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断裂带的动力分异和化合 被引量:3
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作者 张治洮 《地球化学》 CAS 1983年第1期62-70,110-111,共11页
Chemical compositional changes in fault zones are dealt with in this paper from a dynamic point of view. In fault zones consisted of silicates, relative accumulation of Si and Fe is noticed in response to the leaching... Chemical compositional changes in fault zones are dealt with in this paper from a dynamic point of view. In fault zones consisted of silicates, relative accumulation of Si and Fe is noticed in response to the leaching of K, Na, and to a lesser extent, Mg,Ca and Ah The order of pctrogenetic elements from stable to mobile is tentatively suggested as follows: Si, Fe, Mg, Ca, Al, K and Na. The difference in ionic radius of these chemical elements is thought; to be the major factor controlling this dynamic differentiation. For fault zones along which one side is silicates and the other is carbonates, new mincrals are recognized in tectonite. On the silicate side Ca and Mg increase but Si and Al decrease; and the reverse is true on the carbonate side. This phenomenon indicates that the migration of elements in fault; zones is accelerated by dynamic cffect. 展开更多
关键词 断裂带 动力分异 动力化合 化学成
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新城-黄陂走滑韧性剪切带的动力分异作用 被引量:4
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作者 谭秋明 刘忠明 《大地构造与成矿学》 EI CAS CSCD 1995年第2期171-177,共7页
本文通过对新城-黄陂断裂带中合河-殷店右行走滑韧性剪切带内糜棱岩类岩石化学成分、稀土元素及微量元素随Ss-Sc夹角和古差异应力(△δ)的变化梯度的研究,初步探讨了右行走滑韧性剪切带的动力分异作用。
关键词 走滑 剪切带 糜棱岩 动力分异 岩石化学
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中国三大城市化区域劳动力市场结构分割研究 被引量:6
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作者 徐伟 宁越敏 《世界地理研究》 北大核心 2009年第2期1-15,共15页
本文考察了长三角、珠三角和京津唐三大城市化区域的中国劳动力市场空间与结构类型。基于劳动力市场分异和分割理论,本研究利用全国综合社会调查数据显示了研究区域内劳动力市场分异分割存在的大量证据。劳动力市场以性别、户口性质、... 本文考察了长三角、珠三角和京津唐三大城市化区域的中国劳动力市场空间与结构类型。基于劳动力市场分异和分割理论,本研究利用全国综合社会调查数据显示了研究区域内劳动力市场分异分割存在的大量证据。劳动力市场以性别、户口性质、企业所有制等为分异轴线的特征十分明显。文章还进一步指出了中国劳动力市场不仅是由劳动力的供求市场关系来塑造,同时也受制于各种制度性因素的作用。人力资本因素如教育等虽然是中国劳动市场分异的重要因素,但户口等制度性要素仍然严重地塑造着劳动力市场的分割。 展开更多
关键词 动力 动力市场 动力市场 收入 三大城市化区域
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福州地热田人工补给深循环热交换机理分析 被引量:2
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作者 赵钦铭 《福建地质》 1991年第3期220-246,共27页
根据花岗岩裂隙型热储的构造条件,以及冷热水温差所引起的重力分异驱动力、注水水柱压力和水柱向下运动的惯性冲力等原理,采用热中心近距离强迫对流深循环热交换新技术,把约17℃的冷水加温成90℃左右的热水,促使地下水位大幅度回升。通... 根据花岗岩裂隙型热储的构造条件,以及冷热水温差所引起的重力分异驱动力、注水水柱压力和水柱向下运动的惯性冲力等原理,采用热中心近距离强迫对流深循环热交换新技术,把约17℃的冷水加温成90℃左右的热水,促使地下水位大幅度回升。通过三次对比试验,取得圆满结果。该成果普遍适甩于以陡倾断层裂隙为热储的地热田人工补给回灌,它是解决这类热田地下热水资源不足的最经济方法之一。通过三次回灌对比试验,证明采用人工补给深循环热交换技术具有升温快、回收率高及水位回升大等优点,因此它是增大地热田的开采量、促使地下水位回升、防止地面下沉、改善水质等促使地热田“复生”,防止衰退的可靠保护措施。其经济效益、社会环境效益显著,且有利于改善福州市区对外开放的投资环境。同时,对沿海咸水温泉带及西藏、云南高温高矿化地热带的开发利用、设备的防腐蚀、防结垢及防止开采井堵塞等也具有一定的推广应用价值。 展开更多
关键词 地热田 人工补给 热交换 重力动力
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亦论韧性剪切变形与金的成矿作用——与邵世才《试论韧性剪切变形与金的成矿》一文的讨论 被引量:20
