The use of hybrid anaerobic solid–liquid (HASL) system for the treatment of lipid‐containing food waste

The hybrid anaerobic solid–liquid (HASL) system was a modified two‐phase anaerobic digester developed for bioconversion of food waste. The aim of this study was to estimate the feasibility of the HASL system for the treatment of food waste with a high content of lipids. The presence of lipids in food waste increased the energy value of nutrients but could inhibit growth of methanogens. The positive effect of lipids on the performance of anaerobic digestion dominated when the contents of lipids were in the range from 20 to 30% of total solids of food waste. Lipid contents of 40% diminished the production of volatile fatty acids in the acidogenic reactor as well as biogas production and the concentration of total bacteria and methanogens in the methanogenic reactor. Therefore, the HASL system can be used for the treatment of lipid‐containing food wastes if the lipid content is below 40% of total solids. Copyright © 2005 Society of Chemical Industry     

Coherent anti-Stokes Raman scattering enhancement of thymine adsorbed on graphene oxide

Coherent anti-Stokes Raman scattering (CARS) of carbon nanostructures, namely, highly oriented pyrolytic graphite, graphene nanoplatelets, graphene oxide, and multiwall carbon nanotubes as well CARS spectra of thymine (Thy) molecules adsorbed on graphene oxide were studied. The spectra of the samples were compared with spontaneous Raman scattering (RS) spectra. The CARS spectra of Thy adsorbed on graphene oxide are characterized by shifts of the main bands in comparison with RS. The CARS spectra of the initial nanocarbons are definitely different: for all investigated materials, there is a redistribution of D- and G-mode intensities, significant shift of their frequencies (more than 20 cm^-1), and appearance of new modes about 1,400 and 1,500 cm^-1. The D band in CARS spectra is less changed than the G band; there is an absence of 2D-mode at 2,600 cm^-1 for graphene and appearance of intensive modes of the second order between 2,400 and 3,000 cm^-1. Multiphonon processes in graphene under many photon excitations seem to be responsible for the features of the CARS spectra. We found an enhancement of the CARS signal from thymine adsorbed on graphene oxide with maximum enhancement factor about 10⁵. The probable mechanism of CARS enhancement is discussed.     

An adaptive learning algorithm for a wavelet neural network

Abstract: An optimal online learning algorithm of a wavelet neural network is proposed. The algorithm provides not only the tuning of synaptic weights in real time, but also the tuning of dilation and translation factors of daughter wavelets. The algorithm has both tracking and smoothing properties, so the wavelet networks trained with this algorithm can be efficiently used for prediction, filtering, compression and classification of various non-stationary noisy signals.     

Dynamic mechanical study of filled semi-interpenetrating polymer networks: Influence of γ-Fe2O3 on microphase structure

The preparation of filled two-component semi-interpenetrating polymer networks (semi-IPNs) is described and the results of an investigation of their morphology by means of dynamic mechanical spectroscopy are considered. The influence of an active dispersed filler (γ-Fe₂O₃) on the semi-IPNs phase structure is studied. A comparison is made between filled and unfilled semi-IPNs consisting of compatible or incompatible polymers. In the case of a semi-IPN of compatible polymers, the introduction of γ-Fe₂O₃ was observed to cause phase separation. With a two-phase semi-IPN the introduction of the filler enhanced the phase separation. The presence of two distinct peaks (the dynamic glass transition temperatures) corresponding to those of the two initial homopolymers shows the semi-IPN to have a two-phase structure.     

Characterization of Nonmetallic Inclusions in 18CrNiMo7-6

Metallurgical and Materials Transactions B - The detrimental effect of nonmetallic inclusions (NMIs) in steels on, e.g., fatigue lifetime is well known. In order to increase the durability and...     

The formation and performance of auxetic textiles. Part I: theoretical and technical considerations

Auxetic textiles belong to a class of extraordinary materials that become fatter when stretched. Sustained efforts to fabricate auxetic fabric structures are limited. Indeed, several geometrical configurations have been previously proposed but none has been engineered into functional auxetic textile fabrics. The use of auxetic materials has been limited because of problems with deploying them in their fabricated forms. Our thrust in this research is to combine our knowledge of geometry and fabric structural characteristics to engineer auxetic textiles and to determine the properties of such auxetic textile fabrics. In this paper, we have presented the technique we developed for producing several knit structures in which filling yarn inlays are used to effect compound repeating units. In these productions, the chain is used as a base structure and a minimum of two guide bars and maximum of six guide bars are deployed to produce such warp knit auxetic fabrics.     

