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Terrestrial Temperature, Sea Levels and Ice Area Links with Solar Activity and Solar Orbital Motion
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作者 Valentina V. Zharkova Irina Vasilieva 《Natural Science》 2023年第9期233-255,共23页
This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eig... This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eigenvectors of the solar background magnetic field (SBMF) and with changes of Sun-Earth distances caused by solar inertial motion resulting from the gravitation of large planets in the solar system. Using the wavelet analysis of the GLB and HadCRUTS datasets two periods: 21.4 and 36 years in GLB, set and the period of about 19.6 years in the HadCRUTS are discovered. The 21.4-year period is associated with variations in solar activity defined by the summary curve of the largest eigenvectors of the SBMF. A dominant 21.4-year period is also reported in the variations of the sea level, which is linked with the period of 21.4 years detected in the GLB temperature and the summary curve of the SBMF variations. The wavelet analysis of ice and snow areas shows that in the Southern hemisphere, it does not show any links to solar activity periods while in the Northern hemisphere, the ice area reveals a period of 10.7 years equal to a usual solar activity cycle. The TSI in March-August of every year is found to grow with every year following closely the temperature curve, because the Sun moves closer to the Earth orbit owing to gravitation of large planets (solar inertial motion, SIM), while the variations of solar radiation during a whole year have more steady distribution without a sharp TSI increase during the last two centuries. The additional TSI contribution caused by SIM is likely to secure the additional energy input and exchange between the ocean and atmosphere. 展开更多
关键词 Sun: Magnetic Field Sun: Solar activity Sun: Inertial Motion Earth: Temperature Earth: Sea Level Earth: Ice area
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A Stroke-Limitation AMD Control System with Variable Gain and Limited Area for High-Rise Buildings
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作者 Zuo-Hua Li Qing-Gui Wu +1 位作者 Jun Teng Chao-Jun Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期865-884,共20页
Collisions between a moving mass and an anti-collision device increase structural responses and threaten structural safety.An active mass damper(AMD)with stroke limitations is often used to avoid collisions.However,a ... Collisions between a moving mass and an anti-collision device increase structural responses and threaten structural safety.An active mass damper(AMD)with stroke limitations is often used to avoid collisions.However,a strokelimited AMD control system with a fixed limited area shortens the available AMD stroke and leads to significant control power.To solve this problem,the design approach with variable gain and limited area(VGLA)is proposed in this study.First,the boundary of variable-limited areas is calculated based on the real-time status of the moving mass.The variable gain(VG)expression at the variable limited area is deduced by considering the saturation of AMD stroke.Then,numerical simulations of a stroke-limited AMD control system with VGLA are conducted on a high-rise building structure.These numerical simulations show that the proposed approach has superior strokelimitation performance compared with a stroke-limited AMD control system with a fixed limited area.Finally,the proposed approach is validated through experiments on a four-story steel frame. 展开更多
