Analytical Modelling and Simulation Analysis of Junctionless Nanotube (JL NT) MOSFET

Raj Kumar,Raj Kumar,Arvind Kumar 한국전기전자재료학회 2022 Transactions on Electrical and Electronic Material Vol.23 No.4

In this paper, an analytical model for junctionless nanotube (JLNT) MOSFET has been developed. The analytical model for minimum central potential, threshold voltage and drain current has been developed by using variable separation method. These model expressions are further applied to analyse the Short Channel Effects (SCEs) of JL NT MOSFET. The electrical performance of proposed device has been investigated by varying different process parameters such as silicon nanotube thickness, gate oxide thickness, and gate length. All the results of developed models have been validated by comparing with so obtained simulated results from genius 3D device simulator of VisualTCAD for different device parameters. JLNT MOSFET with appropriate design parameters can be further explored for circuit applications.

Novel DOT1L ReceptorNatural Inhibitors Involved in Mixed Lineage Leukemia: a Virtual Screening, Molecular Docking and Dynamics Simulation Study

Raj, Utkarsh,Kumar, Himansu,Gupta, Saurabh,Varadwaj, Pritish Kumar Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

Background: The human protein methyl-transferase DOT1L catalyzes the methylation of histone H3 on lysine 79 (H3K79) at homeobox genes and is also involved in a number of significant processes ranging from gene expression to DNA-damage response and cell cycle progression. Inhibition of DOT1L activity by shRNA or small-molecule inhibitors has been established to prevent proliferation of various MLL-rearranged leukemia cells in vitro, establishing DOT1L an attractive therapeutic target for mixed lineage leukemia (MLL). Most of the drugs currently in use for the MLL treatment are reported to have low efficacy, hence this study focused on various natural compounds which exhibit minimal toxic effects and high efficacy for the target receptor. Materials and Methods: Structures of human protein methyl-transferase DOT1L and natural compound databases were downloaded from various sources. Virtual screening, molecular docking, dynamics simulation and drug likeness studies were performed for those natural compounds to evaluate and analyze their anti-cancer activity. Results: The top five screened compounds possessing good binding affinity were identified as potential high affinity inhibitors against DOT1L's active site. The top ranking molecule amongst the screened ligands had a Glide g-score of -10.940 kcal/mol and Glide e-model score of -86.011 with 5 hydrogen bonds and 12 hydrophobic contacts. This ligand's behaviour also showed consistency during the simulation of protein-ligand complex for 20000 ps, which is indicative of its stability in the receptor pocket. Conclusions: The ligand obtained out of this screening study can be considered as a potential inhibitor for DOT1L and further can be treated as a lead for the drug designing pipeline.

Development of ciclopirox nail lacquer with enhanced permeation and retention

Raj Kumar Thapa,최주연,고도경,강민형,한상덕,전준호,손미원,용철순,김종오 대한약학회 2016 Archives of Pharmacal Research Vol.39 No.7

Onychomycosis is a prevailing disease caused by fungal infection of nails that mostly affects athletes and the elderly. Ciclopirox is approved by the US Food and Drug Administration for the topical treatment of onychomycosis. However, the desired penetration of ciclopirox into the nail bed has not been achieved via topical application for efficient treatment. Therefore, the main aim of this study was to enhance ciclopirox permeation and retention in nail by the development of a new nail lacquer formulation. We screened the effects of different solvents, alkalizing agents, and permeation enhancers on the permeation of bovine hooves by ciclopirox and its retention in human nail clippings. The results suggest that isopropyl alcohol, potassium hydroxide, and urea as the solvent, alkalizing agent, and permeation enhancer, respectively, improved the permeation of the ciclopirox nail lacquer formulation the most with high flux rates. Comparison of the final formulation and marketed product revealed enhanced retention of ciclopirox from our developed formulation in human nail clippings. Therefore, our newly developed nail lacquer may be a potentially effective formulation for the treatment of onychomycosis in humans.

Endoplasmic Reticulum Stress and Cancer

Raj Kumar Yadav,채수완,김형룡,채한정 대한암예방학회 2014 Journal of cancer prevention Vol.19 No.2

The endoplasmic reticulum (ER) is the principal organelle responsible for multiple cellular functions including protein folding and maturation and the maintenance of cellular homeostasis. ER stress is activated by a variety of factors and triggers the unfolded protein response (UPR), which restores homeostasis or activates cell death. Multiple studies have clarified the link between ER stress and cancer, and particularly the involvement of the UPR. The UPR seems to adjust the paradoxical microenvironment of cancer and, as such, is one of resistance mechanisms against cancer therapy. This review describes the activity of different UPRs involved in tumorigenesis and resistanceto cancer therapy.

