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1. Inferential Self-Optimizing Control of a Reactor–Separator–Recycle Process

Author:
Kumar, Vivek,   et al.   ; Kaistha, Nitin;     Show all 2 Author
Source:
Industrial & engineering chemistry process design and development 2019 v.58 no.33 pp. 15209-15221
ISSN:
1520-5045
Subject:
distillation; economic impact; financial economics; process design; reaction chemistry; temperature
Abstract:
... Self-optimizing control of a reactor–separator–recycle process with A + B → C reaction chemistry is evaluated for mode I (minimize recycle rate or column boilup at given production) and mode II (maximize throughput with maximum recycle or boilup as the bottleneck). In both modes, one unconstrained degree of freedom (DOF) remains after accounting for the active constraints. Through an analysis of t ...
DOI:
10.1021/acs.iecr.9b00172

2. Numerical and experimental investigations on heat transfer and pressure drop characteristics of Al2O3-TiO2 hybrid nanofluid in minichannel heat sink with different mixture ratio

Author:
Kumar, Vivek,   et al.   ; Sarkar, Jahar;     Show all 2 Author
Source:
Powder technology 2019 v.345 pp. 717-727
ISSN:
0032-5910
Subject:
Reynolds number; aluminum oxide; convection; friction; heat transfer coefficient; mixing; models; nanofluids; nanoparticles; powders; synergism; temperature
Abstract:
... Heat transfer and pressure drop characteristics of minichannel heat sink are analysed experimentally and numerically (two-phase mixture model) by using hybrid nanofluids. Minichannel heat sink consists of 9 parallel rectangular shaped minichannels having depth of 3 mm and width of 1 mm. The Al2O3–TiO2 hybrid nanofluid with nanoparticles volume concentration of 0.1% with different nanoparticle mixt ...
DOI:
10.1016/j.powtec.2019.01.061

3. Real-Time Optimization of a Reactor–Separator–Recycle Process II: Dynamic Evaluation

Author:
Kumar, Vivek,   et al.   ; Kaistha, Nitin;     Show all 2 Author
Source:
Industrial & engineering chemistry process design and development 2019 v.58 no.5 pp. 1966-1977
ISSN:
1520-5045
Subject:
economic performance; equipment; financial economics; inventories; process design
Abstract:
... The dynamic performance of a fully automatic real-time optimization (RTO) scheme is evaluated for a reactor–separator–recycle process in mode I (minimize column boilup at given throughput) and mode II (maximize production) operation. In both modes, the reactor composition set point is the optimized unconstrained degree of freedom. The RTO requires a simple override control scheme to reconfigure th ...
DOI:
10.1021/acs.iecr.8b04274

4. Physical and chemical characteristics of different cultivars of Indian gooseberry (Emblica officinalis)

Author:
Kumar, Vivek,   et al.   ; Tewari, Rishika; Sharma, H. K.;     Show all 3 Authors
Source:
Journal of food science and technology 2019 v.56 no.3 pp. 1641-1648
ISSN:
0022-1155
Subject:
Ayurvedic medicine; Phyllanthus emblica; ascorbic acid; ash content; chemical constituents of plants; color; cultivars; fruit composition; fruits; geometry; hardness; medicinal properties; minerals; physicochemical properties; polyphenols; proximate composition; rolling; surface area; value-added products; water content; India
Abstract:
... Indian gooseberry (Emblica officinalis) commonly known as amla is one of the important fruit of Ayurveda. Nutritional and medicinal properties of amla make it a well known fruit. It is an excellent source of vitamin C, phytochemicals and minerals. Several cultivars of amla are grown throughout different parts of India. Physical characteristics are imperative for designing the equipments for proces ...
DOI:
10.1007/s13197-019-03595-y

5. Real Time Optimization of a Reactor–Separator–Recycle Process I: Steady State Modeling

Author:
Kumar, Vivek,   et al.   ; Kaistha, Nitin;     Show all 2 Author
Source:
Industrial & engineering chemistry process design and development 2018 v.57 no.37 pp. 12429-12443
ISSN:
1520-5045
Subject:
financial economics; kinetics; models; process design; temperature profiles
Abstract:
... Steady state real time optimization (RTO) of a reactor–separator–recycle process is studied. The reaction A + B → C occurs in the reactor with the separator recycling unreacted A and B and recovering nearly pure C bottoms product. Two operating scenarios, Mode I (fixed throughput) and Mode II (maximum throughput), are considered. In Mode I, the column boil-up is minimized using available degrees-o ...
DOI:
10.1021/acs.iecr.8b00839

