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3D trajectory inversion of an adjacent well using scattered P-wave

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Petroleum Science 2023年第2期20卷 857-865页

作者： Lu Cheng xiao-Hua Che Wen-xiao qiao Teng Zhao State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China Key Laboratory of Earth Prospecting and Information Technology Beijing102249China

In oil and gas exploitation,cluster well technology can significantly reduce costs and improve *** effective adjacent well detection method can greatly reduce the risk of collision between adjacent *** study proposes a method to invert the 3D trajectory of an adjacent well using a scattered P-wave obtained by borehole azimuthal acoustic reflection *** obtaining the scattered P-wave from the raw data of the target well using the wave field separation technology,the waveform data in an imaging profile can be obtained by the downhole acoustic directional reception *** imaging technology is then used to obtain the image of the formation in the imaging ***,by analyzing the images of the formation in the imaging profile of the different azimuths,the well spacing and azimuth of the target well can be ***,the 3D trajectory of the target well can be obtained by solving the inversion *** method was validated by processing the field data from a deviated well in a deep *** comparison of the inversion and actual trajectories of the target well demonstrated that the maximum deviation of the inversion trajectory is 0.9 m in the north-south direction,0.78 m in the east-west direction,1.45 m in the well spacing,and 2.48°in the *** field data inversion result demonstrated that the method can effectively use the azimuth reflection acoustic data to invert the 3D trajectory of an adjacent well,which indicates that the borehole azimuthal acoustic reflection imaging technology has great potential within the context of adjacent well detection.

关键词： Acoustic imaging Acoustic reflection logging Directional reception Adjacent well

First synthesis of (±)-cedarmycin B

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Chinese Chemical Letters 2009年第9期20卷 1023-1024页

作者： Hai Shen Yang xiao xiao qiao Qing Cui xiao Hua Xu State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

The synthesis of racemic cedannycin B, an antibiotic from Streptomyces sp. TP-A0456 was achieved firstly from γ- butyrolactone. The key step was a Barbier-type addition of 3-bromomethyl-5H-furan-2-one to formaldehyde mediated by zinc, which afforded the sole γ-addition product 4-hydroxymethyl-3-methylene-dihydrofuran-2-one. The final compound was confirmed by 1H NMR, 13C NMR and HRMS. 2009 xiao Hua Xu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Cedarrnycin B Antibiotic Streptomyces sp. Barbier reaction 3-Bromomethyl-5H-furan-2-one

Construction,Expression and Purification of SUMO1-GST Fusion Protein

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Chemical Research in Chinese Universities 2011年第2期27卷 245-248页

作者： qiao xiao-fang FANG Xue-dong LIU Jun The Second Hospital of Jilin University Changchun 130041 P. R.China

Sumoylation is an important protein modification discovered recently. SUMO（small ubiquitin-related modifier） pathway regulates the protein stability and transcriptional activity with a 12-kDa small molecular protein, SUMO, ligated to the target protein. The purification of SUMO proteins is a key step to reveal their function. The purpose of this study was to construct the recombinant SUMO1 gene cloned to a pGEX-4T-1 vector to express and purify the SUMO1-GST fusion protein in Escherichia coli. First, the full length DNA sequence of SUMO1 gene was amplified by PCR and was ligated to pMD18-T vector. Then the SUMO1 gene was subcloned to pGEX-4T-1 prokaryotic expression vector between BamHI and XhoI sites, and transformed in Escherichia coli DH5α cells. The right colonies were identified by restrictive enzyme digestion and sequencing. The correct rebombinant plasmid of pGEX-4T-1-SUMO1 was transformed in Escherichia coli BL21 cells and then induced by IPTG（isopropyl- β-D-1- thiogalacto-pyranoside） to express the SUMO1-GST fusion protein. The highly purified SUMO1-GST（glutathione S-transferase） fusion protein was obtained by affinity chromatography. Finally, the properties of SUMO1-GST fusion protein were confirmed by Coomassie brilliant blue strain and Western blot analysis. The recombinant plasmid of pGEX-4T-1-SUMO1 was successfully constructed, and SUMO1-GST fusion proteins were successfully expressed.

