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论歌唱中的内敛反射力
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作者 张淑芳 《音乐创作》 2007年第6期136-138,共3页
本文剖析了“用心歌唱”的完整含意,进而提出了“内敛反射力”这一歌唱发声概念,并就此概念进行了阐述,以期在歌唱心理与歌唱技能技巧之间搭建一个有助于促进其有机结合的、又可把握的“桥梁”,试图用“内敛反射力”概念去解释、注... 本文剖析了“用心歌唱”的完整含意,进而提出了“内敛反射力”这一歌唱发声概念,并就此概念进行了阐述,以期在歌唱心理与歌唱技能技巧之间搭建一个有助于促进其有机结合的、又可把握的“桥梁”,试图用“内敛反射力”概念去解释、注释歌唱的心理教学的内涵。 展开更多
关键词 “用心歌唱” 歌唱心理概念 歌唱的技能技巧 内敛反射 整体把握
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基于被动力反馈的遥操作电液控制系统
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作者 李元鹏 郭疆 邵明东 《机械与电子》 2015年第11期47-49,共3页
针对遥操作机器人现有的力反馈冲击、反馈力震荡等问题,提出了一种新型的遥操作电液控制系统。主操作端选用电液比例控制系统以实现力反馈效果,从动端选用电液伺服控制系统以实现位移跟踪效果,并建立了电液控制系统的数学模型,选用算法... 针对遥操作机器人现有的力反馈冲击、反馈力震荡等问题,提出了一种新型的遥操作电液控制系统。主操作端选用电液比例控制系统以实现力反馈效果,从动端选用电液伺服控制系统以实现位移跟踪效果,并建立了电液控制系统的数学模型,选用算法简单、跟踪性能较好的力反射型控制策略,对整个系统进行了Matlab/Simulink仿真,结果表明,新型遥操作电液控制系统具有较好的位移跟踪及力反馈效果。 展开更多
关键词 遥操作 电液控制 力反射 仿真
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主/从机器人系统设计与双向伺服控制 被引量:5
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作者 陈铁华 赵丁选 张祝新 《农业机械学报》 EI CAS CSCD 北大核心 2008年第12期141-145,共5页
建立了主/从异构式机器人力反馈遥操作控制系统。主操作系统采用2个2-DOF操作手,分别采用伺服阀控制液压马达获得2个解耦的旋转自由度。用力信息对伺服阀进行控制以驱动主操作手运动,解决主手操纵力不能直接驱动主操作手液压马达的问题... 建立了主/从异构式机器人力反馈遥操作控制系统。主操作系统采用2个2-DOF操作手,分别采用伺服阀控制液压马达获得2个解耦的旋转自由度。用力信息对伺服阀进行控制以驱动主操作手运动,解决主手操纵力不能直接驱动主操作手液压马达的问题。从机器人为4-DOF串联关节型四自由度机器人,采用比例方向阀控制。分别采用力反射伺服型和力对称型双向伺服控制策略,对主/从机器人系统进行遥操作力反馈双向伺服控制实验研究。验证了本设计的主操作手结构的合理性,力对称型双向伺服控制策略具有较好的控制性能。 展开更多
关键词 主/从机器人 觉临场感 电液伺服系统 力反射伺服型控制策略 对称型伺服控制策略
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Design and evaluation of epoxy asphalt geogrid stress- absorbing layer 被引量:4
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作者 薛永超 钱振东 贾文镖 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期93-98,共6页
In order to delay or eliminate the occurrence and expansion of the reflective cracking in the asphalt concrete overlay on old cement concrete pavement, an epoxy asphalt geogrid stress-absorbing layer( EAGSAL) was de... In order to delay or eliminate the occurrence and expansion of the reflective cracking in the asphalt concrete overlay on old cement concrete pavement, an epoxy asphalt geogrid stress-absorbing layer( EAGSAL) was designed. The EAGSAL consists of epoxy asphalt and fiberglass geogrid. The pull-out test, skewshearing test, bending beam test and fatigue test were conducted to evaluate the performance of the EAGSAL and a traditional stress-absorbing layer( TSAL). The results showthat the adhesive performance, shear performance, bending strength and fatigue performance of the EAGSAL with an optimal spraying volume of epoxy asphalt are better than those of optimally designed TSAL, and the maximum bending strain of the EAGSAL is very close to that of the TSAL. The EAGSAL has superior performance in reflective cracking resistance.Moreover, the EAGSAL with the optimal spraying volume of approximately 2. 0 L m^2 is thinner and lighter than the TSAL,which can decrease the thickness and improve the bearing ability of the whole pavement structure. 展开更多
关键词 asphalt concrete overlay stress-absorbing layer reflective cracking resistance epoxy asphalt fiberglass geogrid
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Full Quantum State Resolved Scattering Dynamics of the F+H_(2)→HF+H Reaction at 5.02 kJ/mol 被引量:1
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作者 邱明辉 任泽峰 +4 位作者 车丽 戴东旭 史提夫 王秀岩 杨学明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期93-95,共3页
A crossed molecular beams, state-to-state scattering study was carried out on the F+H2→HF+H reaction at the collision energy of 5.02 kJ/mol, using the highly sensitive H atom Rydberg tagging time-of-flight method. ... A crossed molecular beams, state-to-state scattering study was carried out on the F+H2→HF+H reaction at the collision energy of 5.02 kJ/mol, using the highly sensitive H atom Rydberg tagging time-of-flight method. All the peaks in the TOF spectra can be clearly assigned to the ro-vibrational structures of the HF product. The forward scattering of the HF product at v′=3 has been observed. The small forward scattering of the HF product at v′=2 has also been detected. Detailed theoretical analysis is required in order to fully understand the dynamical origin of these forward scattering products at this high collision energy. 展开更多
