The assessment of nanomechanical properties of a single amyloid fibril in a confined space provides important information for understanding the role of fibrils in a cell microenvironment. In this study, the structure ...The assessment of nanomechanical properties of a single amyloid fibril in a confined space provides important information for understanding the role of fibrils in a cell microenvironment. In this study, the structure and nanomechanical properties of different fibrils formed in water nanofilms on mica surface are carefully investigated by using the new atomic force microscopy imaging mode-peak force quantitative nanomechanics （PF-QNM）. We find that two types of fibrils with different morphologies are formed in water nanofilm on mica. The compression elasticities of these two types of fibrils are 3.9±0.9 and 2.5±0.6 GPa, respectively. The remarkable difference is possibly due to the structural discrepancy in two types of fibrils.展开更多
The general form of the north-branch of the Changjiang River mouth has changed much as a result of the change of the main stream lines of the Nantong reach of the Changjiang River and the influence of human activities...The general form of the north-branch of the Changjiang River mouth has changed much as a result of the change of the main stream lines of the Nantong reach of the Changjiang River and the influence of human activities since 1915. By the 1930s, the main stream lines of the Nantong reach of the Changjiang River has shifted to the Tongzhou Bar west channel. The north-branch at the Changjiang River mouth has become atrophic because of Tongzhou Bar east channel's deposition. After 1958, Toughal Bar and Jiangxin Bar were exploited. And in 1970, the north channel of Jiangxin Bar was blocked up. All these things make the water of the north-branch more difficult to pass through. It leads to the decline of the total discharge percentage of the north-branch. And it causes the rising tide to go back to the south-branch. However, since 1978, with the development of Tongzhou Bar east channel and its left bank being scoured, the water amount of the north-branch has been increasing. And the water,load and salt of going back to the south-branch has been becoming less.展开更多
Two approaches, named pressure filtration (PF) and vaporization dewatering (VD), for qualitative and quantitative analysis of the water forms were presented. The principle of VD is that with the process of heating, th...Two approaches, named pressure filtration (PF) and vaporization dewatering (VD), for qualitative and quantitative analysis of the water forms were presented. The principle of VD is that with the process of heating, the free water, surface water and capillary water are in turn vaporized at different rates, then the turning points of the rates are determined and the quantitative analysis can be made. Some experiments with suspension of water and CaCO 3 powder were given and discussed by applying the vaporization dewatering approach. [展开更多
The paper discusses assessment of various chemical constituents present in groundwater besides morphology, and land form characteristics of twin micro-watersheds (viz., Melekote and Rajaghatta) Dodballapur Taluk, (Kar...The paper discusses assessment of various chemical constituents present in groundwater besides morphology, and land form characteristics of twin micro-watersheds (viz., Melekote and Rajaghatta) Dodballapur Taluk, (Karnataka) coming under semi-arid climatic zone. Farmers who are mainly depending on agricultural yields for their living are disappointed due to vagaries of monsoons and undependable rainfall. This is particularly so in arid and semi-arid regions. These regions suffer from water scarcity, soil degradation, low crop yield, high soil erosion and gradual depletion of soil fertility. All these factors culminate in planning for conservation and storage of water in small watersheds for future needs, i.e., during drought conditions. In many areas, it is observed that the water table levels are declining resulting in problems of increased concentration of solutes and deterioration of groundwater quality. All aspects of hydrological studies are covered in relation to watershed management in order to formulate strategies for sustainable agricultural development. Morphometry, landform and topography play an important role in understanding the hydrological response of any watershed. Quantitative morphometric analysis has been carried out on the watershed along with landform and topographical study.展开更多
Based on field detected water quality data, the distribution characteristics of different forms of nitrogen in a reservoir as drinking water source in Dongguan, which locates at the Pearl River Delta of China, have be...Based on field detected water quality data, the distribution characteristics of different forms of nitrogen in a reservoir as drinking water source in Dongguan, which locates at the Pearl River Delta of China, have been analyzed in order to provide theoretical bases for prevention and reduction of eutrophication. The analyzed results show that nitrogen forms in the influent area of the reservoir are given priority to ammonia nitrogen and nitrate nitrogen, whose proportion is more than 45% respectively, and this is probably caused by the pollution of inflow water quality;but in the effluent area, the forms are given priority to nitrate nitrogen, whose proportion is as high as 96% and above;also the proportion of ammonia nitrogen drops by more than 80% during the process from the influent area to the effluent area, and this shows that the natural process of nitrification and denitrification can be well accomplished in the reservoir. We recommend here that to reduce the input amount of ammonia nitrogen and organic nitrogen into the reservoir is the most efficient way to prevent or mitigate eutrophication of water body.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 11474173the Natural Science Foundation of Zhejiang Province under Grant Nos LY14A040006 and LQ14F040002+1 种基金the Ningbo Natural Science Foundation under Grant Nos2014A610202 and 2014A610149the K.C.Wong Magna Fund in Ningbo University
文摘The assessment of nanomechanical properties of a single amyloid fibril in a confined space provides important information for understanding the role of fibrils in a cell microenvironment. In this study, the structure and nanomechanical properties of different fibrils formed in water nanofilms on mica surface are carefully investigated by using the new atomic force microscopy imaging mode-peak force quantitative nanomechanics （PF-QNM）. We find that two types of fibrils with different morphologies are formed in water nanofilm on mica. The compression elasticities of these two types of fibrils are 3.9±0.9 and 2.5±0.6 GPa, respectively. The remarkable difference is possibly due to the structural discrepancy in two types of fibrils.
