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991.
O. El Bounagui H. Erramli 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(9):1361-1366
In this work, we report on calculations of the electronic channelling energy loss of hydrogen and helium ions along Si〈1 0 0〉 and Si〈1 1 0〉 axial directions for the low energy range by using the Monte Carlo simulation code. Simulated and experimental data are compared for protons and He ions in the 〈1 0 0〉 and 〈1 1 0〉 axis of silicon. A reasonable agreement was found.Computer simulation was also employed to study the angular dependence of energy loss for 0.5, 0.8, 1, and 2 MeV channelled 4He ions transmitted through a silicon crystal of 3 μm thickness along the 〈1 0 0〉 axis. 相似文献
992.
H. Ben Naceur T. Mzoughi I. Moussa A. Rebey B. El Jani 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(3-4):236-240
InAs epilayers were grown by atmospheric pressure metal–organic vapor phase epitaxy on GaAs (1 0 0) exactly oriented substrates and misoriented by 2° and 10° toward [1 1 1]A. The layers had varying thicknesses and were deposited under the same growth conditions. Atomic force microscopy analysis show that surface morphology depends on surface misorientation and presents a low root mean square. High resolution X-ray diffraction analysis and Hall effect measurements were preformed to check the substrate misorientation effect on the crystalline quality and electrical properties respectively. 相似文献
993.
Rivera-Medina Carmen L.; Caraballo José Noel; Rodríguez-Cordero Elí R.; Bernal Guillermo; Dávila-Marrero Elixmahir 《Canadian Metallurgical Quarterly》2010,78(3):398
Objective: The authors of this study aimed to evaluate 2-factor structures for the Center for Epidemiologic Studies Depression Scale (CES-D) reported in the literature to determine which one proves to be a better fit with the data on low-income Puerto Ricans living on the island. Method: The sample consisted of 3,504 civilian noninstitutionalized Puerto Ricans, ranging in age from 18 to 64 who were living in low-income areas of Puerto Rico. A confirmatory factor analysis (CFA) was implemented, and model fit was assessed with the Tucker–Lewis Index (TLI), the comparative fit index (CFI), and the root-mean-square error of approximation (RMSEA). Results: The CFA results obtained for the Radloff (1977) and Guarnaccia, Angel, and Worobey (1989) models show that neither model obtained adequate fit indexes. Exploratory factor analysis revealed that the 2-factor structure not only obtained better fit indexes (TLI = .948, CFI = .955, RMSEA = .048) but also reflected a better conceptual organization of the factors (basically divided into 2 components: Negative Affect and Positive Affect). When we assessed the model fit by gender, the model consistently fit the data for the female subsample but not for the male one. Conclusions: Results confirm the need to address the issues related to measurement equivalence for specific cultural and language gaps in assessment of depressive symptoms. Lack of factor invariance across gender also raises the question of the appropriateness of this measure for the male subsample and the need for further research in the manifestation of depression in this group. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
995.
Yassine Kharbouch Abdelaziz Mimet Mohammed El Ganaoui Lahoucine Ouhsaine 《国际可持续能源杂志》2018,37(6):515-532
This study investigates the thermal energy potentials and economic feasibility of an air-conditioned family household-integrated phase change material (PCM) considering different climate zones in Morocco. A simulation-based optimisation was carried out in order to define the optimal design of a PCM-enhanced household envelope for thermal energy effectiveness and cost-effectiveness of predefined candidate solutions. The optimisation methodology is based on coupling Energyplus® as a dynamic simulation tool and GenOpt® as an optimisation tool. Considering the obtained optimum design strategies, a thermal energy and economic analysis are carried out to investigate PCMs’ integration feasibility in the Moroccan constructions. The results show that the PCM-integrated household envelope allows minimising the cooling/heating thermal energy demand vs. a reference household without PCM. While for the cost-effectiveness optimisation, it has been deduced that the economic feasibility is stilling insufficient under the actual PCM market conditions. The optimal design parameters results are also analysed. 相似文献
996.
