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71.
Pulsed UV (PUV) is a novel UV irradiation system that is a non-mercury lamp-based alternative to currently used continuous-wave systems for water disinfection. PUV polychromatic irradiation disinfection efficiency was compared to that from continuous-wave monochromatic low-pressure (LP) and polychromatic medium-pressure (MP) UV systems, using two types of actinometry (ferrioxalate and iodide-iodate) and an absolute spectral emission method for fluence measurement. All three methods were in good agreement. Once accurate and reliable methods for fluence measurement were established, the inactivation of Escherichia coli and pathogen surrogates phage T4 and T7 were investigated under each technology. Inactivation was significantly faster using PUV irradiation compared to LP or MP UV lamps at equivalent fluence levels. A significant fraction of the enhanced PUV inactivation efficiency was due to wavelengths greater than 295 nm.  相似文献   
72.
Comparative glycan quantification has thus far been a challenging task due to the lack of sensitive and reproducible analytical techniques. We introduce here a combination of quantitative permethylation and isotope labeling of glycans as an approach (C-GlycoMAP) allowing precise comparison between different samples in a single MALDI-MS analysis. Samples are either methylated or deuteriomethylated prior to their mixing and mass spectrometric acquisitions. Comparative analyses are based on the ratio of the two isotopically distinct forms of the same glycan structure, thus allowing a direct absolute evaluation of the intensities of the two forms originating from two different biological samples (e.g., control and diseased). The direct comparison between the two forms eliminates a MALDI-MS low m/z bias commonly associated with this technique. These comparative analyses are highly reliable when the intensity ratios of the two forms lie between 0.125 and 6, an overall reproducibility better than 30% (RSD). The value of C-GlycoMAP is demonstrated here for N-glycans derived from human blood serum collected from a healthy individual and a breast cancer patient as well as for O-glycans derived from normal and cancer cell extracts.  相似文献   
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This paper presents innovative technology for the production of seamless Ni-Ti tubes using self-propagating high-temperature synthesis (SHS). The proposed production technology is a unique method which removes the need of forming operations, reduces machining processes, and at the same time it eliminates the negatives of production Ni-Ti alloys by conventional melting methods. The proposed process consists in SHS reaction in evacuated silica tube with the use of extremely high heating rate (over 300 K min?1).  相似文献   
75.
Trefftz-finite element method (Trefftz-FEM), adaptive cross approximation BEM (ACA BEM) and continuous source function method (CSFM) are used for the simulation of composites reinforced by short fibers (CRSF) with the aim of showing the possibilities of reducing the problem of complicated and important interactions in such composite materials.  相似文献   
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Method IEEE 841 is used to test endurance of insulation system of stators to 100% humidity at 40 ℃ for168 h. Insulation resistance after this test between phases or between phase and frame has not been lover as 5 × 10^6 Ohm. Some producers of motors use this method for determining quality of impregation resin. On such test insulation resistance between phases was lover as between phase and frame. Because between phases is only wire insulation impregnating resins on insulation resistance of insulation system an impregnating resin we observe influence of type of wires and after humidity test. With diagnostic of insulation, the state is dealt. We compare our impregnation resin with competitive impregnation resin. We made test on twisted coils prepared after STN IEC from two parallel wires. In this test, we succeed in demonstrating that the main influence on insulation resistance of insulation system wire and impregnation resin has insulation of wire. Impregnation resin has influenced on data dispersion.  相似文献   
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Textural changes in six bituminous coals (from 16.3 to 31.4% VM daf), after reduction with lithium in ethylenediamine at 373 K, have been established according to N2 isotherms at 78 K and C02 isotherms at 298 K. Changes in pore volume were determined from the real and apparent densities and from the volume filling of micropores. Macroscopic changes on the grain surfaces were determined by means of the scanning electron microscope. It appears from these experiments that an initial increase in total porosity is caused by the action of ethylenediamine alone, while the final changes, primarily in the meso- and macropores (similar to disturbances of the external grain surface), result from the reduction process. The location of the added ethylenediamine in the bulk of the reduced coal has also been considered.  相似文献   
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