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Modification of waste polyacrylonitrile fiber and its application as a filtrate reducer for drilling

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Petroleum Science 2015年第2期12卷 325-329页

作者： pei-Zhi yu School of Engineering and Technology China University of Geosciences(Beijing)

Cationic polymer fluid loss additive （CPFL） was prepared by using the reaction of 2,3-epoxypropy- ltrimethyl ammonium chloride （EPTMAC）（as cationic reagent） with the amide group in the molecular structure of the sodium salt of partially hydrolyzed polyacrylonitrile fibers （HPAN-Na）. The chemical reaction was determined by studying the infrared absorption peaks of the materials and the products. The results proved that the cationic groups of EPTMAC were successfully grafted onto the HPAN molecular chain. The composition of the molecular chain of the product CPFL was determined by investigation and calculation of the elemental analysis results of the grafted HPAN and the final reaction product CPFL. The drilling fluid performance was evaluated, and the result showed that when the cation content was more than 0.27 mmol/g, the drilling fluid would have good resistance to fluid loss and to pollution from calcium chloride.

关键词： Acrylic fiber Cationic agents Fluid lossagent. Spectroscopy

FAULT CAUSED BY WATER PRESSURE IN THE HEAD-COVER CHAMBER

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Journal of Hydrodynamics 2006年第3期18卷 280-286页

作者： pei Hai-lin QI Xue-yi LI Hui LI Jian-hui pei Ze-yu College of Fluid Power and Control Lanzhou University of Technology Lanzhou 730050 China Gansu Electrical and scientifical Institute Lanzhou 730050 China Vernon Barford School Edmonton Alberta T6J2X6 Canada

Owing to the high temperature of the thrust beating pads, the No.l unit wasn＇t performed in the upgrading test at Liujiaxia Hydropower Plant. Through the experimental and theoretical analysis, it has been confirmed that the fault unit was caused by the high water pressure in the head-cover chamber. This type of the fault is out-of-the-way. After the suitable measure wags against the fault were taken, the No. 1 unit can stably operate. The conclusions and the methodology are of the certain reference value to the fault-diagnosis of the hydroelectric unit.

关键词： hydroelectric unit perturbation vibration,fault diagnosis

A new kind of nonlinear fractional-order chaotic phenomenon in coupled systems： coexistence of anti-phase and complete synchronization

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Chinese Physics B 2011年第8期20卷 90-96页

作者： Zhang Jun-Feng pei Qiu-yu Zhang Xiao-Li Department of Computer Science and Engineering Henan University of Urban Construction Pingdingshan 467036 China The Aeronautical Science Key Laboratory for Smart Material and Structures Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

In this paper, we have found a kind of interesting nonlinear phenomenon hybrid synchronization in linearly coupled fractional-order chaotic systems. This new synchronization mechanism, i.e., part of state variables are anti- phase synchronized and part completely synchronized, can be achieved using a single linear controller with only one drive variable. Based on the stability theory of the fractional-order system, we investigated the possible existence of this new synchronization mechanism. Moreover, a helpful theorem, serving as a determinant for the gain of the controller, is also presented. Solutions of coupled systems are obtained numerically by an improved Adams Bashforth-Moulton algorithm. To support our theoretical analysis, simulation results are given.

关键词： fractional-order unified chaotic system hybrid synchronization linear controller singledrive variable

Global Weak Solutions to a Fluid-particle System of an Incompressible Non-Newtonian Fluid and the Vlasov Equation

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Acta Mathematicae Applicatae Sinica 2024年第4期40卷 954-978页

作者： pei-yu ZHANG Li FANG Zhen-hua GUO Department of Mathematics Northwest UniversityXi’an 710127China School of Mathematics and Information Science&Center for Applied Mathematics of Guangxi Guangxi UniversityNanning 530004China

The purpose of this work is to investigate the existence and uniqueness of weak solutions to the initial-boundary value problem for a coupled system of an incompressible non-Newtonian fluid and the Vlasov *** coupling arises from the acceleration in the Vlasov equation and the drag force in the incompressible viscous non-Newtonian fluid with the stress tensor of a power-law structure for p≥11/*** main idea of the existence analysis is to reformulate the coupled system by means of a so-called truncation *** advantage of the new formulation is to control the external force term G=-∫Rd(u-v)fdc(d=2,3).The global existence of weak solutions to the reformulated system is shown by using the Faedo-Galerkin method and weak compactness *** further prove the uniqueness of weak solutions to the considered system.

