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551.
Tanihata I Alcorta M Bandyopadhyay D Bieri R Buchmann L Davids B Galinski N Howell D Mills W Mythili S Openshaw R Padilla-Rodal E Ruprecht G Sheffer G Shotter AC Trinczek M Walden P Savajols H Roger T Caamano M Mittig W Roussel-Chomaz P Kanungo R Gallant A Notani M Savard G Thompson IJ 《Physical review letters》2008,100(19):192502
The p((11)Li, (9)Li)t reaction has been studied for the first time at an incident energy of 3A MeV at the new ISAC-2 facility at TRIUMF. An active target detector MAYA, built at GANIL, was used for the measurement. The differential cross sections have been determined for transitions to the (9)Li ground and first excited states in a wide range of scattering angles. Multistep transfer calculations using different (11)Li model wave functions show that wave functions with strong correlations between the halo neutrons are the most successful in reproducing the observation. 相似文献
552.
García Saiz E Gregori G Khattak FY Kohanoff J Sahoo S Naz GS Bandyopadhyay S Notley M Weber RL Riley D 《Physical review letters》2008,101(7):075003
We have investigated the angular variation in elastic x-ray scattering from a dense, laser-shock-compressed aluminum foil. A comparison of the experiment with simulations using an embedded atom potential in a molecular dynamics simulation shows a significantly better agreement than simulations based on an unscreened one-component plasma model. These data illustrate, experimentally, the importance of screening for the dense plasma static structure factor. 相似文献
553.
Venkataramanan M Skanth G Bandyopadhyay K Vijayamohanan K Pradeep T 《Journal of colloid and interface science》1999,212(2):553-561
Self-assembled monolayers of diphenyldisufide (DDS), naphthalenedisulfide (NDS), and diphenyldiselenide (DDSe) on polycrystalline silver films have been investigated by surface enhanced Raman spectroscopy (SERS) and X-ray photoelectron spectroscopy (XPS). DDS adsorbs on Ag through a homolytic cleavage of the S-S bond and resultant thiolate at the surface decomposes upon prolonged exposure to air. The geometry of the molecule is such that the benzene ring is almost horizontal to the surface. The Raman spectrum has been assigned in the light of ab-initio molecular orbital calculations. In DDSe, the Se-Se bond is retained upon adsorption and the molecule sticks up. In contrast, NDS is highly reactive on the microscopically rough surface so that a stable monolayer could not be prepared. A temperature dependent Raman study of the DDS monolayer shows the absence of any reorientation at the surface as one would expect from the adsorption geometry. XPS study complements the SERS data and shows the presence of Ag2S on an NDS exposed surface. Copyright 1999 Academic Press. 相似文献
554.
Akash Bandyopadhyay 《International Journal of Theoretical Physics》1999,38(5):1531-1537
The weakest set of necessary and sufficientconditions for the existence of a conserved tracelesssymmetric stress-energy tensor for a scale-invariantPoincare field theory over a d-dimensional flatspace-time manifold has been proved. This improved tensoris explicitly constructed for arbitrary space-timedimensions including d = 2. The example of a vectorfield in d 3, d 4 demonstrates that fullconformal symmetry over a flat space-time is sufficientbut not necessary for the existence of an improvedtensor. 相似文献
555.
Sudip?Biswas Susmita?Pradhan Hemanta?Naskar Rajib?Bandyopadhyay Panchanan?PramanikEmail author 《Mikrochimica acta》2018,185(11):513
Titanium dioxide nanoparticles (NPs) were synthesized by a sol-gel method from hexafluorotitanic acid using poly(ethylene glycol) as a capping agent. The crystal structure and morphology of the NPs were characterized by X-ray diffraction, FESEM, and TEM. The NPs were used to modify a graphite paste electrode for simultaneous determination of uric acid (UA) and guanine (GU). The effect of calcination temperature on crystal structure and electrocatalytic activity was investigated. The electrochemical responses to UA and GU at bare GP, TiO2–350/GP, and TiO2–600/GP electrodes were compared. The DPV oxidation peaks of UA and GU were found to be strongest at around 304 and 673 mV, respectively, against Ag/AgCl reference electrode, and this are well separated for effective simultaneous determination. UA and GU can be simultaneously determined by this method. Response is linear within the range 0.1–500 μM and 0.1–40 μM for UA and GU, respectively. The detection limits are 70 nM for UA and 50 nM for GU (at an S/N? ratio of?3). The TiO2–600/GP electrode showed excellent analytical performance when analyzing spiked urine and serum samples. 相似文献
556.
