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191.
Nakhjavan B Tahir MN Panthöfer M Gao H Gasi T Ksenofontov V Branscheid R Weber S Kolb U Schreiber LM Tremel W 《Chemical communications (Cambridge, England)》2011,47(31):8898-8900
A wet chemical approach from organometallic reactants allowed the targeted synthesis of Co@Fe(2)O(3) heterodimer and CoFe(2)O(4) ferrite nanoparticles. They display magnetic properties that are useful for magnetic MRI detection. 相似文献
192.
Berry DJ Ma Y Ballinger JR Tavaré R Koers A Sunassee K Zhou T Nawaz S Mullen GE Hider RC Blower PJ 《Chemical communications (Cambridge, England)》2011,47(25):7068-7070
A new tripodal tris(hydroxypyridinone) bifunctional chelator for gallium allows easy production of (68)Ga-labelled proteins rapidly under mild conditions in high yields at exceptionally high specific activity and low concentration. 相似文献
193.
Jaffer SS Ghosh P Purkayastha P 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,78(5):1587-1591
trans-2-[4-(Dimethylamino)styryl]benzothiazole (DMASBT) is known to have dual emitting states where the locally excited (LE) state is responsible for fluorescence in less polar environment and in polar milieu fluorescence is from the twisted intramolecular charge transfer (TICT) state. This compound also undergoes minor groove binding to herring sperm DNA (hsDNA) evidenced by the absorption spectra before and after the binding process and an effect on DMASBT fluorescence by an anionic quencher. The binding occurs efficiently in a 1:1 manner, i.e. one guest molecule binds to one site on the hsDNA. Instead of following the DNA twist, the aromatic part seems to project outward. Thus, the bound molecule can be successfully extracted out from the DNA in a controlled way by the hydrophobic cavity of α-cyclodextrin (α-CD). The extraction starts even with a low concentration of α-CD and increases as the concentration is increased. Absorption, steady-state and time resolved fluorescence spectroscopic methods have been employed to explore the mechanistic pathway of binding of DMASBT to hsDNA. The mechanistic approach toward controlled extraction of the guest molecules from hsDNA by α-CD is reported and is expected to serve a significant purpose in treatment of drug overdose. 相似文献
194.
Malek SN Lee GS Hong SL Yaacob H Wahab NA Faizal Weber JF Shah SA 《Molecules (Basel, Switzerland)》2011,16(6):4539-4548
Investigations on the cytotoxic effects of the crude methanol and fractionated extracts (hexane, ethyl acetate) C. mangga against six human cancer cell lines, namely the hormone-dependent breast cell line (MCF-7), nasopharyngeal epidermoid cell line (KB), lung cell line (A549), cervical cell line (Ca Ski), colon cell lines (HCT 116 and HT-29), and one non-cancer human fibroblast cell line (MRC-5) were conducted using an in-vitro neutral red cytotoxicity assay. The crude methanol and fractionated extracts (hexane and ethyl acetate) displayed good cytotoxic effects against MCF-7, KB, A549, Ca Ski and HT-29 cell lines, but exerted no damage on the MRC-5 line. Chemical investigation from the hexane and ethyl acetate fractions resulted in the isolation of seven pure compounds, namely (E)-labda-8(17),12-dien-15,16-dial (1), (E)-15,16-bisnor-labda-8(17),11-dien-13-on (2), zerumin A (3), β-sitosterol, curcumin, demethoxycurcumin and bis-demethoxycurcumin. Compounds 1 and 3 exhibited high cytotoxic effects against all six selected cancer cell lines, while compounds 2 showed no anti-proliferative activity on the tested cell lines. Compound 1 also demonstrated strong cytotoxicity against the normal cell line MRC-5. This paper reports for the first time the cytotoxic activities of C. mangga extracts on KB, A549, Ca Ski, HT-29 and MRC-5, and the occurrence of compound 2 and 3 in C. mangga. 相似文献
195.
