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121.
Abazov VM Abbott B Abdesselam A Abolins M Abramov V Acharya BS Adams DL Adams M Ahmed SN Alexeev GD Alves GA Amos N Anderson EW Baarmand MM Babintsev VV Babukhadia L Bacon TC Baden A Baldin B Balm PW Banerjee S Barberis E Baringer P Barreto J Bartlett JF Bassler U Bauer D Bean A Begel M Belyaev A Beri SB Bernardi G Bertram I Besson A Beuselinck R Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Blazey G Blessing S Boehnlein A Bojko NI Borcherding F Bos K Brandt A Breedon R Briskin G Brock R 《Physical review letters》2001,87(6):061802
We present results of searches for technirho (rho(T)), techniomega (omega(T)), and Z' particles, using the decay channels rho(T),omega(T),Z'-->e(+)e(-). The search is based on 124.8 pb(-1) of data collected by the D0 detector at the Fermilab Tevatron during 1992-1996. In the absence of a signal, we set 95% C.L. upper limits on the cross sections for the processes pp-->rho(T),omega(T),Z'-->e(+)e(-) as a function of the mass of the decaying particle. For certain model parameters, we exclude the existence of degenerate rho(T) and omega(T) states with masses below about 200 GeV. We exclude a Z' with mass below 670 GeV, assuming that it has the same couplings to fermions as the Z boson. 相似文献
122.
Aitala EM Amato S Anjos JC Appel JA Ashery D Banerjee S Bediaga I Blaylock G Bracker SB Burchat PR Burnstein RA Carter T Carvalho HS Copty NK Cremaldi LM Darling C Denisenko K Devmal S Fernandez A Fox GF Gagnon P Gobel C Gounder K Halling AM Herrera G Hurvits G James C Kasper PA Kwan S Langs DC Leslie J Lundberg B Magnin J Massafferri A MayTal-Beck S Meadows B de Mello Neto JR Mihalcea D Milburn RH de Miranda JM Napier A Nguyen A d'Oliveira AB O'Shaughnessy K Peng KC Perera LP Purohit MV 《Physical review letters》2001,86(5):770-774
From a sample of 1172 +/- 61 D(+)-->pi(-)pi(+)pi(+) decays, we find gamma(D(+)-->pi(-)pi(+)pi(+))/gamma(D(+)-->K-pi(+)pi(+)) = 0.0311 +/- 0.0018(+0.0016)(-0.0026). Using a coherent amplitude analysis to fit the Dalitz plot of these decays, we find strong evidence that a scalar resonance of mass 478(+24)(-23) +/- 17 MeV/c(2) and width 324(+42)(-40) +/- 21 MeV/c(2) accounts for approximately half of all decays. 相似文献
123.
Banerjee P.P. Avila R. He D. Shenliang Wu Bechhoefer E. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2007,37(6):1318-1326
In this paper, a novel discriminant analysis based predictive model for preventing false alarms leading to unnecessary replacement of an avionic system component is presented. The model is validated by prediction of false alarms (also known as false positives, type I, or alpha errors) in the left generator shaft of a Sikorsky helicopter UH-60, using the Goodrich health and usage management system (HUMS). The paper presents one of the first approaches based on applying discriminant analysis for prognostics of avionic systems, specifically in the context of identifying false positives within the next 1 or 2 h. In practice, predictions for the next 2 h are sufficient as typical helicopter flight schedules and durations are such that up to 2 h advance notice is most useful. This is an important contribution because drive train components of helicopters are normally very robust with very rare failures; therefore, the cost of unnecessary preventive maintenance based on false alarms is very high. 相似文献
124.
Mallick S. Banerjee K. Ghosh S. Rodriguez J.B. Krishna S. 《Photonics Technology Letters, IEEE》2007,19(22):1843-1845
InAs-GaSb strain layer superlattice p+-n--n avalanche photodiodes (APDs) are fabricated using a newly introduced electron-beam aided zinc sulfide deposition. Temperature-dependent measurements were performed on 300 times 300 mum2 mesa etched APDs. The effect of passivation was also studied on the diode characteristics and APD performances. Temperature-dependent gain strongly correlates with avalanche mechanism. 相似文献
125.
Sachin Joshi Sagnik Dey Michelle Chaumont Alan Campion Sanjay K. Banerjee 《Journal of Electronic Materials》2007,36(6):641-647
We demonstrate ultra-thin (<150 nm) Si1−x
Ge
x
dislocation blocking layers on Si substrates used for the fabrication of tensile-strained Si N channel metal oxide semiconductor
(NMOS) and Ge P channel metal oxide semiconductor (PMOS) devices. These layers were grown using ultra high vacuum chemical
vapor deposition (UHVCVD). The Ge mole fraction was varied in rapid, but distinct steps during the epitaxial layer growth.
