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31.
Nano sized polycrystalline soft ferrite particles with composition Cu1−xCoxFe2O4 (x =0.1, 0.3, 0.5, 0.7, 0.9) were synthesized by the sol–gel technique. The existence of well-defined single cubic spinel structure was confirmed in all the samples by X-ray diffraction. The crystallite size found by XRD varied from 14.8 to 34.0 nm. The microstructure was also characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Slight expansion of the unit cell was detected with the increase of Cobalt concentration, which may be attributed due to larger ionic radius of Co2+. Lattice parameter ranged from 8.34 Å to 8.37 Å for Co2+ from 0.1–0.9. The distribution of cations amongst A- and B-sites of the lattice was estimated by X-ray diffraction by using the R-factor technique. The results showed that both Cu2+ and Co2+ ions occupy mainly the B-site while Fe3+ ions were equally distributed among A- and B-sites. The data obtained from cation distribution analysis was used to determine the magnetic moment for each sample and VSM studies were also carried out to validate these calculations. Magnetic measurements showed that the saturation magnetization (Ms) and coercivity (Hc) increased with increasing cobalt content.  相似文献   
32.
The aim of this study was to investigate the effect of elastane linear density, thread density, and weave float on the stretch, recovery, and compression properties of bi-stretch woven fabrics for compression garments. Fabric samples were produced using elastane core-spun cotton yarns both in the warp and weft. The elastane linear density, fabric thread density, and weave float size were used as input variables while fabric contraction, subgarment pressure, fabric stretch, and recovery were taken as response variables. Two different elastane linear densities, i.e. 44 and 78 dtex, two different thread densities, and three different weave designs, i.e. 1/1 plain, 2/2 z-twill, and 3/3 z-twill were used. The results of fabric samples were analyzed in Minitab statistical software. The coefficients of determinations (R-sq values) of the regression equations showed good prediction ability of the developed statistical models. The findings of the study may be helpful in deciding appropriate manufacturing specifications of bi-stretch fabrics to attain specific stretch, recovery, and compression properties.  相似文献   
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Abstract

This study presents an integrated water quantity and quality management method for the entire Yellow River system where the eco-environment has been deteriorating and water quantity is very scarce. The supply and demand of water resources has been investigated. The integration of the concepts of water resources functional capacity and water resources functional deficit have been put forward, and their characteristics have been analyzed. The results, based on 1997 to 1999 data, indicate that approximately 39 percent of the total river length was of excellent to good quality, 26 percent was moderate, and 35 percent was poor to very poor. The total natural runoffs of the river were 31.8, 43.9, and 43.4 billion m3, and about 94, 65, and 71 percent of them were withdrawn for agricultural, industrial, and domestic uses in 1997, 1998, and 1999, respectively. The total water resources availabilities were 21.1, 28.8, and 29.2 billion m3 occupying about 66, 66, and 67 percent of the total runoffs in 1997, 1998, and 1999, respectively. From 1997 to 1999, the river could provide only 53 percent (on average) of the total water resources demand for the uses and discharge to the Bohai Sea; about 57 percent of the water deficiency resulted from pollution and 43 percent from quantity deficit. For the main pollution parameter (COD Mn ), the averages of water resources functional capacity and deficit were 29,571.54 and 199.70 kg, respectively; for NH 4-N, the averages of water resources functional capacity and deficit were 3774.26 and 113.08 kg, respectively. These demonstrated that the influence of NH 4-N on water resources availability was more than that of COD Mn and that the functional capacity was much higher than functional deficit, suggesting that the actual water quality was mostly better than the required one for water supply functions.  相似文献   
36.
Novel antihypercholesterolemic bioactive peptides (BAP) from peptic camel whey protein hydrolysates (CWPH) were generated at different time, temperature, and enzyme concentration (%). Hydrolysates showed higher pancreatic lipase- (PL; except 3 CWPH) and cholesterol esterase (CE)-inhibiting potential, as depicted by lower half-maximal inhibitory concentration values (IC50 values) compared with nonhydrolyzed camel whey proteins (CWP). Peptide sequencing and in silico data depicted that most BAP from CWPH could bind active site of PL, whereas as only 3 peptides could bind the active site of CE. Based on higher number of reactive residues in the BAP and greater number of substrate binding sites, FCCLGPVPP was identified as a potential CE-inhibitory peptide, and PAGNFLPPVAAAPVM, MLPLMLPFTMGY, and LRFPL were identified as PL inhibitors. Molecular docking of selected peptides showed hydrophilic and hydrophobic interactions between peptides and target enzymes. Thus, peptides derived from CWPH warrant further investigation as potential candidates for adjunct therapy for hypercholesterolemia.  相似文献   
37.
