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

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

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Chaotic Dynamics of Monotone Twist Maps

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Acta Mathematica Sinica,English Series 2022年第1期38卷 179-204页

作者： guo wei yu Chern Institute of Mathematics and LPMC Nankai UniversityTianjin 300071P.R.China

For a monotone twist map,under certain non-degenerate condition,we showed the existence of infinitely many homoclinic and heteroclinic orbits between two periodic neighboring minimal orbits with the same rotation number,which indicates chaotic *** results also apply to geodesics of smooth Riemannian metrics on the two-dimension torus.

关键词： Monotone twist maps homoclinic and heteroclinic orbits topological entropy

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Subspace decomposition-based correlation matrix multiplication

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Journal of Systems Engineering and Electronics 2008年第2期19卷 241-245页

作者： Cheng Hao guo wei yu Jingdong National Key Lab of Communication Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

The correlation matrix, which is widely used in eigenvalue decomposition （EVD） or singular value decomposition （SVD）, usually can be denoted by R = E[yiy＇i]. A novel method for constructing the correlation matrix R is proposed. The proposed algorithm can improve the resolving power of the signal eigenvalues and overcomes the shortcomings of the traditional subspace methods, which cannot be applied to low SNR. Then the proposed method is applied to the direct sequence spread spectrum （DSSS） signal＇s signature sequence estimation. The performance of the proposed algorithm is analyzed, and some illustrative simulation results are presented.

关键词： subspace theory correlation matrix eigenvalue decomposition direct sequence spread spectrum signal

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Simultaneous nitrogen and phosphor removal in an aerobic submerged membrane bioreactor

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Journal of Environmental Sciences 2006年第3期18卷 439-445页

作者： WANG Zhi-wei WU Zhi-chao GU guo-wei yu guo-ping MA Lu-ming State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University Shanghai200092 China.

Simultaneous nitrification and denitrification （SND） effect and phosphor removal were investigated in a one-staged aerobic submerged membrane bioreactor on pilot-scale with mixed liquor suspended solids （MLSS） 19--20 g/L. The effects of DO concentration, sludge floc size distribution on SND were studied. Test results suggested that SND was successfully performed in the membrane bioreactor （MBR） and about 70% total nitrogen removal efficiency was achieved when DO concentration was set to 0.2-- 0.3 mg/L. The main mechanisms governing SND were the suitable sludge floc size and the low DO concentration which was caused by low oxygen transfer rate with such a high MLSS concentration in the MBR. In the meantime, phosphor removal was also studied with polymer ferric sulfate （PFS） addition and 14 mg/L dosage of PFS was proper for the MBR to remove phosphor. PFS addition also benefited the MBR operation owing to its reduction of extracellular polymer substances （EPS） of mixed liquor.

关键词： membrane bioreactor (MBR) flat-sheet membrane simultaneous nitrification and denitrifiction (SND) phosphorremoval wastewater treatment oxygen transfer rate

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Balloon catheterization for hemostasis during the operation of ruptured femoral artery pseudoaneurysm

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Chinese Medical Journal 2007年第21期120卷 1943-1944页

作者： SHI De-bing FU wei-guo WANG yu-qi guo Da-qiao CHEN Bin SHI Zhen-yu Department of Vascular Surgery Institute of Vascular Surgery Zhongshan Hospital Fudan University Shanghai 200032 China

Pseudoaneurysms of the femoral artery usually progress and can rupture if left untreated. Therefore,intraoperative hemostasis is of the paramount importance in the management of these emergent situations, especially for the patients with poor general health. We present an efficient method of stopping massive bleeding occurring in this patient by balloon catheter.

关键词： drug abuse aneurysm, false infection balloon catheterization

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Expression of non-structural protein NS3 gene of Bombyx mori densovirus (China isolate)

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Journal of Genetics and Genomics 2008年第4期35卷 239-244页

作者： Huijuan Yin Qin Yao Zhongjian guo Fang Bao wei yu Jun Li Keping Chen Institute of Life Sciences Jiangsu University 301# Xuefu Road Zhenjiang 212013 China

The invertebrate parvovirus Bombyx mori Densonucleosis Virus type 3 （China isolate）, named BmDNV-3, is a kind of bidensovirus. It is a new type of virus with unique replication mechanisms. To investigate the effects of the NS3 gene during viral DNA replication, a pair of primers was designed for amplifying NS3 gene of Bombyx mori densovirus （China isolate）. Gene NS3 amplified was cloned into a prokaryotic expression vector pET-30a and the donor plasmid pFastBacHTe, respectively. The NS3 protein was expressed in Escherichia coli BL21. The pFastBacHTe-NS3 was transformed to E. coli DHIOBac. The recombinant bacmid baculoviruses （rBacmid-EGFP-NS3） isolated from the white colonies were transfected into BmN-4 cells using a transfection reagent. BraN-4 cells were infected with recombinant virus to express fusion proteins. The expression of fusion protein around 30 kDa in E. coli BL21 was identified by SDS-PAGE, Western blotting, and mass spectrometry. The expressed NS3 protein by B. mori nucleopolyhedrovirus bacmid system was confirmed by Western blotting using an anti-NS3 polyclonal antibody. And about 45 kDa protein was found. The expressed fusion protein was smaller than the expected size of EGFP-NS3, 55 kDa. Western blotting analysis indicated that EGFP-NS3 protein was expressed in infected larvae with smaller molecular size.