Javed Iqbal Feroza Hamid Wattoo Muhammad Hamid Sarwar Wattoo Rukhsana Malik Syed Ahmad Tirmizi Muhammad Imran Allah Bux Ghangro 《Arabian Journal of Chemistry》2011,4(4):389-395
Chitosan flakes, extracted from prawns and labeo rohita scales, with high adsorption capacity were prepared after chemical treatment and were used to remove acid yellow dye from water. The results showed that adsorption capacity is dependent on pH, initial concentration of dye, BET, Langmuir surface area and pore volume of the adsorbent. In acidic conditions, the polymer amino groups were protonated (positively charged polymer chain), which showed attraction with negative ions of anionic dye. Chitosan from prawns scales showed higher dye adsorption under the same experimental conditions. Adsorption isotherms were developed and equilibrium data fitted well to Langmuir and Freundlich isotherm models. 相似文献
196.
Shahid Hussain Arshad Muhammad Nawaz Naeem Nazra Sultana Zafar Iqbal Abdul Ghafar Shah 《Archive of Applied Mechanics (Ingenieur Archiv)》2011,81(8):999-1016
In the present work, vibration characteristics of thin functionally graded cylindrical shells are studied under the influence
of various boundary conditions. Fabrication of FGM cylindrical shell is carried out by using exponential volume fraction law.
Strain- and curvature-displacements relationships are taken from Love’s thin shell theory. The frequency equation in the form
of eigenvalue problem is obtained by adapting the Rayleigh-Ritz method. Characteristic beam functions are assumed to approximate
the axial modal dependence. Effects of exponential volume fraction law on the natural frequencies of the FGM cylindrical shells
for various boundary conditions are studied against circumferential wave number, length to radius ratio and thickness to radius
ratio for different values of power law exponents. Results evaluated show good agreement with those available in the literature. 相似文献
197.
Santanu Chakraborty D. Bhattacharjee Syed Arshad Hussain 《Applied Physics A: Materials Science & Processing》2013,111(4):1037-1043
In the present communication, we report the formation of organized nanoscale aggregates of a coumarin derivative 7 Hydroxy-N-Octadecyl Coumarin-3-Carboxamide (7HNO3C) at the air–water interface and in Langmuir–Blodgett (LB) films in the presence and absence of stearic acid (SA). A pressure-area isotherm reveals that the 7HNO3C form stable monolayer at the air–water interface. However, the stability can be improved by mixing it with a fatty acid stearic acid (SA). The miscibility study shows that the nature of interaction is strongly dependent on the mixing ratio and surface pressure. At a mole fraction of 0.4 of 7HNO3C in SA, the attractive and repulsive interaction between these two molecules balance each other forming a stable film with nanoscale aggregates. UV-Vis absorption spectroscopic studies reveal the nature of the aggregates in LB films. Scanning electron microscopy gives compelling visual evidence of formation of nanoscale aggregates in the mixed LB films. 相似文献
198.
Chandra Sekhar A. Durisety Rajagopal Vijayraghavan Lakshmipriya Seshan Syed K. Islam Benjamin J. Blalock 《Analog Integrated Circuits and Signal Processing》2006,48(2):143-150
This paper demonstrates a technique for controlling the electron emission of an array of field emitting vertically aligned
carbon nanofibers (VACNFs). An array of carbon nanofibers (CNF) is to be used as the source of electron beams for lithography
purposes. This tool is intended to replace the mask in the conventional photolithography process by controlling their charge
emission using the “Dose Control Circuitry” (DCC). The large variation in the charge emitted between CNFs grown in identical
conditions forced the controller design to be based on fixed dose rather than on fixed time. Compact digital control logic
has been designed for controlling the operation of DCC. This system has been implemented in a 0.5 μm CMOS process.
Chandra Sekhar A. Durisety received his B.E. (Hons.) Instrumentation from Birla Institute of Technology and Sciences, Pilani, India in 1997 and his
M.S in Electrical Engineering from University of Tennessee, Knoxville in 2002. Since 2003, he has been working towards his
Ph.D degree also in Electrical Engineering at Integrated Circuits and Systems Lab (ICASL), University of Tennessee, Knoxville.
