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1.
The objective of this work was to isolate cellulose nanocrystal (CNC) from oil palm fronds (Elaeis guineensis) and its subsequent characterization. Isolation involves sodium hydroxide/anthraquinone pulping with mechanical refining followed by total chlorine free bleaching (includes oxygen delignification, hydrogen peroxide oxidation and peracetic acid treatment) before acid hydrolysis. Bleaching significantly decreased kappa number and increased α-cellulose percentage of fibers as confirmed by Technical Association of the Pulp and Paper Industry standards. Transmission electron microscopy (TEM), X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetric analysis revealed that acid hydrolysis along with bleaching improved crystallinity index and thermal stability of the extracted nanocrystals. It was observed that CNC maintained its cellulose 1 polymorph despite hydrolysis treatment. Mean diameter as observed by TEM and average fiber aspect ratio of obtained CNC was 7.44 ± 0.17 nm and 16.53 ± 3.52, respectively making it suitable as a reinforcing material for nanocomposite.  相似文献   
2.
The present study was conducted to isolate and explore bacterial strains with a potential to sequester lead (Pb) and tolerate other heavy metals from industrial effluents and sediments. Out of the six bacterial strains isolated from seleniferous sites of Punjab, three isolates (RS-1, RS-2, and RS-3) were screened out for further growth-associated lead sequestration and molecular characterization on the basis of their tolerance toward lead and other heavy metals. Biomass and cell-free supernatant were analyzed for lead contents using ICP-MS after growth-associated lead sequestration studies in tryptone soya broth (pH?=?7.2?±?0.2) under aerobic conditions at 37 °C temperature. Almost 82 % and 70 % divalent lead was sequestered in cell pellets of RS-1 and RS-3, respectively while only 45 % of lead was found in cell pellet of RS-2 in the first 24 h. However, significant biosequestration of lead was observed in RS-2 after 48 h of incubation with concomitant increase in biomass. Simultaneously, morphological, biochemical, and physiological characterization of selected strains was carried out. 16S rRNA gene sequence of these isolates revealed their phylogenetic relationship with class Bacillaceae, a low G + C firmicutes showing 98 % homology with Bacillus sp.  相似文献   
3.
Environmental Science and Pollution Research - The 2019 outbreak of corona virus disease began from Wuhan (China), transforming into a leading pandemic, posing an immense threat to the global...  相似文献   
4.
Environmental Science and Pollution Research - Meningitis is an inflammation of the protective membranes called meninges and fluid adjacent the brain and spinal cord. The inflammatory progression...  相似文献   
5.
Environmental Science and Pollution Research - Nutrient source and transport study in tropical creeks adjacent to megacities are sparse on a regional and global scale. High-frequency chemical data...  相似文献   
6.
The global demand of bioplastics has lead to an exponential increase in their production commercially. Hence, biodegradable nature needs to be evaluated in various ecosystems viz. air, water, soil and other environmental conditions to avoid the polymeric waste accumulation in the nature. In this paper, we investigated the progressive response of two indigenously developed bacterial consortia, i.e., consortium-I (C-I: Pseudomonas sp. strain Rb10, Pseudomonas sp. strain Rb11 and Bacillus sp. strain Rb18), and consortium-II (C-II: Lysinibacillus sp. strain Rb1, Pseudomonas sp. strain Rb13 and Pseudomonas sp. strain Rb19), against biodegradation behavior of polyhydroxybutyrate (PHB) film composites, under natural soil ecosystem (in net house). The biodegraded films recovered after 6 and 9 months of incubation were analyzed through Fourier transform infrared spectroscopy and scanning electron microscopy to determine the variations in chemical and morphological parameters (before and after incubation). Noticeable changes in the bond intensity, surface morphology and conductivity were found when PHB composites were treated with C-II. These changes were drastic in case of blends in comparison to copolymer. The potential isolates not only survived, but, also, there was a significant increase in bacterial diversity during whole period of incubation. To the best of our knowledge, it is the first report which described the biodegradation potential of Lysinibacillus sp. as a part of C-II with Pseudomonas sp. against PHB film composites.  相似文献   
7.
Environment, Development and Sustainability - Our society faces mounting pressure regarding the necessity of green consumption as issues related to the environment will likely become a severe...  相似文献   
8.
Environmental Science and Pollution Research - The metabolic disorders are the edge points for the initiation of various diseases. These disorders comprised of several diseases including diabetes,...  相似文献   
9.
The flow of sediment particles in rivers is a big challenge to develop hydropower plants across the sediment-laden rivers. Hard particles such as quartz and feldspar are available in high amount in the Asian mountain range. The abrasive action of these particles causes the hydro turbines to suffer from erosion in particular at high- and medium-head hydroelectric power plants. This has become a serious economic issue due to maintenance costs and production losses. The treatment without prevention is simply unsustainable. Facilities for sediment exclusion, typically sand traps as well as turbine design, and materials have been improved considerably. In the present paper, studies have been discussed extensively undertaken by several investigators in this field. Based on literature survey several aspects related to reducing the sediment load on turbines, useful ways to improve the turbine surface performance and various erosion models to characterize the effect of erosion on the performance of turbines have been discussed. To calibrate and validate the developed erosion models, more measurements from both physical model tests in laboratories and continuous monitoring of sediment parameters and their impact on the operational hydro turbines are required. As well as the state-of-art in the modeling and simulation using computational fluid dynamics (CFD) has made it possible to optimize the hydraulic design of hydro turbines in order to minimize the erosion level without much sacrifice in the efficiency. To mitigate the hydro-abrasive erosion effects on the performance of turbines, significant improvements have been achieved so far and development is ongoing.  相似文献   
10.
Flubendiamide, a comparatively new insecticide, is used against lepidopteran insect pests and presumed safe for non-target Drosophila melanogaster (D. melanogaster). In this study, treatment concentrations (0.5, 1, 2 5, 10, and 20 μg/ml) of flubendiamide, lower than agricultural concentrations (rice 50μg/ml or cotton 100 μg/ml), were able to inhibit acetylcholinesterase activity in third instar larvae of D. melanogaster indicating a neurotoxic potential. In addition, larvae exposed to flubendiamide also manifested increased amounts of stress protein hsp70. The larvae expressing such stress response when allowed to emerge as adults displayed severe eye structure deformities found by scanning electron microscopy. These findings indicate a toxic potential for flubendiamide in D. melanogaster.  相似文献   
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