6. Sustainable utilization of paper mill solid wastes via synthesis of nano silica for production of belite based clinker

Author:
Kumar, Vivek,   et al.   ; Vashistha, Prabhat; Singh, S.K.; Dutt, Dharm;     Show all 4 Authors
Source:
Journal of cleaner production 2019 v.224 pp. 557-565
ISSN:
0959-6526
Subject:
acid deposition; alkali treatment; aluminum oxide; construction materials; crystal structure; fly ash; moieties; nanomaterials; pulp and paper mills; raw materials; silica; sludge; solid wastes; stabilizers; surface area; temperature
Abstract:
... The industrial solid waste generation and its stockpile disposal have major environmental consequences. These consequences could be minimized through the solid waste application as a raw material in other industries. The current study focusses on the utilization of lime sludge with boiler ash synthesized nanosilica for production of belite based clinker at relatively lower temperature. Lime sludge ...
DOI:
10.1016/j.jclepro.2019.03.207

7. Treatment of pulp and paper mill effluent by a novel bacterium Bacillus sp. IITRDVM-5 through a sequential batch process

Author:
Kumar, Vivek,   et al.   ; Sonkar, Madan; Kumar, Madan; Dutt, Dharm;     Show all 4 Authors
Source:
Biocatalysis and agricultural biotechnology 2019 v.20 pp. 101232
ISSN:
1878-8181
Subject:
Bacillus (bacteria); Fourier transform infrared spectroscopy; Trigonella foenum-graecum; Vigna radiata; bacteria; batch systems; biochemical oxygen demand; chemical oxygen demand; color; decolorization; gas chromatography-mass spectrometry; lignin; moieties; nitrogen; paper; phenols; phosphorus; pulp; pulp and paper mill effluents; seeds; toxicity; ultraviolet-visible spectroscopy
Abstract:
... The various types of biorefractory organic pollutants present in pulp and paper mill effluent is obnoxious to the environment and severely affects the biotic and abiotic components. The present study investigates the isolation and characterization of a novel strain isolated from pulp and paper mill effluent. Among the isolates, the strain Bacillus sp. IITRDVM-5 showed maximum degradation and decol ...
DOI:
10.1016/j.bcab.2019.101232

8. Synergetic effect of vancomycin loaded silver nanoparticles for enhanced antibacterial activity

Author:
Kumar, Vivek,   et al.   ; Kaur, Amritpal; Preet, Simran; Kumar, Rajeev; Kumar, Rajesh;     Show all 5 Authors
Source:
Colloids and surfaces 2019 v.176 pp. 62-69
ISSN:
0927-7765
Subject:
Escherichia coli; Fourier transform infrared spectroscopy; Staphylococcus aureus; X-ray diffraction; agar; antibacterial properties; bacteria; chemical reduction; citrates; colloids; drugs; glycopeptides; hydrogen bonding; ionic surfactants; nanoparticles; nanosilver; oxygen; particle size; particle size distribution; reducing agents; silver nitrate; synergism; transmission electron microscopy; ultraviolet-visible spectroscopy; vancomycin
Abstract:
... In recent years, there is significant growth in the bacterial resistance to various classic antibiotics. This has opened and enhanced the field of metal nanoparticles and antibiotic-metal nanoparticle complex. This research was designed to load a glycopeptide antibiotic named vancomycin on citrate-capped silver nanoparticles to enhance its antibacterial activity against both Gram-positive (Staphyl ...
DOI:
10.1016/j.colsurfb.2018.12.043