He joined Wipro Infotech Ltd, Global R & D, Bangalore, India in 1997, where he designed FPGA based IPs for network routers.
Since 1999, he was involved in the PCI bridge implementation at CMOS chips Inc, Santa Clara, CA, and the test bench development
for Sony’s MP3 player, while at Toshiba America Electronic Components Inc., San Jose, CA. His research interests include multi-stage
amplifiers, data converters, circuits in SOI and Floating Gate Devices.
Rajagopal Vijayaraghavan received the B.E degree in electronics and communication engineering from Madras University in 1998 and the M.S degree in
electrical engineering from the University of Texas, Dallas in 2001.He is currently working towards the Ph.D degree in electrical
engineering at the University of Tennessee. His research interest is in the area of CMOS Analog and RF IC design. His current
research focuses on LNAs and VCOs using SOI based MESFET devices.
Lakshmipriya Seshan was born in Trivandrum, India on April 30, 1979. She received her B.tech in Electronincs & Communication Engg from Kerala
University, India in June 2000 and M.S in Electrical Engg from University of Tennessee in 2004. In 2004, she joined Intel
Corporation as an Analog Engineer, where she is engaged in the design of low power, high speed analog circuits for various
I/O interface topologies.
Syed K. Islam received his B.Sc. in Electrical and Electronic Engineering from Bangladesh University of Engineering and Technology (BUET)
and M.S. and Ph.D. in Electrical and Systems Engineering from the University of Connecticut. He is presently an Associate
Professor in the Department of Electrical and Computer Engineering at the University of Tennessee, Knoxville. Dr. Islam is
leading the research efforts of the Analog VLSI and Devices Laboratory at the University of Tennessee. His research interests
are design, modeling and fabrication of microelectronic/optoelectronic devices, molecular scale electronics and nanotechnology,
biomicroelectronics and monolithic sensors. Dr. Islam has numerous publications in technical journals and conference proceedings
in the areas of semiconductors devices and circuits.
Benjamin J. Blalock received his B.S. degree in electrical engineering from The University of Tennessee, Knoxville, in 1991 and the M.S. and
Ph.D. degrees, also in electrical engineering, from the Georgia Institute of Technology, Atlanta, in 1993 and 1996 respectively.
He is currently an Assistant Professor in the Department of Electrical and Computer Engineering at The University of Tennessee
where he directs the Integrated Circuits and Systems Laboratory (ICASL). His research focus there includes analog IC design
for extreme environments (both wide temperature and radiation immune), multi-gate transistors and circuits on SOI, body-driven
circuit techniques for ultra low-voltage analog, mixed-signal/mixed-voltage circuit design for systems-on-a-chip, and bio-microelectronics.
Dr. Blalock has co-authored over 60 published refereed papers. He has also worked as an analog IC design consultant for Cypress
Semiconductor Corp. and Concorde Microsystems Inc. 相似文献
199.
Saqib Ali Syed Usman Ahmad Saira Shahzadi Sadiq‐ur‐Rehman Masood Parvez Muhammad Mazhar 《应用有机金属化学》2005,19(1):201-201
Me2Sn(S2CN(CH2)5)Cl contains five‐coordinated tin with a bidentate dithiocarbamate ligand spanning equatorial and axial positions in a distorted trigonal bipyramidal geometry. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
200.
Disposal of untreated industrial effluents is drastically deteriorating the quality of underground water. Research work has been conducted to analyze the effect of disposal of urea plant effluent on the quality of ground water of the District Mianwali Daudkhail, Pakistan. For this purpose the effluent and ground water samples were analyzed for pH, TDS, TSS, Cl, F, COD, BOD, Fe, Zn, Pb, Cu, Cr, Cd, Mn, and As. Results obtained were compared with WHO and NEQS standards for drinking and effluent emission limits, respectively. Moreover, effluent samples were also evaluated for irrigation purposes and results compared with criteria recommended for irrigation water. Results showed though the effluents were according to the standards given by National Environmental Quality Standards (NEQS) for liquid emission and fit for irrigation purposes, the quality of underground water was below standard due to having a higher quantity of total dissolved solids than permissible. 相似文献