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作者 陈柏林 李中坚 董法先 《贵金属地质》 1998年第3期228-232,共5页
剪切带型金矿是一种重要的金矿类型.韧性-超韧性深层次剪切变形是促使Au元素活化分异、形成动力变质含金热液的过程,中浅层次的韧脆性、脆性剪切变形区是Au元素聚集成矿部位.韧脆性剪切带的不同变形层次及其构造岩类型决定了剪... 剪切带型金矿是一种重要的金矿类型.韧性-超韧性深层次剪切变形是促使Au元素活化分异、形成动力变质含金热液的过程,中浅层次的韧脆性、脆性剪切变形区是Au元素聚集成矿部位.韧脆性剪切带的不同变形层次及其构造岩类型决定了剪切带型金矿床的矿化类型.剪切带型金矿床往往具有成矿时代滞后、空间规模差异、物源指示差异、韧性变形强度与Au元素含量反相关等异常特征.长期演化的造山带附近及边缘是寻找大型剪切带型金矿床的有利地区. 展开更多
关键词 韧性剪切带 金矿床 成矿作用 动力分异 热液成矿
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滑脱构造与铀矿化——以巴西Lagoa Real和华南661铀矿床为例 被引量:1
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作者 刘继顺 《矿产与地质》 1991年第6期447-452,共6页
分析研究滑脱构造基本特征及其有关铀矿床成矿作用.发现逆冲或滑脱过程中的高温高压和异常高孔隙液压环境,能够促使铀的大规模活化迁移和含铀溶液的形成,因而对铀成矿起了积极作用,滑脱构造带是华南地区找铀的构造标志,尤其应注意在前... 分析研究滑脱构造基本特征及其有关铀矿床成矿作用.发现逆冲或滑脱过程中的高温高压和异常高孔隙液压环境,能够促使铀的大规模活化迁移和含铀溶液的形成,因而对铀成矿起了积极作用,滑脱构造带是华南地区找铀的构造标志,尤其应注意在前震旦系逆冲或滑覆到上震旦至下寒武统的地段找铀. 展开更多
关键词 滑脱构造 铀矿 矿化 动力分异 矿床
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循环累积因果机制与我国区域协调发展 被引量:9
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作者 安虎森 蒲业潇 《华中师范大学学报(人文社会科学版)》 CSSCI 北大核心 2010年第3期36-41,共6页
改革开放以来,我国经济逐渐在沿海地区集聚,沿海与内陆地区人均收入差距也逐渐拉大。本文认为,我国目前的经济活动高度聚集在沿海地区,是地理优势和政策优势促使下形成循环累积过程的必然结果,主要表现为沿海地区工业部门不断吸纳内陆... 改革开放以来,我国经济逐渐在沿海地区集聚,沿海与内陆地区人均收入差距也逐渐拉大。本文认为,我国目前的经济活动高度聚集在沿海地区,是地理优势和政策优势促使下形成循环累积过程的必然结果,主要表现为沿海地区工业部门不断吸纳内陆地区劳动力的过程,也表现为不断吸纳高学历、高技能人才的过程。在此基础上,提出了旨在实现区域协调发展的促进劳动力自由流动、扩大一般性转移支付、改革资源税、鼓励高学历人才到内陆地区创业等政策性建议。 展开更多
关键词 经济活动空间聚集 循环累积因果机制 动力的区际 区域协调发展
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湖北慈口—富水地区地质构造特征及金构造地球化学
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作者 谭秋明 柯云峰 黎湘 《湖北地质》 1992年第2期75-86,共12页
慈口—富水一带的金异常和金矿化是受慈口—富水双冲式逆掩断裂带控制的;运用极射赤平投影法,恢复本区曾经历了五期构造运动及其构造应力场;运用构造地球化学的理论和研究方法,探讨了逆掩断裂带的功热转换、元素迁移富集及金富集的最佳... 慈口—富水一带的金异常和金矿化是受慈口—富水双冲式逆掩断裂带控制的;运用极射赤平投影法,恢复本区曾经历了五期构造运动及其构造应力场;运用构造地球化学的理论和研究方法,探讨了逆掩断裂带的功热转换、元素迁移富集及金富集的最佳构造部位;探讨了热液通道及迁移方向;提出了构造控矿模式。 展开更多
关键词 双冲式逆掩断裂带 动力分异 动热变质 构造地球化学 热液中心通道
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Anisotropy of Thermal-expansion for β-Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine: Quantum Chemistry Calculation and Molecular Dynamics Simulation
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作者 钱文 张朝阳 +3 位作者 舒远杰 熊鹰 宗和厚 张伟斌 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第1期57-62,I0003,共7页
Molecular dynamics simulations on octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) at 303-383 K and atmospheric pressure are carried out under NPT ensemble and COMPASS force field, the equilibrium structures a... Molecular dynamics simulations on octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) at 303-383 K and atmospheric pressure are carried out under NPT ensemble and COMPASS force field, the equilibrium structures at elevated temperatures were obtained and showed that the stacking style of molecules don't change. The coefficient