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61.
62.
We consider the open shop scheduling problem with two machines. Each job consists of two operations, and it is prescribed that the first (second) operation has to be executed by the first (second) machine. The order in which the two operations are scheduled is not fixed, but their execution intervals cannot overlap. We are interested in the question whether, for two given values D1 and D2, there exists a feasible schedule such that the first and second machine process all jobs during the intervals [0,D1] and [0,D2], respectively.We formulate four simple conditions on D1 and D2, which can be verified in linear time. These conditions are necessary and sufficient for the existence of a feasible schedule. The proof of sufficiency is algorithmical, and yields a feasible schedule in linear time. Furthermore, we show that there are at most two non-dominated points (D1,D2) for which there exists a feasible schedule. 相似文献
63.
Marjan Borazjani Ali Mehdinia Ali Jabbari 《Journal of Solid State Electrochemistry》2018,22(2):355-363
An electrochemical chiral sensor was designed based on graphene (GR) as a catalyst for signal enhancement. Hydrocortisone has been immobilized as a chiral selector on GR to discriminate electrochemical signals of mandelic acid (MA) enantiomers. A two-step electrodeposition strategy was used to fabricate hydrocortisone-loaded overoxidized polypyrrole film (HC-OPPy) on graphene-modified glassy carbon electrode, which was successfully utilized as a working electrode for direct monitoring of MA enantiomers based on an inhibitory sensing mechanism. The stepwise modification of the surface was confirmed by cyclic voltammetry, impedance spectroscopy, and scanning electron microscopy. Because of the different interactions of enantiomers with the chiral electroactive platform, voltammetric signals with different intensities were observed for S-MA and R-MA at 1.36 and 1.40 V (vs. Ag/AgCl), respectively. The introduced design for the chiral sensor, with exploiting the chemometrics tools such as partial least squares, principle component regression, and genetic algorithm, was able to discriminate highly overlapping signals of MA enantiomers in their mixtures. The hydrocortisone-based sensor showed a linear response towards MA enantiomers within a concentration range of 1.0–25 mM with a detection limit of 0.25 mM (S/N = 3). The sensor not only extends the enantioselective sensing of MA enantiomers but also stimulates new opportunities for investigating stereo-selective behavior of hydrocortisone. The recognition mechanism was also investigated using docking analysis and DFT calculations. 相似文献
64.
The velocity dependence of collision broadening cross sections for both self-broadening and Xe broadening of an infrared transition in NH3 has been studied by measuring laser saturation resonance linewidths for molecules with specified velocities along the laser propagation direction. For self-broadening, the velocity dependence is in accord with inelastic collisions due to a predominantly dipole-dipole interaction potential, with smaller contributions due to shorter range forces, whereas for Xe broadening, the magnitude and velocity dependence of the collision broadening cross section is in better agreement with velocity changing collisions in the pressure range studied. 相似文献
65.
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67.
Marjan Matvejchuk 《International Journal of Theoretical Physics》2011,50(12):3852-3856
Let B(H)
Id
be the set of all bounded idempotents on a Hilbert space H. Fix p∈B(H)
Id
. The aim of the paper is to show a set of symmetries J on H for which p is a J-projection. 相似文献
68.
Effect of Partially Hydrolyzed Kappa-Casein on Physicochemical and Sensory Properties of Heated Milk
Marjan Nouri Soleiman Abbasi Mehdi Aminafshar Homa Behmadi 《Journal of Dispersion Science and Technology》2013,34(8):1204-1209
The chemical, physical, and sensory characteristics of renneted skim milk (RSM) containing partially hydrolyzed κ-casein were assessed and compared with skim milk (control). Rennet was added to heated milk (60°C for 15 minutes) at seven concentrations from 0.1 to 0.7 mL rennet/100 mL milk followed by heating to 63°C for 30 minutes in order to inactivate the rennet. The RSM samples had higher viscosity as well as whiter, yellower, and greener color in comparison with control sample. The range of size distribution of casein aggregates was larger than that of skim milk, while being within the range of fat mimetics. 相似文献
69.
Susanne Vo? Vadim Nigmatoulline Marjan Bele Stane Pejovnik Jürgen O. Besenhard 《Monatshefte für Chemie / Chemical Monthly》2001,35(2):487-497
A widely applicable aqueous dip-coating process termed substrate induced coagulation (SIC) suitable for coating various types of substrates (e.g. polar and unpolar polymers, inorganic glasses, metals) with fine particulate materials (e.g. carbon blacks, small particle size SiO2 or TiO2) has been developed. This process is based on the interaction of a conditioner (water soluble polymers or polyelectrolytes, e.g. proteins, polyvinylalcohols, polyacrylates with low charge density) which is adsorbed on the substrate with a surfactant-stabilized dispersion containing some additional electrolyte. Employing dispersions of conductive particles, the resulting coatings can be used as a conductive starting layer for electroplating. Such layers are fairly rinse-proof and may be applied in the metallization process of through holes in printed wiring boards or for the production of highly conductive composite materials from coated particles. SIC has also been used to improve the distribution of carbon in composite battery electrodes such as MnO2/C. 相似文献
70.
Marjan Gòrski F. Emich A. Rosenheim und R. Cohn 《Fresenius' Journal of Analytical Chemistry》1916,55(4):191-195
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