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131.

The objective of the study is to identify the factors that lead to the adoption of rainwater harvesting in enabling sustainable ground water. The Theory of Planned Behavior and Norm Activation Model has been adopted. The sample consists of 400 participants who were either constructing and likely to construct houses have been considered for the study. Structural Equation Modelling was used to analyze the data. The study results exhibited the adoption of rainwater harvesting, and the moderation effect of intention to acquire rainwater harvesting knowledge on the relationship between environmental concern; environmental responsibility and rainwater harvesting. Based on the results, significant theoretical and practical implications have been made.

  相似文献   
132.
The inhibition of rice bran lipase (RBL) by diethyl-p-nitrophenyl phosphate was studied with reference to kinetics, nature of inhibition and also elucidate the effect of the inhibitor on the structure—function of the enzyme. Enzyme activity measurements shows that the inhibitor is more effective at 0.050 mM concentration of diethyl-p-nitrophenyl phosphate and the activity is 50% at this level of inhibitor concentration. The affinity of substrate for the enzyme was observed by the increase in the velocity of the reaction with increase in the substrate concentrations and double reciprocal plot indicates that the inhibition followed a competitive in nature and inhibition constant K i is found to be 0.016 mM at pH 7.0. The decrease in apparent thermal denaturation temperature to 4 °C compared to control indicates the destabilization of enzyme in the presence of inhibitor. Fluorescence spectral measurements suggests that pronounced quenching of fluorescence intensity of RBL occurs at higher concentrations of diethyl-p-nitrophenyl phosphate and ‘K a’ value was found to be 2.4 × 104 M−1 with free energy change ΔGo—26 kJ/mol at 30 °C suggesting strong binding between the enzyme and the inhibitor with microenvironmental changes occur at the active site or in the neighbourhood of active site. The far UV-CD data suggest that there is no significant changes in the conformation of the enzyme as a result of binding of diethyl-p-nitrophenyl phosphate. These results indicate that diethyl-p-nitrophenyl phosphate is a inhibitor of RBL and binds to the enzyme in brining about inhibition without any structural alterations.  相似文献   
133.
The dried spongy fruit of luffa (Luffa cylindrica L.), a cucurbitaceous crop available in abundance in tropical and sub-tropical countries has been found to be a promising material for immobilizing microbial cells. The aim of the present study was to examine the ethanol production from mahula flowers in submerged fermentation using whole cells of Saccharomyces cerevisiae immobilized in luffa sponge discs. The cells not only survived but also were physiologically active in three more cycles of fermentation without significant reduction (<5%) in ethanol production. After 96 h, there was 91.1% sugar conversion producing 223.2 g ethanol/kg flowers (1st cycle) which was 0.99%, 2.3% and 3.2% more than 2nd (221 g ethanol/kg flowers), 3rd (218 g ethanol/kg flowers) and 4th (216 g ethanol/kg flowers) cycle of fermentation, respectively. Furthermore, ethanol production by immobilized cells was 8.96% higher than the free cells.  相似文献   
134.
Performance of mixed flow compressor with un-shrouded impeller strongly depends upon unsteady, asymmetrical flow fields in the axial directions. The flow through the mixed flow impeller is complex due to three-dimensional nature of geometry. In mixed flow impeller, there are clearances between the rotating impeller blades and the casing as the high pressure ratio compressors are usually open shrouded impellers. As a result, certain amount of reduction in the performance is unavoidable due to clearance flows. In the present investigations, numerical analysis is performed using a commercial code to investigate tip clearance effects on through flow. The perform- ance of mixed flow impeller with four different clearances between impeller and stationary shroud are evaluated and compared with experimental results. The impeller performance map was obtained for different operating speeds and mass flow rates with different tip clearances. The result shows that the tip leakage flow strongly inter- acts with mainstream and contributes to total pressure loss and performance reduction. The pressure and per- formance decrement are approximately linearly proportional to the gap between impeller and stationary shroud. The analysis showed scope for improvement in design of the compressor for better performance in terms of effi- ciency and operating range.  相似文献   
135.
In this experimental study, hydrogen was inducted along with air and diesel was injected into the cylinder using a high pressure common rail system, in a single cylinder homogeneous charge compression ignition engine. An electronic controller was used to set the required injection timing of diesel for best thermal efficiency. The influences of hydrogen to diesel energy ratio, output of the engine and exhaust gas recirculation (EGR) on performance, emissions and combustion were studied in detail. An increase in the amount of hydrogen improved the thermal efficiency by retarding the combustion process. It also lowered the exhaust emissions. Large amounts of hydrogen and EGR were needed at high outputs for suppressing knock. The range of operation was brake mean effective pressures of 2–4 bar. The levels of HC and CO emitted were not significantly influenced by the amount of hydrogen that was used.  相似文献   
136.
