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11.
The increasing availability of multi‐scale remotely sensed data and global weather datasets is allowing the estimation of evapotranspiration (ET) at multiple scales. We present a simple but robust method that uses remotely sensed thermal data and model‐assimilated weather fields to produce ET for the contiguous United States (CONUS) at monthly and seasonal time scales. The method is based on the Simplified Surface Energy Balance (SSEB) model, which is now parameterized for operational applications, renamed as SSEBop. The innovative aspect of the SSEBop is that it uses predefined boundary conditions that are unique to each pixel for the “hot” and “cold” reference conditions. The SSEBop model was used for computing ET for 12 years (2000‐2011) using the MODIS and Global Data Assimilation System (GDAS) data streams. SSEBop ET results compared reasonably well with monthly eddy covariance ET data explaining 64% of the observed variability across diverse ecosystems in the CONUS during 2005. Twelve annual ET anomalies (2000‐2011) depicted the spatial extent and severity of the commonly known drought years in the CONUS. More research is required to improve the representation of the predefined boundary conditions in complex terrain at small spatial scales. SSEBop model was found to be a promising approach to conduct water use studies in the CONUS, with a similar opportunity in other parts of the world. The approach can also be applied with other thermal sensors such as Landsat.  相似文献   
12.
Occupational exposure is unregulated in developing countries like India, and becoming the most common cause of disease of environmental origin. The present study was aimed to investigate the effects of occupational exposure on plasma lipid profiles, and risk of cardiovascular diseases. A total of 79 human volunteers were included in the study. Control subjects were healthy housewives of Karimnagar, India. Occupationally exposed individuals included different occupational workers like petrol station attendants, battery chargers, drivers, welders, pesticide-exposed workers, painters, and auto mechanics. These subjects were shown to be chronic occupationally-exposed for at least three years, and neither associated with any other chronic pathological conditions like hypertension or diabetes, nor under any medication other than analgesics during the month preceding the study. Subjects with excessive high or low caloric intake were excluded from the study. Total cholesterol (TC), LDL cholesterol, triglycerides (TG), VLDL cholesterol, LDL/HDL cholesterol, and TC/HDL ratio in these subjects were significantly higher than those in control subjects, whereas HDL cholesterol was not markedly affected. Blood pressure (systolic and diastolic), and other anthropometric parameters (body mass index (BMI), body fat index (BFI), body surface area (BSA)) were not significantly different between groups. Data suggest that chronic occupational exposure increases plasma lipid levels and is thereby associated with cardiovascular complications.  相似文献   
13.
Environmental Chemistry Letters - Developing environmentally benign synthetic protocols such as reaction in water is a major challenge. However, many of the known methods carried out in an...  相似文献   
14.
The destruction and colour removal of methylene blue were carried out by mediated electrochemical oxidation using cerium(IV) mediator in nitric acid medium using two-phase system and was applied for oxidation of organic compound. Organic compounds and mediator were taken in the organic and aqueous phases respectively. The influence of organic solvent type, cerium(III) concentration, dye concentration, stirring speed and temperature were investigated in order to find the optimum conditions of the system to check the removal of COD and colour in the organic phase. The decolourisation followed the pseudo-first order reaction for electrochemically oxidized cerium(IV). The maximum colour removal efficiency of 95% was achieved within 45 min in dichloromethane solvent system. The COD removal efficiency and colour removal rate were increased with increase in temperature and stirring speed.  相似文献   
15.
Jatropha curcas L. (Jatropha) is an important multipurpose tree valued for oil. In India, plans are underway to bring substantial area under this crop for meeting the biofuel requirements of the country. A study was conducted to develop allometric relationships in Jatropha to predict various biomass-related components (above ground and below ground) using easily measurable attributes, viz. collar diameter, tree height, number of branches, crown diameter, and crown depth. Further, it was aimed to establish the reliability of these relationships using an independent dataset obtained from varied management situations. Destructive sampling was carried out during the rainy season of 2011, when Jatropha plants were eight years old. Highly significant allometric relationships (F-values significant at 1% level) were obtained while predicting various biomass components (above, below, and total) using easily measurable attributes with R2 values ranging from 0.89 to 0.98. Of all the predictors, collar diameter exhibited a highly significant relationship with total dry biomass per plant (R2 = 0.97). The allometric relationships developed were validated with an independent dataset. The allometric relationships developed would serve as valuable tools for estimating total dry biomass production and carbon sequestration with reasonable accuracy in Jatropha systems, as they are proposed to be taken up in substantial area in the years to come.  相似文献   
16.
