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1.
Catalysis Letters - Industrial Cu/ZnO/Al2O3 or novel rate catalysts, prepared with a photochemical deposition method, were studied under functional CH3OH synthesis conditions at the set temperature...  相似文献   
2.
Polymer cross-linked matrices based on polyacrylamide (PAA) and β-cyclodextrin-pseudorotaxane have been designed. The structure and properties of the objects synthesized were confirmed and studied by a series of methods, involving ultraviolet-, Fourier transform infrared-spectroscopy, thermal mass spectrometry, DSC, X-ray diffraction analysis (WAXS and SAXS). Desorption kinetics (especially significant slowing of desorption process) of some drugs, like metoprolol succinate and loratadine from obtained polymer matrices is shown to be optimal with 10 wt% β-CD-pseudorotaxane in their structure.  相似文献   
3.
Microstructural development during transient liquid-phase bonding of cast polycrystalline near-stoichiometric NiAl (B2 compound, -phase) was investigated using cross-sectional transmission electron microscopy. Bonds made using Ni-4.5 wt % Si-3.2 wt % B (AWS designation BNi-3) interlayers in the form of melt-spun foils were studied. Microstructural changes in the joint region and surrounding substrates were examined as a function of holding time at temperatures of 1065 and 1150°C. The transformation of the substrate -phase to L10-type martensite due to aluminium transfer to the joint has been discussed, and the formation of L12 type ( structure) layers at the joint-substrate interfaces considered. The nature of the isothermal solidification process has also been discussed and the changes, with holding time at the bonding temperature, in the character of the residual eutectic examined. The formation of M23X6-type borides within both the joint and surrounding substrates was also considered.  相似文献   
4.
This article looks at the current working profile of blast furnaces at the Krivorozhstal’ combine. The profiles were formed during a period in which the operation of the furnaces was not forced, the supply of raw materials was inconsistent, and furnace output was irregular. The results of studies show a need for closer monitoring of the cooling system and the parameters of the profile of furnaces in the period before a scheduled maintenance. Timely action needs to be taken to eliminate problems in furnace operation caused by the presence of thick slag crusts. It is shown that the variable slag-formation conditions about the furnace circumference are due mainly to factors that affect the smelting operation from below — nonuniform blast delivery and a nonuniform distribution of the blast among the tuyeres, as well as local differences in drainage and the movement of coke in the hearth. These differences depend on the location of the iron notches. It is noted that the aggressiveness of alkalis and zinc in blast-furnace shafts has increased. An efficient furnace profile can be maintained by limiting the entry of aggressive compounds into the furnace and washing its interior to remove such compounds from the circulation loop.  相似文献   
5.
Data of an experimental investigation of the hydraulic resistance of the abrupt contractions and expansions of round pipes to the turbulent flow of polyacrylamide aqueous solutions are presented. An increase and a decrease in the head loss have been revealed. An explanation of the results obtained is given.  相似文献   
6.
The article studies mass transfer from the surface of a sphere when a liquid flows around it under conditions of Reynolds numbers 103?5g105, and also when a cavitation cavern forms behind the sphere.  相似文献   
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OBJECTIVE: To describe how the tobacco industry attempted to trivialise the health risks of second hand smoke (SHS) by both questioning the science of risk assessment of low dose exposure to other environmental toxins, and by comparing SHS to such substances about which debate might still exist. METHODS: Analysis of tobacco industry documents made public as part of the settlement of litigation in the USA (Minnesota trial and the Master Settlement Agreement) and available on the internet. Search terms included: risk assessment, low dose exposure, and the names of key players and organisations. RESULTS/CONCLUSION: The tobacco industry developed a well coordinated, multi-pronged strategy to create doubt about research on exposure to SHS by trying to link it to the broader discussion of risk assessment of low doses of a number of toxins whose disease burden may still be a matter of scientific debate, thus trying to make SHS their equivalent; and by attempting, through third party organisations and persons, to impugn the agencies using risk assessment to establish SHS as a hazard.  相似文献   
10.
Hydrated nickel oxide NiOxHy films were deposited onto indium tin oxide (ITO) coated glass by two methods (i) colloidal precipitation and (ii) anodic electrodeposition. The electrochromic properties of hydrated nickel oxide films were studied by transmittance measurements (UV/VIS/NIR), and Fourier transform infrared reflectance spectroscopy as a function of the key deposition parameters. The solar transmittance was calculated for films switched in both bleached and coloured states. The best results were achieved for films produced by anodic electrodeposition from stable solutions with solar transmittance Ts(bleached) = 0.82 and Ts(coloured) = 0.22. Corresponding optimum values for the films produced by colloidal precipitation were solar transmittance Ts(bleached = 0.82 and Ts(coloured) = 0.47. Fourier transform spectrophotometry was used for elucidating changes in hydration, hydroxylation and for the characterization of structural characteristics in the bleached and coloured states. It was found that free OH stretching vibration at 3647 cm−1 corresponds to Ni(OH)2 for both anodic and colloidal deposited films in the reduced (bleached) state. In the oxidised state hydrogen bonded OH at 3360 cm−1 is observed.  相似文献   
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