mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Numerical simulation of flocculation and settling behavior of whole-tailings particles in deep-cone thickener

Rapid dewatering and thickening of whole-tailings with ultrafine particles is one of the most important processes for the whole-tailings paste preparation. Deep-cone thickener, a kind of such process for the flocculation and settling of whole-tailings, is particularly necessary to study. However, there exist many problems in observing the flocculation and settling process of whole-tailings, as well as the particle size distribution (PSD) of whole-tailings floccules in deep-cone thickener. Population balance model (PBM) is applied to predict the PSD in deep-cone thickener, and LUO model and GHADIRI model are employed to study the aggregation and fragmentation mechanism of the whole-tailings particles, respectively. Through three-dimensional numerical simulation on the whole-tailings flocculation and settling in deep-cone thickener using computational fluid dynamics (CFD)-PBM, the distribution of density and turbulent kinetic energy in deep-cone thickener were obtained, at the same time the spatio-temporal changes of whole-tailings floccules particle size distribution are analyzed. Finally, the major flocculation position in deep-cone thickener is found and the flocculation settling rules of whole-tailings are achieved.
Influence factors on stress corrosion cracking of P110 tubing steel under CO_2 injection well annulus environment

Stress corrosion cracking (SCC) behavior of P110 tubing steel in simulated CO_2 injection well annulus environments was investigated through three-point bent tests, potentiodynamic polarization and EIS measurements. The results demonstrate that SCC of P110 tubing steel could occur in acidulous simulated environment, and the sensitivity of SCC increases with the decrease of pH, as well as increase of sulfide concentration and total environmental pressure. Both anodic dissolution and hydrogen embrittlement make contributions to the SCC. Adequate concentration of corrosion inhibitor can inhibit the occurrence of SCC on account of the inhibition of localized anodic dissolution and cathodic hydrogen evolution.
A novel coordinated control strategy considering power smoothing for a hybrid photovoltaic/battery energy storage system

This work presents a novel coordinated control strategy of a hybrid photovoltaic/battery energy storage (PV/BES) system. Different controller operation modes are simulated considering normal, high fluctuation and emergency conditions. When the system is grid-connected, BES regulates the fluctuated power output which ensures smooth net injected power from the PV/BES system. In islanded operation, BES system is transferred to single master operation during which the frequency and voltage of the islanded microgrid are regulated at the desired level. PSCAD/EMTDC simulation validates the proposed method and obtained favorable results on power set-point tracking strategies with very small deviations of net output power compared to the power set-point. The state-of-charge regulation scheme also very effective with SOC has been regulated between 32% and 79% range.
Mass transfer enhancement for LiBr solution using ultrasonic wave

The methods were studied to improve the cooling performance of the absorption refrigeration system (ARS) driven by low-grade solar energy with ultrasonic wave, while the mechanism of ultrasonic wave strengthening boiling mass transfer in LiBr solution was also analyzed with experiment. The experimental results indicate that, under the driving heat source of 60–100 oC and the ultrasonic power of 20–60 W, the mass flux of cryogen water in LiBr solution is higher after the application of ultrasonic wave than auxiliary heating with electric rod of the same power, so the ultrasonic application effectively enhances the heat utilization efficiency. The distance H from ultrasonic transducer to vapor/liquid interface significantly affects mass transfer enhancement, so an optimal H_(opt) corresponding to certain ultrasonic power is beneficial to reaching the best strengthening effect for ultrasonic mass transfer. When the ultrasonic power increases, the mass transfer obviously speeds up in the cryogen water; however, as the power increases to a certain extent, the flux reaches a plateau without obvious increment. Moreover, the ultrasound-enhanced mass transfer technology can reduce the minimum temperature of driving heat source required by ARS and promote the application of solar energy during absorption refrigeration.
Characteristics analysis and library development for piezoelectric transformer to drive a ballast for a 35 W class fluorescent lamp using PSPICE modeling

