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101.
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103.
Yaya Wang Wei Gao 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(8):987-993
Fuel quality, especially biodiesel, is highly dependent on its water content, and the major sources of water in the fuel relate to the transportation, production, and storage processes. In this present contribution, the multilayer perceptron artificial neural network (MLP-ANN) was applied to predict the water content of biodiesel and diesel blend in terms of temperature and composition. The proposed algorithm was trained and tested by utilizing 400 experimental data points which were extracted from the literature. Based on the results, the MLP-ANN model has great ability to estimate the water content of biodiesel and diesel blend. The R-squared (R2), root mean square error, average absolute relative deviation, and a?bsolute deviation parameters for the total data set are obtained, respectively, as 0.99784, 123919.1172, 3.3632, and 1.17%, which indicate the effective performance suggested by ANN. As the computational study is cheaper and easier than the experimental study, the developed software could be considered as an alternative for laboratory study, and the environmental effect of biodiesel and produced undesired product after biodiesel combustion which is directly related to the water content of biodiesel is estimable with the information released in this study. 相似文献
104.
Yan-fu He Hui Huang Xian-qing Yang Shu-xian Hao Yong-qiang Zhao 《International Journal of Food Properties》2018,21(1):1800-1810
The activation of the apoptosis pathway in tilapia muscle during postmortem storage was studied. Changes in caspase-3 activity, ATP content, cytochrome c levels, and ratio of Bcl-2/Bax levels of tilapia muscle were observed during postmortem storage at 20°C. Caspase-3 activity was found to be significantly increased at first, followed by a decrease (P < 0.05); the highest caspase-3 activity was observed at 1 h. The ATP content decreased significantly (P < 0.05), and almost exhausted after 10 h storage. The cytochrome c level in the cytosol showed a significant increase after 5 h of storage (P < 0.05), while the mitochondrial cytochrome c levels showed a decrease. The Bcl-2/Bax ratio was stable from 0–5 h, followed by a rapid decreased at 10–20 h and a significant increased after 20 h (P < 0.05), suggesting that the apoptosis process occurred until 20 h of postmortem storage. Thus, we concluded that the availability of ATP and the increase in cytosolic cytochrome c levels are essential for the activation of caspase-3, and that the former partly limits caspase-3 activity. 相似文献
105.
Nicolás Emanuel Tenaglia Roberto Enrique Boeri Juan Miguel Massone Alejandro Daniel Basso 《Materials Science & Technology》2018,34(16):1990-2000
The austemperability of seven high silicon cast steels with different alloy contents was characteri sed. The maximum round bar diameter that can be fully austempered changed from about 10?mm for an unalloyed steel to more than 70?mm for a low-alloy steel. The austemperability was calculated by applying a procedure based on a standard Jominy test and the characterisation of the microstructure along the Jominy sample. The method, which was validated experimentally, creates a relatively simple procedure to measure austemperability. Processing factors such as the ability of the salt bath to extract heat and the austempering temperature are accounted for the method. The metallographic study revealed the influence of microsegregation on hardenability, which is particularly important for cast steels. 相似文献
106.
Daniele de Almeida Paula Eduardo Basílio de Oliveira Alvaro Vianna Novaes de Carvalho Teixeira Ariana de Souza Soares Afonso Mota Ramos 《International Journal of Food Science & Technology》2018,53(2):475-483
This study addressed the correlation between physical characteristics of double emulsions and sensory perception, as the microstructure of these systems may provide the mechanism to understanding the initial cause of the altered salty taste. Thus, double emulsions (W/O/W) were prepared using different volumes of the internal aqueous phase while maintaining the same fat and sodium contents in the evaluated systems. Polyglycerol polyricinoleate (PGPR) and tween 80 were used as hydrophobic and hydrophilic emulsifiers, respectively. After preparation, the samples were stored at 25 °C for 4 days and submitted to analysis of optical microscopy, distribution and polydispersity of the oil droplets size, electrical conductivity, rheological behaviour and sensorial analysis. It was found that the use of different emulsifier concentrations (PGPR) did not influence the physical characteristics of the emulsions with the same formulation, but emulsions with different internal aqueous phase concentrations presented different results. These distinct characteristics may have influenced sensorial perception, as the emulsion with higher internal phase concentration was considered saltier. Thus, it can be concluded that structural differences of the double emulsions can be used to decrease the sodium contents without perceivable changes in salty taste. 相似文献
107.
