Wellbore Cleaning Degree and Hydraulic Extension in Shale Oil Horizontal Wells

The efficient development and exploitation of shale oil depends on long-distance horizontal wells. As the degreeof cleaning of the wellbore plays a key role in these processes, in this study, this problem is investigated experimentallyby focusing on the dimensionless cuttings bed height. A method is proposed to calculate the horizontalwellhydraulic extension taking into account the influence of the wellbore cleaning degree on the wellborepressure distribution and assess the effect of a variety of factors such as the bottom hole pressure, the circulatingpressure drop, the drilling pump performance and the formation properties. The analysis shows that the hydraulicextension of horizontal wells decreases with an increase in the cuttings bed height, and the higher the displacementof drilling fluid, the faster the hydraulic extension declines. The annular pressure drop of the horizontalsection increases with the increase of the cuttings bed height, resulting in a higher bottom-hole pressure. Severalarguments are provided to guide the safe drilling of shale oil horizontal wells and overcome the limits of currenttechnological approaches.

Overview of Factors Affecting Dust Deposition on Photovoltaic Cells and Cleaning Methods

Dust deposition on the surface of photovoltaic (PV) cells poses a significant challenge to their efficiency, especially in arid regions characterized by desert and semi-desert conditions. Despite the pronounced impact of dust accumulation, these regions offer optimal solar radiation and minimal cloud cover, making them ideal candidates for widespread PV cell deployment. Various surface cleaning methods exist, each employing distinct approaches. Choosing an appropriate cleaning method requires a comprehensive understanding of the mechanisms involved in both dust deposition on module surfaces and dust adhesion to PV cell surfaces. The mechanisms governing dust deposition and adhesion are complex and multifaceted, influenced by factors such as the nature and properties of the dust particles, environmental climatic conditions, characteristics of protective coatings, and the specific location of the PV installation. These factors exhibit regional variations, necessitating the implementation of diverse cleaning approaches tailored to the unique conditions of each location. The first part of this article explores the factors influencing dust deposition on PV cell surfaces, delving into the intricate interplay of environmental variables and particle characteristics. Subsequently, the second part addresses various cleaning methods, offering an analysis of their respective advantages and disadvantages. By comprehensively examining the factors influencing dust accumulation and evaluating the effectiveness of different cleaning strategies, this article aims to contribute valuable insights to the ongoing efforts to optimize the performance and longevity of photovoltaic systems in diverse geographical contexts.

Data cleaning method for the process of acid production with flue gas based on improved random forest

Acid production with flue gas is a complex nonlinear process with multiple variables and strong coupling.The operation data is an important basis for state monitoring,optimal control,and fault diagnosis.However,the operating environment of acid production with flue gas is complex and there is much equipment.The data obtained by the detection equipment is seriously polluted and prone to abnormal phenomena such as data loss and outliers.Therefore,to solve the problem of abnormal data in the process of acid production with flue gas,a data cleaning method based on improved random forest is proposed.Firstly,an outlier data recognition model based on isolation forest is designed to identify and eliminate the outliers in the dataset.Secondly,an improved random forest regression model is established.Genetic algorithm is used to optimize the hyperparameters of the random forest regression model.Then the optimal parameter combination is found in the search space and the trend of data is predicted.Finally,the improved random forest data cleaning method is used to compensate for the missing data after eliminating abnormal data and the data cleaning is realized.Results show that the proposed method can accurately eliminate and compensate for the abnormal data in the process of acid production with flue gas.The method improves the accuracy of compensation for missing data.With the data after cleaning,a more accurate model can be established,which is significant to the subsequent temperature control.The conversion rate of SO_(2) can be further improved,thereby improving the yield of sulfuric acid and economic benefits.