关键词 Crossed molecular beams Reactive scattering State-to-state dynamics Reaction resonance
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A dynamic performance evaluation method based on SD-BSC 被引量:1
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作者 滕春贤 潘晓东 胡宪武 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第3期398-403,共6页
Taking into consideration the disadvantage of Balanced Scorecard(BSC)not being able to reflect time delay,nonlinear problems of causal relationship and being lack of effective simulation,we combined it with the charac... Taking into consideration the disadvantage of Balanced Scorecard(BSC)not being able to reflect time delay,nonlinear problems of causal relationship and being lack of effective simulation,we combined it with the characteristics of the System Dynamics(SD).Basing on the background of manufacturing enterprises,through SD integrating with the BSC we established a new performance evaluation method-SD-BSC method to overcome the disadvantage of BSC.A performance evaluation model of SD-BSC is provided and the simulation results are analyzed which show different production policies will lead to different customer's satisfaction degrees.The SD-BSC dynamic performance evaluation method can reflect dynamic,complex causal feedback relationship and time delay,so it compensates for the disadvantage of traditional financial performance evaluation method,and at the same time makes the BSC perfect. 展开更多
关键词 performance evaluation Balanced Scorecard System Dynamics SD-BSC
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Bond interface crack propagation of fresh foundation concrete and rock under blasting load 被引量:1
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作者 WU Liang LU Wen-bo ZHONG Dong-wang 《Journal of Coal Science & Engineering(China)》 2009年第1期61-65,共5页
According to concrete age, the dynamic stress intensity factors of bond interface crack of concrete-rock was calculated. Result shows that the propagation of concreteinterface crack is mainly caused by tensile stress ... According to concrete age, the dynamic stress intensity factors of bond interface crack of concrete-rock was calculated. Result shows that the propagation of concreteinterface crack is mainly caused by tensile stress and shear stress for stress wave reflection. With the growth of concrete age, interface crack fracture toughness increases, and itscapacity of resisting blasting load strengthens. Therefore, blasting vibration should bestrictly controlled for fresh concrete. 展开更多
关键词 fresh concrete dynamic stress intensity factors numerical calculation
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Determination of Water Colltent in Clayey Red Soil Using Techniques Based on Measurement of Dielectric Constant 被引量:1
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作者 ZHANGBIN GAOGUOZHI 《Pedosphere》 SCIE CAS CSCD 1997年第2期149-154,共6页
Two time-domain reflectometry (TDR) systems and a new impedance measuring instrument, Thetaprobe,which are based on determination of soil dielectric constant, were used to measure water content of clayeyred soil to er... Two time-domain reflectometry (TDR) systems and a new impedance measuring instrument, Thetaprobe,which are based on determination of soil dielectric constant, were used to measure water content of clayeyred soil to eraluate the accuracy of these instruments. The results indicated that these instruments shouldbe carefUlly re-calibrated before being applied in clayey red soil. With a new calibration curve fed into one ofthe TDR systems tested, nase system, the measured data compared well with tho8e by standard oven-dryingmethod. 展开更多
关键词 clayey red soil dielectric constant soil water content time-domain refiectometry (TDR)
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Factors affecting the dynamic response of pre-stressed anchors after transient excitation 被引量:1
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作者 Xu Huijun Li Qingfeng 《Mining Science and Technology》 EI CAS 2011年第3期395-399,共5页
