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231.
预测井眼稳定性的力学化学耦合方法 总被引:13,自引:8,他引:5
在井眼力学稳定性评价的基础上,将硬脆性页岩水化后岩石强度等参数的变化规律用于页岩水化前后坍塌压力变化的对比分析,结果表明,地层坍塌压力当量密度随页岩水化程度的增加逐渐升高。给出了预测井眼稳定性的力学化学耦合方法,并将该方法应用于现场生产中,取得了较好的预测效果 相似文献
232.
介绍了在直流电弧放电法制备富勒烯过程中,从阴电极表面收集到大量的碳纳米管及巴基葱,产生率达到50%,并用电子显微镜对其进行了观察和初步研究。 相似文献
233.
M Yaono R Hasegawa K Kato J Kimura C Lin M Tada T Shirai 《Canadian Metallurgical Quarterly》1996,98(2):145-149
We attempted to purify endogenous growth factors of chick embryonal retinal pigment epithelial cells from bovine neural retina. Ammonium sulfate precipitation, gel filtration, and anion exchange column chromatography were used. Though only partially purification, bovine retinal extract had two effects, growth and transformation, on chick embryonal pigment epithelial cells. We think that these purified factors may be novel from the estimation of their molecular weight by gel filtration. 相似文献
234.
235.
A technique for SiO2 formation by liquid-phase deposition (LPD) at nearly room temperature for low-temperature processed (LTP) polysilicon thin-film transistor (poly-Si TFT) was developed. LPD SiO2 film with a lower P-etch rate shows a dense structure. LPD SiO2 also exhibits good electrical characteristics. LTP poly-Si thin-film transistors (TFTs) with LPD SiO 2 as the gate insulator have been fabricated and investigated. Their characteristics indicate performance adequate for their use as pixel transistors in liquid crystal displays (LCDs) 相似文献
236.
Converting cysteine 543 to tyrosine in the influenza virus hemagglutinin (HA) introduces both a basolateral sorting signal and an internalization signal into the HA cytoplasmic domain. Another HA mutant, HA+8, contains eight additional amino acids at the end of the cytoplasmic domain that include a powerful internalization signal. HA+8 was also sorted efficiently to the basolateral surface of Madin-Darby canine kidney cells. The simplest explanation for the observation that multiple sorting phenotypes depend upon the same small amino acid sequence is that certain tyrosine-based internalization signals might also function as basolateral sorting signals. To test this hypothesis, second-site mutations were introduced into HA C543Y or HA+8 to determine if the internalization and basolateral sorting functions can be separated. For HA C543Y, the same sequence positions were important for both basolateral sorting and internalization, but the two functions responded differently to individual amino acid replacements, indicating that they were distinct. For HA+8, the basolateral sorting signal required the same tyrosine as the internalization signal, but did not share any other characteristics. Thus, even when basolateral sorting signals that depend on tyrosine overlap or are co-linear with internalizations signals, the two sorting processes are sensitive to different characteristics of the sequence. 相似文献
237.
Although stereotyped behavior in adult rats is partly regulated by dopamine (DA) D2 autoreceptors, previous attempts to demonstrate D2 autoreceptor regulation of stereotypy in developing rats have been unsuccessful. In the present study, two highly selective D2 autoreceptor agonists were used to demonstrate D2 autoreceptor regulation of spontaneous stereotyped behavior in developing rats. Both SND 919 and PD 128483 produced significant dose-dependent decreases in the stereotypy counts of 21-day-old, 35-day-old, and adult rats. There was a 51% decrease in the stereotypy counts of 21-day-old rats injected with SND 919, 0.05 mg/kg, compared to a 36% decrease in the counts of rats pretreated with haloperidol. Similarly, PD 128483 significantly decreased the stereotypy counts of 21-, 35-day-old, and adult rats in a dose-dependent fashion. There was a 58% decrease in the stereotypy counts of 21-day-old rats injected with PD 128483, 0.1 mg/kg, compared to a 17% decrease in counts when the rats were first treated with haloperidol. The effect of haloperidol plus PD 128483 was significantly different from the effect of PD 128483 alone. Injection of SND 919 or PD 128483 had no significant effects on the stereotypy counts of 10-day-old rats. The results suggest that DA D2 autoreceptor-mediated regulation of spontaneous stereotyped behavior is functional at 21, but not 10, days of age. 相似文献
238.
239.
MH Boyle DR Offord D Campbell G Catlin P Goering E Lin YA Racine 《Canadian Metallurgical Quarterly》1996,41(9):549-558
OBJECTIVE: To describe the methodology of a province-wide, cross-sectional, epidemiologic study of psychiatric disorder among those aged 15 years and over living in household dwellings in Ontario. METHOD: Respondents for the survey were drawn from households (N = 13002) participating in a province-wide health survey. One person per household was selected, and 9953 (76.5%) participated. RESULTS: Participants and nonparticipants were similar to each other. An extensive array of data, including measures of psychiatric disorder classified using a revised version of the Composite International Diagnostic Interview (CIDI), are available for all respondents. CONCLUSIONS: The Ontario Health Supplement is contained in a public-use data file at the Ontario Ministry of Health and is available to investigators for study. A strong survey design, careful measurement, and acceptable levels of response provide the rationale for our inviting researchers to access and use the Ontario Health Supplement data base. 相似文献
240.
The sub-rating channel assignment strategy for PCS hand-offs 总被引:2,自引:0,他引:2
Yi-Bing Lin Noerpel A.R. Harasty D.J. 《Vehicular Technology, IEEE Transactions on》1996,45(1):122-130
A new personal communications services (PCS) hand-off scheme is proposed. This scheme provides for hand-off to radio ports on which there is no free channel by “sub-rating” an existing connection. With sub-rating, an occupied full-rate channel is temporarily divided into two half-rate channels: one to serve the existing call and the other to serve the hand-off request. The blocking probabilities (combined forced terminations of existing calls and blocking of new call attempts) of this new scheme compare favorably with the standard scheme (nonprioritizing) and the previously proposed prioritizing schemes. The costs for this scheme are presented and discussed, as well as the additional procedural complexity of implementing on-the-fly sub-rating and the impact of continuing the conversation on a lower rate channel (which may lower speech quality of increase battery drain). Analytical models and simulations investigating the traffic impacts are presented, as are the results that show that even in the highest offered load considered a 3-min conversation in the busy hour experiences less than half a second of sub-rated conversation on average and only about 3% of the calls experience more than 5.12 s of sub-rated conversation. This scheme can increase capacity by 8-35% for systems with 1% call incompletion probability 相似文献