Bridge Plug Drillouts Cleaning Practices—An Overview

Horizontal fracture-simulated completions remain the most reliable method of producing hydrocarbons from shale formations. The vast majority of unconventional wells are completed using the “Plug and Perf” method. This method involves using either a coiled tubing (CT) with a positive displacement motor or a jointed pipe to mill out composite plugs after fracturing operations are completed. An estimated average of 120,000 composite plugs is installed in the US alone each year. Bridge plug drillouts from milling operations tend to accumulate in horizontal wells and can cause stuck pipe incidents and loss of well control. Efficient removal of composite plugs’ debris is crucial in achieving operational efficacies and full production potential. This paper provides an overview of the various bridge plug drillouts cleaning practices adopted in horizontal wells. It discusses several case histories, showcasing how operators solved cleanout challenges. Developed mechanistic models to better understand hole cleaning are also reviewed. As more unconventional wells are being set at more extensive depths, an economical and optimized coiled tubing process becomes increasingly important. This paper focuses on delivering a more conclusive set of recommendations to increase efficiency and improve current composite plug coiled tubing cleaning-milling practices, increase operational efficiency and reduce cost.

Electrocatalytic CO_(2)reduction to syngas

While carbon dioxide(CO_(2))is a major greenhouse gas,it is also an important C1 resource.In the trend of energy conservation and emission reduction,electrocatalytic reduction has become a very promising strategy for CO_(2)utilization because it can convert CO_(2)directly to high-valued chemicals and fuels under mild conditions.In particular,the product CO and by-product H_(2)can be combined into syngas by an electrocatalytic CO_(2)reduction reaction(CO_(2)RR)in an aqueous medium.Different molar ratios of CO and H_(2)may be used to produce essential bulk chemicals or liquid fuels such as methanol,alkanes,and olefins through thermochemical catalysis,Fischer-Tropsch synthesis,microbial fermentation,and other techniques.This work discusses the latest strategies in controlling the molar ratio of CO/H_(2)and improving the yield of CO_(2)RR-to-syngas.The challenges of electrocatalytic syngas production are analyzed from an industrial application perspective,and the possible measures to overcome them are proposed in terms of new catalyst design,electrolyte innovation,flow reactor optimization,anodic reaction coupling,and operando technique application.

Research on the navigation method of large-scale differential tail-control improvised guided munitions based on rotational speed constraints

In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this problem, this paper describes a new system of guided ammunition based on tail spin reduction. After analyzing the mechanism of the ammunition's tail spin reduction, a navigation method of large scale difference tail control simple guided ammunition based on speed constraint is proposed. In this method,the corresponding navigation constraints can be carried out by combining the rotation speed state of the ammunition itself, and the optimal solution of navigation parameters during the flight of the missile can be obtained by Extended Kalman Filter(EKF). Finally, the performance of the proposed method was verified by the simulation environment, and the hardware-in-the-loop simulation test and flight test were carried out to verify the performance of the method in the real environment. The experimental results show that the proposed method can achieve the optimal estimation of navigation parameters for simple guided ammunition with large-scale difference tail control. Under the conditions of simulation test and hardware-in-loop simulation test, the position and velocity errors calculated by the method in this paper converged. Under the condition of flight test, the spatial average error calculated by the method described in this paper is 6.17 m, and the spatial error of the final landing point is 3.50 m.Through this method, the accurate acquisition of navigation parameters in the process of projectile launching is effectively realized.

Summary Analysis of National Surveillance on Kashin-Beck Disease from 1990 to 2023

Objective To analyze the epidemiological characteristics and epidemic situation of children with Kashin-Beck disease(KBD)in China,and provide the basis for formulating prevention and control measures.Methods Fixed-point monitoring,moving-point monitoring,and full coverage of monitoring were promoted successively from 1990 to 2023.Some children(7-12 years old)underwent clinical and right-hand X-ray examinations every year.According to the KBD diagnosis criteria,clinical and X-ray assessments were used to confirm the diagnosis.Results In 1990,the national KBD detectable rate was 21.01%.X-ray detection decreased to below 10%in 2003 and below 5%in 2007.Between 2010 and 2018,the prevalence of KBD in children was less than 0.4%,which fluctuated at a low level,and has decreased to 0%since 2019.Spatial epidemiological analysis indicated a spatial clustering of adult patients prevalence rate in the KBD areas.Conclusion The evaluation results of the elimination of KBD in China over the last 5 years showed that all villages in the monitored areas have reached the elimination standard.While the adult KBD patients still need for policy consideration and care.