关键词： incompressible non-Newtonian fluid Vlasov equation global weak solutions

Perception of Nonlinear Distortion in Music Signals Reproduced by Microspeakers

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Sound & Vibration 2018年第5期52卷 6-11页

作者： pei yu Yong Shen Ziyun Liu Institute of Acoustics Key Laboratory of Modern Acoustics of Ministry of EducationNanjing UniversityNanjing210093China

A lot of work has focused on compensating nonlinear distortions ofthe microspeaker under large excitation, yet it is unclear at which levelthe effect of nonlinear distortion is imperceptible or not annoying. Inthis study virtual listening tests were performed to evaluate thedeterioration of sound quality in music signals with different levels ofnonlinear distortion by a microspeaker. Binaural recordings of themusic played by the microspeaker were made at different voltagelevels, adjusted to the same RMS power, and afterwards reproducedby a low distortion reference headphone. The “double-blind triple-stimuluswith hidden reference” method was used in the listening tests. Listenerswere required to not only discern the distortion, but also rank theseverity of the distortion. The effects of several factors includingsubject, program material and distortion level on the perceiveddistortion are discussed.

关键词： Nonlinear distortion microspeaker virtual listening test

Small-amplitude limit cycles of polynomial Linard systems

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Science China Mathematics 2013年第8期56卷 1543-1556页

作者： HAN MaoAn TIAN yun yu pei Department of Mathematics Shanghai Normal University Department of Applied Mathematics The University of Western Ontario

In this paper, we study the number of limit cycles appeared in Hopf bifurcations of a Lienard system with multiple parameters. As an application to some polynomial Lienard systems of the form x= y, y= -gin（x） - fn（X）y, we obtain a new lower bound of maximal number of limit cycles which appear in Hopf bifurcation for arbitrary degrees m and n.

关键词： limit cycle Lienard system Hopf bifurcation

Anesthetic management for intraoperative acute pulmonary embolism during inferior vena cava tumor thrombus surgery:A case report

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World Journal of Clinical Cases 2022年第15期10卷 5111-5118页

作者： pei-yu Hsu En-Bo Wu Department of Anesthesiology China Medical University HospitalChina Medical UniversityTaichung 404Taiwan Department of Anesthesiology Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of MedicineKaohsiung 833Taiwan

BACKGROUND Acute pulmonary embolism(APE)is a rare and potentially life-threatening condition,even with early detection and prompt *** APE required specific ways for detecting since classic symptoms of APE in the awake patient could not be observed or self-reported by the patient under general *** SUMMARY A 44-year-old man with a history of hepatic cell carcinoma was admitted for radical nephrectomy and tumor thrombectomy due to a newly found kidney tumor with inferior vena cava(IVC)tumor *** that occurred during tumor thrombectomy with hypercapnia and *** capnography combined with the transesophageal echocardiography(TEE)provided a crucial differential diagnosis during the *** patient was continuously managed with aggressive intravenous fluid resuscitation and blood transfusion under continuous cardiac output monitoring to maintain hemodynamic *** completed the surgery under stable hemodynamics and was extubated after percutaneous mechanical thrombectomy by a certified *** were no significant symptoms and signs or obvious discomfort in the patient’s self-report during visits to the general *** Under general anesthesia for IVC tumor thrombus surgery,a sudden decrease in end-tidal carbon dioxide is the initial indicator of APE,which occurs before hemodynamic *** intraoperative APE is suspected,TEE is useful in the diagnosis and monitoring before computer tomography pulmonary *** clinical impression and supportive treatment and intervention should be conducted to obtain a better prognosis.

