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Differences of tuffaceous components dissolution and their impact on physical properties in sandstone reservoirs: A case study on Paleogene Wenchang Formation in Huizhou-Lufeng area, Zhu I Depression, Pearl River Mouth Basin, China
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作者 JIN Zihao YUAN Guanghui +4 位作者 ZHANG Xiangtao CAO Yingchang DING Lin LI Xiaoyan FU Xiaohan 《Petroleum Exploration and Development》 2023年第1期111-124,共14页
The element geochemical characteristics and diagenetic alteration products of tuffaceous components in sandstone reservoirs of Paleogene Wenchang Formation in typical subsags of the Huizhou-Lufeng area of the Zhu I De... The element geochemical characteristics and diagenetic alteration products of tuffaceous components in sandstone reservoirs of Paleogene Wenchang Formation in typical subsags of the Huizhou-Lufeng area of the Zhu I Depression,Pearl River Mouth Basin,were identified through microscopic analysis and quantitative analysis of main and trace elements.The impacts of dissolution of different tuffaceous components on physical properties of reservoirs were discussed through quantitative characterization of reservoir physical properties.The results show that there are mainly four types of tuffaceous components in the study area,which are acidic,intermediate,basic and alkaline tuffaceous components.The acidic tuffaceous components evolved in a process of strong alteration and weak dissolution of alteration products,with a large amount of kaolinite precipitated during alteration to disenable the improvement of porosity and permeability.The intermediate and alkaline tuffaceous components evolved in a process of strong dissolution of tuffaceous components and strong alteration of residual tuffaceous components;the dissolution of tuffaceous components created intergranular pores,but the alteration products such as autogenic quartz,apatite and illite deteriorated the pore structure;ultimately,the dissolution of tuffaceous components resulted in the increase of porosity but no increase of permeability of the reservoir.The basic tuffaceous components dominantly evolved in a process of dissolution of tuffaceous components to strong dissolution of alteration products;both tuffaceous components between particles and laumontite generated from alteration can be strongly dissolved to create pores;thus,the dissolution of tuffaceous components can significantly increase the physical properties of the reservoir. 展开更多
关键词 Zhu I Depression Huizhou Sag Lufeng Sag tuffaceous component DISSOLUTION physical property response Paleogene Wenchang Formation
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The Impact of Big Five Personality Traits on Older Europeans’ Physical Health
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作者 Eleni Serafetinidou Christina Parpoula 《Journal of Biomedical Science and Engineering》 2024年第2期41-56,共16页
Investigating the role of Big Five personality traits in relation to various health outcomes has been extensively studied. The impact of “Big Five” on physical health is here explored for older Europeans with a focu... Investigating the role of Big Five personality traits in relation to various health outcomes has been extensively studied. The impact of “Big Five” on physical health is here explored for older Europeans with a focus on examining age groups differences. The study sample included 378,500 respondents derived from the seventh data wave of Survey of Health, Aging and Retirement in Europe (SHARE). The physical health status of older Europeans was estimated by constructing an index considering the combined effect of well-established health indicators such as the number of chronic diseases, mobility limitations, limitations with basic and instrumental activities of daily living, and self-perceived health. This index was used for an overall physical health assessment, for which the higher the score for an individual, the worst health level. Then, through a dichotomization process applied to the retrieved Principal Component Analysis scores, a two-group discrimination (good or bad health status) of SHARE participants was obtained as regards their physical health condition, allowing for further con-structing logistic regression models to assess the predictive significance of “Big Five” and their protective role for physical health. Results showed that neuroti-cism was the most significant predictor of physical health for all age groups un-der consideration, while extraversion, agreeableness and openness were not found to significantly affect the self-reported physical health levels of midlife adults aged 50 up to 64. Older adults aged 65 up to 79 were more prone to open-ness, whereas the oldest old individuals aged 80 up to 105 were mainly affected by openness and conscientiousness. . 展开更多
关键词 Big Five Personality Traits physical Health Older Europeans SHARE Principal component Analysis
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Dissociation of polar oil components in low salinity water and its impact on crude oil-brine interfacial interactions and physical properties 被引量:2
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作者 Rasoul Mokhtari Shahab Ayatollahi 《Petroleum Science》 SCIE CAS CSCD 2019年第2期328-343,共16页
