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Determining Pressure with Daughter Minerals in Fluid Inclusion by Raman Spectroscopy:Sphalerite as an Example

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Acta Geologica Sinica(English Edition) 2009年第3期83卷 628-632页

作者： YANG yuping zheng Haifei ZHANG Lifei The Key Laboratory of Orogenic Belts and Crustal Evolution MOE School of Earth and Space Sciences Peking University Beijing 100871 China

Raman frequency of some materials, including minerals, molecules and ions, shifts systematically with changing pressure and temperature. This property is often used as a pressure gauge in high pressure experiments with the hydrothermal diamond anvil cell （HDAC）. Since the system of fluid inclusion is similar to that of HDAC, it can also be used to determine the internal pressure of fluid inclusions. Sphalerite is a common daughter mineral. In this study, the frequency shift of the 350 cm-1 peak of sphalerite has been studied from 296 to 523 K and from 0.07 to 2.00 GPa using the HDAC. The global slope of the isotherms （V350/p）T is 0.0048 in the studied pressure range. No significant variation of the slopes with temperature has been observed. The correlation between the frequency shift of the 350 cm-1 peak of sphalerite and pressure and temperature is constrained as P=208.33（△ Vp）350＋3.13T-943.75. This relationship may be used to estimate the internal pressure of the sphalerite-bearing fluid inclusions.

关键词： pressure fluid inclusion sphalerite Raman

Continuous Commutation Failure Suppression Method Based on Self-adaptive Auto-disturbance Rejection Proportional-integral Controller for HVDC Transmission System

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Journal of Modern Power Systems and Clean Energy 2020年第6期8卷 1178-1187页

作者： Tonghua Wu yuping zheng Qipu Liu Guoqiang Sun Xiaohong Wang Xindong Li the College of Energy and Electrical Engineering Hohai UniversityNanjing 210098China NARI Group Corporation Nanjing 211106China State Key Laboratory of Smart Grid Protection and Control Nanjing 211106China

Once an asymmetrical fault occurs on the AC side of the receiving-end of a high-voltage direct current(HVDC)transmission system,the current reference will be affected by the control regulation on the DC inverter side and the commutation voltage *** this case,the advance firing angle will fluctuate periodically,causing security threats to the *** the fault cannot be cleared in time,the effect may be even more ***,the traditional proportional-integral(PI)controller cannot effectively suppress the periodic components in the input error signal,which is an important cause of continuous commutation ***,the system requires more time to recover from the *** by this,a selfadaptive auto-disturbance rejection PI controller is proposed in this *** controller has the advantages of fast response speed and strong anti-interference ability of the auto-disturbance rejection *** one hand,it can automatically adjust PI,and the parameters can maintain the system’s adaptive *** the other hand,the discretization process satisfies the computer simulation *** applying the proposed controller to a system under constant current control and extinction angle control,the dynamic response speed can be improved and the robust performance of the system can be ensured when dealing with a wide range of ***,simulation results show that the proposed algorithm can effectively suppress the continuous commutation failure of DC transmission systems.

关键词： High-voltage direct current(HVDC)transmission continuous commutation failure periodic fluctuation self-adaptive auto-disturbance rejection proportional-integral(PI)controller computer simulation

Transmission Line Distance Protection Under Current Transformer Saturation

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Journal of Modern Power Systems and Clean Energy 2021年第1期9卷 68-76页

作者： yuping zheng Tonghua Wu Feng Hong Gang Yao Jimin Chai Zhinong Wei the College of Energy and Electrical Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Smart Grid Protection and Control NARI Group CorporationNanjing 211106China Changzhou Institute of Technology Changzhou 213032China

Conventional transmission line distance protection approaches are subject to malfunction under reverse fault-induced current transformer(CT) saturation for the typically employed breaker-and-a-half configuration. This paper addresses this issue by proposing a new distance protection approach that combines the blocking and unblocking criteria of distance protection based on the values of incomplete differential current,operation voltage, and current harmonic content. The proposed approach is verified by theoretical analysis, dynamic simulation testing, and field operation to ensure that the obtained distance protection is reliable and refrains from operating unnecessarily under reverse fault-induced CT saturation in the breaker-and-ahalf configuration. Meanwhile, the proposed approach is demonstrated can operate reliably when forward faults occur or various reverse faults are converted to forward faults.

