A fast hybrid tabu search algorithm for the no-wait job shop problem

This paper describes a hybrid tabu search algorithm dedicated to a job shop problem with a no-wait constraint with a makespan criterion. The proposed here algorithm complexity is that the superior algorithm based on the tabu search technique selects parameters controlling the work of a certain constructional algorithm. This approach limits the checked solutions only to a group of solutions being able to be generated by the structural algorithm in question. It bears serious consequences both positive, for example it limits the research scope for a small fraction of relatively extremely well quality of acceptable solutions, and negative that is the lack of possibility of finding the optimal solution. In this paper numerical researches of the proposed algorithm are conducted as well as a comparative analysis with reference to the literature algorithms of the algorithm in question is made.     

Effects of killing conditions of vanilla (Vanilla planifolia,Andrews) pods during the curing process on aroma composition of pod ethanol extract

The effects on the aroma compositions of ethanol extracts obtained by traditional and enzyme‐assisted methods from seven killing conditions used in vanilla pod curing were studied. Two procedures of vanilla pod killing consisted of either freezing pods at ?10 °C for 24 h or immersing pods in 80 °C water for 10 s each of three times with 30 s intervals resulted in the highest vanillin values in terms percentage of dry weight of the bean (2.84 and 2.96), 4‐hydroxybenzaldehyde (0.18 and 0.20), vanillyl alcohol (0.56 and 0.57) and vanillic acid (0.18 and 0.19 respectively) when traditional vanilla ethanol extraction was used. When this extract was aged for 3 months it showed improvement in flavour compounds. Enzyme‐assisted vanilla ethanol extraction showed a higher content of flavour compounds than traditional extract, for example vanillin 4.38% and 2.96% respectively. Only vanillic acid levels were improved after ageing of the enzyme‐assisted extracts.     

Potential of Bacterial Cellulose Chemisorbed with Anti-Metabolites, 3-Bromopyruvate or Sertraline,to Fight against Helicobacter pylori Lawn Biofilm

Helicobacter pylori is a bacterium known mainly of its ability to cause persistent inflammations of the human stomach, resulting in peptic ulcer diseases and gastric cancers. Continuous exposure of this bacterium to antibiotics has resulted in high detection of multidrug-resistant strains and difficulties in obtaining a therapeutic effect. The purpose of the present study was to determine the usability of bacterial cellulose (BC) chemisorbed with 3-bromopyruvate (3-BP) or sertraline (SER) to act against lawn H. pylori biofilms. The characterization of BC carriers was made using a N2 adsorption/desorption analysis, tensile strength test, and scanning electron microscopy (SEM) observations. Determination of an antimicrobial activity was performed using a modified disk-diffusion method and a self-designed method of testing antibacterial activity against biofilm microbial forms. In addition, bacterial morphology was checked by SEM. It was found that BC disks were characterized by a high cross-linking and shear/stretch resistance. Growth inhibition zones for BC disks chemisorbed with 2 mg of SER or 3-BP were equal to 26.5–27.5 mm and 27–30 mm, respectively. The viability of lawn biofilm H. pylori cells after a 4-h incubation with 2 mg SER or 3-BP chemisorbed on BC disks was ≥4 log lower, suggesting their antibacterial effect. SEM observations showed a number of morphostructural changes in H. pylori cells exposed to these substances. Concluding, SER and 3-BP chemisorbed on BC carriers presented a promising antibacterial activity against biofilm H. pylori cells in in vitro conditions.     

The reuse of brine to enhance the ripening of marine and freshwater fish resistant to marinating

Cold marinades are produced mainly from the Clupeidae fish, because meat of other fish species does not reach a desired level of ripeness in the acid-salt environment of fresh brine. Hence, this work presents an innovative idea of reusing brine including cathepsins and peptides for marinating cod, salmon, trout, and carp. The extent of marinades ripening improvement depended on fish resistance to the marinating process. The reused brine proved best in improving the ripening of fatty fish (salmon and trout), which were qualified to the first class of resistance to marinating. In the case of cod, the reuse of brine did not elicit a satisfactory improvement in meat ripening. Therefore cod was qualified to the second class of resistance. The reuse of brine resulted in decreased values of lipid oxidation indices (except for cod) and meat hardness, and in increased scores for overall sensory evaluation and total volatile bases nitrogen value.     

