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131.
Kunpeng Li Appa Iyer Sivakumar Viswanath Kumar Ganesan 《European Journal of Operational Research》2008
In this paper, we study the problem of synchronized scheduling of assembly and air transportation to achieve accurate delivery with minimized cost in consumer electronics supply chain. This problem was motivated by a major PC manufacturer in consumer electronics industry. The overall problem is decomposed into two sub-problems, which consist of an air transportation allocation problem and an assembly scheduling problem. The air transportation allocation problem is formulated as an integer linear programming problem with the objective of minimizing transportation cost and delivery earliness tardiness penalties. The assembly scheduling problem seeks to determine a schedule ensuring that the orders are completed on time and catch the flights such that the waiting penalties between assembly and transportation is minimized. The problem is formulated as a parallel machine scheduling problem with earliness penalties. The computational complexities of the two sub-problems are investigated. The air transportation allocation problem with split delivery is shown to be solvable. The parallel machine assembly scheduling problem is shown to be NP-complete. Simulated annealing based heuristic algorithms are presented to solve the parallel machine problem. 相似文献
132.
Crystallography Reports - In title compound bis(2,5-dichloroanilinium) sulfate, the equally disordered sulfate anion occupies 2-fold rotation axis with equivalent component generated through the... 相似文献
133.
Benzopyran fused tetra and pentacyclic frameworks have been synthesized by the domino Knoevenagel hetero Diels–Alder (DKHDA) reaction using various 1,3-diones with O-allylated salicylaldehydes and O-propargylated salicylaldehydes in a solvent and catalyst free condition via Solid-State Melt Reaction (SSMR). The reaction requires only a single step operation thus providing potentially bioactive polycyclic heterocycles in high yields. 相似文献
134.
Sk.Khadeer Pasha V.S.V.Satyanarayana A.Sivakumar K.Chidambaram L.John Kennedy 《中国化学快报》2011,22(8):891-894
Several 2,5-dimethyl-N-substituted pyrroles were prepared by the condensation of different substituted anilines with 2,5- hexanedione using nano lead oxide as an efficient and recyclable catalyst.All the synthesized compounds are confirmed through IR, 1H NMR,13C NMR and mass spectral data.Nano lead oxide β-PbO(P85) was prepared by dissolving lead acetate dihydrate in 1- propanol at a pH 9.0 under stirring at 85℃.The structural study and surface morphology of the lead oxide(PbO) were characterized using X-ray diffraction(XRD),Scanning electron microscopy(SEM) and the functional groups of the PbO sample were investigated using infrared spectrophotometer. 相似文献
135.
Monica S. Esther Santhoshi Dhas C. Ravi Venkatesh R. Sivakumar R. Vignesh R. Ferby V. Anslin 《Journal of Solid State Electrochemistry》2022,26(5):1271-1290
Journal of Solid State Electrochemistry - Herein, we have analyzed for the first time on the synergetic effect of NiO and MnOx towards electrochromic behaviour in comparison with pristine NiO films... 相似文献
136.
R. Jagan D. Sathya K. Sivakumar 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(5):374-380
In the salt 1‐methylpiperazine‐1,4‐diium bis(dihydrogen phosphate), C5H13N22+·2H2PO4−, (I), and the solvated salt 2‐(pyridin‐2‐yl)pyridinium dihydrogen phosphate–orthophosphoric acid (1/1), C10H9N2+·H2PO4−·H3PO4, (II), the formation of O—H...O and N—H...O hydrogen bonds between the dihydrogen phosphate (H2PO4−) anions and the cations constructs a three‐ and two‐dimensional anionic–cationic network, respectively. In (I), the self‐assembly of H2PO4− anions forms a two‐dimensional pseudo‐honeycomb‐like supramolecular architecture along the (010) plane. 1‐Methylpiperazine‐1,4‐diium cations are trapped between the (010) anionic layers through three N—H...O hydrogen bonds. In solvated salt (II), the self‐assembly of H2PO4− anions forms a two‐dimensional supramolecular architecture with open channels projecting along the [001] direction. The 2‐(pyridin‐2‐yl)pyridinium cations are trapped between the open channels by N—H...O and C—H...O hydrogen bonds. From a study of previously reported structures, dihydrogen phosphate anions show a supramolecular flexibility depending on the nature of the cations. The dihydrogen phosphate anion may be suitable for the design of the host lattice for host–guest supramolecular systems. 相似文献
137.