关键词 High-rise buildings active control stroke limitations variable gain variable limited area
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Impact of climate change and human activities on the spatiotemporal dynamics of surface water area in Gansu Province, China
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作者 LU Haitian ZHAO Ruifeng +3 位作者 ZHAO Liu LIU Jiaxin LYU Binyang YANG Xinyue 《Journal of Arid Land》 SCIE CSCD 2024年第6期798-815,共18页
Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with comp... Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with complex terrain and variable climate,as the research subject.Based on Google Earth Engine,we used Landsat data and the Open-surface Water Detection Method with Enhanced Impurity Control method to monitor the spatiotemporal dynamics of surface water area in Gansu Province from 1985 to 2022,and quantitatively analyzed the main causes of regional differences in surface water area.The findings revealed that surface water area in Gansu Province expanded by 406.88 km2 from 1985 to 2022.Seasonal surface water area exhibited significant fluctuations,while permanent surface water area showed a steady increase.Notably,terrestrial water storage exhibited a trend of first decreasing and then increasing,correlated with the dynamics of surface water area.Climate change and human activities jointly affected surface hydrological processes,with the impact of climate change being slightly higher than that of human activities.Spatially,climate change affected the'source'of surface water to a greater extent,while human activities tended to affect the'destination'of surface water.Challenges of surface water resources faced by inland arid and semi-arid areas like Gansu Province are multifaceted.Therefore,we summarized the surface hydrology patterns typical in inland arid and semi-arid areas and tailored surface water'supply-demand'balance strategies.The study not only sheds light on the dynamics of surface water area in Gansu Province,but also offers valuable insights for ecological protection and surface water resource management in inland arid and semi-arid areas facing water scarcity. 展开更多
关键词 surface water area terrestrial water storage Open-surface Water Detection Method with Enhanced Impurity Control method Google Earth Engine climate change human activities inland arid and semi-arid areas
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ENSO Index Variations and Links with Solar and Volcanic Activity
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作者 Valentina V. Zharkova Irina Vasilieva 《Natural Science》 2024年第4期25-44,共20页
In this paper, we investigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wavelet spectral transform and the IBM SP... In this paper, we investigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wavelet spectral transform and the IBM SPSS correlations analysis. ONI follows the three months’ current measurements of the average temperature of the sea surface in the East-Central tropical part of the Pacific Ocean nearby the international line of the date change over the average sea surface temperature over the past 30 years. The ENSO index is found to have a strong (>87%) correlation with the Global Land-Ocean Temperature (GLOT). The scatter plots of the ENSO-GLOT correlation with the linear and cubic fits have shown that the ENSO index is better fit by the cubic polynomial increasing proportionally to a cubic power of the GLOT variations. The wavelet analysis allowed us to detect the two key periods in the ENSO (ONI) index: 4 - 5 years and 12 years. The smaller period of 4.5 years can be linked to the motion of tectonic plates while the larger period of 12 years is