Structural Integrity of the A147T Polymorph of Mammalian TSPO

Ligands of the transmembrane protein TSPO are used for imaging of brain inflammation, but a common polymorphism in TSPO complicates their application to humans. Here we determined the three‐dimensional structure and side‐chain dynamics of the A147T polymorph of mammalian TSPO in complex with the first‐generation ligand PK11195. We show that A147T TSPO is able to retain the same structural and dynamic profile as the wild‐type protein and thus binds PK11195 with comparable affinity. Our study is important for the design of more potent diagnostic and therapeutic ligands of TSPO.     

Comparative tests of plasma-surfaced nickel layers with chromium and titanium carbides

This article presents the results of structural tests of composite coatings on a NiSi₂B alloy matrix containing carbides of Ti and Cr, which have been plasma surfaced from a powder mixture onto a low-alloyed steel substrate. The content and distribution of the strengthening phase in the matrix have been determined. It has been shown that the different nature of the interaction between Ti and Cr carbides and the liquid Ni alloy significantly affects the formation of composite surfacing layers as well as the distribution and content of strengthening phase particles in the matrix.     

Quenched steel welding

The aim of this research was to develop a process for welding BORON 27 type quenched steel, manufactured in Finland. The composition of a shielding gas mixture was selected by means of trials: 90% Ar, 5% CO₂, and 5% O₂. Joints were reproduced by this method, i.e. welded, quenched joints as well as unquenched welded joints, and were tested for quality. Tests included X-ray radiography, macroscopic testing, hardness tests, and tearing and bending resistance tests. The results of these tests were presented in the article.     

MODIFICATION OF EXTRACTION ABILITIES OF N,N,N'N'-TETRAALKYL-3,5-PYRIDINEDICARBOXAMIDE BY ITS ASSOCIATION WITH ALCOHOL

ABSTRACT

The extraction of copper with N,N,N'N'-tetrahexyl-3,5-pyridinedicarboxamide in the presence of the decanol and the co-association of the amide with alcohol were studied. Alcohol associates with the amide forming hydrogen bonds mainly with the oxygens of the carbonyl group without blocking the chemically active pyridine nitrogen. Hydration occurs in the same way. The effect of the alcohol on copper extraction is relatively small and weaker than the effect of chloride concentration.     

A kinetic-empirical model for particle size distribution evolution during pulverised fuel combustion

Particle size is an essential parameter in pulverised fuel (PF) combustion as many of the problems or further areas of development in these systems are strongly influenced by the fuel and ash size distribution. This is particularly true for dynamic processes like pollutant formation, corrosion, erosion, slagging and fouling and the related decrease of the combustion and boiler efficiency. The evolution of particle size distribution (PSD) is a complex interaction of various competing chemical and physical transformations. Char oxidation, devolatilization and fragmentation, etc. represent first line physical and chemical transformations which can amend the particle size in the radiation zone. The evolution of the PSD represents the convolution of all of these physical and chemical transformations, operating over the entire size distribution. As a consequence, it is difficult to extract the relative importance of all competing size altering processes from the experiments. Various models such as break-up, thermal stress, shrinking core, percolation and particle-population model have been developed by incorporating numerous ash transformation mechanisms to predict the particle size evolution during the pulverised fuel combustion. The present work describes an adaptation of the numerical kinetic-based particle-population balance for predicting particle size evolution during PF combustion developed by Dunn-Rankin and Mitchell. The model is further simplified analytically and validated against experimental results. Several empirical parameters derived from the experiments are incorporated into the model. The resulting simplified PSD evolution model shows good agreement with literature and experimental results, with maximum 10% absolute standard deviation.     

The influence of oxygen ambient annealing conditions on the quality of Al/SiO2/n-type 4H-SiC MOS structure

The effect of reoxidation process in O₂ on the electrical properties of metal-oxide-semiconductor (MOS) capacitors fabricated on n-type 4H-SiC (0 0 0 1) is investigated. All samples were oxidized in wet oxygen at temperature of 1175 °C. Reoxidation process was carried out on four of the five samples. Samples were annealed at temperature of 700 °C and 800 °C for different process times. The reoxidation process in oxygen improves the quality of the dielectric layer and the interface of Al/SiO₂/n-type 4H-SiC MOS structure. The best quality of the SiO₂/SiC interface can be achieved for the MOS structure annealed in O₂ at higher temperature (800 °C) for longer time. However, higher and more uniformly distributed values of breakdown voltage were obtained for MOS structures reoxidized at temperature of 700 °C.