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101.
The 1996 Welfare to Work Mandate has had a significant impact on the lives of families that use public assistance. What role can university counseling and psychology training programs play in the facilitation of this mandate that is intended to return welfare recipients to work? The Welfare Reform Act is discussed in relation to an innovative program that provides graduate-level training for bachelor's-level social service workers to meet the challenges of new service-delivery mandates. Relevance of this collaborative effort to professional psychology is explored, and implications for training master's-level graduate students are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Masoud Salavati-Niasari Faezeh Soofivand Ali Sobhani-Nasab Maryam Shakouri-Arani Masood Hamadanian Samira Bagheri 《Journal of Materials Science: Materials in Electronics》2017,28(20):14965-14973
In this work, CdTiO3 nanoparticles were synthesized through reaction between Cd(CH3COO)2.2H2O, Ti(OC4H9)4, trimesic acid as a new chelating agent and ethanol as solvent by Pechini sol–gel method. X-ray diffraction (XRD) patterns showed that CdTiO3 nanostructures have rhombohedral structure with diameter of about 35.61 nm. The structure, morphology and size of CdTiO3 nanoparticles were characterized by FT-IR, XRD, SEM and EDAX. The optical properties of the products were studied by DRS. Based on the results of experiments, it was found that temperature and time of calcination, pH and the solvent of reaction are important parameters for formation of CdTiO3 nanoparticles. Utilizing trimesic acid (benzene-1,3,5-tricarboxylic acid) as a new chelating agent for preparation of CdTiO3 nanostructures was initiative of this work. 相似文献
103.
104.
Abdelaziz Zouari Abdessalem Trabelsi Adel Ben Arab 《Solar Energy Materials & Solar Cells》2008,92(3):313-322
A simple analytical model has been developed to simulate the performance of solar cells with polysilicon contact on the front surface. The polysilicon layer with a columnar grain structure is modeled by an effective recombination velocity using a two-dimensional transport equation. A one-dimensional transport equation in the single-crystal emitter is solved, taking into account bulk recombination and non-uniformly doped emitter. Then, simple analytical expressions for the emitter reverse saturation current and light-generated current densities are obtained. The collection of the light-generated carriers in polysilicon layer has been discussed and an analytical solution of the light-generated current is derived. The results show that the polysilicon layer can result in a decrease in emitter reverse saturation current density and an increase in solar cell photovoltaic parameters. In fact, the emitter region should not be treated as a ‘dead layer’ because thin polysilicon layer front surface contact gives an improvement of about 60 mV for the open-circuit voltage, 3.6 mA/cm2 for the photocurrent, and 3.9% for the cell efficiency. 相似文献
105.
Partition coefficients of six migrants between four simulated foods (water, 10% ethanol, 3% acetic acid, 95% ethanol) and air were determined by the phase ratio variation (PRV) method using headspace analyses by gas chromatography. The migrants were ethyl acetate, methyl ethyl ketone, propyl alcohol, butyraldehyde, acetaldehyde and acetonitrile. The results showed that migrant absorption by the four food simulants was highly dependent on the physicochemical properties of migrants and foods, such as polarity, solubility and hydrogen-bonding. 相似文献
106.
The oxidation of alcohols with tert-butylhydroperoxide (TBHP), in the presence of Mn2+ complexes immobilized in the pore channels of mesoporous hexagonal molecular sieves (HMS), were investigated. It was found that immobilized [Mn(bpy)2]2+/HMS is an efficient catalyst for the oxidation of alcohols such as benzyl alcohol, n-hexanol and cyclohexanol. The effects of reaction time, amount of Mn2+ in the catalyst, type of substrates and oxidants in this catalysis system were investigated. At optimum conditions, TBHP is more efficient oxidant with respect to H2O2. Following order has been observed for the percentage of conversions of alcohols: benzylic >1° >2°. 相似文献
107.