文摘The general form of the north-branch of the Changjiang River mouth has changed much as a result of the change of the main stream lines of the Nantong reach of the Changjiang River and the influence of human activities since 1915. By the 1930s, the main stream lines of the Nantong reach of the Changjiang River has shifted to the Tongzhou Bar west channel. The north-branch at the Changjiang River mouth has become atrophic because of Tongzhou Bar east channel's deposition. After 1958, Toughal Bar and Jiangxin Bar were exploited. And in 1970, the north channel of Jiangxin Bar was blocked up. All these things make the water of the north-branch more difficult to pass through. It leads to the decline of the total discharge percentage of the north-branch. And it causes the rising tide to go back to the south-branch. However, since 1978, with the development of Tongzhou Bar east channel and its left bank being scoured, the water amount of the north-branch has been increasing. And the water,load and salt of going back to the south-branch has been becoming less.
文摘Two approaches, named pressure filtration (PF) and vaporization dewatering (VD), for qualitative and quantitative analysis of the water forms were presented. The principle of VD is that with the process of heating, the free water, surface water and capillary water are in turn vaporized at different rates, then the turning points of the rates are determined and the quantitative analysis can be made. Some experiments with suspension of water and CaCO 3 powder were given and discussed by applying the vaporization dewatering approach. [
文摘The paper discusses assessment of various chemical constituents present in groundwater besides morphology, and land form characteristics of twin micro-watersheds (viz., Melekote and Rajaghatta) Dodballapur Taluk, (Karnataka) coming under semi-arid climatic zone. Farmers who are mainly depending on agricultural yields for their living are disappointed due to vagaries of monsoons and undependable rainfall. This is particularly so in arid and semi-arid regions. These regions suffer from water scarcity, soil degradation, low crop yield, high soil erosion and gradual depletion of soil fertility. All these factors culminate in planning for conservation and storage of water in small watersheds for future needs, i.e., during drought conditions. In many areas, it is observed that the water table levels are declining resulting in problems of increased concentration of solutes and deterioration of groundwater quality. All aspects of hydrological studies are covered in relation to watershed management in order to formulate strategies for sustainable agricultural development. Morphometry, landform and topography play an important role in understanding the hydrological response of any watershed. Quantitative morphometric analysis has been carried out on the watershed along with landform and topographical study.
文摘Based on field detected water quality data, the distribution characteristics of different forms of nitrogen in a reservoir as drinking water source in Dongguan, which locates at the Pearl River Delta of China, have been analyzed in order to provide theoretical bases for prevention and reduction of eutrophication. The analyzed results show that nitrogen forms in the influent area of the reservoir are given priority to ammonia nitrogen and nitrate nitrogen, whose proportion is more than 45% respectively, and this is probably caused by the pollution of inflow water quality;but in the effluent area, the forms are given priority to nitrate nitrogen, whose proportion is as high as 96% and above;also the proportion of ammonia nitrogen drops by more than 80% during the process from the influent area to the effluent area, and this shows that the natural process of nitrification and denitrification can be well accomplished in the reservoir. We recommend here that to reduce the input amount of ammonia nitrogen and organic nitrogen into the reservoir is the most efficient way to prevent or mitigate eutrophication of water body.