Influence of Dryer Type on Surface Characteristics of Milk Powders

Reconstituted milk powders (skim milk, whole milk, and milk protein concentrate powders) were spray dried using research-scale (laboratory- and pilot-scale) spray dryers to investigate the influence of type on the dryer on the surface composition (protein, fat, lactose) and morphological characteristics (size and surface structure) of the powder particles. Milk powders produced by these research-scale dryers were compared to commercially produced and freeze-dried powders. The powders produced by the laboratory- and pilot-scale dryers were significantly different from the commercially dried powders in both surface composition and morphology. The milk powders produced by laboratory- and pilot-scale dryers provided reproducible results with similar surface morphologies between dryer types, despite varying surface compositions. The surface composition of the freeze-dried powder was also significantly different from than that of the spray-dried powders. The freeze-dried skim milk powder (SMP) was similar in surface protein to its bulk protein composition, indicating relative homogeneity of particle composition of the freeze-dried powder.     

Tailoring the molecular and thermo–mechanical properties of kraft lignin by ultrafiltration

This study has shown that ultrafiltration allows the selective extraction from industrial black liquors of lignin fraction with specific thermo‐mechanical properties, which can be matched to the intended end uses. Ultrafiltration resulted in the efficient fractionation of kraft lignin according to its molecular weight, with an accumulation of sulfur‐containing compounds in the low‐molecular weight fractions. The obtained lignin samples had a varying quantities of functional groups, which correlated with their molecular weight with decreased molecular size, the lignin fractions had a higher amount of phenolic hydroxyl groups and fewer aliphatic hydroxyl groups. Depending on the molecular weight, glass‐transition temperatures (T_g) between 70 and 170°C were obtained for lignin samples isolated from the same batch of black liquor, a tendency confirmed by two independent methods, DSC, and dynamic rheology (DMA). The Fox–Flory equation adequately described the relationship between the number average molecular masses (M_n) and T_g's‐irrespective of the method applied. DMA showed that low‐molecular‐weight lignin exhibits a good flow behavior as well as high‐temperature crosslinking capability. Unfractionated and high molecular weight lignin (M_w >5 kDa), on the other hand, do not soften sufficiently and may require additional modifications for use in thermal processings where melt‐flow is required as the first step. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40799.     

Polymer resins with epoxy end groups obtained from hydrocarbon pyrolysis C9 fraction

Polymer resins with epoxy groups (PREGs) are synthesized by radical copolymerization of hydrocarbon pyrolysis C₉ fraction using 1,2-epoxy-3-tert-butylperoxypropane as the initiator or by copolymerization of the ED-20 epoxy resin modified by tert-butyl hydroperoxide. The effect of the initiator nature and quantity, temperature and reaction time on the yield and characteristic of PREGs are examined. The structure of synthesized products is established by chemical methods and IR spectroscopy. The structurization of ED-22 epoxy resin is studied in the presence of polyethylenamine using 10 and 25 mass% of PREG.     

Immunohistochemical analysis of S6K1 and S6K2 expression in human breast tumors

AIM: To express recombinant S6K2 in baculovirus expression system; to purify large quantities of recombinant S6K2 for biochemical studies; to generate and characterise specific MABs against recombinant S6K2; to study the patterns S6K1 and S6K2 expression and subcellular localization in normal, benign and malignant breast tissues. METHODS: Recombinant baculovirus, expressing wild type S6K2 was generated using Bac-to-Bac system (Invitrogen); recombinant S6K was purified from infected Sf9 cells using affinity purification approach; monoclonal antibodies against recombinant S6K2 were generated; the specificity of generated MABs towards recombinant and endogenous S6K2 were examined by ELISA, Western blotting, immunoprecipitation and immuhohistochemical staining; immunohistochemical detection of S6K1 and S6K2 in human breast tissues was performed using specific monoclonal antibodies towards S6K1 and S6K2. RESULTS: Large amounts of enzymatically active S6K2 were purified using baculovirus expression system; highly purified preparations of S6K2 were used to generate and characterize anti-S6K2 MABs; elevated levels of S6K1 and S6K2 were found in breast tumors when compared to normal breast tissues; S6K2 is frequently localized in the nuclei of adenocarcinoma tissues, but rarely in fibroadenoma or "normal" breast tissues. CONCLUSION: Production of recombinant S6K2 in large amount and generation of specific monoclonal antibodies towards S6K2 has provided us with excellent tools to study the function and regulation of this important signalling molecule in normal and cancer cells. Immunnohistochemical analysis of S6K1 and S6K2 expression in normal and malignant breast clearly indicates that both kinases are overexpressed in breast tumors, when compared to "normal" tissues. The retention of S6K2 in the nuclei of malignant cells may be caused by disregulation of nucleocytoplasmic shuttling and could subsequently affect cell growth and proliferation.