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经ERCP胆道金属支架植入治疗不可切除肝外胆道恶性梗阻的安全性及疗效评价

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中国内镜杂志 2018年第3期24卷 27-31页

作者：陈磊吴益峰蒋存兵陈明良李定耀宁波大学医学院附属鄞州医院肝胆外科浙江宁波315040

目的探讨经内镜逆行胰胆管造影(ERCP)胆道金属支架置入对于肝外胆道恶性梗阻的临床疗效及安全性。方法根据患者手术方法不同将40例恶性胆道梗阻患者分为经皮经肝胆管穿刺引流术(PTCD)组和ERCP组。PTCD组患者接受PTCD治疗,ERCP组患者接受... 详细信息

目的探讨经内镜逆行胰胆管造影(ERCP)胆道金属支架置入对于肝外胆道恶性梗阻的临床疗效及安全性。方法根据患者手术方法不同将40例恶性胆道梗阻患者分为经皮经肝胆管穿刺引流术(PTCD)组和ERCP组。PTCD组患者接受PTCD治疗,ERCP组患者接受ERCP置入金属支架治疗。结果两组生存时间差异有统计学意义(P<0.05)。ERCP组术后胆道通畅时间明显长于PTCD组,差异有统计学意义(P<0.05)。ERCP组住院时间明显少于PTCD组(P<0.05)。术后1周ERCP组肝功能检测指标明显优于PTCD组(P<0.05)。此外,PTCD组和ERCP组的并发症发生率分别30.0%与10.0%。ERCP组的并发症发生率明显低于PTCD组(P<0.05)。结论 ERCP支架置入与PTCD解除胆道恶性梗阻疗效相似。但是,ERCP术后胆道通畅时间长,并发症少,患者肝功能指标恢复快。因此,对于肝外胆道恶性梗阻的患者,采用ERCP临床疗效更好,安全性更高。

关键词：恶性胆道梗阻经内镜逆行胰胆管造影外科手术支架

Using Chebyshev polynomial interpolation to improve the computational efficiency of gravity models near an irregularly-shaped asteroid

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Research in Astronomy and Astrophysics 2017年第12期17卷 15-26页

作者： Shou-cun Hu jiang-Hui Ji CAS Key Laboratory of Planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

In asteroid rendezvous missions, the dynamical environment near an asteroid’s surface should be made clear prior to launch of the mission. However, most asteroids have irregular shapes,which lower the efficiency of calculating their gravitational field by adopting the traditional polyhedral method. In this work, we propose a method to partition the space near an asteroid adaptively along three spherical coordinates and use Chebyshev polynomial interpolation to represent the gravitational acceleration in each cell. Moreover, we compare four different interpolation schemes to obtain the best precision with identical initial parameters. An error-adaptive octree division is combined to improve the interpolation precision near the surface. As an example, we take the typical irregularly-shaped nearEarth asteroid 4179 Toutatis to demonstrate the advantage of this method; as a result, we show that the efficiency can be increased by hundreds to thousands of times with our method. Our results indicate that this method can be applicable to other irregularly-shaped asteroids and can greatly improve the evaluation efficiency.

关键词： minor planets,asteroids:individual(4179 Toutatis) methods:numerical Chebyshev polynomials

Mineral association and graphite inclusions in nephrite jade from Liaoning, northeast China: Implications for metamorphic conditions and ore genesis

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Geoscience Frontiers 2019年第2期10卷 425-437页

作者： cun Zhang Xiaoyan Yu Tianlong jiang School of Gemology China University of Geosciences (Beijing)

The Liaoning Province in the northeastern part of the North China Craton(NCC) hosts several tremolite jade(nephrite) deposits. Here we investigate the Sangpiyu tremolite jade deposit where the relationship between abundant graphite inclusions within the jade remains enigmatic. We employ petrography, electron probe microanalysis, X-ray-diffraction, and Raman spectroscopy to characterize the tremolite jade and its inclusion minerals. The Sangpiyu jade is predominately composed of tremolite with minor calcite, dolomite, serpentine, titanite, zoisite, allanite, chlorite,apatite, chromite and graphite. Raman spectroscopy of graphite inclusions shows that the D1/G intensity ratio ranges from 0.78 to 0.88 in deep green samples and from 0.05 to 0.23 in dark green samples. The ranges of D1/(D1 + G) integral area ratio for these types are from 0.0548 to 0.3037 and 0.5528 to 0.7355 respectively. The formation temperature of graphite inclusions in the dark green tremolite jade is computed as 549.8 ℃, whereas that for the deep green sample is about343.2 ℃. Our results suggest that the jade formation occurred in a multi-stage process through the action of hydrothermal fluids and metamorphism possibly in a subduction-related setting at moderate to high temperatures.