PSPICE model driven by an electric equivalent circuit of a piezoelectric circuit is presented. In order to confirm this model to be effective, an independent model of cold cathode fluorescent lamp (CCFL) driving circuit is used to conduct simulations, leading to a precise modeling. A library is configured through modeling and its accuracy is verified through simulations for widely used and representative lamps such as CCFL, fluorescent lamps, HID lamps, and electrodeless fluorescent lamps. On the basis of experiments, a lamp simulation is also performed using PSPICE, which allows us to take advantage of the lamp library easily. Also, PSPICE model driven by an electric equivalent circuit of a piezoelectric transformer is presented. In order to confirm this model to be effective, an independent model of CCFL driving circuit is used to conduct simulations, leading to a precise modeling. In addition, a new type of electronic ballast is proposed, which allows 35 W-class (T5-class) fluorescent lamp to work. This system is built by a rectifier which has improved power factor and half-bridge series resonant inverter. Also, with size of 27.5 mm high, 27.5 mm wide and 2.5 mm thick, the produced piezoelectric transformer has a high step-up ratio, through which it is possible for the electric ballast circuit to be lighter, smaller and more efficient. After the produced ballast is used to drive the fluorescent lamp for 25 min, it yields 0.95 in power factor correction, 86% in efficiency, 35.07 W in output voltage and 20.5 °C in temperature increase while meeting the characteristics of the 35 W-class fluorescent lamp.
Simultaneous separation and determination of four main isoflavonoids in Astragali Radix by an isocratic LC/ESI-MS method

A simple, reliable and rapid isocratic liquid chromatography (LC)-mass spectrometric detection (MS) coupled with electrospray ionization (ESI) method for simultaneous separation and determination of calycosin-7-O-β-D-glucoside, ononin, calycosin and formonometin in Astragali Radix was developed. After the samples were extracted with ethanol, the optimum separation conditions for these analytes were achieved using water and acetonitrile (70:30, v/v) containing 0.2% (v/v) acetic acid as a mobile phase and a 2.0 mm×150 mm Hypersil-Keystone C_(18) column. Selective ion monitoring (SIM) mode and [M+H]~+ ions at m/z 447, 431, 285 and 269 were used for quantitative analysis of four main active components above mentioned. The calibration curves were linear in the range of 0.4–175.0 μg/mL for calycosin-7-O-β-D-glucoside, 0.2–146.0 μg/mL for ononin, 0.4–210.0 μg/mL for calycosin and 0.5–217.0 μg/mL for formonetion, respectively. The limits of quantification (LOQ) and detection (LOD) were 0.4 μg/mL and 0.08 μg/mL for calycosin-7-O-β-D-glucoside, 0.2 μg/mL and 0.06 μg/mL for ononin, 0.4 μg/mL and 0.1 μg/mL for calycosin, 0.5 μg/mL and 0.1 μg/mL formonetion, respectively. The standard recoveries were in the range of 96.5%–104.7%. The developed method has successfully been used for the determination of four main flavonoids in Astragali Radix from various sources and can be used for identification, differentiation and quality evaluation of Astragali Radix.
Invasion by alligator weed, Alternanthera philoxeroides, is associated with decreased species diversity across the latitudinal gradient in China

Aims Invasive species occurrence and their effects on biodiversity may vary along latitudes. We examined the occurrence (species cover) and relative dominance (importance value) of invasive alligator weed, Alternanthera philoxeroides, in its terrestrial habitat in China through a large-scale latitudinal field investigation. Methods We established 59 plots along the latitudinal transect from 21°N to 37°N. We recorded species name, abundance, height and individual species coverage of plants in every quadrat. We then measured α-species diversity variations associated with the A. philoxeroides community across the latitudinal range. We also analyzed the effect of latitude on plant species' distributions in this community by using canonical correspondence analysis (CCA). Important Findings We found that species cover and importance value of A. philoxeroides increased in areas <35°N, but decreased at higher latitudes. Lower latitudes supported greater species diversity than higher latitudes. Small-scale invasion of A. philoxeroides was associated with higher species diversity, but community diversity was lower when A. philoxeroides species cover exceeded 36%. Community plant species changed from mesophyte to hygrophyte gradually from low to high latitude. Our research suggests that latitude had significant influences on community diversity which interacted with the biotic resistance of a community and impact of invasion. Consequently, A. philoxeroides may become more invasive and have greater negative impacts on community species diversity in higher latitudes as global climate changes.
阿托伐他汀短期治疗对高血压合并腔隙性脑梗死伴血脂异常患者血清内脏脂肪特异性丝氨酸蛋白酶抑制剂水平的影响

