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Synthesis and evaluation of an oil-soluble visco.ity reducer for heavy oil

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Petroleum Science 2010年第4期7卷 536-540页

作者： Guo Jixiang Wang Heyi Chen Chaogang Chen Yun Xie Xiaohai Enhanced Oil Reco.ery Research Center China University of Petroleum Beijing 102249 China Research Institute of Shaanxi Yanchang Petroleum（group） co. ltd Shaanxi 710075 China Northwest Oilfield Branch engineering and Technology Institute of Sinopec Urumchi 830011 China Tuha Oilfield Hami Xinjiang 839009 China Yumen Oilfield Yaerxia Operation Area Gansu 735019 China

To reduce the visco.ity of highly-visco.s oil of the Tahe oilfield （Xinjiang,china）,an oilsoluble polybasic co.olymer visco.ity reducer for heavy oil was synthesized using the orthogonal *** optimum reaction co.ditions are obtained as follows：under the protection of nitrogen,a reaction time of 9 h,monomer mole ratio of reaction materials of 3：2：2 （The monomers are 2-propenoic acid,doco.yl ester,maleic anhydride and styrene,respectively）,initiator amount of 0.8% （mass percent of the sum of all the monomers） and reaction temperature of 80 *** synthesized visco.ity reducer is more effective than co.mercial visco.ity *** rate of visco.ity reduction reached 95.5% at 50 *** spectra （IR） and interfacial tensions of heavy oil with and without visco.ity reducer were investigated to understand the visco.ity reduction *** visco.ity reducer is added,the molecules of the visco.ity reducer are inserted amongst the molecules of crude oil,altering the original intermolecular structure of crude oil and weakening its ability to form hydrogen bonds with hydroxyl or carboxyl groups,so the visco.ity of crude oil is *** tests of the newly developed oil-soluble visco.ity reducer was carried out in the Tahe Oilfield,and the results showed that 44.5% less light oil was needed to dilute the heavy oil to achieve the needed visco.ity.

关键词： Oil-soluble visco.ity reducer heavy oil synthesis evaluation

Hybrid method of limit equilibrium and finite element internal force for analysis of arch dam stability against sliding

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Science china(Technological Sciences) 2011年第4期54卷 793-798页

作者： BAO TengFei1,2,3,XU BaoSong1,2,3 & ZHENG XueQing1,2,3 1State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering,Hohai University,Nanjing 210098,china 2National engineering Research Center of Water Resources Efficient Utilization and engineering Safety,Nanjing 210098,china 3co.lege of Water co.servancy and Hydropower engineering,Hohai University,Nanjing 210098,china State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering Hohai University Nanjing China National engineering Research Center of Water Resources Efficient Utilization and engineering Safety Nanjing China co.lege of Water co.servancy and Hydropower engineering Hohai University Nanjing China

A hybrid method of limit equilibrium and finite element internal force for analysis of arch dam stability against sliding is *** finite element internal force method(FEIFM) is used to provide more accurate thrust forces acting on the faces of a slip body,and the limit equilibrium method(LEM) is employed to evaluate the factor of safety of the slip *** method presented can deal with a slip body with large amount of geometrically co.plex slip *** addition,co.pared with the traditional LEM,it can meet the balance co.dition of the forces in the slip *** example shows that the factor of safety obtained by the method presented agrees well with the theoretical solution.A practical example is also presented to demonstrate the application of the method in the stability analysis of an arch dam *** results from the examples show that the method is promising in analysis of arch dam stability against sliding.

关键词： arch dam stability against sliding limit equilibrium method finite element internal force method

Photoluminescence and cathodoluminescence properties of a novel CaLaGa_3O_7:Dy^(3+) phosphor

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Chinese Science Bulletin 2012年第7期57卷 827-831页

作者： ZHAO WenYu1,2, AN ShengLi1, FAN Bin1, LI SongBo1 & DAI YaTang3 1 School of Metallurgical and Eco.ogical engineering, University of Science and Technology beijing, beijing 100083, china 2 School of Chemistry and Chemical engineering, Inner Mongolia University of Science and Technology, Baotou 014010, china 3 School of Materials Science and engineering, Southwest University of Science and Technology, Mianyang 621000, china School of Metallurgical and Eco.ogical engineering University of Science and Technology Beijing Beijing China School of Chemistry and Chemical engineering Inner Mongolia University of Science and Technology Baotou China School of Materials Science and engineering Southwest University of Science and Technology Mianyang China

A single host white emitting phosphor, CaLaGa3O7:Dy3+, was synthesized by chemical co.precipitation. Field emission scanning electron microsco.y, X-ray diffraction, laser particle size analysis, and photoluminescence and cathodoluminescence spectra were used to investigate the structural and optical properties of the phosphor. The phosphor particles were co.posed of microspheres with a slight tendency to agglomerate, and an average diameter was of about 1.0 μm. The Dy3+ ions acted as luminescent centers, and substituted La3+ ions in the single crystal lattice of CaLaGa3O7 where they were located in Cs sites. Under excitation with ultraviolet light and a low voltage electron beam, the CaLaGa3O7:Dy3+ phosphor exhibited the characteristic emission of Dy3+ (4F9/2-6H15/2 and 4F9/2-6H13/2 transitions) with intense yellow emission at about 573 nm. The chromaticity co.rdinates for the phosphor were in the white region. The relevant luminescence mechanisms of the phosphor are investigated. This phosphor may be applied in both field emission displays and white light-emitting diodes.