关键词： Tremolite jade Petrology and Raman spectroscopy Graphite Sangpiyu North China

Maximizing deviation method for multiple attribute decision making under q-rung orthopair fuzzy environment

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Defence Technology（防务技术） 2020年第5期16卷 1073-1087页

作者： Jie Wang Gui-wu Wei cun Wei jiang Wu School of Business Sichuan Normal UniversityChengdu610101PR China School of Statistics Southwestern University of Finance and EconomicsChengdu611130PR China

Because of the uncertainty and subjectivity of decision makers in the complex decision-making environment,the evaluation information of alternatives given by decision makers is often fuzzy and *** a generalization of intuitionistic fuzzy set(IFSs)and Pythagoras fuzzy set(PFSs),q-rung orthopair fuzzy set(q-ROFS)is more suitable for expressing fuzzy and uncertain ***,in actual multiple attribute decision making(MADM)problems,the weights of DMs and attributes are always completely unknown or partly known,to date,the maximizing deviation method is a good tool to deal with such ***,combine the q-ROFS and conventional maximizing deviation method,we will study the maximizing deviation method under q-ROFSs and q-RIVOFSs in this ***,we briefly introduce the basic concept of q-rung orthopair fuzzy sets(q-ROFSs)and q-rung interval-valued orthopair fuzzy sets(q-RIVOFSs).Then,combine the maximizing deviation method with q-rung orthopair fuzzy information,we establish two new decision making *** this basis,the proposed models are applied to MADM problems with q-rung orthopair fuzzy *** with existing methods,the effectiveness and superiority of the new model are *** method can effectively solve the MADM problem whose decision information is represented by q-rung orthopair fuzzy numbers(q-ROFNs)and whose attributes are incomplete.

关键词： Multiple attribute decision making(MADM) q-rung orthopair fuzzy sets(q-ROFSs) q-rung interval-valued orthopair fuzzy sets (q-RIVOFSs) Maximizing deviation method Building materials

Micromechanical Behavior and Failure Mechanism of F / B Multi-phase High Performance Steel

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Journal of Iron and Steel Research International 2016年第5期23卷 489-494页

作者： cun-jiang TANG Shi-long LIU Cheng-jia SHANG School of Materials Science and Engineering University of Science and Technology Beijing

The deformation and micro-voids formation mechanisms in ferrite / bainite（ F / B） multi-phase steel with the volume fraction of bainite less than 50% were studied by numerical simulation and experimental observation. The results show that the micro-strain concentrates at the soft / hard phase（ F / B） interface in the multi-phase steel,which should be correlated with the mechanism of incoordinate deformation. During the necking of the steel,the micro-voids initially form around the F / B interface,which also form in ferrite and bainite with the severe strain. The micro-voids in bainite are more dense and finer than those in ferrite. The failure mechanism of bainite is the coalescence of micro-voids,and the failure mechanism of ferrite is the growth and tearing of micro-voids. Due to the different failure mechanisms of ferrite and bainite,a suitable part of soft phase would be beneficial to the capability of anti-failure of F / B multi-phase steel during the ductile fracture.

关键词： ferrite / bainite multi-phase steel numerical simulation ferrite / bainite interface micro-strain micro-void failure mechanism soft phase

Numerical modeling of tidal currents,sediment transport and morphological evolution in Hangzhou Bay,China

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International Journal of Sediment Research 2013年第3期28卷 316-328页

作者： Dong-feng XIE Shu GAO Zheng-bing WANG cun-hong PAN Zhejiang Institute of Hydraulics & Estuary Key Laboratory for Coast and Island Development Ministry of EducationNanjing University Chang jiang Scholar State Key Laboratory of Estuarine and Coastal ResearchEast China Normal University Delft University of Technology Faculty of Civil Engineering and Geosciences

A 2D depth-averaged numerical model is set up to simulate the macro-scale hydrodynamic characteristics,sediment transport patterns and morphological evolution in Hangzhou Bay,a large macro-tidal estuary on the eastern coast of *** incorporating the shallow water equations,the suspended sediment transport equation and the mass-balance equation for sediment;short-term hydrodynamics,sediment transport and long-term morphological evolution for Hangzhou Bay are simulated and the underlying physical mechanisms are *** model reproduces the spatial distribution patterns of suspended sediment concentration(SSC) in Hangzhou Bay,characterized by three high SSC zones and two low SSC *** also correctly simulates the residual flow,the residual sediment transport and the sediment accumulation patterns in Hangzhou *** model results are in agreement with previous studies based on field *** residual flow and the residual sediment transport are landwards directed in the northern part of the bay and seawards directed in the southern *** accumulation takes place in most areas of the *** analysis revealed that the tide is flood-dominant in the northern part of the bay and ebb-dominant in the southern part of the *** strength of the flood-dominance increases landwards along the northern Hangzhoii *** turn sediment transport in Hangzhou Bay is controlled by this tidal asymmetry *** addition,the direction of tidal propagation in the East China Sea,the presence of the archipelago in the southeast and the funnel-shaped geometry of the bay,play important roles for the patterns of sediment transport and sediment accumulation respectively.

