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Wellbore-heat-transfer-model-based optimization and control for cooling downhole drilling fluid

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Petroleum Science 2024年第3期21卷 1955-1968页

作者： Chao Wang He Liu Guo-Wei yu Chen yu xian-Ming Liu peng Huang Yangtze University Jingzhou434023HubeiChina State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China CNPC Bohai Drilling Engineering Co. LtdTianjin300280China Exploration Development and Construction Engineering Division of PetroChina Jidong Oilfield Company Tangshan63200HebeiChin Henan University of Urban Construction Pingdingshan467036HenanChina

To address the two critical issues of evaluating the necessity of implementing cooling techniques and achieving real-time temperature control of drilling fluids underground in the current drilling fluid cooling technology,we first established a temperature and pressure coupled downhole heat transfer model,which can be used in both water-based and oil-based drilling ***,fourteen factors,which could affect wellbore temperature,were *** on the standard deviation of the downhole temperature corresponding to each influencing factor,the influence of each factor was *** influencing factors that can be used to guide the drilling fluid's cooling technology were drilling fluid thermal conductivity,drilling fluid heat capacity,drilling fluid density,drill strings rotation speed,pump rate,viscosity,ROP,and injection *** nondominated sorting genetic algorithm was used to optimize these six parameters,but the optimization process took 182 *** these eight parameters'influence rules with the nondominated sorting genetic algorithm can reduce the optimization time to 108 ***,the downhole temperature has been demonstrated to increase with the inlet temperature increasing linearly under quasi-steady *** this law and PID,the downhole temperature can be controlled,which can reduce the energy for cooling the surface drilling fluid and can ensure the downhole temperature reaches the set value as soon as possible.

关键词： Drilling Cooling Influencing factors Analysis Optimization Control

Elastohydrodynamic Lubrication Interface Stiffness and Damping Considering Asperity Lateral Contact

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Acta Mechanica Solida Sinica 2024年第1期37卷 109-123页

作者： Zhiqiang Gao yu Zhang xian Wei Yanfang Zhu Lixia peng Weiping Fu Wen Wang School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048China School of Intelligent Manufacturing Panzhihua UniversityPanzhihua 617000China Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Light Chemical TechnologyYibin 644002China School of Mechanical Engineering Anyang Institute of TechnologyAnyang 455099China

Elastohydrodynamic lubrication(EHL)point contact occurs between two rough surfaces at the mesoscopic level,while the interaction of rough surfaces involves contact between asperities at the microscale *** most cases,the contact between asperities within an interface takes the form of lateral contact rather than peak *** devoid of contact asperities are filled with lubricating ***,conventional models often oversimplify lateral contact forms as interactions between asperities and a smooth,rigid *** simplifications fail to accurately represent the true contact conditions and can lead to inaccuracies in the analysis of EHL’s contact *** address this issue,we have developed a novel EHL interface model comprising two rough *** model allows us to explore the influence of asperity height,contact angle,and contact azimuth angle on EHL interface performance.

关键词： EHL interface Asperity lateral contact Contact stiffness Damping

Growth differentiation factor-15 is a prognostic marker in patients with intermediate coronary artery disease

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Journal of Geriatric Cardiology 2020年第4期17卷 210-216页

作者： Wei WANG xian-Tao SONG yun-Dai CHEN Fei yuAN Feng XU Min ZHANG Kai TAN Xing-Sheng YANG xian-peng yu Kong-Yong CUI Shu-Zheng Lyu Department of Cardiology Beijing Anzhen HospitalCapital Medical University and Beijing Institute of HeartLung and Blood Vessel DiseasesBeijingChina Department of Cardiology the First Medical Center of Chinese PLA General HospitalBeijingChina

Background Growth differentiation factor-15(GDF-15)is involved in multiple processes that are associated with coronary artery disease(CAD).However,little is known about the association between GDF-15 and the future ischemic events in patients with intermediate *** study was conducted to investigate whether plasma GDF-15 constituted risk biomarkers for future cardiovascular events in patients with intermediate *** A prospective study was performed based on 541 patients with intermediate CAD(20%–70%).GDF-15 of each patient was determined in a blinded *** primary endpoint was major adverse cardiac event(MACE),which was defined as a composite of all-cause death,nonfatal myocardial infarction,revascularization and readmission due to angina *** After a median follow-up of 64 months,504 patients(93.2%)completed the ***,the combined endpoint of MACE appeared in 134 patients(26.6%)in the overall population:26 patients died,11 patients suffered a nonfatal myocardial infarction,51 patients underwent revascularization,and 46 patients were readmitted for angina *** plasma levels of GDF-15(median:1172.02 vs.965.25 pg/m L,P=0.014)were higher in patients with ischemic events than those without *** adjusting for traditional risk factors,higher GDF-15 levels were significantly associated with higher incidence of the composite endpoint of MACE(HR=1.244,95%CI:1.048–1.478,Quartile 4 *** 1,P=0.013).Conclusions The higher level of GDF-15 was an independent predictor of long-term adverse cardiovascular events in patients with intermediate CAD.

