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91.
Prakash Shetty 《Surface Engineering and Applied Electrochemistry》2017,53(6):587-591
This paper summarizes the inhibitor activity of various reported thiourea derivatives in acid media used against the deterioration of mild steel. Acid solutions have been extensively employed in manufacturing and many industrial processes for pickling and removal of undesirable scale. Mild steel is highly susceptible to corrosion in such aggressive acid media. The additives such as inhibitors are widely employed in those cases to reduce the extent of corrosion as much as possible. The survey of literature on organic inhibitors clearly indicates the potential usage of thiourea derivatives as inhibitors of mild steel corrosion. The influence of physical-chemical properties on the inhibition activity of thiourea derivatives has been discussed. This information is highly useful for different industrial applications where good performing inhibitors are being required for protecting mild steel from aggressive acid media. 相似文献
92.
S. Vinodh N. Hari Prakash K. Eazhil Selvan 《The International Journal of Advanced Manufacturing Technology》2011,57(1-4):343-352
The modern manufacturing organizations are adopting lean manufacturing principles so as to eliminate wastes and streamline their processes. The evaluation of leanness gains vital importance. Multiple tools/techniques are available for ensuring leanness. Due to the impreciseness and vagueness associated with decision-making problems, fuzzy logic need to be used. Relational databases enable decision-making process. This article presents a study in which fuzzy association rules mining approach has been used for leanness evaluation of an Indian modular switches manufacturing organization. The experiences gained as a result of the conduct of the study indicated that leanness evaluation could be performed by the decision makers without any constraints. 相似文献
93.
Phase Evolution,Magnetic, Optical,and Dielectric Properties of Zr‐Substituted Bi0.9Gd0.1FeO3 Multiferroics
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Prakash Chandra Sati Manoj Kumar Sandeep Chhoker 《Journal of the American Ceramic Society》2015,98(6):1884-1890
Polycrystalline BiFeO3 (BFO) and Bi0.90Gd0.10Fe1?xZrxO3 (x = 0.0–0.10; BGFZx) ceramics were synthesized by solid‐state reaction method. Rietveld analysis of X‐ray diffraction patterns showed that BFO and BGFZx = 0.0 samples are stabilized in rhombohedral structure (space group R3c), whereas a small fraction of orthorhombic phase (space group Pn21a) is observed for BGFZx = 0.03–0.10 samples. Suppression and disappearance of some Raman modes indicated a structural phase transition with addition of Zr dopant at Fe site. Magnetic measurements exhibited weak ferromagnetic behavior of BGFZx samples with increasing Zr+4 concentrations. The insertion of Gd+3 ions at Bi+3 sites and nonmagnetic Zr+4 ions at Fe+3 sites in Fe–O–Fe network suppressed the spin cycloid structure of BFO which in turn enhanced the magnetization of these ceramics. Electron spin resonance spectra revealed the breaking of spin cycloid of BFO due to the development of free spins with addition of Zr+4 dopants at Fe sites. UV–Visible diffuse reflectance spectra showed one d–d crystal field transition and two charge‐transfer (C–T) transitions along with a sharp absorption of light in visible region for all samples. Almost frequency‐independent dielectric constant and dielectric loss along with very low values of dielectric loss indicated greatly improved dielectric properties for BGFZx = 0.03–0.10 samples. 相似文献
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96.
Prakash Parthasarathy Hang Seok Choi Hoon Chae Park Jae Gyu Hwang Ho Seong Yoo Byeong-Kyu Lee Mukesh Upadhyay 《Korean Journal of Chemical Engineering》2016,33(8):2268-2286
Waste tyres have become a grave concern as their accumulation is aggregating every year. Not only the size of waste tyre has to be reduced, but also some useful energy has to be recovered out of it as the world badly requires energy from alternate sources. Pyrolysis is one such method to extract energy potential products from waste tyres. It is extensively used to generate carbon black (solid product), tyre-oil (liquid product) and syngas (gas product) from waste tyres. In that connection, this article discusses the effect of various parameters on the product composition of pyrolysis of waste tyres. The current usage of pyrolysis products and their typical characteristics are also discussed in this critique. Of late, extraction of high value added products, such as activated carbon from carbon black, and limonene from tyre-oil is gaining attention. The article also throws some light on the application and generation routes of activated carbon and limonene from waste tyres. 相似文献
97.
98.
Nitroarenes as Antitubercular Agents: Stereoelectronic Modulation to Mitigate Mutagenicity
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Dr. Sudhir Landge Dr. Vasanthi Ramachandran Dr. Anupriya Kumar Dr. João Neres Kannan Murugan Dr. Claire Sadler Dr. Mick D. Fellows Vaishali Humnabadkar Dr. Prakash Vachaspati Dr. Anandkumar Raichurkar Sreevalli Sharma Sudha Ravishankar Supreeth Guptha Dr. Vasan K. Sambandamurthy Dr. Tanjore S. Balganesh Dr. Bheemarao G. Ugarkar Dr. V. Balasubramanian Dr. Balachandra S. Bandodkar Dr. Manoranjan Panda 《ChemMedChem》2016,11(3):331-339
Nitroarenes are less preferred in drug discovery due to their potential to be mutagenic. However, several nitroarenes were shown to be promising antitubercular agents with specific modes of action, namely, nitroimidazoles and benzothiazinones. The nitro group in these compounds is activated through different mechanisms, both enzymatic and non‐enzymatic, in mycobacteria prior to binding to the target of interest. From a whole‐cell screening program, we identified a novel lead nitrobenzothiazole (BT) series that acts by inhibition of decaprenylphosphoryl‐β‐d ‐ribose 2′‐epimerase (DprE1) of Mycobacterium tuberculosis (Mtb). The lead was found to be mutagenic to start with. Our efforts to mitigate mutagenicity resulted in the identification of 6‐methyl‐7‐nitro‐5‐(trifluoromethyl)‐1,3‐benzothiazoles (cBTs), a novel class of antitubercular agents that are non‐mutagenic and exhibit an improved safety profile. The methyl group ortho to the nitro group decreases the electron affinity of the series, and is hence responsible for the non‐mutagenic nature of these compounds. Additionally, the co‐crystal structure of cBT in complex with Mtb DprE1 established the mode of binding. This investigation led to a new non‐mutagenic antitubercular agent and demonstrates that the mutagenic nature of nitroarenes can be solved by modulation of stereoelectronic properties. 相似文献
99.
Pham Binh Thai Prakash Indra 《Bulletin of Engineering Geology and the Environment》2019,78(3):1911-1925
Bulletin of Engineering Geology and the Environment - Landslide susceptibility assessment was performed using the novel hybrid model Bagging-based Naïve Bayes Trees (BAGNBT) at Mu Cang Chai... 相似文献
100.
Pal Shaili Kumar Ajay Kumar Sunil De Arup Kumar Prakash Rajiv Sinha Indrajit 《Catalysis Letters》2022,152(11):3259-3271
Catalysis Letters - Magnetically recyclable visible light photocatalysts for the degradation of critical organic pollutants are an urgent industrial requirement. Nonetheless, one component... 相似文献