关键词： Small ubiquitin-related modifier 1 (SUMO1) Gutathione S-transferase(GST) fusion protein Affinity chromatography

Preparation and Microstructure of Highly-Oriented LaNiO_3 Thin Films by RF Sputtering Method

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Chinese Journal of Aeronautics 2006年第B12期19卷 142-145页

作者： CHENG Xing-hua qiao Liang BI xiao-fang School of Materials Science and Engineering BeO＇ing University of Aeronautics and Astronautics Beijing 100083 China

In an attempt of being used as buffer layers and electrodes for the textured BaTiO3 （BTO） ferroelectric thin films, highly （100）-oriented LaNiO3 （LNO） thin films of different thicknesses were deposited directly on Si （100） substrate with radio-frequency （RF） magnetron sputtering method. It is observed that the substrate temperatures and the film thicknesses bring main influences on the microstructures and orientation of the thin film. The effects of the thicknesses and substrate temperatures on the orientation of the films were studied on the LNO films of different thicknesses. The highly （100）-oriented LNO thin films were obtained at the substrate temperature of 600℃. The existence of epitaxially grown BTO films indicates that the oriented LNO thin films obtained in this work could be used as a buffer layer for epitaxial growth.

关键词： LaNiO3 film perovskite orientation risistivity

A New Mesopsychid (Mecoptera) from the Middle Jurassic of Northeastern China

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Acta Geologica Sinica(English Edition) 2013年第5期87卷 1235-1241页

作者： SHIH ChungKun qiao xiao Conrad C.LABANDEIRA REN Dong College of Life Sciences Capital Normal University Department of Paleobiology Smithsonian Institution National Museum of Natural History Department of Entomology University of Maryland College Park Department of Geology Rhodes University

The family Mesopsychidae Tillyard, 1917 presently consists of ten described genera from the Early Permian to the Early Cretaceous of Australia, China, Kyrgyzstan, Russia, South Africa, Tajikistan, and Ukraine. Herein, a new genus and a new species of fossil mesopsyehid, Epicharmesopsyche pentavenulosa gen. et sp. nov., is described from the Middle Jurassic Jiulongshan Formation of Inner Mongolia, China, supplementing the family-level diversity. The well-preserved, new material reveals many characters, including antennae, wing venation, shape and genitalia that increase our morphological understanding of the family, although unfortunately the mouthparts and most of the legs are not preserved. Diagnosis of the Mesopsychidae is emended to include a four- or five-branched MP in both the fore- and hind wings. This is the first documentation of a wing coupling structure in the Mesopsychidae, consisting of three to four frenula bristles on the humeral lobe at the base of the costal margin of both hind wings. Asymmetrical shape and size of the left and right wings on a specimen of E. pentavenulosa gen. et sp. nov., seems to be a common condition for mesopsychid taxa from northeastern China.

关键词： new genus and species wing coupling asymmetric wings taxonomic diversity Inner Mongolia

Experimental study of the azimuthal performance of 3D acoustic transmitter stations

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Petroleum Science 2016年第1期13卷 52-63页

作者： xiao-Hua Che Wen-xiao qiao xiao-Dong Ju Jun-Qiang Lu Jin-Ping Wu Ming Cai State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Key Laboratory of Earth Prospecting and Information Technology China University of Petroleum

Better well logging techniques for geologic investigations are urgently needed to identify and evaluate complex *** describe a new type of 3D transmitter station with corresponding circuits and *** can be used in a promising new technique of acoustic reflection well logging,that features better azimuthal detection capabilities,as well as better investigation *** transmitter stations consist of three-level subarrays that can radiate acoustic energy in any required azimuth of 3D space by circularly exciting various combinations at different *** tested the 3D acoustic transmitter stations and obtained laboratory directivity measurements with the3 D acoustic transmitter stations for the first *** results show that the 3-d B beam width in the horizontal plane ranges from 59° to 67° as a result of phase-delayed *** main beam is steered in the vertical plane at a deflection angle that ranges from 0° to 16° when the delay time of the excitation pulse between each pair of adjacent arc arrays is gradually *** 3-d B beam width is equal to 11°,whereas the deflection angle in the vertical plane is equal to 14°.Each of the four third-level subarrays in the same circumferential direction display consistent horizontal and vertical directivities,thus satisfying the requirements of azimuthal acoustic reflection logging.