shown to have a noticeable correlation of 25% with frequencies of the underwater (submarine) volcanic eruptions in the areas with ENSO occurrences. Not withholding any local terrestrial factors considered to contribute to the ENSO occurrences, we investigated the possibility of the volcanic eruptions causing ENSO to be also induced by the tidal forces of Jupiter and Sun showing the correlation of the underwater volcanic eruption frequency with the Jupiter-Earth distances to be 12% and with the Sun-Earth distances, induced by the solar inertial motion, in January, when the Earth is turned to the Sun with the southern hemisphere where the ENSO occurs, to become 15%. Hence, the underwater volcanic eruptions induced by tidal forces of Jupiter and Sun can be the essential additional factors imposing this 12 year period of the ENSO (ONI) index variations. 展开更多
关键词 Sun: Magnetic Field Sun: Solar activity Sun: Inertial Motion Earth: Temperature Earth: Sea Level Earth: Ice area
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Interdecadal and decadal variation of temperature over North Pole area and the relation with solar activity 被引量:1
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作者 QU Weizheng ZHAO Jinping DU Ling HUANG Fei FAN Tingting 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第2期53-61,共9页
Obvious tendency and periodicity of the air temperature can be detected over the North Pole area.They are reflected as follows: a.the air temperature at the earth surface and in the middle layer of the stratosphere t... Obvious tendency and periodicity of the air temperature can be detected over the North Pole area.They are reflected as follows: a.the air temperature at the earth surface and in the middle layer of the stratosphere tends to be increased either in winter or in summer.The air temperature has increased 1.3 °C for about 50 years at a speed about 0.025 °C/year in January,and 0.013 °C/year in July.The air temperature in the middle layer of the stratosphere (10 hPa) in January has increased 10 °C.The temperature rising speed in July is 0.14 °C/year.Generally speaking,the temperature rising speed is quicker in winter than in summer and quicker in the upper layer than at the earth surface.b.The air temperature at the top layer of the troposphere (100 hPa) over the North Pole area tends to be increased either in winter or in summer.The air temperature in January has decreased 5.0 °C for about 50 years at a temperature decreasing speed about 0.094 °C/year,and at a temperature decreasing speed about 0.032 °C/year in July.The speed of the temperature decreasing is greater in winter than in summer.c.Periodicity.The air temperature respectively at different altitudes over the North Pole possesses interdecadal variation with a period of 22 years.In July the amplitude of the variation with a period of 22 years decreases rapidly from the high altitude to the low.This means that the 22–year’s period is more obvious at the high altitude than at the low altitude.At the earth surface layer in North Pole there also is obvious decadal variation with a period of 11 years.The analysis indicates that the 22-years’ period temperature variation is associated with the periodic variation of the solar magnetic field.The 11-year period temperature variation is corresponding to 11 year’ period of the variation of the sunspot number. 展开更多
关键词 decadal variation of air temperature solar activity North Pole area
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A statistical reappraisal of the relationship between liquid limit and specific surface area, cation exchange capacity and activity of clays 被引量:1