Despite many efforts into the study of fluids interaction in low salinity water flooding, they are not probing the basics of transport phenomena between the involved phases. This work is aimed to bring new understandi... Despite many efforts into the study of fluids interaction in low salinity water flooding, they are not probing the basics of transport phenomena between the involved phases. This work is aimed to bring new understanding of fluid-fluid interaction during low salinity water flooding through a series of organized experiments in which a crude oil sample with known properties was kept in contact with different brine solutions of various ionic strengths. Measuring brine pH, conductivity and crude oil viscosity and density for a period of 45 days illustrates the strong effect of the contact time and ionic strength on the dissociation of polar components and physical properties of the crude oil and brine. Besides, the interfacial tension(IFT) measurements show that the interfacial interactions are affected by several competitive interfacial processes. By decreasing the ionic strength of the brine, the solubility of naphthenic acids in the aqueous solution increases, and hence,the conductivity and the pH of the aqueous phase decrease. To verify this important finding, UV-Vis spectroscopy and 'H NMR analysis were also performed on aged brine samples. Notably, there is an ionic strength of brine in which the lowest IFT is observed, while the other physical properties are remained relatively unchanged. 展开更多
关键词 Ionic strength Oil-brine interaction physical properties Contact time POLAR components
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Correlation Analysis of Processing Technology,Physical Parameters and Chemical Components during Plain Stir-baking of Trichosanthis Radix
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作者 Xinhong ZHAO Ruiying LI +3 位作者 Chao SUN Zhenhua LIU Xu XIAO Tianchao CHEN 《Medicinal Plant》 CAS 2021年第5期51-55,59,共6页
[Objectives]To explore the correlation of processing technology,physical parameters and chemical components during plain stir-baking of Trichosanthis Radix.[Methods]Based on mixture uniform experiment design,the Trich... [Objectives]To explore the correlation of processing technology,physical parameters and chemical components during plain stir-baking of Trichosanthis Radix.[Methods]Based on mixture uniform experiment design,the Trichosanthis Radix was prepared by plain stir-bake method.Delphi method was used to evaluate and select the highest-scoring processed product for measuring physical parameters.UV spectrophotometry was used to determine the contents of starch and polysaccharide.The correlation and linear regression model of processing technology,physical parameters and chemical components were established with the aid of SPSS 26.0[Results]After processing by plain stir-bake method,the relative density and chromaticity showed a decreasing trend in the processed products of Trichosanthis Radix,the oxidation value,hydroscopic rate and swelling decreased firstly and then increased,and pH increased firstly and then decreased.The content of total starch decreased,the content of polysaccharide increased,and there was a negative correlation between them.There was a significant positive correlation between temperature and oxidation value,swelling and hydroscopic rate,hydroscopic rate and polysaccharide,and there was a significant negative correlation between relative density and hydroscopic rate or polysaccharide,total starch and hydroscopic rate or swelling.The linear relation model between processing technology and physical parameters and chemical components was r2>0.9.[Conclusions]After processing by plain stir-bake method,the physical parameters of Trichosanthis Radix changed,and there may be mutual conversion between total starch and polysaccharides.To a certain extent,physical parameters can be used to evaluate the quality of processed products of Trichosanthis Radix.This study is expected to provide a reference for research on quality evaluation of processed products of traditional Chinese medicine. 展开更多
关键词 Trichosanthis Radix Processing technology physical parameters Chemical components CORRELATION
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A study on the multi-componentsubstrom current
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作者 徐文耀 孙伟 《Chinese Journal of Polar Science》 2000年第1期53-58,共6页
A new technique of eigen mode analysis, Method of Natural Orthogonal Components (MNOC) is used to analyze the ionospheric equivalent current systems obtained on the basis of magnetic data at six meridian magnetometer ... A new technique of eigen mode analysis, Method of Natural Orthogonal Components (MNOC) is used to analyze the ionospheric equivalent current systems obtained on the basis of magnetic data at six meridian magnetometer chains in the northern hemisphere during March 17 19, 1978. The results show that the whole current pattern for any given instant consists of a few eigen modes with different intensities. The first eigen mode exhibits a two cell current construction, characterizing the large scale magnetospheric convection and directly driven process, while the second eigen mode shows a concentrated westward electrojet at midnight sector, characterizing the substorm current wedge and the loading unloading process. The first mode consistently exists whenever during quiet periods or at substorms, and its intensity increases from the beginning of the growth phase of substorms, then quickly intensifies in the expansion phase, followed by a gradual decrease in the recovery phase. On the other hand, the intensity of the second mode remains to be near zero during both quiet time and the growth phase of substorms. Its rapid enhancement occurs in the expansion phase. These characteristics in the current patterns and the intensity variations coincide with the defined physical processes of the directly driven and loading unloading components. 展开更多
关键词 SUBSTORM equivalent current system method of natural orthogonal components (MNOC).