关键词： transmitter deflection logging urgently geologic satisfying azimuth exciting excitation formations

Antibacterial ability and biocompatibility of fluorinated titanium by plasma-based surface modification

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Rare Metals 2022年第2期41卷 689-699页

作者： Mian Chen xiao-qiao Wang Er-Lin Zhang Yi-Zao Wan Jian Hu Jiangxi Key Laboratory of Nanobiomaterials Institute of Advanced MaterialsEast China Jiaotong UniversityNanchang 330013China Key Laboratory for Anisotropy and Texture of Materials(ATM) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China

Biomaterial surfaces with satisfied antibacterial activity and appropriate cytocompatibility are a pressing clinical need for orthopedic and dental *** biomaterials have been demonstrated to obtain antibacterial activity and osteogenic property,while the effect of fluorine chemical compositions on antibacterial property and cytocompatibility is rarely *** this end,the coatings with different fluorine chemical compositions on titanium surface were prepared by plasma treatment to verify the antibacterial ability and cytocompatibility of fluorinated *** antibacterial ability was evaluated by using Staphylococcus aureus,and the cell compatibility was investigated with MC3T3-E1 cells in *** results show that both fluorocarbon coating and metal fluorides coating exhibited a hydrophilic and nano-scaled *** than the fluorocarbon coating,the coating composed of metal fluorides presented satisfied bactericide effect and excellent *** antibacterial mechanism is associated with the metal fluorides and released fluoride *** work would provide novel sight in optimizing the surface modification method of fluorinated biomaterials for biomedical applications.

关键词： Titanium Plasma-based technology Fluorine Antibacterial property Cytocompatibility

Field validation of imaging an adjacent borehole using scattered P-waves

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Petroleum Science 2020年第5期17卷 1272-1280页

作者： Jian-Lin Ben Wen-xiao qiao xiao-Hua Che xiao-Dong Ju Jun-Qiang Lu Bai-Yong Men State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China Key Laboratory of Earth Prospecting and Information Technology Beijing 102249China

Acoustic waves enter a rock formation from a borehole and are reflected or scattered upon encountering a geologic ***,we obtain the structure location represented by the azimuth and distance from the borehole using the acoustic reflection or *** acoustic measurements with the azimuthal resolution are realized using an azimuthal acoustic receiver sonde composed of several arcuate phased array *** sensors distributed evenly across the arcuate phased array receiver can record acoustic waves independently;this allows us to adopt the beamforming *** use a supporting logging tool to conduct the downhole test in two adjacent fluid-filled boreholes,for validating the evaluation of the geologic structure using scattered *** test results show the multi-azimuth images of the target borehole and the azimuthal variation in scattering ***,we obtain the precise location of the target ***,the measured values of the target borehole are consistent with the actual values,indicating that we can accurately evaluate a near-borehole geologic structure with scattered P-waves.

关键词： Acoustic logging Acoustic imaging Scattering exploration Beamforming

Risk and Potential:An Asset Allocation Framework with Applications to Robo-Advising

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Journal of the Operations Research Society of China 2022年第3期10卷 529-558页

作者： Xiang-Yu Cui Duan Li xiao qiao Moris S.Strub School of Statistics and Management Shanghai University of Finance and EconomicsShanghai200437China School of Data Science City University of Hong KongHong KongChina School of Data Science and Hong Kong Institute for Data Science City University of Hong KongHong KongChina Department of Information Systems and Management Engineering Southern University of Science and TechnologyShenzhen518055GuangdongChina

We propose a novel dynamic asset allocation framework based on a family of mean-variance-induced utility functions that alleviate the non-monotonicity and time-inconsistency problems of mean-variance *** utility functions are motivated by the equivalence between the mean-variance objective and a quadratic utility ***,our framework differs from mean-variance analysis in that we allow different treatment of upside and downside deviations from a target wealth *** naturally leads to a different characterization of possible investment outcomes below and above a target wealth as risk and *** proposed asset allocation framework retains two attractive features of mean-variance optimization:an intuitive explanation of the investment objective and an easily computed optimal *** establish a semi-analytical solution for the optimal trading strategy in our framework and provide numerical examples to illustrate its ***,we discuss applications of this framework to robo-advisors.

关键词： Mean-risk optimization Mean-variance Expected utility maximization Portfolio choice Risk Potential Robo-advising FinTech