关键词： BmDNV NS3 protein expression

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Retroperitoneoscopic renal pedical lymphatic disconnection in the treatment of chyluria

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Chinese Medical Journal 2008年第15期121卷 1478-1480页

作者： XIA guo-wei DING Qiang yu Jiang XU Ke ZHANG yuan-fang Department of Urology Huashan Hospital Fudan University Shanghai 200040 China

Chyluria is a disease that may severely debilitate a patient＇s health condition. Some investigations have indicated that in patients with chyluria, part of the uptake fat and protein leaks from the ***, recurrent chyluria may result in malnutrition. In addition, with nearly one half of the body＇s the urine, depressed regulatory lymphocytes lost through functions of the lymphatic system may cause illnesses following immune deficiency. Therefore, it is imperative to provide effective and active medical care for chyluria patients. The purpose of surgical treatment is to eliminate lymphatic fistula and decrease intralymphatic pressure. We recently performed retroperitoneoscopic renal pedical lymphatic disconnection for 78 cases of chyluria patients in our hospital between April 2003 and June 2007. We herein summarize our experience as follows.

关键词： chyluria retroperitoneoscopy renal pedical lymphatic disconnection

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An experimental study on effects of temperature gradient on microstructure of a 308L stainless steel manufactured by directed energy deposition

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Journal of Iron and Steel Research International 2024年第8期31卷 2031-2040页

作者： Ting Dai De-yu Gu yu-wen Qiu wei guo Hui Ding Yi-wei Sun School of Materials Science and Engineering Jiangsu Key Laboratory of Advanced Metallic MaterialsSoutheast UniversityNanjing 211189JiangsuChina

The effect of spatial temperature gradient on the microstructural evolution of a 308L stainless steel during the directed energy deposition(DED)process was experimentally investigated.A novel cooling system was designed and incorporated to a DED system in order to control the temperature gradient along the deposition direction during *** deposition,the workpiece was placed on a lifting platform,and as the deposition process proceeded,the platform and workpiece were gradually lowered into cooling water so that the temperature gradient along the deposition direction could be controlled and maintained stable during the deposition *** microstructure characterization results indicated that a deposition strategy with higher G and G/R values(where G is temperature gradient and R is solidification rate)produced finer cellular grains that were better aligned with the deposition direction,while a deposition strategy with lower G and G/R values produced columnar grains with larger primary arm spacing and less aligned with the deposition direction.

关键词： Additive manufacturing Directed energy deposition Stainless steel Microstructure Temperature gradient

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A Novel Semi-rigid Nephroscope Percutaneous Nephrolithotomy： The Best Therapy for Renal Staghorn Calculi

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Chinese Medical Journal 2015年第22期128卷 3109-3111页

作者： Bo Xiao Song Chen Xin Zhang wei-guo Hu yu-Bao Liu yu-Zhe Tang Jian-Xing Li Department of Urology Beijing Tsinghua Changgung Hospital Medical Center Tsinghua University Beijing 102218 China

Percutaneous nephrolithotomy （PCNL） has been the first-line treatment for renal staghorn calculi for many years. Several techniques have been described for percutaneous access and stone removal, but a multi-access approach is the mainstay of treatment. The main concern about PCNL is the resultant morbidity： Complications such as bleeding, parenchymal damage, and organ injury hindered the adoption of PCNL in primary hospitals in China.

关键词： Kidney Percutaneous Nephrolithotomy Semi-rigid Staghorn

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Application of occluders in endovascular repair of aortic aneurysms

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Chinese Medical Journal 2007年第15期120卷 1366-1368页

作者： SHI Zhen-yu FU wei-guo WANG yu-qi guo Da-qiao CHEN Bin JIANG Jun-hao XU Xin YANG Jue ZHU Ting Institute of Vascular Surgery Zhongshan Hospital Fudan University Shanghai 200032 China

Since Parodi et all reported the first successful case of endovascular treatment for abdominal aortic aneurysm （AAA） in 1991, the endovascular repair has become an important option for the surgical treatment of aortic aneurysms.2-4 The occluder is a newly-developed device introduced intraluminally to block the blood flow in certain arteries. It was mainly adopted by cardiologists in occluding the ventricular septal defect （VSD） and atrial septal defect （ASD）.5-6 Afterwards, vascular surgeons found it could also be used in endovascular repair of aortic aneurysms, especially when the aorto-uni-iliac （AUI） stent-grafts were implanted.7 Herein we present 6 patients with AAA, who were treated with endovascular deployment of AUI stent-grafts combined with a newly- designed occluder.

关键词： aneurysm aorta, abdominal endovascular repair occluder

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