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1. Visible-Light-Mediated β-C(sp³)–H Amination of Glycosylimidates: En Route to Oxazoline-Fused/Spiro Nonclassical Bicyclic Sugars

Author:
Kumar, Amit,   et al.   ; Shaw, Mukta;     Show all 2 Author
Source:
Organic letters 2019 v.21 no.9 pp. 3108-3113
ISSN:
1523-7052
Subject:
amination; chemical bonding; diastereoselective synthesis; glycosylation; light; moieties; organic compounds; regioselectivity; sugars
Abstract:
... A straightforward route has been developed for the diastereoselective synthesis of nonclassical conformationally constrained oxazoline-fused and spiro bicyclic sugars bearing a quaternary center via selective β-C–H amination of appropriately positioned glycosylimidates. The desired transformation proceeds via the generation of imidate N-radicals under visible-light conditions followed regioselecti ...
DOI:
10.1021/acs.orglett.9b00763

2. Greenhouse gas measurement from Chinese freshwater bodies: A review

Author:
Kumar, Amit,   et al.   ; Yang, Tao; Sharma, M.P.;     Show all 3 Authors
Source:
Journal of cleaner production 2019 v.233 pp. 368-378
ISSN:
0959-6526
Subject:
carbon dioxide; climate change; dams (hydrology); ecoregions; freshwater; gases; greenhouse gas emissions; greenhouse gases; industry; lakes; methane; prediction; rivers; surface water; uncertainty; water power
Abstract:
... Freshwater bodies are found as significant sources of greenhouse gas to the atmosphere, but their quantitative significance is not yet clear. The rapid increase in hydropower dams and associated emissions has received much attention from hydropower industries, environmentalists, and policymakers from across the globe. The tropical/subtropical eco-regions are, particularly, considered as hotspots f ...
DOI:
10.1016/j.jclepro.2019.06.052

3. Comparative energy and techno-economic analyses of two different configurations for hydrothermal carbonization of yard waste

Author:
Kumar, Amit,   et al.   ; Akbari, Maryam; Oyedun, Adetoyese Olajire;     Show all 3 Authors
Source:
Bioresource technology reports 2019 v.7 pp. 100210
ISSN:
2589-014X
Subject:
biocoal; biomass; energy; heat; heat exchangers; hydrochars; hydrothermal carbonization; models; production costs; separators; steam; yard wastes
Abstract:
... Hydrothermal carbonization (HTC) includes conversion of wet biomass to hydrochar, a coal-like product, eliminating the need for biomass pre-drying. There has been limited focus on the techno-economic assessment of the HTC process in the literature. In this study, techno-economic models were developed to assess the economics of bio-coal production from yard waste for two different HTC plant configu ...
DOI:
10.1016/j.biteb.2019.100210

4. Novel satellite based analytical model developed to predict microalgae yields in open pond raceway systems and applied to Canadian sites

Author:
Kumar, Amit,   et al.   ; Pankratz, Stan; Oyedun, Adetoyese Olajire;     Show all 3 Authors
Source:
Algal research 2019 v.39 pp. 101431
ISSN:
2211-9264
Subject:
active ingredients; algae culture; ambient temperature; biofuels; biomass; carbon dioxide; data collection; drugs; fertilizers; functional foods; lakes; latitude; life cycle assessment; medicine; microalgae; models; nitrates; nutrients; phosphates; photobioreactors; prediction; remote sensing; satellites; solar radiation; water temperature; Alberta; Arizona; Northwest Territories; Saskatchewan
Abstract:
... Interest in microalgae cultivation continues to increase based on its potential commercial value. Algae converts CO2, nitrates, phosphates and other nutrients into a biomass that can be processed into biofuels, pharmaceuticals, nutraceuticals, food, fertilizers, and other active compounds. Solar irradiance and media temperatures are key parameters in determining microalgae cultivation yield and he ...
DOI:
10.1016/j.algal.2019.101431

