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1.
裂缝性油气藏采收率:100个裂缝性油气田实例的经验总结 总被引:5,自引:2,他引:3
通过对世界上100个裂缝性油气藏的综合评价,研究储集层及流体本身的性质(包括孔隙度、渗透率、黏度、可动油比例、含水饱和度、润湿性及裂缝分布特征等)和驱动机制及油藏管理战略(优化日产量和采用不同类型的提高采收率技术)对其最终采收率的影响。将裂缝性油气藏分为4类:I类的基质几乎没有孔隙度和渗透率,裂缝是储存空间和流体流动的通道;Ⅱ类的基质有较低的孔隙度和渗透率,基质提供储存空间,裂缝提供流动通道;Ⅲ类(微孔隙)的基质具有高孔隙度和低渗透率,基质提供储存空间,裂缝提供流动通道;Ⅳ类(大孔隙)的基质具有高的孔隙度和渗透率,基质提供储存空间和流动通道,裂缝仅增加渗透率。对26个Ⅱ类油气藏和20个Ⅲ类油气藏的开采历史的研究表明:Ⅱ类油气藏的采收率受水驱强度和最优日产量控制,日产量过高会很容易破坏Ⅱ类油气藏,一些Ⅱ类油气藏如果管理得当,采收率可以很高,不需要二次或三次采油;Ⅲ类油气藏的采收率主要受岩石和流体本身性质的影响,特别是基质渗透率、流体重度、润湿性以及裂缝强度等,不进行二次或三次采油不可能完全开采,往往需要采用一些提高采收率的专门技术。以往将Ⅱ类和Ⅲ类裂缝性油气藏归为一类,认识它们的区别将有助于选择更好的开发策略。 相似文献
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Kraft lignin (KL), a phenolic polymer formed during the kraft pulping process, is presently burned as a low value fuel. For decades, researchers have attempted to use KL as an inexpensive substitute for phenol in phenol-formaldehyde (PF) resins, but no one has produced a commercially satisfactory KL-PF resin. This paper reviews the literature on the present status of KL-PF adhesives and makes recommendations on needed research.
Kraft lignin solutions are complex mixtures which have broad molecular weight distributions, high viscosities, relatively low reactivities, and low solubilities. Attempts to overcome these inherent problems include methylolation of lignin to improve reactivity, the use of co-solvents to improve solubility, and ultrafiltration to yield more homogeneous molecular weight fractions. Future research efforts need to focus on understanding the fundamental chemical and physical properties of kraft lignin and its resins. The search for an economic lignin-based wood adhesive should continue. 相似文献
Kraft lignin solutions are complex mixtures which have broad molecular weight distributions, high viscosities, relatively low reactivities, and low solubilities. Attempts to overcome these inherent problems include methylolation of lignin to improve reactivity, the use of co-solvents to improve solubility, and ultrafiltration to yield more homogeneous molecular weight fractions. Future research efforts need to focus on understanding the fundamental chemical and physical properties of kraft lignin and its resins. The search for an economic lignin-based wood adhesive should continue. 相似文献
3.
The gates of GaAs MESFETS rely on the formation of a Schottky diode between the semiconductor surface and a deposited metal and so are extremely sensitive to the nature of this interface. For this reason an investigation of surface damage and contamination by the various processing stages involved in IC fabrication has been undertaken. This paper outlines the results obtained from processes involved in activation of ion implantation through annealing with a dielectric encapsulant, wet chemical etching, and metallization. Methods for removing or minimizing the effects of processing damage or contamination are also investigated. 相似文献
4.
Measurement of Energy Expenditure in Elite Athletes Using MEMS-Based Triaxial Accelerometers 总被引:1,自引:0,他引:1
Andrew J. Wixted David V. Thiel Allan G. Hahn Christopher J. Gore David B. Pyne Daniel A. James 《IEEE sensors journal》2007,7(4):481-488
Fitness development and performance assessment of elite athletes requires an understanding of many physiological factors, many of these are direct and indirect measures of athlete energy expenditure. Many methods are physiological factor assessments and require the athlete to be constrained by laboratory equipment or periodic interruption of activity to take measurements such as blood samples are required to be taken. This paper presents a method that is entirely ambulatory and noninvasive, using microelectromechanical systems (MEMS) accelerometers. The commonly used output of commercial accelerometer-based devices (known as "counts") cannot discriminate activity intensity for the activities of interest. This, in conjunction with variability in output from different systems and lack of commonality across manufacturers, limits the usefulness of commercial devices. This paper identifies anthropometric and kinematic sources of inter-athlete variability in accelerometer output, leading to an alternate energy expenditure estimator based mainly on step frequency modified by anthropometric measures. This energy expenditure estimator is more robust and not influenced by many sources of variability that affect the currently used estimator. In this system, low-power signal processing was implemented to extract both the energy estimator and other information of physiological and statistical interest 相似文献
5.
Mazzocco Michèle M. M.; Freund Lisa S.; Baumgardner Thomas L.; Forman Lisa; Reiss Allan L. 《Canadian Metallurgical Quarterly》1995,9(4):470
An extensive evaluation was conducted with 16-yr-old monozygotic twins concordant for the fragile X full mutation but discordant for mental retardation. The clearly affected twin had an IQ score of 47; 77% of her neuropsychological z scores were at least 2 SDs below average. Her sister had an IQ score of 105 and average neuropsychological performance. However, each girl demonstrated relative verbal strengths and visual-spatial weaknesses. Their parents rated each girl as having significant problems with attention, conduct, anxiety-withdrawal, and hyperactivity. The girls did not rate themselves as having significant anxiety. These findings are consistent with group data on females with fragile X and demonstrate the wide range of effects associated with the fragile X full mutation. This case report implicates the importance of a psychosocial phenotype of fragile X independent of cognitive ability level. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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JC Allan M Velasquez-Tohom C Fletes R Torres-Alvarez G Lopez-Virula P Yurrita H Soto de Alfaro A Rivera J Garcia-Noval 《Canadian Metallurgical Quarterly》1997,91(5):595-598
Mass treatment of the human population with niclosamide was carried out in 2 villages in rural Guatemala where Taenia solium was endemic, to determine how this would affect the epidemiology of the parasite. Intestinal taeniasis was diagnosed by microscopy and coproantigen testing, and porcine cysticercosis by a specific Western blot. Before mass treatment, the prevalence of human taeniasis was 3.5%; 10 months after treatment it was 1%, a significant decrease (P < 10(-4)). All tapeworms that could be identified to the species level were T. solium. Similarly, the seroprevalence of antibodies to cysticercosis in pigs declined from 55% before treatment to 7% 10 months after treatment, once again a significant decrease (P < 10(-6)). These effects were seen in both villages. The possible use of mass chemotherapy as a tool in the control of T. solium is discussed. 相似文献
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Faking behavior was studied by comparing the personality profiles of 161 job applicants (motivated to be hired) with those of a control group of 73 graduate and undergraduate business students (motivated to obtain personal information for their own enlightenment). 44% of the Ss were female. Both groups were instructed to describe themselves honestly while completing the Self-Perception Test. Applicants did "fake good," scoring significantly higher on 10 of 11 scales; variance was significantly lower among applicants on 7 scales. Gender differences, consistent with cultural stereotypes, occurred on 5 scales. Overall profile shapes were virtually identical for student and applicant groups, suggesting that faking may not have dramatically altered the essence of the personality constructs. The scales of the test were found to have high reliability. Scale independence is discussed in relation to the 5-factor model of personality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献