关键词： Growth differentiation factor-15 Intermediate coronary artery disease Prognosis

Long-term outcomes of PCI vs. CABG for ostial/midshafl lesions in unprotected left main coronary artery

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Journal of Geriatric Cardiology 2017年第4期14卷 254-260页

作者： Cheng-Long GUO xian-peng yu Bang-Guo YANG Meng-Meng LI Ji-Qiang HE Quan LI Cheng-Xiong GU Shu-Zheng Lyu Jian-Zeng DONG Department of Cardiology Beijing Anzhen Hospital Capital Medical University Beijing China Department of Cardiac Surgery Beijing Anzhen Hospital Capital Medical University Beijing China

Background There are limited data on long-term （〉 5 years） outcomes of drug-eluting stent （DES） implantation compared with coro- nary artery bypass grafting （CABG） for ostial/rnidshaft left main coronary artery （LMCA） lesions. Methods Of the 259 consecutive pa- tients in Beijing Anzhen Hospital with ostial/midshaff LMCA lesions, 149 were treated with percutaneous coronary intervention （PCI） with DES and 110 were with CABG. The endpoints of the study were death, repeat revascularization, myocardial infarction （MI）, stroke, the composite of cardiac death, and major adverse cardiac and cerebrovascular events （MACCE, the composite of cardiac death, MI, stroke or repeat revascularization）.The duration of follow-up is 7.1 years （interquartile range 5.3 to 8.2 years）. Results There is no significant differ- ence between the PCI and CABG group during the median follow-up of 7.1 years （interquartile range： 5.3-8.2 years） in the occurrence of death （HR： 0.727, 95% CI： 0.335-1.578; P = 0.421）, the composite endpoint of cardiac death, MI or stroke （HR： 0.730, 95% CI： 0.375-1.421; P = 0.354）, MACCE （HR： 1.066, 95% CI： 0.648-1.753; P = 0.801）, MI （HR： 1.112, 95% CI： 0.414-2.987; P = 0.833）, stroke （HR： 1.875, 95% CI： 0.528-6.659; P = 0.331）, and repeat revascularization （HR： 1.590, 95% CI： 0.800-3.161; P = 0.186）. These results remained after multivariable adjusting. Conclusion During a follow-up up to 8.2 years, we found that DES implantation had similar endpoint outcomes compared with CABG.

关键词： Coronary artery bypass graft Drug-eluting stent Percutaneous coronary intervention

A Weighted Flow related to a Trudinger–Moser Functional on Closed Riemann Surface

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2244-2262页

作者： peng Xiu yu School of Mathematics Renmin University of ChinaBeijing 100872P.R.China

In this paper,with(Σ,g)being a closed Riemann surface,we analyze the possible concentration behavior of a heat flow related to the Trudinger–Moser *** obtain a long time existence for the *** along some sequence of times t_(k)→+∞,we can deduce the convergence of the flow in H2(Σ).Furthermore,the limit function is a critical point of the Trudinger–Moser functional under certain constraint.

关键词： Trudinger-Moser inequality global convergence heat flow

An improved high-fidelity adaptive model for integrated inlet-engine-nozzle based on mechanismdata fusion

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Chinese Journal of Aeronautics 2024年第8期37卷 190-207页

作者： Chen WANG Ziyang yu xian DU Ximing SUN School of Control Science and Engineering Dalian University of TechnologyDalian 116024China Key Laboratory of Intelligent Control and Optimization for Industrial Equipment Ministry of EducationDalian University of TechnologyDalian 116024China

Nowadays,there has been an increasing focus on integrated flight propulsion control and the inlet-exhaust design for the aero-propulsion *** component-level models are inadequate due to installed performance deviations and mismatches between the real engine and the model,failing to meet the accuracy requirements of supersonic *** paper establishes a quasi-one-dimensional model for the inlet-exhaust system and conducts experimental ***,a mechanism-data fusion adaptive modeling scheme using an Extreme Learning Machine based on the Salp Swarm Algorithm(SSA-ELM)is *** study reveals the inlet model’s efficacy in reflecting installed performance,flow matching,and mitigating pressure distortion,while the nozzle model accurately predicts flow coefficients and thrust coefficients,and identifies various operational *** model’s output closely aligns with typical experimental *** combining offline optimization and online adaptive correction,the mechanismdata fusion adaptive model substantially reduces output errors during regular flights and varying levels of degradation,and effectively handles gradual degradation within a single flight ***,the mechanism-data fusion adaptive model holistically addresses total pressure errors within the inlet-exhaust system and normal shock location *** approach significantly curbs performance deviations in supersonic *** example,at Ma=2.0,the system error impressively drops from 34.17%to merely 6.54%,while errors for other flight conditions consistently stay below the 2.95%*** findings underscore the clear superiority of the proposed method.

