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91.
Synthesis of titanium oxide film by plasma oxidization of the metallic films is investigated. Argon/oxygen gas mixture in the pressure range 30 × 10?2 mbar is used for plasma processing at a frequency of 250 kHz. The plasma‐oxidized films are annealed in a tube furnace in argon atmosphere to establish crystalline‐phase formation. X‐ray diffraction and Raman spectroscopic results manifest peaks corresponding to rutile TiO2. Ultraviolet‐Visible (UV‐Vis) spectroscopic analysis confirms the bandgap of rutile TiO2, and photoluminescence spectra exhibit peaks due to oxygen defects. Homogeneity across the film's thickness and the nature of the film substrate interface is studied by depth profiling acquired using secondary ion mass spectrometry. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
92.
Tamoghna Bhattacharyya Arumoy Chatterjee Budhaditya Chatterjee Sufi O. Raja Anjan Kr. Dasgupta 《Electrophoresis》2015,36(24):3009-3013
We report both the experimental and theoretical insights of differential electro‐diffusion behavior of carbon nanomaterials (e.g. single wall, multiwall carbon nanotubes, and graphene). We thus discriminate one from the other in a soft gel system. The differential mobility of such material depends on their intrinsic properties, both extend and rate of migration bearing the discriminatory signature. The mobility analysis is made by a real time monitoring of the respective bands. 相似文献
93.
Debabrata Chatterjee Namita Jaiswal Jagadeesh C. Bose K Ram Balak Mahato Diptendu Bhattacharyya 《Journal of Coordination Chemistry》2015,68(17-18):3229-3235
Reaction of [RuIII(EDTA)(CyS)]2? (edta4? = ethylenediaminetetraacetate; CySH = cysteine) with molecular oxygen (O2) has been studied as a function of pH (4.0–8.0) and cysteine concentration (0.2–2.0 mM) at room temperature (25 °C). Biological activities of the [Ru(EDTA)]/CySH/O2 system pertaining to cleavage of supercoiled plasmid DNA to its nicked open circular form has been explored in this work. Results are discussed in regard to the reaction of the ruthenium(III)-complex with molecular oxygen) and a working mechanism is proposed for the biological activities of the ruthenium(III)-complex in the presence of O2. 相似文献
94.
Dr. Samuel M. Meier M. Sc. Dominique Kreutz Dr. Lilli Winter M. Sc. Matthias H. M. Klose M. Sc. Klaudia Cseh M. Sc. Tamara Weiss Dr. Andrea Bileck M. Sc. Beatrix Alte Dr. Johanna C. Mader M. Sc. Samir Jana Dr. Annesha Chatterjee Dr. Arindam Bhattacharyya Michaela Hejl Dr. Michael A. Jakupec Priv.-Doz. Dr. Petra Heffeter Prof. Dr. Walter Berger Prof. Dr. Christian G. Hartinger Prof. Dr. Bernhard K. Keppler Prof. Dr. Gerhard Wiche Prof. Dr. Christopher Gerner 《Angewandte Chemie (International ed. in English)》2017,56(28):8267-8271
Organometallic metal(arene) anticancer agents require ligand exchange for their anticancer activity and this is generally believed to confer low selectivity for potential cellular targets. However, using an integrated proteomics-based target-response profiling approach as a potent hypothesis-generating procedure, we found an unexpected target selectivity of a ruthenium(arene) pyridinecarbothioamide (plecstatin) for plectin, a scaffold protein and cytolinker, which was validated in a plectin knock-out model in vitro. Plectin targeting shows potential as a strategy to inhibit tumor invasiveness as shown in cultured tumor spheroids while oral administration of plecstatin-1 to mice reduces tumor growth more efficiently in the invasive B16 melanoma than in the CT26 colon tumor model. 相似文献
95.
Summary The development of a compressible boundary layer over a wedge impulsively set into motion is studied in this paper. The initial motion is independent of the leading edge effect and the solutions are those of a Rayleigh-type problem. The motion tends to an ultimate steady state of Falkner-Skan type. The equations governing the transient boundary layer from the initial steady state to the terminal steady-state change their character after certain time due to the leading edge effect and thereafter solution depends on both the end conditions. Numerical solutions are obtained through the second-order accuracy upwind scheme. The effects of the Falkner-Skan parameter and the surface temperature on the transient flow and heat transfer are also studied. It has been found that the flow separation does not occur form–0.0707 when
w
= 1.5 (hot wall), andm–0.118 when
0.5
(cold wall). 相似文献
96.
