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A magnetic model for low/hard state of black hole binaries

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Research in Astronomy and Astrophysics 2016年第3期16卷 33-42页

作者： Yong-Chun Ye Ding-Xiong Wang chang-yin Huang Xiao-Feng Cao School of Physics Huazhong University of Science and Technology School of Physics and Optoelectronic Engineering Yangtze University School of Physics and Electronic Information Hubei University of Education

A magnetic model for the low/hard state （LHS） of two black hole X-ray binaries （BHXBs）, H1743-322 and GX 339-4, is proposed based on transport of the magnetic field from a companion into an accretion disk around a black hole （BH）. This model consists of a truncated thin disk with an inner advection-dominated accretion flow （ADAF）. The spectral profiles of the sources are fitted in agreement with the data observed at four different dates corresponding to the rising phase of the LHS. In addition, the association of the LHS with a quasi-steady jet is modeled based on transport of magnetic field, where the Blandford-Znajek （BZ） and Blandford-Payne （BP） processes are invoked to drive the jets from BH and inner ADAE It turns out that the steep radio/X-ray correlations observed in H 1743-322 and GX 339-4 can be interpreted based on our model.

关键词： accretion accretion disks -- black hole physics -- magnetic field-- stars: individual (H 1743- 322) -- stars: individual (GX 339-4)

Determination of Pesticide Residue Cartap Using a Sensitive Fluorescent Probe

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Journal of Integrative Agriculture 2012年第11期11卷 1861-1870页

作者： JING Xu DU Li-ming WU Hao WU Wen-ying chang yin-xia Analytical and Testing Center Shanxi Normal University Linfen 041000 P.R.China

The insecticide cartap （CP） is non-fluorescent in aqueous solutions. This property makes its determination through direct fluorescent method difficult. In acidic medium and at room temperature, palmatine （PAL） can react with cucurbit[7]uril （CB[7]） to form stable complexes, and the fluorescence intensity of the complex is greatly enhanced. Significant quenching of the fluorescence intensity of the CB[7]-PAL complex was observed with the addition of cartap. Based on the significant quenching of the supramolecular complex fluorescence intensity, a new spectrofluorimetric method with high sensitivity and selectivity was developed to determine cartap in aqueous solution. The fluorescence quenching values （AF） showed good linear relationship with cartap concentrations from 0.009 to 2.4 ~tg mL-~ with a detection limit 0.0029 ~tg mE-x. The proposed method had been successfully applied to the determination of cartap residues in grain and vegetable with recoveries of 87.4-103%. In addition, the association constants of the complexes formed between the host and the guest were determined. The competing reaction and the supramolecular interaction mechanisms between the cartap and PAL as they fight for occupancy of the CB[7] cavity were studied using spectrofluorimetry, xH NMR and molecular modeling calculations.

关键词： cartap cucurbituril palmatine fluorescent probe

Observer-based Dynamic Local Piecewise Control of a Linear Parabolic PDE System with Non-collocated Pointwise Measurements 36

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Observer-based Dynamic Local Piecewise Control of a Linear P...

A local-optimization refinement algorithm in single particle analysis for macromolecular complex with multiple rigid modules

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作者： Ya-Qiang Liu Jun-Wei Wang chang-yin Sun School of Automation and Electrical Engineering University of Science and Technology Beijing

ISBN: (纸本)9781538629185

This paper presents an observer-based dynamic feedback control design for a linear parabolic partial differential equation（PDE） system, where a finite number of actuators and sensors are active over part thereof and at specified points in the spatial domain, respectively. In the proposed design method, a Luenberger-type PDE observer is first constructed by using the non-collocated pointwise measurements to exponentially tract the state of the PDE system. Based on the estimated state,a collocated local piecewise state feedback controller is then proposed. By employing Lyapunov direct method, integration by parts, Wirtinger’s inequality and first mean value theorem for integrals, a sufficient condition on exponential stability of the resulting closed-loop system is presented in term of standard linear matrix inequalities（LMIs）. Numerical simulation results are presented to show the effectiveness of the proposed design method.