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The Current Situation and Improvement Strategy of Physical Education in Colleges and Universities
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作者 Chengbin Huang 《Journal of Contemporary Educational Research》 2021年第4期1-4,共4页
At present,physical education is listed as the key teaching.This paper introduces the importance of physical education in Colleges and universities,analyzes the current situation of College Physical Education and expl... At present,physical education is listed as the key teaching.This paper introduces the importance of physical education in Colleges and universities,analyzes the current situation of College Physical Education and explores the improvement strategies of College Physical Education at this stage. 展开更多
关键词 College physical education physical education teaching The current teaching situation Improvement strategy
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Numerical methods for the magneto-mechanical coupling analysis of invessel components in Tokamak devices 被引量:1
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作者 Xudong Li Shejuan Xie +1 位作者 Cuixiang Pei Zhenmao Chen 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第3期173-179,共7页
Magneto-mechanical coupling vibration arises in the in-vessel components of Tokamak devices especially during the plasma disruption. Strong electromagnetic forces cause the structures to vibrate while the motion in tu... Magneto-mechanical coupling vibration arises in the in-vessel components of Tokamak devices especially during the plasma disruption. Strong electromagnetic forces cause the structures to vibrate while the motion in turn changes the distribution of the electromagnetic field. To ensure the Tokamak devices operating in a designed state, numerical analysis on the coupling vibration is of great importance. This paper introduces two numerical methods for the magneto-mechanical coupling problems. The coupling term of velocity and magnetic flux density is manipulated in both Eulerian and Lagrangian description, which brings much simplification in numerical implementation. Corresponding numerical codes have been developed and applied to the dynamic simulation of a test module in J-TEXT and the vacuum vessel of HL-2M during plasma disruptions. The results reveal the evident influence of the magnetic stiffness and magnetic damping effects on the vibration behavior of the in-vessel structures. Finally, to deal with the halo current injection problem, a numerical scheme is described and validated which can simulate the distribution of the halo current without complicated manipulations. 展开更多
关键词 Magneto-mechanical coupling analysis In-vessel component Plasma DISRUPTION HALO current NUMERICAL simulation
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Experimental and analytical investigation on metal damage suffered from simulated lightning currents 被引量:3
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作者 刘亚坤 傅正财 +2 位作者 刘全桢 刘宝全 Anirban GUHA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第12期33-41,共9页