关键词：光致发光阴极射线荧光粉镝离子场发射扫描电子显微镜白色发光二极管特性 X射线衍射仪

Autonomous Landing of Small Unmanned Aerial Rotorcraft Based on Monocular Vision in GPS-denied Area

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IEEE/CAA Journal of Automatica Sinica 2015年第1期2卷 109-114页

作者： Cunxiao Miao Jingjing Li the School of Mechanical engineering University of Science and Technology Beijing beijing Aerospace Times Optical-electronic Technology co. Ltd(ATOT)

Focusing on the low-precision attitude of a current small unmanned aerial rotorcraft at the landing stage, the present paper proposes a new attitude co.trol method for the GPS-denied scenario based on the monocular vision. Primarily, a robust landmark detection technique is developed which leverages the well-documented merits of supporting vector machines (SVMs) to enable landmark detection. Then an algorithm of nonlinear optimization based on Newton iteration method for the attitude and position of camera is put forward to reduce the projection error and get an optimized solution. By introducing the wavelet analysis into the adaptive Kalman filter, the high frequency noise of vision is filtered out successfully. At last, automatic landing tests are performed to verify the method's feasibility and effectiveness. © 2014 Chinese Association of Automation.

关键词： Aircraft Attitude co.trol Helico.ter rotors Landing Nonlinear programming Rotors Vision Wavelet analysis

Structural studies of dicycloplatin,an antitumor supramolecule

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Science china Chemistry 2010年第6期53卷 1346-1351页

作者： YANG XuQing1,2,JIN XiangLin2,SONG QinHua1,TANG KaLuo2,YANG ZhenYun1,ZHANG XiaoFeng1 & TANG YouQi2 1beijing Suo Pu Xing Da Pharmaceutical co.ltd.,beijing 100081,china 2co.lege of Chemistry and Molecular engineering,Peking University,beijing 100871,china beijing Suo Pu Xing Da Pharmaceutical co. ltd. Beijing China co.lege of Chemistry and Molecular engineering Peking University Beijing China

The solubility and stability of platinum-based anticancer agents have a direct bearing on their activity and *** research has been co.ducted over the past decades in order to prepare drugs such as cisplatin and carboplatin with improved efficacy and reduced *** on the premise that supramolecular platinum agents may have superior physico.hemical properties,we successfully designed a novel anticancer agent,dicycloplatin,which has proven to be active against a number of human *** crystal structure of dicycloplatin has been *** aqueous solution of dicycloplatin was also studied using electrospray ionization mass spectrometry (ESI-MS).Based on the experimental observations,a model of the structure in aqueous solution is proposed which explains both the higher solubility and higher stability of dicycloplatin co.pared with carboplatin.

关键词： dicycloplatin crystal structure supramolecule anticancer

Tension and Thickness co.trol Strategy Analysis of Two Stands Reversible co.d Rolling Mill

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Journal of Iron and Steel Research International 2012年第10期19卷 20-25页

作者： LIU Guang-ming1, DI Hong-shuang2, ZHOU Cun-long1, LI Hong-cui3, LIU Jiang3 (1. co.lege of Materials Science and engineering, Taiyuan University of Science and Technology, Taiyuan 030024, Shanxi, china 2. State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819, Liaoning, china 3. co.d Rolling Plant, Jinan Iron and Steel Group co.ltd, Jinan 250101, Shandong, china) co.lege of Materials Science and engineering Taiyuan University of Science and Technology Taiyuan Shanxi China State Key Laboratory of Rolling and Automation Northeastern University Shenyang Liaoning China co.d Rolling Plant Jinan Iron and Steel Group Co Ltd Jinan Shandong China

In order to lucubrate the rolling characteristic of the two stands reversible co.d rolling mill and establish the tension and thickness co.trol strategy, the steady-state characteristic simulating program was established using the steady-state co.tinuous rolling theory. The influences of each factor on exit thickness under different tension co.trol methods were analyzed. The results show that, the influence of the entry stand gap on exit thickness is significant and it changes little with different tension co.trol methods. As a result, the entry stand gap can be used as the main co.trol method of exit thickness, whereas rolling speed of any stand and roll gap of the exit stand can be used to adjust the inter-stand tension. The results are beneficial for thickness and tension co.trol of the two stands reversible co.d rolling mill.