关键词： Acute pulmonary embolism Anesthesia End-tidal carbon dioxide Inferior vena cava tumor thrombus Transesophageal echocardiography Case report

Slow magnetic relaxation and photoluminescence behaviors of dilanthanide complexes bearing N_(8)O_(2)donor macrocyclic ligand

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Journal of Rare Earths 2024年第7期42卷 1298-1303,I0004页

作者： pei-yu Liao yu-Quan Qi Zhen Li Jian-Hua Jia Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou510006China

On account of the complicated magnetic exchange interactions between lanthanide ions,binuclear lanthanide complexes have broad application prospect in the field of single-molecule ***,it is necessary to develop reasonable bridging ligands to manipulate the directional assembly of binuclear lanthanide ***,we selected the macrocyclic ligand L^(N_(8)O_(2))to build up two new dilanthanide complexes[Ln_(2)(LN_(8)O_(2))(OpyO)_(2)(H_(2)O)2](NO_(3))_(2)(1-Ln,Ln=Dy,Tb;LN_(8)O_(2)=hexamethyl-tetraaza-dioxe-dipyrazolacycloicosaphane-2,9,12,19-tetraene;OpyOH=2-pyridinol-1-oxide).Dynamic magnetic studies show that 1-Dy exhibits slow relaxation behavior under a 1 kOe applied *** fitting analysis of relaxation times gives the effective energy barrier of 38.2 cm^(−1),and reveals that the slow magnetic relaxation behavior is dominated by the Orbach and Raman ***-resolution luminescence emission spectrum indicates the energy gap of 36.8 cm^(−1)between the ground state and the first excited state,consistent with the magnetic measurement results.1-Tb exhibits brilliant characteristic green light emission under UV light *** absolute quantum yield of 1-Tb is 44.8%,and its first-order fitted decay lifetime is 779.21μs at room *** study provides the way for directional construction of high-performance molecular materials with magnetic and optical dual-function.

关键词： Dilanthanide complexes Single-molecule magnets Macrocyclic ligand Photoluminescence behavior Rare earths

The assembly of a composite based on nano-sheet graphene oxide and montmorillonite

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Petroleum Science 2018年第2期15卷 366-374页

作者： yu-Xiu An Wei-Jia Qu pei-Zhi yu Jian-Guo Lu School of Engineering and Technology China University of Geosciences(Beijing)Beijing 100083China

Graphene oxide （GO） nano-sheets were synthesized using a modified Hummers＇ method from graphite powder. The Raman spectrum of GO displayed a D-band at 1359 cm-1 and a G-band at 1594 cm-l. The ID/IG value of GO was calculated to be 0.97, suggesting the formation of new sp2 clusters upon reduction. A method was designed to investigate the assembly of the GO/montmorillonite （MMT） composite. After the addition of GO, the typical peaks of montmorillonite in FT-IR spectra shifted, indicating the assembly between GO and MMT. The D-band and G-band reduced sharply in the GO/MMT composite. More importantly, the D-band （1344 cm-1） and G-band （1574 cm 1） shifted significantly and the ID/ IG value of the GO/MMT composite was calculated to be 1.13, showing a change in the GO structure. In the addition of 0.04 wt% GO to MMT, the value of interlayer space （d） was up to 13.0 Ameasured by XRD due to the insertion of GO into MMT. The evident increases in contents of carbon atoms （26.59%） and nitrogen atoms （3.44%） indicate that GO was successfully combined with MMT. The nano-pores and clay sheets were not observed in the SEM image of GO/clay, but obvious wrinkles, while flexible sheets were observed in the typical scanning electron microscopy images of GO. This further proves that GO was combining with clay. The TEM image shows that the GO nano-sheets were tiled on the surface of MMT sheets. This observation suggests that a stable assembly structure was formed between GO sheets and MMT sheets. The change in particle size of MMT with the addition of GO shows that interaction occurred between GO sheets and MMT sheets, which was further confirmed by the results of zeta potential. Adsorption and insertion were the main mechanisms to assemble GO and MMT.

关键词： Drilling fluid Graphene oxide Montmorillonite Wellbore stability