Interfacial reinforcement of core-shell HMX@energetic polymer composites featuring enhanced thermal and safety performance

The weak interface interaction and solid-solid phase transition have long been a conundrum for 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane(HMX)-based polymer-bonded explosives(PBX).A two-step strategy that involves the pretreatment of HMX to endow—OH groups on the surface via polyalcohol bonding agent modification and in situ coating with nitrate ester-containing polymer,was proposed to address the problem.Two types of energetic polyether—glycidyl azide polymer(GAP)and nitrate modified GAP(GNP)were grafted onto HMX crystal based on isocyanate addition reaction bridged through neutral polymeric bonding agent(NPBA)layer.The morphology and structure of the HMX-based composites were characterized in detail and the core-shell structure was validated.The grafted polymers obviously enhanced the adhesion force between HMX crystals and fluoropolymer(F2314)binder.Due to the interfacial reinforcement among the components,the two HMX-based composites exhibited a remarkable increment of phase transition peak temperature by 10.2°C and 19.6°C with no more than 1.5%shell content,respectively.Furthermore,the impact and friction sensitivity of the composites decreased significantly as a result of the barrier produced by the grafted polymers.These findings will enhance the future prospects for the interface design of energetic composites aiming to solve the weak interface and safety concerns.

A Novel Clutter Suppression Algorithm for Low-Slow-Small Targets Detecting Based on Sparse Adaptive Filtering

Passive detection of low-slow-small(LSS)targets is easily interfered by direct signal and multipath clutter,and the traditional clutter suppression method has the contradiction between step size and convergence rate.In this paper,a frequency domain clutter suppression algorithm based on sparse adaptive filtering is proposed.The pulse compression operation between the error signal and the input reference signal is added to the cost function as a sparsity constraint,and the criterion for filter weight updating is improved to obtain a purer echo signal.At the same time,the step size and penalty factor are brought into the adaptive iteration process,and the input data is used to drive the adaptive changes of parameters such as step size.The proposed algorithm has a small amount of calculation,which improves the robustness to parameters such as step size,reduces the weight error of the filter and has a good clutter suppression performance.

Expression of triggering receptor-1 in myeloid cells of mice with acute lung injury

BACKGROUND： Myeloid cell （TREM-1） is an important mediator of the signal transduction pathway in inflammatory response. In this study, a mouse model of acute lung injury （ALl） by intraperitoneal injection of lipopolysaccharide （LPS） was established to observe the expression pattern of TREM-1 in lung tissue and the role of TREM-1 in pulmonary inflammatory response to ALl.METHODS： Thirty BALB/C mice were randomly divided into a normal control group （n=6） and an ALl group （n=24）. The model of ALl was made by intraperitonal injection of LPS in dose of 10 mg/ kg. Specimens from peripheral blood and lung tissue were collected 6, 12, 24 and 48 hours after LPS injection. RT-PCR was used to detect TREM-1 mRNA, and ELISA was employed for detection of TREM-1 protein and TNF-a protein, and HE staining was performed for the pathological Smith lung scoring under a light microscope.RESULTS： The expressions of TREM-1 mRNAin lung tissue and blood of the ALl group 6, 12, 24, and 48 hours after injection of LPS were higher than those in the control group. The levels of TREM- 1 protein and the levels of TNF-a protein in lung tissue of the ALl group 6, 12, 24, and 48 hours after LPS injection were higher than those of the control group; the level of TREM-1 protein peaked 12 hours after LPS injection, but it was not significantly correlated with the expression of TREM-1 mRNA （P=0.14）; the TNF-a concentration was positively correlated with TREM-1 levels in lung tissue and with Smith pathological score （r=0.795, P=0.001 ：r=0.499, P=0.034）, but not with the expression of TREM-1 mRNA （P=0.176）.CONCLUSION： The expression of TREM-1 mRNA in lung tissue of mice with ALl is elevated, and the expression of TREM-1 mRNA is related to the level of TNF-a and the severity of inflammatory response to ALl. The expressions of the TREM-1 gene are not consistent with the levels of TREM-1 protein, suggesting a new functional protein involved in immune regulation.