The wide application of pre-stressed bolting technology in coal mine tunnels has made the nondestructive stress wave reflection method of determining bolting quality an important one. The effect of the support plate o... The wide application of pre-stressed bolting technology in coal mine tunnels has made the nondestructive stress wave reflection method of determining bolting quality an important one. The effect of the support plate on the dynamic response of the pre-stressed anchor is of particular interest. A theoretical analysis and numerical simulations are used to identify the factors affecting the contact stress between the support plate and the rock wall. A formula allowing the calculation of contact stress is presented. Stress wave propagation through the nut, support plate, and rock wall are predicted. The dynamic response signals were measured in the field using prestressed anchors pre-tightened to different torques. The effects from the support plate on the dynamic response were recorded and the results compared to the predictions of pre-stressed anchor. This work provides a theoretical reference for the signal processing of dynamic reflected wave signals in anchor bolts. 展开更多
关键词 Support plate effectContact stressPre-stressed anchorDynamic response
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Reaction thrust characteristics of high-pressure submerged water jet of cylinder nozzles 被引量:1
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作者 李晓晖 《Journal of Chongqing University》 CAS 2009年第1期63-69,共7页
The shapes and geometrical parameters of nozzles are key factors for fluidics. The relationship among the reaction thrust, flow rate pressure, diameter do and length L of a cylinder nozzle is analyzed theoretically. T... The shapes and geometrical parameters of nozzles are key factors for fluidics. The relationship among the reaction thrust, flow rate pressure, diameter do and length L of a cylinder nozzle is analyzed theoretically. The simulation of the flow field characteristics was conducted via the FLUENT computational fluid dynamics package. Effects of the inlet conditions and the nozzle dimensions on the reaction thrust of a water jet were addressed particularly. The reaction thrust experiments were performed on a custom-designed test apparatus. The experimental results reveal that a) the nozzle diameter and the inlet conditions exert great influence on the water jet reaction thrust; and b) for L≤4d0, where the nozzle is treated as a thin plate-orifice, the reaction thrust is independent of nozzle length; for L〉4d0, where the nozzle is treated as a long orifice, the reaction thrust can reach maximum under the condition of a certain flow rate. These findings lay a theoretical foundation for the design of nozzles and have significant value, especially for the future development of high-oressure water-let orooulsion technology. 展开更多
关键词 cylindrical nozzle pressure distribution reaction thrust characteristics turbulent flow water jet
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Effect of Microinfusion of Angiotensin Ⅱ into the RVLM in Rats on the Baroreceptor Reflex Sensitivity 被引量:4
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作者 ZHANGFeng GAOXing-ya ZHUGuo-qing ZHONGWan-hua 《Journal of Nanjing Medical University》 2004年第3期121-124,共4页
Objective: The present study was designed to investigate the effect of microinfusion angiotensin Ⅱ(Ang Ⅱ),Ang Ⅱ type 1(AT_1)receptor antagonist losartan into the rostral ventrolateral medulla(RVLM)on the barorecept... Objective: The present study was designed to investigate the effect of microinfusion angiotensin Ⅱ(Ang Ⅱ),Ang Ⅱ type 1(AT_1)receptor antagonist losartan into the rostral ventrolateral medulla(RVLM)on the baroreceptor reflex sensitivity(BRS)in urethane-anesthetized rats. Methods: Reflex changes in heart rate(HR)were elicited by bolus intravenous injection of phenylephrine before and during RVLM microinfusion of saline(0.5 μl/h),Ang Ⅱ (1.5 nmol/h),losartan(250 nmol/h),and Ang Ⅱ(1.5 nmol/h)pretreated with microinjection of losartan (50 nmol/0.51 μl)into the RVLM.The average ratio between changes in HR in beats per minute(beats·min -1)and changes in mean arterial pressure [MAP,mmHg(1 mmHg=0.133 kPa)] was used as an index of BRS. Results: Ang Ⅱ resulted in a significant decrease in the BRS for reflex bradycardia compared with control(-2.1±0.1 vs-3.9±0.4 beats·min -1·mmHg -1).Microinfusion of losartan had no significant effect on BRS for reflex bradycardia.The effect of Ang Ⅱ was almost completely abolished by pretreatment with microinjection of losartan. Conclusion:These results showed that the exogenous Ang Ⅱ in the RVLM produces inhibitory modulation of BRS,which is mediated by AT_1 receptor.However,AT_1 receptor in the RVLM is not involved in the tonic control of BRS. 展开更多
