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Thakur Prasad Yadav

Bio: Thakur Prasad Yadav is an academic researcher from Banaras Hindu University. The author has contributed to research in topics: Alloy & Ball mill. The author has an hindex of 22, co-authored 121 publications receiving 2093 citations. Previous affiliations of Thakur Prasad Yadav include University of Liverpool & Rice University.


Papers
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Journal ArticleDOI
TL;DR: A systematic view of the basic concept of mechanical milling, historical view and appli- cations of mechanical milling in the synthesis of various nanomaterials, nanosomposites, nnaocarbons and nano quasicrystalline materials is presented in this paper.
Abstract: Synthesis of nanomaterials by a simple, low cost and in high yield has been a great challenge since the very early development of nanoscience. Various bottom and top down approaches have been developed so far, for the commercial production of nanomaterials. Among all top down approaches, high energy ball milling, has been widely exploited for the synthesis of various nanomaterials, nanograins, nanoalloy, nanocomposites and nano -quasicrystalline materials. Mechanical alloying techniques have been utilized to produce amorphous and nanocrystalline alloys as well as metal/non-metal nano- composite materials by milling and post annealing, of elemental or compound powders in an inert atmosphere. Mechanical alloying is a non-equilibrium processing technique in which different elemental powders are milled in an inert atmosphere to create one mixed powder with the same composition as the constituents. In high-energy ball milling, plastic deformation, cold-welding and fracture are predominant factors, in which the deformation leads to a change in particle shape, cold-welding leads to an increase in particle size and fracture leads to decrease in particle size resulting in the formation of fine dispersed alloying particles in the grain-refined soft matrix. By utilizing mechanical milling various kind of aluminium/ nickel/ mag- nesium/ copper based nanoalloys, wear resistant spray coatings, oxide and carbide strengthened aluminium alloys, and many other nanocomposites have been synthesized in very high yield. The mechanical milling has been utilized for the synthesis of nanomaterials either by milling and post annealing or by mechanical activation and then applying some other process on these activated materials. This review is a systematic view of the basic concept of mechanical milling, historical view and appli- cations of mechanical milling in the synthesis of various nanomaterials, nanosomposites, nnaocarbons and nano quasicrys- talline materials.

431 citations

Journal ArticleDOI
TL;DR: The results of these experiments clearly demonstrate that f-CNT-AmB has significantly greater antileishmanial efficacy than AmB and had no significant cytotoxic effects.
Abstract: Methods: f-CNTs were prepared in a two-step chemical carboxylation and amidation process. The AmB was then attached to make f-CNT‐AmB and its construction was confirmed by Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM). The cytotoxicity of the constructed compound, f-CNT‐AmB, was assessed in vitro using the J774A.1 macrophage cell line and in vivo using healthy BALB/c mice. Antileishmanial activity of AmB and f-CNT‐AmB was assessed in vitro using a macrophage (J774A.1 cell line) model of Leishmania donovani infection. Antileishmanial activity was assessed in vivo by comparing the parasite load of hamsters treated with a 5 day course of AmB, f-CNTs or f-CNT‐AmB initiated at 30 days after infection with L. donovani parasites. Results: The FTIR spectroscopy and TEM data demonstrate the successful attachment of AmB to f-CNTs. The in vitro cytotoxicity of AmB, f-CNTs and f-CNT‐AmB was measured by the cytotoxic concentration required to kill 50% of the cells: 0.48+0.06 mg/mL; 7.31+1.16 mg/mL; 0.66+0.17 mg/mL, respectively, in the J774A.1 cell line. The in vivo toxicity assessment of the compounds in BALB/c mice revealed no hepatic or renal toxicity. Against intracellular amastigotes the in vitro antileishmanial efficacy of f-CNT‐AmB was significantly higher than that of AmB (IC50 0.00234+0.00075 mg/mL versus 0.03263+0.00123 mg/mL; P ≤0.0001). The percentage inhibition of amastigote replication in hamsters treated with f-CNT‐AmB was significantly more than that with AmB (89.85%+2.93% versus 68.97%+1.84%; P¼0.0004). Conclusions: The results of these experiments clearly demonstrate that f-CNT‐AmB has significantly greater antileishmanial efficacy than AmB and had no significant cytotoxic effects.