5. Extracellular DNA in Monochloraminated Drinking Water and Its Influence on DNA-Based Profiling of a Microbial Community

Author:
Kumar, Amit,   et al.   ; Sakcham, Bairoliya; Cao, Bin;     Show all 3 Authors
Source:
Environmental science & technology letters 2019 v.6 no.5 pp. 306-312
ISSN:
2328-8930
Subject:
DNA; biofilm; byproducts; disinfectants; disinfection; drinking water; glass fibers; microbial communities; porosity; species diversity; water distribution
Abstract:
... The interaction between biofilms and disinfectant in drinking water distribution systems (DWDS) as well as the role of this interaction in the formation of disinfection byproducts has been extensively studied in recent years. In contrast, lysis of cells and/or release of intracellular biomolecules from inactivated/damaged cells and their fate and implications are an overlooked aspect of DWDS. In p ...
DOI:
10.1021/acs.estlett.9b00185

6. A review of the mechanical and thermal properties of graphene and its hybrid polymer nanocomposites for structural applications

Author:
Kumar, Amit,   et al.   ; Sharma, Kamal; Dixit, Amit Rai;     Show all 3 Authors
Source:
Journal of materials science 2019 v.54 no.8 pp. 5992-6026
ISSN:
0022-2461
Subject:
composite polymers; graphene; mechanical properties; microscopy; polymer nanocomposites; synergism; thermal properties; thermogravimetry
Abstract:
... In the present review, the recent progress in describing the intricacies of mechanical and thermal properties of all types of graphene- and modified graphene-based polymer nanocomposites has been comprehensively examined. The effectiveness of microscopy bouquet for the intrinsic characterization of graphene family and their composites was clearly demonstrated in this research. Furthermore, the uti ...
DOI:
10.1007/s10853-018-03244-3

7. A basic helix loop helix transcription factor, AaMYC2-Like positively regulates artemisinin biosynthesis in Artemisia annua L.

Author:
Kumar, Amit,   et al.   ; Majid, Ishfaq; Abbas, Nazia;     Show all 3 Authors
Source:
Industrial crops and products 2019 v.128 pp. 115-125
ISSN:
0926-6690
Subject:
2,4-D; Artemisia annua; DNA; abscisic acid; aldehyde dehydrogenase; amino acid sequences; artemisinin; biochemical pathways; biosynthesis; chemical bonding; cold; cytochrome P-450; dimerization; gene overexpression; genes; heat; jasmonic acid; leaves; messenger RNA; methyl jasmonate; paraquat; roots; tissues; transcription (genetics); transcription factors; transgenic plants; trichomes
Abstract:
... Artemisinin based combination therapies are still an extensively used remedy for the cure of Malaria. Although artemisinin biosynthetic pathway has been fully worked out, only few information is available on its regulatory mechanism in plants. In the present study, a new member of MYC type basic helix loop helix transcription factor was isolated from Artemisia annua and named as, AaMYC2-Like. The ...
DOI:
10.1016/j.indcrop.2018.10.083

8. Electronic and optical properties of chromophores from hexeneuronic acids

Author:
Kumar, Amit,   et al.   ; Cappellini, Giancarlo; Delogu, Francesco;     Show all 3 Authors
Source:
Cellulose 2019 v.26 no.3 pp. 1489-1501
ISSN:
0969-0239
Subject:
acids; bleaching; cellulose; chemical structure; density functional theory; hydrogen peroxide; ionization; optical properties; solvents; spectral analysis
Abstract:
... We report a systematic computational investigation on the electronic and optical properties of chromophores derived from hexeneuronic acids (HexA). In particular, we focus on five chemical structures, which account up to 90% of HexaA-derived chromophores. We performed all-electrons density functional theory (DFT) and time dependent DFT (TDDFT) calculations with a localized Gaussian basis set and t ...
DOI:
10.1007/s10570-018-2174-8