关键词： Breaker-and-a-half configuration current transformer(CT)saturation distance protection power frequency variation operation voltage

Research on DC Protection Strategy in Multi-Terminal Hybrid HVDC System

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Engineering 2021年第8期7卷 1064-1075页

作者： yuping zheng Jiawei He Bin Li Tonghua Wua Wei Dai Ye Li State Key Laboratory of Smart Grid Protection and Control State Grid Electric Power Research Institute(NARI Group Corporation)Nanjing 211106China Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjin 300072China College of Energy and Electrical Engineering Hohai UniversityNanjing 210098China

Multi-terminal hybrid high-voltage direct current(HVDC)systems have been developed quickly in recent years in power transmission ***,for voltage-source converter(VSC)stations in hybrid HVDC systems,no direct current(DC)filters are *** addition,the DC reactor is also not installed at the line end because the DC fault can be limited by the converter *** means that the boundary element at the line end is absent,and the single-ended protections used in line commutated converter(LCC)based HVDC(LCC-HVDC)systems or VSC-HVDC systems cannot distinguish the fault line in multi-terminal hybrid HVDC *** paper proposes a novel singleended DC protection strategy suitable for the multi-terminal hybrid HVDC system,which mainly applies the transient information and active injection concept to detect and distinguish the fault *** with the single-ended protections used in LCC-HVDC and VSC-HVDC systems,the proposed protection strategy is not dependent on the line boundary element and is thus suitable for the multiterminal hybrid HVDC *** corresponding simulation cases based on power systems computer aided design(PSCAD)/electromagnetic transients including DC(EMTDC)are carried out to verify the superiority of the proposed protection.

关键词： Multi-terminal hybrid HVDC system Single-ended protection Transient information Active injection

新疆中天山北坡断裂带不同海拔高度土壤温度分布特征

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维普期刊数据库

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中国农学通报 2024年第6期40卷 84-90页

作者：宫恒瑞郑玉萍苗运玲乌鲁木齐市气象局乌鲁木齐830002

研究中天山断裂带从高山带到准噶尔盆地边缘整个过渡带的土壤温度分布特征有助于理解干旱区土壤环境特征,从而为土地利用、农业生产提供依据。本文选取新疆中天山断裂带海拔高度呈梯度分布的6个气象站2005年至2020年各层土壤温度的日观... 详细信息

研究中天山断裂带从高山带到准噶尔盆地边缘整个过渡带的土壤温度分布特征有助于理解干旱区土壤环境特征,从而为土地利用、农业生产提供依据。本文选取新疆中天山断裂带海拔高度呈梯度分布的6个气象站2005年至2020年各层土壤温度的日观测数据,利用统计方法分析了不同地形、不同深度土壤温度随海拔高度的变化特征以及不同海拔高度土壤温度随深度的变化特征。分析表明:中天山北坡土壤温度变幅随海拔高度的降低而升高。不同地形的土壤最高温和最低温的年温差浅层大于深层,由浅至深年最高温度和年最低温度出现的时间逐渐推迟;年内中天山北坡不同海拔高度0~20 cm的土壤日平均温度曲线大致呈余弦函数曲线,320 cm深度的土壤温度基本呈正弦函数分布,较0~20 cm地温的最高和最低晚3个月左右。研究区土壤温度随海拔高度降低呈现先升高后降低的趋势。在海拔为3539~600 m高度范围,土壤温度随着海拔的升高而降低。在600~441 m高度范围,土壤温度随着海拔的下降而下降;0~20 cm为土壤温度变化的活跃层,40 cm深度的土壤温度可称之为过渡层,320 cm深度称为土壤温度的稳定层,80~160 cm称为土壤温度的次稳定层。

关键词：中天山北坡海拔高度土壤温度分布特征

不同水生植物对富营养化水体净化和温室气体排放的影响

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环境污染与防治 2024年第5期46卷 618-625页

作者：杨科刘丽香韩永伟邓淏丹郑玉萍张恩祥中国环境科学研究院北京100012 兰州大学生命科学学院甘肃兰州730000

水体富营养化和温室效应均是目前较为严重的环境问题。已有的水生植物净化富营养化水体研究主要侧重于净化效果,较少研究其净化过程中温室气体的排放特征,更忽略了水生植物对富营养化水体的减污降碳协同治理效果。基于此,通过人为添加... 详细信息