The results are presented of exposure to a controlled high-temperature erosive gas stream of a series of alloys, which were selected to represent the range of microstructures and mechanical properties available in commercial high-temperature alloys. Analysis of the kinetic and morphological data suggested that the high-temperature oxidation behavior of a given alloy plays a very important role in determining its erosion-corrosion behavior under the conditions studied. In terms of relative behavior, alloys which are weak but ductile at temperature, and which form tenacious oxide scales, exhibited the highest resistance to high-temperature erosion-corrosion. Simple models were developed to describe the expected interaction between high-temperature oxidation and erosion.  相似文献   
137.
Two screening methods aimed at selection of predictor variables for use in a statistical downscaling (SD) model developed for precipitation are proposed and evaluated in this study. The SD model developed in this study relies heavily on appropriate predictors chosen and accurate relationships between site-specific predictand (i.e. precipitation) and general circulation model (GCM)-scale predictors for providing future projections at different spatial and temporal scales. Methods to characterize these relationships via rigid and flexible functional forms of relationships using mixed integer nonlinear programming (MINLP) formulation with binary variables, and artificial neural network (ANN) methods respectively are developed and evaluated in this study. The proposed methods and three additional methods based on the correlations between predictors and predictand, stepwise regression (SWR) and principal component analysis (PCA) are evaluated in this study. The screening methods are evaluated by employing them in conjunction with an SD model at 22 rain gauge locations in south Florida, USA. The predictor variables that are selected by different predictor selection methods are used in a statistical downscaling model developed in this study to downscale precipitation at a monthly temporal scale. Results suggest that optimal selection of variables using MINLP and ANN provided improved performance and error measures compared to two other models that did not use these methods for screening the variables. Results from application and evaluations of screening methods indicate improved downscaling of precipitation is possible by SD models when an optimal set of predictors are used and the selection of the predictors is site-specific.  相似文献   
138.
Abstract: Recent evidence has demonstrated that nitrites play an important role in the cardiovascular system. Fennel (Foneiculum vulgare) seeds are often used as mouth fresheners after a meal in both the Indian sub‐continent and around the world. The present study aims to quantify the nitrite and nitrates in fennel seeds as well as elucidating the effect of fennel derived‐nitrites on vascular functions. Results from our study show that fennel seeds contain significantly higher amount of nitrites when compared to other commonly used post‐meal seeds. Furthermore our study confirmed the functional effects of fennel derived‐nitrites using in vitro and ex vivo models that describe the promotion of angiogenesis, cell migration, and vasorelaxation. We also showed that chewing fennel seeds enhanced nitrite content of saliva. Thus our study indicates the potential role of fennel derived‐nitrites on the vascular system. Practical Application: This study is focused on determining the effect of fennel‐derived nitrites on angiogenesis (the formation of new blood vessels from pre‐existing ones), cell migration, and vasorelaxation (dilation of blood vessels) thereby preserving cardiovascular health.  相似文献   
139.
Data on pubertal maturation in male marmoset, a model for human reproduction, are scant and conflicting. We collected data on novel parameters to characterize puberty. Twenty-five marmoset monkeys were assigned to five age groups by weeks (wk): 21 (pre-pubertal), 43 (onset of puberty), 52 (fully pubertal), 70 (mature), and 116 (fully adult). Serum and intratesticular testosterone and pituitary bioactive chorionic gonadotropin (bioCG) were measured. Testicular development was assessed by ultrasonography, histology, and flow cytometry. Three consecutive blood samples revealed extreme fluctuations in testosterone concentrations, suggesting an erratic secretion. Age-related changes in serum testosterone and pituitary bioCG concentrations were observed. Intratesticular androgens (ITAs) showed high fluctuations within groups at all ages and were high in some animals by 21 wk. Unexpectedly, no correlation between pituitary bioCG and serum testosterone or ITAs was found, but these parameters significantly correlated with testicular weight and volume. These observations were consistent a dependence on the testis growth on bioCG. Unfortunately, the low serum levels of bioCG were not measurable in this study. At 43 wk, the animals reached puberty. At 52 wk of age, animals attained maximum body and epididymal weights and qualitatively normal spermatogenesis, but testes continued growing, reaching a maximum of all parameters at 70 wk of age, without further major changes at the age of 116 wk. It is concluded that (1) gonadal activation is evident at wk 21, (2) the male marmoset reaches the pubertal threshold around 43 wk of age, attains qualitative parameters at 52 wk, matures further to sexual maturity at 70 wk, and (3) serum testosterone and ITAs are highly variable without any identifiable correlation with pituitary bioCG.  相似文献   
140.
Onion slices were dried under different processing conditions applying infrared radiation assisted by hot air. Drying temperature, slice thickness, inlet air temperature and air velocity were varied to study the drying behavior. Thin layer models such as Page, modified Page, Fick's and Exponential models, which are used to describe the drying kinetics of food materials, were tested for the combination mode drying. The linear plots for Page and modified Page models gave a better fit (R2=0.980-0.995) over the other two models (R2=0.767-0.933). A combined regression equation developed to predict the drying parameters (k and n) for all the four models gave a fairly good fit (R2=0.852-0.989). The modified Page model gave better predictions for drying characteristics over the other models.  相似文献   
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