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作者 Giovanni Spagnoli Satoru Shimobe 《Journal of Rock Mechanics and Geotechnical Engineering》 CSCD 2019年第4期874-881,共8页
More than 500 datasets from the literature have been used to evaluate the relationships of specific surface area (SSA),cation exchange capacity (CEC) and activity versus the liquid limit (LL).The correlations gave R^2... More than 500 datasets from the literature have been used to evaluate the relationships of specific surface area (SSA),cation exchange capacity (CEC) and activity versus the liquid limit (LL).The correlations gave R^2 values ranging between 0.71 and 0.92.Independent data were also used to validate the correlations.Estimated SSA values slightly overestimate the measured SSA up to 100 m^2/g.Regarding the estimated CEC values,they overestimated the measured CEC values up to 20 meq/(100 g).A probabilistic approach was performed for the correlations of SSA,CEC and activity versus LL.The analysis shows that the relations of SSA,CEC and activity with LL are robust.Using the LL values,it is possible to assess other basic engineering properties of clays. 展开更多
关键词 Liquid limit(LL) Specific surface area(SSA) Cation exchange capacity(CEC) activity statistical analysis
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High surface area biocarbon monoliths for methane storage 被引量:1
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作者 Elizabeth Michaelis Renfeng Nie +1 位作者 Douglas Austin Yanfeng Yue 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第5期1308-1324,共17页
New energy sources that reduce the volume of harmful gases such as SO_(x)and NO_(x)released into the atmosphere are in constant development.Natural gas,primarily made up of methane,is being widely used as one reliable... New energy sources that reduce the volume of harmful gases such as SO_(x)and NO_(x)released into the atmosphere are in constant development.Natural gas,primarily made up of methane,is being widely used as one reliable energy source for heating and electricity generation due to its high combustion value.Currently,natural gas accounts for a large portion of electricity generation and chemical feedstock in manufacturing plastics and other commercially important organic chemicals.In the near future,natural gas will be widely used as a fuel for vehicles.Therefore,a practical storage device for its storage and transportation is very beneficial to the deployment of natural gas as an energy source for new technologies.In this tutorial review,biomaterials-based carbon monoliths(CMs),one kind of carbonaceous material,was reviewed as an adsorbent for natural gas(methane)adsorption and storage. 展开更多
关键词 Activated carbon Carbon monolith Methane storage High surface area Activation agent
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The characteristics of Quaternary activity of faults in the sea area near the Yangtze River mouth
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作者 ZHANG Zhen-quan(章振铨) +5 位作者 HUO En-jie(火恩杰) LIU Chang-sen(刘昌森) WANG Feng(王锋) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第4期473-479,共7页
By shallow seismic prospecting, it is showed that the faults in the sea area near the Yangtze River mouth are mainly the NE and NW-trending faults. The main activity time of fault is Pliocene to Early Pleistocene, and... By shallow seismic prospecting, it is showed that the faults in the sea area near the Yangtze River mouth are mainly the NE and NW-trending faults. The main activity time of fault is Pliocene to Early Pleistocene, and the latest activity is up to Middle Pleistocene. The maximum of fault is generally several tens meters with the throw decreased upward. The dislocation near the bottom of Middle Pleistocene is 12~13 m. The average vertical dis-placement rate is on a level of 10-3 mm/a. 展开更多
