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971.
This paper describes an experimental study on a method of removing aerosol particles from air by condensing heated and humidified air. In the experiment, air, including aerosol particles, is circulated by a fan in a closed clean room system consisting of a closed vessel, a humidifier, two condensers, and an after-heater. The concentration of aerosol particles at the inlet of the closed vessel, the relative humidity, and the temperature in the system are measured for several humidification and condensation conditions. We find that the removal rate of aerosol particles in air increases when the mass flow rate of the condensate increases, by means of enlarging the temperature difference between the heating water in the humidifier and the cooling water in the condensers. We also show that this method is more effective when the temperature level in the humidifier is increased. The aerosol particle removal mechanism of this method is considered to be related to the generation of mist using aerosol particles as nuclei, inertia trapping, and the suction effect of condensation. © 1998 Scripta Technica. Heat Trans Jpn Res, 26(6): 398–409, 1997 相似文献
972.
A nonequilibrium condition is often used in plasma processing. A silent discharge is one of the simplest methods for realizing this condition. In the case that a square pulsed voltage has been applied, this method enables high-energy input into a reaction field. However, the mechanism for this has never been clarified. In this study, an experiment on pulsed silent discharge has been carried out using a discharge tube with a corona electrode system and oxygen gas. The characteristics of this discharge were then investigated, and its mechanism estimated. As a result, it was clarified that the pulsed silent discharge, especially in the case of a developing positive streamer, has highly nonequilibrium characteristics. © 1998 Scripta Technica. Heat Trans Jpn Res, 26(4): 207–218, 1997 相似文献
973.
Malinie Senanayake Errol R Jansz Ken A Buckle 《Journal of the science of food and agriculture》1997,74(1):42-48
Four mixing intervals (6, 12, 18 and 24 h) were compared with special reference to three selected cacao varieties from two locations of Sri Lanka. Cocoa beans were fermented for 6 days by using the ‘sweat box’ fermentation method. Irrespective of location and variety, product prepared by using all mixing intervals were significantly different with variations in temperature as well as degree of fermentation. Frequent mixing (at 6 and 12 h) produced a higher number of well-fermented beans than other treatments. When practical aspects of fermentation in both small and large scale contexts are considered, mixing at 12 h intervals for 6 days can be recommended as the most suitable treatment for three varieties tested from two locations. © 1997 SCI. 相似文献
974.
Miwa Fujihara Tadahiko Shien Kazuhiko Shien Ken Suzawa Tatsuaki Takeda Yidan Zhu Tomoka Mamori Yusuke Otani Ryo Yoshioka Maya Uno Yoko Suzuki Yuko Abe Minami Hatono Takahiro Tsukioki Yuko Takahashi Mariko Kochi Takayuki Iwamoto Naruto Taira Hiroyoshi Doihara Shinichi Toyooka 《International journal of molecular sciences》2021,22(23)
Trastuzumab-emtansine (T-DM1) is a therapeutic agent molecularly targeting human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC), and it is especially effective for MBC with resistance to trastuzumab. Although several reports have described T-DM1 resistance, few have examined the mechanism underlying T-DM1 resistance after the development of acquired resistance to trastuzumab. We previously reported that YES1, a member of the Src family, plays an important role in acquired resistance to trastuzumab in HER2-amplified breast cancer cells. We newly established a trastuzumab/T-DM1-dual-resistant cell line and analyzed the resistance mechanisms in this cell line. At first, the T-DM1 effectively inhibited the YES1-amplified trastuzumab-resistant cell line, but resistance to T-DM1 gradually developed. YES1 amplification was further enhanced after acquired resistance to T-DM1 became apparent, and the knockdown of the YES1 or the administration of the Src inhibitor dasatinib restored sensitivity to T-DM1. Our results indicate that YES1 is also strongly associated with T-DM1 resistance after the development of acquired resistance to trastuzumab, and the continuous inhibition of YES1 is important for overcoming resistance to T-DM1. 相似文献
975.
Hal Shaub Ken Leggett John Pandosh Keith Perrin Anne Searle Stan Sprague 《Lubrication Science》1999,5(4):391-416
The wear protection performance of unique boundary chemistry (UBC), both while in the engine and after removal, was tested with reference to commercial API SG, API SH/ILSAC GF-1, and API SJ/ILSAC GF-2 quality oils in two 80,450 km field tests, in modified and standard sequence tests, and in radiotracer engine studies. The radiotracer tests of UBC added to an API SJ/ILSAC GF-2 quality oil replicated previously published results of wear reductions achieved in a comparison of an API SH/ILSAC GF-1 oil with and without UBC. In extended Sequence IIIE runs, two engines, each lubricated with the same API SH/ILSAC GF-1 oil, were unable to complete the tests as a result of excessive oil consumption due to hot stuck rings. In contrast, two Sequence IIIE engines lubricated with the same API SH/ILSAC GF-1 oil treated with UBC completed the extended test without incident, even though the UBC-treated API SH/ILSAC GF-1 oil replaced the API SH/ILSAC GF-1 oil for the first oil drain interval only. A fully formulated SAE 5W–30 oil, which contained a full complement of UBC (20%), met all the requirements of API SH/ILSAC GF-1 quality and gave very low average and maximum cam and cam plus lifter wear on standard ASTM Sequence VE and IIIE tests. The same API SH/ILSAC GF-1 oil without UBC gave somewhat higher wear on both tests, but both oils met API SH/ILSAC GF-1 requirements. Wear metals analysis of a field test of 36 taxicabs, which compared an API SJ/ILSAC GF-2 quality oil to the same oil treated with UBC for the first drain interval, and also to a UBC-treated oil at every oil change, showed a reduction in the rate of used oil Fe accumulation for both methods of UBC treatment. This test also revealed a striking impact on Fe levels from Si found in used oil samples during an episode of Si contamination in local gasoline supplies. Finally, in a field test of 10 taxicabs, with parts measured before and after testing, wear reductions were observed in rings and bearings in UBC-treated cabs compared to those with API SG oil alone. 相似文献
976.
