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51.
Silicon - Metformin (MF) and L. albuman are used to treat type 2 diabetes. Diabetes causes problems such as blindness and albumin excretion. In this study, metformin, L. albuman and a composition... 相似文献
52.
Silicon - Magnetic stirring is considered to be the most useful stirring method in semi-solid casting processes which doesn’t have the restrictions of the mechanical stirring. In this... 相似文献
53.
Silicon - SiO2 nano-particles are applied in different industries such as ceramic producing, glass making, cosmetic products, medicines, magnetic mixtures, heat and electric insulators and glazing... 相似文献
54.
A Modified Method for the Determination of N‐Nitrosodiethanolamine in Coconut Diethanolamide Using HPLC with Dual‐Wavelength UV–Vis Detector
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![点击此处可从《Journal of surfactants and detergents》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Ramin Mostafalu Abbas Banaei Mohammad Hadi Riazi Fatemeh Ghorbani 《Journal of surfactants and detergents》2016,19(2):431-435
A simple and novel method based on high‐performance liquid chromatography with dual‐wavelength ultraviolet detection at 234 and 254 nm has been developed for the determination of underivatized N‐nitrosodiethanolamine in coconut diethanolamide. The correlation coefficient obtained shows that the method is correct. 相似文献
55.
Fatemeh Asghari Roya Salehi Marziyeh Agazadeh Effat Alizadeh Khosro Adibkia Mohammad Samiei 《国际聚合物材料杂志》2016,65(14):720-728
The authors aimed to design nanofibrous (NF) scaffolds that facilitate odontogenic and osteogenic differentiation of human dental pulp-derived mesenchymal stem cells (DPSCs) in vitro. For this purpose, hydroxyapatite (HA)–loaded poly (L-lactic acid)/poly (?-caprolactone) (PLLA:PCL 2;1) blend NFs were prepared using the electrospinning method. Alizarin red activity and cell viability were evaluated by MTT assay, and SEM revealed the proliferation properties of NF scaffolds. QRT-PCR results demonstrated that HA-loaded PLLA/PCL can lead to osteoblast/odontoblast differentiation in DPSCs through the up-regulation of related genes, thus indicating that electrospun biodegradable PCL/PLA/HA has remarkable prospects as scaffolds for bone and tooth tissue engineering. 相似文献
56.
Seismic assessment of concrete buildings reinforced with shape memory alloy materials in different stories
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![点击此处可从《The Structural Design of Tall and Special Buildings》网站下载免费的PDF全文](/ch/ext_images/free.gif)
M. R. Shiravand M. A. Nashtaee S. Veismoradi 《The Structural Design of Tall and Special Buildings》2017,26(15)
Shape memory alloy (SMA) is a unique material with many beneficial characteristics such as superelasticity and excellent resistance against corrosion. However, the high expenses related to the material costs and difficulties associated with implementation of SMAs in reinforced concrete (RC) structures may limit their usage. To decrease the costs related to SMA installation, this paper investigates the seismic performance of RC moment‐resisting frames with the intention of specifying the optimal stories for SMA utilization. To this end, RC frames with 3, 5, 7, and 9 stories are modeled and various cases are considered for SMA locations in different story levels. For each building, 4 different cases are considered including a frame with regular steel reinforcement (Steel), a frame with SMAs in all story levels (full SMA), and 2 remaining cases consist of frames with SMAs in bottom and middle story levels only. In the first part, nonlinear dynamic time history analyses are conducted to evaluate the base shear, roof displacement, interstory, and residual drift demands of the structures using 10 ground‐motion records. In the second part, the incremental dynamic analysis is employed to assess the entire range of structural dynamic behavior. By using the generated data from incremental dynamic analysis procedure, fragility evaluation is conducted on multiple limit states to provide a comprehensive performance assessment for each case. The results indicate that frames with SMA in their lower story levels performed similar to frames equipped with SMA in all story levels. However, the fragility assessments show the better performance of frames with SMA in their bottom stories versus other cases. On this basis, the costs associated with SMA fabrication could be reduced noticeably (nearly two‐thirds) without sacrificing the overall performance of the frame and its post‐earthquake serviceability. 相似文献
57.