关键词 FAULT activity sea area near the Yangtze River mouth
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Ventral Tegmental Area Neuronal Activity Correlates to Animals’ Behavioral Response to Chronic Methylphenidate Recorded from Adolescent SD Male Rats
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作者 Zachary Jones Cruz Reyes Vazquez Nachum Dafny 《Journal of Behavioral and Brain Science》 2014年第4期168-189,共22页
Methylphenidate (MPD) is considered as the first-line pharmacotherapy to treat ADHD. More recently, MPD has also been used as a cognitive enhancement recreationally. Its therapeutic effects are not fully understood, n... Methylphenidate (MPD) is considered as the first-line pharmacotherapy to treat ADHD. More recently, MPD has also been used as a cognitive enhancement recreationally. Its therapeutic effects are not fully understood, nor are the long term effects of the drug on brain development. The ventral tegmental area (VTA) neuronal activity was recorded from freely behaving adolescent rats using a wireless recording system. Five groups were used: saline, 0.6, 2.5, 5.0 and 10.0 mg/kg MPD. The experiment lasted for 10 days. This study demonstrated that VTA neurons respond to MPD in a dose response characteristic and the same dose of MPD can cause both behavioral sensitization and behavioral tolerance. The neuronal unit activity was evaluated based on the animals’ behavioral activity following chronic MPD administration. The study showed that the animals’ behavioral response to different acute MPD of 0.6, 2.5 and 10.0 mg/kg doses responded in a dose response characteristics. Moreover, the same chronic dose of 0.6, 2.5, and 10.0 mg/kg MPD elicits in some animals’ behavioral sensitization and in some others behavioral tolerance. Therefore, the neuronal activity recorded from animals expressing behavioral sensitization was analyzed separately from the neuronal activity recorded from of behaviorally tolerant animals and it was found that the VTA units of the behaviorally sensitization animals responded significantly different to the drug than those VTA units recorded from animals expressing behavioral tolerance. 展开更多
关键词 RITALIN ELECTROPHYSIOLOGY Neuronal activity Behavior VENTRAL Tegmental area
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Suitability Evaluation of Physical Activity Places in Urban Parks for Children's Play Activities:A Case Study of Four Urban Parks in Handan
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作者 REN Hongguo AO Hanjun 《Journal of Landscape Research》 2022年第3期27-32,共6页
Taking 4 urban parks in Handan City as the research objects, 41 suitability evaluation indicators are selected according to the relevant literature reading. The common factors are extracted through factor analysis and... Taking 4 urban parks in Handan City as the research objects, 41 suitability evaluation indicators are selected according to the relevant literature reading. The common factors are extracted through factor analysis and the importance questionnaire and summarized into 6 dimensions, namely children's play facilities and auxiliary facility quality factor, natural environment participation factor, children's play space convenience factor, artificial environment participation factor, space environment quality and safety factor, children's game activity facility perfection factor, and the weights of public factors and indicators are calculated. Then the index score is calculated through field measurement and satisfaction survey, and the IPA analysis method is used to draw the coordinate map of key optimization indicators for 4 parks. Finally, corresponding optimization suggestions are put forward for Handan urban parks according to the analysis and evaluation results. 展开更多