Ionic liquid assisted recovery of cobalt and nickel metals from spent lithium-ion batteries (LIBs)

( Raj Tirath ),( Raj Morya ),( Ashutosh Kumar Pandey ),( Sang-hyoun Kim ) 한국폐기물자원순환학회 2022 ISSE 초록집 Vol.2022 No.-

Lithium-ion batteries (LIBs) have become an essential component of the energy supply chain for transportation (in electric vehicles) and renewable energy storage systems. This surge in demand necessitates an increase in production, which, in turn, results in a large number of waste LIBs. LIB cathode material primarily contains heavy metal elements such as nickel (Ni) and cobalt (Co), which are potentially hazardous to human health and the environment if discarded improperly. The leaching of Co and Ni into various water streams has become an environmental hazard and is continuously affecting human health through the food chain. Thus, recycling spent LIBs has gotten a lot of attention because it provides a cost-effective way to ensure a steady supply of these metals for LIB remanufacturing. Thus, recycling spent LIBs has received a lot of attention because it offers a cost-effective way to ensure a steady supply of these metals for LIB remanufacturing while also encouraging safer environmental load reduction. Solvent extraction is the most widely accepted method for separating these metals, but traditional extractants employed in conjunction with molecular diluents often lack selectivity and cause major environmental hurdles. Thus, the present study demonstrated a state-of-the-art approach for the recovery of cobalt and nickel from waste LIBs using green ionic liquids, which is such as recycling from a sustainable perspective. Ionic liquids are molten salts of organic cation and inorganic/ organic anion and are considered as green solvents. Here in, two halogen-free, low viscous, biocompatible fatty acid-based hydrophobic ionic liquids (ILs) were synthesized, characterized, and used to recover cobalt, Co(II), and nickel, Ni(II), from aqueous solutions. The extraction behaviors of Co(II) and Ni(II) were studied further by varying the equilibrium time, ILs molar concentration, metal loading, and temperature. Thermodynamic parameters such as enthalpy change and Gibbs free energy change were also investigated showed that metal recovery is governed by metal transfer phenomenon. Study revealed that fatty acid-based ILs were found to be capable of extracting > 99 % Co(II) and Ni(II) from aqueous solutions at 298 K in 15 minutes using a 1:1 (org: aq.) ratio at low concentrations of 2.5 to 10 g L^-1. Furthermore, when the metal concentration was greater than 10 g L^-1, Co(II) extraction was preferred over Ni(II) extraction for methyltrioctylammonium oleate IL.

Modulation of Phenolic Content and Antioxidant Activity of Maize by Solid State Fermentation with Thamnidium elegans CCF 1456

Raj Kumar Salar,Milan Certik,Vlasta Brezova 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.1

Thamnidium elegans CCF 1456, a filamentous fungus, was used to enhance the total phenolic content and radical scavenging activity of maize via solid-state fermentation. Thamnidium fermented maize (TFM) and unfermented maize (UFM) grains were extracted with 65%ethanol and dimethylsulfoxide (DMSO). Total phenolic content (TPC), and radical scavenging capacity – determined with 1,1-diphenyl-2-picrylhydrazyl (DPPH) and radical cations of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS•+) found for TFM – were significantly (P < 0.05) higher on the 5th day of incubation than that of UFM extracts. A linear correlation was observed among TPC, DPPH and ABTS scavenging activities, and also among TPC and various carbohydrate-cleaving enzymes (α-amylase, β-glucosidase and xylanase), suggesting that this? strategy may help to enrich? TFM with improved phytochemical properties and antioxidant activities. Thamnidium elegans CCF 1456, a filamentous fungus, was used to enhance the total phenolic content and radical scavenging activity of maize via solid-state fermentation. Thamnidium fermented maize (TFM) and unfermented maize (UFM) grains were extracted with 65%ethanol and dimethylsulfoxide (DMSO). Total phenolic content (TPC), and radical scavenging capacity – determined with 1,1-diphenyl-2-picrylhydrazyl (DPPH) and radical cations of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS•+) found for TFM – were significantly (P < 0.05) higher on the 5th day of incubation than that of UFM extracts. A linear correlation was observed among TPC, DPPH and ABTS scavenging activities, and also among TPC and various carbohydrate-cleaving enzymes (α-amylase, β-glucosidase and xylanase), suggesting that this? strategy may help to enrich? TFM with improved phytochemical properties and antioxidant activities.