目的观察高血压合并腔隙性脑梗死伴血脂异常患者脂肪细胞因子--内脏脂肪特异性丝氨酸蛋白酶抑制剂(Vaspin)水平的变化,并探讨阿托伐他汀短期治疗对血清Vaspin水平的影响。方法连续入选2015年1-6月于内科门诊就诊并诊断为高血压合并腔隙性脑梗死伴血脂异常的初诊患者128例为治疗组,同期体检健康人群112人为对照组。治疗组患者在常规服用降压药基础上加用阿托伐他汀20 mg/d,1次/d,治疗时间4周。用酶联免疫吸附试验(ELISA)法检测治疗组患者治疗前后血清Vaspin水平。结果治疗前,与对照组比较,治疗组患者诊室血压、总胆固醇、三酰甘油、低密度脂蛋白胆固醇(LDL-C)和高敏C反应蛋白(hsCRP)水平明显升高,而高密度脂蛋白胆固醇(HDL-C)和血清Vaspin水平明显降低(均P<0.05)。阿托伐他汀治疗4周后,治疗组患者血压、总胆固醇、三酰甘油、LDL-C和hsCRP水平明显下降,HDL-C和血清Vaspin水平明显升高(均P<0.05)。Pearson相关性分析显示,血清Vaspin水平与收缩压(r=-0.45)、舒张压(r=-0.40)、总胆固醇(r=-0.56)、三酰甘油(r=-0.67)、LDL-C(r=-0.63)和hsCRP(r=-0.53)呈负相关,与HDL-C(r=0.55)呈正相关(均P<0.05)。校正血压和血脂后,多元逐步回归分析显示,hsCRP是血清Vaspin水平的影响因素(β=-1.07,P<0.05)。结论阿托伐他汀短期治疗能提高高血压合并腔隙性脑梗死伴血脂异常患者的血清Vaspin水平。
中国养老金融行业现状及发展

养老金融或养老金金融指养老金理论与金融学理论结合形成的新兴交叉学科,主要研究养老金在金融市场投资,以实现自身保值增值,同时促进金融市场发展的理论和实践问题 。本文在介绍国内外学相关领域的理论研究基础上,归纳总结了近年来中国学界对于我国养老金融行业发展状况及未来方向的观点讨论。
目标导向性液体治疗对老年急性胆囊炎术后患者血清超氧化物歧化酶、丙二醛水平及免疫功能的影响

目的探讨目标导向性液体治疗对老年急性胆囊炎术后患者血清超氧化物歧化酶(SOD)、丙二醛(MDA)与免疫功能的影响。方法选取该院2013年8月至2014年8月接收的70例老年急性胆囊炎患者,随机分为实验组(n=35)与对照组(n=35),实验组在手术过程中行目标导向性液体治疗,对照组在手术过程中行常规液体治疗。比较两组手术前后血清SOD、MDA与免疫功能的变化情况。结果两组血清SOD水平均有所下降,但实验组下降程度低于对照组(P<0.05);而术后两组患者的MDA水平均上升,且对照组的上升程度大于实验组(P<0.05);两组患者手术后的T淋巴细胞水平较手术前均有所提高,且实验组CD3~+、CD4~+、CD8~+水平变化较显著(P<0.05)。结论目标导向性液体治疗应用于老年急性胆囊炎,能够减轻患者术后的氧化应激反应,进而提高患者的免疫功能,有利于患者术后的恢复。
单腔气管插管CO_2人工气胸法在全腔镜食管癌根治术中的安全性和可行性

目的对比单腔气管插管CO_2人工气胸法与双腔气管插管法在全腔镜食管癌根治术中对病人呼吸、循环的影响,并进行术中安全可行性评估及术后并发症对比。方法选择行全腔镜食管癌根治术患者120例,年龄39~70岁,美国麻醉师协会(ASA)Ⅰ~Ⅲ级,男女不限。采用随机数字表法分为两组:单腔气管导管组(S组)和双腔支气管导管组(D组),每组60例。收集心率(HR)、平均动脉压力(MAP)、血氧分压(SpO_2)、气道峰压(Ppeak)、呼气末二氧化碳分压(PETCO_2)、血气分析等呼吸、循环指标,采集麻醉诱导前(T1)、插管定位成功后20 min(T2)、右肺萎陷20 min(T3)、60 min(T4)、鼓肺双肺通气后30 min(T5)的数据,计算肺内分流率(Qs/Qt)。结果S组T3、T4点pH值显著降低(P<0.05),PaCO_2、PETCO_2、PaO_2均显著高于D组(P<0.05),而Qs/Qt升高均明显低于D组(P<0.05);S组插管成功率高,导管定位时间、咽喉及气管黏膜损伤、术后声嘶、喉痛的发生率低于D组(P<0.05)。结论单腔气管插管CO_2人工气胸法可用于大多数食管癌根治术患者。
不同剂量阿托伐他汀对老年冠心病合并心房颤动患者超敏C反应蛋白、白细胞介素-6、肿瘤坏死因子-α、脂联素水平及预后的影响