RPH、外剥内扎术联合肛垫悬吊及皮桥整形术治疗中老年女性脱垂性环状痔的临床观察

目的探讨以自动痔疮套扎术(RPH)、外剥内扎术(M-M)为基础的肛垫悬吊及皮桥整形术治疗中老年女性脱垂性环状痔的临床疗效。方法选取2018年1月—2019年1月于遂宁市中心医院就诊的124例中老年女性脱垂性环状痔患者,随机分为对照组和观察组,每组62例。对照组患者采用RPH、M-M治疗,观察组患者采用RPH、M-M联合肛垫悬吊、皮桥整形术治疗。观察两组患者手术时间、术中出血量及住院时间等手术相关指标;比较两组患者术后第4天便时出血、创面疼痛、肛缘水肿评分等临床症状;比较两组患者术后1个月治疗有效率;比较两组患者术后3个月肛缘皮赘形成、肛门直肠狭窄、肛门形态。结果观察组手术时间较对照组长(P<0.05)。观察组创面疼痛、便时出血、肛门坠胀、肛缘水肿评分较对照组低(P<0.05)。观察组治疗总有效率较对照组高(P<0.05)。观察组肛缘皮赘形成、肛门形态评分较对照组低(P<0.05)。结论RPH、M-M联合肛垫悬吊、皮桥整形术可显著减轻老年女性脱垂性环状痔患者黏膜及外痔脱垂症状,降低患者便时出血、创面疼痛及肛缘水肿程度,减少术后肛缘皮赘形成,适合临床推广。

Non-Intrusive Load Identification Model Based on 3D Spatial Feature and Convolutional Neural Network

Load identification method is one of the major technical difficulties of non-intrusive composite monitoring. Binary V-I trajectory image can reflect the original V-I trajectory characteristics to a large extent, so it is widely used in load identification. However, using single binary V-I trajectory feature for load identification has certain limitations. In order to improve the accuracy of load identification, the power feature is added on the basis of the binary V-I trajectory feature in this paper. We change the initial binary V-I trajectory into a new 3D feature by mapping the power feature to the third dimension. In order to reduce the impact of imbalance samples on load identification, the SVM SMOTE algorithm is used to balance the samples. Based on the deep learning method, the convolutional neural network model is used to extract the newly produced 3D feature to achieve load identification in this paper. The results indicate the new 3D feature has better observability and the proposed model has higher identification performance compared with other classification models on the public data set PLAID.

血清Hcy对不稳定型心绞痛患者焦虑症发生的影响

目的探讨血清同型半胱氨酸(Hcy)水平对不稳定型心绞痛患者焦虑症发生的影响。方法纳入150例不稳定型心绞痛患者作为研究对象,采用焦虑自评量表(SAS)对其焦虑症进行调查,根据结果分为无焦虑组和焦虑组。抽取空腹肘正中静脉血2 ml检测Hcy,分析Hcy水平对焦虑症的影响。结果 150例不稳定型心绞痛患者中出现焦虑症68例,占45.3%。两组患者年龄、SAS评分、病程及Hcy水平比较,差异有统计学意义(P<0.05)。病程延长及Hcy水平升高是影响不稳定型心绞痛患者焦虑症的独立危险因素。轻度组Hcy水平及高同型半胱氨酸血症(HH)比例与中、重度组比较,差异有统计学意义(P<0.05);中度组Hcy水平及HH比例与重度组比较,差异有统计学意义(P<0.05)。相关性分析结果表明,Hcy水平随SAS评分增加而升高(P<0.05)。结论血清Hcy水平是不稳定型心绞痛患者焦虑症发生的危险因素,且与焦虑症严重程度呈正相关。临床上对存在血清Hcy水平升高的不稳定型心绞痛患者需要密切注意其情绪变化。

Overview of Precious Metal Content Analysis Methods in Automotive Catalytic Converter

With the increasing awareness of environmental protection, people’s concern of pollution issues arising. Vehicles, as the most important means of transportation, its exhaust emission has received considerable attention. The catalytic converter is able to purify harmful substances in exhaust gas. The absolute content of precious metals in the catalytic converter dominates the exhaust gas purification effect. Accurate detection of precious metal content is of great significance for controlling the cost of catalysts, ensuring catalytic performance and recovering precious metals from spent catalysts. We herein summarized several instruments for precious metals content exploration, such as X-ray fluorescence spectrometer (XRF), atomic absorption spectrometer (AAS), inductively coupled plasma emission spectrometer (ICP) and spectrophotometer. In this thesis, the feasibility of using various devices for characterizing precious metal content in catalytic converters is analyzed and their strengths or weaknesses are elaborated.