关键词： Aero-propulsion system Integrated inlet-enginenozzle Component-level model On-board adaptive model Mechanism-data fusion Extreme learning machine

Impact of prior cerebrovascular events on patients with unprotected left main coronary artery disease treated with coronary artery bypass grafting or percutaneous coronary intervention

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Chinese Medical Journal 2021年第16期134卷 1988-1990页

作者： yu Pan yu Mu Ze-Sen Liu yu-Chen Zhang Ji-Qiang He xian-peng yu Qi Qiu Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China Department of Pharmacy Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China Department of Cardiology Beijing Luhe HospitalCapital Medical UniversityBeijing 101100China.

Treatment of unprotected left main coronary artery(ULMCA)disease with coronary artery bypass grafting(CABG)or percutaneous coronary intervention(PCI)has developed rapidly during the past *** optimal revascularization strategy has been a subject of debate,with several randomized controlled trials and metaanalyses comparing outcomes of CABG and PCI.

关键词： coronary bypass artery

Effects of cooling rate on microstructure and microhardness of directionally solidified Galvalume alloy

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China Foundry 2024年第3期21卷 213-220页

作者： Ji-peng Li De-gao Qiao Jian Li Xiao-yang Luo peng peng xian-tao Yan Xu-dong Zhang Gansu Jiu Steel Group Hongxing Iron and Steel Co. Ltd.Jiayuguan 735111GansuChina School of Materials and Energy Lanzhou UniversityLanzhou 730000China

The influences of cooling rate on the phase constitution,microstructural length scale,and microhardness of directionally solidified Galvalume(Zn-55Al-1.6Si)alloy were investigated by directional solidification experiments at different withdrawal speeds(5,10,20,50,100,200,and 400μm·s^(-1)).The results show that the microstructure of directionally solidified Galvalume alloys is composed of primary Al dendrites,Si-rich phase and(Zn-Al-Si)ternary eutectics at the withdrawal speed ranging from 5 to 400μm·s^(-1).As the withdrawal speed increases,the segregation of Si element intensifies,resulting in an increase in the area fraction of the Si-rich *** addition,the primary Al dendrites show significant refinement with an increase in the withdrawal *** relationship between the primary dendrite arm spacing(λ_(1))and the thermal parameters of solidification is obtained:λ_(1)=127.3V^(-0.31).Moreover,as the withdrawal speed increases from 5 to 400μm·s^(-1),the microhardness of the alloy increases from 90 HV to 151 *** is a combined effect of grain refinement and second-phase strengthening.

关键词： Galvalume alloy directional solidification microstructure length scale microhardness

Al-containing Ge-rich IWV:rapid synthesis via interzeolite transformation and application in Baeyer-Villiger oxidation

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Science China Chemistry 2024年第7期67卷 2282-2291页

作者： Meichen Jiao Chunmin Jia Hao Xu peng Wu xian-Ming Zhang School of Chemistry&Material Science Shanxi Normal UniversityTaiyuan 030006China Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China School of Chemistry Taiyuan University of TechnologyTaiyuan 030024China

Ge-containing Lewis acidic zeolites are typically synthesized using a conventional hydrothermal strategy from amorphous silica sources,through a long time-and energy-consuming approach limiting their wide *** study reports a rapid synthesis strategy for a series of IWV aluminogermanosilicate zeolites(T-x-Al)with a wide range of Si/Ge molar ratios(5–15)by interzeolite transformation of dealuminated FAU(DA-FAU).Notably,Ge-rich IWV could be obtained with crystallization time as short as one day by the equimolecular Si/Ge ratio *** effect of synthetic parameters was investigated and the obtained T-x-Al samples were characterized by XRD,SEM,EDS,ICP,^(29)Si and^(27)Al MAS NMR,FTIR,and N_(2)physisorption *** with a previously reported IWV germanosilicate(H-3),T-x-Al displayed a better catalytic activity in Baeyer-Villiger(BV)oxidation,attributed to the presence of the active framework Ge sites with the assistance of the extraframework Al *** cyclic catalysis tests revealed that the presence of framework Al species contributed to the stability of the ***,T-x-Al,with 14-membered ring(MR)supercages,outperformed the typical 12-MR Sn-beta catalyst in the BV oxidation of large ketone-like 2-admantanone,indicating a promising potential application in the macromolecular catalytic process.

关键词： Ge-rich IWV interzeolite transformation Al assistance Baeyer-Villiger oxidation