This results in several Si1−x
Ge
x
interfaces in the epitaxially grown material with significant strain fields at these interfaces. The strain fields enable
a dislocation blocking mechanism at the Si1−x
Ge
x
interfaces on which we were able to deposit very smooth, atomically flat, tensile-strained Si and relaxed Ge layers for the
fabrication of high mobility N and P channel metal oxide semiconductor (MOS) devices, respectively. Both N and P channel metal
oxide semiconductor field effect transister (MOSFETs) were successfully fabricated using high-k dielectric and metal gates
on these layers, demonstrating that this technique of using ultra-thin dislocation blocking layers might be ideal for incorporating
high mobility channel materials in a conventional CMOS process. 相似文献
126.
In certain species of moths and butterflies iridescent colors arise from subwavelength diffractive surface corrugation of
the wing-scales. The optical properties of such structures depend strongly on wavelength, incidence angle, and state of polarization
of illuminating radiation, and the viewing angle. In this paper, we study the reflection spectra of the wings of the Morpho didius butterfly by simulating a double-layered model of a transverse cross-section comprised of the ground scale and the cover
scale. Each layer contains a certain quasi-periodic arrangement of tree-like subwavelength microstructures. The simulation
is done using a high accuracy nonstandard finite-difference time-domain (FDTD) method in two dimensions. We assume that the
structure is made of a slightly lossy dielectric material. The wavelength dependence of the complex refractive index for the
ground scale of Morpho didius is assumed to be similar to that of Morpho sulkowskyi. The complex refractive index in the latter case was obtained by comparing the computed reflection/transmission spectra with
corresponding experimental measurements at normal incidence. 相似文献
127.
S. Banerjee B. White L. Huang B.J. Rego S. O’Brien I.P. Herman 《Applied Physics A: Materials Science & Processing》2007,86(4):415-419
Single-walled carbon nanotubes (SWNTs) have been precisely aligned and positioned in device architectures using ac dielectrophoresis
by patterning floating metal posts or strips within the electrode gaps. These structures perturb the electric field, causing
local enhancements in the field intensity, as seen in simulation, that guide the nanotubes along a predictable path in given
directions, in zigzag patterns, or as single or a sequence of tubes along a series of posts. This method enables the assembly
of SWNTs in complex multi-electrode geometries, when specifying the electrode voltages is not sufficient to direct the desired
assembly. The device characteristics of the dielectrophoretically-aligned SWNTs are discussed.
PACS 61.46.Fg; 73.63.-b; 87.15.Tt 相似文献
128.
A modified combustion process, namely a mixed fuel process making use of a mixture of two fuels, such as citric acid and glycine
has been developed to prepare nanocrystalline ceria powders. The effect of the mixed fuel and the different fuel to oxidant
ratios on the decomposition characteristics of the gels were investigated by simultaneous thermal analysis experiments. It
was established from various characterization techniques that the ceria powder prepared through the mixed fuel process has
got the optimum powder characteristics, namely, a surface area of 33.33 m2/g and a crystallite size of 14 nm compared to the powders produced through the combustion process using a single fuel like
glycine or citric acid. Such powders when sintered at 1250°C resulted in pellets with densities in the range of 94–96% of
theoretical density. In this paper, we have carried out systematic studies on the sintering of ceria powders prepared by different
approaches. The sintered ceramic from mixed fuel batch, exhibited and retained relative density more than 95% up to 1250°C
and this data clearly underscores the ability of this process in developing ceria ceramics with increased stability against
reduction. 相似文献
129.
A new palladium catalyzed protocol for an atom-efficient cross-coupling reaction of triarylbismuths with aryl halides and triflates has been described. The palladium catalytic system with Cs2CO3 base was found to be very efficient in DMA solvent to furnish excellent yields of cross-coupled functionalized biaryls in short reaction times. 相似文献
130.
Manish K. Jaiswal Shailee Mehta Rinti Banerjee D. Bahadur 《Colloid and polymer science》2012,290(7):607-617
A comparative study of thermoresponsive poly(N-isopropylacrylamide)(PNIPAAm)-chitosan (CS)-based magnetic nanohydrogels (MNHGs) encapsulating functionalized Fe3O4 nanoparticles (NPs) in terms of the parameters governing their suitability for real hyperthermia is reported. Iron oxide
NPs functionalized with (a) citric acid (CA-Fe3O4), (b) ethylenediamine (Amine-Fe3O4) and (c) dimercaptosuccininc (DMSA-Fe3O4) have been synthesized and their encapsulation into MNHGs was obtained through physical encapsulation method. The structural
characterizations of synthesized materials include X-ray diffraction, FT-IR, TGA, ICP-AES and X-ray photoelectron spectroscopy
(XPS). Encapsulation of the functionalized NPs into MNHGs were observed in TEM micrographs, while SEM and AFM micrographs
confirmed their spherical morphology (~250–300 nm). Lower critical solution temperature (LCST) variation was measured by UV–visible
spectrophotometer and differential scanning calorimetry (DSC). MNHGs exhibited sufficient magnetization and heating ability
for hyperthermia. Typically, hydrogels containing CA-Fe3O4 (50 mg/ml) raised the temperature of the medium to 43 °C, a suitable dose for in vivo application in tumor-bearing mice. 相似文献