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奎的平与氯氮平对脑电图影响的对照观察

实用医技杂志 2005年第2B期12卷 482-484页

作者：袁凤娟高明政刘欣刘振东临沂市精神卫生中心山东临沂276005

目的:探讨奎的平与氯氮平对脑电图的影响及差异性。方法:符合CCMD-2-R诊断的精神分裂症患者130例,服用奎的平、氯氮平治疗各65例,分别于服药后2周、4周、6周进行脑电图检测,采用阳性与阴性症状量表(PANSS)观察疗效。结果:奎的平组脑电... 详细信息

目的:探讨奎的平与氯氮平对脑电图的影响及差异性。方法:符合CCMD-2-R诊断的精神分裂症患者130例,服用奎的平、氯氮平治疗各65例,分别于服药后2周、4周、6周进行脑电图检测,采用阳性与阴性症状量表(PANSS)观察疗效。结果:奎的平组脑电图异常率29.2%,氯氮平组脑电图异常率80.0%,两组比较差异具有显著性意义(P<0.01),两组药物脑电图异常改变率与临床疗效无关。结论:奎的平可引起脑电图异常改变,但其异常程度显著低于氯氮平。

关键词：精神分裂症奎的平氯氮平脑电图

Review on the challenges and strategies in oil and gas industry's transition towards carbon neutrality in China

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Petroleum Science 2023年第6期20卷 3931-3944页

作者： Qi Zhang Jiang-feng Liu Zhi-Hui gao Si-yuan Chen Bo-Yu Liu School of Business Administration China University of Petroleum(Beijing)at KaramayKaramay834000XinjiangChina School of Economics and Management China University of Petroleum(Beijing)Beijing102249China Tianshan Research Institute Karamay834000XinjiangChina School of Economics and Management North China Electric Power UniversityBeijing102206China

In light of carbon-neutral pledge, the oil and gas industry has been facing several critical new challenges in China. The current status and new challenges in terms of market mechanism reform, supply-consumption balance and key technology innovation in China's oil and gas industry are reviewed in the present study, and new strategies and roadmaps are proposed to cope with the challenges. The study found that (i) the oil and gas market faces challenges such as incomplete pricing mechanisms, unclear subject rights, and the lack of recognition and trading of carbon assets. (ii) the trade-off between short-term supply security and long-term low-carbon supply is the most critical issue. (iii) in addition to typical challenges such as immature technology and lack of funding support, the unclear multiple technology coupling development mode also poses problems for the low-carbon transformation of the oil and gas industry. To address these new challenges, comprehensive strategies and roadmaps for China's oil and gas industry towards carbon neutrality are proposed and discussed in the aspects of participating in market transactions, restructuring production and consumption, deploying key technology innovations, and planning enterprise strategies. The present study is expected to provide a blueprint for the future development of China's oil and gas industry towards carbon neutrality.

关键词： China's oil and gas industry Carbon neutrality Challenges and strategies

Segmental nature of the Red River fault revealed by seismic anisotropy and geological structures

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Science China Earth Sciences 2024年第8期67卷 2423-2443页

作者： Ying LI yuan gao School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake AdministrationBeijing 100036China

As the western boundary of the Sichuan-Yunnan block(SYB),the Red River fault(RRF)is a major fault that controls deep crustal movement and deformation in the southeast margin of the Tibetan Plateau and regulates middle-lower crustal *** data suggest that the RRF is segmented and exhibits distinct variations in seismicity,velocity structure and crustal deformation from north to *** anisotropy reveals a complex pattern of lateral spatial and vertical stratified distributions.(1)From the perspective of crustal stratification,in the upper crust,the fast wave polarization in the north segment of the RRF is complex and possibly influenced by the Sanjiang lateral collision zone and adjacent faults with varying *** fast wave polarization in the middle segment is in the NW-SE direction,indicating a localized area of closed down or locked up with consistent *** in the south segment,it presents a disordered pattern,signifying complex deep tectonics and stress conditions at the wedged intersection *** the middle-lower crust in the north and south segments of the RRF,the azimuthal anisotropy is strong and consistent with the spatial strike of the weak zone characterized by low-velocity and *** suggests a connection between the anisotropy and the material migration.(2)In the whole crustal scale,the fast wave directions in two sides of the RRF are consistent with the NW-SE tectonic *** indicates that the RRF,as a large fault potentially cutting through the whole crust,strongly controls the surrounding media.(3)In the lithospheric scale,the fast wave polarizations are oriented nearly E-W and independent of the fault strike,consistent with the low P-and S-wave velocity structures and positive radial anisotropy in the upper *** fast wave directions could be related to lithospheric olivine deformation and asthenospheric *** paper suggests a decoupling of deformation between the crust and the lithospheri

关键词： Red River fault Seismic anisotropy Geological structures Lithosphere Fault segmentation

New Evidence for Improving Omega Estimation by Explicitly Considering Horizontal Divergence

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Advances in Atmospheric Sciences 2014年第2期31卷 449-456页

作者： yuan Zhuojian QI Jindian gao Shouting feng Yerong XU Pengcheng WU Naigeng Center for Monsoon and Regional Environment/Department of Atmospheric Science Sun Yat-sen University Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of Sciences Guangdong Meteorological Observatory Institute of Applied Mathematics Academy of Mathematics and Systems SciencesChinese Academy of Sciences

It is well known that the quasi-geostrophic （QG） omega equation with only two contributors respectively associated with vorticity advection （VA） and temperature advection is derived for midlatitude synoptic-scale systems *** on reliable reanalysis data,new evidence revealed by cyclonic and anticyclonic cases indicates that forecasters might sometimes experience problems by paying too much attention to the 500-hPa VA when estimating vertical motions not only in subtropical systems but also in systems meeting all the assumptions of the QG omega *** investigations also showed that explicitly considering the vertical profiles of horizontal divergence could allow for better interpretation of vertical motions and weather in these real cases,suggesting that this equation might not be sufficient due to the presence of only two horizontaldivergence-related （HDR） mechanisms and the absence of other HDR mechanisms,e.g.,frictional force,mountain barriers,diabatic/adiabatic processes,and acceleration/deceleration of air flows.

