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Applied Mathematics and Mechanics(English Edition) 2010年第7期31卷 861-874页

作者：陈豫眉谢小平 School of Mathematics Sichuan University College of Mathematics and Information China West Normal University

A nonconforming finite element method of finite difference streamline diffusion type is proposed to solve the time-dependent linearized Navier-Stokes equations. The backward Euler scheme is used for time discretization. Crouzeix-Raviart nonconforming finite element approximation, namely, nonconforming （P1）2 - P0 element, is used for the velocity and pressure fields with the streamline diffusion technique to cope with usual instabilities caused by the convection and time terms. Stability and error estimates are derived with suitable norms.

关键词： streamline diffusion method finite difference method nonconforming finite element method time-dependent linearized Navier-Stokes equations error estimate

Vertical dynamic response of the ballastless track on long-span plate-truss cable-stayed bridges

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Science China(Technological Sciences) 2015年第2期58卷 236-247页

作者： LI Yong Le SU Yang XIA Fei Long ZHANG Nan Department of Bridge Engineering Southwest Jiaotong University MOE Key Laboratory of High Speed Railway Engineering Southwest Jiaotong University Department of Bridge Engineering Northern Jiaotong University

An analytical model is presented to study vertical dynamic response of the ballastless track on long-span plate-truss cable-stayed bridges based on an explicit dynamic analysis *** the model,the train,ballastless track and bridge are treated as a coupled vibration system with *** simulating the dynamic process of the system,this paper discusses the distribution law of dynamic responses of the bridge deck and the bed *** shows the necessity of a base plate for the ballastless track on the long-span plate-truss cable-stayed *** of the influence of different train speeds and stiffness of the elastic vibration-damping pad on the dynamic responses of the bridge deck and the bed slab is also *** reasonable stiffness value of elastic vibration-damping pad is proposed.

关键词： long-span cable-stayed bridge plate-truss girder ballastless track train-induced vibration vehicle-bridge system

Micromagnetic simulation of Sm–Co/α-Fe/Sm–Co trilayers with various angles between easy axes and the film plane

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Chinese Physics B 2014年第9期23卷 439-445页

作者：张溪超赵国平夏静岳明袁新红谢林华 College of Physics and Electronic Engineering Sichuan Normal University

Hysteresis loops and energy products have been calculated systematically by a three-dimensional （3D） software OOMMF for Sm-Co/α-Fe/Sm-Co trilayers with various thicknesses and β, where β is the angle between the easy axis and the field applied perpendicular to the film plane. It is found that trilayers with a perpendicular anisotropy possess considerably larger coercivities and smaller remanences and energy products compared with those with an in-plane anisotropy. Increase of β leads to a fast decrease of the maximum energy product as well as the drop of both remanence and coercivity. Such a drop is much faster than that in the single-phased hard material, which can explain the significant discrepancy between the experiment and the theoretical energy products. Some modeling techniques have been utilized with spin check procedures performed, which yield results in good agreement with the one-dimensional （1D） analytical and experimental data, justifying our calculations. Further, the calculated nucleation fields according to the 3D calculations are larger than those based on the 1D model, whereas the corresponding coercivity is smaller, leading to more square hysteresis loops and better agreement between experimental data and the theory.

关键词： micromagnetic simulation hard/soft trilayers hysteresis loops magnetization configuration

Characterization of codon usage bias in the dUTPase gene of duck enteritis virus

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Progress in Natural Science:Materials International 2008年第9期18卷 1069-1076页

作者： Lichan Zhao a, Anchun Cheng a,b,, Mingshu Wang a,b,, Guiping Yuan c, Mingsheng Caia a Avian Disease research Center, College of Veterinary Medicine of sichuan Agricultural University, Xinkang Road 46, Ya’an, sichuan 625014, China b Key Laboratory of Animal Disease and Human Health of sichuan province, Ya’an 625014, China c Analytical & Testing Center, sichuan University, Chengdu 610064, China Avian Disease research Center College of Veterinary Medicine of Sichuan Agricultural University Xinkang Road 46 Ya’an Sichuan 625014 China Key Laboratory of Animal Disease and Human Health of sichuan province Ya’an 625014 China Analytical & Testing Center Sichuan University Chengdu 610064 China

A comparative analysis of the codon usage bias in the newly discovered dUTPase gene (Assigned Accession No.:DQ486149) of the duck enteritis virus (DEV) and the dUTPase gene of 32 reference herpesviruses was *** results indicated that the DEV dUT-Pase gene encodes a protein of 477 amino acids, which includes five conserved motifs with a 3-1-2-4-5 *** codon adap-tation index (CAI), efiective number of codons (ENC), and GC3S values indicated synonymous codon usage bias in the dUTPase gene of herpesviruses, and this synonymous bias was correlated with host *** codon usage patterns of the DEV dUTPase gene were phylogenetically conserved and similar to that of the dUTPase genes of the avian *** codon usage in each micro-organism was difierent, there were no strain-specific difierences among ***-one codons in the predicted polypeptide, with a strong bias towards A and T at the third codon position, were *** of the codon usage in the dUTPase gene of difierent organisms revealed that there were 19 codons showing distinct codon usage difierences between the DEV and Escherichia coli dUTPase genes;16 between the DEV and yeast dUTPase genes;and 15 between the DEV and human dUTPase *** of variance (ANOVA) showed significant difierences between the DEV and yeast dUTPase genes (r = 0.536, P < 0.01).The extent of codon usage bias in the DEV dUTPase gene was highly correlated with the gene expression level, therefore the results may provide useful information for gene classification and functional studies.