The damage of two typical metal materials, Al alloy 3003 and steel alloy Q235 B, subjected to four representative lightning current components are investigated by laboratory and analytical studies to provide fundament... The damage of two typical metal materials, Al alloy 3003 and steel alloy Q235 B, subjected to four representative lightning current components are investigated by laboratory and analytical studies to provide fundamental data for lightning protection. The four lightning components simulating the natural lightning consist of the first return stroke, the continuing current of interval stroke, the long continuing current, and the subsequent stroke, with amplitudes 200 k A, 8 k A,400 A, and 100 k A, respectively. The damage depth and area suffered from different lightning components are measured by the ultrasonic scanning system. And the temperature rise is measured by the thermal imaging camera. The results show that, for both Al 3003 and steel Q235 B, the first return stroke component results in the largest damage area with damage depth0.02 mm uttermost. The long continuing current component leads to the deepest damage depth of 3.3 mm for Al 3003 and much higher temperature rise than other components. The correlation analysis between damage results and lightning parameters indicates that the damage depth has a positive correlation with charge transfer. The damage area is mainly determined by the current amplitude and the temperature rise increases linearly with the charge transfer larger. 展开更多
关键词 metal damage lightning currents different components temperature rise
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Part 2: Review of Tokamak Physics as a Way to Construct a Device Optimal for Graviton Detection and Generation within a Confined Small Spatial Volume, as Opposed to Dyson’s “Infinite Astrophysical Volume” Calculations 被引量:2
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第1期138-155,共18页
Review of arguments in refutation of Dyson’s alleged prohibition against use of device physics as to determining if Gravitons can be determined to exist is followed up by use of a hot Plasma within a Tokamak in a red... Review of arguments in refutation of Dyson’s alleged prohibition against use of device physics as to determining if Gravitons can be determined to exist is followed up by use of a hot Plasma within a Tokamak in a redo of the amplitude of alleged Gravitational waves. This overlaps with gravitons, and we follow up with an analysis of the pertinent form of Gravitons, i.e. do we have massless or massive gravitons. In addition we also obtain GW of amplitude as low as five meters above the Tokamak center such low strain values are extremely close to brane world GW, and strain values in early universe cosmology. This is after our device analysis. Using Grischuk and Sachin (1975) amplitude for the GW generation due to plasma in a toroid, we generalize this result for Tokamak physics. We obtain evidence for strain values up to?in a Tokamak center. These values are an order of magnitude sufficient to allow for possible detection of gravitational waves. The critical breakthrough is in utilizing a burning plasma drift current, which relies upon a thermal contribution to an electric field. Such low strain values are extremely close to brane world GW, and strain values in early universe cosmology. We conclude with statements as to comparing our basic results with those of Yan-Gang Miao, Ying-Jie Zhao as to their generalized HUP which gives support to the suppositions given in our comparison of the character of gravitons which are initially at the start of inflation versus those of our present era, as measured by the Tokamak. 展开更多
