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131.
132.
L. W. Lawrence Woo Paul M. Wood Christian Bubert Mark P. Thomas Atul Purohit Barry V. L. Potter 《ChemMedChem》2013,8(5):779-799
4‐{[(4‐Cyanophenyl)(4H‐1,2,4‐triazol‐4‐yl)amino]methyl}phenyl sulfamate and its ortho‐halogenated (F, Cl, Br) derivatives are first‐generation dual aromatase and sulfatase inhibitors (DASIs). Structure–activity relationship studies were performed on these compounds, and various modifications were made to their structures involving relocation of the halogen atom, introduction of more halogen atoms, replacement of the halogen with another group, replacement of the methylene linker with a difluoromethylene linker, replacement of the para‐cyanophenyl ring with other ring structures, and replacement of the triazolyl group with an imidazolyl group. The most potent in vitro DASI discovered is an imidazole derivative with IC50 values against aromatase and steroid sulfatase in a JEG‐3 cell preparation of 0.2 and 2.5 nM , respectively. The parent phenol of this compound inhibits aromatase with an IC50 value of 0.028 nM in the same assay. 相似文献
133.
Chirag Modi Dhiren Patel Bhavesh Borisaniya Avi Patel Muttukrishnan Rajarajan 《The Journal of supercomputing》2013,63(2):561-592
Cloud computing offers scalable on-demand services to consumers with greater flexibility and lesser infrastructure investment. Since Cloud services are delivered using classical network protocols and formats over the Internet, implicit vulnerabilities existing in these protocols as well as threats introduced by newer architectures raise many security and privacy concerns. In this paper, we survey the factors affecting Cloud computing adoption, vulnerabilities and attacks, and identify relevant solution directives to strengthen security and privacy in the Cloud environment. 相似文献
134.
M. Kumar G. K. Gupta O. P. Modi B. K. Prasad A. K. Khare M. Sharma 《Canadian Metallurgical Quarterly》2017,56(1):58-66
The present work compares the properties of the Cu–TiB2 composites prepared by varying the mechanical milling conditions. The Cu–TiB2 composites were processed using Cu–TiB2 powders combined milling, a powder mixture consisting of separately milled Cu & TiB2 and a powder mixture prepared by the combination of separate and combined milling. The hardness and flexural strength of the combined milled powders were found to be maximum, despite of their lower sintered density. The separately milled powders achieved excellent electrical properties combined with moderate hardness and flexural strength. The properties of composites processed using the combination of separate and combined milling laid in between the two conditions of combined and separate milling. 相似文献
135.
Shuo-Hsien Cheng Shu-Hua Chou Wen-Yi Hung Hong-Wei You You-Ming Chen Atul Chaskar Yi-Hung Liu Ken-Tsung Wong 《Organic Electronics》2013,14(4):1086-1093
A series of new bipolar hosts C1O1, C2O1, and C1O2 comprising hole-transporting carbazole as donor (D) and electron-transporting oxadiazole as acceptor (A) have been designed and synthesized to tune D/A ratio with a view for getting in-depth information about structure–property–performance relationship. The D/A ratio exerts subtle influences on absorption spectra and energy levels. Time-of-flight (TOF) measurements reveal that the increment of donor units effectively increase the hole mobility. The appropriate energy levels and triplet energies along with promising morphological and thermal stability of these molecules bring out them as suitable hosts to realize green PhOLEDs with (PBi)2Ir(acac) and (PPy)2Ir(acac) emitters. Green phosphorescent devices hosted by C1O1, C2O1, and C1O2 achieved maximum external quantum efficiencies of 20.7%, 20.4%, and 17.3%, respectively. These results indicate that carbazole/oxadiazole hybrid molecule with one carbazole and oxadiazole each is a better candidate for highly efficient green PhOLEDs. 相似文献
136.
A number of sulfur analogs of polynuclear aromatic hydrocarbons (thia-PAHs) have been identified in cigarette smoke condensate. Phenanthro[3,4-b]thiophene (P[3,4-b]T) and phenanthro[4,3-b]thiophene (P[4,3-b]T) are sulfur analogs of benzo[c]phenanthrene, which is known to be metabolized to one of the most tumorigenic fjord region diol epoxides tested thus far. Although fjord region diol epoxides of P[3,4-b]T and P[4,3-b]T are expected to be potent mutagens and tumorigens, these two thia-PAHs differ greatly in their mutagenic potencies. In contrast to P[3,4-b]T which is as mutagenic as benzo[a]pyrene, its isoster P[4,3-b]T is a nonmutagenic compound. In order to understand the basis underlying the difference in the mutagenic potency of P[3,4-b]T and P[4,3-b]T, we require these thia-PAHs and their dihydrodiol derivatives for investigating their metabolism and mutagenic/carcinogenic activity. In these studies, we have investigated the Suzuki cross-coupling reaction for an abbreviated synthesis of P[3,4-b]T, P[4,3-b]T, and their dihydrodiol derivatives from easily available reagents. 相似文献
137.
