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201.
202.
LDPE has been mixed with LDPE-g-mA (LDPE grafted with (0.5%) maleic anhydride) in 1:1 ratio containing a polar group in the LDPE backbone. Blown film samples
containing various percentages of Potato Starch 0, 2.5, 5.0, 7.5, 10.0, 12.5 and 15% and LDPE grafted with maleic anhydride/LDPE
(1:1), have been prepared using extrusion film blowing under temperature profile ranging from 120 to 160 °C. Characteristics
of prepared packaging films up to 15% Potato Starch were analysed for their mechanical properties (Tensile strength, Elongation
at break, Bursting strength and Tear strength), water absorption properties and morphology. The compatibility of the system
with the introduction of 50% LDPE grafted with maleic anhydride with various ratios of starch, have been verified with the
help of resulting datasets. The resulting datasets were placed in theoretical models of Willet modifies Kerner’s equation and Nicolais and Narkis models. Procedure adopted above could make thermally stable, highly flexible, crystalline resultant material, which can be adopted
as an alternative of LDPE material especially for packaging applications. 相似文献
203.
Amrita Gupta Bistra Dilkina Dana J. Morin Angela K. Fuller J. Andrew Royle Christopher Sutherland Carla P. Gomes 《Conservation biology》2019,33(5):1023-1034
Ecological distance-based spatial capture–recapture models (SCR) are a promising approach for simultaneously estimating animal density and connectivity, both of which affect spatial population processes and ultimately species persistence. We explored how SCR models can be integrated into reserve-design frameworks that explicitly acknowledge both the spatial distribution of individuals and their space use resulting from landscape structure. We formulated the design of wildlife reserves as a budget-constrained optimization problem and conducted a simulation to explore 3 different SCR-informed optimization objectives that prioritized different conservation goals by maximizing the number of protected individuals, reserve connectivity, and density-weighted connectivity. We also studied the effect on our 3 objectives of enforcing that the space-use requirements of individuals be met by the reserve for individuals to be considered conserved (referred to as home-range constraints). Maximizing local population density resulted in fragmented reserves that would likely not aid long-term population persistence, and maximizing the connectivity objective yielded reserves that protected the fewest individuals. However, maximizing density-weighted connectivity or preemptively imposing home-range constraints on reserve design yielded reserves of largely spatially compact sets of parcels covering high-density areas in the landscape with high functional connectivity between them. Our results quantify the extent to which reserve design is constrained by individual home-range requirements and highlight that accounting for individual space use in the objective and constraints can help in the design of reserves that balance abundance and connectivity in a biologically relevant manner. 相似文献
204.
Gupta Ankit Kumar Bafna Minal Srivastava Subodh Khanna Rajendra Kumar Vijay Yogesh Kumar 《Environmental science and pollution research international》2021,28(4):3880-3887
Environmental Science and Pollution Research - In this paper, we present the studies on electromagnetic interference (EMI) shielding effectiveness (SE) of K2CrO4-PMMA composites developed by two... 相似文献
205.
Agrawal Yash Gupta Trilok Sharma Ravi K. 《Journal of Material Cycles and Waste Management》2022,24(1):268-286
Journal of Material Cycles and Waste Management - The present study focuses on utilizing stockpiled dolomite quarry waste for sustainable and cleaner production of concrete. Natural river sand is... 相似文献
206.
Bakshi Payal Pappu Asokan Gupta Manoj Kumar 《Journal of Material Cycles and Waste Management》2022,24(1):49-62
Journal of Material Cycles and Waste Management - This study provides an overview of calcium rich industrial wastes usage in construction materials, their properties and different applications... 相似文献
207.
Gupta Himanshu Kumar Harish Gehlaut Avneesh Kumar Singh Satish Kumar Gaur Ankur Sachan Sadhana Park Jin-Won 《Journal of Material Cycles and Waste Management》2022,24(2):569-581
Journal of Material Cycles and Waste Management - A great deal of focus has been given to finding a bio-composite film to substitute petroleum-based synthetic plastic in recent years. Many animals... 相似文献
208.
Bhargava Shrey Kumar Singh Thakur Gurjeet Mannan Ashi Singh Shareen Singh Manjinder Gupta Saurabh 《Environmental science and pollution research international》2022,29(40):60542-60557
Environmental Science and Pollution Research - When diabetes neuropathy occurs, the oxidative stress caused by chronic hyperglycemia may result in chronic neuronal damage. To mitigate the effects... 相似文献
209.
Datta JK Sadhu S Gupta S Saha R Mondal NK Mukhopadhyay B 《Journal of environmental biology / Academy of Environmental Biology, India》2006,27(3):609-612
Cities and towns of the world are now facing enormous rise of noise pollution problem due to very high population rise, transport congestion and associated commercial and industrial activities. Burdwan, a district headquarter (100 km away from Kolkata) is one such town where noise pollution is very frequent. In order to assess noise level, noise data were collected from various places of the town by sound level meter with a duration of 30 minutes/location during specified time like 6.00 am, 10.00 am, 1.00 pm, 4.00 pm and 6.00 pm. Most of the monitoring places either belongs to silence category or commercial category areas. From the tabulated data, it was found that sound level lies within the range of 64-85 dB or above in different time at different places. The locations that belong to the silence zone have the noise level up to 90 dB. Statistically noise level in all these zones differ significantly at their peak hours. Noise pollution adversely affects our environment as well as human beings. Sound causes both pathological and psychological disorders in human beings. Implementation of rules and regulations under section 20, 21J, 41, 68(I), 70, 90, 111A of Environment Protection Act, 1986 and of course various technological methods and public awareness are very essential to check noise pollution in Burdwan town. 相似文献
210.
Coontail (Ceratophyllum demersum L.) plants when exposed to various concentrations of Pb (1-100microM) for 1-7days, exhibited both phytotoxic and tolerance responses. The specific responses were function of concentration and duration. Plants accumulated 1748mugPbg(-1) dw after 7d which reflected its metal accumulation ability, however most of the metal (1222microgg(-1) dw, 70%) was accumulated after 1d exposure only. The toxic effect and oxidative stress caused by Pb were evident by the reduction in biomass and photosynthetic pigments and increase in malondialddehyde (MDA) content and electrical conductivity with increase in metal concentration and exposure duration. Morphological symptoms of senescence phenomena such as chlorosis and fragmentation of leaves were observed after 7d. The metal tolerance and detoxification strategy adopted by the plant was investigated with reference to antioxidant system and synthesis of phytochelatins. Protein and antioxidant enzymes viz., superoxide dismutase (SOD, EC 1.15.1.1), guaiacol peroxidase (GPX, EC 1.11.1.7) ascorbate peroxidase (APX, EC 1.11.1.11), catalase (CAT, EC 1.11.1.6) and glutathione reductase (GR, EC 1.6.4.2) showed induction at lower concentration and duration followed by decline. All enzymes except GPX showed maximum activity after 1d. An increase in cysteine, non-protein thiols (NP-SH) and glutathione (GSH) content was observed at moderate exposure conditions followed by decline. Phytochelatins (PC(2) and PC(3)) were synthesized to significant levels at 10 and 50microM Pb with concomitant decrease in GSH levels. Thus production of PCs seems important for the detoxification of metal, however it may lead to depletion of GSH and consequently oxidative stress. Results suggest that plants responded positively to moderate Pb concentrations and accumulated high amount of metal. Due to metal accumulation coupled with detoxification potential, the plant appears to have potential for its use as phytoremediator species in aquatic environments having moderate pollution of Pb. 相似文献