The Application of Computed Tomography Angiography in Aortic Dissection

Aortic dissection (AD) is a life-threatening clinical emergency requiring rapid diagnosis and effective intervention to improve patient survival and prognosis. Computed tomography angiography (CTA) can be used to diagnose AD accurately and quickly, making it the first choice for diagnosing AD in an emergency. This article reviews the application of CTA in the diagnosis and treatment of AD.

Analysis of Metallographic Characteristics of Aluminum Alloy for Turbocharged Impellers

In this paper, the composition, two-dimensional and three-dimensional microstructure of heat-resistant wrought aluminum alloy with strong oxidation resistance, heat resistance and easy processing are analyzed by using direct reading spectrometer, metallographic microscope and scanning electron microscope. The main alloy elements of heat-resistant forging aluminum alloy include Cu, Mg, Si, Ni and Fe. The α solid solution of each element in aluminum consists of S phase (Al2CuMg), Mg2Si phase, bright gray Al2CuNi phase and dark brown Al9FeNi phase. The distribution of each phase in the aluminum alloy is determined by the three-dimensional energy spectrum analysis of the microstructure, and the distribution of each phase in the crystal position is analyzed. The mechanism of heat resistance, easy processing type and wear resistance is obtained, which provides the theoretical basis for the development and use of heat-resistant forged aluminum alloy.

烟碱对腹腔感染败血症小鼠的保护作用及其机制研究

目的探讨烟碱激活胆碱能抗炎通路对败血症的保护作用及其机制。方法采用盲肠结扎并穿孔(CLP)法复制败血症模型。65只健康昆明小鼠分为对照组、CLP组和烟碱400μg/kg组,记录CLP后24、36和48 h的生存率。另取18只小鼠分组同上,CLP后20 h计算肺湿干重比、败血症严重程度评分,行肝、肺组织病理学检查。另取120只小鼠随机分为对照组、CLP组,以及烟碱400、200和40μg/kg组,酶联免疫吸附法检测CLP后1、2、4和6 h血浆TNF-α和IL-1β的浓度。结果术后24、36和48 h,烟碱400μg/kg组生存率较CLP组升高(P<0.05);术后20 h烟碱400μg/kg组肺湿干重比和败血症严重程度评分较CLP组降低(P<0.05),肝、肺组织病理改变较CLP组减轻。术后2、4和6 h,烟碱400、200和40μg/kg组血浆TNF-α浓度较CLP组降低(P<0.05);术后1和6 h,烟碱400、200和40μg/kg组血浆IL-1β浓度较CLP组降低(P<0.05)。烟碱400μg/kg组血浆TNF-α浓度在术后2 h低于40μg/kg组(P<0.05),术后6 h低于200和40μg/kg组(P<0.05)。并术后2和4 h烟碱200μg/kg组血浆TNF-α浓度较40μg/kg组降低(P<0.05)。术后4 h烟碱400μg/kg组血浆IL-1β浓度低于200和40μg/kg组(P<0.05)。结论烟碱减轻腹腔严重感染小鼠败血症严重程度,改善肝、肺的病理组织学变化,降低机体促炎症细胞因子水平,提高生存率。

自我录像示范干预学龄初期儿童课堂学业自立的个案研究

为了探讨自我录像示范对学龄初期儿童课堂学业自立养成的影响,研究采用单个被试的A-B实验设计,用自我录像示范对一名学龄初期儿童的课堂学业自立进行干预。结果表明:自我录像示范的干预能提高个案的课堂学业自立水平,在干预期和追踪期出现高课堂学业自立行为的频次均高于基线期。结论:自我录像示范能够促进学龄初期儿童课堂学业自立的养成。儿童对于示范录像中目标行为的习得和运用可以泛化到日常生活中类似的其他情境中,且情景越相似,效果越佳。

移动互联网在教学改革与创新中的应用

目前,传统教学手段呈现教学内容的方式机械、教学的交流方式单一,制约了学习活动的生机与活力,导致了学习活动的枯燥、教学质量的低下.而基于移动终端和无线互联网的移动互联网已经给传统教育带来变革,这种变革也必将对高校教学产生影响.通过开发一个基于Andriod系统的辅助教学移动平台的实例,提示高校应该以一个积极的姿态迎接技术变革带来的挑战,主动进行教学改革,将移动互联网技术广泛应用于日常教学生活当中.