In this study, a solvothermal method was used to synthesize anatase titanium dioxide (TiO2) nanoparticles in the presence of oleic acid (OA) and oleylamine (OM) as morphology‐directing agents. Functional nanocomposite fibers of poly(ethylene terephtalate) (PET) containing surfactants‐capped TiO2 nanoparticles were developed by electrospinning technique. The morphology, thermal stability and mechanical properties of PET/TiO2 nanocomposite mats were investigated as a function of TiO2 concentration. Morphology investigation showed interesting results in terms of the level of TiO2 dispersion inside the fibers and the improvement of the quality (smoothness) of the fibers' surface when the synthesized nanorhombic TiO2 nanoparticles were used compared to a commercial P25 TiO2 (AEROXIDE P25). The presence of OA and OM on the surface of the nanorhombic synthesized TiO2 led to a significant improvement of TiO2 dispersion inside the PET matrix. Furthermore, the physical interaction between the PET matrix and TiO2 nanoparticles resulted in an enhanced thermal stability, and an increase of the Young's modulus and tensile strength for TiO2 concentration up to 10 wt%. 相似文献
557.
Racemic and scalemic PTC-protected alpha-hydroxystannanes cross-couple with alkenyl/aryl/heteroaryl iodides in moderate to good yields using copper(I) thiophene-2-carboxylate (CuTC) in THF at or below room temperature. Simple aryl iodides and 1-iodocyclohexene, two classes of electrophiles that typically react sluggishly, are also good substrates. Cross-couplings proceed with retention of configuration at the alkenyl- and stannyl-substituted stereocenters. 相似文献
558.
Quality of decisions in inventory management models depends on the accuracy of parameter estimates used for decision making. In many situations, error in decision making is unavoidable. In such cases, sensitivity analysis is necessary for better implementation of the model. Though the newsvendor model is one of the most researched inventory models, little is known about its robustness. In this paper, we perform sensitivity analysis of the classical newsvendor model. Conditions for symmetry/skewness of cost deviation (i.e., deviation of expected demand–supply mismatch cost from its minimum) have been identified. These conditions are closely linked with symmetry/skewness of the demand density function. A lower bound of cost deviation is established for symmetric unimodal demand distributions. Based on demonstrations of the lower bound, we found the newsvendor model to be sensitive to sub-optimal ordering decisions, more sensitive than the economic order quantity model. Order quantity deviation (i.e., deviation of order quantity from its optimum) is explored briefly. We found the magnitude of order quantity deviation to be comparable with that of parameter estimation error. Mean demand is identified as the most influential parameter in deciding order quantity deviation. 相似文献
559.
We calculate the Wigner quasiprobability distribution function of the quantum elliptical vortex in elliptical beam (EEV), produced by coupling squeezed coherent states of two modes. The coupling between the two modes is performed by using beam splitter (BS) or a dual channel directional coupler (DCDC). The quantum interference due to the coupling between the two modes promises the generation of controlled entanglement for quantum computation and quantum tomography. 相似文献
560.
Finlay P Ettenauer S Ball GC Leslie JR Svensson CE Andreoiu C Austin RA Bandyopadhyay D Cross DS Demand G Djongolov M Garrett PE Green KL Grinyer GF Hackman G Leach KG Pearson CJ Phillips AA Sumithrarachchi CS Triambak S Williams SJ 《Physical review letters》2011,106(3):032501
A high-precision half-life measurement for the superallowed β+ emitter 26Al(m) was performed at the TRIUMF-ISAC radioactive ion beam facility yielding T 1/2 6346.54 ± 0.46(stat) ± 0.60 (syst) ms, consistent with, but 2.5 times more precise than, the previous world average. The 26Al(m) half-life and ft value, 3037.53(61) s, are now the most precisely determined for any superallowed β decay. Combined with recent theoretical corrections for isospin-symmetry-breaking and radiative effects, the corrected Ft value for (26)Al(m), 3073.0(12) s, sets a new benchmark for the high-precision superallowed Fermi β-decay studies used to test the conserved vector current hypothesis and determine the V(ud) element of the Cabibbo-Kobayashi-Maskawa quark mixing matrix. 相似文献