Investigation of a facile plasma-driven method for in situ cleaning of metal-based contamination

Self-cleaning of tin contaminants was realized utilizing a self-driven hydrogen plasma.Cleaning rates of 0.7-6 nm min-1were achieved for removal of discontinuous tin particles at different powers.The analysis of topography and cross-sectional morphology revealed that the removal of tin particles was achieved through top-down cleaning with hydrogen plasma,where the upper part of spherical tin particles was always more intensely cleaned under the synergistic effect of hydrogen atoms and ions due to the vertical incidence of ions to the substrate during the whole cleaning process.Redeposition of tin atoms caused by physical sputtering and its promotion of the chemical cleaning effect was observed for the first time.Reflectance recovery measurements during cleaning and surface analysis of the substrate after cleaning indicated that nondestructive cleaning with a reflectance loss of less than 1%can be achieved at a relatively low power of120 W.Plasma-induced substrate damage,such as holes and valleys,reduced the reflectance of the substrate when cleaning was performed at a high power greater than 120 W,so this method should only be considered for application under conditions without substrate exposure.This study provides a comprehensive understanding of the removal of discontinuous tin particles using the in situ self-driven plasma cleaning method,and also provides meaningful guidance for the extension of this method in other potential fields of application.

Scheduling a Single-Arm Multi-Cluster Tool With a Condition-Based Cleaning Operation

As wafer circuit widths shrink less than 10 nm,stringent quality control is imposed on the wafer fabrication processes. Therefore, wafer residency time constraints and chamber cleaning operations are widely required in chemical vapor deposition, coating processes, etc. They increase scheduling complexity in cluster tools. In this paper, we focus on scheduling single-arm multi-cluster tools with chamber cleaning operations subject to wafer residency time constraints. When a chamber is being cleaned, it can be viewed as processing a virtual wafer. In this way, chamber cleaning operations can be performed while wafer residency time constraints for real wafers are not violated. Based on such a method, we present the necessary and sufficient conditions to analytically check whether a single-arm multi-cluster tool can be scheduled with a chamber cleaning operation and wafer residency time constraints. An algorithm is proposed to adjust the cycle time for a cleaning operation that lasts a long cleaning time.Meanwhile, algorithms for a feasible schedule are also derived.And an algorithm is presented for operating a multi-cluster tool back to a steady state after the cleaning. Illustrative examples are given to show the application and effectiveness of the proposed method.

Study of Oil-Bearing Drill Cuttings Cleaning and De-Oiling Treatment Method for Shale Gas Reservoirs

Due to its extensive use in shale gas exploration and development,oil-based drilling fluids generate large amounts of oil-bearing drill cuttings during the drilling process.The large amount of oil-bearing drill cuttings generated during the drilling process can lead to serious secondary contamination.In this study,a wetting agent FSC-6 with good hydrophobic and oleophobic properties was synthesized to construct an efficient oil removal system.For the first time,the mechanism of this system was analyzed by using the theory of adhesion function,interfacial tension and wettability.At the same time,a combined acoustic-chemical treatment process was applied to the wastewater and slag generated after the cleaning of the oil-bearing drill cuttings.The experimental results show that the application of this pollution-free technology can effectively solve the environmental pollution and resource recovery problems of oil-bearing drill cuttings.It meets the standard of drilling chips with oil content less than 2%in SY/T7422-2018“Oil-based drilling fluid drilling chips treatment system for oil and gas drilling equipment”.

Cleaning of Multi-Source Uncertain Time Series Data Based on PageRank

There are errors in multi-source uncertain time series data.Truth discovery methods for time series data are effective in finding more accurate values,but some have limitations in their usability.To tackle this challenge,we propose a new and convenient truth discovery method to handle time series data.A more accurate sample is closer to the truth and,consequently,to other accurate samples.Because the mutual-confirm relationship between sensors is very similar to the mutual-quote relationship between web pages,we evaluate sensor reliability based on PageRank and then estimate the truth by sensor reliability.Therefore,this method does not rely on smoothness assumptions or prior knowledge of the data.Finally,we validate the effectiveness and efficiency of the proposed method on real-world and synthetic data sets,respectively.

