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61.
This paper addresses the problem of scheduling cascaded ‘blocked out’ continuous processing units separated by finite capacity
storage tanks. The raw materials for the product lines arrive simultaneously on the input side of the first unit. But every
unit can process only one product line at a time, thus giving rise to the possibility of spillage of raw material due to limited
storage capacity. The need to process multiple product lines and the added constraint of multiple intermediate upliftment
dates aggravate the problem. This problem is quite common in petrochemical industry. The paper provides a MINLP (Mixed Integer
Non-Linear Programming) formulation of the problem. However, for any realistic scheduling horizon, the size of the problem
is too large to be solved by standard packages. We have proposed a depth first branch and bound algorithm, guided by heuristics,
to help planners in tackling the problem. The suggested algorithm could output near optimal solutions for scheduling horizons
of 30 time periods when applied to real life situations involving 3 units and 3 product lines.
Preliminary version of the paper appeared in the proceedings of MISTA, 2005. 相似文献
62.
63.
64.
The total synthesis of oxacalothrixins, an isostere of biologically important carbazoloquinone alkaloid, calothrixin B was achieved from 2-acetyl-3-methylbenzofuran. An iodine/TBHP-mediated oxidative cyclization of benzofuranyl-enamine has been employed as a key step to synthesize, the crucial intermediate 1-hydroxy dibenzofurancarbaldehyde. The latter upon reductive cyclization followed by PIDA-mediated oxidation furnished oxacalothrixin B and its analogues. 相似文献
65.
Abazov VM Abbott B Acharya BS Adams M Adams T Alexeev GD Alkhazov G Alton A Alverson G Alves GA Aoki M Arov M Askew A Asman B Atramentov O Avila C Backusmayes J Badaud F Bagby L Baldin B Bandurin DV Banerjee S Barberis E Baringer P Barreto J Bartlett JF Bassler U Bazterra V Beale S Bean A Begalli M Begel M Belanger-Champagne C Bellantoni L Beri SB Bernardi G Bernhard R Bertram I Besançon M Beuselinck R Bezzubov VA Bhat PC Bhatnagar V Blazey G Blessing S Bloom K Boehnlein A Boline D Boos EE 《Physical review letters》2011,107(1):011804
We present a study of the dijet invariant mass spectrum in events with two jets produced in association with a W boson in data corresponding to an integrated luminosity of 4.3 fb(-1) collected with the D0 detector at √s = 1.96 TeV. We find no evidence for anomalous resonant dijet production and derive upper limits on the production cross section of an anomalous dijet resonance recently reported by the CDF Collaboration, investigating the range of dijet invariant mass from 110 to 170 GeV/c(2). The probability of the D0 data being consistent with the presence of a dijet resonance with 4 pb production cross section at 145 GeV/c(2) is 8×10(-6). 相似文献
66.
Abazov VM Abbott B Acharya BS Adams M Adams T Alexeev GD Alkhazov G Alton A Alverson G Alves GA Ancu LS Aoki M Arnoud Y Arov M Askew A Asman B Atramentov O Avila C Backusmayes J Badaud F Bagby L Baldin B Bandurin DV Banerjee S Barberis E Baringer P Barreto J Bartlett JF Bassler U Bazterra V Beale S Bean A Begalli M Begel M Belanger-Champagne C Bellantoni L Beri SB Bernardi G Bernhard R Bertram I Besançon M Beuselinck R Bezzubov VA Bhat PC Bhatnagar V Blazey G Blessing S Bloom K Boehnlein A 《Physical review letters》2011,107(1):011801
We search for resonant WW or WZ production by using up to 5.4 fb(-1) of integrated luminosity collected by the D0 experiment in run II of the Fermilab Tevatron Collider. The data are consistent with the standard model background expectation, and we set limits on a resonance mass by using the sequential standard model W' boson and the Randall-Sundrum model graviton G as benchmarks. We exclude a sequential standard model W' boson in the mass range 180-690 GeV and a Randall-Sundrum graviton in the range 300-754 GeV at 95% C.L. 相似文献
67.
