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排序方式: 共有480条查询结果,搜索用时 15 毫秒
51.
The target of this study is application of sub-critical water as a green solvent for hydrolysis of rice bran and extraction of its oil in order to obtain value-added materials. Experiments were carried out at temperatures ranging from 100 to 360 °C with 5 min residence time in a batch reactor. Four phases were isolated after reaction: hexane-soluble, acetone-soluble, water-soluble, and solid residue phases. Rice bran oil was successfully and efficiently obtained by sub-critical water extraction. Significant increases of total organic carbon (TOC) and total nitrogen (TN) in the water phase were also observed, because polysaccharides and proteins (generally bio-macro polymers) in rice bran were hydrolysed by sub-critical water. The highest yields of TOC and TN were 140 and 13 mg/g dry matter, respectively. As a result, varieties of compounds, such as amino acids, organic acids, and water-soluble saccharides, were identified in the water phase. In particular, significant amounts of water-soluble sugars (maximum yield of total sugars was nearly 190 mg/g dry matter) proved that sub-critical water was a promising medium for dissolution of biomass in water. Acetone-soluble contents were attributed to tar, carbonized biomass, and in general, water- and hexane-insoluble compounds. Solid residue consisted of mainly un-reacted rice bran and insoluble inorganic compounds. 相似文献
52.
Effect of copper nanoparticles on permeability, physical, and mechanical properties of particleboard
Effects of a 200 ppm nanocopper suspension, with size range from 10 to 80 nm, on the physical and mechanical properties of particleboard made on an industrial scale at the Iran-Choob Factory were studied. Nanocopper suspension was added to the mat at two levels of 100 and 150 ml/kg dry weight wood particles and compared with control boards. Results showed that hot-pressing time was reduced by 5.7 and 3.4 % when 100 and 150 ml of nanocopper were used, respectively. Also, both levels of nanocopper consumption had improving effects on physical and mechanical properties, although in some cases not significant. Permeability was significantly decreased to its lowest value in 150 ml/kg treatment. It can be concluded that 150 ml of nanocopper/kg may be used to improve the physical and mechanical properties, to reduce press time, and to decrease permeability in particleboards. For industrially accepted outcome, 150 ml/kg of nanocopper is recommended. 相似文献
53.
In this study, various Artificial Neural Networks (ANNs) were developed to estimate the production yield of greenhouse basil in Iran. For this purpose, the data collected by random method from 26 greenhouses in the region during four periods of plant cultivation in 2009–2010. The total input energy and energy ratio for basil production were 14,308,998 MJ ha?1 and 0.02, respectively. The developed ANN was a multilayer perceptron (MLP) with seven neurons in the input layer, one, two and three hidden layer(s) of various numbers of neurons and one neuron (basil yield) in the output layer. The input energies were human labor, diesel fuel, chemical fertilizers, farm yard manure, chemicals, electricity and transportation. Results showed, the ANN model having 7-20-20-1 topology can predict the yield value with higher accuracy. So, this two hidden layer topology was selected as the best model for estimating basil production of regional greenhouses with similar conditions. For the optimal model, the values of the models outputs correlated well with actual outputs, with coefficient of determination (R2) of 0.976. For this configuration, RMSE and MAE values were 0.046 and 0.035, respectively. Sensitivity analysis revealed that chemical fertilizers are the most significant parameter in the basil production. 相似文献
54.
Mahmoud Omid Mahmoud SoltaniMohammad Hadi Dehrouyeh Seyed Saeid MohtasebiHojat Ahmadi 《Journal of food engineering》2013
The main purpose of this research was design and development of an intelligent system based on combined fuzzy logic and machine vision techniques for grading of egg using parameters such as defects and size of eggs. The detected defects were internal blood spots, cracks and breakages of eggshell. The Hue-Saturation-Value (HSV) color space was found useful in obtaining visual features during Image Processing (IP) stage. The fuzzy inference system (FIS) was designed based on triangular and trapezoidal membership functions, fuzzy rules with logical operator of AND inference system of Mamdani and method of center average for defuzzifier. The evaluation results of IP algorithms showed that use of IP technique has good performance for defects and size detection. The Correct Classification rate (CCR) was 95% for size detection, 94.5% for crack detection and 98% for breakage detection. The overall accuracy FIS model in grading of the eggs was 95.4. 相似文献
55.