目的探讨不同剂量阿托伐他汀对老年冠心病合并心房颤动患者血清超敏C反应蛋白(hs-CRP)、白细胞介素(IL)-6、肿瘤坏死因子(TNF)-α、脂联素(APN)水平及预后的影响。方法选择2013年10月至2015年10月在该院收治的冠心病合并心房颤动老年患者120例,随机分为阿托伐他汀大剂量组和阿托伐他汀小剂量组各60例。大剂量组患者于常规治疗基础上加服阿托伐他汀钙20 mg/d,1次/d;小剂量组患者加服阿托伐他汀钙10 mg/d,1次/d,两组患者均连续接受治疗6个月。比较两组患者治疗前后的心房利尿钠肽(ANP)、左心房前后径(LAD)、hs-CRP、IL-6、TNF-α及APN水平。记录并比较两组患者治疗6个月后栓塞事件发生率和窦性心律维持率。结果治疗前,两组患者血清hs-CRP、IL-6、TNF-α及APN水平无统计学差异(P>0.05);治疗后,两组hs-CRP、IL-6及TNF-α水平均明显低于治疗前,血清APN水平明显高于治疗前(P<0.05),同时大剂量组各指标变化明显优于小剂量组(P<0.05)。治疗前,两组患者LAD和ANP比较无统计学差异(P>0.05);治疗后两组均明显低于治疗前(P<0.05),同时大剂量组降低明显大于小剂量组(P<0.05)。治疗后,大剂量组患者栓塞事件发生率明显低于小剂量组、窦性心律维持率明显高于小剂量组(P<0.05)。结论大剂量阿托伐他汀能明显降低老年冠心病合并心房颤动患者的血清炎症因子、LAD内径及ANP水平,改善预后,安全性好,值得临床上推广。
左心室重量指数对老年左室射血分数正常心力衰竭的诊断价值

目的评价左心室重量指数(LVMI)对老年左心室射血分数(LVEF)正常心力衰竭(HFNEF)患者的诊断价值。方法选择2014年1~12月于该院心内科诊断为心功能不全的患者,年龄≥60岁,心功能分级Ⅱ~Ⅳ级,入院24 h内行超声心动图检查共232例,根据心脏超声结果中的LVEF分为HFNEF组158例(LVEF≥45%)和LVEF降低的心衰(HFREF)组74例(LVEF≤40%),并选取同期健康对照组100例。对入选对象进一步搜集超声心动图中收缩末期左房内径(LAD)、舒张末期左室内径(LVEDd)、室间隔厚度(IVST)、左室后壁厚度(LVPWT),血液常规检查,在常规超声心动图的基础上计算出LVMI。结果①与健康对照组相比,心力衰竭组LVEDd、IVST和LVPWT均升高(P<0.05);与HFREF 组相比,HFNEF组IVST和LVPWT增大(P<0.05);LVEDd、E/A较HFREF组减小(P<0.05);②以LVMI>122 g/m~2(女性),LVMI>149 g/m~2(男性)为临界值,诊断HFNEF 的灵敏度(男性18.7%,女性47.9%)、特异度(男性96%,女性99%);HFNEF 患者中,LVMI随NYHA 心功能分级的恶化而升高,在各级心功能分级之间差异显著(P<0.05)。结论LVMI检测可作为诊断心衰的方法之一,可提高对老年HFNEF患者诊断。
沙格列汀降低自发性高血压大鼠血压的效果及作用机制

目的探讨沙格列汀降低自发性高血压大鼠(SHR)血压的效果及作用机制。方法选择30只SHR,按随机数字表法分为干预组和对照组(n=15),同时选择15只Wistar-Kyoto(WKY)大鼠作为WKY组。干预组大鼠每日给予剂量为10 mg/kg的沙格列汀灌胃处理,同期给予对照组及WKY组等体积的超纯水,均持续8 w。以无创伤血压测定仪测量三组大鼠处理前后的尾动脉收缩压(SBP),测量间期2 w;显微镜下观察主动脉的病理形态学变化;分别采用放射免疫法、酶联免疫法、硝基还原法检测血浆中的胰高血糖素样肽(GLP)-1、内皮素(ET)-1和一氧化氮(NO)水平。结果(1)干预组SBP随处理时间的延长逐渐降低,而对照组逐渐升高,且干预组处理后的SBP均低于同期对照组,而仍高于同期WKY组(P<0.05)。(2)显微镜下观察显示,对照组和干预组均表现不同程度的平滑肌细胞增生肥大、内膜增厚,但干预组较对照组有所改善。(3)8 w后干预组大鼠的血浆GLP-1水平均显著高于WKY组及对照组(P<0.05);对照组和干预组的ET-1水平较WKY组明显升高,NO水平明显降低,而干预组ET-1水平低于对照组,NO水平高于对照组(P<0.05)。结论沙格列汀可降低SHR的动脉血压,其机制可能与抑制ET-1的释放、促进NO的合成有关。
加速康复外科理念在精准肝切除治疗肝细胞癌中的应用策略

