According to the distribution characteristics of traffic congestion in time and space, a measure index system of urban traffic congestion is set up based on the spatial and temporal distribution. Based on the analysis...According to the distribution characteristics of traffic congestion in time and space, a measure index system of urban traffic congestion is set up based on the spatial and temporal distribution. Based on the analysis of the main characteristics of traffic congestion and the generation process of traffic congestion, the measure model for urban traffic congestion is constructed by the value function. Moreover, based on the measure values of traffic congestion in urban road networks with defined different levels, a method to prevent and control traffic congestion is designed. The application results confirm that the proposed method is feasible in comprehensive measures for urban traffic congestion and they are consistent with the results of other methods. The measuring results can therefore reflect the actual situation. The comprehensive measure model is scientific and the process is simple, and it has wide application prospects and practical value.展开更多
The pH values of soils collected from 30 different districts of Al-Madinah Al-Munawarah province were measured using an Electric pH meter. The pH values revealed （27%） a slight to （60%） medium alkalinity ranged be...The pH values of soils collected from 30 different districts of Al-Madinah Al-Munawarah province were measured using an Electric pH meter. The pH values revealed （27%） a slight to （60%） medium alkalinity ranged between： 7.17-9.45 （pH 8.13 ± 0.13） The alkalinity is attributed to scanty rainfall and deep underground waters as well as deposition of high air pollution contents at Al-Madinah Al-Munawarah. Such soil alkalinity is not optimum to growth of arable/lea-grassland but only for limited cultivation i.e. date palms in comparison with Northwestern and Southwestern sectors of KSA. It is recommended to carry out similar soil evaluation of other parts of KSA involving more measurements i.e. ionic concentration, nutrient levels, micro-flora and to laundry these lands to lower soil＇spHs and to increase its fertility.展开更多
The world is experiencing a growing shortage of raw materials which is especially severe in the energy sector and being worsened by the unfavorable environmental impact of a consumerist cultttre revolving around the e...The world is experiencing a growing shortage of raw materials which is especially severe in the energy sector and being worsened by the unfavorable environmental impact of a consumerist cultttre revolving around the exploitation of non-renewable resources. In this work, the calorific value and chemical composition of liquors resulting from the autohydrolysis of six different lignocellulosic materials was determined （Eucalyptus globulus, Arundo donax, Leucaena diversifolia, Paulownia fortunei, Sunflower stalks and Chamaecytisus proliferus） and was assessed for the obtainment of energy, sugars and other chemical products by using of integral fractionation based on autohydrolysis. Autohydrolysis processes have been considered interesting in the case of timber species studied compared with herbaceous species with variations in the extraction of the xylan fraction at 180℃ between 19.68% for Eucalyptus globulus and 36.79% for Leucaena diversifolia and 200℃ between 57.86% for Paulawniafortunei and 79.13 % for Chamaecytisusproliferus. In general, all materials show a solid fraction ＂more energy＂ from the hydrolysis to 200℃ than 180℃ and raw materials. It is interesting as the potential economy valuation of the liquid fractions of the hydrolysis, the solid waste recovery present more energetic profitability.展开更多
基金The National Natural Science Foundation of China(No.51178157)
文摘According to the distribution characteristics of traffic congestion in time and space, a measure index system of urban traffic congestion is set up based on the spatial and temporal distribution. Based on the analysis of the main characteristics of traffic congestion and the generation process of traffic congestion, the measure model for urban traffic congestion is constructed by the value function. Moreover, based on the measure values of traffic congestion in urban road networks with defined different levels, a method to prevent and control traffic congestion is designed. The application results confirm that the proposed method is feasible in comprehensive measures for urban traffic congestion and they are consistent with the results of other methods. The measuring results can therefore reflect the actual situation. The comprehensive measure model is scientific and the process is simple, and it has wide application prospects and practical value.
文摘The pH values of soils collected from 30 different districts of Al-Madinah Al-Munawarah province were measured using an Electric pH meter. The pH values revealed （27%） a slight to （60%） medium alkalinity ranged between： 7.17-9.45 （pH 8.13 ± 0.13） The alkalinity is attributed to scanty rainfall and deep underground waters as well as deposition of high air pollution contents at Al-Madinah Al-Munawarah. Such soil alkalinity is not optimum to growth of arable/lea-grassland but only for limited cultivation i.e. date palms in comparison with Northwestern and Southwestern sectors of KSA. It is recommended to carry out similar soil evaluation of other parts of KSA involving more measurements i.e. ionic concentration, nutrient levels, micro-flora and to laundry these lands to lower soil＇spHs and to increase its fertility.
文摘The world is experiencing a growing shortage of raw materials which is especially severe in the energy sector and being worsened by the unfavorable environmental impact of a consumerist cultttre revolving around the exploitation of non-renewable resources. In this work, the calorific value and chemical composition of liquors resulting from the autohydrolysis of six different lignocellulosic materials was determined （Eucalyptus globulus, Arundo donax, Leucaena diversifolia, Paulownia fortunei, Sunflower stalks and Chamaecytisus proliferus） and was assessed for the obtainment of energy, sugars and other chemical products by using of integral fractionation based on autohydrolysis. Autohydrolysis processes have been considered interesting in the case of timber species studied compared with herbaceous species with variations in the extraction of the xylan fraction at 180℃ between 19.68% for Eucalyptus globulus and 36.79% for Leucaena diversifolia and 200℃ between 57.86% for Paulawniafortunei and 79.13 % for Chamaecytisusproliferus. In general, all materials show a solid fraction ＂more energy＂ from the hydrolysis to 200℃ than 180℃ and raw materials. It is interesting as the potential economy valuation of the liquid fractions of the hydrolysis, the solid waste recovery present more energetic profitability.
