不同降压体系降压效果实验研究

北一区三类油层储层物性变化大、剩余油分布零散,导致其水驱挖潜难度大,在水驱开发过程中往往出现注水井注入压力高,吸水能力差的问题,针对上述问题进行实验室降压增注实验研究,对比不同配方降压剂对水驱提高采收率的影响,并根据北一区三类油层注入水有严重的结垢趋势,提出在降压剂配方中加入阻垢剂的措施。纳米聚硅和生物酶体系的降压率分别为18.79%,16.86%,4种活性剂体系的降压率分别是22.09%,25.47%、20.20%,21.55%,活性体系的降压率会随着注入量的增加出现小幅度的上升。综合分析实验结果提出两种可供现场使用的方案:注入甜菜碱一元活性体系,注入浓度为0.2%,注入量为0.1 PV;由0.2%石油磺酸盐和0.6%阻垢剂组成二元体系,优选0.15 PV的注入量。

规范应用降压药,积极防控高血压

高血压是最为重要的心血管病危险因素之一。近30年来,国内外先后完成了数十项大型随机临床试验,证实积极合理的降压治疗有助于大幅降低心血管事件风险。正因如此,降压达标已成为防治心血管疾病的核心策略。目前,我国高血压的防治现状仍不尽如人意,高血压患者的诊断率、治疗率、达标率仍处于较低水平。虽然改善生活方式是预防和治疗高血压的重要举措,但多数患者仍需要降压药物治疗才能使血压得到有效控制,因此合理应用降压药物是提高降压达标率的关键。在临床工作中，需要注意以下几方面问题。

上海地区门诊高血压人群降压治疗现状

目的了解高血压病患者血压水平、合并症、降压达标率以及用药的状況。方法通过在上海27家二、三级医院心血管病专科门诊就诊人群采用测量血压和问卷调查相结合的方法进行调查。结果2 681例高血压病患者平均年龄为(65±12)岁,平均病程为(12±10)年,平均血压为(156．3±13．9)／(82．5±9．8)mm Hg(1 mm Hg=0．133 kPa);合并心明梗死、心力衰竭、脑卒中、肾功能衰竭、尿蛋白阳性、糖尿病的高血压患者分别为4．77％、9．18％、16．93％、2．98％、10．37％和20．14％;年龄在<44岁、44-54岁、55-64岁、65-74岁和>75岁各组患者血压控制在140／90 mm Hg以下的分别为29．6％、35．1％、41．7％、44．1％和51．1％,总降压达标率为43．2％。降压达标与未达标的两组中,年龄、病史中最高收缩(SBP)压、病史中最高舒张压(DBP)、病程和体重指数的差异均有统计学意义(P值均<0．000 1)。降压未达标的患者中,单纯SBP升高者占39．6％,单纯DBP升高者占14．9％,SBP和DBP均升高者占45．5％。3组年龄、病史中最高SBP、病史中最高DBP、病程、BMI、心血管危险因素分层和有无并发症等指标的差异均有统计学意义(P值均<0．0001):服用1种降压药物使血压达标的仅占20．6％,而在未达标的高血压患者中,0．9％的患者未服药,44．6％者仅服用了1种降压药。使用单种抗高血压药物治疗的占46．1％,药物依次为钙拮抗剂(CCB)36．0%、血管紧张素转换酶抑制剂(ACEI)29．4％、复方制剂19．0％、血管紧张素Ⅱ受体拮抗剂(ARB)6．8％、β-受体阻滞剂4．3％、利尿剂4．1％、α-受体阻滞剂0．2％,在联合用药时用得最多的是CCB、ACEI、利尿剂。结论上海地区心血管专科门诊的降压达标率为43．2％,年龄大、基础血压高、病程长和BMI等因素均可影响降压达标,单纯SBP升高患者的血压较难控制,有较大一部分高血压患者降压治疗不足,如能强化治疗、合理用药,完全能够提高降压达标率。CCB和ACEI是使用最为广泛的抗高血压药物,复方降压制剂有较好的应用前景。

