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[en] As a result of the reaction of tryptophan with copper (II) chloride, a complex of copper tryptophan ate was obtained. The composition of the complex was studied by elemental, thermal, Χ-ray phase analysis, IR, and UV spectroscopy. The anti radical activity of the complex was studied on irradiated wheat seeds. It was revealed that the treatment of wheat seeds before irradiation with an aqueous solution of complex leads to normalization of the biosynthesis of photosynthetic pigments.
[en] Full text: The technical and economic assessment of process of thermo-chemical decomposition of biomass in the processes of transformation of it in power-consuming energy/carriers by the use of the concentrated gel of sun radiation, has been considered
[en] The present investigation deals with the study of untreated and alkali treated natural fibers extracted from the stem of Catharanthus roseus. The physical, chemical, crystallinity, mechanical, wettability, thermal, and surface characteristics were analyzed for untreated and alkali treated Catharanthus roseus fibers (CRFs). The results showed that chemical treatment removed excess amorphous contents such as hemicellulose, lignin and wax contents thereby there was an enhancement in tensile strength, crystalline index, and surface roughness. The char residue upon thermogravimetric analysis got increased from 25.2% to 39.6% for untreated and alkali treated CRFs respectively. The alkali treated CRF showed lesser contact angle which proved its improved wettability in the liquid phase. Thus the improvement in the characteristics of the alkali treated CRF can make it useful for developing lightweight polymer composites. (paper)
[en] Full text: The new organic ligands -N-(5-clorasalicylidine)-β-athanol (HL'1), N(-5-bromosalicyliden)-β-alanine (H2L3), N(-2-hydroxy-5-bromobenzyl)-β-alanine (H2L4), N-(5-bromosalicylidene) qlycibe (H2L5) have been obtained. The new lanthanide complexes (Y, La,Ce,Nd,Sm,Er,Lu) with N-(2-hyroxy-5-brombenzyl)-β-alanine (H2L4) have been prepared and studied. The elemental analyses, IR-spectra and thermo gravimetric data point out on the following composition of the obtained compounds: Ln(L)(X)(H2O)n (where L=N-(2-hydroxy-5-brombenzil)-β-alanine (H2L4), X=CH3COO-, NO3-, Br-, n=3,4). IR spectra's indicate on bi- or polynyclear structure of complexes
[en] Highlights: ► A process combined pyrolysis and acid immersion was proposed to dispose waste LCDs. ► This process maximally recovered valuable resources while treating the waste LCDs. ► Valuable product was obtained by applying the pyrolysis of polarizing film from LCD. ► The indium recovery was optimized by using response surface methodology. ► A polynomial equation was obtained that well predicted the indium recovery process. -- Abstract: A process combined pyrolysis and acid immersion was proposed in this study to dispose the hazardous liquid crystal display (LCD) waste for recovering valuable resources. The thermogravimetric (TG) analysis and fixed bed pyrolysis were investigated for the polarizing film that was separated from LCD. The results suggested the liquid product mainly contained acids, esters and aromatics should be upgraded such as hydrotreating process before used as industrial feedstock or fuel source. The gaseous product mainly consisted of H2, CO, CO2 and CH4 can be used as a valuable fuel. The sulfuric acid immersion experiments were studied for recovering indium from the LCD glass after stripping the polarizing film. Central composite design (CCD) under response surface methodology (RSM) was used to optimize the acid immersion process and the results indicated the indium recovery can be fitted based on the actual value to a polynomial quadratic equation and the temperature was more essential factor than time and acid concentration in the studied ranges. The optimum processing condition was obtained with time 42.2 min, temperature 65.6 °C and acid concentration 0.6 mol/L. Under the optimal conditions, the indium recovery was close to 100%
[en] Thermogravimetric analysis of a solid sample with mass spectrometry (TGA-MS) of the evolved gas is used in the destructive examination (DE) portion of the Integrated Surveillance Program to quantify the moisture content of the material stored in a 3013 container. As with any measurement determined from a small sample, the collection, storage, transportation, and handling of the sample can affect its ability to represent the properties of the bulk material. During the course of the DE program, questions have periodically arisen concerning the ability of the moisture sample to reflect reliably the actual moisture content of the entire material stored in the 3013 container. Most concerns are related to the ability to collect a representative sample and to preserve the moisture content of the sample between collection and analysis. Recent delays in analysis caused by maintenance issues with the TGA-MS instrument presented a unique opportunity to document and quantify the effects various factors have on the TGA-MS moisture measurement. This report will use recent data to document the effects that current sample collection and handling practices have on the TGA-MS moisture measurement. Some suggestions will be made which could improve the current sample collection and handling practices for the TGA-MS moisture measurement so that the analytical results more accurately reflect the moisture content of the material stored in the 3013 container.
[en] Dy(Is2MeTSC)3 [Is2MeTSC= isatin 2-methyl-3-thiosemicarbazone] was synthesized by condensation method. The compounds were structurally characterized by elemental analysis, FT-IR, UV-Vis, TGA and X-ray crystallographic study. The results of the elemental analyses for the compounds were in good agreement with the theoretical values. The X-ray crystallographic structures for Is2MTSC showed that in the solid state, the compound existed in the thione form, where the C=S bond length was shorter than a single bond C-S, which was 1.82 Angstrom. Is2MTSC adopted an orthorhombic system, a = 14.3434(9), b = 8.4242(5), c = 17.8518(11) Angstrom and Z = 8. The FT-IR spectral data implied a tri-dentate bonding of Is2MeTSC to Dy(III) ion through carbonyl oxygen, azomethine nitrogen and thiocarbonyl sulfur. (author)
[en] Highlights: ► We developed a butt welding apparatus for doubled walled Polyethylene pipe. ► We design the welding process by analyzing thermal behaviors of the material. ► We performed the welding and tested the welded structural performances. ► We also applied the same technology to PVC pipes. ► We verified the butt welding was successful and effective for the pipes with irregular sections. -- Abstract: In this study, mechanical analyses of a butt welding technology for joining Polyethylene pipe are presented. The pipe had unique structure with double wall, and its section topology was not flat. For an effective repair of leakage and replacements of the pipe, the butt welding technology was developed and tested. For the material characterizations, thermodynamic analyses such as thermal gravimetric analysis and differential scanning calorimetry were performed. Based on the test results, the process temperature and time were determined to ensure safe joining of the pipes using a hot plate apparatus. The welding process was carefully monitored by measuring the temperature. Then, the joined pipes were tested by various methods to evaluate the quality. The analyses results showed the detail process mechanism during the joining process, and the test results demonstrated the successful application of the technology to the sewage pipe repairs.