肝切除是肝细胞癌(简称肝癌)最主要的治疗手段之一,随着肝脏外科手术技术提高、影像学的发展以及肝脏储备功能评估方法的进步,业已进入精准肝切除时代。精准肝切除不仅倡导外科技术的精细准确,而且注重以肝病和肝切除相关病理和生理状态为依据指导术前评估和围手术期处理,旨在实现以最小创伤侵袭、最大器官保护、最低医疗耗费、获得最佳治疗效果的理想目标。加速康复外科(enhanced recovery after surgery,ERAS)是基于循证医学证据的一系列围手术期优化处理措施,控制围手术期病理生理学反应,减少手术创伤和术后应激,实现外科术后充分止痛、早期活动以及促进器官功能恢复,从而减少术后并发症、促进病人康复、缩短住院时间以及节省医疗费用。迄今为止,国内外对精准肝切除治疗肝癌的ERAS研究尚处于临床探索和经验积累阶段,缺乏可供临床应用的标准策略。本文旨在为目前正在或即将开展精准肝切除治疗肝癌ERAS研究的同道提供参考作用。
Robust adaptive control for dynamic systems with mixed uncertainties

The control problem for single-input single-output (SISO) systems in the presence of mixed uncertainties, both stochastic and deterministic uncertainties, is considered. The stochastic uncertainties are modeled as exogenous noises, while the deterministic uncertainties are time invariant and appear as the unknown parameters which lie in a bounded interval. Based on a subdivision for the continuous interval, a robust adaptive controller is designed. The controller can not only realize the system output to track the desired output, but also learn a more accurate interval which contains the true value of the unknown parameter with a learning error given in advance. An example is given finally to demonstrate the effectiveness of the proposed method.
The behavior of cesium adsorption on zirconyl pyrophosphate

Zirconyl pyrophosphate (ZrP_2O_7) was prepared and Cs adsorption behavior was studied. Results show that the distribution coefficient of Cs adsorption on ZrP_2O_7 was about 2800 mL/g. Ion exchange capacity of ZrP_2O_7 was 0.35 mmol/g. In dynamic tests, Cs can be separated from other fission products very well by ZrP_2O_7. The ZrP_2O_7 was stable both at high temperatures and in high concentration of nitric acid. The Cs adsorption by ZrP_2O_7 is a monolayer and chemical adsorption.
A comprehensive study for mass attenuation coefficients of different parts of the human body through Monte Carlo methods

The gamma-ray mass attenuation coefficients of blood, bone, lung, eye lens, adipose, tissue, muscle, brain and skin were calculated at different energies (60, 80, 150, 400, 500, 600, 1000, 1250, 1500, and 2000 keV) by various theoretical methods such as FLUKA, GEANT4 Monte Carlo (MC) methods and XCOM program in this work. Calculated coefficients were also compared with theNational Institute of Standards and Technology (NIST) values. Obtained results were highly in accordance with each other and NIST values. Our results showed that FLUKA was quite convenient in comparison to GEANT4 in the calculation of themass attenuation coefficients of the used human body samples for low-energy photons (60, 80, and 150 keV) when compared with the NIST values.
A new non-specificity measure in evidence theory based on belief intervals

In the theory of belief functions, the measure of uncertainty is an important concept, which is used for representing some types of uncertainty incorporated in bodies of evidence such as the discord and the non-specificity. For the non-specificity part, some traditional measures use for reference the Hartley measure in classical set theory; other traditional measures use the simple and heuristic function for joint use of mass assignments and the cardinality of focal elements. In this paper, a new non-specificity measure is proposed using lengths of belief intervals, which represent the degree of imprecision. Therefore, it has more intuitive physical meaning. It can be proved that our new measure can be rewritten in a general form for the non-specificity. Our new measure is also proved to be a strict non-specificity measure with some desired properties. Numerical examples, simulations, the related analyses and proofs are provided to show the characteristics and good properties of the new non-specificity definition. An example of an application of the new nonspecificity measure is also presented.
Motion synchronization in a dual redundant HA/EHA system by using a hybrid integrated intelligent control design