关键词 Urban park Physical activity children's play Built environment Factor analysis
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Active Fault and Volcanic Activity in the Longhai-Zhangpu Coastal Area, Fujian Province
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作者 Huang Qingtuan Zhuang Jinyao +1 位作者 Xie Zhizhao Zhang Qingxiang 《Earthquake Research in China》 2005年第2期214-223,共10页
The Longhai-Zhangpu coastal region lies in the so-called Golden Triangle area of southern Fujian Province. Tectonically, it is located on the southern segment of the Changle-Zhao'an fault zone, being one of the regio... The Longhai-Zhangpu coastal region lies in the so-called Golden Triangle area of southern Fujian Province. Tectonically, it is located on the southern segment of the Changle-Zhao'an fault zone, being one of the regions of Tertiary and Quaternary basaltic eruptions in China's southeast coastal area. In this area there are the Liuhui (Longhai County )-Jiangjun' ao (Zhangpu County) and Gangwei ( Longhai County )-Huxi ( Zhangpu County ) faults, along which basaltic eruption has occurred. The faults have been significantly active since the Quaternary, and several small to moderate earthquakes have occurred on the faults. In this paper, the basic characteristics of the late Quaternary activities and the combination relation of the faults are discussed on the basis of an analysis of along-fault basaltic eruptions during the late Tertiary to late Pleistocene, as well as the differential variation of geomorphic surfaces and marine deposits on both sides of the faults. The results show that the Liuhui-Jiangjun'ao fault is a late Pleistocene active fault. During the late Tertiary to late Pleistocene, three stages of basaltic eruptions occurred along the fault, among which the first stage occurred in the Pleistocene to early Pleistocene, the second stage in the middle Pleistocene and the third stage in the late Pleistocene. The Gangewei-Huxi fault can also be considered a late Pleistocene active fault. The elevation rate of the downthrown side of the fault is estimated to be 1. 11mm/a.These two faults have dissected the area into the Gangwei graben, south Taiwushan horst and the graben in the sea area to the east of Liuhul-Jiangjun'ao. 展开更多
关键词 Longhai-Zhangpu costal area Active fault Volcanic eruption
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Characteristics of Fault Activity in the Taiyangshan Uplift Area in Hunan,China
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作者 Shen Dexiu Zhou Bengang +2 位作者 Yang Xiaoping Zhong Puyu Liu Xia 《Earthquake Research in China》 2008年第4期391-401,共11页
Lying on the west edge of Dongting Lake,the Taiyangshan area in Hunan Province is part of a hilly region which has uplifted since the Late Cenozoic.According to field investigation of the six existing faults in the Ta... Lying on the west edge of Dongting Lake,the Taiyangshan area in Hunan Province is part of a hilly region which has uplifted since the Late Cenozoic.According to field investigation of the six existing faults in the Taiyangshan area,we found that four of them are not active in the Quaternary,and that the Gangshi-Hefu fault is likely to have been active in the early Mid-Pleistocene.The geological evidence derived suggests that the Xiaowupu fault was active from the late Mid-Pleistocene to the early late-Pleistocene.It cut the stratum with a TL age of 123±10ka BP and has the property of thrusting.The research results are of great significance for understanding the seismogenic structure of the Changde earthquake with M6 3/4 in 1631. 展开更多