This study investigates the effect of clay addition on the broadband dielectric properties of multi‐walled carbon nanotube/polyvinylidene fluoride (MWCNT/PVDF) composites, that is, frequency range of 101−106 Hz. Different loadings of MWCNT and clay were used for the preparation of three‐phase (MWCNT/Clay/PVDF) nanocomposites via melt‐mixing method. The crystalline structure and morphology of nanocomposites were examined by employing characterization techniques such as X‐ray diffraction, transmission electron microscopy, and differential scanning calorimetry. The dielectric spectroscopy showed that introducing clay into the MWCNT/PVDF nanocomposites at a critical MWCNT concentration improved dielectric properties tremendously. It was interestingly observed that the incorporation of a specific amount of clay, that is, 1.0 wt%, into the (MWCNT/PVDF) nanocomposite at a critical MWCNT loading, that is, 0.5 wt% MWCNT, resulted in a huge increase in the dielectric permittivity (670% at 100 Hz) and a considerable reduction in the dissipation factor (68% at 100 Hz). POLYM. COMPOS., 161–167, 2016. © 2014 Society of Plastics Engineers 相似文献
108.
Empirical evaluation of river basin sustainability affected by inter‐basin water transfer using composite indicators
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Maryam Kefayati Bahram Saghafian Azadeh Ahmadi Hossein Babazadeh 《Water and Environment Journal》2018,32(1):104-111
In this study, a practical approach to evaluate the sustainability of river basins subjected to an inter‐basin water transfer project is developed. Selection of appropriate evaluation indicators is pivotal to such approach. To make use of huge amount of data, composite indicators of sustainability (CIS) should be utilised. The proposed approach relies on 15 sustainability indicators (SI) that cover three major criteria namely (economic, social and environmental), and aggregates them into eight different types of sustainability indices for a more robust outcome. Two scenarios were considered within the source and recipient basins. Furthermore, multivariate principal component analysis (PCA) was applied to determine principal and non‐principal indicators for the two river basins. The ability of CIS and PCA methods were verified via correlation and simple regression methods respectively. The results demonstrated that inter‐basin water transfer may improve sustainability, provided that a proper water resource management is enforced. 相似文献
109.
Schiff base complex of copper-functionalized MCM-41 (Cu-complex@MCM-41) was synthesized and used as an efficient and novel heterogeneous catalyst for the oxidative coupling of thiols into corresponding disulfides and oxidation of sulfides to sulfoxides using hydrogen peroxide (H2O2) as the oxidant. An aliphatic and aromatic series of sulfides and thiols including various functional groups were successfully converted into corresponding products. The all products were obtained in good to excellent yields. The mesoporous catalyst is characterized by FT-IR spectroscopy, BET, XRD, SEM, EDS and TGA. Recovery of the catalyst is easily achieved by simple filtration and reused for several consecutive runs without significant loss of its catalytic efficiency. 相似文献
110.
Saharnaz Ahmadi Maryam Farokhi Parisa Padidar Mojtaba Falahati 《International journal of molecular sciences》2015,16(8):17289-17302
In this study the effect of surface modification of mesoporous silica nanoparticles (MSNs) on its adsorption capacities and protein stability after immobilization of beta-lactoglobulin B (BLG-B) was investigated. For this purpose, non-functionalized (KIT-6) and aminopropyl-functionalized cubic Ia3d mesoporous silica ([n-PrNH2-KIT-6]) nanoparticles were used as nanoporous supports. Aminopropyl-functionalized mesoporous nanoparticles exhibited more potential candidates for BLG-B adsorption and minimum BLG leaching than non-functionalized nanoparticles. It was observed that the amount of adsorbed BLG is dependent on the initial BLG concentration for both KIT-6 and [n-PrNH2-KIT-6] mesoporous nanoparticles. Also larger amounts of BLG-B on KIT-6 was immobilized upon raising the temperature of the medium from 4 to 55 °C while such increase was undetectable in the case of immobilization of BLG-B on the [n-PrNH2-KIT-6]. At temperatures above 55 °C the amounts of adsorbed BLG on both studied nanomaterials decreased significantly. By Differential scanning calorimetry or DSC analysis the heterogeneity of the protein solution and increase in Tm may indicate that immobilization of BLG-B onto the modified KIT-6 results in higher thermal stability compared to unmodified one. The obtained results provide several crucial factors in determining the mechanism(s) of protein adsorption and stability on the nanostructured solid supports and the development of engineered nano-biomaterials for controlled drug-delivery systems and biomimetic interfaces for the immobilization of living cells. 相似文献