关键词 TOKAMAK physicS Confinement Time (of Plasma) GW Amplitude Drift current
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A review of current research on spin currents and spin–orbit torques
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作者 冯晓玉 张琪涵 +5 位作者 张瀚文 张祎 钟瑞 卢博文 曹江伟 范小龙 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期121-152,共32页
Spintronics is a new discipline focusing on the research and application of electronic spin properties. After the discovery of the giant magnetoresistance effect in 1988, spintronics has had a huge impact on scientifi... Spintronics is a new discipline focusing on the research and application of electronic spin properties. After the discovery of the giant magnetoresistance effect in 1988, spintronics has had a huge impact on scientific progress and related applications in the development of information technology. In recent decades, the main motivation in spintronics has been efficiently controlling local magnetization using electron flow or voltage rather than controlling the electron flow using magnetization. Using spin-orbit coupling in a material can convert a charge current into a pure spin current(a flow of spin momenta without a charge flow) and generate a spin-orbit torque on the adjacent ferromagnets. The ability of spintronic devices to utilize spin-orbit torques to manipulate the magnetization has resulted in large-scale developments such as magnetic random-access memories and has boosted the spintronic research area. Here in, we review the theoretical and experimental results that have established this subfield of spintronics. We introduce the concept of a pure spin current and spin-orbit torques within the experimental framework, and we review transport-, magnetization-dynamics-, and opticalbased measurements and link then to both phenomenological and microscopic theories of the effect. The focus is on the related progress reported from Chinese universities and institutes, and we specifically highlight the contributions made by Chinese researchers. 展开更多
关键词 SPIN-ORBIT coupling PURE SPIN current SPIN-ORBIT TORQUES physical effects associated with SPIN current
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SYSTEMATIC STUDY OF PHYSICAL AND MECHANICAL PROPERTIES OF IMPORTANT CHINESE WOODS
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作者 Dong Yuku Zhao Chunrui Northeast Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1991年第1期83-90,共8页