Hydraulic modeling and optimization of jet mill bit considering the characteristics of depressurization and cuttings cleaning

A jet mill bit(JMB)is proposed to increase the drilling efficiency and safety of horizontal wells,which has the hydraulic characteristics of depressurization and cuttings cleaning.This paper fills the gap in the hydraulic study of the JMB by focusing on the hydraulic modeling and optimization of the JMB and considering these two hydraulic characteristics.First,the hydraulic depressurization model and the hydraulic cuttings cleaning model of the JMB are developed respectively.In the models,the pressure ratio and efficiency are chosen as the evaluation parameters of the depressurization capacity of the JMB,and the jet hydraulic power and jet impact force are chosen as the evaluation parameters of cuttings cleaning capacity of the JMB.Second,based on the hydraulic models,the effects of model parameters[friction loss coefficient,target inclination angle,rate of penetration(ROP),flow ratio,and well depth]on the hydraulic performance of the JMB are investigated.The results show that an increase in the friction loss coefficient and target inclination angle cause a significant reduction in the hydraulic depressurization capacity,and the effect of ROP is negligible.The flow ratio is positively related to the hydraulic cuttings cleaning capacity,and the well depth determines the maximum hydraulic cuttings cleaning capacity.Finally,by combining the hydraulic depressurization model and hydraulic cuttings cleaning model,an optimization method of JMB hydraulics is proposed to simultaneously maximize the jet depressurization capacity and the cuttings cleaning capacity.According to the drilling parameters given,the optimal values of the drilling fluid flow rate,backward nozzle diameter,forward nozzle diameter,and throat diameter can be determined.Moreover,a case study is conducted to verify the effectiveness of the optimization method.

Effect of a disposable endoscope precleaning kit in the cleaning procedure of gastrointestinal endoscope:A multi-center observational study

BACKGROUND Precleaning is a key step in endoscopic reprocessing.AIM To develop an effective and economic endoscope cleaning method by using a disposable endoscope bedside precleaning kit.METHODS Altogether,228 used gastrointestinal endoscopes were selected from five high-volume endoscopy units and precleaned by a traditional precleaning bucket(group T)or a disposable endoscope bedside precleaning kit(group D).Each group was further subdivided based on the replacement frequency of the cleaning solution,which was replaced every time in subgroups T1 and D1 and every several times in subgroups Ts and Ds.The adenosine triphosphate(ATP)level and residual proteins were measured three times:Before and after precleaning and after manual cleaning.RESULTS After precleaning,the precleaning kit significantly reduced the ATP levels(P=0.034)and has a more stable ATP clearance rate than the traditional precleaning bucket.The precleaning kit also saved a quarter of the cost of enzymatic detergent used during the precleaning process.After manual cleaning,the ATP levels were also significantly lower in the precleaning kit group than in the traditional precleaning bucket group(P<0.05).Meanwhile,the number of uses of the cleaning solution(up to four times)has no significant impact on the cleaning effect(P>0.05).CONCLUSION Considering its economic cost and cleaning effect,the use of a disposable endoscope bedside precleaning kit can be an optimal option in the precleaning stage with the cleaning solution being replaced several times in the manual cleaning stage.

Effects of Househould Cleaning Methods on Carbendazim Residue in Apples

Carbendazim,belonging to fungicides,was commonly used for controlling crop diseases,resulting in frequent residues in fruits and vegetables.Washing was the initial step of household fruit processing for cleaning and reducing pollutant contents.However,the effect of washing on the removal of carbendazim in apples was not systemically studied.Thus,in this study,an analytical method was firstly established for the determination of carbendazim with great accuracy and precision through quick,simple,cheap,effective and safe(QuEChERS)method and ultra-performance liquid chromatography-fluorescence detection(UPLC-FLD).Then,the influencing factors were systematically researched to unveil their effects on the carbendazim residue in apples.The results indicated that water temperature,washing products and washing method could obviously affect the carbendazim content in apples.In addition,the best cleaning scheme for removal of carbendazim was soaking apples for 5 min in a cleaning solution,which was prepared by dissolving 8 g of commercial fruit washing soup with 500 ml of water at 45℃.Under this condition,the removal rate of carbendazim in the washing step reached 73.91%.This study will be helpful for providing guidance for household cleaning methods for controlling pesticide residues.