Sharvari Deshmukh Kalyani Kamde Arun Jana Sanjivani Korde Rajib Bandyopadhyay Ravi Sankar Nabarun Bhattacharyya R.A. Pandey 《Analytica chimica acta》2014
Electronic nose systems when deployed in network mesh can effectively provide a low budget and onsite solution for the industrial obnoxious gaseous measurement. For accurate and identical prediction capability by all the electronic nose systems, a reliable calibration transfer model needs to be implemented in order to overcome the inherent sensor array variability. In this work, robust regression (RR) is used for calibration transfer between two electronic nose systems using a Box–Behnken (BB) design. Out of the two electronic nose systems, one was trained using industrial gas samples by four artificial neural network models, for the measurement of obnoxious odours emitted from pulp and paper industries. The emissions constitute mainly of hydrogen sulphide (H2S), methyl mercaptan (MM), dimethyl sulphide (DMS) and dimethyl disulphide (DMDS) in different proportions. A Box–Behnken design consisting of 27 experiment sets based on synthetic gas combinations of H2S, MM, DMS and DMDS, were conducted for calibration transfer between two identical electronic nose systems. Identical sensors on both the systems were mapped and the prediction models developed using ANN were then transferred to the second system using BB–RR methodology. The results showed successful transmission of prediction models developed for one system to other system, with the mean absolute error between the actual and predicted concentration of analytes in mg L−1 after calibration transfer (on second system) being 0.076, 0.1801, 0.0329, 0.427 for DMS, DMDS, MM, H2S respectively. 相似文献
97.
In this paper, we first consider the problem of determining the robust positivity of a real function f(x) as the real vector x varies over a box X∈Rl. We show that, it is sufficient to check a finite number of specially constructed points. This is accomplished by using some results on sign-definite decomposition. We then apply this result to determine the robust Hurwitz stability of a family of complex polynomials whose coefficients are polynomial functions of the parameters of interest. We develop an eight polynomial vertex stability test that is a sufficient condition of Hurwitz stability of the family. This test reduces to Kharitonov’s well known result for the special case where the parameters are just the polynomial coefficients. In this case, the result is tight. This test can be recursively and modularly used to construct an approximation of arbitrary accuracy to the actual stabilizing set. The result is illustrated by examples. 相似文献
98.
Bhattacharyya S Gonzalez M Robertson JD Bhattacharya R Mukherjee P 《Chemical communications (Cambridge, England)》2011,47(30):8530-8532
A simple synthesis of a targeted drug delivery system with enhanced cytotoxicity to (epidermal growth factor receptor) EGFR(+) cancer cells. 相似文献
99.
Yeh YC Patra D Yan B Saha K Miranda OR Kim CK Rotello VM 《Chemical communications (Cambridge, England)》2011,47(11):3069-3071
A new class of quaternary ammonium derivatives has been used to synthesize cationic CdSe/ZnS quantum dots with exceptional stability in water as well as in biological media. 相似文献
100.
Electric-field induced elastic stretching of multiwalled carbon nanotube clusters: a realistic model
Bhattacharyya SS Yang GH Tie W Lee YH Lee SH 《Physical chemistry chemical physics : PCCP》2011,13(45):20435-20440
The oscillating electric-field induced stretching phenomenon of multiwalled carbon nanotube (MWCNT) clusters in liquid crystal medium demonstrates distinct threshold behaviour under optical microscopic investigation. The optimum field required for the initiation of MWCNT cluster stretching is found to depend on their length in the field-off state. The phenomenon has been explained in light of a classical theoretical model assuming MWCNT agglomerates as a single electric dipole. The spring constant and induced charge obtained by fitting the formulated theoretical model show good agreement with previous reports, hence establish the proposed dipolar reorientation mechanism of MWCNT clusters induced by the electric field. 相似文献