9. An assessment of trace element contamination in groundwater aquifers of Saharanpur, Western Uttar Pradesh, India

Author:
Kumar, Vivek,   et al.   ; Kumar, Amrish; Bharti,; Malyan, Sandeep K.; Kumar, Smita S.; Dutt, Dharm;     Show all 6 Authors
Source:
Biocatalysis and agricultural biotechnology 2019 v.20 pp. 101213
ISSN:
1878-8181
Subject:
World Health Organization; aquifers; arsenic; cadmium; chromium; drinking water; groundwater; groundwater contamination; growth and development; human health; iron; lead; mercury; pumps; risk; water quality; zinc; India
Abstract:
... Groundwater is a vital natural resource needed for the growth and development of life on the Earth. The aim of the present study was to estimate trace elements concentration in groundwater and their effect on human health in Saharanpur district, Uttar Pradesh, India. Groundwater samples were collected from the government hand pumps and analyzed for eight trace elements using ICP-MS. In all the sam ...
DOI:
10.1016/j.bcab.2019.101213

10. Ferrous sulfate as an in-situ anodic coagulant for enhanced bioelectricity generation and COD removal from landfill leachate

Author:
Kumar, Vivek,   et al.   ; Kumar, Smita S.; Kumar, Ritesh; Malyan, Sandeep K.; Bishnoi, Narsi R.;     Show all 5 Authors
Source:
Energy 2019 v.176 pp. 570-581
ISSN:
0360-5442
Subject:
bioelectricity; catalysts; catalytic activity; chemical oxygen demand; coagulants; coagulation; electrodes; experimental design; ferrous sulfate; graphene; landfill leachates; microbial fuel cells; microorganisms; models; pH; power generation; response surface methodology
Abstract:
... Landfill Leachate is a heavily contaminated wastewater. MFCs (Microbial Fuel cells) are unique bioreactors, which utilize the catalytic activity of microbes for converting the chemical energy stored in organic-rich streams for bioelectricity production. MFCs represent an auspicious technology to treat landfill leachate and generate bioelectricity. Here, we evaluated the addition of ferrous sulfate ...
DOI:
10.1016/j.energy.2019.04.014

11. Shrinkage and rehydration characteristics of vacuum assisted microwave dried green bell pepper

Author:
Kumar, Vivek,   et al.   ; Devi, Moirangthem Kalpana; Panda, Brajesh Kumar; Shrivastava, Shanker Lal;     Show all 4 Authors
Source:
Journal of food process engineering 2019 v.42 no.4 pp. e13030
ISSN:
0145-8876
Subject:
air drying; bulk density; casseroles; color; diffusivity; dried vegetables; packaging; pizza; porosity; recipes; rehydration; sensory properties; shrinkage; soups; stews; sweet peppers; water content
Abstract:
... Green bell pepper was dried under vacuum assisted microwave (VAM) drying conditions. The effect of microwave power (100, 200, 300 W) and vacuum pressure (200, 400, 600 mmHg) were observed on shrinkage and rehydration characteristics of the sample. Shrinkage was modeled as a linear function of volume change of material and its moisture content. A model was proposed where apparent density could be e ...
DOI:
10.1111/jfpe.13030

12. Divergent Supramolecular Gelation of Backbone Modified Short Hybrid δ-Peptides

Author:
Kumar, Vivek,   et al.   ; Reja, Rahi M.; Patel, Rajat; Jha, Anjali; Gopi, Hosahudya N.;     Show all 5 Authors
Source:
Biomacromolecules 2019 v.20 no.3 pp. 1254-1262
ISSN:
1526-4602
Subject:
amino acids; biocompatible materials; cell culture; culture media; dipeptides; gelation; hydrogels; oil spills; phosphates; proteolysis; solvents
Abstract:
... The ordered supramolecular assemblies of short peptides have been recently gaining momentum due to their widespread applications in biology and materials sciences. In contrast to the α-peptides, limited success has been achieved from the backbone modified peptides. The proteolytic stability and conformational flexibility of the backbone modified peptides composed of β-, γ-, and δ-amino acids can b ...
DOI:
10.1021/acs.biomac.8b01684

13. Utility of Luffa cylindrica and Litchi chinensis peel, an agricultural waste biomass in cellulase production by Trichoderma reesei under solid state cultivation