基于Edem-RecurDyn联合仿真的火车皮厢底冻黏浮煤清扫机构性能优化分析

火车皮作为煤炭运输的主要设备之一,其运输效率一直是煤炭运输行业的关注重点,在北方地区冬季低温条件下,影响运输效率的主要原因是煤炭中所含的水分与凹凸不平的车厢内表面形成黏附,逐渐由车厢表层向煤炭内部扩散,最终产生冻车现象导致设备无法继续运行。首先,以不同清扫方式现存的问题为出发点,结合实际的工程项目,设计了一款自动化冻黏浮煤清扫机构并对其清扫性能进行优化研究。其次,通过理论研究分析建立浮煤冻黏颗粒模型,分析清扫过程中滚刀的运动情况并建立力学模型和数学模型。最后,联合多体动力学软件RecurDyn对清扫机构底部清扫滚筒性能进行仿真研究,求解不同滚筒转速、牵引速度和清扫深度对清扫性能的影响规律,通过优化寻求清扫阻力最小、能耗最低的性能参数匹配方案。结果表明,清扫机构的清扫效率受滚筒转速影响较小,随滚筒转速提高,清扫阻力大小在一定范围内波动;随着牵引速度不断提高,清扫阻力先降低后逐渐增高;清扫深度对清扫阻力的影响最大,随清扫深度的增加,其清扫阻力不断增加。根据单因素参数对清扫阻力大小影响规律,取合理范围利用响应面法对其综合影响规律进行仿真试验,得到目标函数后,利用Matlab对其数学模型求解最优解,最终得到滚筒转速为78 r/min、牵引速度为0.05 m/s、清扫深度为100 mm时,清扫机构所受阻力最小、清扫比能耗最低为0.22 kWh/m^(3),清扫机构性能达到最优。

化学药品中的遗传毒性杂质的质量控制

药品中微量水平的遗传毒性物质具有引发肿瘤甚至癌症的风险,并且该致癌风险可能与剂量没有相关性。因此,目前各国监管机构要求对药品中遗传毒性杂质进行严格控制。本综述通过查阅国内外相关文献、指导原则,从监管机构对药品中遗传毒性杂质的监管策略、遗传毒性杂质来源、检测方法及清除策略4个方面进行了系统的总结综述。该综述为药品中遗传毒性杂质的控制/清除、检测提供了参考和依据。

基于超疏水、超亲水自清洁涂层的研究及其多功能应用

固体材料因其表面积聚的灰尘、污垢、油脂等污染物而受到污染,进而导致材料的失效和故障等问题。通过涂覆超亲水、超疏水的特殊润湿性自清洁涂层是解决这些问题的有效方法。从固体表面润湿性理论出发,阐述了理论润湿模型、润湿性参数以及润滑行为;介绍了超疏水性、超亲水性自清洁功能的工作原理。同时,介绍了国内外关于超疏水、超亲水自清洁涂层的相关制备方法及其优缺点,以及涂层在光伏发电、防冰防霜、金属防腐领域的多功能应用。最后指出,存在对涂层稳定性、抗脱落性等综合性能的评估不足,缺乏对适用环境因素的考量等问题,并对其研究前景进行了展望。

亲清政商关系与企业数字化转型

在数字经济时代,数字化转型是企业实现高质量发展的内生要求,而企业的数字化转型离不开政府的引导和支持。基于此,分析检验当前亲清政商关系构建会如何影响微观企业的数字化转型,有助于企业实现高质量发展。利用2016—2020年中国A股传统行业上市公司的年度观察数据研究发现,亲清政商关系对企业数字化转型具有显著的正向影响,即在政商关系越亲清的地区,企业的数字化水平越高,并且这种正向影响在非国有企业中表现得更强。进一步的机制检验表明,亲清政商关系主要通过“市场导向效应”和“资源供给效应”对企业数字化转型发挥积极的促进作用。更具有启发意义的是,主要是政商关系的“亲近化”而不是政商关系的“清白化”助力了企业的数字化转型,而且亲清政商关系能够降低传统政治关联的相关影响。