关键词 Taiyangshan uplift area Fault activity Seismogenic structure
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川西巴塘地区富锂温泉的同位素特征及其成因探讨 被引量:2
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作者 胡志华 田建吉 +7 位作者 吕菲 刘畅 雷鸣宇 万汉平 郝伟林 张松 高洪雷 吴儒杰 《世界核地质科学》 CAS 2024年第1期88-104,共17页
川西巴塘地区处于青藏高原东南缘,是地壳新构造运动活跃、地震活动强烈而密集的地区,其中茶洛—德达地段是温泉聚集区,富锂沸泉与温泉密集发育。为进一步认识该区富锂温泉的成因以及温泉与地震活动的关系,开展了温泉水氢、氧、碳和锂同... 川西巴塘地区处于青藏高原东南缘,是地壳新构造运动活跃、地震活动强烈而密集的地区,其中茶洛—德达地段是温泉聚集区,富锂沸泉与温泉密集发育。为进一步认识该区富锂温泉的成因以及温泉与地震活动的关系,开展了温泉水氢、氧、碳和锂同位素的综合研究,阐明了地热流体、锂和热量的来源,探讨了富锂温泉的成因及其与地震活动的关系,为该区富锂温泉的研究和勘查提供支撑。研究结果显示:1)茶洛—德达地段发育章柯、茶洛富锂沸泉和查青卡富锂温泉,锂含量高达1353.00~3592.00µg·L^(-1),其锂同位素组成δ7Li介于-0.53‰~1.74‰之间;2)该区富锂温泉水主要来源于周边4800~5200 m的高山区域大气降水,温泉流体循环深度可达6900~8500 m,与该区部分地震的震源深度相当;3)富锂温泉的深部发生较强的高温(温度236~289℃)水-岩反应,碳酸盐岩、富锂花岗岩等释放出碳和锂等元素,形成查青卡富锂温泉(1353~1392µg·L^(-1));章柯、茶洛沸泉除上述锂来源外,还有深部高温富锂流体混入,从而形成更高温(240~289℃)、更富锂(2736~3592µg·L^(-1))的地热流体;4)该区章柯、茶洛富锂沸泉的热源除以深部(地壳、地幔)热流为主要热源外,还有地震断层摩擦热、深部流体热为补充热源,频发的地震活动持续地、脉动式地为章柯、茶洛地热系统补充热量,形成富锂沸泉。查青卡富锂温泉热源主要为深部(地壳、地幔)热流,无断层摩擦热和深部流体热补充。 展开更多
关键词 富锂温泉 同位素 地震活动 成因 川西巴塘地区
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城乡融合背景下乡村地区存量用地潜力与利用路径分析——以江苏省丰县为例 被引量:1
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作者 李红波 胡正玉 周家乐 《贵州师范大学学报(自然科学版)》 CAS 北大核心 2024年第2期21-28,共8页
存量用地的盘活利用是土地整理的重要组成部分之一,盘活存量资源、创新存量规划已成为当前城乡发展的新命题。构建了存量用地从提取到综合评价与潜力测算应用的框架体系,分析丰县乡村地区存量用地空间分布与规模特征,测算镇域尺度下乡... 存量用地的盘活利用是土地整理的重要组成部分之一,盘活存量资源、创新存量规划已成为当前城乡发展的新命题。构建了存量用地从提取到综合评价与潜力测算应用的框架体系,分析丰县乡村地区存量用地空间分布与规模特征,测算镇域尺度下乡村地区存量用地再开发潜力,提出存量用地盘活路径与政策建议。研究表明:1)丰县乡村地区存量用地的整体盘活潜力可观,各街镇开发改造潜力差异较大。2)丰县乡村地区存量用地潜力分为三级潜力区,分布不均衡,靠近主城区的街镇潜力较大且多集中于南部。3)乡村存量用地盘活应该采取不同类型村庄差异化发展、乡村规划与盘活政策有机衔接、创新用地增减挂钩制度等有效路径。 展开更多
关键词 存量用地 乡村地区 潜力测算 利用路径 丰县
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经CT扫描探讨正常喉的活动度的研究
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作者 梁健 申静 +7 位作者 李雯 王斐然 赵宇明 白洪忠 李华 赵敏 郝濛 梁香存 《中国CT和MRI杂志》 2024年第1期31-34,共4页
目的通过对喉部活动度进行测量,进一步精确勾画喉外扩靶区,以实现肿瘤精确放疗提高放疗效果。方法选取51例肿瘤患者为研究对象,通过CT测量喉部在四个方向最大活动度,通过spss23.0对实验所得数据进行统计分析。结果51位研究对象平均前联... 目的通过对喉部活动度进行测量,进一步精确勾画喉外扩靶区,以实现肿瘤精确放疗提高放疗效果。方法选取51例肿瘤患者为研究对象,通过CT测量喉部在四个方向最大活动度,通过spss23.0对实验所得数据进行统计分析。结果51位研究对象平均前联合向上最大移动范围为(13.04±6.72)mm,前联合向下最大移动范围为(1.53±2.41)mm,前联合向左最大移动范围为(1.44±1.74)mm,前联合向右最大移动范围为(1.35±2.27)mm,前联合向前最大移动范围为(3.81±2.74)mm,前联合向后最大移动范围为(0.75±1.59)mm,左侧甲状软骨板最大外移为(0.70±1.21)mm,左侧甲状软骨板最大内移为(1.86±2.85)mm,右侧甲状软骨板最大外移为(0.70±1.35)mm,右侧甲状软骨板最大内移为(1.42±1.71)mm,杓前角最大间距为(14.15±3.51)mm。以第一次测量为准确测量值,第二次、第三次测量值与第一次测量值差值绝对值为误差值,比较两次测量误差值。两次测量误差间差异无统计学意义(P>0.05)。≤60岁研究对象与>60岁研究对象的喉部活动度无显著性差异(P>0.05)。男性杓前角最大间距为(15.32±4.72)mm,显著高于女性的(12.14±1.61)mm,差异具有统计学意义(P<0.05)。转移的研究对象左侧甲状软骨板最大内移为(2.36±2.11)mm,显著高于未转移的(1.19±1.73)mm,差异具体统计学意义(P<0.05)。性别与前联合向上最大移动范围、杓前角最大间距呈现显著负相关(P<0.05),与左侧甲状软骨板最大外移呈显著正相关(P<0.05);年龄与前联合向上最大移动范围呈显著正相关(P<0.05),与前联合向下最大移动范围、左侧甲状软骨板最大外移呈显著负相关(P<0.05)。皮尔逊相关性分析发现甲状软骨板前联合向左移动度与左侧甲状软骨板最大外移具有显著正相关性(r=0.301,P=0.032);甲状软骨板前联合向右移动度与右侧甲状软骨板最大外移具有显著正相关性(r=0.072,P=0.000)。结论自然吞咽会引起喉部运动,这种运动的具体范围在肿瘤放射治疗中需被注意。 展开更多
关键词 CT 喉部活动 放射治疗 靶区
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鄂尔多斯盆地富县地区马家沟组热液改造特征与研究意义
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作者 齐荣 李国蓉 +7 位作者 张军涛 王付斌 李宇翔 杨飞 刘璐 何赛 田家奇 李肖肖 《古地理学报》 CAS CSCD 北大核心 2024年第3期632-643,共12页