Author:
Kumar, Vivek,   et al.   ; Verma, Nitin; Bansal, Mukesh C.;     Show all 3 Authors
Source:
Biocatalysis and agricultural biotechnology 2018 v.16 pp. 483-492
ISSN:
1878-8181
Subject:
Litchi chinensis; Luffa aegyptiaca; Trichoderma reesei; agricultural wastes; bioenergy; biomass; byproducts; carbon; cost effectiveness; endo-1,4-beta-glucanase; fruit peels; fruit products; hydrolysates; solid state culture; solid wastes; starch; vegetables; waste management; whey
Abstract:
... Agricultural waste biomass represent the most abundant renewable carbon source on earth for the production of bioenergy, chemicals, enzymes and other valuable products etc. The large quantities of byproducts generated during the processing of plant food involve an economic and environmental problem due to their high volumes and disposal costs. Vegetable and fruit peels are normally thrown away as ...
DOI:
10.1016/j.bcab.2018.09.021

14. An overview of carcinogenic pollutants in groundwater of India

Author:
Kumar, Vivek,   et al.   ; Malyan, Sandeep K.; Singh, Rajesh; Rawat, Meenakshi; Kumar, Mohit; Pugazhendhi, Arivalagan; Kumar, Amrish; Kumar, Smita S.;     Show all 8 Authors
Source:
Biocatalysis and agricultural biotechnology 2019
ISSN:
1878-8181
Subject:
carcinogenicity; carcinogens; cost effectiveness; drinking; ecosystems; freshwater; groundwater; human health; industrialization; irrigation; neoplasms; pesticides; pollutants; pollution control; risk; sanitation; wastes; water pollution; water requirement; water resources; India
Abstract:
... Groundwater is the major source of freshwater for irrigation, drinking, and sanitation in India. 50% of urban water requirement and 85% of rural domestic water requirements are fulfilled by groundwater. Industrialization, unmanaged dumping of waste, extensive application of pesticides and other geological metamorphic activities have led to the contamination of freshwater resources. Consumption of ...
DOI:
10.1016/j.bcab.2019.101288

15. Geochemical and sedimentological characteristics of surface sediments from Ashtamudi Estuary, Southern India: implications for provenance and modern sedimentary dynamics

Author:
Kumar, Vivek V.,   et al.   ; Mishra, Praveen K.; Parth, Shah; Ankit, Yadav; Kumar, Sunil; Ambili, V.; Singh, Shweta; Anoop, Ambili;     Show all 8 Authors
Source:
Environmental earth sciences 2019 v.78 no.14 pp. 395
ISSN:
1866-6280
Subject:
aluminum; anthropogenic activities; basins; calcium; chromium; cobalt; copper; estuaries; hydrodynamics; iron; nickel; particle size distribution; provenance; sand; silicon; silt; strontium; titanium; zinc; India
Abstract:
... Geochemical and end-member mixing analyses (EMMA) of the grain-size distribution were conducted on recent surface sediments from Ashtamudi Estuary, Southern India to investigate the hydrodynamic factors that influence the depositional processes in the region. The complex interplay between the natural (fluvial and marine) and anthropogenic influences on the Ashtamudi Estuary have been delineated ba ...
DOI:
10.1007/s12665-019-8376-z

16. Optimization of vacuum-assisted microwave drying parameters of green bell pepper using response surface methodology

Author:
Kumar, Vivek,   et al.   ; Shrivastava, Shanker Lal;     Show all 2 Author
Source:
Journal of food measurement & characterization 2017 v.11 no.4 pp. 1761-1772
ISSN:
2193-4126
Subject:
color; hardness; microwave drying; models; prediction; regression analysis; rehydration; response surface methodology; specific energy; sweet peppers
Abstract:
... Green bell pepper was dried under vacuum-assisted microwave drying condition and the process was optimized using response surface methodology. The effect of microwave power (100–300 W) and vacuum level (200–600 mm Hg) were observed on the responses, viz. green color ratio, rehydration ratio, hardness, apparent density ratio, drying time and specific energy consumption. A central composite face-cen ...
DOI:
10.1007/s11694-017-9557-7

17. Process optimization for extraction of bioactive compounds from taro (Colocasia esculenta), using RSM and ANFIS modeling