This paper presents an integrated fuzzy controller design approach to synchronize a dissimilar redundant actuation system of a hydraulic actuator (HA) and an electro-hydrostatic actuator (EHA) with system uncertainties and disturbances. The motion synchronous control system consists of a trajectory generator, an individual position controller for each actuator, and a fuzzy force tracking controller (FFTC) for both actuators. The trajectory generator provides the desired motion dynamics and designing parameters of the trajectory which are taken according to the dynamic characteristics of the EHA. The position controller consists of a feed-forward controller and a fuzzy position tracking controller (FPTC) and acts as a decoupled controller, improving position tracking performance with the help of the feed-forward controller and the FPTC. The FFTC acts as a coupled controller and takes into account the inherent coupling effect. The simulation results show that the proposed controller not only eliminates initial force fighting by synchronizing the two actuators, but also improves disturbance rejection performance.
让科学与传播同行

科学传播首先要影晌有影响力的人虽然说“知识就是力量”,并且这种力量“不仅取决于其本身价值的大小,更取决于它是否被传播以及传播的广度和深度”,但是科学并不是天然地受到普通公众的喜欢,同时公众对科学的兴趣有余而信任不足,特别是体制性信任欠缺,这便会导致科学的传播受到一定的阻碍,因为公众科学知识的多寡和他们对科学的理解之间并非存在直接的线性关系,相反,信任在公众理解科学中发挥着重要的作用,公众倾向于从信任的渠道和信任的专家那里获取科技信息。另外一方面,对于大众媒体来说,和其他话题相比,科学议题也不必然会受到更高的重视,因为“科学记者并没有把教育公众视为他们的责任”,“他们既不会忠实或者热衷于来自作为科学事业的新闻,也不会忠实或者热衷于来自某一个领域的科学的新闻”,同时由于存在着议程设置和框架理论,编辑部会把科学新闻纳入到自己的框架中,从而决定了公众应该怎么想,虽然它们无法决定公众会想什么。但是传播是科学的“本质”,只有传播才能让科学的作用发挥出来,当然这种传播不仅仅局限于小同行之间的传播,更应该扩展到面向全体公众的传播,同时也只有通过传播,才能让科学研究成果的“酒香”飘出深巷,进而服务于全人类的福祉。
非经典Wnt信号通路在心脏发育和干细胞向心肌分化中的作用机制

Wnt信号通路是一种哺乳动物进化保守的信号通路,在心脏发育和干细胞向心肌细胞分化中发挥重要的调控作用。经典Wnt信号通路主要调控早期心肌谱系提交,而非经典Wnt信号通路参与调控后续的心脏发育和分化。本文对非经典Wnt信号通路在心脏发育和干细胞向心肌细胞分化中的作用及其机制作一综述,以期为干细胞移植治疗缺血性心肌病提供参考策略。
An Examination of Some Factory Physics Principles

In this paper, we examine some principles in managing manufacturing systems. These principles are concerned with the variability, the utilization, the rework, the lead time, and the constant work-in-process efficiency. While these principles are developed through analyzing some simpler disconnected flow line manufacturing systems, we examine whether they can have broad applications. For some of these principles, we provide sufficient conditions, while for others, we provide counterexamples. Our analysis suggests that we should be very cautious about these laws when applied to non-Markov and non-tandem systems.
结核性脊髓炎临床特征分析及诊断(附4例报告)

结核性脊髓炎是中枢神经系统结核感染中比较少见的类型,临床表现不典型,诊断缺乏特异性。2010年1月至2015年7月第二军医大学长海医院共收治第一诊断为结核性脊髓炎的患者4例。本研究总结分析了结核性脊髓炎的临床特点、脑脊液及影像学表现,以期为其早期诊断及治疗提供依据。
单一煤储层煤层气直井合理日产气量的确定

确定单一煤储层煤层气直井合理日产气量可为煤层气井布井及经济评价提供依据。根据等温吸附、水气启动压力梯度流动等理论,建立了单一煤储层条件下煤层气直井合理日产气量的数理模型,研究了平均日产气量与主控影响因素间的关系。研究表明:渗透率、临储压力比与平均日产气量呈指数形式变化;含气饱和度与平均日产气量呈线性关系。沁水盆地中南部煤层气实际排水采气资料与预测结果的对比验证了模型的准确性。该研究结果为现场煤层气直井选址及经济评价提供了理论依据。
新型热采筛管在海上稠油油田的应用