关键词： DEV dUTPase Codon usage bias EMBOSS

A magnetic hydroxyapatite composite scaffoldbased magnetic therapy for bone repair:an experimental study in canis lupus familiaris

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Regenerative Biomaterials 2017年第2期4卷 97-103页

作者： Jing He Hao Hu Xiaobo Zeng Fang Lan Fang Wu Yao Wu National Engineering research Centre for Biomaterials Sichuan UniversityChengdu 610064PR China

While the beneficial effect of magnetic nanoparticle on the biological functions of calcium phosphate scaffolds has been well documented,little is known about the effect of magnetic nanoparticle on the in vivo performance of hydroxyapatite(HA)*** this study,to further investigate the influence of magnetic hydroxyapatite(MHA)scaffolds on bone repair and the interactions between the magnetic scaffolds and the exterior magnetic field in vivo,we implanted the scaffolds into a beagle dog experimental model of femur transverse *** with traditional HA scaffolds,the MHA scaffolds could accelerate bone tissue regeneration in situ,especially in the first ***,it had a synergic effect between external magnetic fields and MHA scaffolds on bone repair in *** 1 month,the bone density on MHA exposed to an external magnetic field was roughly 30%greater than that of HA,and only slightly less than the bone density observed on HA after 3 ***,the results suggest the improvement of bone ingrowth is critical for HA scaffold with magnetic fields,which is significant for the early bone fixation and repair.

关键词： magnetic nanoparticles static magnetic fields magnetic hydroxyapatite bone regeneration

A two-photon mitotracker based on a naphthalimide fluorophore:Synthesis, photophysical properties and cell imaging

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Chinese Chemical Letters 2014年第7期25卷 1001-1005页

作者： Yong Dai Bao-Kuo Lv Xin-Fu Zhang Yi Xiao Department of Criminal Science and Technology Sichuan Police College State Key Laboratory of Fine Chemicals Dalian University of Technology Liaoning Water Environment Monitoring Center Shenyang Branch

PAHPN. a naphthalimide-based mitotracker with reasonable two-photon excitation emission activity and polarity-sensitive fluorescence properties has been efficiently synthesized and studied in twophoton, co-localizatio... 详细信息

关键词： Mitotracker Mitochondria Namphthalimide Two-photon Fluorescence imaging

Efficient Priority Packet Recovery Based on Network Coding in DVB-IPDC System

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China Communications 2015年第7期12卷 167-178页

作者： WANG Lian PENG Daiyuan LIANG Hongbin Provincial Key Laboratory of Information Coding and Transmission School of Information Science and TechnologySouthwest Jiaotong University College of Computing Science and Technology Chongqing University of Posts and Telecommunications School of Transportation and Logistics Southwest Jiaotong University Secure Networking and Computing Institute School of Computing Informatics and Decision Systems EngineeringArizona State University

In DVB-IPDC system, due to the constraints of handheld devices and the broadcast nature of wireless network, packet loss is inevitable. ECDR-NC proposed is a retransmission encoding packet selection algorithm based on the dynamic information updating, which can find the current most effective complete decoding packet. ECDR-NC can not only avoid the redundant encoding packets due to the overlapping among encoding packets, but also reduce the computational complexity compared with the traditional encoding schemes. Furthermore, the retransmission upper bound of ECDR-NC is fully controlled. In time-sensitive applications, to maximize the aggregate number of recovery packets while minimizing the total number of discarded packets due to the time limit according to the priority preference, the adaptive priority scheme EPNC is formulized, and the weighted relation graph is constructed to find the maximum-weighted encoding packets sequence according to the decoding gains. In the same network environment, the performances comparisons between PNC and EPNC show that EPNC is more efficient and more rational, and the average discarded packets ratios ofEPNC can be reduced about 18%~27%. The main contributions of this paper are an effective retransmission encoding packet selection algorithm ECDR-NC proposed, and a new adaptive priority recovery scheme EPNC introduced into DVB-IPDC system.

