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11.
Mahendra Madegowda Doreswamy Beeranahally H. Sridhar Mandayam A. Prasad Javaregowda S. Khanum Shaukath A. Shashikanth Sheena Sudha Belagur S. 《Structural chemistry》2004,15(3):211-214
Benzophenone analog 3 has been synthesized and characterized by the X-ray diffraction (XRD) method. The compound crystallizes in a monoclinic space group P21/c with cell parameters a = 7.701(8) Å, b = 7.151(5) Å, c= 28.323(3) Å, = 104.639(4)°, Z = 4. The structure exhibits intra- and intermolecular hydrogen bonding of the type N–HO, C–HO, and N–HN. The molecules are interlinked through hydrogen bonds forming an infinite chain. This polymeric-like structure may play an important role in biological activity. 相似文献
12.
Deshabrata Roy Mahapatra Sankar Kumar Roy Mahendra Prasad Biswal 《Applied Mathematical Modelling》2013
In this paper a multi choice stochastic transportation problem is considered where the supply and demand parameters of the constraints follow extreme value distribution. Some of the cost coefficients of the objective function are multi-choice type. At first all the probabilistic constraints are transformed into deterministic constraints. Further using the binary variables, multi-choice type cost coefficients are handled. Then the transformed problem is considered as a deterministic multi-choice transportation problem. Finally, a numerical example is presented to illustrate the solution procedure. 相似文献
13.
Rehan Zahid Masjuki Bin Haji Hassan Mahendra Varman Riaz Ahmad Mufti Md. Abul Kalam Nurin Wahidah Binti Mohd Zulkifli 《固体与材料科学评论》2017,42(4):267-294
Tribological efficiency of industrial applications involving boundary lubrication regime can be improved to an appreciable extent by the deposition of hard coatings on interacting surfaces. Among such coatings, diamond-like carbon (DLC) coatings are considered to be one of the most suitable ones for the said role. DLC coatings possess a unique combination of physical, chemical, and material properties due to which they can help in minimizing friction-induced energy and material losses even under starved lubrication conditions. Since commercial lubricants are optimized for steel surfaces, therefore, a lot of experimental investigations were carried out to analyze the tribological compatibility of these lubricants with various DLC coatings. However, there is still a lack of understanding about how DLC coatings interact with conventional lubricant additives. Some researchers reported tribologically beneficial interactions between DLC coatings and formulated lubricants while others observed no such behavior. To address these inconsistencies, there is a need to rearrange the published data in a more apprehensible and organized manner with a special emphasis on the mechanisms responsible for a particular tribological behavior. In this way, it can be determined whether synergistic or antagonistic correlation exists between a particular DLC-lubricant combination and research on DLC coatings can be continued in a logical way. In this article, most widely investigated non-doped DLC coatings (ta-C, a-C:H, a-C, and ta-C:H) are tribologically analyzed. Average values of friction and wear coefficients are calculated for various DLC-lubricant combinations using already published data and compared to quantify the effectiveness of a particular lubricant additive in enhancing tribological characteristics of symmetrical non-doped DLC contacts. Moreover, tribological performance parameters of non-doped DLC coatings are compared with those of doped-DLC coatings to understand differences in their tribological behavior in combination with additives. 相似文献
14.
15.
B. H. Doreswamy Chandra K. Mantelingu M. A. Sridhar M. Mahendra 《Research on Chemical Intermediates》2014,40(8):2659-2665
The isolation of stable carbenes of the Arduengo and Wanzlick type has prompted us to look for stable nitrenium ions of the related structural type 1-Hydroxy-3-methyl benzotriazolium trifluromethane sulfonate. Nitrenium ions are azocations with structure and survive long enough under in vitro conditions to bind with biological nucleophiles, i.e. DNA bases, and play an important role in carcinogenic processes involving the metabolism of aromatic amines. The title compound (C15H16F3N6O5S) was isolated and crystallized in the monoclinic space group Cc with cell parameters a = 19.866(1) Å, b = 13.128(9) Å, c = 7.673(5) Å, and Z = 4. The structure has both intra- and intermolecular hydrogen bonds. 相似文献
16.
Dr. Mahendra K. Sharma Dr. Sebastian Blomeyer Beate Neumann Dr. Hans-Georg Stammler Priv.-Doz. Dr. Rajendra S. Ghadwal 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(35):8249-8253
The first divinyldiarsenes [{(NHC)C(Ph)}As]2 (NHC=IPr 3 a , SIPr 3 b ; IPr=C{(NAr)CH}2; SIPr=C{(NAr)CH2}2; Ar=2,6-iPr2C6H3) are reported. Compounds 3 a and 3 b were prepared by the reduction of corresponding chlorides {(NHC)C(Ph)}AsCl2 (NHC=IPr 2 a , SIPr 2 b ) with Mg. Calculations revealed a small HOMO–LUMO energy gap of 3.86 ( 3 a ) and 4.24 eV ( 3 b ). Treatment of 3 a with (Me2S)AuCl led to the cleavage of the As=As bond to restore 2 a , which is expected to proceed via the diarsane [{(IPr)C(Ph)}AsCl]2 ( 4 ). Remarkably, 4 as well as 2 a can be selectively accessed on treatment of 3 a with an appropriate amount of C2Cl6. Moreover, 3 a readily reacts with PhEEPh (E=Se or Te) at room temperature to give {(IPr)C(Ph)}As(EPh)2 (E=Se 5 a ; Te 5 b ), revealing the cleavage of As=As and E−E bonds and the formation of As−E bonds. Such highly selective stepwise oxidation ( 3 a → 4 → 2 a ) and bond metathesis ( 3 a → 5 a , b ) reactions are unprecedented in main-group chemistry. 相似文献
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18.
One of the key steps in the synthesis of ABT-431 is the diastereoselective cyclization of thieny alcohol 1 to trans amide 2. We report a detailed study of the influence of acids, solvents and temperature over the ratio of cis and trans diastereomers. 相似文献
19.
A simple and efficient synthesis of nickel(II) 2‐benzazolo‐5,10,15,20‐tetraphenylporphyrins from nickel(II) 2‐formyl‐5,10,15,20‐tetraphenylporphyrin and o‐arylenediamines, o‐aminophenols or o‐aminothiophenol in 1,2‐dichlorobenzene is described. A diverse range of novel β‐substituted azoloporphyrins has been successfully synthesized in good yields and their structures are confirmed on the basis of spectral data. J. Heterocyclic Chem., (2012). 相似文献
20.
Manjushree Senapati Narayan C. Samal Ranu Mishra Swoyam P. Rout Lalit N. Patnaik Mahendra K. Rout 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5-6):567-575
The present investigation aims at estimating the retarding effect of acetophenone in the polymerization of methyl methacrylate initiated by α,α' -azobisisobutyronitrile in the temperature range of 50 to 80°C. The results are interpreted in terms of Tüdös kinetic parameter (β). The effects of varying concentrations of substrate, monomer, initiator, and salts have been investigated. A suitable reaction scheme and rate expression have been suggested on the basis of the experimental findings, and another kinetic parameter (K) to represent the reactivity of acetophenones toward the polymer radical has been obtained graphically. 相似文献