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31.
Y. V. Auchynnikau N. M. Chekan V. A. Struk Y. I. Eisymont N. V. Malay 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2014,8(5):887-893
The impact of microwave radiation and heat treatment on the structure, morphology, and physical and mechanical properties of diamond-like coatings is studied; recrystallization of the coating structure is revealed. It is ascertained that microwave irradiation of diamond-like coatings changes their physical and mechanical properties. 相似文献
32.
This paper presents a new image retrieval scheme using visually significant point features. The clusters of points around significant curvature regions (high, medium, and weak type) are extracted using a fuzzy set theoretic approach. Some invariant color features are computed from these points to evaluate the similarity between images. A set of relevant and non-redundant features is selected using the mutual information based minimum redundancy-maximum relevance framework. The relative importance of each feature is evaluated using a fuzzy entropy based measure, which is computed from the sets of retrieved images marked relevant and irrelevant by the users. The performance of the system is evaluated using different sets of examples from a general purpose image database. The robustness of the system is also shown when the images undergo different transformations. 相似文献
33.
Haldar B Chakrabarty A Mallick A Mandal MC Das P Chattopadhyay N 《Langmuir : the ACS journal of surfaces and colloids》2006,22(8):3514-3520
Steady-state fluorescence measurements and isothermal titration calorimetric experiments have been performed to study the interaction between a telechelic polymer, pyrene-end-capped poly(ethylene oxide) (PYPY), and sodium alkyl sulfate surfactants having decyl, dodecyl, and tetradecyl hydrocarbon tails. Fluorometric results suggest polymer-surfactant interaction in the very low range of polymer concentrations. The relative variation in the excimer to monomer pyrene emission intensities with varying surfactant concentration reveals that initial addition of surfactant favors intramolecular preassociation until the surfactant molecules start binding with the ethylene oxide (EO) chain. With the growing number of surfactant aggregates along the EO chain, the association becomes hindered due to the polyelectrolyte effect. The results from microcalorimetric titrations in the low concentration range of PYPY solution (approximately 10(-6) M) with alkyl sulfates suggest two kinds of surfactant-polymer interactions, one with the polymer hydrophobic end groups and the other with the ethylene oxide backbone. The overall polymer-surfactant interaction starts at a much lower surfactant concentration for the hydrophobically modified polymers compared to that in the case of unsubstituted poly(ethylene oxide) homopolymer. From the experiments critical aggregation concentration values and the second critical concentration where free micelles start forming have been determined. An endeavor has been made to unveil the mechanism underlying the corresponding associations of the surfactants with the polymer. 相似文献
34.
[reaction: see text] Asymmetric reductive ring opening of oxa- and azabenzonorbornadienes with organic acids and zinc powder under mild conditions catalyzed by Ni(binap)Cl(2) or Pd(binap)I(2) produces the corresponding 1,2-dihydronaphth-1-ols in good to excellent yields with high enantioselectivity. 相似文献
35.
The maximum clique problem is an important problem in graph theory. Many real-life problems are still being mapped into this problem for their effective solutions. A natural extension of this problem that has emerged very recently in many real-life networks, is its fuzzification. The problem of finding the maximum fuzzy clique has been formalized on fuzzy graphs and subsequently addressed in this paper. It has been shown here that the problem reduces to an unconstrained quadratic 0–1 programming problem. Using a maximum neural network, along with mutation capability of genetic adaptive systems, the reduced problem has been solved. Empirical studies have been done by applying the method on stock flow graphs to identify the collusion set, which contains a group of traders performing unfair trading among themselves. Additionally, it has been applied on a gene co-expression network to find out significant gene modules and on some benchmark graphs. 相似文献
36.
37.
Malay Ghosh 《Annals of the Institute of Statistical Mathematics》1975,27(1):57-68
Summary The object of the present investigation is to study some properties of a class of Spearman rank statistics and to apply these
results in studying the properties of a sequential procedure proposed in Section 3. The problem is one of bounded length confidence
intervals for simple regression coefficients in linear models where both variables are subject to error. It is shown that
the proposed procedure is asymptotically ‘consistent’ and ‘efficient’ in the sense of Chow and Robbins [3]. 相似文献
38.
39.
A Potent Glucose–Platinum Conjugate Exploits Glucose Transporters and Preferentially Accumulates in Cancer Cells 下载免费PDF全文
Dr. Malay Patra Dr. Timothy C. Johnstone Dr. Kogularamanan Suntharalingam Prof. Stephen J. Lippard 《Angewandte Chemie (International ed. in English)》2016,55(7):2550-2554
Three rationally designed glucose–platinum conjugates (Glc–Pts) were synthesized and their biological activities evaluated. The Glc–Pts, 1 – 3 , exhibit high levels of cytotoxicity toward a panel of cancer cells. The subcellular target and cellular uptake mechanism of the Glc–Pts were elucidated. For uptake into cells, Glc–Pt 1 exploits both glucose and organic cation transporters, both widely overexpressed in cancer. Compound 1 preferentially accumulates in and annihilates cancer, compared to normal epithelial, cells in vitro. 相似文献
40.
Organometallic Derivatization of the Nematocidal Drug Monepantel Leads to Promising Antiparasitic Drug Candidates 下载免费PDF全文
Jeannine Hess Dr. Malay Patra Dr. Loganathan Rangasamy Sandro Konatschnig Dr. Olivier Blacque Dr. Abdul Jabbar Patrick Mac Dr. Erik M. Jorgensen Prof. Dr. Robin B. Gasser Prof. Dr. Gilles Gasser 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(46):16602-16612
The discovery of novel drugs against animal parasites is in high demand due to drug‐resistance problems encountered around the world. Herein, the synthesis and characterization of 27 organic and organometallic derivatives of the recently launched nematocidal drug monepantel (Zolvix®) are described. The compounds were isolated as racemates and were characterized by 1H, 13C, and 19F NMR spectroscopy, mass spectrometry, and IR spectroscopy, and their purity was verified by microanalysis. The molecular structures of nine compounds were confirmed by X‐ray crystallography. The anthelmintic activity of the newly designed analogues was evaluated in vitro against the economically important parasites Haemonchus contortus and Trichostrongylus colubriformis. Moderate nematocidal activity was observed for nine of the 27 compounds. Three compounds were confirmed as potentiators of a known monepantel target, the ACR‐23 ion channel. Production of reactive oxygen species may confer secondary activity to the organometallic analogues. Two compounds, namely, an organic precursor ( 3 a ) and a cymantrene analogue ( 9 a ), showed activities against microfilariae of Dirofilaria immitis in the low microgram per milliliter range. 相似文献