关键词： digital video broadcasting(DVB) retransmission network coding(NC) longterm evolution(LTE) wireless network

CO sensing properties of a cubic ZnSn(OH)_6 synthesized by hydrothermal method

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Chinese Chemical Letters 2016年第3期27卷 464-466页

作者： Hu Wang Xiao-Xiong Liu Juan Xie Ming Duan Jun-Lei Tang College of Materials Science and Engineering Southwest Petroleum University (SWPU) College of Chemistry and Chemical Engineering SWPU

In this work, ZnSn（OH）6with a cubic structure is successfully synthesized by one-step hydrothermal method without any catalyst. The response and recovery characteristics of gas sensing were investigated against various gases via quartz crystal microbalance（QCM） at room temperature. The sensor exhibited high sensitivity and good selectivity toward CO gas. Moreover, a linear dependence of log^（àDelta F）about CO concentration was obtained. It is demonstrated that the QCM sensor coated cubic ZnSn（OH）6could be a suitable candidate for detecting CO.

关键词： ZnSn(OH)6 Gas sensing Hydrothermal method Cubic structure QCM

Spatial distribution of soil hydraulic parameters estimated by pedotransfer functions for the Jialing River Catchment,Southwestern China

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Journal of Mountain Science 2016年第1期13卷 29-45页

作者： LEI Wen-Juan TANG Xiang-Yu Brian J.REID ZHOU Xiang-Yang Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China School of Environmental Sciences University of East AngliaNorwich NR4 7T JUK College of Water Resource&Hydropower University of SichuanChengdu 610065China

Soil hydraulic parameters θs,α,n,Ks,L and θr of the van Genuchten-Mualem model were estimated using three pedotransfer functions(PTFs) based on soil properties for surface soils of the largest main tributary catchment(the Jialing River) of the upper Yangtze River in *** soil database was from the second national soil survey of China with a spatial 30 × 30 arc-second *** to the statistical analysis of the differences between the continuous-PTFs-estimated values of soil hydraulic parameters for the study catchment and the reference values for a specific texture class provided in the development database of a specific PTF,best estimations were obtained using the W?sten *** Rawls & Brakenssiek PTF was good estimation for parameter θr that was assumed as zero by W?sten *** established higher θr(0.08%) and lower Ks(20 cm/d) and θs(0.43%) in the mid-downstream area relative to the other areas of the catchment could lead to larger amounts of surface runoff andconsequently provide higher energy to erode ***,these factors provide a supporting explanation for previously reported severe soil erosion occurring in this *** heterogeneity analysis for estimated hydraulic parameters in terms of semivariogram showed that the spatial correlation distance was in the range of 50-80 km and that the spatial variability(sill) was not large except for parameters Ks and *** semi-variance with the exponential model at the zero distance(nugget) was 30%-50% of the *** study provided a practical PTF approach for estimating soil hydraulic properties from soil survey data at a large watershed *** estimation results could provide better insight into the mechanism of surface runoff and soil erosion,which is important to better understand and manage erosion in the catchment.

关键词： hydraulic catchment erosion downstream runoff texture exponential heterogeneity watershed fitted

Characteristics and genesis of the Feixianguan Formation oolitic shoal reservoir, Puguang gas field, sichuan Basin, China

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Frontiers of Earth Science 2015年第1期9卷 26-39页

作者： Peiyuan CHEN Xiucheng TAN Huiting YANG Ming TANG Yiwei JIANG Xiuju JIN Yang YU State Key Laboratory of Oil and Gas Geology and Exploration Southwest Petroleum University Chengdu 610500 China School of Geoscience and Technology Southwest Petroleum University Chengdu 610500 China research Institute of Petroleum Exploration and Development SINOPEC Zhongyuan Oilfield Company Puyang 457001 China

The Lower Triassic Feixianguan Formation at the well-known Puguang gasfield in the northeastern sichuan Basin of southwest China produces a representa- tive oolitic reservoir, which has been the biggest marinesourced gasfield so far in China （discovered in 2003 with proven gas reserves greater than 350× 10^8 m3）. This study combines core, thin section, and scanning electron microscopy observations, and geochemical analysis （C, O, and Sr isotopes） in order to investigate the basic characteristics and formation mechanisms of the reservoir. Observations indicate that platform margin oolitic dolomites are the most important reservoir rocks. Porosity is dominated by intergranular and intragranular solution, and moldic pore. The dolomites are characterized by medium porosity and permeability, averaging at approximately 9% and 29.7 mD, respectively. ^87Sr/^86Sr （0.707536-0.707934） and δ^13CpDB （1.8 ‰--3.5 ‰） isotopic values indicate that the dolomitization fluid is predominantly concentrated seawater by evaporation, and the main mechanism for the oolitic dolomite formation is seepage reflux at an early stage of eodiagenesis. Both sedimentation and diagenesis （e.g., dolomitization and dissolution） have led to the formation of high-quality rocks to different degrees. Dolomite formation may have little contribution, karst may have had both positive and negative influences, and burial dissolution-TSR （thermochemical sulfate reduction） may not impact widely. The preservation of primary intergranular pores and dissolution by meteoric or mixed waters at the early stage of eogenesis are the main influences. This study may assist oil and gas explorationactivities in the Puguang area and in other areas withdolomitic reservoirs.

关键词： oolite shoal reservoir carbonate diagenesis,Triassic Feixianguan Formation Puguang gas field sichuan Basin