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121.
任丘油田雾迷山油藏抽油机井系统效率初步探讨   总被引:3,自引:1,他引:2  
总公司1996年对任丘雾迷山油藏抽油机井进行测试,系统效率高达51%~68%,其结果出乎意料。从影响抽油机系统效率的几大因素入手,分析出任丘雾迷山油藏抽油机井系统效率高的主要原因。任丘雾迷山油藏属裂缝性破酸盐岩油藏(即灰岩油战),由于其裂缝发育、渗透性好、油层厚度大、地层温度高、油气比小、饱和压力低等,使得抽油机井生产呈现如下特点:()大泵径,长冲程,低冲次大排量采油;(2)中浅京挂,小沉没度;(3)抽汲流体为液体单相,泵充满程度高;(4)部分井为连抽"带喷"状态,抽油系活塞底部受力大;(5)井液粘度低,油井不结蜡,摩阻损失小。由于这些特点以及近年来使用的新型节能抽油机,使得抽油机井系统效率大大高于其它油田抽油机井系统效率。  相似文献   
122.
本文以NH3-H2O系统Gibbs自由能、熵、焓和汽液相平衡的热力学模型为基础,用松弛法进行了无水氨精馏塔的模拟计算。改变无水氨采出比、回流比(直汽量)和进料板位置均影响蒸馏效果。  相似文献   
123.
本文用计算机数字模拟方法研究了电活性分子多层Z型L-B膜修饰电极的循环伏安行为。计算了电极与修饰L-B膜分子第一层之间的电荷转移速度常数K_o,L-B膜分子层间的电荷转移速度常数k_i;对峰电位差△E_p及阳极峰面积Q的影响,以及在不同条件下各层分子的氧化态分数随扫描时间的变化。为研究和设计电活性分子修饰电极的实际体系提供了大量数据和信息。  相似文献   
124.
介绍了XMC-3000工业热水锅炉群集散控制系统的硬件组成及特点,描述了锅炉燃烧系统、定压系统的控制方案和系统供热调节模型,最后给出了系统的主要功能。  相似文献   
125.
Actinobacillus actinomycetemcomitans is frequently associated with severe periodontitis. Many periodontitis patients have elevated levels of serum IgG antibodies to A. actinomycetemcomitans, but the role of these antibodies is unknown. This study evaluated the functional capacity of anti-A. actinomycetemcomitans IgG antibody to enhance phagocytosis of A. actinomycetemcomitans by polymorphonuclear leukocytes. Chemoluminescence assays were done using sera from 64 subjects, 61 of whom had severe periodontitis; results were compared with the subject's anti-A. actinomycetemcomitans IgG titer and avidity. There was a strong correlation between chemoluminescence and antibody log titer (P < .00001) and a weak correlation between chemoluminescence and antibody avidity (P < .05). The results support the hypothesis that anti-A. actinomycetemcomitans IgG antibodies are important in promoting phagocytosis and killing of A. actinomycetemcomitans. Subjects who develop high levels of highly avid antibodies against A. actinomycetemcomitans may have greater resistance to continued or repeated infection by this pathogen.  相似文献   
126.
A genetic linkage map of human chromosome 21q (HC21q) containing 43 markers genotyped by the polymerase chain reaction in the CEPH pedigrees is presented. The markers placed on this map are highly polymorphic with an average heterozygosity of 61%. The average interval size of the markers localized at 1000:1 odds is 2.5 cM. The map has a total length of 65.5 cM, with male and female lengths of 47.7 and 83.3 cM, respectively. The genotypes used in the construction of this map were subjected to rigorous error checking, which is reflected in the shorter map length compared to previous maps; the estimated error rate in genotyping is less than 0.04%. As noted in previous linkage maps there is increased recombination in females on proximal HC 21q and in the male in a region near the telomere. This map of HC 21 represents a highly informative and dense meiotic linkage map and will be useful in linking disease phenotypes to loci on this chromosome.  相似文献   
127.
Growth hormone (GH) has recently been shown to affect polymorphonuclear neutrophil granulocyte (PMN) function and to be secreted by mononuclear cells, indicating that the hormone may be active in an immunophysiologic network, acting as an endo- or paracrine priming agent. The purpose of the present study was to evaluate the chemotactic responsiveness of canine peripheral PMN in a dog with acromegaly, caused by spontaneous, progesterone-induced hypersecretion of GH and, secondary to this, a seven-fold increase in insulin-like growth factor I (IGF-I). The chemotactic responsiveness towards zymosan-activated serum (ZAS) and leukotriene B4 (LTB4) was evaluated at a time when the dog suffered from acromegaly and again 57 days after corrective surgery (ovariohysterectomy). The experiments showed that PMN from the patient exhibited enhanced chemotactic migration that appeared to be associated with the hypersomatotropic condition as judged from the reversibility of the phenomenon. The glucose intolerance and elevated serum alkaline phosphatase that were observed in the acromegalic dog were also shown to be reversible following surgery.  相似文献   
128.
The effects of adenosine and sodium nitroprusside (SNP) on central hemodynamics and myocardial blood flow and metabolism were investigated postoperatively after elective coronary artery bypass (CABG) surgery in ten sedated and mechanically ventilated patients in the intensive care unit. During three consecutive 15-min periods, SNP (0.8 +/- 0.1 micrograms.kg-1 x min-1), adenosine (88.9 +/- 13.3 micrograms.kg-1 x min-1), and then again SNP (0.7 +/- 0.1 micrograms.kg-1 x min-1) were infused to control postoperative hypertension at a mean arterial pressure of approximately 80 mm Hg. Systemic and pulmonary hemodynamics and global (coronary sinus flow, CSF) as well as regional (great cardiac vein flow, GCVF) myocardial blood flow and metabolic variables were measured. During adenosine infusion, in comparison to SNP, heart rate was unchanged, stroke volume index and cardiac index increased (24% and 32%, respectively), and the systemic vascular resistance index decreased (-26%). Mean pulmonary arterial pressure (24%) as well as pulmonary capillary wedge pressure (27%) and central venous pressure (18%) were higher with adenosine compared to SNP. Adenosine also increased CSF and GCVF (108% and 103%, respectively) without altering the CSF/GCVF flow ratio compared to SNP. Furthermore, adenosine increased the coronary oxygen content (51%) and decreased the arterio-great cardiac vein oxygen content difference (-48%) without changing regional myocardial oxygen consumption, indicating a more pronounced hyperkinetic myocardial circulation compared to SNP. In addition, adenosine infusion decreased arterial PO2 (-11%) and increased the intrapulmonary shunt fraction (57%). The PR interval time of the electrocardiogram was prolonged (12%) and the ST segment was more depressed during adenosine infusion compared to SNP.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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