《Strain》2018,54(4)
The present work focuses on an experimental analysis of different photoelastic extraction methods. An adapted test rig designed in order to evaluate several extraction methods, which come from the literature and 2 new proposed methods. Their comparisons point out dissimilar behaviours between them in an experimental environment. However, some specific cases require the use of most appropriate techniques to minimise the defects influence. Therefore, a specific application of the photoelasticity is presented to illustrate the meaning of the technique used. It mainly focuses on the determination of the residual stresses and their orientation inside photovoltaic crystal silicon wafers. 相似文献
108.
Shuang Yin Limei Pan Xia Fang Yufeng Li Yanpu Li Yongbao Feng Tai Qiu Jian Yang 《Ceramics International》2019,45(8):9994-10003
In this study, the low–toxicity monomer N, N–dimethylacrylamide (DMAA), serving as both gelling agent and pore–forming agent, was adopted to fabricate porous Si3N4 ceramics with a regulatable microstructure and property by aqueous gelcasting. Results indicate that monomer content played an important role in regulating and optimizing the properties of sintered bodies. With increasing monomer content (5.94–30.69?wt%), both slurry viscosity (maximum 0.14?Pa?s at 95.40 s?1) and green body strength (11.35–49.23?MPa) exhibited monotonic increasing trends, demonstrating superior mechanical properties to those obtained using the neurovirulent acrylamide (AM) gelling system. The increased monomer content not only improved porosity, but also promoted α→β–Si3N4 transformation as well as β–Si3N4 grain growth through enhancing the connectivity of interlocking pores and accelerating the vapor phase transport during liquid–phase sintering. These variations in phase composition and microstructure derived from the varied monomer content further resulted in monotonic changes in porosity (40.32–51.50%), mean pore size (0.27–0.38?μm), flexural strength (202.77–132.15?MPa), fracture toughness (2.93–2.32?MPa?m1/2), dielectric constant (3.48–2.78) and loss (3.52–3.09?×?10?3) at 10?GHz for sintered bodies, displaying an excellent comprehensive properties. This study suggests a promising prospect for DMAA in preparation of high–performance porous Si3N4 ceramics by aqueous gelcasting. 相似文献
109.
Critical loading conditions of amorphization,phase transformation,and dilation cracking in 6H‐silicon carbide 下载免费PDF全文
Zhonghuai Wu Weidong Liu Liangchi Zhang 《Journal of the American Ceramic Society》2018,101(8):3585-3596
Amorphization, phase transformation, and dilation cracking are 3 major deformation/failure mechanisms of monocrystalline 6H‐SiC. This paper studies their critical formation conditions and mechanisms under hydrostatic pressure and uniaxial compression and tension with the aid of large‐scale molecular dynamics simulations. It was found that under hydrostatic pressure the major deformation mechanism is amorphization, that under uniaxial compression the major mechanism turns to phase transformation at low temperature and amorphization at high temperature, and that under uniaxial tension the dominating mechanism becomes dilation cracking. Increasing the temperature reduces the thresholds significantly and brings about a heterogeneous deformation mode. The study further concluded that these deformation mechanisms and their thresholds can be predicted theoretically. 相似文献
110.
Musculoskeletal disorders (MSD) have a high impact on the health of dual role workers (student and work). The aim of this study was to analyse risk factor (active pauses and job position) associated with MSD in postgraduate students, Bogotá 2016. This Cross-sectional study was conducted in a random sample of 304 college graduate students and statistical analysis in SPSS version 24. We found that significant differences between non-performing active pauses and neck symptoms (P = 0.007), not stretching vs neck symptoms [OR = 2.4048 (1.0133–5.707)]; laptop use vs eyes [OR = 2.7132 (1.457–5.0526)], shoulders [OR = 10.6364 (4.9905–22.6697)], elbows (P = 0.04); non-mouse usage vs elbows (P = 0.028), hand-wrist (P = 0.043); non-forearm support vs lower back (P = 0.009). Results suggest association between non-performing active pauses, stretching and neck; use of laptop and eyes, shoulders and left elbow, non-mouse usage and on elbow and hand/right wrist, no forearm support on table and lower back. Symptom changes in the upper and lower limbs were identified. 相似文献