Estimation and validation of maxwell stress of planar dielectric elastomer actuators

Raj Kumar Sahu,Abhishek Saini,Dilshad Ahmad,Karali Patra,Jerzy Szpunar 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.1

In this paper, Maxwell stress of circular planar actuator at different applied voltages was estimated and then validated with the uniaxialcompression test of three different dielectric elastomers (VHB, silicone and natural rubber). Pelrine’s equation was revisited to estimateMaxwell stress which causes the actuation in the planar direction. More precise and accurate estimation of Maxwell stress could be madein this work by considering variation of dielectric constant with respect to frequency and pre-strain. Estimated Maxwell stress was validatedthrough (i) out-of-plane strain or thickness strain obtained from measured area strain considering constant volume deformation, and(ii) out-of-plane mechanical compressive test results. The estimated Maxwell stress agrees well with the corresponding experimentalcompressive stress values for different pre-straining cases considered in this work.

Impact of instream sand mining on habitat destruction or transformation using coupling models of HSI and MLR

Raj Kumar Bhattacharya,Nilanjana Das Chatterjee,Kousik Das 대한공간정보학회 2020 Spatial Information Research Vol.28 No.1

Several human activities like sand mining, dam construction have intensive effect on river ecosystem. Instream sand mining is one of them to hindrance on riverine biota. Hence, an attempt is made in this study to assess three tier habitat degradation or alteration caused by instream sand mining from channel bed to riparian and bank site in upper, middle and lower segments of Kangsabati River. Habitat Suitability Index (HSI) is applied to detect geo referenced ecological information on two different condition i.e. habitat suitability of two dominating species of Koeleria macrantha and Cynodon dactylon (pre mining) and degraded or altered habitat incorporated with mining responses (post mining). HSI prepared five different suitable class taken seven dominating variables i.e. river channel, sandchar, riparian zone, slope, elevation, dry and moist sand layer using multiple logistic regressions (MLR) under GIS platform. MLR denotes sandchar deposition, elevation as significant variables of Koeleriamacrantha dominance along the bank while moist sand layer, riparian zone signified on Cynodondactylon dominance across the riparian site. HSI indicates lowsuitable class of Koeleriamacrantha and Cynodondactylon dominated in largest sand mining area as lower (82%, 86%), middle (58%, 89%) and upper segment (77%, 78%) whereas largest mining area under two dominant species reaches low-suitable class as lower (79%, 58%), middle (89%, 82%) and upper segment (92%, 70%) respectively. In spite of variables influence on species dominance, massive sand mining leads to destroy the habitat suitability. Therefore, in situ habitat suitability of dominant species either degraded or altered throughout the channel.

Effect of process parameters on the recovery of thorium tetrafl uoride prepared by hydrofl uorination of thorium oxide, and their optimization

Raj Kumar,Sonal Gupta,Sourabh Wajhal,S.K. Satpati,M.L. Sahu 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.5

Liquid fueled molten salt reactors (MSRs) have seen renewed interest because of their inherent safetyfeatures, higher thermal efficiency and potential for efficient thorium utilisation for power generation. Thorium fluoride is one of the salts used in liquid fueled MSRs employing TheU cycle. In the presentstudy, ThF4 was prepared by hydro-fluorination of ThO2 using anhydrous HF gas. Process parameters viz. bed depth, hydrofluorination time and hydrofluorination temperature, were optimized for the preparation of ThF4 in a static bed reactor setup. The products were characterized with X-Ray diffraction andexperimental conditions for complete conversion to ThF4 were established which also corroborated withthe yield values. Hydrofluorination of ThO2 at 450 C for half an hour at a bed depth of 6 mm gave thebest result, with a yield of about 99.36% ThF4. No unconverted oxide or any other impurity was observed. Rietveld refinement was performed on the XRD data of this ThF4, and Chi2 value of 3.54 indicated goodagreement between observed and calculated profiles.

An approach for quantification of friction and enhancing the process efficiency during polishing of optical glass

Raj Kumar Pal,Rohit Sharma,Prabhat Kumar Baghel,Harry Garg,Vinod Karar 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.8

Quantification of friction may provide insights into the material removal behavior of polishing process. In this study, frictional force at the workpiece-polisher interface is measured using customised instrumentation setup (miniature load cell: 0-25 lbf) at different combinations of process parameters during polishing of BK7 optical glass. It is observed that frictional force varies with polishing time and is also a function of process parameters. It is observed that friction coefficient (~0.1) indicates the ductile material removal from the workpiece surface while friction coefficient (~0.3) indicates ductile cum brittle fracture behavior, which is also verified through surface texture observed through optical interferometer. Friction coefficient indicates that workpiece and polisher surfaces are in solid-solid contact mode. Hence, mechanical actions are dominant over chemical actions in removing the material from workpiece surface. Further variation of surface parameters w.r.t. wear index is estimated and way to enhance the polishing process efficiency is suggested.