水体富营养化和温室效应均是目前较为严重的环境问题。已有的水生植物净化富营养化水体研究主要侧重于净化效果,较少研究其净化过程中温室气体的排放特征,更忽略了水生植物对富营养化水体的减污降碳协同治理效果。基于此,通过人为添加氮磷模拟富营养化水体,将水生植物——水竹(Phyllostachys heteroclada Oliver)、竹叶眼子菜(Potamogeton wrightii Morong)、黑藻(Hydrilla verticillate(L.F.)Royle)、铜钱草(Hydrocotyle vulgaris L)、纸莎草(Cyperus papyrus Linn)和黄花水龙(Ludwigia peploides ***(Ohwi)Raven)设置5个试验组及1个空白组,研究不同水生植物及其组合对富营养化水体的净化效果和温室气体(CO_(2)、CH_(4)、N_(2)O)排放特征。结果表明:1)在富营养化水体净化过程中,各试验组在净化第15天基本上能把水体净化完全。2)净化第15天时,水-气界面CO_(2)、CH_(4)、N_(2)O净排放通量以及全球增温潜势(GWP)最低的试验组均是铜钱草单种,分别是-44.09、0.07、0.49 mg/(m^(2)·h)与38906.89 mg/m^(2)。研究显示,在选择水生植物净化富营养化水体时,铜钱草单种能较好实现减污降碳协同治理。

关键词：温室气体水生植物富营养净化

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基于相火理论辨治雄激素性脱发

现代中医临床 2024年第4期31卷 91-94页

作者：黄清瑞郑屿萍张彦峰何翔三明市皮肤病医院三明365000 上海中医药大学附属曙光医院

雄激素性脱发(androgenetic alopecia, AGA)是最常见的脱发类型,中医学称其为“发蛀脱发”“蛀发癣”。相火理论是中医学的特色理论之一,对临床诊治疾病有重要的指导意义。生理性相火是维持人体生命活动的原动力,相火妄动即病理性相火,... 详细信息

雄激素性脱发(androgenetic alopecia, AGA)是最常见的脱发类型,中医学称其为“发蛀脱发”“蛀发癣”。相火理论是中医学的特色理论之一,对临床诊治疾病有重要的指导意义。生理性相火是维持人体生命活动的原动力,相火妄动即病理性相火,是导致疾病的贼邪,其成因主要为脏腑之火相煽、情志失调。AGA根本病机为相火妄动,主要表现在:情志过极,相火亢盛;劳欲不节,相火离位;禀赋异常,相火易亢。基于相火理论治疗AGA,包括:养心正志,相火自安;安宁君火,清降相火;滋阴固本,补水泻火;阴阳双补,引火归元。本文结合临床验案阐述基于相火理论对AGA的辨治。

关键词：相火相火妄动雄激素性脱发脱发

Fast Distance Protection Scheme for Wind Farm Transmission Lines Considering R-L and Bergeron Models

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Journal of Modern Power Systems and Clean Energy 2023年第3期11卷 840-852页

作者： Zepeng Hu Bin Li yuping zheng Tonghua Wu Jiawei He Bin Yao Yaru Sheng Wei Dai Xindong Li Electrical Engineering and Automation Tianjin UniversityTianjinChina State Key Laboratory of Smart Grid Protection and Control NARI Group CorporationNanjingChina

The distributed capacitance of the line becomes larger as the scale of wind farms,the transmission voltage level,and the transmission distance ***,the error of the traditional time-domain distance protection scheme based on the R-L model,which ignores the distributed capacitance of the line,becomes ***,the error of the time-domain fault location method based on the R-L model,especially the maximum error range,is theoretically analyzed in this *** this basis,a novel fault location method based on the RL and Bergeron models is ***,a fast time-domain distance protection scheme is *** the proposed scheme,the error in the fitting calculation is used to construct a weight matrix,and an algorithm for solving the time-domain differential equations is designed to improve the calculation speed and *** with the traditional frequency-domain distance protection scheme,the proposed scheme is independent of the power supply characteristics;thus,it is suitable for wind farm transmission *** addition,compared with the traditional method based on the R-L model,the proposed scheme effectively avoids the negative influence of the distributed capacitance of the line,which significantly improves the operating *** types of faults are simulated by PSCAD/EMTDC to verify the effectiveness and superiority of the proposed scheme.

关键词： Transmission line R-L model time-domain distance protection wind farm

Determination of inner pressure for fluid inclusions by Raman spectroscopy and its application

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Geoscience Frontiers 2011年第3期2卷 403-407页

作者： Haifei zheng Erwei Qiao yuping Yang Tiyu Duan Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China

Using a Diamond Anvil Cell combined with micro Raman spectroscopy, the quantitative relations among Raman shifts, pressure and temperature were obtained for the vibration of O-H in H2O-NaCl, C-O in CO3^2-, S-O in SO4^2- and C-H in n-heptane-cyclohexane. Based on the quantitative relationships obtained, it is possible to determine the inner pressure for single fluid inclusions and to further determine the isochore of the systems. It is not only helpful to obtain the forming temperatures and pressures of the enclosing minerals, but also to be able to provide information concerning the chemical compositions of the fluid inclusions.

关键词： Raman spectroscopy Fluid inclusion Inner pressure Isochore line Forming temperature andpressure of minerals