海上热采井井底温度达300 ℃,高温热应力加剧了出砂风险,筛管作为最后一道屏障,决定着热采防砂的成败。筛管在高温、腐蚀和强注强采的恶劣环境下易发生损坏,导致油井出砂停产。针对海上热采井生产特点,研发了新型热采筛管。该筛管材质选用热稳定性强、耐腐蚀和强度高的P110H-3Cr钢材;结构优化为7层,内外2层挡砂网精度外大内小,逐层过滤;特殊结构的导流外护套,减少高速流体冲蚀影响。新型热采筛管不仅具备较好的热稳定性能,而且提高了抗腐蚀能力。截至2015年12月,新型热采筛管已成功应用15井次,作业成功率为100%,单井产能提高2~3倍,未发生出砂及筛管损坏情况。该技术满足了海上油田热采防砂要求,为提高热采效果奠定了基础。
低渗透油藏水驱注采压差优化研究

针对渤南五区低渗透油藏储层非均质性强、剩余油分布复杂、水驱动用程度差异大的问题,以五点法井网为例,根据流线分布特征,将井网划分为多个计算单元,利用流管法计算得到各个计算单元水驱开发指标。以均衡驱替为目标,以各计算单元内的注采压差为优化变量,综合考虑储层物性及剩余油分布的非均质性,应用优化算法,得到了各计算单元的最优注采压差。研究表明,各计算单元的剩余油饱和度差异越大,达到均衡驱替时要求的时间越短,各调控单元所需的注采压差相差也越大。数值模拟结果表明,该注采压差优化方法能够明显减少各分区的剩余油分布差异,提高采收率2.6%。研究成果可有效指导低渗透水驱油藏开发决策的制订。
致密砂岩气藏主要产气阶段渗流特征

针对致密砂岩气藏渗透率极低,导致其渗流规律复杂的问题,以压裂直井非稳态渗流阶段的渗流特征为基础,运用渗流力学分析方法、叠加原理和渐进分析手段,得到分段压裂水平井非稳态时期水平井日产气量倒数与生产时间呈线性关系的产能方程及单井产能预测中"拐点"的判别方法。结合现场生产数据,验证了公式的正确性。研究成果表明,分段压裂水平井主要产气阶段渗流为非稳态渗流,为致密砂岩气藏现场开采的产能预测、"死气区"优化及单井控制储量优化提供理论基础。以西加盆地B气藏为例,研究成果使单井产能预测误差降低至1.74%。研究成果对致密砂岩气藏的开发策略及开发方案编制具有指导意义。
海上层状油藏油井水驱采出程度预测

针对S油田目标井组水驱期间油井采出程度差异大的问题,运用统计学方法,研究影响采出程度的主要因素。通过建立多元线性回归模型,进行敏感性分析,筛选出影响采出程度的主要因素为油井产水量、油井有效厚度、主力层地层系数。通过拟合得到油井水驱采出程度的经验公式,利用所得经验公式对目标井组相邻油井进行采出程度预测,计算出的采出程度与实际值较为接近,精确度为0.96。研究成果为预测海上层状油藏油井水驱采出程度提供了有效途径,为油田后续措施的实施提供了理论依据。
惠州凹陷地层压力特征及演化史

珠江口盆地惠州凹陷是已证实的富烃凹陷,但与油气成藏密切相关的地层压力场研究较少。以惠州凹陷现今压力场特征及单井超压演化历史的研究为基础,应用2D盆地模拟方法,对惠州凹陷地层压力演化进行了模拟恢复,探讨了压力演化与构造运动的关系。研究结果表明:惠州凹陷地层压力经历了2.5个"增压-泄压"旋回,包括始新世末(44.0~34.0 Ma)旋回、早渐新世(34.0~23.8 Ma)旋回及晚渐新世至今(23.8~0.0 Ma)半旋回。现今地层在深层恩平组及文昌组泥岩发育超压带,构造演化导致压力演化的旋回性。揭示与油气成藏关系密切的压力特征有利于该区勘探目标的优选。
塔中高-特高含凝析油凝析气藏注水驱油研究

通过建立凝析油最大反凝析速度判别方法,对不同相态凝析气藏凝析油析出速度变化特征进行分析,准确判定了近井地带凝析油的反凝析程度。在此基础上,通过精细裂缝-基质双重介质凝析气藏数值模拟模型,对塔中I号气田II区洞穴型、缝洞型高-特高含凝析油凝析气藏注水驱油效果进行了研究,分析了凝析油反凝析程度、水侵模式、裂缝物性及发育程度、裂缝与基质耦合程度和注水速度对气藏储层系统注水驱油效果的影响。研究表明,反凝析程度严重且注入水可形成强能量次生边底水的凝析气藏,具有强油水置换能力,适合注水驱油开发,注水驱油机理分析与现场先导试验结果一致。研究结果为塔中裂缝性双重介质储层高-特高含凝析油凝析气藏中后期增产方案的制订提供了依据。
巴楚北部寒武系沉积相及储层特征评价