穴位按摩在电子结肠镜检查前肠道准备中干预效果的研究

目的观察穴位按摩对行电子结肠镜检查前肠道准备的干预效果。方法选取2021年7月至2022年7月待行电子结肠镜检查者300例,按照随机数字表法分为2组,对照组150例予常规肠道准备干预,研究组150例在对照组基础上联合穴位按摩干预。比较2组检查时肠道清洁度情况,比较2组干预后即刻、肠道准备时及结肠镜检查时舒适度视觉模拟评分法(VAS)评分情况,比较2组干预前后心理状态焦虑自评量表(SAS)评分及抑郁自评量表(SDS)评分情况,比较2组检查后应激反应指标舒张压(DBP)、收缩压(SBP)及心率(HR)情况。结果研究组检查时肠道清洁优良率95.33%(143/150),对照组肠道清洁优良率77.33%(116/150),研究组的肠道清洁优良率高于对照组(P<0.05)。研究组干预后即刻、肠道准备时及结肠镜检查时舒适度VAS评分均低于对照组(P<0.05)。与本组干预前比较,2组干预后心理状态SAS评分及SDS评分均降低(P<0.05),且研究组干预后SAS评分及SDS评分均低于对照组(P<0.05)。研究组检查后应激反应指标SBP、DBP及HR水平均低于对照组(P<0.05)。结论穴位按摩对行电子结肠镜检查者的肠道准备干预效果显著,可明显提高肠道准备质量,提高患者舒适度,缓解焦虑、抑郁情绪,减轻机体应激反应。

两种方法清洗消毒达芬奇机器人手术臂的效果比较

目的探讨达芬奇机器人手术臂有效的清洗消毒方法。方法回顾性分析2022年1月至2023年4月江西省人民医院手术室使用后的达芬奇机器人手术臂200件达芬奇机器人手术臂作为研究对象,按照不同的操作流程将其分为观察组(100件)与对照组(100件)。观察组采用流动水冲洗+腹腔镜酶剂浸泡+超声波清洗机超声+蒸汽清洗机清洗手术臂操作端+高压水枪纯水漂洗+全自动清洗机清洗消毒。对照组清洗消毒流程为流动水冲洗+腹腔镜酶剂浸泡+超声波清洗机超声+刷洗手术臂操作端+高压水枪纯水漂洗+全自动清洗机清洗消毒。采用目测检查法(四倍带光源放大镜)、腺苷三磷酸(ATP)生物荧光快速检测法进行检测,计算清洗质量不合格的返洗率,比较两组的清洗消毒操作平均耗时。结果观察组的目测检查法返洗率低于对照组,观察组的ATP生物荧光检测返洗率低于对照组,差异有统计学意义(P<0.05)。观察组清洗消毒平均耗时短于对照组,差异有统计学意义(P<0.05)。结论蒸汽清洗机清洗消毒达芬奇机器人手术臂效果比手工刷洗清洗消毒效果更为理想,可节约大量清洗消毒时间,有效节约稀有医疗资源。

