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11.
Ruthenium(III) has been precipitated gravimetrically in the pH range 7.0-8.5 with morpholine-4-carbodithioate and determined by weighing as a black complex (C5H6ONS2)3 Ru after drying at l00–110°C. The interference of the various metal ions has been avoided by using an ammonical mixture of EDTA and tartrate (1:1 molar ratio). The complex is thermally stable up to l60°C.  相似文献   
12.
Magnetic iron oxide nanoparticles are inherently biocompatible and are amenable to post synthesis surface modification, making them excellent candidates for many important applications. If the above can be achieved in a single-step i.e., in situ synthesis and functionalization, the results are expected to be more dramatic for sensitive detection of biomolecules. For any application, it is necessary to confer a high level of binding specificity through surface chemistry, which can be introduced by using biological moieties that possess lock-and-key interactions, like those observed in antibody-antigen and enzyme-substrate recognition. In this paper, we have synthesized water based ferrofluids with serum albumin, the major protein component of blood. A series of other ferrofluids using different biocompatible polymers have also been studied with respect to their size determined by transmission electron microscopy, magnetic behavior with the aid of vibrating sample magnetometry and binding capability to bovine serum albumin by quenching of its native fluorescence. From our results, it can be inferred that binding has taken place between magnetic particles and biomolecules, the binding constants of which indirectly reveal the efficiency of the interaction.  相似文献   
13.
CF3H as a proton donor was paired with a variety of anions, and its properties were assessed by MP2/aug‐cc‐pVDZ calculations. The binding energy of monoanions halide, NO3?, formate, acetate, HSO4?, and H2PO4? lie in the 12–17 kcal mol?1 range, although F? is more strongly bound, by 26 kcal mol?1. Dianions SO42? and HPO42? are bound by 27 kcal mol?1, and trianion PO43? by 45 kcal mol?1. When two O atoms are available on the anion, the CH???O? H‐bond (HB) is usually bifurcated, although asymmetrically. The CH bond is elongated and its stretching frequency redshifted in these ionic HBs, but the shift is reduced in the bifurcated structures. Slightly more than half of the binding energy is attributed to Coulombic attraction, with smaller contributions from induction and dispersion. The amount of charge transfer from the anions to the σ*(CH) orbital correlates with many of the other indicators of bond strength, such as binding energy, CH bond stretch, CH redshift, downfield NMR spectroscopic chemical shift of the bridging proton, and density at bond critical points.  相似文献   
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15.
Dibasic tridentate Schiff bases obtained by the condensation of O -aminobenzoic acid with salicyldehyde and its 5-chloro and 5-bromo derivatives were synthesised and used to pracipitate Zr(IV), Th(IV) and UO2(VI) metals as complexes. The 1:1 (metal-ligand) stoichiometry of these complexes is shown by elemental analysis, gravimetric estimations and conductometric titrations while the structures of the complexes are proved by i.r. spectra and thermogravimetric analysis. The magnetic susceptibility measurements by Gouy method show, these complexes to be monormeic and diamagnetic. The molar conductance values in nitrobenzene indicate the nonelectrolytic behaviour of the complexes. The results show that the complexes of the type Zr(OH)2L.H2O, Th(OH)2L.H2O and UO2L.H2O are formed having solvent molecule in co-ordination with metal ion.  相似文献   
16.
We examine the effect of viscous forces on the displacement of one fluid by a second, immiscible fluid along parallel layers of contrasting porosity, absolute permeability and relative permeability. Flow is characterized using five dimensionless numbers and the dimensionless storage efficiency, so results are directly applicable, regardless of scale, to geologic carbon storage. The storage efficiency is numerically equivalent to the recovery efficiency, applicable to hydrocarbon production. We quantify the shock-front velocities at the leading edge of the displacing phase using asymptotic flow solutions obtained in the limits of no crossflow and equilibrium crossflow. The shock-front velocities can be used to identify a fast layer and a slow layer, although in some cases the shock-front velocities are identical even though the layers have contrasting properties. Three crossflow regimes are identified and defined with respect to the fast and slow shock-front mobility ratios, using both theoretical predictions and confirmation from numerical flow simulations. Previous studies have identified only two crossflow regimes. Contrasts in porosity and relative permeability exert a significant influence on contrasts in the shock-front velocities and on storage efficiency, in addition to previously examined contrasts in absolute permeability. Previous studies concluded that the maximum storage efficiency is obtained for unit permeability ratio; this is true only if there are no contrasts in porosity and relative permeability. The impact of crossflow on storage efficiency depends on the mobility ratio evaluated across the fast shock-front and on the time at which the efficiency is measured.  相似文献   
17.
Matching product architecture with supply chain design   总被引:1,自引:0,他引:1  
Product architecture is typically established in the early stages of the product development (PD) cycle. Depending on the type of architecture selected, product design, manufacturing processes, and ultimately supply chain configuration are all significantly affected. Therefore, it is important to integrate product architecture decisions with manufacturing and supply chain decisions during the early stage of the product development. In this paper, we present a multi-objective optimization framework for matching product architecture strategy to supply chain design. In contrast to the existing operations management literature, we incorporate the compatibility between the supply chain partners into our model to ensure the long term viability of the supply chain. Since much of the supplier related information may be very subjective in nature during the early stages of PD, we use fuzzy logic to compute the compatibility index of a supplier. The optimization model is formulated as a weighted goal programming (GP) model with two objectives: minimization of total supply chain costs, and maximization of total supply chain compatibility index. The GP model is solved by using genetic algorithm. We present case examples for two different products to demonstrate the model’s efficacy, and present several managerial implications that evolved from this study.  相似文献   
18.
Complexes of Cu(II), Ni(II) and Co(II) with the Schiff bases derived from o-aminobenzoic acid with salicylaldehyde and its 5-chloro and 5-bromo derivatives have been prepared. The 1:1 (metal-ligand) stoichiometry of these complexes is shown by elemental analysis, gravimetric estimations and conductometric titrations while the structures of the complexes are proved by i.r. spectra and thermogravimetric analysis. The magnetic susceptibility and electronic spectra of Cu(II) complexes indicate the nonplanar binuclear structures while that of Ni(II) and Co(II) show their paramagnetic octahedral geometry. The molar conductance values in nitrobenzene indicate the nonelectrolytic behaviour of the complexes. The results show that the complexes of the type (Cu·L)2, Ni·L·3H2O and Co·L·3H2O are formed having solvent molecule in coordination with the metal ion. The monopyridine and monoammonia adducts of Cu(II) complexes were found to be monomeric.  相似文献   
19.
ABSTRACT

High pressure processing (HPP) and sous vide may increase the shelf-life of high value seafood products without the use of additives. This study investigated the effects of 150MPa or 350MPa for 10min on microbial, sensory, and physicochemical qualities of raw and subsequently sous vide cooked (65°C) lobster tails during 28 days of refrigerated storage. Raw lobster pressurized at 350MPa or sous vide cooked maintained significantly lower microbial counts, total volatile base nitrogen, and biogenic amine levels. Due to off-odors, 90% and 60% of sensory respondents rejected the control and 150MPa raw samples, respectively, by day 7, while 70% rated the 350MPa samples as still acceptable on day 28. For cooked lobster, only 20% of the respondents rejected any samples by day 28. Moderate HPP conditions were effective in extending refrigerated shelf-life of vacuum-packaged raw lobster tails. However, HPP pretreatment did not contribute to additional shelf-life extension for sous vide cooked products.  相似文献   
20.
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