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131.
依据田间实测资料,分析了南亚热带丘陵赤红壤-果树-大气连续体中的能量变化及其分布规律、结果表明,土壤基质势的年度变化特征说明南亚热带丘陵赤红壤存在明显的湿季和旱季.果树叶水势随土壤基质势、大气水势、气温及大气相对湿度的变化而变化,荔枝、龙眼叶水势的变化比芒果叶水势的变化大.以荔枝、芒果和龙眼作为供试植物,水分从土壤到达植物根表皮、进入根系并通过植物茎到达叶片,其能量降低分别约为0.9063~1.7428、0.2818~0.6979和0.2904~1.8707MPa;水分从叶部汽化扩散到大气中,其能量降低分别达15.1491~57.3669、15.4491~58.4036和14.5824~56.9536MPa,说明水流在南亚热带丘陵赤红壤-果树-大气连续体中运移时,其能量主要消耗在由叶部到大气这一环节上。 相似文献
132.
Jianxin Shou Huaping Dong Jianfa Li Jiaxing Zhong Saijun Li Jinhong Lü Yimin Li 《Environmental science and pollution research international》2016,23(19):19156-19163
Biochars’ properties will change after application in soil due to the interactions with soil constituents, which would then impact the performance of biochars as soil amendment. For a better understanding on these interactions, two woody biochars of different surface areas (SA) were physically treated with aluminum oxide (Al-oxide) to investigate its potential influence on biochars’ sorption property. Both the micropore area and mesopore (17~500 Å in diameter) area of the low-SA biochar were enhanced by at least 1.5 times after treatment with Al-oxide, whereas the same treatment did not change the surface characteristics of the high-SA biochar due partly to its well-developed porosity. The enhanced sorption of the pesticide isoproturon to the Al-oxide-treated low-SA biochar was observed and is positively related to the increased mesopore area. The desorption hysteresis of pesticide from the low-SA biochar was strengthened because of more pesticide molecules entrapped in the expanded pores by Al-oxide. However, no obvious change of pesticide sorption to the high-SA biochar after Al-oxide treatment was observed, corresponding to its unchanged porosity. The results suggest that the influence of Al-oxide on the biochars’ sorption property is dependent on their porosity. This study will provide valuable information on the use of biochars for reducing the bioavailability of pesticides. 相似文献
133.
Zhong Jun Li Si-liang Tao Faxiang Ding Hu Liu Jing 《Environmental science and pollution research international》2017,24(23):19126-19137
Environmental Science and Pollution Research - Feedback between hydrologic variations and chemical weathering is thought to play a crucial role in modulating global carbon cycling. The mechanisms... 相似文献
134.
135.
矿井通风系统模糊可靠性研究 总被引:2,自引:1,他引:2
定义模糊可靠度为一个服从正态分布的模糊数,并以模糊数作为通风系统的各风路可靠度,进而提出了矿井通风系统的模糊可靠度计算方法。同时在置信水平上,确定矿井通风系统的普通可靠度置信区间。若=1,则模糊可靠度计算转化为可靠度计算。 相似文献
136.
自然灾害风险损失等评估的初步研究 总被引:3,自引:1,他引:3
在综述国内外自然灾害风险损失评估研究成果的基础上,运用归一化原理,对灾害风险度和灾害损失度的相对等级进行了划分,提出了单一灾种和复合灾种灾害风险损失度相对等级的划分方案和划分方法,然后依据不同灾种在时间上和空间上的叠加性以及机理上的关联性,对区域自然灾害风险损失等级评估方法和评估体系进行了初步探讨。 相似文献
137.
Qi Zhong Daping Li Yong Tao Xiaomei Wang Xiaohong He Jie Zhang Jinlian Zhang Weiqiang Guo Lan Wang 《Waste management (New York, N.Y.)》2009,29(4):1347-1353
Ex situ nitrification and sequential in situ denitrification represents a novel approach to nitrogen management at landfills. Simultaneous ammonia and organics removal was achieved in a continuous stirred tank reactor (CSTR). The results showed that the maximum nitrogen loading rate (NLR) and the maximum organic loading rate (OLR) was 0.65 g N l?1 d?1 and 3.84 g COD l?1 d?1, respectively. The ammonia and chemical oxygen demand (COD) removal was over 99% and 57%, respectively. In the run of the CSTR, free ammonia (FA) inhibition and low dissolved oxygen (DO) were found to be key factors affecting nitrite accumulation. In situ denitrification was studied in a municipal solid waste (MSW) column by recalculating nitrified leachate from CSTR. The decomposition of MSW was accelerated by the recirculation of nitrified leachate. Complete reduction of total oxidized nitrogen (TON) was obtained with maximum TON loading of 28.6 g N t?1 TS d?1 and denitrification was the main reaction responsible. Additionally, methanogenesis inhibition was observed while TON loading was over 11.4 g N t?1 TS d?1 and the inhibition was enhanced with the increase of TON loading. 相似文献
138.
本文研究了植稻前淹水时间长短对土壤物理性质和粘闭作用的影响。结果表明,淹水可以显著地降低土壤强度,但土壤抗穿透力并不随淹水时间的延长而进一步明显下降;延长淹水时间,可以促进土壤粉粒和粘粒的分散,但土壤粘闭胼形成的有效粘闭层厚度以及粘闭后表层土壤强度的降低、主要受所使用的粘闭机具的影响,而与淹水时间的长短无关。因此,过分地延长淹水时间的措施,在生产实践上的意义并不大。 相似文献
139.
Hu Yiqin Jiang Hongying Zhong Zhangqi 《Environmental science and pollution research international》2020,27(10):10506-10519
Environmental Science and Pollution Research - Chinese industrial structure is characterized by a large proportion of industries with high energy consumption and high pollution, such as coal,... 相似文献
140.
钻井污水是一种棕黑色的多组分复杂体系,含有大量粘土粒子、电解质、少量浮油和油田处理剂,基本上属于胶体体系。ξ电势是胶体的一个重要性质,试验中研究测试了几种常用无机絮凝剂处理钻井污水时ξ电势的变化,根据ξ电势的大小及等电点时絮凝剂的用量对其进行了筛选。 相似文献