基层对高血压病降压联合调脂治疗的疗效观察

目的探讨农村基层医院对高血压病采用降压和他汀类药物联合治疗的降压疗效和临床意义。方法选取近4年来随访治疗的高血压病病人169例,按单纯服用降压药物血管紧张素转换酶抑制剂(ACEI)或ACEI加钙拮抗剂(对照组105例)和联合服用他汀类调脂药物(观察组64例),随机进行分组,干预治疗历时3个月以上。然后对比分析血压控制的达标率。结果观察组的血压达标率为89.1%,明显高于对照组的71.4%(P<0.05)。结论对高血压病病人采用降压联合低剂量他汀类调脂药物治疗的降压疗效明显优于单纯给予抗高血压药物的降压疗效。

表面活性剂改善稠油油藏水驱开发效果实验研究——以东辛油田深层稠油油藏为例

针对深层稠油油藏原油粘度高、渗流阻力大、常规水驱效果差、水井注入压力高及注入能力低等现状,以东辛油田深层稠油油藏为例,在评价表面活性剂适应性的基础上,通过低界面张力活性体系室内岩心驱替实验,研究了界面张力、渗透率、注入量和注入速度4因素对表面活性剂改善水驱效果的影响。结果表明:使用的表面活性剂与研究区块的注入流体具有很好的配伍性,表现出较好的降低油水界面张力的能力,质量分数为0.01%的表面活性剂溶液与模拟油的界面张力在70℃时最低可达10-2mN/m数量级;一次水驱结束后注入表面活性剂溶液段塞,可降低注入压力,改善水驱开发效果,并且当油水界面张力越低、注入量越大、注入速度越低时,二次水驱降压效果越好,采收率提高幅度越大,降压率最高为18.0%,采收率最大可提高15.7%;在相同实验条件下,当气测渗透率由256.65×10-3μm2降至36.16×10-3μm2,注入0.7倍孔隙体积表面活性剂溶液后,二次水驱降压率由17.1%降至10.0%,采收率提高幅度由15.7%降至11.7%,说明当渗透率较低时,因渗流条件变差,导致表面活性剂改善水驱效果变差。

致密储层纳米增注技术研究与应用

针对魏家楼致密储层油藏注水压力上升快的问题,引入了纳米增注技术,通过微细管和岩心驱替实验装置对纳米增注技术的增注原理和影响因素进行了分析。结果表明:纳米增注剂能够改变岩石润湿性,可使亲水储层改变为中性或亲油储层,减少亲水储层孔喉表面形成的水膜的厚度;纳米增注剂还可吸附在孔喉表层,使孔喉表层的水化膜剥离,增大孔喉有效半径,降低流体阻力,从而增加地层吸水能力。微细管驱替实验表明,质量分数为0.010%的纳米增注液,对直径为50~100μm的微细管降压效果较好,降压率最大可达30.1%;天然岩心驱替实验表明,纳米增注液注入量为1倍孔隙体积、吸附时间大于36 h时,降压效果较好,降压率达40.0%。魏家楼油田降压增注现场试验结果表明,纳米增注剂能使注水井注入压力降低2.4 MPa。该研究结果对致密储层油藏高压欠注井治理具有很好的应用价值。

ARB固定复方制剂临床用药需关注的几个问题

近年来,随着一系列流行病学研究与大规模临床试验的陆续揭晓,人们对高血压危害性的认识日臻加深,积极降压与降压达标已被认为是现代降压策略的核心.……

注入时机对低矿化度表面活性剂驱油的影响

近年来,针对低矿化度水为注入液的研究结果表明,低矿化度水在一定程度上有提高采收率的作用。相比于低矿化度水驱,低矿化度表面活性剂驱在提高采收率方面具有更大的优势。然而,低矿化度表面活性剂注入时机对驱油的影响缺乏相关研究。选择一种能在低盐度环境下获得油水超低界面张力的阴离子表面活性剂KPS,在不同转注时机下进行低矿化度表面活性剂驱油实验。结果表明,注入时机对采收率、含水率、注入压力及降压率都有较大影响。注入时机越早,最终采收率越高,当高矿化度水驱至含水率分别为60.5%、81.5%、98.1%后转注低矿化度表面活性剂,采收率增值为38.9%、25.3%、15.7%,最终采收率为74.3%、67.8%、65.1%;注入时机越早降压率越低,降压率最大差值为33.1%。