关键词 angiotensin AT_1 receptor baroreceptor reflex rostral ventralateral medulla
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Dynamic fracture behavior of rock under impact load using the caustics method 被引量:7
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作者 YANG Ren-shu YUE Zhong-wen +2 位作者 SUN Zhong-hui XIAO Tong-she GUO Dong-ming 《Mining Science and Technology》 EI CAS 2009年第1期79-83,共5页
We studied the dynamic fracture mechanical behavior of rock under different impact rates. The fracture experiment was a three-point bending beam subjected to different impact loads monitored using the reflected causti... We studied the dynamic fracture mechanical behavior of rock under different impact rates. The fracture experiment was a three-point bending beam subjected to different impact loads monitored using the reflected caustics method. The mechanical parameters for fracture of the three-poim bending beam specimen under impact load are analyzed. The mechanism of crack propagation is discussed. Experimental results show that the dynamic stress intensity factor increases before crack initiation. When the dynamic stress intensity factor reaches its maximum value the crack starts to develop. After crack initiation the dynamic stress intensity factor decreases rapidly and oscillates. As the impact rate increases the cracks initiate earlier, the maximum value of crack growth velocity becomes smaller and the values of dynamic stress intensity factor also vary less during crack propagation. The results provide a theoretical basis for the study of rock dynamic fracture. 展开更多
关键词 ROCK impact load reflected caustics dynamic stress intensity factor crack extension regularity
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Hysteresis of saturation-capillary pressure relations under consecutive drainage-imbibition cycles in fine sandy medium
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作者 XIE Xiao-xi LI Yan +3 位作者 XIA Bei-cheng XU Li-min SU Yu GU Qing-bao 《Journal of Central South University》 SCIE EI CAS 2012年第1期222-230,共9页
The hysteresis of saturation-capillary pressure (S-p) relations was investigated in a fine sandy medium under consecutive drainage-imbibition cycles, which resulted from scheduled water level fluctuations. A drainag... The hysteresis of saturation-capillary pressure (S-p) relations was investigated in a fine sandy medium under consecutive drainage-imbibition cycles, which resulted from scheduled water level fluctuations. A drainage-imbibition cycle starts with a drainage process and ends with an imbibition process in sequence. The saturation and capillary pressure were measured online with time domain reflectometry (TDR) probes and T5 tensiometers, respectively. Results show that the relation between the degree of hysteresis and the number of the drainage-imbibition cycles is not obvious. However, the degree decreases with the increase of the initial water saturation of the imbibition processes in these drainage-imbibition cycles. The air-entry pressure of a sandy medium is also found to be constant, which is independent of the drainage-imbibition cycles and the initial water saturation of the drainage process. In all the imbibition processes, parameter a of the van Genuchten (VG) model decreases with the increase of the initial water saturation, which corresponds positively to the magnitude of the hysteresis. 展开更多
关键词 S-p relation HYSTERESIS drainage IMBIBITION van Genuchten model
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我国路标涂料前景光明
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《宁夏石油化工》 2003年第3期58-58,共1页
关键词 中国 路标涂料 产品质量 产量 干燥时间 反射
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Piezoelectric responses of brittle rock mass containing quartz to static stress and exploding stress wave respectively 被引量:1
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作者 万国香 李夕兵 洪亮 《Journal of Central South University of Technology》 EI 2008年第3期344-349,共6页