关键词： two stand reversible co.d rolling thickness tension co.trol strategy

Flatness and Profile Integration co.trol Model for Tandem co.d Mills

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Journal of Iron and Steel Research International 2012年第3期19卷 31-37页

作者： SHAN Xiu-ying1,2,3, LIU Hong-min1,2, JIA Chun-yu1,2, SUN Jian-liang1,2 (1. engineering Research Center of Rolling Equipment and co.plete Technology of Ministry of Education, Yanshan University, Qinhuangdao 066004, Hebei, china 2. State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, Hebei, china 3. Hot Tandem Rolling Factory, Jinan Iron and Steel co.ltd, Jinan 250101, Shandong, china) engineering Research Center of Rolling Equipment and co.plete Technology of Ministry of Education Yanshan University Qinhuangdao Hebei China State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao Hebei China Hot Tandem Rolling Factory Jinan Iron and Steel Co Ltd Jinan Shandong China

Using the effective matrix methods of flatness and profile co.trol synthetically, the flatness and profile in- tegration co.trol scheme for tandem co.d mills is built in order to increase flatness and profile co.trol precision of tan- dem co.d mills. co.responding co.trol strategies are adopted for various co.trol objectives of different stands and the co.rdination co.trol strategies of various stands are given, which makes the on-line flatness co.trol co.perate with on-line profile co.trol and implements the parallel co.trol of different stands. Acco.ding to the measured flatness and profile data of some 1550 mm tandem co.d mills, the co.trol scheme is verified and the result indicates that the scheme has high flatness and profile co.trol precision with steady and reliable co.trol process. A new way and method is supplied for researching shade co.trol of tandem co.d mills.

关键词： flatness profile shape effective matrix tandem co.d mill

Tempo-spatial characteristics and influential factors of rockburst:a case study of transportation and drainage tunnels in Jinping Ⅱ hydropower station

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Journal of Rock Mechanics and Geotechnical engineering 2011年第2期3卷 179-185页

作者： Lipeng Liu1, 2, Xiaogang Wang1, Yizhong Zhang3, Zhixin Jia1, Qingwei Duan1 1 Department of Geotechnical engineering, china Institute of Water Resources and Hydropower Research, beijing, 100048, china 2 School of engineering and Technology, china University of Geosciences, beijing, 100083, china 3 beijing Vibroflotation engineering co., ltd., beijing, 100102, china Department of Geotechnical engineering China Institute of Water Resources and Hydropower Research Beijing 100048 China School of engineering and Technology China University of Geosciences Beijing 100083 China beijing Vibroflotation engineering co. Ltd. Beijing 100102 China

Jinping Ⅱ hydropower station is located in a high in-situ stress region in Southwest china. During the excavations of the transportation and drainage tunnels, more than 460 rockburst events were reco.ded in the transportation tunnel and 110 in the drainage tunnel, which has a serious and negative influence on the tunnels’ co.struction and the safety of staff and equipment. In the paper, the characters of rockburst patterns are analyzed for the transportation and drainage tunnels. The results are illustrated as follow: (1) Most of intensive rockbursts occur in the layer T2b, and co.tinuous occurrences of rockbursts are more frequently observed than those in other layers. (2) The critical overburden depth of rockburst in the transportation tunnel is 600 m, and the length of the co.tinuous occurrence section of rockburst is smaller than 25 m. The damaged depth of the rockburst has the tendency to increase with the increasing overburden depth, and the maximum damaged depth is over 3.5 m. (3) From east to west (west to east) in Jinping Ⅱ hydropower station, the rockburst usually takes place in the right (left) side of tunnel working face, and then the left (right) or roof of the tunnel. The total length of the co.tinuous occurrence section of rockburst is 57.4%–62.2% of the overall rockburst length, followed by the rockbursts of flake-splitting type and other types. (4) co.pared with the transportation tunnel, the intensity of rockburst in the drainage tunnel is higher while the length of the co.tinuous occurrence section of rockburst is smaller. The rockburst section with length less than 10 m and depth of 1 m mainly occurs in the layer at a depth of 1 800–2 000 m. The influences of opening geometry and excavation method on the characteristics of the adjacent zone are great, but the influence of the stress among the tunnel group induced by excavation is relatively low.

关键词： Jinping Ⅱ hydropower station rockburst developing pattern influential factor

Topology Based Reliable Virtual Network Embedding from a QoE Perspective

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china co.munications 2018年第10期15卷 38-50页

作者： Peiying Zhang Sheng Wu Miao Wang Haipeng Yao Yunjie Liu co.lege of co.puter & co.munication engineering China University of Petroleum (East China) State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications DFH Satellite co. Ltd.

In the network virtualization environments, one of the most challenges is how to map the virtual networks(VNs) onto a shared substrate network managed by an infrastructure provider(In P), which is termed as virtual network embedding problem. Prior studies on this issue only emphasize on maximizing the revenue or minimizing the energy co.sumption while ignoring the reliability requirements of end-users. In our work, we inco.porate the reliability probability into the virtual network embedding process with an aim to improve the Qo S/Qo E of end users from a new perspective. We devised two novel reliable virtual network embedding algorithms called RRW-Max Match and RDCC-VNE based on RW-Max Match and DCC-VNE, respectively. Extensive simulations demonstrated that the efficiency of our proposed algorithms is better than those of two primitive algorithms in terms of the reliability demands, the acceptance ratio of virtual networks and the long-term average revenue.

关键词： virtual network embedding reliability probability node mapping procedure link mapping procedure node ranking metric