Nickel-Impregnated Silica Nanoparticle Synthesis and Their Evaluation for Biocatalyst Immobilization
Reddy Shetty Prakasham G. Sarala Devi Chaganti Subba Rao V. S. S. Sivakumar T. Sathish P. N. Sarma 《Applied biochemistry and biotechnology》2010,160(7):1888-1895
In the present investigation, impact of nickel-impregnated silica paramagnetic particles (NSP) as biocatalyst immobilization
matrices was investigated. These nanoparticles were synthesized by sol–gel route using a nonionic surfactant block co polymer
[poly (ethylene glycol)-block-poly-(propylene glycol)-block-poly (ethylene glycol)]. Diastase enzyme was immobilized on these particles (enzyme-impregnated NSP) as model enzyme and
characterized using Fourier-transform infrared spectroscopy and X-ray crystallography. Analysis of enzyme-binding nature with
these nanoparticles at different physiological conditions revealed that binding pattern and activity profile varied with the
pH of the reaction mixture. The immobilized enzyme was further characterized for its biocatalytic activity with respect to
kinetic properties such as Km and Vmax and compared with free enzyme. Paramagnetic nanoparticle-immobilized enzyme showed
more affinity for substrate compared to free one. The nature of silica and nickel varied from amorphous to crystalline nature
and vice versa upon immobilization of enzyme. To the best of our knowledge, this is the first report of its kind for change
of nature from one form to other under normal temperatures upon diastase interaction with NSP. 相似文献
138.
Hou G Paramasivam S Byeon IJ Gronenborn AM Polenova T 《Physical chemistry chemical physics : PCCP》2010,12(45):14873-14883
In this paper, we present 3D chemical shift anisotropy (CSA)/dipolar coupling correlation experiments, based on γ-encoded R-type symmetry sequences. The γ-encoded correlation spectra are exquisitely sensitive to the relative orientation of the CSA and dipolar tensors and can provide important structural and dynamic information in peptides and proteins. We show that the first-order (m = ±1) and second-order (m = ±2) Hamiltonians in the R-symmetry recoupling sequences give rise to different correlation patterns due to their different dependencies on the crystallite orientation. The relative orientation between CSA and dipolar tensors can be determined by fitting the corresponding correlation patterns. The orientation of (15)N CSA tensor in the quasi-molecular frame is determined by the relative Euler angles, α(NH) and β(NH), when the combined symmetry schemes are applied for orientational studies of (1)H-(15)N dipolar and (15)N CSA tensors. The correlation experiments introduced here work at moderate magic angle spinning frequencies (10-20 kHz) and allow for simultaneous measurement of multiple sites of interest. We studied the orientational sensitivity of γ-encoded symmetry-based recoupling techniques numerically and experimentally. The results are demonstrated on [(15)N]-N-acetyl-valine (NAV) and N-formyl-Met-Leu-Phe (MLF) tripeptide. 相似文献
139.
The title salts, 4‐chloroanilinium hydrogen phthalate (PCAHP), C6H7ClN+·C8H5O4−, 2‐hydroxyanilinium hydrogen phthalate (2HAHP), C6H8NO+·C8H5O4−, and 3‐hydroxyanilinium hydrogen phthalate (3HAHP), C6H8NO+·C8H5O4−, all crystallize in the space group P21/c. The asymmetric unit of 2HAHP contains two independent ion pairs. The hydrogen phthalate ions of 2HAHP and 3HAHP show a short intramolecular O—H...O hydrogen bond, with O...O distances ranging from 2.3832 (15) to 2.3860 (14) Å. N—H...O and O—H...O hydrogen bonds, together with short C—H...O contacts in PCAHP and 3HAHP, generate extended hydrogen‐bond networks. PCAHP forms a two‐dimensional supramolecular sheet extending in the (100) plane, whereas 2HAHP has a supramolecular chain running parallel to the [100] direction and 3HAHP has a two‐dimensional network extending parallel to the (001) plane. 相似文献
140.
Let X be a partially ordered real Banach space, let a,b∈X with a≤b. Let φ be a bounded linear functional on X. We say that X satisfies the box-optimization property (or X is a BOP space) if the box-constrained linear program: max 〈φ,x〉, s.t. a≤x≤b, has an optimal solution for any φ,a and b. Such problems arise naturally in solving a class of problems known as interval linear programs. BOP spaces were introduced (in a different language) and systematically studied in the first author’s doctoral thesis. In this paper, we identify new classes of Banach spaces that are BOP spaces. We present also sufficient conditions under which answers are in the affirmative for the following questions:
相似文献
- (i)When is a closed subspace of a BOP space a BOP space?
- (ii)When is the range of a bounded linear map a BOP space?
- (iii)Is the quotient space of a BOP space a BOP space?