Sintering preparation of porous sound-absorbing materials from steel slag

Porous sound-absorbing materials were prepared from steel slag using waste expanded polystyrene（EPS） particles as pore former.The influences of the experimental conditions such as fly ash content,sintering temperature,sintering time,and pore former addition on the performance of the porous sound-absorbing materials were investigated.The results show that the porosity of the specimens can reach above 50.0%;the compressive strength and average sound-adsorption coefficient of the sintered specimens are above 3.0 MPa and 0.47,respectively.The optimum preparation conditions for the steel slag porous sound-absorbing materials are as follows：mass fraction of fly ash 50%,waste EPS particles 3.6 g,sintering temperature 1100℃,and sintering time 7.5h,which are determined by considering the properties of the sound-absorbing materials,energy consumption and cost.

Effect of WS_2 addition on electrical sliding wear behaviors of Cu-graphite-WS_2 composites

Four kinds of Cu-based composites with different mass ratios of graphite and WS2 as lubricants were fabricated by hot-pressing method. Electrical sliding wear behaviors of the composites were investigated using a block-on-ring tribometer rubbing against Cu-5%Ag alloy ring. The results demonstrated that 800 ~C was the optimum sintering temperature for Cu-graphite-WS2 dual-lubricant composites to obtain the best comprehensive properties of mechanical strength and lubrication performance. Contact voltage drops of the Cu-based composites increased with increasing the mass ratio of WS2 to graphite. The Cu-based composite with 20% graphite and 10% WS2 showed the best wear resistance due to the excellent synergetic lubricating effect of graphite and WS2. The reasonable addition of WS2 into the Cu-graphite composite can remarkably improve the wear resistance without much rise of electrical energy loss which provides a novel principle of designing suitable sliding electrical contact materials for industrial applications.

固定复方制剂应作为基层医疗机构高血压治疗的首选

高血压是最常见的心血管病之一,同时也是冠心病、心力衰竭、脑卒中等多种疾病的重要病因和危险因素。中国高血压防治指南指出90%的高血压患者就诊于城镇社区和乡村卫生服务机构,基层医疗机构是防治高血压的主战场,基层医生是高血压防治的主力军。因此,基层高血压的检出、诊断评估、治疗和管理工作至关重要。

电荷泵电路的电压调节结构及工作原理

稳压输出的电荷泵电路是一种新型ＤＣ／ＤＣ变换器。介绍了其电压调节结构及工作原理。

Analysis and Design of a High-Stability,High-Accuracy,Low-Dropout Voltage Regulator

A high-accuracy,low-dropout （LDO） voltage regulator is presented. Using the slow-rolloff frequency compensation scheme, the LDO effectively overcomes the stability problem, facilitates the use of a ceramic capacitor, and improves the output voltage accuracy, which is critical for powering high-performance analog circuitry. The slow-rolloff compensation scheme is realized by introducing three pole-zero pairs, including the proposed polezero pair and sense zero. The post-layout simulation results demonstrate that this LDO has robust system stability, a high open-loop gain, and a high unit-gain frequency,which lead to excellent regulation and transient response performance. The line and load regulation are 27μV/V and 3.78μV/mA, and the overshoots of the output voltage are less than 30mV,while the dropout voltage is 120mV for a 150mA load current.

Numerical Simulation and Experimental Study on the Performance of Gas/liquid Spiral Separator

The gas/liquid spiral separator, a key component in the compressed air system, was used to remove liquid and oil from gas stream by centrifugal and gravitational forces. To optimize the design of the separator,the relationship between the performance and structural parameters of separators is studied. Computational fluid dynamics (CFD) method is employed to simulate the flow fields and calculate the pressure drop and separation efficiency of air-liquid spiral separators with different structural parameters. The RSM (Reynolds stress model)turbulence model is used to analyze the highly swirling flow fields while the stochastic trajectory model is used to simulate the traces of liquid droplets in the flow field. A simplified calculation formula of pressure drop in spiral structures is obtained by modifying Darcy's equation and verified by experiment.