Prognostic nutritional index predicts postoperative complications and long-term outcomes of gastric cancer

AIM: To investigate the impact of prognostic nutritional index (PNI) on the postoperative complications and long-term outcomes in gastric cancer patients undergoing total gastrectomy.

姬塬油田储层注水伤害分析与化学增注技术研究

姬塬油田属特低渗油田,在注水开发过程中,因注入水与地层水严重不配伍,导致储层孔喉结垢,影响油田注水开发。本文通过对注入水与地层水分析、水管路流动结垢实验、注水储层伤害评价等,认为注入水与地层水不配伍是造成储层伤害的主要原因之一。开发了能够溶解硫酸钡锶垢的YHS-1清垢剂,有效解除储层结垢堵塞,恢复储层渗透率。

Positive impact of adding No.14v lymph node to D2 dissection on survival for distal gastric cancer patients after surgery with curative intent

Background： D2 lymphadenectomy has been increasingly regarded as standard surgical procedure for advanced gastric cancer （GC）, while the necessity of No.14v lymph node （14v） dissection for distal GC is still controversial. Methods： A total of 920 distal GC patients receiving at least a D2 lymph node dissection in Department of Gastric Cancer, Tianjin Medical University Cancer Institute and Hospital were enrolled in this study, of whom, 243 patients also had the 14v dissected. Other 677 patients without 14v dissection were used for comparison. Results： Forty-five （18.5%） patients had 14v metastasis. There was no significant difference in 3-year overall survival （OS） rate between patients with and without 14v dissection. Following stratified analysis, in TNM stages I, II, IIIa and IV, 14v dissection did not affect 3-year OS; in contrast, patients with 14v dissection had a significant higher 3-year OS than those without in TNM stages IIIb and IIIc. In multivariate analysis, 14v dissection was found to be an independent prognostic factor for GC patients with TNM stage IIIb/IIIc disease [hazard ratio （HR）, 1.568; 95% confidence interval （CI）： 1.186-2.072; P=0.002]. GC patients with 14v dissection had a significant lower locoregional, especially lymph node, recurrence rate than those without 14v dissection （11.7 % vs. 21.1%, P=0.035）. Conclusions： Adding 14v to D2 lymphadenectomy may be associated with improved 3-year OS for distal GC staged TNM IIIb/IIIc.

Effect of co-transfection of miR-520c-3p and miR-132 on proliferation and apoptosis of hepatocellular carcinoma Huh7

Objective:To investigate the effects of co-transfection of miR-520c-3p and miR-132 on proliferation and apoptosis of hepatocellular carcinoma Huh7.Methods:Hepatocellular carcinoma Huh7 was cultured in vitro and lipidosome was used to transfect miR-520c-3p and miR-132 respectively or together.The effects of transfection of miR-520c-3p and miR-132 on proliferation and apoptosis of Huh7 were detected by CCK8 and Annexin V staining and flow cytometry,and the expression level of the targeted gene of over-expressed miR-520c-3p and miR-132 was determined by Western blot and realtime PCR.Results:Compared with the control group,the proliferation ability of Huh7 of the single transfected and co-transfected miR-520c-3p and miR-132 decreased significantly,and the apoptosis ratio increased distinctly(P<0.05).Besides,the affect of the co-transfection group was better than that of the single transfection group.The protein levels of GPC3(Glypican-3) and YAP(Yes-associated protein),the target genes transfected only by miR-520c-3p and miR-132,respectively,reduced obviously(P<0.05),which was similar with the co-infected cells,but cells transfected by miR-132 only showed a decrease of YAP.Conclusions:The co-transfection of miR-520c-3p and miR-132 can target-regulate the expression of GPC3 and YAP,enhance the exhibition effect on proliferation of hepatocellular carcinoma Huh7 and induce cell apoptosis synergistically.