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Chemical fracturing (comminution) of coal provides selective breakage, which may be used to liberate inorganic sulfur from it without resorting to excessive mechanical size reduction. The technique can be used for economic precombustion desulfurization and may have many other applications in coal utilization. 相似文献
14.
Ranjan Bhattacharyya Arti Bhatia Birendra N. Ghosh Priyabrata Santra Debashis Mandal Gopal Kumar Raman Jeet Singh Madegowda Madhu Avijit Ghosh Arup K. Mandal Ranjan Paul Ashim Datta Parbodh C. Sharma Uttam K. Mandal Pramod Jha Kokkuvayil S. Anil Manickam Lalitha Mahesh Kumar Nav R. Panwar Dibyendu Sarkar Ashok K. Patra Sumanta Kundu Michael A. Fullen Jean Poesen Bhabani Sankar Das Nagarjuna N. Reddy Suresh K. Chaudhari 《European Journal of Soil Science》2023,74(4):e13388
Current widespread and intensive soil degradation in India has been driven by unprecedented levels of population growth, large-scale industrialization, high-yield agriculture, urban sprawl and the spread of human infrastructure. The damage caused to managed and natural systems by soil degradation threatens livelihoods and local services and leads to national socio-economic disruption. Human-induced soil degradation results from land clearing and deforestation, inappropriate agricultural practices, improper management of industrial effluents and wastes, careless management of forests, surface mining, urban sprawl, and ill-planned commercial and industrial development. Of these, inappropriate agricultural practices, including excessive tillage and use of heavy machinery, over-grazing, excessive and unbalanced use of inorganic fertilizers, poor irrigation and water management techniques, pesticide overuse, inadequate crop residue and/or organic carbon inputs, and poor crop cycle planning, account for nearly 40% (121 Mha) of land degradation across India. Globally, human activities related to agriculture contribute to the transgression of four of the nine Planetary Boundaries proposed by Rockström et al. (2009): Climate Change, Biodiversity Integrity, Land-system Change, and altered Phosphorus and Nitrogen Biogeochemical Flows. This review focuses on how knowledge of soil processes in agriculture has developed in India over the past 10 years, and the potential of soil science to meet the objectives of the United Nations' Sustainable Development Goal 2: Zero Hunger (End hunger, achieve food security, improved nutrition and promote sustainable agriculture), using the context of the four most relevant Planetary Boundaries as a framework. Solutions to mitigate soil degradation and improve soil health in different regions using conservation agricultural approaches have been proposed. Thus, in this review we (1) summarize the outputs of recent innovative research in India that has explored the impacts of soil degradation on four Planetary Boundaries (Climate Change, Biodiversity Loss, Land-system Change, and altered Biogeochemical Flows of Phosphorus and Nitrogen) and vice-versa; and (2) identify the knowledge gaps that require urgent attention to inform developing soil science research agendas in India, to advise policy makers, and to support those whose livelihoods rely on the land. 相似文献
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Mahaveer Nogiya Bhupinder Singh Geeta Singh Mahesh Chand Meena Samar C. Datta 《Archives of Agronomy and Soil Science》2019,65(10):1387-1400
Iron deficiency is a serious nutritional disorder in aerobic rice, causing chlorosis, poor yields and reduced grain nutritional quality. The problem can be managed by complementing the use of Fe-efficient plant type with a suitable Fe management strategy. In the present paper, we report the effect of eight iron management practices to resolve the problem of iron (Fe) chlorosis through the use of an iron deficiency tolerant (IDTR) and iron deficiency susceptible (IDSR) rice genotype, i.e. Pusa 33 and ADT 39, respectively. Fe deficiency tolerance of these genotypes was related to the root release of PS which enabled a higher uptake of Fe in the IDTR than the IDSR under Fe deficiency. In general, IDTR performed better than the IDSR as evident from a significant increase in total iron, active iron, chlorophyll content and grain and straw yield. IDSR produced the highest grain and straw yield under slow iron release nano clay complex source. Grain Fe content of the IDTR and IDSR increased by 18.9 and 13.4%, respectively, under recommended dose of Fe. The results identified the most effective soil management strategies for the alleviating Fe deficiency chlorosis and improving Fe nutrition of both IDTR and IDSR genotypes. 相似文献
16.