构造—热事件对油气生成、储集层演化和成藏有重要的控制作用,但是鄂尔多斯盆地构造—热事件对碳酸盐岩的影响研究较少。以富县地区奥陶系马家沟组储集层为例,通过岩心及薄片观察,利用阴极发光、包裹体测温、碳氧稳定同位素、锶同位素... 构造—热事件对油气生成、储集层演化和成藏有重要的控制作用,但是鄂尔多斯盆地构造—热事件对碳酸盐岩的影响研究较少。以富县地区奥陶系马家沟组储集层为例,通过岩心及薄片观察,利用阴极发光、包裹体测温、碳氧稳定同位素、锶同位素、电子探针微区元素分析、稀土元素分析,岩石学与地球化学研究充分结合,识别出区内存在2期与燕山期热事件相关的胶结作用:第Ⅰ期以缝洞内鞍形白云石发育为特征,其δ^(13)C值和δ^(18)O值均较偏负,锶同位素值较正常海相灰岩高,稀土元素Eu和La负异常,元素分析显示FeO含量异常高、MnO含量较高、SrO含量较高、K_(2)O及Na_(2)O含量低,胶结物包裹体均一温度高;第Ⅱ期以缝孔洞内石英充填及交代和切割鞍形白云石的裂缝方解石发育为特征,其δ^(13)C值与奥陶系碳酸盐岩背景值接近、δ^(18)O值总体偏低,锶同位素值更高,稀土元素展现出特别的La负异常和Eu正异常,元素分析MnO及FeO含量较高,部分K_(2)O及Na_(2)O含量较高,石英包裹体均一温度高。第Ⅰ期流体为早白垩世拉张断裂作用下上覆石炭—二叠系地层有机流体、奥陶系地层内部流体、少量深部流体三者联合作用形成;第Ⅱ期流体为早白垩世拉张断裂作用下深部流体与少量奥陶系地层内部流体两者联合作用形成,深部流体穿越了下伏马家沟组内蒸发盐岩地层。早白垩世热事件对奥陶系碳酸盐岩储集层的影响具有双向性:第Ⅰ期热流体活动多为建设性,与大规模油气生成的时间一致,裂缝和溶蚀孔洞可构成油气有效输导和储集空间;第Ⅱ期热流体活动以孔隙和裂缝充填为主,多为破坏性,但规模较小。 展开更多
关键词 鄂尔多斯盆地 富县地区 马家沟组 碳酸盐岩 热液作用
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平顶山矿区多煤层卸压立体抽采模式与工程示范
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作者 李延河 倪小明 贾晋生 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第9期162-172,共11页
平顶山矿区多煤层发育、含气层段多,仅靠井下进行瓦斯治理工程量大、难度高。为了开辟平顶山矿区瓦斯抽采新模式,达到“采一层抽多层”的目的,采用气测录井与含气量测试相结合的方法精准判识了煤系主要含气层段和含气量;采用体积法评价... 平顶山矿区多煤层发育、含气层段多,仅靠井下进行瓦斯治理工程量大、难度高。为了开辟平顶山矿区瓦斯抽采新模式,达到“采一层抽多层”的目的,采用气测录井与含气量测试相结合的方法精准判识了煤系主要含气层段和含气量;采用体积法评价了东部5对矿井采动区和采空区的煤系气资源量。基于“O”形圈理论和“防-抗-让”思想,分别优化设计了采动井、采空井的井位、层位和井身结构,构建了采动区、采空区多煤层卸压立体抽采模式并进行了工程示范。结果表明:(1)二_(1)煤层顶板200 m范围内存在四煤组、三煤组、二_(1)煤层顶板60 m范围内的砂岩/泥质砂岩互层段等3处主要含气段。平顶山矿区东部5对矿井的采动区和采空区资源量分别为26.36×10~8 m^(3)和20.00×10~8 m^(3)。(2)采动井最佳井位为0.17~0.28倍采长,且靠近回风巷条带区域;走向上,采动井的间距一般为80~100 m。创建了“大口径、避开岩体变形强烈区、P110梯型扣套管”的采动直井稳孔技术体系和“下行水平轨迹+提高套管强度”的采动L型水平井稳产技术体系,保证了产气通道的畅通性。采空井一般布置在距离回风巷30~50 m的区域,完钻位置一般为二_(1)煤层顶板40~60 m的范围;筛管布置在四煤段顶板至裂隙带底部。(3)建立了“地面采动直井/定向井-采动L型水平井-采空井”联作的卸压立体抽采模式,实现了多气源立体抽采。截至2024年4月30日,累计抽采纯量达5258.8万m^(3),总利用量达到3735.4万m^(3),率先在河南省实现了煤系气产业化开发,示范和引领带动作用显著。 展开更多
关键词 煤系气 多煤层卸压 立体抽采模式 采动区 采空区 平顶山矿区
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坝上地区莜麦秸秆热解特性研究
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作者 刘联胜 梁小虎 +2 位作者 王冬计 张晓宇 黄亚龙 《可再生能源》 CAS CSCD 北大核心 2024年第3期293-299,共7页
为实现高寒坝上地区农作物秸秆高效清洁燃烧,文章选取典型莜麦秸秆作为研究对象,通过混合气体模拟烟气燃烧过程中的热解气氛环境,采用热重分析仪研究空气和N_(2),CO_(2),O_(2)不同比例组成的混合气体氛围下热失重特性以及升温速率对其影... 为实现高寒坝上地区农作物秸秆高效清洁燃烧,文章选取典型莜麦秸秆作为研究对象,通过混合气体模拟烟气燃烧过程中的热解气氛环境,采用热重分析仪研究空气和N_(2),CO_(2),O_(2)不同比例组成的混合气体氛围下热失重特性以及升温速率对其影响,采用AKTS软件进行动力学分析。结果表明:莜麦秸秆热解过程可分为干燥(30~140℃)、挥发(140~370℃)、炭化(370~900℃)3个阶段;气体氛围主要影响热解的炭化阶段,对干燥和挥发阶段影响较小;升温速率影响挥发和炭化阶段,升温速率越快,反应速率越大;当热解气氛为15%O_(2)-5%CO_(2)-80%N_(2)混合气体(气体2)时,热解过程所需活化能最少,平均活化能为139.86 kJ/mol。研究结果可为高寒坝上地区生物质秸秆能源化利用提供一定理论依据。 展开更多
关键词 坝上地区 莜麦秸秆 热解特性 活化能
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冻融条件下路基温度场和湿度场分布式感知试验
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作者 凌建明 张玉 +2 位作者 钱劲松 吴振吉 郑纯宇 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第4期582-591,共10页
搭建土体冻融多物理场感知室内试验装置,布设传统点式传感器和分布式光纤,对土体冻融过程中路基温度场、湿度场和变形情况开展试验监测,探究单端冻结、双端融化条件下土体温度场和湿度场的分布式感知特征,验证主动加热分布式光纤技术的... 搭建土体冻融多物理场感知室内试验装置,布设传统点式传感器和分布式光纤,对土体冻融过程中路基温度场、湿度场和变形情况开展试验监测,探究单端冻结、双端融化条件下土体温度场和湿度场的分布式感知特征,验证主动加热分布式光纤技术的监测效果。试验结果表明,-15℃单端冻结条件下,土体冻结过程按降温速率分为快速冷却、逐步降温、稳定平衡三阶段,冻结锋面逐渐下移,最大冻深约占土柱高度的35%。孔隙水受冻胀迁移力影响向冻结锋面移动,引起冻融前后土体湿度场重分布,并导致土体冻胀变形,变形量为土体最大冻深的7.8%~10.9%。分布式光纤可准确得到冻融过程中土体温度场、湿度场变化特征,识别土体内冻结区域范围,温度、湿度监测拟合优度R2分别达0.98和0.94。 展开更多
关键词 路基工程 温度场 湿度场 分布式感知 季冻区路基 主动加热光纤
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稻草秸秆-煤基压块活性炭的制备及工艺优化
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作者 李晶 徐国忠 +1 位作者 李扬 张生刚 《辽宁科技大学学报》 CAS 2024年第1期25-31,共7页
为降低压块破碎活性炭的制备成本,以稻草秸秆炭和大同不黏煤为主要原料,利用配煤工艺,经过成型、炭化、H_(2)O_((g))-CO_(2)联合活化成型炭制备压块破碎活性炭。采用碘吸附法、亚甲蓝吸附法以及BET、FTIR和Boehm滴定方法测试和表征不同... 为降低压块破碎活性炭的制备成本,以稻草秸秆炭和大同不黏煤为主要原料,利用配煤工艺,经过成型、炭化、H_(2)O_((g))-CO_(2)联合活化成型炭制备压块破碎活性炭。采用碘吸附法、亚甲蓝吸附法以及BET、FTIR和Boehm滴定方法测试和表征不同条件下制备的压块破碎活性炭。实验结果表明,加入适量稻草秸秆炭和H_(2)O_((g))-CO_(2)联合活化对活性炭的碘吸附值和亚甲蓝吸附值均有明显提升作用。Boehm滴定结果表明,活性炭具有丰富的酸性和碱性官能团。当活化温度为900℃、活化时间为2.5 h、H_(2)O_((g))和CO_(2)流量比为2时,制备的活性炭的碘吸附值、亚甲蓝吸附值和比表面积分别达到790 mg/g、262 mg/g和809 m^(2)/g。 展开更多
关键词 活性炭 比表面积 碘吸附值
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