关键词： Hangzhou Bay Tidal currents Sediment dynamics Estuary Morphology Numerical modeling

Application of a new semi-analytical method to periodic motion due to the J_(22) tesseral harmonic

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Research in Astronomy and Astrophysics 2015年第6期15卷 896-908页

作者： Shou-cun Hu jiang-Hui Ji Yu-Hui Zhao Key Laboratory of Planetary Sciences Purple Mountain Observatory Chinese Academy of Sciences

We revisit the issue of constructing the first-order periodic solution that incorporates the J22 tesseral harmonic and developing a new semi-analytical solution that may apply to any orbital eccentricity in [0,1）. In our work, the solution is expressed in a finite compact form composed of several definite integrals with varying integration intervals constrained in [0,Tr], in which the traditional Hansen coefficients are no longer involved. Numerical experiments are also given and compared with the traditional series expansion method, and the results show that the derived solution is capable of dealing with highly eccentric orbits. Therefore, the solution given can provide a new technique to analyze the perturbation characteristics arising from the J22 harmonic.

关键词： celestial mechanics

Propagation patterns of microseismic waves in rock strata during mining:an experimental study

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International Journal of Minerals,Metallurgy and Materials 2019年第5期26卷 531-537页

作者： Dong Li Jun-fei Zhang cun-wen Wang Fu-xing jiang School of Civil and Resources Engineering University of Science and Technology Beijing School of Civil Environmental and Mining Engineering The University of Western Australia

Microseismic monitoring has been widely used in mines for monitoring and predicting dynamic disasters such as rockbursts and waterbursts. However, to develop high-precision microseismic monitoring systems, the propagation patterns of microseismic waves under complex geological conditions must be elucidated. To achieve this aim, a simulation model of a typical coalmine was designed using similar materials according to the similarity theory to simulate the mining process. Geophones were embedded into the model to detect the propagation of elastic waves from microseisms. The results show that in an unmined solid rock mass, the wave velocity in shallow rock strata is mainly affected by geologically weak planes, whereas in deep strata it is affected mainly by the density of the rock mass. During propagation, the amplitude first decreases and then increases rapidly with increasing propagation distance from the coal layer. After mining, our results indicate that the goaf causes significant attenuation of the wave velocity. After the goaf was backfilled, the velocity attenuation is reduced to some extent but not eliminated. The results of this study can be used as guidelines for designing and applying microseismic monitoring systems in mines.

关键词： similar-materials simulation microseismic monitoring elastic wave velocity amplitude propagation

Overpressure and gas charging in tight sandstone:Xujiahe Formation,northeastern Sichuan Basin

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Petroleum Science 2022年第6期19卷 2583-2600页

作者： Jing-Dong Liu cun-Jian Zhang You-Lu jiang Guo-Shuai Bai Shandong Provincial Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong266580China Shandong Provincial Key Laboratory of Reservoir Geology China University of Petroleum(East China)QingdaoShandong266580China School of Geosciences China University of Petroleum(East China)QingdaoShandong266580China

Overpressure is a key factor for oil and gas charging in tight reservoirs,but it is still a challenge to evaluate the overpressure evolution and its control on oil and gas *** Xujiahe Formation in the northeastern Sichuan Basin as an example,this paper presented a method for evaluating overpressure and its effect on natural gas charging in tight sandstone in compressional *** abnormally high pressure and its causes were analyzed by measured data and logging *** calculation and PVT simulation were used to investigate the amounts of overpressure resulted from hydrocarbon generation and tecto nic compression,*** the source rock-reservoir pressu re differences were calculated and the characteristics of natural gas charging during the natural gas charging periods were *** was revealed that hydrocarbon generation and tectonic compression were the main causes of the *** overpressure of both source rocks and reservoir exhibited a gradually increasing trend from Middle Jurassic to Early Cretaceous(J2-K1),then decreased since Later Cretaceous(K2),and some of that preserved to *** contributions of the hydrocarbon generation and tectonic compression to overpressure were different in different *** residual pressure difference between the source rocks and the reservoir is the major driving force for tight sandstone gas *** main hydrocarbon generating area of the source rocks and the area of high driving force were major natural gas enrichment areas,and the driving force determined the natural gas charging space in the pore throat system of the *** research helps evaluate the overpressure and pressure difference between source rocks and reservoir in compressed basin,as well as investigate the effective pore throat space of tight gas charging by the driver of overpressure.

关键词： Tight sandstone gas Overpressure Hydrocarbon generation Tectonic compression Driving force for tight gas charging Sichuan Basin