In this paper,the physical and mechanical properties of important Chinese woodswere studied by using the methods of variable analysis, regression analysis,correlation analysis,principle component analysis and so on sy... In this paper,the physical and mechanical properties of important Chinese woodswere studied by using the methods of variable analysis, regression analysis,correlation analysis,principle component analysis and so on systematically.The results showed synthetical characteristicof the physical and mechanical properties of Chinese woods.Some opinions of former authors wererevised and some new laws were discovered.That is helpful to study of the physical and mechanicalproperties of woods. 展开更多
关键词 physical PROPERTY of WOOD Mechanical PROPERTY of WOOD VARIABLE ANALYSIS Correlation ANALYSIS Principal component ANALYSIS
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Effect of Distortion Ratio on Local Scour Under Tidal Currents and Waves
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作者 窦希萍 董凤舞 《海洋工程:英文版》 EI 2004年第4期613-627,共15页
Five generalized physical models of different distortion ratios were built according to DOU Guo-ren's similarity theory of total sediment transport modeling for estuarine and coastal regions. Experiments on local ... Five generalized physical models of different distortion ratios were built according to DOU Guo-ren's similarity theory of total sediment transport modeling for estuarine and coastal regions. Experiments on local scour in front of groins were made under the actions of tidal currents and waves with clear and sediment entraining water. The scour depths under different dynamic actions are compared. The effect of the distortion ratio on the depth of scour hole is discussed. A relationship between scour depths for distorted and undistorted models is given. 展开更多
关键词 physical model distortion ratio tidal currents WAVES local scour
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Effects of Spatial Information of Soil Physical Properties on Hydrological Modeling Based on a Distributed Hydrological Model
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作者 LI Xianghu ZHANG Qi YE Xuchun 《Chinese Geographical Science》 SCIE CSCD 2013年第2期182-193,共12页
The spatial distribution of soil physical properties is essential for modeling and understanding hydrological processes. In this study, the different spatial information (the conventional soil types map-based spatial ... The spatial distribution of soil physical properties is essential for modeling and understanding hydrological processes. In this study, the different spatial information (the conventional soil types map-based spatial information (STMB) versus refined spatial information map (RSIM)) of soil physical properties, including field capacity, soil porosity and saturated hydraulic conductivity are used respectively as input data for Water Flow Model for Lake Catchment (WATLAC) to determine their effectiveness in simulating hydrological processes and to expound the effects on model performance in terms of estimating groundwater recharge, soil evaporation, runoff generation as well as partitioning of surface and subsurface water flow. The results show that: 1) the simulated stream flow hydrographs based on the STMB and RSIM soil data reproduce the observed hydrographs well. There is no significant increase in model accuracy as more precise soil physical properties information being used, but WATLAC model using the RSIM soil data could predict more runoff volume and reduce the relative