The electromagnetic emission(EME) induced from the rock containing piezoelectric materials was investigated under both static stress and exploding stress wave in the view of piezoelectric effect. The results show that... The electromagnetic emission(EME) induced from the rock containing piezoelectric materials was investigated under both static stress and exploding stress wave in the view of piezoelectric effect. The results show that the intensity of the EME induced from the rock under static stress increases with increasing stress level and loading rate; the relationship between the amplitude of the EME from the rock under different modes of stress wave and elastic parameters and propagation distance was presented. The intensity of the EME relates not only to the strength and elastic moduli of rock masses,but also to the initial damage of the rock. The intensity of EME induced by stress wave reaches the highest at the explosion-center and attenuates with the propagation distance. The intensity of EME increases with increasing the elastic modulus and decreases with increasing initial damage. The results are in good agreement with the experimental results. 展开更多
关键词 piezoelectric responses electromagnetic emission static stress exploding stress wave
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Laser Ablation Atomic Beam Apparatus with Time-Sliced Velocity Map Imaging for Studying State-to-State Metal Reaction Dynamics
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作者 董常武 刘嘉兴 +1 位作者 李芳芳 王凤燕 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第1期99-104,I0002,共7页
We report a newly constructed laser ablation crossed molecular beam apparatus, equipped with time-sliced velocity map imaging technique, to study state-to-state metal atom reaction dynamics. Supersonic metal atomic be... We report a newly constructed laser ablation crossed molecular beam apparatus, equipped with time-sliced velocity map imaging technique, to study state-to-state metal atom reaction dynamics. Supersonic metal atomic beam is generated by laser vaporization of metal rod, and free expansion design without gas flow channel has been employed to obtain a good quality of metal atomic beam. We have chosen the crossed-beam reaction Al+O2 to test the performance of the new apparatus. Two-rotational-states selected AIO(X^2∑+, v=0, N and N+I4) products can be imaged via P(N) and R(N+14) branches of the Av=l band at the same wavelength, during (1+1) resonance-enhanced multi-photon ionization through the AIO(D2E+) intermediate state. In our experiment at 244.145 nm for simultaneous transitions of P(15) and R(29) branch, two rings in slice image were clearly distinguishable, corresponding to the AiO(v=0, N=IS) and AIO(v=0, N=29) states respectively. The energy difference between the two rotational levels is 403 cm^-1. The success of two states resolved in our apparatus suggests a better collisional energy resolution compared with the recent research study [J. Chem. Phys. 140, 214304 (2014)]. 展开更多
关键词 Time-sliced velocity map imaging Crossed beam Laser ablation Metal atom reaction dynamics
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Differential Cross Sections and Collision-Induced Rotational Alignment in Inelastic Scattering of NO(X)by Xe
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作者 Mark Brouard Helen Chadwick +6 位作者 Sean DSGordon Cornelia GHeid Balazs Hornung Bethan Nichols Jacek Klos Pablo GJambrina FJavier Aoiz 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第2期217-233,I0003,J0001-J0017,共35页
Fully A-doublet resolved differential cross sections and collision-induced rotational alignment moments have been measured for the NO(X)-Xe collision system at a collision energy of 519 cm^-1.The experiments combine i... Fully A-doublet resolved differential cross sections and collision-induced rotational alignment moments have been measured for the NO(X)-Xe collision system at a collision energy of 519 cm^-1.The experiments combine initial quantum state selection,employing a hexapole inhomogeneous electric field,with quantum state resolved detection,using(1+1')resonantly enhanced multiphoton ionization and velocity map ion imaging.The differential cross sections and polarization dependent differential cross sections are shown to agree well with quantum mechanical scattering calculations performed on ab initio potential energy surfaces[J.Klos et al.J.Chem.Phys.137,014312(2012)].By comparison with quasi-classical trajectory calculations,quantum mechanical scattering calculations on a hard-shell potential,and kinematic apse model calculations,the effects of the attractive part of the potential on the measured differential cross sections and collision-induced rotational alignment moments are assessed. 展开更多
