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排序方式: 共有387条查询结果,搜索用时 187 毫秒
1.
This paper considers the job (lot) scheduling problem for two-stage flow shops in which the movement of transfer batches (sublots) from the first stage to the next are allowed. Set-up, processing and removal times are considered as separable and independent of the order in which jobs are processed at any of two stages. An optimal transfer batch sizing and scheduling algorithm which has an objective of minimizing the maximum flow time (makespan) is developed and demonstrated by a numerical example.  相似文献   
2.
This study aims to clarify the effects of carbon activation type and physical form on the extent of adsorption capacity and desorption capacity of a bi-solute mixture of phenol and 2-chlorophenol (2-CP). For this purpose, two different PACs; thermally activated Norit SA4 and chemically activated Norit CA1, and their granular countertypes with similar physical characteristics, thermally activated Norit PKDA and chemically activated Norit CAgran, were used. The thermally activated carbons were better adsorbers for phenol and 2-CP compared with chemically activated carbons, but adsorption was more reversible in the latter case. 2-CP was adsorbed preferentially by each type of activated carbon, but adsorption of phenol was strongly suppressed in the presence of 2-CP. The simplified ideal adsorbed solution (SIAS) model underestimated the 2-CP loadings and overestimated the phenol loadings. However, the improved and modified forms of the SIAS model could better predict the competitive adsorption. The type of carbon activation was decisive in the application of these models. For each activated carbon type, phenol was desorbed more readily in the bi-solute case, but desorption of 2-CP was less compared with single-solute. This was attributed to higher energies of 2-CP adsorption.  相似文献   
3.
Coskun A  Deniz E  Akkaya EU 《Organic letters》2005,7(23):5187-5189
[reaction, structure: see text] We report a unimolecular system functioning as a combinatorial logic circuit for half-subtractor. The emission characteristics can be modulated by chemical inputs, and when followed at two different wavelengths, two functionally integrated logic gates XOR and INHIBIT are obtained. Both logic gates function in the emission mode, and with very large differences in the signal intensity allowing unequivocal assignment of logic-0 and logic-1.  相似文献   
4.
We report a novel dimeric boradiazaindacene dye which can be converted in one step to an efficient resonance energy transfer (RET) dyad. In addition, if this modification is done with appropriate ligands, RET can be coupled to ion sensing. The utility of this approach is demonstrated in a highly selective, emission ratiometric chemosensor for Ag(I).  相似文献   
5.
Infrared bands mainly associated with v(M—X2) stretching modes (M = Pd or Pt, and X = Cl, Br, or P) have been identified in the spectra of 35 carbene complexes. Based on these results and on |1J| (31 P—195 Pt) the trans-influence of the carbene ligands is assessed.  相似文献   
6.
The title complex, [PdCl2(C21H26N2)(C18H15P)], shows slightly distorted square‐planar coordination around the PdII metal centre. The Pd—C bond distance between the N‐heterocyclic ligand and the metal atom is 2.028 (5) Å. The dihedral angle between the two trimethylphenyl ring planes is 36.9 (2)°.  相似文献   
7.
The 2- or 2,6-position(s) of aromatic aldehydes were directly and selectively arylated with aryl chlorides or bromides in the presence of a catalytic system prepared in situ from Pd(OAc)2, imidazolinium chlorides (1-5) and Cs2CO3.  相似文献   
8.
The title complex, di‐μ‐chloro‐bis­[chloro­(η6p‐cymene)ruthenium(II)]–9H‐carbazole (1/2), [Ru2Cl4(C10H14)2]·2C12H9N, is composed of one [RuCl26p‐cymene)]2 and two 9H‐carbazole mol­ecules. There are one‐half of a dinuclear complex and one 9H‐carbazole mol­ecule per asymmetric unit. In the dinuclear complex, each of the two crystallographically equivalent Ru atoms is in a pseudo‐tetra­hedral environment, coordinated by a terminal Cl atom, two bridging Cl atoms and the aromatic hydro­carbon, which is linked in a η6 manner; the Ru⋯Ru separation is 3.688 (3) Å. The title complex has a crystallographic centre of symmetry located at the mid‐point of the Ru⋯Ru line. Inter­molecular N—H⋯Cl and π–π stacking inter­actions are observed. These inter­actions form a four‐pointed star‐shaped ring and one‐dimensional linear chains of edge‐fused rings running parallel to the [100] direction, which stabilize the crystal packing.  相似文献   
9.
Piano‐stool ([(p‐cymene)Ru(thz)Cl], 2 ) and six‐coordinated ([Ru(thz)2(PPh3)2], 3 ) ruthenium complexes derived from 2‐phenylthiazoline‐4‐carboxylic acid (Hthz, 1 ) were synthesized for the first time, and fully characterized using conventional methods. Also, the molecular structure of complex 3 was determined using X‐ray analysis. These complexes were evaluated as catalysts for transfer hydrogenation of carbonyl compounds in the presence of isopropyl alcohol and KOtBu. Complex 2 was found to be more active than 3 in transfer hydrogenation. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
10.
It has been demonstrated that type-2 fuzzy logic systems are much more powerful tools than ordinary (type-1) fuzzy logic systems to represent highly nonlinear and/or uncertain systems. As a consequence, type-2 fuzzy logic systems have been applied in various areas especially in control system design and modelling. In this study, an exact inversion methodology is developed for decomposable interval type-2 fuzzy logic system. In this context, the decomposition property is extended and generalized to interval type-2 fuzzy logic sets. Based on this property, the interval type-2 fuzzy logic system is decomposed into several interval type-2 fuzzy logic subsystems under a certain condition on the input space of the fuzzy logic system. Then, the analytical formulation of the inverse interval type-2 fuzzy logic subsystem output is explicitly driven for certain switching points of the Karnik–Mendel type reduction method. The proposed exact inversion methodology driven for the interval type-2 fuzzy logic subsystem is generalized to the overall interval type-2 fuzzy logic system via the decomposition property. In order to demonstrate the feasibility of the proposed methodology, a simulation study is given where the beneficial sides of the proposed exact inversion methodology are shown clearly.  相似文献   
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