军队中青年高血压患者知识认知调查及血压影响因素分析

目前,高血压病已成为军队中青年官兵的常见疾病,患病率逐年增高,且日趋年轻化。长期高血压可导致脑卒中、心血管疾病等严重并发症,具有高度的致死率和致残率,严重影响军队指战员的健康,削弱军队战斗力。由于高血压是一种慢性疾病,一旦发生,就需要终身管理。加强对高血压患者的健康教育,指导患者掌握高血压的防治知识和技能,促其养成良好的遵医行为,是提高降压达标率、减少并发症的最有效途径。

硝苯地平联合依那普利治疗高血压76例观察

目的探讨广大基层社区人群硝苯地平缓释片联合依那普利治疗高血压的降压疗效。方法选择在社区卫生服务中心就诊的门诊及住院高血压患者76例,采用开放自身前后对照试验,联合应用硝苯地平缓释片与依那普利随访治疗8周,观察血压和不良反应。结果治疗4周时收缩压达标率男性为71.43%,女性为67.65%,舒张压男性为73.81%,女性为70.59%;8周时收缩压达标率男性为76.19%,女性为70.59%,舒张压男性为78.57%,女性为76.47%.治疗4周末、8周末男女性血压达标率比较差异均有统计学意义(P<0.01)。结论硝苯地平缓释片联合依那普利降压达标率较高,不良反应发生率低,价格便宜,适合中小城市广大基层社区人群中高血压患者选择。

Measurement-based approach for identification of static load model of electric power system

The validity of electric power system simulation or prediction models depends on static load model. Measurement- based approach is the unique method to identify them adequately. The measured power depends on both load reaction to supply voltage alteration and random process of load alteration Basically, there is no any universal method that can single out the inherent static load model from experimental data. The paper offers a proprietary technique which is the particular solution of the task. The technique considers the selection of neighboring measurement pairs with the supply voltage altering significantly be-tween them, the exclusion of selected pairs by load power factor and subsequent selection of the inherent static load model presented as the polynomial load model. The usage of the technique to identify static load model at “Fenster” industrial enterprise （in Borisov city） is presented. The ideas considered in the paper can be used for future development of static load model identification methods with the data obtained during both active experiment and in other operating models of electric power systems.

Identification of voltage sag source location using S and TT transformed disturbance power

An alternative method was introduced for voltage sag source location based on S and TT transformed disturbance powers. It is done to avoid the wrong and inconclusive detection of conventional disturbance power method proposed in the literature. Unlike in the case of the traditional method, the proposed method first transforms the recorded voltage and current during the sag event to some special features before calculating the new version of disturbance powers. The effectiveness of the proposed method has been verified through simulation and actual data from an industrial power system. The results show that the presented method can correctly detect the location of voltage sag source.

A Model for Predicting Holdup and Pressure Drop in Gas- Liquid Stratified Flow

The time-dependent liquid film thickness and pressure drop were measured by using parallel-wire conductance probes and capacitance differential-pressure transducers. Applying the eddy viscosity theory and an appropriate correlation of interfacial sear stress,a new two-dimensional separated model of holdup and pressure drop of turbulent/turbulent gas-liquid stratified flow was presented. Prediction results agreed well with experimental data.

Experimental investigation of oil particles filtration on carbon nanotubes composite filter

Due to the lipophilicity of carbon nanotubes (CNTs),the carbon nanotubes composite filter for removing oil particles in cooking fumes is synthesized. The composite filter was fabricated by the chemical vapor deposition (CVD) method. The filtration characteristics of the resultant filter and the influence of the parameters were investigated. The results show that the filtration efficiency of the CNT filter during the saturation period is 99.92%, which satisfies the high efficiency particulate air (HEPA) standard. Pressure drop increases linearly before saturation and the pressure drop at the saturation stage is only two times that of the initial stage, which is far less than that of conventional glass fiber filters. The efficiency increases by enhancing filtration velocity. Pressure drops in the composite filter at the equilibrium stage are equal under different aerosol concentrations. The increase in concentration can improve the efficiency of composite filters. Therefore, the CNT filter is suitable for decreasing oil particle pollution due to its lower increase ratio of pressure drop and higher efficiency.