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41.
Cress seed mucilage (CSM) as a new source of biomacromolecule has gained attraction in food science due to its biodegradability and biocompatibility. In this research CSM–poly(vinyl alcohol) (PVA) nanofibers were produced under different conditions by electrospinning technique. Viscosity and electrical conductivity of the produced biopolymers were analyzed. The effect of CSM to PVA volume ratio and applied electrical field were evaluated on nanofiber morphology by scanning electron spectroscopy. The optimum nanofibers showed smooth and uniform surfaces with diameter size range of 95–278 nm. The results of Fourier transform infrared spectroscopy of CSM–PVA nanofiber with volume ratio of 60:40 showed characteristic peaks of CSM and PVA. X‐ray diffractometer data clearly revealed the amorphous structure of the electrospun nanofibers. Thermogravimetric and derivative thermogravimetric analysis indicated that thermal stability of electrospun nanofibers increased in comparison to CSM and PVA. The results of this study indicated that CSM can be applied as a new source of biopolymer for production of nanofibers that could be used for different applications such as delivery systems and packaging film fabrication. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45811. 相似文献
42.
In the gas industries, to increase the degree of accuracy of calculation and estimation in different processes, the importance of accurate prediction of gas properties is highlighted. The gas density, as one of the key properties in gas engineering, has a major effect in calculations. So, in the present paper, multi-layer perceptron artificial neural network (MLP-ANN) was used to predict the gas density based on molecular weight, critical pressure and critical temperature of gas, pressure, and temperature. To this end, a total number of 1240 reliable data of gas density were gathered from literature for the training and testing phases. The MLP-ANN outputs were compared with the actual data in different manners, such as statistical and graphical analyses. The coefficient of determination (R2), average absolute relative deviation (AARD), and root mean squared error (RMSE) for overall process were calculated as 1, 0.0088444, and 0.0259, respectively. The determined parameters and graphical analysis showed that the MLP-ANN has great potential and high degree of accuracy in gas density estimation. 相似文献
43.
Asphaltene precipitation and deposition in different parts of petroleum industry increase considerably cost and problems in oil production. Due to these facts controlling asphaltene precipitation becomes one of valuable topics for research in petroleum engineering. Utilization of Asphaltene inhibitors is known as one of the dominant methods for controlling asphaltene precipitation so in this paper Adaptive neuro-fuzzy inference system (ANFIS) is joint with Genetic Algorithm (GA) to study effectiveness of asphaltene inhibitors on precipitation in terms of oil and inhibitors properties. In order to prepare and evaluate the ANFIS-GA algorithm, some reliable experimental data were gathered. The obtained results from the comparison shows the coefficient of determination (R2) for training and testing phases are 0.98804 and 0.9916 respectively. The determined indexes and graphical comparisons expresses that ANFIS-GA has enough accuracy and potential to estimate effectiveness of inhibitors on asphaltene precipitation reductions. 相似文献
44.
Seyed Moein Elahi Milad Ahmadi Khoshooei Carlos E. Scott Zhangxin Chen Pedro Pereira‐Almao 《加拿大化工杂志》2019,97(Z1):1352-1360
45.
Razieh Salahandish Hossein Zargartalebi Mohsen Janmaleki Sultan Khetani Milad Azarmanesh Mehdi Mohammadi Ashani Raied Aburashed Maryam Vatani Ali Ghaffarinejad Amir Sanati‐Nezhad 《Advanced Materials Technologies》2019,4(11)
Electrochemical nanobiosensors are ultrasensitive tools used for detection and monitoring of various markers in biofluids. In the absence of reliable techniques for large‐scale production of reproducible nanomaterial structures on the electrodes, they are created individually in batch‐production. This has become a substantial hurdle in the practical implementation of electrochemical nanobiosensors. An automated microfluidic‐based platform (NanoChip) is presented for reproducible and scalable formation of complex nanomaterial constructs with a defined order of nanocomposites and biomaterials to create ultrasensitive nanobiosensors. The automated liquid handling system of the setup delivers reagents to electrodes inserted temporarily into the chip for modifying their surfaces by depositing different nanomaterials. The NanoChip platform is used for the creation of a multilayer nanocomposite structure on the electrode surface. These reproducible nanobiosensors are used for detecting breast cancer cells in the blood. The nanobiosensors offered a dynamic detection range of 10 to 5 × 106 cells mL−1. Performance of sensors produced from NanoChip shows similar selectivity and operational range along with improved sensitivity and reproducibility compared to sensors developed using batch process. These features make automated Nanochip technology a versatile tool for producing nanosensors for the ultrasensitive detection of various markers in biomedical, clinical, energy, and environmental applications. 相似文献
46.