We present simple and accurate analytical expressions for transmission coefficient at the splice with angular offset and transverse offset in case of first higher mode propagation in graded index fibers. We employ the simple series expression for first higher order modal field for graded index fiber. The evaluation of the concerned parameters based on our formalism requires very little computations. Here, we show that our estimations match excellently well with the exact results in case of step and parabolic index fibers. Further, splice being highly tolerant for longitudinal separation, our analysis is judiciously restricted to the case of transverse and angular mismatches only. The analysis should find application in dual mode graded index fiber in all optical technology. 相似文献
68.
Dibakar Sahoo Prosenjit Bhattacharya Hirak Kumar Patra Paulami Mandal Sankar Chakravorti 《Journal of nanoparticle research》2011,13(12):6755-6760
Change of α-helical structure of heme protein (Hb) to a β-sheet and random coil conformation because of the interaction of
glycine capped gold nanoparticles (20–60 nm) as observed from attenuation total reflectance, absorption, Fourier transform
infra red, and Circular Dichroism spectroscopy has been reported in this article. Upon interaction, protein takes a cylindrical
shape of length 12 μm and diameter 0.35 μm as revealed from scanning electron microscopy and transmission electron microscopy.
The Selected-Area Electron beam Diffraction pattern shows change of crystalline structure in GNP to amorphous nature with
the interaction of Hb. 相似文献
69.
N. Rajeswari Yogamalar A. Chandra Bose 《Applied Physics A: Materials Science & Processing》2011,103(1):33-42
Nanopowders of pure and lithium-doped semiconducting ZnO (Zn1−x
Li
x
O, where x= 0, 0.01, 0.03, 0.06, 0.09 and 0.15 in atomic percent (at.%)) are prepared by PEG-assisted low-temperature hydrothermal method.
The average crystallite size is calculated using Debye–Scherrer formula and corrected for strain-induced broadening by Williamson–Hall
(W–H) plot. The peak shift in XRD and the lattice constant of ZnO as a function of unit cell composition are predicted by
Vegard’s law. The evolution of ZnO nanostructures from rod-shaped to particle nature is observed from TEM images and the influence
of dopant on the morphology is investigated. The optical absorption measurement marks an indication that the incorporation
of lithium ion into the lattice of ZnO widens the optical band gap energy from ∼2.60 to ∼3.20 eV. The near band edge (NBE)
emission peak centered at ∼3.10 eV is considered to be the dominant emission peak in the PL spectra. Blue emission peak is
not observed in doped ZnO, thus promoting defect-free nanoparticles. The Burstein–Moss shift serves as a qualitative tool
to analyze the widening of the optical band gap and to study the shape of the NBE luminescence in doped ZnO nanopowders. FT-IR
spectra are used to identify the strong metal–oxide (Zn–O) interaction. 相似文献
70.
Structural and optical properties of RF magnetron sputtered aluminum nitride films without external substrate heating 总被引:1,自引:0,他引:1
Atul Vir Singh Sudhir ChandraA.K. Srivastava B.R. ChakrobortyG. Sehgal M.K. DalaiG. Bose 《Applied Surface Science》2011,257(22):9568-9573
We report structural and optical properties of aluminum nitride (AlN) thin films prepared by RF magnetron sputtering. A ceramic AlN target was used to sputter deposit AlN films without external substrate heating in Ar-N2 (1:1) ambient. The X-ray diffraction and high resolution transmission electron microscopy results revealed that the films were preferentially oriented along c-axis. Cross-sectional imaging revealed columnar growth perpendicular to the substrate. The secondary ion mass spectroscopy analysis confirmed that aluminum and nitrogen distribution was uniform within the thickness of the film. The optical band gap of 5.3 eV was evaluated by UV-vis spectroscopy. Photo-luminescence broad band was observed in the range of 420-600 nm with two maxima, centered at 433 nm and 466 nm wavelengths related to the energy states originated during the film growth. A structural property correlation has been carried out to explore the possible application of such important well oriented nano-structured two-dimensional semiconducting objects. 相似文献