139 citations

Journal ArticleDOI
TL;DR: In this paper, a multifunctional and recyclable membrane by intercalating gold nanoparticles and graphitic carbon nitride into graphene oxide (GNPs/g-C3N4/GO) is fabricated.
Abstract: Toxic organic pollutants in the aquatic environment cause severe threats to both humans and the global environment. Thus, the development of robust strategies for detection and removal of these organic pollutants is essential. For this purpose, a multifunctional and recyclable membrane by intercalating gold nanoparticles and graphitic carbon nitride into graphene oxide (GNPs/g-C3N4/GO) is fabricated. The membranes exhibit not only superior surface enhanced Raman scattering (SERS) activity attributed to high preconcentration ability to analytes through π–π and electrostatic interactions, but also excellent catalytic activity due to the enhanced electron–hole separation efficiency. These outstanding properties allow the membrane to be used for highly sensitive detection of rhodamine 6G with a limit of detection of 5.0 × 10−14m and self-cleaning by photocatalytic degradation of the adsorbed analytes into inorganic small molecules, thus achieving recyclable SERS application. Furthermore, the excellent SERS activity of the membrane is demonstrated by detection of 4-chlorophenol at less than nanomolar level and no significant SERS or catalytic activity loss was observed when reusability is tested. These results suggest that the GNPs/g-C3N4/GO membrane provides a new strategy for eliminating traditional, single-use SERS substrates, and expands practical SERS application to simultaneous detection and removal of environmental pollutants.

129 citations

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TL;DR: In this article, the green and sustainable synthesis of zinc oxide quantum dots (QDs) using zinc acetate (precursor) and Eclipta alba leaf extract as a reducing agent was monitored by ultraviolet-visible absorption spectroscopy at wavelength (λmax) 324.

81 citations

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TL;DR: This study has shown that this novel formulation of AmB can be administered orally, resulting in 99% inhibition of parasite growth following a 5-day course at 15 mg/kg body weight.
Abstract: Amphotericin B (AmB), is a highly effective antileishmanial agent used as first-line treatment in different formulations in visceral leishmaniasis endemic areas of Bihar, India. However, parenteral infusion, prolonged hospitalization, and toxicity are major hurdles. Our previous work demonstrated the efficacy and stability of functionalized carbon nanotubes as a delivery mechanism for AmB. In this study, using the hamster model, we have shown that this novel formulation of AmB can be administered orally, resulting in 99% inhibition of parasite growth following a 5-day course at 15 mg/kg body weight.

79 citations


Cited by
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01 May 1993
TL;DR: Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems.
Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

29,323 citations

Journal ArticleDOI
TL;DR: Various nanostructures, including liposomes, polymers, dendrimers, silicon or carbon materials, and magnetic nanoparticles, have been tested as carriers in drug delivery systems and their connections with drugs are analyzed.

1,007 citations

Journal ArticleDOI
29 Mar 2021
TL;DR: Nanomaterials have emerged as an amazing class of materials that consists of a broad spectrum of examples with at least one dimension in the range of 1 to 100 nm as discussed by the authors.
Abstract: Nanomaterials have emerged as an amazing class of materials that consists of a broad spectrum of examples with at least one dimension in the range of 1 to 100 nm. Exceptionally high surface areas can be achieved through the rational design of nanomaterials. Nanomaterials can be produced with outstanding magnetic, electrical, optical, mechanical, and catalytic properties that are substantially different from their bulk counterparts. The nanomaterial properties can be tuned as desired via precisely controlling the size, shape, synthesis conditions, and appropriate functionalization. This review discusses a brief history of nanomaterials and their use throughout history to trigger advances in nanotechnology development. In particular, we describe and define various terms relating to nanomaterials. Various nanomaterial synthesis methods, including top-down and bottom-up approaches, are discussed. The unique features of nanomaterials are highlighted throughout the review. This review describes advances in nanomaterials, specifically fullerenes, carbon nanotubes, graphene, carbon quantum dots, nanodiamonds, carbon nanohorns, nanoporous materials, core–shell nanoparticles, silicene, antimonene, MXenes, 2D MOF nanosheets, boron nitride nanosheets, layered double hydroxides, and metal-based nanomaterials. Finally, we conclude by discussing challenges and future perspectives relating to nanomaterials.

628 citations

Journal ArticleDOI
TL;DR: In this article, a review of different methods of nanoparticle preparations and its advantages, disadvantages, and applications is presented, which is categorized into two main types on as bottom up methods and top down methods depending on starting material of nanoparticles preparation.

573 citations

Journal ArticleDOI
TL;DR: The delivery of small molecule drugs is expounded, with special attention paid to the current progress of in vitro and in vivo research involving CNT-based DDSs, before finally concluding with some consideration on inevitable complications that hamper successful disease intervention with CNTs.

488 citations