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1.
A series of long-chain quaternary ammonium halogen esters (UKK-chemicals), quaternary dimethyl tallow epoxypropyl ammonium
halogens (EPK1), quaternary ditallow methyl epoxypropyl ammonium halogens (EPK2), and EPK2 oligomers (EPK2P) were synthesized.
At acidic, neutral, or slightly basic conditions, EPK1-, EPK2-, EPK2P-, and UKK-chemicals operate as cationic chemicals. They
can be used, for example, as stock sizings, surface sizings, or fixatives. Stock sizing, surface sizing, and fixative experiments
indicate that EPK1-, EPK2-, EPK2P-, and UKK-chemicals function at least as well as or better than the corresponding synthetic
chemicals used in papermaking. 相似文献
2.
The aim of this study was to examine the response of the autonomic nervous system in younger (mean age 31 yrs, n=14) and older (mean age 54 yrs, n=14) healthy female teachers during work periods of perceived high and low stress. In the younger participants, heart rate, cortisol excretion rate and psychosomatic symptoms were significantly higher during the high work stress period. The older participants experienced no decrease in their heart rate and cortisol excretion during the low stress period and they exhibited no significant decrease in blood pressure after the work in the evening during both periods. It may be concluded that the recovery from the stress in the older teachers was insufficient particularly in view of their elevated diastolic blood pressure during the low work stress period. Ergonomic and individually tailored measures in terms of work time control, specific relaxation techniques, and a part-time retirement may improve the stress management of older teachers. 相似文献
3.
Song Fu Osmo Kauppila Matti Mottonen 《The International Journal of Advanced Manufacturing Technology》2011,57(9-12):1079-1086
In 100% inspection, measurement errors are unavoidable. Due to these errors, acceptable products are sometimes rejected (overkill) and defective products are accepted (escape). Overkill increases production costs, while escape is a source of customer dissatisfaction. This study presents a model for calculating overkill and escape rates using process and measurement system performance data. A practical example of applying the model is also presented to calculate gage reproducibility and repeatability requirements for different production settings. Industrial managers and quality engineers can utilize the results of this study to calculate escape and overkill rates of their production systems, and to assess and improve their processes. 相似文献
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Ohne Zusammenfassung 相似文献
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Helvi M. Vidgren Jyrki J. Ågren Ursula Schwab Tiina Rissanen Osmo Hänninen Matti I. J. Uusitupa 《Lipids》1997,32(7):697-705
The effects of n-3 fatty acid supplementation in the form of fresh fish, fish oil, and docosahexaenoic acid (DHA) oil on the
fatty acid composition of plasma lipid fractions, and platelets and erythrocyte membranes of young healthy male students were
examined. Altogether 59 subjects (aged 19–32 yr, body mass index 16.8–31.3 kg/m2) were randomized into the following diet groups: (i) control group; (ii) fish diet group eating fish meals five times per
week [0.38±0.04 g eicosapentaenoic acid (EPA) and 0.67±0.09 g DHA per day]; (iii) DHA oil group taking algae-derived DHA oil
capsules (1.68 g/d DHA oil group taking algae-derived DHA oil capsules (1.68 g/d DHA in triglyceride form); and (iv) fish
oil group (1.33 g EPA and 0.95 g DHA/d as free fatty acids) for 14 wk. The fatty acid composition of plasma lipids, platelets,
and erythrocyte membranes was analyzed by gas chromatography. The subjects kept 4-d food records four times during the study
to estimate the intake of nutrients. In the fish diet, in DHA oil, and in fish oil groups, the amounts of n-3 fatty acids
increased and those of n-6 fatty acids decreased significantly in plasma lipid fractions and in platelets and erythrocyte
membranes. A positive relationship was shown between the total n-3 polyunsaturated fatty acids (PUFA) and EPA and DHA intake
and the increase in total n-3 PUFA and EPA and DHA in all lipid fractions analyzed. DHA was preferentially incorporated into
phospholipid (PL) and triglyceride (TG) and there was very little uptake in cholesterol ester (CE), while EPA was preferentially
incorporated into PL and CE. The proportion of EPA in plasma lipids and platelets and erythrocyte membranes increased also
by DHA supplementation, and the proportion of linoleic acid increased in platelets and erythrocyte membranes in the DHA oil
group as well. These results suggest retroconversion of DHA to EPA and that DHA also interferes with linoleic acid metabolism. 相似文献
6.
The curing process of unsaturated polyester resins, vinyl ester resins, and gel coats was studied by using a process Raman spectrometer, equipped with a remote fiber‐optic probe. The resins were cured and Raman spectra were recorded during the curing reaction. The spectral changes were identified and, from the intensities, the cure process could be monitored. Gel times given by the resin suppliers correlated well with the Raman results. It could also be seen that the curing process continues for a long time, up to several weeks. Postcuring will finally complete the curing process. White and lightly colored gel coats could easily be monitored by Raman spectroscopy, but fluorescent problems were encountered with heavily colored pigments. The curing of laminates containing 50–70 wt % glass fiber mat could also be followed by Raman spectroscopy. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1285–1292, 2004 相似文献
7.
Jarkko J. HeikkinenLiisa Kivimäki Vesa P. HytönenMarkku S. Kulomaa Osmo E.O. Hormi 《Thin solid films》2012,520(6):1934-1937
An approach for creating a flexible and macroporous silsesquioxane film using phase separation method is described. The porous film was prepared by a simple coating method where sol-gel solution containing polyacrylic acid (PAA) and 1,6-bis(trimethoxysilyl)hexane in water was applied on boehmite silica coated polymethylmethacrylate (PMMA) film. After drying, the water soluble PAA template was removed by washing the film with water revealing the porous film. With certain ratios of PAA and water, fully co-continuous pore system with open surface was obtained. Porous films with 3-4 μm thickness were found to be highly flexible. The biocompatibility of the porous film was tested by immobilizing a high affinity biotin-binding chimeric avidin (ChiAVD(I117Y)) into the porous matrix The porous film was found to adsorb higher amounts of functional chimeric avidin compared to the pure PMMA film or a boehmite silica coated PMMA film. 相似文献
8.
Kärkkäinen AH Tamkin JM Rogers JD Neal DR Hormi OE Jabbour GE Rantala JT Descour MR 《Applied optics》2002,41(19):3988-3998
Direct photolithographic deforming of hybrid glass films is used to fabricate optical structures. The structure is fabricated in polyethylene-oxide-acrylate modified hybrid glass films with (1) binary and gray-scale photomasks using a mercury UV-lamp exposure and (2) maskless UV-laser patterning. Fabrication of isolated lenslets, lens arrays, and gratings is presented, including the associated exposure patterns. The hybrid glass material yields light-induced deformation peak-to-valley (p.v.) heights up to 12.8 microm with mercury UV-lamp exposure and p.v. deformation heights up to 6.8 microm with 365-nm UV-laser exposure. The fabricated lenslets' surface data are presented as Zernike-polynomial fit coefficients. Material synthesis and processing-related aspects are examined to understand and control the material's deformation under exposure. The hybrid glass material exhibits a maximum spectral extinction coefficient of 1.6 x 10(-3) microm(-1) at wavelengths ranging from 450 to 2,200 nm and has a refractive index of 1.52 at 632.8 nm. The fabricated structures exhibit rms surface roughness between 1 and 5 nm. 相似文献
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