According to the comprehensive tests on the rising height of capillary water for seven kinds of differ- ent coarse grained soil by use of the method of standpipe, the relationship between the rising height of capillar...According to the comprehensive tests on the rising height of capillary water for seven kinds of differ- ent coarse grained soil by use of the method of standpipe, the relationship between the rising height of capillary water and time was obtained, and the influencing factors and rules were analyzed. The data of the steady rising height of capillary water were obtained, and the regression equation of coarse grained soil on steady height and physical indexes (effective grain dl0 and porosity n) was found. Compared with Hazen's and other expressions that could estimate the steady height of capillary water of coarse grained soil, the proposed method is satisfactory and the defects of the latter were pointed out.展开更多
This study aims at investigating the AIS (Agricultural Information System) in Hamedan province, Iran, benefiting from the list of criteria for well functioning AISs that were identified in earlier researches. For th...This study aims at investigating the AIS (Agricultural Information System) in Hamedan province, Iran, benefiting from the list of criteria for well functioning AISs that were identified in earlier researches. For this purpose, a survey method with multi-stage stratified random sampling technique was used to select 31 agricultural researchers, and 62 extension workers in the province. The data were acquired by questionnaire and structured interviews. The instrument for data collection was subjected to pre-testing, validation and reliability tests. The results of the factor analysis revealed that the criteria could be categorized into four overarching groups based on their inter-correlation. The analysis of mentioned criteria in Hamedan province AIS showed less efficiency and effectiveness than studies conducted in other areas. But among these, two desirable criteria existed. It is recommended that the ecological knowledge system (EKS) should be integrated with AIS, and some ecological and sustainable development criteria should be added to the existing ones.展开更多
The transformation profiles of polycyclic aromatic hydrocarbons (PAHs) by pure laccases from Trametes versicolor and Pycnoporus sanguineus, and the optimal reaction conditions (acetonitrile concentration, pH, tempe...The transformation profiles of polycyclic aromatic hydrocarbons (PAHs) by pure laccases from Trametes versicolor and Pycnoporus sanguineus, and the optimal reaction conditions (acetonitrile concentration, pH, temperature and incubation time) were determined. Anthracene was the most transformable PAH by both laccases, followed by benzo[a]pyrene, and benzo[a]anthracene. Laccase-mediator system (LMS) could not only improve the PAH oxidation but also extend the substrate types compared to laccase alone. 5e/0 or 10~ (v/v) of acetonitrile concentration, pH 4, temperature of 40 ~C, and incubation time of 24 h were most favorable for anthracene oxidation by laccase from T. versicolor or P. sanguineus. The gas chromatography-mass spectrometry analysis indicated that 9,10- anthraquinone was the main product of anthracene transformed by laccase from T. versicolor. Microtox test results showed that both anthracene and its laccase-transformation products were not acute toxic compounds, suggesting that laccase-treatment of anthracene would not increase the acute toxicity of contaminated site.展开更多
文摘According to the comprehensive tests on the rising height of capillary water for seven kinds of differ- ent coarse grained soil by use of the method of standpipe, the relationship between the rising height of capillary water and time was obtained, and the influencing factors and rules were analyzed. The data of the steady rising height of capillary water were obtained, and the regression equation of coarse grained soil on steady height and physical indexes (effective grain dl0 and porosity n) was found. Compared with Hazen's and other expressions that could estimate the steady height of capillary water of coarse grained soil, the proposed method is satisfactory and the defects of the latter were pointed out.
文摘This study aims at investigating the AIS (Agricultural Information System) in Hamedan province, Iran, benefiting from the list of criteria for well functioning AISs that were identified in earlier researches. For this purpose, a survey method with multi-stage stratified random sampling technique was used to select 31 agricultural researchers, and 62 extension workers in the province. The data were acquired by questionnaire and structured interviews. The instrument for data collection was subjected to pre-testing, validation and reliability tests. The results of the factor analysis revealed that the criteria could be categorized into four overarching groups based on their inter-correlation. The analysis of mentioned criteria in Hamedan province AIS showed less efficiency and effectiveness than studies conducted in other areas. But among these, two desirable criteria existed. It is recommended that the ecological knowledge system (EKS) should be integrated with AIS, and some ecological and sustainable development criteria should be added to the existing ones.
基金Supported by the National High-Tech R&D Program of China(No.2007AA061101)the Key Laboratory of Soil Environment and Pollution Remediation,Institute of Soil Science,Chinese Academy of Sciencesthe Zhejiang Provincial Natural Science Foundation of China(No.Y5110147)
文摘The transformation profiles of polycyclic aromatic hydrocarbons (PAHs) by pure laccases from Trametes versicolor and Pycnoporus sanguineus, and the optimal reaction conditions (acetonitrile concentration, pH, temperature and incubation time) were determined. Anthracene was the most transformable PAH by both laccases, followed by benzo[a]pyrene, and benzo[a]anthracene. Laccase-mediator system (LMS) could not only improve the PAH oxidation but also extend the substrate types compared to laccase alone. 5e/0 or 10~ (v/v) of acetonitrile concentration, pH 4, temperature of 40 ~C, and incubation time of 24 h were most favorable for anthracene oxidation by laccase from T. versicolor or P. sanguineus. The gas chromatography-mass spectrometry analysis indicated that 9,10- anthraquinone was the main product of anthracene transformed by laccase from T. versicolor. Microtox test results showed that both anthracene and its laccase-transformation products were not acute toxic compounds, suggesting that laccase-treatment of anthracene would not increase the acute toxicity of contaminated site.