M.P. Sanchez M. El Jabri S. Minéry V. Wolf E. Beuvier C. Laithier A. Delacroix-Buchet M. Brochard D. Boichard 《Journal of dairy science》2018,101(11):10048-10061
Cheese-making properties of pressed cooked cheeses (PCC) and soft cheeses (SC) were predicted from mid-infrared (MIR) spectra. The traits that were best predicted by MIR spectra (as determined by comparison with reference measurements) were 3 measures of laboratory cheese yield, 5 coagulation traits, and 1 acidification trait for PCC (initial pH; pH0PPC). Coefficients of determination of these traits ranged between 0.54 and 0.89. These 9 traits as well as milk composition traits (fatty acid, protein, mineral, lactose, and citrate content) were then predicted from 1,100,238 MIR spectra from 126,873 primiparous Montbéliarde cows. Using this data set, we estimated the corresponding genetic parameters of these traits by REML procedures. A univariate or bivariate repeatability animal model was used that included the fixed effects of herd × test day × spectrometer, stage of lactation, and year × month of calving as well as the random additive genetic, permanent environmental, and residual effects. Heritability estimates varied between 0.37 and 0.48 for the 9 cheese-making property traits analyzed. Coagulation traits were the ones with the highest heritability (0.42 to 0.48), whereas cheese yields and pH0 PPC had the lowest heritability (0.37 to 0.39). Strong favorable genetic correlations, with absolute values between 0.64 and 0.97, were found between different measures of cheese yield, between coagulation traits, between cheese yields and coagulation traits, and between coagulation traits measured for PCC and SC. In contrast, the genetic correlations between milk pH0 PPC and CY or coagulation traits were weak (?0.08 to 0.09). The genetic relationships between cheese-making property traits and milk composition were moderate to high. In particular, high levels of proteins, fatty acids, Ca, P, and Mg in milk were associated with better cheese yields and improved coagulation. Proteins in milk were strongly genetically correlated with coagulation traits and, to a lesser extent, with cheese yields, whereas fatty acids in milk were more genetically correlated with cheese yields than with coagulation traits. This study, carried out on a large scale in Montbéliarde cows, shows that MIR predictions of cheese yields and milk coagulation properties are sufficiently accurate to be used for genetic analyses. Cheese-making traits, as predicted from MIR spectra, are moderately heritable and could be integrated into breeding objectives without additional phenotyping cost, thus creating an opportunity for efficient improvement via selection. 相似文献
997.
998.
Effect of pretreatments and drying methods on physico‐chemical,sensory characteristics and nutritional value of oyster mushroom
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Ahmed R. M. Maray Mostafa K. Mostafa Alaa El‐Din M. A. El‐Fakhrany 《Journal of Food Processing and Preservation》2018,42(1)
This study was aimed to evaluate the effect of pretreatments and drying methods on the chemical, physico‐chemical, sensory characteristics and nutritional value of oyster mushroom. Chemical analysis of oyster mushroom (OM) showed that the values content were increased by many times when calculated on dry weight basis. Nine treatments of dried mushroom powders (DMP) were prepared using three drying methods (hot air drying, vacuum drying, and sun drying). Also, three pretreatments of each method of drying were used (untreated, blanching by steaming without or with steeped in 0.5% citric acid solution for 30 min).The results and statistical analysis revealed that, sun dried oyster mushroom samples (without pretreatments) were found to be the best. The DMP samples resulting of the sun drying had a highest physico‐chemical properties, sensory evaluation scores, and contents of the mineral elements and amino acids as compared to other pretreatments and drying methods.
Practical applications
Fresh mushrooms have high water content, high enzymatic activity and hence are highly perishable. Thus, in this study nine treatments of dried mushroom powders (DMP) were prepared using three drying methods (hot air drying, vacuum drying and sun drying).Also, three pretreatments of each method of drying were used (untreated, blanching by steaming without or with steeped in citric acid).The DMP samples (untreated) resulting of the sun drying were better than other pretreatments and drying methods regarding quality attributes. 相似文献999.
1000.
Lúðvík Elíasson 《Housing Studies》2017,32(1):35-59
The housing market boom in Iceland in 2004–2007 was driven by international and domestic developments. A simple demand and supply model is fitted to data through the recent boom–bust period. The price equation (demand) is improved by including net immigration as an explanatory variable showing that demographic factors, in addition to mortgage market restructuring, help in explaining swings in the housing market. Evidence of a house price bubble is no longer detected when accounting for the effects of immigration with 1 per cent net immigration yielding a 4–6 per cent rise in house prices. Accuracy in forecasting house price developments is improved by accounting for housing investment behaviour in a separate (supply) equation. The sharp fall in housing investment in 2009 cannot, however, be modelled without the introduction of a dummy variable, accounting for the sudden stop in financing as the Icelandic banking sector failed in late 2008. 相似文献