为认识巴楚北部储层的展布规律,综合岩心、测井及地震等资料,对寒武系沉积相特征进行了分析。结果表明:局限台地相、蒸发台地相及开阔台地相是该区寒武系发育的主要沉积相类型,3种台地类型在时间上互相演化,以局限台地相发育的云坪、灰云坪微相为较好相带。主要储集空间包括次生作用形成的孔隙及溶蚀孔洞、裂缝;上寒武统白云岩晶体间的微孔隙、晶体间的溶蚀孔隙、溶蚀孔洞以及裂缝比较发育,半充填与未充填占比大,孔隙度较低,渗透率稍高,孔渗相关性不大,受裂缝控制,总体上表现为优势储层。储层发育的主控因素为沉积、成岩及构造运动,沉积相是优势储层发育的先决条件;成岩及构造作用能较好改善储层物性,白云石化是储层形成的重要条件。上寒武统的储层储集性好,主要为Ⅰ-Ⅱ类储层,为优势储层发育区。研究结果为该区的储层评价及油气勘探有利区域的选择提供有效指导。
孤北洼陷浊积水道砂体预测与岩性油气藏勘探

针对孤北洼陷沙三段9砂岩组重力流浊积水道砂体预测问题,依据重力流沉积过程响应,对重力流沉积开展了期次划分与对比,将重力流自旋回划分为重力流势能向上减弱的退积旋回以及势能向上增强的进积旋回。浊积水道砂体发育于沉积不整合面之上的退积旋回之中,其在地震上主要表现为沿沉积不整合面之上的沟谷充填特征,据此将浊积水道砂体限定于等时地层格架之中。依据浊积水道砂体的地震响应特征,通过提取地震振幅厚度属性,预测了浊积水道砂体的分布。预测结果表明,浊积水道砂体不仅是形成岩性圈闭的有利储层,而且对油气分布具有重要的控制作用,是孤北洼陷开展岩性油气藏勘探的有利目标。该研究为孤北洼陷岩性油气藏的勘探指明了方向。
大邑构造雷口坡组四段天然气成藏条件

以区域地质研究为基础,通过三维地震解释及有机地球化学分析等技术手段,综合分析了大邑构造雷口坡组四段天然气成藏条件及其勘探潜力。研究结果表明,大邑地区二叠系及雷口坡组烃源岩发育,深大断裂及不整合面可作为油气运移的良好通道,天然气成藏具有"双源供烃"的良好气源条件。雷口坡组四段发育台缘滩沉积,基质孔渗性较好,加之后期风化淋滤及构造变形,推断发育孔隙-缝洞复合型优质储层。发育于构造轴部的1号断鼻圈闭面积大、幅度高,具备良好的封盖及保存条件。雷口坡组四段圈闭、储层形成时间早,具有"下生上储式"、"自生自储式"良好的生储盖组合,是川西雷口坡组天然气勘探的一个新的有利目标。
深度老龄化背景下中国养老机构发展困境与对策

由于老龄化速度严重超前于社会经济发展水平,导致我国在养老、医疗、长期照料服务和公共资源分配等相关社会管理和社会政策体系都处在"未富先老"、"未备先老"状态,养老机构在监督与管理制度建设、服务质量与服务内容管理、养老床位以及专业护理人员供需等方面仍存在着较多问题。
中药牛膝化学成分、药理作用及储藏保管

牛膝又称怀牛膝,系苋科多年生草本植物牛膝Achyranthes bidentataBl.的干燥根,始载于《神农本草经》,列为上品。其味苦、酸,性平。归肝、肾经,具有逐瘀通经,补肝肾,强筋骨,利尿通淋,引血下行功效,主产河南武陟、温县、泌阳等地,是闻名国内外的"四大怀药"之一〔1〕。本文着重综述近年来牛膝的化学成分、药理作用及储藏保管的研究进展,以期为其临床用药的有效性提供参考。
Testing and modeling of rockfill materials: A review

The research development of rockfill materials (RFM) was investigated by a series of large-scale triaxial tests. It is observed that confining pressure and particle breakage play important roles in the mechanical property, dilatancy relation and constitutive model of RFM. In addition, it is observed that the conventional dilatancy relation and constitutive model are not suitable for RFM due to the complex mechanical behavior. Hence, it needs to propose a unified constitutive model of RFM, considering the statedependent and particle breakage behavior.