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101.
Kumar A Watal G 《Journal of environmental biology / Academy of Environmental Biology, India》2006,27(3):545-549
The water quality, rate of energy transformation, chemical composition of producers and flow of chemical energy were studied in both feeding river Yamuna and Alwar jheel near Allahabad. As the river Yamuna had high value of alkalinity (210.0 mgl(-1)), conductance (518.0 micromhos), dissolved solids (260.0 mgl(-1)), hardness (162.0 mgl(-1)) and chloride (54.6 mgl(-1)) jheel also showed high values of these parameters. The rate of energy transformation from kinetic radiant energy to chemical energy was very high in the jheel 32,315 Cal m(-2) day(-1) of which 25,620 Cal m(-2) day(-1) was contributed by aquatic plants. Out of 11,764 x 10(4) Kcal ha(-1) yr(-1) total energy fixed in the system, producers stored 7,154 x 10(4) Kcal ha(-1) yr(-1) and the rest was lost as heat of respiration. The pattern of storage of energy was different in two groups of producers and thus most of the energy fixed by phytoplankton was stored as protein (56.2%) and less as carbohydrate (11.7%) while aquatic plants stored more energy as carbohydrate (40.8%) than protein (23.2%). The chemical energy obtained from the system was 1,85,000 Kcal ha(-1) yr(-1) and thus only 0.260% of the chemical energy stored by producers was harvested. The potential chemical energy resource in the jheel was 81.4 x 10(4) Kcal ha(-1) yr(-1) of which only 22.6% was harvested in the jheel and there is enough scope for further enhancement. 相似文献
102.
Singhal RK Preetha J Karpe R Tirumalesh K Kumar SC Hegde AG 《Environment international》2006,32(2):224-228
During this work, size fractionation technique "ultra filtration" is used in speciation studies of trace elements in the coastal sea water. Filtration is the most commonly used method to fractionate trace metal species, but often only "dissolved" and "particulate" fraction. The purpose of the present study is to determine colloidal and suspended particulate concentrations of Fe, Zn, Cu, Ni, and Mn in sea water. Suspended particulate matter were separated in three different size groups namely (>2.7 microm, <2.7->0.45 microm and <0.45->0.22 microm) by suction filtration using cellulose acetate and nitrate filter membranes. Thereafter to concentrate the solution with colloidal particle <0.22 microm-1.1 nm (0.5 k Nominal Molecular Weight cut-off Limit {NMWL}), the solution obtained from filtration through <0.22 microm, is sequentially passed through the ultra-filtration membranes having pore diameters of 14 nm (300 k NMWL), 3.1 nm (50 k NMWL), 2.2 nm (30 k NMWL), 1.6 nm (10 k NMWL) and 1.1 nm (0.5 k NMWL) by using Stirred Ultra-filtration Cells, operating in concentration mode. The concentration of Fe, Zn, Cu, Ni, and Mn were measured in suspended and dissolved fraction by ion chromatography, ICP-AES and Atomic Absorption Spectrometer. The salinity of the solution in various dissolved fractions of sequential filtration varies between 30.89-34.22 parts per thousand. The maximum concentrations of colloidal Zn, Cu, Ni and Mn in dissolved fraction were in <2.2->1.6 nm fraction. In case of Fe, colloidal fractions <2.2->1.6 nm and <1.6-<1.1 nm shows higher concentration. The concentration of Zn, Cu, Ni and Mn increase with decrease in size in suspended particulate matter, while the reverse is observed in case of Fe. This size separation data that specifies the partitioning of metals between dissolved and suspended solid phases is necessary for developing physically based models of metal transport in aquatic system. 相似文献
103.
Kumar P. Senthil Suganya S. Srinivas S. Priyadharshini S. Karthika M. Karishma Sri R. Swetha V. Naushad Mu. Lichtfouse Eric 《Environmental Chemistry Letters》2019,17(4):1707-1726
Environmental Chemistry Letters - Delivering the right amount of fluoride to drinking water protects the teeth from decay and reduces the risk of cavities. Nonetheless, fluorosis has been... 相似文献
104.
Bhushan Bharat Singh Brij Pal Saini Kamna Kumari Mamta Tomar Sudhir Kumar Mishra Vijendra 《Environmental Chemistry Letters》2019,17(4):1801-1820
Environmental Chemistry Letters - Microbial cells react with intestinal surfaces and produce enzymes and metabolites that influence human health, host metabolism and immunity. Gut... 相似文献
105.
Luo Dan Wang Luyao Nan Hongyan Cao Yijun Wang Hui Kumar Thakur Vijay Wang Chongqing 《Environmental Chemistry Letters》2023,21(1):497-524
Environmental Chemistry Letters - Phosphorus is essential element for agricultural production, yet phosphorus ore resources are non-renewable and become depleted. Moreover, phosphate release from... 相似文献
106.
Ansari Faiz Ahmad Guldhe Abhishek Gupta Sanjay Kumar Rawat Ismail Bux Faizal 《Environmental science and pollution research international》2021,28(32):43234-43257
Environmental Science and Pollution Research - The aquaculture industry is an efficient edible protein producer and grows faster than any other food sector. Therefore, it requires enormous amounts... 相似文献
107.
Fang Jianchun Gozgor Giray Mahalik Mantu Kumar Padhan Hemachandra Xu Ruihui 《Environmental science and pollution research international》2021,28(26):33771-33780
Environmental Science and Pollution Research - This paper investigates the role of economic complexity on energy demand using the panel dataset of 25 Organization for Economic Co-operation and... 相似文献
108.
Kumar Ritesh Mishra Indrani Kumar Gulshan 《Journal of Polymers and the Environment》2021,29(11):3770-3778
Journal of Polymers and the Environment - Biocompatible chitosan/PVP blends of different weight ratios were prepared by the solution casting method. The blends were characterized for morphology,... 相似文献
109.
Singh Lok Pratap Dhaka Rahul Kumar Ali Dilshad Tyagi Inderjeet Sharma Usha Banavath Srinivasrao Naik 《Environmental science and pollution research international》2021,28(26):34087-34107
Environmental Science and Pollution Research - Nano-titania (n-TiO2), due to its unique photocatalytic and hydrophobic properties, can be used to prepare self-cleaning cement-based smart building... 相似文献
110.