essential geometric and operating parameters of the beds were taken as model inputs. To compare the model results with both experimental data and those predicted by the limited existing empirical equations, the root mean square error and the mean relative error are utilized. Although there is a complex relationship between the input variables and ums, and despite the huge number of data available, the steps of training and testing show good agreement with the corresponding experimental values. This demonstrates that an artificial neural network is a useful approach to predict ums, especially when the relationship between the geometric and operating parameters and ums is complex and difficult to define. 相似文献
973.
Mina Zare Erfan Rezvani Ghomi Prabhuraj D. Venkatraman Seeram Ramakrishna 《应用聚合物科学杂志》2021,138(38):50969
Silicone is a synthetic polymer widely used in the biomedical industry as implantable devices since 1940, owing to its excellent mechanical properties and biocompatibility. Silicone biomaterials are renowned for their biocompatibility due to their inert nature and hydrophobic surface. A timeline illustration shows critical development periods of using silicone in varied biomedical applications. In this review, silicone properties are discussed along with several biomedical applications, including medical inserts, speciality contact lenses, drains and shunts, urinary catheters, reconstructive gel fillers, craniofacial prosthesis, nerve conduits, and metatarsophalangeal joint implants. Silicones are prone to microbial infections when exposed and interactions with the host tissue. As in the case of medical inserts, the development of specific antimicrobial strategies is essential. The review highlights silicone implants' interaction with soft and bone tissue and various antimicrobial strategies, including surface coating, physical or chemical modifications, treating with antibiotics or plasma-activated surfaces to develop the resistance to bacterial infection. Finally, 3D printing technology, tissue engineering, regenerative medicine applications, and future trends are also critically presented, indicating the silicone's potential as a biomaterial. 相似文献
974.
Yuelei Zhang M. Barzegar Gerdroodbary Saleh Hosseini A.M. Abazari Zhixiong Li 《International Journal of Hydrogen Energy》2021,46(29):16048-16062
In this research study, a computational method is applied to examine the impacts of coaxial hybrid air and fuel jets on fuel mixing at the supersonic cross-flow of Mach = 4. This study examined the coaxial air and fuel jet effects on main parameters i. e. circulation, mixing efficiency, and fuel penetration. Computational Fluid Dynamic is employed for the modelling of the coaxial jet at cross supersonic flow. Reynolds Average Navier-Stocks equations with SST turbulence model for achieving hydrodynamic feature of the main model. Impacts of air-jet pressure and nozzle configurations on fuel distribution are also presented and the main effective factors for efficient fuel mixing condition are explained. Our results disclosed that injection of coaxial air and fuel jets at supersonic cross airflow significantly improves the fuel penetration and mixing inside the combustion chamber. Flow study analysis shows that the coaxial injector augments the spiral feature of the fuel jet, which surges fuel mixing downstream. Our circulation analysis confirms that circulation strength increases in far away from an injector by the injection of a coaxial air jet. 相似文献
975.
976.
Journal of Mechanical Science and Technology - This paper introduces a novel severe plastic deformation method entitled Friction assisted tubular channel pressing (FATCP) for producing... 相似文献
977.
978.
979.
Mehdi Barikani Erfan Oliaei Hadi Seddiqi Hengameh Honarkar 《Iranian Polymer Journal》2014,23(4):307-326
Chitin the second most abundant polysaccharide is synthesized by an enormous number of living organisms including fungi and insects. These biopolymers have found many applications in different areas such as: packaging material, membrane for removal of metal ions, dyes and pigments in waste water engineering; anti-cholesterol, fat binding, preservative and food additive in food industry; seed and fertilizer coating, controlled agrochemical release in agriculture; surface treatment, photographic paper in pulp and paper industry; moisturizer, body creams and lotions in cosmetics and toiletries. It has also found wide applications in biomedical such as tissue engineering, drug delivery, wound dressing, scaffolds, cancer diagnosis, etc. The majority of these versatile applications are coming of its non-toxicity, biocompatibility and biodegradability. Chitin is also easily processed as gel, membrane, and nanofiber. This review emphasizes an extensive bibliography of recent basic and applied research and investigations on the aspects of this interesting biopolymer including the recovery, preparation, modification and application of chitin and its derivatives and related compounds. A new class of biocompatible and biodegradable chitin-based polyurethane (PU) elastomer was also introduced and reviewed in this study and it was found that by incorporation of chitin into the PU elastomer backbone, biocompatibility and degradation rate of the final elastomer improved. PUs are one of the synthetic biocompatible polymers with excellent physical and mechanical properties. Combination of this polymer with chitin resulted to a new tailor-made biocompatible and biodegradable polymer with improved properties. These polymers have potential applications in various applications including biomedical. 相似文献
980.
The efficient delivery of daunorubicin loaded poly (lactic acid) (PLA)/multiwalled carbon nanotubes (MWCNT)/Fe3O4 composite nanofibers was investigated. The synthesized nanofibers were characterized using SEM, TEM, and XRD analysis. The proliferation inhibition effect of PLA/MWCNT/Fe3O4 nanofibrous scaffolds on leukemia K562 cell lines was investigated. The effect of nanofiber concentration on the daunorubicin delivery in the absence and presence of external magnetic field was also evaluated. The results indicated that the incorporation of daunorubicin into the prepared nanofibrous scaffold under applied magnetic field could have synergistic cytotoxic effect on leukemia cancer cells. The drug release mechanism followed the non-Fickian transport. 相似文献