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61.
62.
Cross docking terminals allow companies to reduce storage and transportation costs in a supply chain. At these terminals, products of different types from incoming trucks are unloaded, sorted, and loaded to outgoing trucks for delivery. If the designated outgoing truck is not immediately available for some products, they are temporarily stocked in a small storage area available at the terminal. This paper focuses on the operational activities at a cross docking terminal with two doors: one for incoming trucks and another one for outgoing trucks. We consider the truck scheduling problem with the objective to minimize the storage usage during the product transfer inside the terminal. Our interest in this problem is mainly theoretical. We show that it is NP-hard in the strong sense even if there are only two product types. For a special case with fixed subsequences of incoming and outgoing trucks, we propose a dynamic programming algorithm, which is the first polynomial algorithm for this case. The results of numerical tests of the algorithm on randomly generated instances are also presented.  相似文献   
63.
β-glucans are known as biological response modifiers. However, different sources can result in structural differences and as a result differences in their biological activity. The hot water extraction method allows to obtain, high molecular weight β-glucans without altering their structure by using strong chemicals, such as alkalis or acids. Analysis of β-glucans by FT-IR and NMR spectroscopy in solid state is superior to analysis in solution as it allows researchers to study the preserved structure of the extracted polysaccharides. FT-IR spectroscopy was used in this study to make side-by-side comparison analysis of hot water extracted β-glucans from different yeast sources. NMR spectroscopy was used to confirm findings made by FT-IR spectroscopy. Extracted β-glucans exhibit characteristic structure of β-1,3/1,6-linked glucans with noticeable levels of proteins, possibly in a form of oligopeptides, chitin and other impurities. β-glucans obtained from C. guilliermondii, P. pastoris and S. pastorianus exhibited higher protein content. Differences in mannan, chitin and α-glucan content were also observed; however, the species-specific structure of obtained β-glucans could not be confirmed without additional studies. Structural analysis of high molecular weight β-glucans in solid state by FT-IR spectroscopy is difficult or limited due to band intensity changes and overlapping originating from different molecules.  相似文献   
64.
Russian Journal of Coordination Chemistry - Complexes [Zn(L)Cl2] (I), Cu(L)Cl2 ? H2O (II), Zn(L1)Cl2 ? 0.5H2O (III), and Cu(L1)Cl2 ? 0.5H2O (IV) (where L and L1 are the...  相似文献   
65.
In this paper we obtain, for the first time in the literature a new numerical pair. The properties of the new pair are:
  1. 1.
    symmetric two-step algorithm,
     
  2. 2.
    four-stages scheme,
     
  3. 3.
    scheme of tenth-algebraic order,
     
  4. 4.
    the approximations of the layers are taken place as follows: first and second layer on the point \(x_{n-1}\), third layer on the point \(x_{n}\), fourth layer on the point \(x_{n+1}\),
     
  5. 5.
    the method has eliminated the phase-lag and its first derivative,
     
  6. 6.
    excellent stability and interval of periodicity properties (i.e. interval of periodicity equal to \(\left( 0, \infty \right) \).
     
For this new numerical pair we present a detailed theoretical analysis. Finally, we prove the efficiency of the new scheme by applying it to the solution of systems of coupled Schrödinger equations.
  相似文献   
66.
We prove the algebraicity of smooth -mappings between algebraic Cauchy-Riemann manifolds. A generalization of separate algebraicity principle is established.

  相似文献   

67.
As part of our general QSPR treatment of solubility (started in the preceding paper), we now present quantitative relationships between solvent structures and the solvation free energies of individual solutes. Solvation free energies of 80 diverse organic solutes are each modeled in a range from 15 to 82 solvents using our CODESSA PRO software. Significant correlations (in terms of squared correlation coefficient) are found for all the 80 solutes: the best fit is obtained for n-propylamine (R(2) = 0.996); the lowest R(2) corresponds to toluene (0.604).  相似文献   
68.
Russian Chemical Bulletin - N-Heterocycle-containing (1S)-(+)-camphor-10-sulfonamide derivatives were synthesized. Their antiviral activity against the Ebola and Marburg viruses was estimated using...  相似文献   
69.
Reactions of a chalcone derivative (synthesized earlier from usnic acid) with various oxidants (hydrogen peroxide, tert-butyl hydroperoxide, and dichlorodicyanobenzoquinone) gave new flavonols, dihydroflavonols, and flavones. Treatment of the starting chalcone with a nucleophilic reagent (NH2NH2·H2O) afforded a dihydropyrazole-containing derivative.  相似文献   
70.
The synthesis of multisubstituted 4-nitrobuta-1,3-dien-1-amines (nitrodienamines) from 3-aminocrotonates and nitroacetaldehyde potassium salt, has been performed in 45–89% yields. This one-step protocol works efficiently with a broad range of N-H and N-substituted 3-aminocrotonates and delivers both primary and secondary nitrodienamines. In addition, the possible variations of the substituents at the positions 2 and 3 of 4-nitrobuta-1,3-dien-1-amine have been shown. Generally, the yields of secondary 4-nitrobuta-1,3-dien-1-amines were lower than those of primary ones. The synthetic usefulness of obtained 4-nitrobuta-1,3-dien-1-amines has also been demonstrated by achieving the synthesis of multisubstituted 5-nitro-1,6-dihydropyridines in two-component cyclocondensation reactions of 4-nitrobuta-1,3-dien-1-amines with aromatic or aliphatic aldehydes. Lastly, diverse N-H and N-substituted 5-nitro-1,6-dihydropyridines have been obtained in 35–87% yields.  相似文献   
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