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101.
Environmental Science and Pollution Research - No-till wheat is gaining popularity in rice-based cropping system as it provides a better chance for timely planting of wheat, management of crop...  相似文献   
102.
Dilute sulfuric acid pretreatment was used to improve the biomethane production from wheat plant (WP) via mesophilic anaerobic digestion. The pretreatments were performed at 121°C for different time durations of 10, 30, 60, and 120 min. The maximum methane yield of 302.4 mL/g volatile solids (VS) was obtained after the pretreatment for 120 min, which was 15.5% higher than that of the untreated WP. The highest amounts of lignin removal (15.2%) and xylan degradation (91.5%) were also achieved after this pretreatment. The pretreatment for 60 min enhanced the methane yield by 8.9%, while the pretreatments for 10 and 30 min had no positive effects on the methane yield. All of the pretreatments significantly removed the hemicelluloses. Moreover, the qualitative analysis of the untreated and pretreated WP structure showed significant reduction in the crystallinity index accompanied by the destruction of surface layers of WP structure after pretreatment.  相似文献   
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104.
In this research tannic acid was used to prepare soy-based adhesives for making plywood and fiber board. The different resin formulations were analyzed by Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and its derivative as a function of temperature (DTG) and Fourier Transform Infra-red (FTIR) spectroscopy. The results showed that the addition of tannic acid to soy-based adhesive decreased soy-based adhesive viscosity and its pH. The DSC analysis showed that the denaturation temperature of soy-based adhesives decrease by adding tannic acid. The TGA and DTG curves showed that the thermal degradation of soy flour starts above 146 °C. The FTIR spectroscopy results also showed that the soy flour amino acids appeared to react well with tannic acid. Furthermore, delamination and shear strength test results showed the good water resistance of plywood bonded with soy-based tannic acid-modified adhesive. The mechanical and physical properties such as MOR, MOE, IB, and water resistance of fiberboard were improved, by adding tannic acid to the soy-based adhesive.  相似文献   
105.
Objective. This study was conducted to assess hazards faced by elementary workers. Methods. A questionnaire survey and a respiratory function test (spirometry) were carried out on 150 respondents. Results. Major hazards identified related to sharp objects, heavy weight lifting, thermally harsh conditions, working at height, whole body vibration, chemicals, pathogens, increased noise levels and confined space entry. Workers suffered from upper and lower respiratory disorder symptoms, digestive problems, optical and musculoskeletal issues, etc. Spirometric measurement showed obstructive lung disorders to be highest among construction workers (CW) (48%) followed by sanitation workers (SW) (32%) and solid waste pickers (SWP) (28%). Restrictive lung pattern was dominant among SW (56%) followed by SWP (46%) and CW (42%). The observed FEV1/FVC in diseased SWP, SW and CW ranged from 51 to 96%, from 52 to 98% and from 31 to 99% respectively while observed mean FEV1 was 2.15, 1.79 and 1.70 L, respectively. Conclusion. The study findings show that occupational exposure can significantly influence respiratory system impairment and contribute to other ailments among elementary workers. The study recommends use of appropriate protective equipment and regular medical examination for early recognition of any health risk so that timely interventions for effective management may be undertaken.  相似文献   
106.
Environmental Science and Pollution Research - The livelihoods of poor people living in rural areas of Indus Basin Irrigation System (IBIS) of Pakistan depend largely on irrigated agriculture....  相似文献   
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108.
Zilouei H  Guieysse B  Mattiasson B 《Chemosphere》2008,72(11):1788-1794
An organic-aqueous two-liquid-phase partitioning system was developed to degrade high concentrations of pentachlorophenol (PCP). Dioctyl sebacate was selected among 12 non-aqueous phases as the most suitable solvent to control the delivery of PCP to the aqueous phase for being non-biodegradable and biocompatible. In shake-flask experiments, the two-phase system was able to support the removal of 1g PCP l(-1) of total liquid phase. The performance of the two-liquid phase partitioning system (TLPPS) in shake-flask was evaluated under different conditions. At the initial biomass concentrations of 7, 25, and 58 mg dry weight l(-1), the volumetric removal rates of PCP obtained were 25.7+/-0.5, 32.1+/-0.1, and 39.3+/-2.9 mg PCP l(-1)h(-1), respectively. Higher performance was observed at lower organic-aqueous phase ratios (16% and 28%) than higher ones (37% and 44%). In a 2-l TLPPS, the degradation of 10 g PCP was completed in less than 100 h at a total volumetric rate of 142 mg l(-1) h(-1). Kinetics study using Monod model showed that compared to monophasic systems, the biphasic system significantly enhanced the maximum specific growth rate and PCP removal rate. Results of this biphasic system showed no accumulation of unknown by-product(s) which has been reported for physical-pretreatment or high-performance biphasic systems of PCP degradation.  相似文献   
109.
Numerical and experimental analyses were applied to carbon monoxide (CO) concentration dispersion to monitor air quality in an enclosed residential complex parking area in Tehran. Firstly, the parking area was preliminary assessed through verifying the characteristics of the problem including the geometry and boundary conditions. Then, proportion of vehicular exhaust emissions was estimated and eventually experimental and numerical analyses were performed. In order to perform numerical calculation, a three-dimensional model was created to numerically simulate the enclosed residential complex parking area by FLUENT software that solves flow governing equations with finite volume method. In FLUENT, species model was selected to assess the dispersion of CO in flow domain. In experimental analysis, CO concentration was measured using sampling bags with a volume of 10 l in 4 min at 6 different points. The sample air was drawn into sampling bags by electric pumps. The findings show that the maximum amount of CO concentration is above the permissible standard recommended by the World Health Organization. Pollutant accumulation was significant in confined areas. In the place where openings exist, the level of accumulation was lower than other areas. The findings obtained from numerical simulation are in complete accord with experimental results.  相似文献   
110.
Environmental Science and Pollution Research - The number and production capacities of greenhouse farms have been increased across the globe, driven by an effort for addressing food security...  相似文献   
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