A fuel cell hybrid (FCH) mid-size car is modeled and simulated in Advanced Vehicle Simulator (ADVISOR), the results are compared with 2017 Toyota Mirai Fuel Cell Electric Vehicle (FCEV) to examine the capability of hybridization and compare the fuel economy of the modeled vehicle. The aim of this analysis is to understand the energy interactions of the fuel cell and batteries and to identify an optimal energy management. In the current modeling, the fuel cell power is downsized by 30% with a corresponding increase in the number of battery modules by 50% to compensate the fuel cell power by maintaining the same motor power demand. The Urban Dynamometer Driving Schedule (UDDS) and mountain driving cycle (NREL2VAIL) test cycles are considered to estimate the fuel economy for urban and hill road driving conditions. The FCH mid-size car achieves better performance in terms of acceleration and equivalent fuel economy in comparison with 2017 Toyota Mirai FCEV. The effectiveness of the optimal energy management of the hybrid FC/battery powertrain performance is better and validated with the 2017 Toyota Mirai FCEV.  相似文献   
17.
A numerical model for simultaneous heat and mass transfer was developed for solar drying of spherical objects and the object considered is green peas. Solar collector outlet temperature is assumed as drying chamber temperature and justified through energy balance equations. Assumptions are imposed on heat and mass transfer governing equations without losing the physics of the problem. Discretization is performed by finite difference method with implicit scheme. To generalize, the governing equation and boundary conditions are non-dimensionalized. The set of finite difference equations was solved by Tridiagonal Matrix Algorithm and a computer code in MATLAB was developed to solve them. The drying curves showed two stages of drying, initial, and secondary drying stage. At all drying temperatures and drying time, the center moisture was maximum and it was minimum at the boundary. A percentage of 85.67 surface moisture content and 25.33% center moisture was eliminated in the first 1 hr at 348 K. The product should be dried up to 7.45, 4.74, and 3.74 hr at air drying temperatures of 318, 333, and 348 K respectively, to maintain 10% of the product’s initial moisture content. The result is compared with the experimental result from literature and they are found to be in good agreement.  相似文献   
18.
The speciation and distribution of Co in soils is poorly understood. This study was conducted using x-ray absorption spectroscopy (XAS) techniques to examine the influence of soluble cobalt in the +2 oxidation state (Co[II]) aging, submergence-dried cycling, and the presence of in vivo rice roots on the speciation and distribution of added Co(II) in soils. In the aging and submerged-dried cycling studies, Co was found to be associated with Mn oxide fraction (23 to 100% of total Co) and Fe oxide fractions (0 to 77% of total Co) of the soils as either Co(II) species or a mixed Co(II), and Co in the +3 oxidation state (Co[III]) species. The surface speciation of Co in the Mn oxide fraction suggests an innersphere complex was present and the speciation of Co in the Fe oxide fraction was an innersphere surface complex. The in vivo root box experiments showed similar Co speciation in the Mn oxide fraction (13 to 76% of total Co) as the aging and submerged-dried cycling studies. However, the Fe oxide fraction of the soil was unimportant in Co retention. A significant amount (24 to 87% of total Co) of the Co in root box treatments was identified as a Co precipitate. The importance of this finding is that in the presence of rice roots, the Co is redistributed to a Co precipitate. This work confirmed earlier macroscopic work that Mn oxides are important in the sequestration of Co in soils and the influence of roots needs to be taken into account when addressing Co speciation. The information gained from this study will be used to improve models to predict the lability and hence the availability of Co in terrestrial environments.  相似文献   
19.
Health issues induced by mosquito illnesses highlight the need for effective control. Here, we developed an efficient carbon-dot-silver nanohybrid to control Anopheles stephensi and Culex quinquefasciatus mosquito species. The nanohybrid was synthesized using a thermal method without addition of any toxic-reducing agent. Monohybrids are found within the ranges of 2–6 nm for carbon-dot and 10–35 nm for silver nanoparticles with uniform distribution. The uniformly dispersed nanohybrid solutions show excellent larvicidal activity within the concentration range of 0.5–1.0 ppm. Morphological studies evidence the presence of strong bonds between nanohybrid and sulphur- or phosphorus-containing compounds such as proteins and DNA present in the larval body. This explains tissue damage at very low concentrations of nanohybrid. Therefore, this nanoweapon has high potential for field applications.  相似文献   
20.
Novel semi-interpenetrating network (semi-IPN) hydrogels based on biodegradable chitosan and poly(N-isopropylacrylamide-co-2-acrylamido-2-methyl-1-propanesulfonic acid) were prepared by free radical addition polymerization. Fourier transform infrared spectra and scanning electron microscopy were used to characterize the semi-IPN hydrogels and the results showed that chitosan and poly(N-isopropylacrylamide-co-2-acrylamide-2-methyl-1-propanesulfonic acid) semi-IPN hydrogels were coupled by the interaction of the functional groups present in NIPAAm, CS and AMPS units. The PNIPAAm and P(NIPAAm-AMPS)/CS hydrogels have lower critical solution temperature and the same was confirmed with the help of differential scanning calorimetry as well as with the temperature dependent swelling curves. The model anti cancer drug, 5-fluorouracil (5-FU) was loaded into the semi-IPN hydrogels, at ambient temperature. The 5-FU loading capacity and release behaviour were investigated with these hydrogels acting as carriers for controlled release. The released 5-FU concentration was calculated with the help of UV spectrophotometer at 266.5?nm.  相似文献   
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