Fish processing industries result in an ample number of protein-rich byproducts, which have been used to produce protein hydrolysate (PH) for human consumption. Chemical, microbial, and enzymatic hydrolysis processes have been implemented for the production of fish PH (FPH) from diverse types of fish processing byproducts. FPH has been reported to possess bioactive active peptides known to exhibit various biological activities such as antioxidant, antimicrobial, angiotensin-I converting enzyme inhibition, calcium-binding ability, dipeptidyl peptidase-IV inhibition, immunomodulation, and antiproliferative activity, which are discussed comprehensively in this review. Appropriate conditions for the hydrolysis process (e.g., type and concentration of enzymes, time, and temperature) play an important role in achieving the desired level of hydrolysis, thus affecting the functional and bioactive properties and stability of FPH. This review provides an in-depth and comprehensive discussion on the sources, process parameters, purification as well as functional and bioactive properties of FPHs. The most recent research findings on the impact of production parameters, bitterness of peptide, storage, and food processing conditions on functional properties and stability of FPH were also reported. More importantly, the recent studies on biological activities of FPH and in vivo health benefits were discussed with the possible mechanism of action. Furthermore, FPH-polyphenol conjugate, encapsulation, and digestive stability of FPH were discussed in terms of their potential to be utilized as a nutraceutical ingredient. Last but not the least, various industrial applications of FPH and the fate of FPH in terms of limitations, hurdles, future research directions, and challenges have been addressed.  相似文献   
38.
The intention of this review article is to review the knowledge about interactions in organic binary liquid mixtures. Molecular interactions in organic binary liquid mixtures are interesting due to their extensive use in many fields of solution chemistry. The thermodynamics of component molecules present in various systems interacting are particularly interesting because they display fantastic results. Studies of different organic liquid mixtures represent the different modes of interactions prevailing in the component molecules. The number of parameters required describing the properties of a given class of mixtures increases sharply with the number of segment types involved. In recent years, the theoretical and experimental investigations of interactions between unlike molecules have been conveniently carried out using excess thermodynamic functions. The properties of liquid mixtures depend on the forces between molecules and on the nature and volume of these molecules, and change with the composition of the mixtures. This change, in turn, is reflected in the thermodynamic properties of the mixtures. The influence of significant contributions of a chemical, physical and geometrical nature that change excess thermodynamic properties is considered and explained in detail.  相似文献   
39.
In this work, composites were made by improved bonding of the cationized cellulosic fabric and some anionic matrix like Carboxymethyl Cellulose (CMC). Mercerized cotton fabric was cationized using cationization agent, TEXAMIN ECE with varying percentage from 1 to 10%. Those cationized cotton samples were incorporated in anionic matrices and the resultant composites were tested for mechanical properties on Universal Textile Tensile Testing machine. In the case of CMC as the matrix for the cationized reinforcement, the increasing trend in the tensile strength and elongation at break was observed. Scanning Electron Microscope images showed no extraordinary changes in the physical appearance of the cationized samples. Thermograms derived from Differential Scanning Calorimetry were informative for the evaluation of the thermal behavior of composites.  相似文献   
40.
Today, the production of energy from waste is not a new process; however, its implementation and application continue to be a challenge in developing countries. Despite the abundance of valuable waste in the urban markets of these countries, practices aiming at renewable energy generation are missing. In Thailand, so-called green markets are replete with renewable energy potential, but the practical implementation of this potential is rare. Therefore, the main purpose of this study is to show that the conversion of green waste into renewable energy is not only environmentally beneficial but also financially rewarding. This is demonstrated by exploring the energy potential of the market and conducting a benefit–cost analysis under two scenarios. The results illustrate that for the selected market, converting organic waste into biogas is advantageous both environmentally as well as financially; further, the benefit–cost ratio is three times higher after conversion, compared to before. Additionally, there is a huge margin of conversion and production of biogas. The policy makers and planners of Talaad Thai (Thailand's largest green market) should invest greater effort in initiating plans, and set an example for other markets in Thailand, in order to make this planet clean and green.  相似文献   
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