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Materials for ophthalmic coatings in PVD – coating equipments In our days we cannot have an isolated view only at the coatings for organic lenses. We need to analyse the interaction of substrates, hardcoats and layerdesigns to deliver a longlife – quality of the complete complex “eyeglases”. Special in the field of organic substrates we could observe in the last years an enormous change. The push to deliver more and more thinner and lighter lenses, produces materials with higher indices. The result from this problem is not the adaptation of the antireflection desin at the substrate index but the adaption at the mechanical and thermal properties of these substrates. The caoting labs influence at the complete system is more or less reduced only by the antireflection system. The substrate‐ and hardcoat material could be influenced only by the “world player” for ophthalmic systems. All the small and middle size coating labs worldwide must buy the substrates‐ and the hardcoat materials and have to accept the quality. The only exertion of influence is in the selection of film materials for the AR‐coating and the process technology. The right choise of coating material in quality, form and costs is crucial for a high quality AR‐ coating. A multitude of factors must be considered for the selection of the adequate material. 相似文献
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A mathematical simulation model is presented describing the discharge process of metal hydrides. The model is applied to FeTi-single tube and multiple tube beds and the results are compared directly to the results of experimental investigations. Furthermore, the most important engine parameters, with respect to the operation with metal hydride stored hydrogen, were determined for the nonsteady FTP 72-driving cycle. Minimum hydride quantities, necessary to supply the engine with hydrogen during the warm-up phase, were calculated for different starting temperatures and initial hydrogen contents of the bed. 相似文献
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K Lenz S N Mahnik N Weissenbacher R M Mader P Krenn S Hann G Koellensperger M Uhl S Knasmüller F Ferk W Bursch M Fuerhacker 《Water science and technology》2007,56(12):141-149
Cytostatic agents are applied in cancer therapy and subsequently excreted into hospital wastewater. As these substances are known to be carcinogenic, mutagenic and toxic for reproduction, they should be removed from wastewater at their source of origin.In this study the fate and effects of the cancerostatic platinum compounds (CPC) cisplatin, carboplatin, oxaliplatin, 5-fluorouracil (5-FU) and the anthracyclines doxorubicin, daunorubicin and epirubicin were investigated in hospital wastewater. Wastewater from the in-patient treatment ward of a hospital in Vienna was collected and monitored for the occurrence of the selected drugs. A calculation model was established to spot the correlation between administered dosage and measured concentrations. To investigate the fate of the selected substances during wastewater treatment, the oncologic wastewater was treated in a pilot membrane bioreactor system (MBR) and in downstream advanced wastewater treatment processes (adsorption to activated carbon and UV-treatment). Genotoxic effects of the oncologic wastewater were assessed before and after wastewater treatment followed by a risk assessment.Monitoring concentrations of the selected cytostatics in the oncologic wastewater were in line with calculated concentrations. Due to different mechanisms (adsorption, biodegradation) in the MBR-system 5 - FU and the anthracyclines were removed < LOD, whereas CPC were removed by 60%. In parallel, genotoxic effects could be reduced significantly by the MBR-system. The risk for humans, the aquatic and terrestrial environment by hospital wastewater containing cytostatic drugs was classified as small in a preliminary risk assessment. 相似文献
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The susceptibility of Mycobacterium tuberculosis and Mycobacterium avium-intracellulare to the disinfections used for spillage and heat sensitive instruments has received much attention in recent years. The use of clinical isolates of M. tuberculosis and M. avium-intracellulare as test organisms is considered unsuitable for standard tests due to their hazardous nature (category 3 pathogens and slow growth rates). This has led to much debate in standards committees on the selection and use of a possible surrogate which would be safer and more practical to use and yet mimic the susceptibility of clinical isolates. This study compared the susceptibility of one possible surrogate Mycobacterium terrae NCTC 10856, with that of clinical isolates of M. tuberculosis H37 Rv and M. avium-intracellulare using a quantitative suspension test. The instrument and environmental disinfectants tested were a chlorine-releasing agent, sodium dichloroisocyanyurate (NaDCC) at 1000 ppm and 10,000 ppm av. Cl, chlorine dioxide at 1100 ppm av. ClO2 (Tristel, HayMan MediChem), 0.35% peracetic acid (NuCidex, Johnson & Johnson), 70% industrial methylated spirit (IMS), 2% alkaline glutaraldehyde (Asep, Galen), 10% succine dialdehyde and formaldehyde mixture (Gigasept, Schulke and Mayr). Results showed that the clinical isolate of M. avium-intracellulare was the most resistant of the three test organisms. M. terrae, which is not a category 3 pathogen, was slightly more resistant than M. tuberculosis and this would appear to be a suitable surrogate for establishing tuberculocidal activity. However, with an increase in the clinical significance of M. avium-intracellulare, particularly in human immunodeficiency virus (HIV) and immunocompromised patients, a more resistant surrogate is required. In the absence of such a surrogate, testing with M. avium-intracellulare in a clinical laboratory equipped for handling category 3 pathogens is still advised to establish mycobactericidal activity. 相似文献
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The diagnostic value of monitoring human cytomegalovirus (HCMV) late pp67 mRNA expression by nucleic acid sequence-based amplification (NASBA) after renal-allograft transplantation was evaluated. RNAs were isolated from 489 whole-blood specimens of 42 patients for the specific amplification of the late pp67 (UL65) mRNA. NASBA results were compared to results from the pp65 antigenemia assay, virus isolation by cell culture, and serology. The sensitivity value for NASBA proved to be higher than that for the antigenemia assay (50 versus 35%) for the detection of HCMV infection, while the sensitivity values of cell culture and NASBA were comparable (54 and 50%, respectively). NASBA detected the onset of HCMV infection simultaneously with cell culture and the antigenemia assay. Both the antigenemia assay and NASBA are very specific (100%) and highly predictive (100%) for the onset of HCMV infection. Antiviral therapy with ganciclovir resulted in negative results for cell culture, the antigenemia assay, and NASBA. In conclusion, monitoring HCMV pp67 mRNA expression by NASBA is a highly specific method for the detection of HCMV infection in renal-allograft recipients and is more sensitive than the antigenemia assay. Furthermore, NASBA can be used to monitor the progression of HCMV infections and the effect of antiviral therapy on viral activity. 相似文献
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