关键词 Chemical Physics Reaction dynamics Inelastic scattering
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灯罩的选购
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《山东农机化》 1996年第9期20-20,共1页
选购灯罩,首先要考虑用途。白色玻璃罩透光性能好,适于看书写字;彩色玻璃灯罩透光性能差,适用于改变环境色调;纱灯罩使灯光散发出来后变得柔和均匀,是理想书写灯罩;
关键词 灯罩 透光性能 彩色玻璃 纱灯 色灯 改变环境 散发出 反射 色调 吸收
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FORMATION OF LARGE-SCALE TECTONIC ELEMENTS FROM THE POSITION OF CENTRIFUGAL-INERTIAL FORCE ACTION
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作者 Molchanov V. I. Paraev V. V. 《Geotectonica et Metallogenia》 2005年第1期13-33,共21页
We describe the earlier unknown, when applied to global tectonics, centrifugal inertial mechanism of lithosphere plate moving under the effect of forces appearing as a result of Earth’s planetary rotation. The mechan... We describe the earlier unknown, when applied to global tectonics, centrifugal inertial mechanism of lithosphere plate moving under the effect of forces appearing as a result of Earth’s planetary rotation. The mechanism stated gives an insight into global tectonics of plates with the indirect participation of emanation streams which, in their turn, are the derivatives of centrifugal and inertial forces of planetary motion. The application of this mechanism provides a logical explanation for the regularities of global tectogenesis including the formation of mountain ridges mainly of submeridional and sublatitudinal strike, and also the drift of continental plates from the east to the west and from the south to the north. The mechanism clarifies the significance of the Arctic and the Antarctic Circles as geodynamic barriers. 展开更多
关键词 formation tectonic element centrifugal-inertial force section
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Water blocking effect caused by the use of hydraulic methods for permeability enhancement in coal seams and methods for its removal 被引量:9
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作者 Liu Qian Guo Yusen +2 位作者 An Fenghua Lin Luyao Lai Yongming 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期615-621,共7页
To research techniques for removing the water blocking effect caused by hydraulic applications in coal seams,the use of surfactants is proposed,based on the mechanics of the water blocking effect.Centrifugal experimen... To research techniques for removing the water blocking effect caused by hydraulic applications in coal seams,the use of surfactants is proposed,based on the mechanics of the water blocking effect.Centrifugal experiments were used to validate the effects of using surfactants;the results show that after dealing with vacuum saturation with water,the volume of micropores decreases,which results in a larger average pore size,and the volume of transitional pores,mesopores,macropores and total pores increases.Based on the distribution of pore size,the operation mode of ‘‘water infusion after gas extraction,then continuing gas extraction" is recommended to improve the volume of coal mine gas drainage.When the reflectance of vitrinite in coal samples is less than 1,using the surfactants Fast T,1631,APG,BS can mitigate the damage caused by the water blocking effect.But when the reflectance of vitrinite is larger than 1.4,the damage caused by the water blocking effect can be increased.When the surfactant CMC is used in hydraulic applications,the capillary forces of coal samples are almost negative,which means the capillary force is in the same direction as the gas extraction.The direction of capillary forces benefits the gas flow.So,using CMC can play an active role in removing the water blocking effect.Centrifugal experiments confirm that using CMC can effectively remove the water blocking effect,which has a beneficial effect on improving the gas drainage volume. 展开更多
关键词 Gas extraction Hydraulic measures Water blocking effect Capillary force Surfactant
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