9. Long-term prediction of greenhouse gas risk to the Chinese hydropower reservoirs

Author:
Kumar, Amit,   et al.   ; Yang, Tao; Sharma, M.P.;     Show all 3 Authors
Source:
The Science of the total environment 2019 v.646 pp. 300-308
ISSN:
0048-9697
Subject:
carbon; carbon dioxide; climate; electricity generation; greenhouse gas emissions; greenhouse gases; methane; methane production; models; prediction; risk; risk assessment; sustainable development; water power; China
Abstract:
... China is undergoing an extensive hydropower development, but the magnitude of greenhouse gas (GHG) emissions risk to reservoirs is not well known. Electricity generation from hydropower is a challenging issue when it comes to sustainable development. In this study, the data on Chinese hydropower reservoirs (n = 12) were collected from the literature and is used as in input to Greenhouse Gas Risk A ...
DOI:
10.1016/j.scitotenv.2018.07.314

10. Characterization of rock-fluid and fluid-fluid interactions in presence of a family of synthesized zwitterionic surfactants for application in enhanced oil recovery

Author:
Kumar, Amit,   et al.   ; Mandal, Ajay;     Show all 2 Author
Source:
Colloids and surfaces 2018 v.549 pp. 1-12
ISSN:
0927-7757
Subject:
Fourier transform infrared spectroscopy; carbon; colloids; emulsions; micelles; nuclear magnetic resonance spectroscopy; oils; petroleum; polymers; salt tolerance; sand; surface tension; surfactants; synergism; thermodynamics; wettability; zwitterions
Abstract:
... Zwitterionic surfactants are gaining importance for their application in enhanced oil recovery (EOR) because of their favourable thermodynamic and surface properties. A family of carboxybetaine based surfactants with hydrophobic tail length of 12, 14, 16 and 18 carbons were synthesized and characterized by FTIR and 1H NMR spectroscopy. Critical micelle concentration (CMC) of the surfactants were f ...
DOI:
10.1016/j.colsurfa.2018.04.001

11. Enhanced CO2 Adsorption and Separation in Ionic-Liquid-Impregnated Mesoporous Silica MCM-41: A Molecular Simulation Study C

Author:
Kumar, Amit,   et al.   ; Kumar, Kishant;     Show all 2 Author
Source:
Journal of physical chemistry 2018 v.122 no.15 pp. 8216-8227
ISSN:
1932-7455
Subject:
adsorption; carbon dioxide; flue gas; ionic liquids; methane; models; molecular dynamics; natural gas; nitrogen; porous media; silica
Abstract:
... Separation of CO₂ from gas mixtures is of importance in CO₂ capture from flue gas and in natural gas sweetening. In this paper, we have conducted grand canonical Monte Carlo (GCMC) simulations to study the adsorption of CO₂, N₂, and CH₄ and separation of their binary mixtures in mesoporous silica MCM-41 modified by incorporation of the pyrrolidinium-based ionic liquid 1-methyl-1-butyl-pyrrolidiniu ...
DOI:
10.1021/acs.jpcc.7b11529

12. The development of a cost model for two supply chain network scenarios for decentralized pyrolysis system scenarios to produce bio-oil

Author:
Kumar, Amit,   et al.   ; Patel, Madhumita; Oyedun, Adetoyese Olajire; Doucette, John;     Show all 4 Authors
Source:
Biomass and bioenergy 2019 v.128 pp. 105287
ISSN:
0961-9534
Subject:
biofuels; biomass; forests; models; production costs; pyrolysis; supply chain
Abstract:
... Bio-oil, produced through fast pyrolysis, can act as an intermediate, which can be further upgraded to biofuels. Fast pyrolysis is done in either a centralized or a decentralized (mobile pyrolysis system [MPS]) system. In a centralized system, biomass is transported to a plant to produce bio-oil, which is upgraded in the same unit, while in a decentralized system, the mobile plant is moved to the ...
DOI:
10.1016/j.biombioe.2019.105287

13. What is the production cost of renewable diesel from woody biomass and agricultural residue based on experimentation? A comparative assessment