N.H. Vasoya L.H. VanpariyaP.N. Sakariya M.D. TimbadiyaT.K. Pathak V.K. LakhaniK.B. Modi 《Ceramics International》2010
Mechanical milling induced structural property modifications in Ni0.5Zn0.5Fe2O4 spinel ferrite have been studied. We have observed two interesting phenomena (i) “temperature diffuse scattering” due to displacement of atoms from their mean position and (ii) appearance and gradual evolution of (4 2 0) plane in X-ray diffraction profiles and increase in average percentage disagreement between observed and calculated intensity ratios value, due to “preferred grain orientation.” Both these effects get prominent with milling time. The X-ray diffraction line intensity calculations revealed large B-site occupancy of Zn2+-ions, mainly due to modified synthesis procedure employed. The grain orientation factor increases from 10.6% to 18.1% on milling. It is found that milling has marked influence on various parameters: lattice constant, grain size, stress–strain, surface area and energy. 相似文献
138.
Evaluation of performance of nanofluid using multiwalled carbon nanotubes for machining of Ti–6AL–4V
Neelesh Kumar Sahu Atul B. Andhare Roja Abraham Raju 《Machining Science and Technology》2018,22(3):476-492
Machining of titanium alloys generate very high temperature in the cutting zone. This results in rapid tool wear and poor surface properties. Therefore, improvement in cutting performance in machining of titanium alloys is very much dependent on effectiveness of the cooling strategies applied. In the present work, performance of nanofluid using multiwalled carbon nanotubes (MWCNTs) dispersed in distilled water and sodium dodecyl sulfate (SDS) as surfactant is evaluated for turning operation on Ti–6Al–4V workpieces. Turning operations were carried out under three different conditions – dry, with conventional cutting fluid and with nanofluid. Nanofluid application was limited to 1 L/h and it was applied at the tool tip through gravity feed. Various machining responses like cutting force, surface finish and tool wear were analyzed while turning at optimum cutting parameters as 150 m/min, 0.1 mm/rev and 1 mm depth of cut. Later on, machining performance of nanofluid is confirmed at low cutting speed of 90 m/min. Nanofluid outperformed conventional cutting fluid with 34% reduction in tool wear, average 28% drop in cutting forces and 7% decrease in surface roughness at cutting speed of 150 m/min. 相似文献
139.
Bharde A Rautaray D Bansal V Ahmad A Sarkar I Yusuf SM Sanyal M Sastry M 《Small (Weinheim an der Bergstrasse, Germany)》2006,2(1):135-141
The development of synthetic processes for oxide nanomaterials is an issue of considerable topical interest. While a number of chemical methods are available and are extensively used, the collaborations are often energy intensive and employ toxic chemicals. On the other hand, the synthesis of inorganic materials by biological systems is characterized by processes that occur at close to ambient temperatures and pressures, and at neutral pH (examples include magnetotactic bacteria, diatoms, and S-layer bacteria). Here we show that nanoparticulate magnetite may be produced at room temperature extracellularly by challenging the fungi, Fusarium oxysporum and Verticillium sp., with mixtures of ferric and ferrous salts. Extracellular hydrolysis of the anionic iron complexes by cationic proteins secreted by the fungi results in the room-temperature synthesis of crystalline magnetite particles that exhibit a signature of a ferrimagnetic transition with a negligible amount of spontaneous magnetization at low temperature. 相似文献
140.
Modi K Fazio R Pascazio S Vedral V Yuasa K 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2012,370(1976):4810-4820
We construct a quantumness witness following the work of Alicki & van Ryn (AvR). We reformulate the AvR test by defining it for quantum states rather than for observables. This allows us to identify the necessary quantities and resources to detect quantumness for any given system. The first quantity turns out to be the purity of the system. When applying the witness to a system with even moderate mixedness, the protocol is unable to reveal any quantumness. We then show that having many copies of the system leads the witness to reveal quantumness. This seems contrary to the Bohr correspondence, which asserts that, in the large-number limit, quantum systems become classical, whereas the witness shows quantumness when several non-quantum systems, as determined by the witness, are considered together. However, the resources required to detect the quantumness increase dramatically with the number of systems. We apply the quantumness witness for systems that are highly mixed but in the large-number limit that resembles nuclear magnetic resonance (NMR) systems. We make several conclusions about detecting quantumness in NMR-like systems. 相似文献