Author:
Kumar, Vivek,   et al.   ; Sharma, H. K.;     Show all 2 Author
Source:
Journal of food measurement & characterization 2017 v.11 no.2 pp. 704-718
ISSN:
2193-4126
Subject:
2,2-diphenyl-1-picrylhydrazyl; Colocasia esculenta; antioxidant activity; antioxidants; bioactive compounds; butylated hydroxytoluene; caffeic acid; catechin; chlorogenic acid; data collection; epicatechin; flavonols; flour; gallic acid; liquid chromatography; models; prediction; response surface methodology; solvents; taro; temperature
Abstract:
... Response surface methodology (RSM) and adaptive neuro fuzzy inference system (ANFIS) modeling was applied for optimization of process parameters for extraction of bioactive compounds from taro flour. A Face-centered central composite design (FCCD) was adopted to study the effects of process parameters on Total phenolic content (TPC), Total flavonoid content (TFC) and their antioxidant activity in ...
DOI:
10.1007/s11694-016-9440-y

18. Sustainable utilization of deinking paper mill sludge for the manufacture of building bricks

Author:
Kumar, Vivek,   et al.   ; Singh, S.K.; Kulkarni, Shilpa; Vashistha, Prabhat;     Show all 4 Authors
Source:
Journal of cleaner production 2018 v.204 pp. 321-333
ISSN:
0959-6526
Subject:
X-ray diffraction; alluvial soils; bricks; compression strength; deinking; energy efficiency; manufacturing; porosity; pulp and paper sludge; shrinkage; sludge; temperature; thermal conductivity; waste management; water uptake
Abstract:
... Building bricks were produced by utilizing deinking paper mill sludge (DPMS) and alluvial soil by varying percentage of sludge at different firing temperatures. Different mix proportions were prepared with 0%, 5%, 10%, 15%, 20%, 25% and 30% of DPMS incorporation in alluvial soil by weight. Three firing temperatures of 900 °C, 950 °C and 1000 °C were investigated to simulate the typical condition o ...
DOI:
10.1016/j.jclepro.2018.09.028

19. Production and purification of an alkaline lipase from Bacillus sp. for enantioselective resolution of (±)-Ketoprofen butyl ester

Author:
Kumar, Vivek,   et al.   ; Saraswat, Rashmi; Bhushan, Indu; Gupta, Pankaj; Verma, Vijeshwar;     Show all 5 Authors
Source:
3 Biotech 2018 v.8 no.12 pp. 491
ISSN:
2190-572X
Subject:
Bacillus subtilis; Pseudozyma antarctica; agitation; biomass; calcium chloride; carboxylic ester hydrolases; enantioselectivity; ketoprofen; metal ions; molecular weight; olive oil; pH; peptones; pharmaceutical industry; response surface methodology; solvents; surfactants; temperature
Abstract:
... The present study was conducted to purify lipase from indigenous Bacillus subtilis strain Kakrayal_1 (BSK-L) for enantioselective resolution of racemic-ketoprofen. The production of lipase (BSK-L) was optimized using Plackett–Burman and central composite design of response surface methodology (RSM). The optimized media containing olive oil (3.5%), MnSO₄ (8 mM), CaCl₂ (5 mM), peptone (20 g/l), pH ( ...
DOI:
10.1007/s13205-018-1506-6

20. Effect of rhizobacteria on arsenic uptake by macrophyte Eichhornia crassipes (Mart.) Solms

Author:
Kumar, Vivek,   et al.   ; Kaur, Parvinder; Singh, Simranjeet; Singh, Nasib; Singh, Joginder;     Show all 5 Authors
Source:
International journal of phytoremediation 2018 v.20 no.2 pp. 114-120
ISSN:
1549-7879
Subject:
Actinomyces; Azospirillum; Azotobacter; Eichhornia crassipes; Pseudomonas; arsenic; macrophytes; phytoaccumulation; plant growth-promoting rhizobacteria; pollution; rhizosphere bacteria; streams; toxicity; wastewater; India
Abstract:
... Wastewater flowing in streams and nallahs across India carries several trace metals, including metalloid arsenic (As), which are considered serious environmental contaminants due to their toxicity, and recalcitrant nature. In this study, we determined the phytoremediation of As by Eichhornia crassipes (Mart.) Solms either alone or in association with plant growth-promoting rhizobacteria. Pseudomon ...
DOI:
10.1080/15226514.2017.1337071