小井眼水平井钻具通过能力分析及应用

针对小井眼水平井环空间隙小、曲率大的特点,应用间隙元法对下部钻具组合进行了非线性静力学分析;根据钻具变形、应力、摩阻力、接触力和小井眼内弯外壳螺杆钻具的提放试验,建立了钻具通过能力判定条件和计算公式。对小井眼水平井可组配的2.75°和2.25°2种弯螺杆钻具,在套管和裸眼井段内的通过能力进行了分析与评价,并在大庆油田得到应用和验证。     

Contribution of nitric oxide to the acute antihypertensive effect of blockers of AT1 angiotensin receptors in spontaneously hypertensive rats

The acute vasodepressor effect of AT1 angiotensin receptor blockers losartan and CL329167 was compared in spontaneously hypertensive rats (SHR) pretreated and not pretreated with NG-monomethyl-L-arginine (LNMMA; 15 mg/kg i.v. bolus plus infusion at 10 mg/kg/h), an inhibitor of nitric oxide (NO) synthesis. The antihypertensive effect of losartan (30 mg/kg, i.v.) in SHR pretreated with LNMMA (-13 +/- 4 mmHg) was greatly diminished (P < 0.01) relative to the antihypertensive effect of losartan in SHR not pretreated with LNMMA (-44 +/- 8 mmHg). Similarly, the antihypertensive effect of CL329167 (5 mg/kg, i.v.) in SHR pretreated with LNMMA (-12 +/- 3 mmHg) was surpassed (P < 0.01) by the antihypertensive effect in SHR not pretreated with LNMMA. (-41 +/- 4 mmHg). However, pretreatment of SHR with LNMMA did not minimize the vasodepressor effect of prazosin, isoproterenol or sodium nitroprusside. The impairment in vasodepressor responsiveness to losartan in rats pretreated with LNMMA was not demonstrable in rats concurrently receiving sodium nitroprusside to correct for the loss of endogenous NO, or atrial natriuretic peptide which also increases vascular cGMP. These data suggest that a mechanism mediated by NO and/or cGMP is necessary for the full expression of the acute antihypertensive effect of AT1 angiotensin receptor blockers in SHR.     

FCC原料加氢预处理催化剂FF-14的实验室研究

为适宜进口高硫原油的加工，抚顺石油化工研究院研制开发了在保持较高脱氮活性的同时，具有高脱硫活性的新型Fcc原料加氢预处理催化剂。该催化剂以Mo-Ni-Co为活性组分，具有孔体积、比表面积较大，堆密度较高的特点。小型活性评价试验结果表明：在反应氢压10．0MPa、氢油体积比1000：1、体积空速1．0h^-1的工艺条件下，FF-14催化剂的脱硫和脱氮活性高于在国内广泛应用的蜡油加氢处理参比催化剂。在1800h连续运转过程中，FF-14催化剂脱硫率始终保持在98％左右，催化剂的活性稳定性较好。     

稠油精细注汽配套技术研究及应用

曙光油田稠油、超稠油油藏已经大规模开发,为了提高该类油藏的最终采收率,提出并实施了稠油精细注汽配套技术。该配套技术于2006年在曙光油田累计实施应用了111井次,措施成功率88.3%,平均单井增产原油317.1m~3,取得了较好的应用效果。     

用稳流试验台和等折射率技术进行内燃机气缸和燃烧室中紊流运动的研究

本文报导了利用等折射率技术和激光多普勒测速技术在稳态流动模拟试验装置上对直喷式柴油机气缸和燃烧室内的紊流运动所进行的研究。由于在这种情况下激光束在透明材料制成的燃烧室内表面上不再受到折射或反射，所以可以在复杂形状燃烧室内的任一部位进行测量，并可保持高的有效数据率（Ｄａｔａｒａｔｅ）。由于有足够高的数据率，所以有关紊流的一些详细信息，如紊流强度、尺度、高次矩、能谱密度等都可以得到，而这些参数对燃烧都有重要影响。在本研究中对圆柱形燃烧室和方形燃烧室内的流场进行了测量，并获得了令人满意的结果。     

Error-rate analysis for multirate DS-CDMA transmission schemes

We analyze and compare the error performance of a dual-rate direct-sequence code-division multiple-access (DS-CDMA) system using multicode (MCD) and variable-spreading gain (VSG) transmission in the uplink. Specifically, we present two sets of results. First, we consider an ideal additive white Gaussian noise channel. We show that the bit-error rate (BER) of VSG users is slightly lower than that of MCD users if the number of low-rate interferers is smaller than a specific threshold. Otherwise, they exhibit similar error performance. Second, we look at multipath fading channels. We show that with diversity RAKE reception, the VSG user suffers from a larger interference power than the MCD user if the channel delay spread is small. The reverse is true for a large delay spread. However, a larger interference power in this case does not necessarily lead to higher error probability. Essentially, our results for both cases show that: 1) in addition to the signal-to-interference ratio (SIR), the difference in error performance between the two systems strongly depends on the distributions of multiple-access and multipath interference; 2) for practical cellular communications, performances for both systems are expected to be similar most of the time.     

三峡茅坪溪防护坝沥青混凝土心墙变形监测

在对茅坪溪防护坝施工期沥青混凝土心墙进行安全监测时,对心墙应变、应力、变形及温度状态等观测资料进行了较详细的分析探讨.目前监测结果为:心墙底部压应力测值增长与心墙高程升高关系协调.心墙不同高程处的应变主要受温度、上部荷载及两侧过渡料性质影响,从测值分析,心墙中上部应变随高程升高其值增长较快.心墙与过渡料间位错变形为-0.32～-32.95 mm,反映心墙压缩变形大于两侧过渡料沉降变形,且心墙中部变形较上下部变形要大.底部心墙与基座间水平变形为-1.85～17.89 mm,变形初期主要受施工影响,后期施工对其影响较小,总体变形稳定.分析表明心墙现阶段变形稳定,符合土石坝变形基本规律.     

Generalized nonlinear FET/HEMT modeling

A modeling procedure which provides an accurate large-signal response for variation in bias, input power level, and fundamental frequency for FET/HEMT transistors is designed. A procedure for measuring the large-signal input response on an easily implemented system is presented. The technique is illustrated by designing a nonlinear PHEMT model, which includes an accurate large-signal input response and works with variations in the aforementioned input conditions. © 2004 Wiley Periodicals, Inc. Int J RF and Microwave CAE 14, 122–133, 2004.     

Selective Oxidation of Isobutane to Methacrolein over Mo–V–Te–Sb Mixed Oxide Catalysts with Different Antimony Contents

A series of MoV_0.3Te_0.23Sb_x (x=0–0.6) mixed oxides were prepared and investigated for the selective oxidation of isobutane. Among them, MoV_0.3Te_0.23Sb_0.5 showed the best methacrolein selectivity (as high as 39%), and the yield to methacrolein reached 7.8% at 20.0% isobutane conversion at 470 °C.