Hamed Safajou Mojgan Ghanbari Omid Amiri Hossein Khojasteh Farzad Namvar Sahar Zinatloo-Ajabshir Masoud Salavati-Niasari 《International Journal of Hydrogen Energy》2021,46(39):20534-20546
Recently, nanocomposite photocatalysts based on semiconductors have attracted much attention due to their suitable bandgap. Combination of tow of several semiconductors can slow down the electron-hole recombination. In this regard, we have depicted an eco-friendly and green fabrication technique to synthesize RGO/Cu nanocomposite by the reduction of graphene oxide and Cu2+ ion utilizing spearmint extract as a reductant and capping agent. The sample was identified by FTIR, XRD, FESEM, EDS, HRTEM, and CV. The results of photocatalytic performance revealed that RGO/Cu is an efficient catalyst for degrading organic pollutants. This compound can eliminate Rhodamine B (RhB) and Methylene blue (MB) 91.0% and 72.0%, respectively. 相似文献
56.
Fatemeh Sadat Razavi Morteza Hajizadeh-Oghaz Omid Amiri Maryam Sadat Morassaei Masoud Salavati-Niasari 《International Journal of Hydrogen Energy》2021,46(1):886-895
The study of the effect of different chelating agents in the Pechini method on the morphology has been a promising strategy that can be used for practical tuning of the nanoparticle's morphology and hence the electrochemical hydrogen storage capacity. In the current study, the conventional Pechini sol-gel approach was used to prepare the Ba2Co9O14 nanoparticles as a novel hydrogen storage material. The X-ray diffraction investigation approved the formation of Ba2Co9O14 with a Hexagonal crystal structure for all of the synthesized samples. The scanning electron microscopy (SEM) revealed when citric acid was used as a chelating agent, nanoparticles with finer and more uniform morphology were obtained rather than other chelating sources. The transmission electron microscopy (TEM) showed in the presence of citric acid; the size of the synthesized nanoparticles was between 14 and 24 nm. According to the Diffuse Reflectance Spectroscopy (DRS) analysis, the calculated bandgap of synthesized nanoparticles was approximately 3.2 eV, which indicates that synthesized nanoparticles were semiconductors in essence. The electrochemical hydrogen adsorption/desorption results showed that the sample synthesized by the citric acid has an enhancement in electrochemical hydrogen storage of approximately 800 mAh/g after 15 cycles. 相似文献
57.
Davoud Salarbashi Mohsen Tafaghodi Omid Rajabi Bibi Sedigheh Fazli Bazzaz Vahid Soheili 《Journal of Food Safety》2023,43(1):e13024
This study aimed to produce and characterize eco-friendly SSPS nanocomposites incorporated with various concentrations of TiO2 nanoparticles (NPs) (1%, 3%, and 7%). The antimicrobial activity of the nanocomposite films against five strains of pathogenic bacteria was examined. Salmonella typhi PTCC 1609 was the most sensitive species to TiO2 NPs at concentrations equal to the synthetic antibiotic. The migration of TiO2 to ethanol and acetic acid, as two food simulants increased when the initial nano-TiO2 content increased. The release profiles for TiO2 in two simulants of ethanol and acetic acid indicated a non-Fickian release, and the release kinetics were concentration-dependent. SSPS/TiO2 nanocomposites degraded easily and thus have the potential to be applied as an eco-friendly packaging system. Oral administration of doses of 1, 12.5, 25, 50, and 75 mg/kg TiO2 revealed that the dose of 50 and 75 mg/kg increased malondialdehyde (p < .001) concentration in the liver tissue. In addition, it decreased glutathione (p < .001) concentration in the liver tissue. 相似文献
58.
59.
Hajimahmoodi Mannan Khanavi Mahnaz Sadeghpour Omid Ardekani Mohammad Reza Shams Mazde Fatemeh Zamani Khoddami Mina Sadat Afzalifard Sheida Ranjbar Ali Mohammad 《Food Analytical Methods》2016,9(12):3451-3459
Food Analytical Methods - Vinegar as a nutraceutical substance is classified to various types related to the different substances applied in production process. Therefore, identity of the source... 相似文献
60.
Principles and Applications of Light Backscattering Imaging in Quality Evaluation of Agro-food Products: a Review 总被引:1,自引:0,他引:1
Kaveh Mollazade Mahmoud Omid Fardin Akhlaghian Tab Sayed Saeid Mohtasebi 《Food and Bioprocess Technology》2012,5(5):1465-1485
In recent years, due to the increasing consciousness of quality in the food and health sector, much progress has been made
in developing non-invasive techniques for the evaluation or inspection of internal qualitative parameters of fruits, vegetables,
and processed foodstuffs considering, e.g., moisture content, soluble solid content, acidity, and mechanical properties. This
paper reviews the theoretical and technical principles as well as the recent achievements and applications of light backscattering
imaging for nondestructive evaluation of food and agricultural produce. The results suggest the potential use of this emerging
technique in the food industry. Further attempts are pointed out to improve its performance through utilizing advanced image
processing coupled with artificial intelligence techniques. 相似文献