我国24家检验检测机构洁净环境照度检测能力验证

目的评价我国检验检测机构对洁净环境照度的检测能力。方法回顾性分析中国食品药品检定研究院于2022年在全国范围内首次设计并组织实施的洁净环境照度能力验证项目。基于洁净环境检测的行业特点,该项目分为笔试和实际操作(简称实操)两部分。笔试部分,共3题(限时40 min完成),考察参加测试(简称参测)实验室对检测标准正确理解和掌握的程度,根据专家商议确定的评分标准评分(满分50分)。实操部分,以该院药用辅料和包装材料检定所的2台洁净工作台为现场考核样品,以参测实验室的现场测试结果考察参测实验室的仪器操作和实验水平(限时5 min完成),以Z值进行评价(︱Z︱≤2,>2~<3,≥3分别为满意、有问题、不满意)并打分(满分50分)。以笔试和实操评分之和评价参测实验室的检测能力(≥60分为合格)。结果共24家实验室参加了能力验证并按要求提交了结果报告。笔试,评分为45~50分,满分21家(87.50%)。实操,样品A,满意21家(87.50%),有问题3家(12.50%);样品B,满意23家(95.83%),有问题1家(4.17%),2个样品均无不满意的实验室。24家实验室总评分均合格。结论该次能力验证结果显示,各实验室的检测能力维持良好,但部分实验室存在对标准的理解和掌握仍有欠缺或未按校准周期对照度计进行计量等问题,建议检测人员加深对洁净环境检测标准的理解,相应机构重视仪器的校准,持续提高检测能力。

基于HACCP的6S管理在精神病专科医院保洁管理中的应用

目的探讨危害分析及关键控制点(HACCP)联合6S管理法在精神病专科医院保洁管理中的应用效果。方法采用方便抽样方法,于2023年3月-6月,选取山东省某三级甲等精神病专科医院的30名病区保洁人员作为研究对象,采用基于HACCP的6S管理进行干预,并进行自身前后对照比较分析。结果基于HACCP的6S管理的实施,使保洁人员的医院感染基础知识、个人防护与职业暴露知晓率有所提升(P均<0.05),明显改善了保洁人员的手卫生正确性和依从性(P均<0.05),环境清洁消毒情况得到改善(P均<0.05),住院患者护理满意度和护理人员对保洁人员的满意度均得到提升。结论通过6S管理的标准化模式识别危险因素,将关键环节的评估、预防和控制工作融入保洁管理中,并进行同质化干预,能够提高保洁管理水平,对提升医患双方满意度有一定促进作用。

US/PS技术协同处理天然气管道污物试验及中试研究

该文针对天然气输送管道产生的清洗污水及受污染膜组件,采用超声耦合过硫酸盐处理技术,将污水及固废物协同处理,并搭建了撬装式中试处理装置.实验结果表明:当过硫酸盐加入量为0.33 mol·L^(-1)、初始pH值为4.0、超声功率为840 W、过硫酸盐投加次数为5次时,在反应6 h后COD去除率为80.08%.在协同处理膜组件后,出水水质及膜组件浸出液浓度均能满足排放标准,现场中试结果表明:处理效果持续稳定,撬装装置可结合生产实际间歇式运行,最佳条件核算成本为168.3元·m^(-3).

咀嚼型洁齿骨活性成分体外抑菌试验和临床应用效果评估

为了评估咀嚼型洁齿骨对成年犬口腔健康状况的改善情况及其主要活性成分的体外抑菌效果,本试验采用牛津杯法定性检测咀嚼型洁齿骨中主要活性成分对变异链球菌、粘性放线菌、嗜酸乳杆菌、牙龈卟啉单胞菌和具核梭杆菌具核亚种的抑菌活性;并选取30只临床健康成年犬,经超声波洁牙后,随机分为3个组,对照组正常饲喂,试验1组和试验2组分别添加不同品牌的洁齿骨,每间隔30 d由同一名兽医对试验犬的牙菌斑、牙结石和牙龈炎进行医学评分并测定犬口气值。结果显示:咀嚼型洁齿骨中活性成分茶多酚、厚朴酚、杜仲提取物、金银花提取物、溶菌酶和保鲜复合酶对5种口腔常见致病菌的生长抑制效果相对较好;洁牙后90 d,试验1组和试验2组犬牙菌斑和牙结石评分均显著低于对照组(P<0.05);洁牙后30和90 d,试验2组犬牙龈炎评分显著低于对照组(P<0.05);与对照组相比,洁牙后饲喂咀嚼型洁齿骨明显改善了犬口臭情况,试验2组犬口气测定值均低于试验1组,差异不显著(P>0.05)。结果表明,咀嚼型洁齿骨一定程度上可以缓解犬口腔健康状况,且添加活性成分的洁齿骨效果相对较好。