关键词： Distributed parameter systems Piecewise control Pointwise measurement Lyapunov direct method Observerbased feedback control

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Protein & Cell 2016年第1期7卷 46-62页

作者： Hong Shan Zihao wang Fa Zhang Yong Xiong chang-Cheng yin Fei Sun Department of Biophysics College of Basic Medical Sciences Peking University Health Science Center Beijing 100191China National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China Key Lab of Intelligent Information Processing and Advanced Computing Research Lab Institute of Computing TechnologyChinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China Department of Molecular Biophysics and Biochemistry Yale University New Haven CT 06511 USA Center for Biological Imaging Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

Single particle analysis, which can be regarded as an average of signals from thousands or even millions of particle projections, is an efficient method to study the three-dimensional structures of biological macro- molecules. An intrinsic assumption in single particle analysis is that all the analyzed particles must have identical composition and conformation. Thus specimen heterogeneity in either composition or conformation has raised great challenges for high-resolution analysis. For particles with multiple conformations, inaccurate align- ments and orientation parameters will yield an averaged map with diminished resolution and smeared density. Besides extensive classification approaches, here based on the assumption that the macromolecular complex is made up of multiple rigid modules whose relative orien- tations and positions are in slight fluctuation around equilibriums, we propose a new method called as local optimization refinement to address this conformational heterogeneity for an improved resolution. The key idea is to optimize the orientation and shift parameters of each rigid module and then reconstruct their three-dimen- sional structures individually. Using simulated data of 80S/70S ribosomes with relative fluctuations between the large （60S/50S） and the small （40S/30S） subunits, we tested this algorithm and found that the resolutions of both subunits are significantly improved. Our method provides a proof-of-principle solution for high-resolutionsingle particle analysis of macromolecular complexes with dynamic conformations.

关键词： cryo-electron microscopy single particleanalysis conformational heterogeneity rigid module Iocaoptimization refinement

OsELF3 Is Involved in Circadian Clock Regulation for Promoting Flowering under Long-Day Conditions in Rice

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Molecular Plant 2013年第1期6卷 202-215页

作者： ying Yang Qiang Peng Guo-Xing Chen Xiang-Hua Li chang-yin Wu National Key Laboratory of Crop Genetic Improvement National Center of Plant Gene Research (Wuhan) Huazhong Agricultural University Wuhan430070 China

Heading date is a critical trait that determines cropping seasons and regional adaptability in rice （Oryza sativa）. Research efforts during the last decade have identified some important photoperiod pathway genes that are conserved between Arabidopsis and rice. In this study, we identified a novel gene, Oryza sativa ELF3 （OsELF3）, which is a putative homolog of the ELF3 gene in Arabidopsis thaliana. OsELF3 was required for the control of heading date under long-day conditions. Its Tos17-tagging mutants exhibited a delayed heading date phenotype only under long-day, but not short-day, conditions. OsELF3 was highly expressed in leaf blades, and the OsELF3 protein was localized in the nucleolus. An obvious diurnal rhythm of OsELF3 transcript level was observed, with a trough in the early day and a peak in the late night in wild-type plants. However, this expression pattern was disrupted in oself3 mutants. Further inves- tigations showed that the expression of OsGI and Ghd7 was up-regulated in the oself3 mutant, indicating that OsELF3 acts as a negative regulator upstream of OsGI and Ghd7 in the flowering-time control under long-day conditions. The rhythmic expression of circadian clock-related genes, including some OsPRR members, was obviously affected in oself3 mutants. Our results indicated that OsELF3 acts as a floral activator in the long-day photoperiodic pathway via its cross- talk with the circadian clock in rice.

关键词： heading date photoperiod pathway circadian clock rice.

Synthesis,crystal structures and complexing ability of difunctionalized copillar[5]arene Schiff bases

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Chinese Chemical Letters 2017年第2期28卷 431-436页

作者： chang-Bo yin ying Han Gui-Fei Huo Jing Sun Chao-Guo Yan College of Chemistry & Chemical Engineering Yangzhou University Yangzhou 225002 China

An efficient method for the synthesis of some difunctionalized copillar[5]arene Schiff bases from condensation of salicylaldehyde and its 5-chloro,5-bromo,3,5-di（t-butyl） substituted derivatives with corresponding diamino-functionalized copillar[5]arene,which were prepared by Gabriel reaction according to the reported ***-crystals of six copillar[5]arenes were determined by X-ray *** ORTEP of compounds showed that the two chains units of Schiff base exist in the outside of the cavity of pillar[5]***,the complexing ability of these Schiff bases to transition metal ions were investigated by UV and fluorescence spectroscopy.