黄河花园口河段氨氮污染变化趋势及规律研究 总被引:1,自引:0,他引:1
黄河花园口河段位于黄河中游末端,是重要的饮用水源地。随着近几年排污量的增加,河水污染物超标情况日益严重,氨氮污染尤为突出。为了能使自来水厂更好地掌握黄河水氨氮的变化情况,从而能采用相应的处理措施,对1997~2004年黄河花园口的水质监测数据进行了详细的分析。结果表明,近8年来黄河花园口河段的氨氮污染变化趋势有如下规律:花园口河段氨氮污染近几年呈逐年下降的趋势,但污染还是较为严重;一年中6~10月氨氮含量较低,其他月份氨氮含量增高,且随温度的降低而增高。 相似文献
977.
Ken Sagawa 《Color research and application》1999,24(5):313-321
Visual comfort, which is defined here as the subjective impression of comfort caused by visual stimuli, to a colored image presented on a CRT display was investigated in terms of the distribution of CIE 1976 u,v saturation, suv, over the image. Variable saturation experiments, where the observer was asked to adjust saturation of the whole image to the most comfortable point, showed that saturation is a critical factor in the observer's estimation of comfort. Colorimetric analysis of the saturation distribution of the image showed that the mean value of suv over the image has a negative correlation to visual comfort, meaning that the lower the mean saturation, the more comfort is felt when viewing the image. The ratio of the higher to lower saturation components of the image, which means how much saturated color is relatively contained in the image, was also shown to be a critical factor affecting visual comfort. © 1999 John Wiley & Sons, Inc. Col Res Appl, 24, 313–321, 1999 相似文献
978.
Osamu Takahashi Kesao Sato Ken Goto Takashi Shirasaki Jun Sanekata Masahiko Amano Masaichi Endo 《Electrical Engineering in Japan》1999,127(2):32-41
An adjustable‐speed flywheel generator (FWG) can control both active power and reactive power rapidly. We have studied the effect of FWG installation on a large‐ capacity, long‐distance transmission system, especially when the system includes loops. In this paper, we describe the selection of FWG location, the selection of stabilizing control input signal, and the required quantities of FWG. FWG location is selected by a PQ‐sensitivity method, calculation of which is simple and permits easy understanding of the effect of both FWG's active and reactive power. As a stabilizing control input signal, we use bus voltage frequency instead of power flow because the flow changes stepwise by opening three‐phase single‐circuit. Additionally, we clarify the FWG quantities that must be designed, such as FWG's active power and reactive power. We considered FWG's slip to determine the quantity because the capacity of the exciter depends on slip. © 1999 Scripta Technica, Electr Eng Jpn, 127(2): 32–41, 1999 相似文献
979.
Cusum charts have good performance on not only the detection of the process change, but also the estimation of the change point. In this paper we will discuss the performance of cusum charts from the viewpoint of change-point estimation in the presence of autocorrelation. Supposing a first-order autoregressive (AR(1)) model as a primitive autocorrelated model, we examine the performance of the change-point estimator in cusum charts. Then we apply a two dimensional Markov process to the representation of the cusum statistic. In addition, we examine the relationship between the performance of the change-point estimator in the AR(1) model and in other primitive autocorrelated models by using the autocorrelation function. 相似文献
980.
Dérick Rousseau Alejandro G. Marangoni Ken R. Jeffrey 《Journal of the American Oil Chemists' Society》1998,75(12):1833-1839
Palm oil-soybean oil (POSBO) blends and lard-canola oil (LCO) blends were chemically interesterified with sodium methoxide.
Changes in crystal morphology using polarized light microscopy and crystal polymorphic behavior using X-ray diffraction spectroscopy
(XRD) were studied. Spherulitic crystalline particles, measuring 10–20 μm, were detected in palm oil (PO). These spherulitic
particles were characterized by a dense core surrounded by a lower-density halo region. PO fat-crystal morphology was not
greatly altered on addition of soybean oil (SBO), except for a gradual reduction in spherulite size as the amount of SBO in
the blends was increased. Chemical interesterification (IE) did not alter PO or POSBO blend fat-crystal morphology significantly.
Irregular particles and spherulites of different sizes and shapes were observed in lard, from small crystals to irregular,
angular crystal aggregates. Changes in lard fat-crystal morphology due to the addition of canola oil (CO) were concentration-dependent.
In general, spherulite diameter decreased with increasing CO addition. IE dramatically altered lard fat-crystal morphology—IE
induced the formation of more symmetrical spherulitic crystalline particles, and the halo-to-core ratio was increased significantly.
XRD spectroscopic analysis of POSBO blends revealed small changes in the long spacings of PO fat crystals with either blending
or IE; all values were close to 45 ?. Short spacings of fat crystals in noninteresterified (NIE) POSBO blends suggested the
predominance of β′ polymorphs. IE led to an increase in the proportion of the β polymorph in PO and POSBO blends. Long spacings
of NIE lard fat crystals suggested the presence of a bilayer structure in their unit cells (45 ?). Dilution with ≥10% canola
oil led to the appearance of a second reflection at 35 ?. β′ polymorphs were predominantly detected in NIE lard and NIE LCO
blends. The β polymorph became more evident with increasing addition of CO. Fat crystals in IE lard and IE LCO blends displayed
a single long-spacing reflection at 40 ?. IE of lard and LCO blends induced the formation of β polymorphs. 相似文献