Author:
Kumar, Amit,   et al.   ; Patel, Madhumita; Oyedun, Adetoyese Olajire; Gupta, Rajender;     Show all 4 Authors
Source:
Fuel processing technology 2019 v.191 pp. 79-92
ISSN:
0378-3820
Subject:
Picea; agricultural wastes; biochar; biofuels; biomass; byproducts; corn stover; energy content; feedstocks; fossil fuels; gasoline; hydrogen; hydrogen production; income; market prices; models; particle size distribution; pyrolysis; temperature; transportation; wheat straw
Abstract:
... This study explores the technical and economic potential of three Canadian biomass feedstocks (spruce, corn stover and wheat straw) to replace petro-diesel through the production of renewable diesel and gasoline via fast pyrolysis and hydroprocessing. A detailed data-intensive process and cost model for a 2000 dry t d−1 plant capacity for two scenarios (hydrogen production and hydrogen purchase) w ...
DOI:
10.1016/j.fuproc.2019.03.026

14. Reactive oxygen species-mediated signaling during abiotic stress

Author:
Kumar, Amit,   et al.   ; Singh, Archana; Yadav, Sunita; Singh, Indrakant Kumar;     Show all 4 Authors
Source:
Plant gene 2019 v.18 pp. 100173
ISSN:
2352-4073
Subject:
abiotic stress; epigenetics; gene expression regulation; genes; mitogen-activated protein kinase; monitoring; organelles; oxidation; oxidative stress; oxygen; photosynthesis; post-translational modification; regulatory sequences; signal transduction; transcription (genetics); transcription factors
Abstract:
... Abiotic stress causes alterations in physiological, biochemical and metabolic equilibrium in the plant cells, leading to reduction in protein turn-over, change in post translational modification of proteins, impaired photosynthetic capability and increase in ROS production. The stress-induced ROS at higher levels can trigger oxidation of biomolecules, decomposition of membranes, inactivation of en ...
DOI:
10.1016/j.plgene.2019.100173

15. Iron-oxide nanoparticles target intracellular HSP90 to induce tumor radio-sensitization

Author:
Kumar, Amit,   et al.   ; Shetake, Neena G.; Pandey, Badri N.;     Show all 3 Authors
Source:
Biochimica et biophysica acta 2019 v.1863 no.5 pp. 857-869
ISSN:
0304-4165
Subject:
DNA damage; apoptosis; cell cycle checkpoints; cell proliferation; cyclins; drug therapy; fever; fibrosarcoma; gamma radiation; growth models; humans; iron oxides; magnetism; mice; mitosis; nanoparticles; tumor suppressor proteins
Abstract:
... Nanoparticle-based therapies have emerged as a promising approach to overcome limitations of conventional chemotherapy. Present study investigates the potential of oleic acid-functionalized iron-oxide nanoparticles (MN-OA) to enhance the radiation response of fibrosarcoma tumor and elucidates its underlying mechanism.Various cellular and molecular assays (e.g. MTT, clonogenic, cell cycle analysis, ...
DOI:
10.1016/j.bbagen.2019.02.010

16. A dimanganese(iii) porphyrin dication diradical and its transformation to a μ-hydroxo porphyrin–oxophlorin heterodimer

Author:
Kumar, Amit,   et al.   ; Sil, Debangsu; Usman, Mohammad; Rath, Sankar Prasad;     Show all 4 Authors
Source:
Chemical communications 2019 v.55 no.11 pp. 1588-1591
ISSN:
1364-548X
Subject:
chemical bonding; chemical communication; chemical reactions; ethylene; ferrimagnetic materials; free radicals; iron; manganese; models; porphyrins
Abstract:
... We investigate here the effect of electronic communication between two Mn(iii) porphyrin π-cation radicals, connected covalently through an ethylene bridge, which exhibit significant electronic communication resulting in strong antiferromagnetic coupling predominantly between two porphyrin radical spins. This, however, is in sharp contrast to its diiron(iii) analog where the porphyrin π-cation rad ...
DOI:
10.1039/c8cc09366k