Rahul Navik Faizan Shafiq Asfandyar Khan Manoj Datta Xiongyi Peng Md. Kamruzzaman Yingjie Cai 《Fibers and Polymers》2017,18(6):1115-1123
Wool fabric was treated with liquid ammonia at -40 °C for 30 and 60 s prior to the application of polypyrrole (PPy). The polymer was deposited on wool fiber using the chemical oxidation method with 0.02 and 0.05 mol/l (Py) monomer concentration and FeCl3 as a catalyst. Functional groups of wool samples were analyzed using FT-IR, and surface morphology was investigated using SEM micrographs. Properties such as water absorbency, surface resistivity, abrasion resistance, weight add-on, and air permeability of coated specimens were explored. The FT-IR outcomes revealed the liquid ammonia pre-treatment changed the amount of amide I (NH), cystic acid, cystic monoxide, and dioxide content of the fiber. SEM micrographs revealed the descaling of wool surface after pre-treatment and smooth coating of polymer. Pre-treatment of wool in liquid ammonia improved absorbency of wool fabric with respect to the treatment duration. The surface resistivity of wool fabric decreased with the increase of monomer concentration and pre-treatment duration. The results of abrasion resistance confirmed that the pre-treated fabric exhibited lower loss of polymer after 200 cycles of abrasion. The weight of the fabric was increased and air permeability decreased when the monomer concentration and liquid ammonia pre-treatment duration was increased. 相似文献
17.
Datta Apurba Kumar Haider Mohammed Ziaul Ghosh Sumon Kumar 《Tropical animal health and production》2019,51(1):55-64
Tropical Animal Health and Production - A study was conducted to analyze the dairy farming sector of Bangladesh from an economic viewpoint. Primary data was collected from smallholder dairy farms... 相似文献
18.
Yuefan Song Peng He Andre L. Rodrigues Payel Datta Ritesh Tandon John T. Bates Michael A. Bierdeman Chen Chen Jonathan Dordick Fuming Zhang Robert J. Linhardt 《Marine drugs》2021,19(12)
The COVID-19 pandemic is a major human health concern. The pathogen responsible for COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), invades its host through the interaction of its spike (S) protein with a host cell receptor, angiotensin-converting enzyme 2 (ACE2). In addition to ACE2, heparan sulfate (HS) on the surface of host cells also plays a significant role as a co-receptor. Our previous studies demonstrated that sulfated glycans, such as heparin and fucoidans, show anti-COVID-19 activities. In the current study, rhamnan sulfate (RS), a polysaccharide with a rhamnose backbone from a green seaweed, Monostroma nitidum, was evaluated for binding to the S-protein from SARS-CoV-2 and inhibition of viral infectivity in vitro. The structural characteristics of RS were investigated by determining its monosaccharide composition and performing two-dimensional nuclear magnetic resonance. RS inhibition of the interaction of heparin, a highly sulfated HS, with the SARS-CoV-2 spike protein (from wild type and different mutant variants) was studied using surface plasmon resonance (SPR). In competitive binding studies, the IC50 of RS against the S-protein receptor binding domain (RBD) binding to immobilized heparin was 1.6 ng/mL, which is much lower than the IC50 for heparin (~750 ng/mL). RS showed stronger inhibition than heparin on the S-protein RBD or pseudoviral particles binding to immobilized heparin. Finally, in an in vitro cell-based assay, RS showed strong antiviral activities against wild type SARS-CoV-2 and the delta variant. 相似文献
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Changes in carbon pools and biological activities of a sandy loam soil under medium‐term conservation agriculture and diversified cropping systems 下载免费PDF全文
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Utilization of electron beam irradiated Jatropha kernel meal in the diet of Labeo rohita (Hamilton, 1822) fingerlings 下载免费PDF全文
B.N. Sanap P. Sardar N.P. Sahu V. Phulia N. Shamna S. Dasgupta G.H. Pailan D.L. Prabu S. Datta 《Aquaculture Nutrition》2018,24(4):1304-1317
Defatted Jatropha kernel meal (DJKM) was irradiated through electron beam radiation at 25 kGy (IJKM). After irradiation, PEs and phytate were decreased by 36.67% and 55.27%, respectively, with slight reduction in total hydrolysed amino acids in IJKM. A 45‐day feeding trial was conducted to evaluate the utilization of irradiated Jatropha kernel meal (IJKM) in the diet of rohu (Labeo rohita) fingerlings. Five isonitrogenous (300 g/kg CP) and isoenergetic (15 MJ/kg GE) diets such as T0 (control, without IJKM), T5 (50 g/kg IJKM), T10 (100 g/kg IJKM), T15 (150 g/kg IJKM) and T20 (200 g/kg IJKM) were prepared and fed to fish of respective treatments. Fish fed diets containing T15 and T20 groups exhibited significantly lower (p < .05) weight gain, FCE, PER, ANPU, HSI, ISI, survival rate, nutrient and energy digestibility, than the other groups. Fish of higher IJKM fed groups (T15 and T20) also showed lower muscle moisture, protein, ash and higher muscle lipid content. The liver catalase and SOD activities significantly decreased in the higher IJKM fed groups. It is concluded that IJKM (irradiated by 25 kGy electron beam) can be incorporated up to 100 g/kg in carp feed with the replacement of 33% soybean meal and 28% ground nut oil cake without compromising growth performances of Labeo rohita. 相似文献