关键词： omega estimation weather forecast horizontal divergence vertical motion

Editors' selection of papers from China's academic journals

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National Science Review 2018年第5期5卷 123-125页

作者： gao, yuan

PHYSICS Photonic spin-Hall effect in single catenary nanoholes The photonic spin-Hall effect is an important but intrinsically weak effect at the *** Luo and co-workers from the Institute of Optics and Electronics,Chi... 详细信息

关键词： Editors selection of papers from China’s academic journals CAS

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A closure model on velocity structure functions in homogeneous isotropic turbulence

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Applied Mathematics and Mechanics(English Edition) 2017年第11期38卷 1627-1634页

作者： Le FANG feng gao Laboratory of Mathematics and Physics Ecole Centrale de Pekin Beihang University Beijing 100191 China Co-Innovation Center for Advanced Aero-Engine Beihang University Beijing 100191 China Faculty of Engineering and Physical Sciences University of Surrey Guildford GU2 7XH U. K.

Closure models started from Chou＇s work have been developed for more than 70 years, aiming at providing analytical tools to describe turbulent flows in the spectral space. In this study, a preliminary attempt is presented to introduce a closure model in the physical space, using the velocity structure functions as key parameters. The present closure model appears to qualitatively reproduce the asymptotic scaling behav- iors at small and large scales, despite some inappropriate behaviors such as oscillations. Therefore, further improvements of the present model are expected to provide appropriate descriptions of turbulent flows in the physical space.

关键词： homogeneous isotropic turbulence closure model structure function

FEM Analysis on Acoustic Performance of Wall Flow Diesel Particulate Filters

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Chinese Journal of Mechanical Engineering 2011年第4期24卷 701-706页

作者： gao Wenzhi feng Liming State Key Laboratory of Engines Tianjin University Tianjin 300072 China

Diesel powered vehicles, in compliance with the more strict exhaust emission standards such as Euro V, is likely to require a diesel particulate filter （DPF）. A DPF used on a vehicle will affect the acoustic emission of the diesel engine, so it is important to investigate the sound propagation rule in DPF and further to propose the optimum DPF design. However, due to the geometrical complexity of the DPF, the traditional analysis method, such as analytical method, can not assess the acoustic performance of DPF accurately in medium and high frequency band. In this paper, a combined approach of finite element analysis and viscosity correction is proposed to predict acoustic performance of DPF. A simplified model of the full DPF is established and is used to analyze the sound propagation characteristic of the DPF. The distribution of the sound pressure and velocity, the transmission matrix of the DPF are obtained using the finite element method. In addition, the method of the viscosity correction is used in the transmission matrix of the DPF to evaluate the acoustic performance of DPF. Based on the FEM computation and the viscosity correction, the transmission losses under the rated load and idle condition of a diesel engine are calculated. The calculation results show that DPF can effectively attenuate exhaust noise, and sound attenuation increase with the rise of the frequency. Sound attenuation is better under rated condition than idle condition of diesel engine, particularly in frequency above 1 000 Hz.

关键词： diesel particulate filter acoustic performance FEM model viscosity correction

Synthesis of the fluid machinery network in a circulating water system

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Chinese Journal of Chemical Engineering 2019年第3期27卷 587-597页

作者： Wei gao Xiao feng School of Chemical Engineering and Technology Xi'an Jiaotong University

Energy consumption of the fluid machinery network in a circulating water system takes up a large part of energy consumption in the process industry, so optimization on the network will enhance the economic and environmental performance of the industry. In this paper, a synthesis approach is proposed to obtain the optimal network structure. The effective height curves are used as tools to perform energy analysis, so that the potential placement of water turbines and auxiliary pumps can be determined with energy benefit. Then economic optimization is carried out, by the mathematical model with the total cost as the objective function, to identify the branches for water turbines and auxiliary pumps with economic benefit. In this way, the optimal fluid machinery network structure can be obtained. The results of case study indicate that the proposed synthesis approach to optimize the fluid machinery network will obtain more remarkable benefits on economy, compared to optimizing only the water turbine network or pump network. The results under different flowrates of circulating water reveal that using a water turbine to recover power or adding an auxiliary pump to save energy in branches are only suitable to the flowrate in a certain range.

关键词： Fluid machinery network Synthesis approach Flowrate range Network structure

Type Synthesis of Walking Robot Legs

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 53-65页

作者： Da Xi feng gao State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University

Walking robots use leg structures to overcome obstacles or move on complicated terrains. Most robots of current researches are equipped with legs of simple structure. The specific design method of walking robot legs is seldom studied. Based on the generalized-function(GF) set theory, a systematic type synthesis process of designing robot legs is introduced. The specific mobility of robot legs is analyzed to obtain two main leg types as the goal of *** synthesis problem is decomposed into two stages, actuation and constraint synthesis by name,corresponding to the combinatorics results of linear Diophantine equations. Additional restrictions are discussed to narrow the search range to propose practical limb expressions and kinematic-pair designs. Finally, all the fifty-one leg structures of four subtypes are carried out, some of which are chosen to make up robot prototypes, demonstrating the validity of the method. This paper proposed a novel type synthesis methodology, which could be used to systematically design various practical robot legs and the derived robots.

关键词： Type synthesis Robot leg GF set Number synthesis Linear Diophantine equation