Vane liquid–gas demisters are widely used as one of the most efficient separators. To achieve higher liquid disposal and to avoid flooding, vanes are enhanced with drainage channels. In this research, the effects of drainage channel geometry parameters on the droplet removal efficiency have been investigated applying CFD techniques. The observed parameters are channel angle, channel height and channel length. The gas phase flow field was determined by the Eulerian method and the droplet flow field and trajectories were computed applying the Lagrangian method. The turbulent dispersion of the droplets was modeled using the discrete random walk (DRW) approach. The CFD simulation results indicate that by applying DRW model, the droplet separation efficiency predictions for small droplets are closer to the corresponding experimental data. The CFD simulation results showed that in the vane, enhanced with drainage channels, fewer low velocity sectors were observed in the gas flow field due to more turbulence. Consequently, the droplets had a higher chance of hitting the vane walls leading to higher separation efficiency. On the other hand, the parameters affect the liquid droplet trajectory leading to the changes in separation efficiency and hydrodynamic characteristic of the vane. To attain the overall optimum geometry of the drainage channel, all three geometry parameters were simultaneously studied employing 27 CFD simulation cases. To interpolate the overall optimal geometry a surface methodology method was used to fit the achieved CFD simulation data and finally a polynomial equation was proposed. 相似文献
58.
Mahdieh Namvar-Mahboub Ahsani Fatemeh Ansari Soudabeh 《Theoretical Foundations of Chemical Engineering》2020,54(5):940-948
Theoretical Foundations of Chemical Engineering - Effect of activating procedure on the physic-chemical properties and adsorption performance of activated carbon was investigated. For this,... 相似文献
59.
Naser?AkhlaghiEmail author Riyaz?Kharrat Fatemeh?Rezaei 《Theoretical Foundations of Chemical Engineering》2017,51(1):65-69
Gas assisted gravity drainage (GAGD) is a novel subdivision of gas injection method. In this method the injection wells are located in the upper bed of the oil zone, and the production wells are drilled at the bottom bed of the oil zone. Reservoir simulation is among the decision tools for investigating production rate and selecting the best scenarios for developing the oil and gas fields. Selecting the location of the injection wells for reaching the optimized pressure and production rate is one of the most significant challenges during the injection process. Recent experiences have shown that artificial intelligence (AI) is a reliable solution for taking the mentioned decision appropriately and in a least possible time. This study is attributed to the investigation of applying the artificial neural network (ANN) as an artificial intelligence method and a potent predictor for choosing the most proper location for injection in a GAGD process in a fractured carbonate reservoir. The results of this investigation clearly show the efficiency of the ANN as a powerful tool for optimizing the location of the injection wells in a GAGD process. The comparison between the results of ANN and black oil simulator indicated that the predictions obtained from the ANN is highly reliable. In fact the production flow rate and pressure can be obtained in every possible location of the injection well. 相似文献
60.
Simin Hedayatnia Hamed Mirhosseini Sahar Tamnak Fatemeh Golpira 《Food and Bioprocess Technology》2016,9(4):686-698
This study was conducted to investigate the effects of inulin (0, 2.5, 5, and 7.5 %), maltodextrin (0, 15, 20, and 25 %), and different drying processes (one- and two-stage drying) on the morphology and physicochemical properties of regular and instant reduced-fat creamers. The present study showed that the drum-dried creamer containing 0 % maltodextrin and 0 % inulin was fully sticky powder with dark brown color. It was found that the maximum increase in maltodextrin (from 0 to 25 %) and inulin (from 0 to 7.5 %) resulted in the creamer with the highest glass transition temperature and the lowest stickiness among all formulated creamers. The application of two-stage drying involving fluidized bed drying resulted in further improvement of the glass transition temperature and stickiness of the reduced fat instant creamer. The instant creamers obtained from two-stage drying had considerably higher glass transition temperature and lower bulk density than the regular creamers from one-stage drying. Such improvement could be due to the reduction of bulk density induced by fluidized bed drying. This might be because of higher porosity of the creamer particles after agglomeration. The current study revealed that the addition of high amounts of inulin and maltodextrin also played a significant role in the reduction of bulk density and further improvement of glass transition temperature (Tg) and solubility of the reduced fat creamer. The instant reduced fat creamer containing 25 % maltodextrin and 7.5 % inulin had the most desirable characteristics among all formulated creamers. 相似文献