关键词： Pillararene Schiff base Metal complex Single crystal structure Fluorescence

Joint Downlink Scheduling and Radio Resource Allocation for User-Individual QoS in Adaptive OFDMA Wireless Communication Systems

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 1-5页

作者： LU Yan-hui YUAN Shu-chong yin chang-chuan YUE Guang-xin School of Telecommunications Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

This paper proposes and analyzes a downlink multi-carrier proportional fair scheduler and an adaptive radio resource allocation algorithm combining the scheduler. This scheduler and algorithm are suitable for orthogonal frequency division multiple access wireless communication systems supporting multiple quality of service classes. Our results demonstrate that the scheduler and algorithm provide user-explicit fairness with user-individual quality of service guarantees, but the joint schheme achieves a higher sum-rate capacity with flexible parameter settings compared with the multi-carrier proportional fair scheduler.

关键词： OFDMA adaptive radio resource allocation scheduling QoS

Accurate structural descriptor enabled screening for nitrogen and oxygen vacancy codoped TiO_(2) with a large bandgap narrowing

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Journal of Materials Science & Technology 2022年第27期122卷 84-90页

作者： Kangyu Zhang Lichang yin Gang Liu Hui-Ming Cheng Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Department of Physics and Electronic Information Huaibei Normal UniversityHuaibei 235000China

Nitrogen(N)doping has been widely adopted to improve the light absorption of TiO_(2).However,the newly introduced N-2p states are largely localized thus barely overlap with O-2p states in the valence band of TiO_(2),resulting in a shoulder-like absorption *** realize an apparent overlap between N-2p and O-2p states,charge compensation between N^(3-)and O^(2-)via electron transfer from oxygen vacancies(VO)to N dopants is one possible *** verify this,in numerous doping configurations of N/VO-codoped anatase TiO_(2),we identified two types of VOposition independent N-dopant spatial orderings by efficient screening enabled with a newly designed structural *** with others,these two types of the N-dopant spatial orderings are highly beneficial for charge compensation to produce an apparent overlap between N-2p and O-2p states,therefore achieving a large bandgap ***,the two types of the N-dopant spatial orderings can also be generalized to N/VO-codoped rutile TiO_(2)for bandgap narrowing.

关键词： Structural descriptor TiO_(2) Bandgap narrowing Doping Machine learning Density functional theory

Microscopic sand production simulation and visual sanding pattern description in weakly consolidated sandstone reservoirs

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Petroleum Science 2022年第1期19卷 279-295页

作者： chang-yin Dong Bo Zhou Fan-Sheng Huang Lei Zhang Yi-Zhong Zhao Yang Song Jun-Yu Deng Key Laboratory of Unconventional Oil&Gas Development Ministry of EducationQingdao266580ShandongPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Research Institute of Petroleum Engineering Technology Shengli BranchSINOPECDongying257000ShandongPR China Research Ltd.of Engineering Technology CNPCTianjin345000PR China

To visually describe the sanding pattern,this study constructs a new particle-scale microstructure model of weakly consolidated formation,and develop the corresponding methodology to simulate the sanding process and predict sand cavity *** microstructure model is a particle-objective model,which focuses on the random sedimentation of every sand *** the microstructure,every particle has its own size,sphericity and inclination *** is used to simulate the actual structure of cemented granular materials,which considers the heterogeneity and randomness of reservoir properties,provides the initial status for subsequent sanding *** the particle detachment criteria,the microscopic simulation of sanding can be visually implemented to investigate the pattern and cavity shapes caused by sand *** results indicate that sanding always starts initially from the borehole border,and then extends along the weakly consolidated plane,showing obvious characteristic of *** typical microscopic sanding patterns,concerning pore liquefaction,pseudo wormhole and continuous collapse,are proposed to illustrate the sanding mechanism in weakly consolidated *** nonuniformity of sanding performance depends on the heterogeneous distribution of reservoir properties,such as rock strength and particle ***,the three sanding patterns are verified by visually experimental *** proposed integrated methodology is capable of predicting and describing the sanding cavity shape of an oil well after long-term sanding production,and providing the focus objective of future sand control measure.

关键词： Weakly consolidated reservoir Particle-scale microstructure model Microcosmic sanding process simulation Visual sanding cavity description Sanding prediction Sand control optimization