17. Hyperbolic Pressure–Temperature Phase Diagram of the Zinc-Finger Protein apoKti11 Detected by NMR Spectroscopy

Author:
Kumar, Amit,   et al.   ; Klamt, Andi; Nagarathinam, Kumar; Tanabe, Mikio; Balbach, Jochen;     Show all 5 Authors
Source:
TheJournal of physical chemistry 2019 v.123 no.4 pp. 792-801
ISSN:
1520-5207
Subject:
Gibbs free energy; ambient pressure; compressibility; crystal structure; disulfide bonds; entropy; heat; models; nuclear magnetic resonance spectroscopy; physical phases; population growth; proteins; temperature; thermal expansion
Abstract:
... For a comprehensive understanding of the thermodynamic state functions describing the stability of a protein, the influence of the intensive properties of temperature and pressure has to be known. With the zinc-finger-containing Kti11, we found a suitable protein for this purpose because folding and unfolding transitions occur at an experimentally accessible temperature (280–330 °K) and pressure ( ...
DOI:
10.1021/acs.jpcb.8b11019

18. Ethnobotanical Survey of Daksum Forest Range of Anantnag District, Jammu and Kashmir, India

Author:
Kumar, Amit,   et al.   ; Fayaz, Mufida; Jain, Ashok K.; Bhat, Musadiq Hussain;     Show all 4 Authors
Source:
Journal of herbs, spices & medicinal plants 2019 v.25 no.1 pp. 55-67
ISSN:
1540-3580
Subject:
Asteraceae; Rosaceae; ethnobotany; forests; fruits; indigenous knowledge; interviews; surveys; vegetables; India
Abstract:
... An ethnobotanical study was conducted in the Daksum Forest of Anantnag district of Jammu and Kashmir State of India to document the traditional knowledge of its population, using semi-structured interviews and group conversation with 52 informants. One hundred and eight plant species, with a predominance of Asteraceae and Rosaceae, along with their detailed uses were documented. About 51 of the sp ...
DOI:
10.1080/10496475.2018.1564950

19. Microbial Community Composition and Putative Biogeochemical Functions in the Sediment and Water of Tropical Granite Quarry Lakes

Author:
Kumar, Amit,   et al.   ; Ng, Daphne H. P.; Wu, Yichao; Cao, Bin;     Show all 4 Authors
Source:
Microbial ecology 2019 v.77 no.1 pp. 1-11
ISSN:
0095-3628
Subject:
biogeochemical cycles; community structure; ecosystems; fauna; flora; granite; lakes; microbial communities; microorganisms; quarries; ribosomal DNA; sediments; trophic levels; Singapore
Abstract:
... Re-naturalized quarry lakes are important ecosystems, which support complex communities of flora and fauna. Microorganisms associated with sediment and water form the lowest trophic level in these ecosystems and drive biogeochemical cycles. A direct comparison of microbial taxa in water and sediment microbial communities is lacking, which limits our understanding of the dominant functions that are ...
DOI:
10.1007/s00248-018-1204-2

20. Analysing urban sprawl and land consumption patterns in major capital cities in the Himalayan region using geoinformatics

Author:
Kumar, Amit,   et al.   ; Diksha,;     Show all 2 Author
Source:
Applied geography 2017 v.89 pp. 112-123
ISSN:
0143-6228
Subject:
altitude; cities; entropy; geography; population density; population growth; population pressure; remote sensing; risk; socioeconomics; urban areas; urban planning; urbanization; Himalayan region
Abstract:
... In the present study, spatio-temporal urban sprawl and land consumption patterns were analysed in seven capital cities located in the Himalayan region during 1972, 1991 and 2015 using multi-temporal satellite images. The study exhibits that capital Himalayan cities experienced rapid growth (830.92%) with high population increase (333.45%) during the observation period (1972–2015). The significant ...
DOI:
10.1016/j.apgeog.2017.10.010