runoff depth errors; 2) the groundwater recharges have a consistent trend for both cases, while the STMB soil data tend to produce higher groundwater recharges than the RSIM soil data. In addition, the spatial distribution of annual groundwater recharge is significantly affected by the spatial distribution of soil physical properties; 3) the soil evaporation simulated using the STMB and RSIM soil data are similar to each other, and the spatial distribution patterns are also insensitive to the spatial information of soil physical properties; and 4) although the different spatial information of soil physical properties does not cause apparent difference in overall stream flow, the partitioning of surface and subsurface water flow is distinct. The implications of this study are that the refined spatial information of soil physical properties does not necessarily contribute to a more accurate prediction of stream flow, and the selection of appropriate soil physical property data needs to consider the scale of watersheds and the level of accuracy required. 展开更多
关键词 分布式水文模型 土壤物理性质 空间信息 建模 空间分布格局 地下水补给 水文过程 土壤蒸发
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花岗质岩石中黑云母成分区域性变化对深部物质示踪及成矿的约束:以秦岭地区为例 被引量:1
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作者 王晓霞 王涛 +2 位作者 陈小丹 柯昌辉 杨阳 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第3期811-826,共16页
秦岭造山带早中生代花岗质岩浆及成矿作用非常发育,是探讨地壳深部物质组成及成矿关系的重要地区之一,学者已从岩石学、矿床学和地球化学等角度开展了众多研究,但对成矿作用与花岗岩和地壳深部物质组成的认识仍不太清楚。黑云母是中酸... 秦岭造山带早中生代花岗质岩浆及成矿作用非常发育,是探讨地壳深部物质组成及成矿关系的重要地区之一,学者已从岩石学、矿床学和地球化学等角度开展了众多研究,但对成矿作用与花岗岩和地壳深部物质组成的认识仍不太清楚。黑云母是中酸性岩中常见的暗色矿物,也是指示成矿可能性的重要矿物之一。因此,本文对秦岭该期花岗质岩石中黑云母成分开展研究,为解决该问题探索新途径。对秦岭早中生代花岗质岩石中黑云母成分的研究结果显示,北秦岭和南秦岭两个构造单元中黑云母成分和形成物理条件存在系统差异,揭示其岩浆物源有别,进而制约了其成矿种类特征。北秦岭早中生代花岗质岩石中黑云母的成分和形成条件变化范围小,以MgO(8%~13%)、TiO_(2)(3%~5%)和Cl(0.02%~0.6%)含量较高,F(0.2%~0.4%)含量较低,以及较高的氧逸度(log f O_(2)值为-16.96~-14.62)和温度(682~771℃)为特征;而南秦岭的成分和形成条件总体变化范围较大,具有MgO(3%~15%)、TiO_(2)(2%~4.5%)、Cl(0.01%~0.18%)含量较低,F(0.1%~1.6%)含量较高,以及较低的氧逸度(log f O_(2)值为-20.88~-15.08)和温度(536~754℃)。此外,研究还显示,黑云母的形成压力与岩浆演化程度和矿物组合相关,当岩石中出现黑云母+白云母±石榴子石组合时,压力较高。秦岭两个构造单元中黑云母成分和形成条件的差异,特别是氧逸度和Cl含量的明显不同,揭示各自的成矿种类和成矿潜力不同,如北秦岭较高的氧逸度和Cl含量,形成铜矿的潜力比南秦岭大。同时,两个构造单元中黑云母的成分差异,还揭示了岩浆物源及深部物质组成的不同,即北秦岭比南秦岭具有更为年轻的地壳,这与区域同位素填图示踪的深部物质组成差异基本一致。由此可见,对区域上同时代花岗质岩石中黑云母成分的研究,不仅可以揭示岩浆演化、岩浆结晶过程物理化学条件等,还可示踪深部物质组成的空间变化与差异及成矿种类和潜力,有望成为探测深部物质组成的新方法和了解区域成矿背景和潜力的新途径。 展开更多
关键词 黑云母成分 物理化学条件 花岗质岩石 成矿作用 地壳深部物质
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不同冷冻-解冻处理方式对猕猴桃品质的影响 被引量:1
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作者 李国龙 汪高玮 +2 位作者 岳田利 王周利 赵旭博 《西北农业学报》 CAS CSCD 北大核心 2024年第1期90-98,共9页
以‘徐香’猕猴桃为原材料,系统探究不同冷冻温度(-20℃、-40℃、-50℃和-80℃)及解冻温度(4℃、15℃、25℃和35℃)组合对猕猴桃主要理化性质及香气成分的影响。结果表明:不同冷冻-解冻处理不会影响猕猴桃的色度;与鲜切猕猴桃一致,4℃/... 以‘徐香’猕猴桃为原材料,系统探究不同冷冻温度(-20℃、-40℃、-50℃和-80℃)及解冻温度(4℃、15℃、25℃和35℃)组合对猕猴桃主要理化性质及香气成分的影响。结果表明:不同冷冻-解冻处理不会影响猕猴桃的色度;与鲜切猕猴桃一致,4℃/-50℃、4℃/-80℃和15℃/-80℃处理条件下猕猴桃的可溶性固形物含量均为16.0oBrix。鲜切猕猴桃的可滴定酸和维生素C含量分别为1.22g/hg和45.30 mg/hg,处理后猕猴桃的可滴定酸含量为1.06~1.33g/hg,维生素C含量降低17.62%~33.89%。不同处理后猕猴桃的多酚类物质损失率为20.44%~31.72%,且不同组合处理之间无显著差异。同时,不同处理对猕猴桃香气成分的种类和含量有一定损失,且较低的冷冻温度和解冻温度有利于香气成分的保持。综合考虑,-50℃/4℃和-80℃/4℃冷冻-解冻组合方式可有效保持猕猴桃的品质,为猕猴桃的贮藏保鲜提供了技术支撑。 展开更多
关键词 冷冻 解冻 猕猴桃 理化性质 香气成分