This article presents a frequency selective surface (FSS) and rectenna array in parallel‐series connection to harvest power of wireless power systems. To improve the basic antenna parameters, a frequency selective surface was mounted on the reverse side of the substrate. According to the results, the proposed method showed significant improvement in comparison to other methods in both single and rectenna array. Moreover, the conversion efficiency of the presented technique was increased to 76%. The output voltage of 4.5 and 9 V and the current of 60 and 120 mA were resulted for 5 and 10 rectenna units, respectively. The proposed arrays can be expanded to large scale integrated array without any significant degradation in conversion efficiency. 相似文献
47.
Lucy Gloag Milad Mehdipour Dongfei Chen Richard D. Tilley J. Justin Gooding 《Advanced materials (Deerfield Beach, Fla.)》2019,31(48)
Magnetic nanoparticles (MNPs) are of high significance in sensing as they provide viable solutions to the enduring challenges related to lower detection limits and nonspecific effects. The rapid expansion in the applications of MNPs creates a need to overview the current state of the field of MNPs for sensing applications. In this review, the trends and concepts in the literature are critically appraised in terms of the opportunities and limitations of MNPs used for the most advanced sensing applications. The latest progress in MNP sensor technologies is overviewed with a focus on MNP structures and properties, as well as the strategies of incorporating these MNPs into devices. By looking at recent synthetic advancements, and the key challenges that face nanoparticle‐based sensors, this review aims to outline how to design, synthesize, and use MNPs to make the most effective and sensitive sensors. 相似文献
48.
49.
The effect of Zn dopant on the growth of cadmium oxide (CdO) nanostructures through a sonochemical method was investigated. The X-ray diffraction (XRD) patterns of the nanoparticles show CdO cubic structures for the produced samples. Field emission scanning electron microscope (FESEM) images reveal that morphologies of the samples change, when they are doped with Zn atoms, and their sizes reduce. Room temperature photoluminescence (PL) and UV-Vis spectrometers were used to study optical properties of the samples. Evaluation of optical properties indicates that different emission bands result from different transitions and the value of CdO energy band gap increases due to doping. Studies of electrical properties of the nanostructures demonstrate that Zn dopant enhances electrical conductivity and photocurrent generation as the result of light illumination on the nanostructures due to improved density of photo-generated carriers. Considering the obtained outcomes, Zn dopant can alter the physical property of the CdO nanostructures. 相似文献
50.
Roozbeh Siavash Moakhar Mehrad Mehdipour Mohammad Ghorbani Milad Mohebali Behrad Koohbor 《Journal of Materials Engineering and Performance》2013,22(9):2691-2697
In this study, failure of a high pressure economizer tube of a boiler used in gas-Mazut combined cycle power plants was studied. Failure analysis of the tube was accomplished by taking into account visual inspection, thickness measurement, and hardness testing as well as microstructural observations using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and x-ray diffraction (XRD). Optical microscopy images indicate that there is no phase transformation during service, and ferrite-pearlite remained. The results of XRD also revealed Iron sulfate (FeSO4) and Iron hydroxide sulfate (FeOH(SO4)) phases formed on the steel surface. A considerable amount of Sulfur was also detected on the outer surface of the tube by EDS analysis. Dew-point corrosion was found to be the principal reason for the failure of the examined tube while it has been left out-of-service. 相似文献