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考虑铁心结构的三相变压器励磁涌流和角型绕组环流分析
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作者 柴济民 郑玉平 潘书燕 《电力科学与技术学报》 CAS CSCD 北大核心 2024年第2期91-100,共10页
基于三相组式、五柱式和三柱式铁心结构变压器的磁路特征和运行方程,首先,提出运用星形侧零序电流和电压来拟合角型绕组环流的数值方法,并进一步研究不同铁心结构变压器的角型绕组环流和励磁涌流的特点;然后,进行软件仿真和现场录波以... 基于三相组式、五柱式和三柱式铁心结构变压器的磁路特征和运行方程,首先,提出运用星形侧零序电流和电压来拟合角型绕组环流的数值方法,并进一步研究不同铁心结构变压器的角型绕组环流和励磁涌流的特点;然后,进行软件仿真和现场录波以验证该数值方法的有效性,可判断三相组式和五柱式变压器的各相绕组差流即为对应相的励磁涌流,而三柱式变压器某相的绕组差流并不是对应相的励磁电流;最后,进一步的理论分析与仿真验证表明,在3类铁心结构的变压器从星形侧空载合闸时,星形侧任意两相的线电流之差可以认为是这两相等效磁路的励磁涌流之差。研究结论可以为不同铁心结构三相变压器的励磁涌流识别提供依据。 展开更多
关键词 变压器 励磁涌流 环流 零序分量
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戈壁集料混凝土物理性能及抗压强度研究
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作者 李超 李建文 +2 位作者 麦麦提明·图尔迪麦麦提 廖浩宇 陈宗平 《混凝土》 CAS 北大核心 2024年第1期101-106,共6页
为资源化利用西北地区工程建设开挖的弃方材料——戈壁集料,基于西北某机场扩建工程的戈壁集料,首先对戈壁集料基本物理性能及矿物成分进行分析,随后以水灰比、戈壁砂率、戈壁细集料种类及水泥浆量为变化参数,先后对戈壁集料混凝土的工... 为资源化利用西北地区工程建设开挖的弃方材料——戈壁集料,基于西北某机场扩建工程的戈壁集料,首先对戈壁集料基本物理性能及矿物成分进行分析,随后以水灰比、戈壁砂率、戈壁细集料种类及水泥浆量为变化参数,先后对戈壁集料混凝土的工作性能、破坏形态以及抗压强度进行研究。试验结果表明:戈壁集料含泥量高,其黏土矿物含量约20%且以吸水能力强的蒙皂石和伊利石为主;随水灰比减小,戈壁粗集料混凝土的坍落度减少,而抗压强度近似线性增大,与普通混凝土规律一致;同配合比下,全戈壁集料混凝土抗压强度高于戈壁粗集料混凝土,但前者的拌合物表现更黏稠;筛除粒径小于0.15 mm的戈壁细集料虽可小幅提高全戈壁集料混凝土的坍落度,但对抗压强度不利;随砂率增加,戈壁集料混凝土的坍落度增大,其抗压强度先增后减。最后,通过回归分析为戈壁集料混凝土配合比提供参考。 展开更多
关键词 戈壁集料混凝土 物理性能 矿物成分 抗压强度 设计建议
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废旧线路板综合回收利用技术研究进展
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作者 柳林 刘红召 +2 位作者 王威 王洪亮 王科 《现代矿业》 CAS 2024年第6期203-208,214,共7页
为了提高电子固体废弃物等二次资源综合利用水平,针对目前废旧线路板存量大,增速快的特点,以及暴力拆解、强酸浸出、污染严重、回收率低等问题,对其物理分选、火法处理、湿法处理等技术手段进行了综述,并分析了不同工艺技术优缺点。最... 为了提高电子固体废弃物等二次资源综合利用水平,针对目前废旧线路板存量大,增速快的特点,以及暴力拆解、强酸浸出、污染严重、回收率低等问题,对其物理分选、火法处理、湿法处理等技术手段进行了综述,并分析了不同工艺技术优缺点。最后指出,废旧线路板等电子固废应当在高效拆解的基础上,使不同组分最大限度解离,再通过火法处理手段利用其中有机组分,通过湿法处理技术回收其中有价金属,最终实现全组分回收以及过程中使用的药剂都循环利用的目的。废旧线路板综合利用未来可在热解设备、新型萃取剂研发等方面进行更加深入的研究。 展开更多
关键词 废旧线路板 有价组分回收 物理分选 火法处理 湿法处理
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基于HHT的绝缘子泄漏电流分析及放电状态分类识别
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作者 方春华 陶玉宁 +3 位作者 吴田 普子恒 丁璨 黎鹏 《高压电器》 CAS CSCD 北大核心 2024年第1期25-32,共8页
泄漏电流是污秽绝缘子在线监测参数,能动态地反映绝缘子表面的放电状态。文中开展了瓷绝缘子人工污秽放电试验,利用Hilbert-Huang变换分析了不同污闪阶段的泄漏电流固有模态函数分量、Hilbert边际谱与时频熵,从时频域及波形细节提取了1... 泄漏电流是污秽绝缘子在线监测参数,能动态地反映绝缘子表面的放电状态。文中开展了瓷绝缘子人工污秽放电试验,利用Hilbert-Huang变换分析了不同污闪阶段的泄漏电流固有模态函数分量、Hilbert边际谱与时频熵,从时频域及波形细节提取了15个特征量,使用主成分分析法与最小二乘支持向量机分类器对污秽放电状态进行识别。结果表明:起始放电阶段与闪络阶段的泄漏电流固有模态函数分量较多;泄漏电流的Hilbert边际谱上频率主要分布在0~150 Hz、200~250 Hz范围内;闪络前泄漏电流的时频熵值总是大于闪络后的;当训练样本数为测试样本数5倍及以上时,分类器的综合评判准确率可达99%,准确实现了污秽放电状态的分类识别。文中研究结果可为建立绝缘子污闪预警系统提供依据。 展开更多
关键词 绝缘子 泄漏电流 HILBERT-HUANG变换 主成分分析法 最小二乘支持向量机 分类识别
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海岸植被防护机制的物理模型试验研究进展
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作者 匡翠萍 丛新 +1 位作者 范家栋 李宏义 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第3期378-387,共10页
基于自然的海岸修复与防护越来越受到人们关注,从海岸植被对水动力及泥沙运动影响机制的物理模型试验研究方面,介绍了试验研究中植被的描述方法,包括植被的分类、材料选择、特性表征等;综述了植被影响下的流场结构、消浪特征、形态阻力... 基于自然的海岸修复与防护越来越受到人们关注,从海岸植被对水动力及泥沙运动影响机制的物理模型试验研究方面,介绍了试验研究中植被的描述方法,包括植被的分类、材料选择、特性表征等;综述了植被影响下的流场结构、消浪特征、形态阻力相关的研究进展;论述了悬沙浓度分布、泥沙再悬浮、沉积和冲刷模式等泥沙输运方面的研究成果;结合大量模型试验研究,提出了未来的研究趋势。 展开更多
关键词 海岸植被 海岸防护 物理模型试验 波流动力 泥沙输运
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