of thermal expansion (CTE) values were calculated by linear fitting method. The results show that the CTE values are close to the experimental results and show anisotropy. The total energies of HMX cells with separately increasing expansion rates (100%-105%) along each crystallographic axis was calculated by periodic density functional theory method, the results of the energy change rates are anisotropic, and the correlation equations of energy change-CTE values are established. Thus the hypostasis of the anisotropy of HMX crystal's thermal expansion, the determinate molecular packing style, is elucidated. 展开更多
关键词 Octahydro-1 3 5 7-tetranitro-1 3 5 7-tetrazocine Molecular dynamics simula-tion Thermal expansion ANISOTROPY Density functional theory
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Clinical analysis of propofol deep sedation for 1,104 patients undergoing gastrointestinal endoscopic procedures:A three year prospective study 被引量:42
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作者 Stojanka Gaparovi Nadan Rustemovi +4 位作者 Milorad Opai Marina Premuzi Andelko Korui Jadranka Bozikov Tamara Bates 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第2期327-330,共4页
AIM: To analyze the hemodynamic and respiratory effects of propofol on patients undergoing gastroscopy and colonoscopy. METHODS: In this prospective study, conducted over a period of three years, 1,104 patients refe... AIM: To analyze the hemodynamic and respiratory effects of propofol on patients undergoing gastroscopy and colonoscopy. METHODS: In this prospective study, conducted over a period of three years, 1,104 patients referred for a same day GI endoscopy procedure were analyzed. All patients were given a propofol bolus (0.5-1.5 mg/kg). Arterial blood pressure (BP) was monitored at 3 rain intervals and heart rate and oxygen saturation (SpO2) were recorded continuously by pulse oximetry. Analyzed data acquisition was carried out before, during, and after the procedure. RESULTS: A statistically significant reduction in mean arterial pressure was demonstrated (P〈0.001) when compared to pre-intervention values, but severe hypotension, defined as a systolic blood pressure below 60mmHg, was noted in only 5 patients (0.5%). Oxygen saturation decreased from 96.5% to 94.4 % (P〈0.001). A critical decrease in oxygen saturation (〈90%) was documented in 27 patients (2.4%). CONCLUSION: Our results showed that propofol provided good sedation with excellent pain control, a short recovery time and no significant hemodynamic side effelts if carefully titrated. All the patients (and especially ASA Ⅲ group) require monitoring and care of an anesthesiologist. 展开更多
关键词 ENDOSCOPY Conscious sedation PROPOFOL Hemodynamic adverse effects
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Molecular dynamics simulation on mechanisms of plastic anisotropy in nanotwinned polycrystalline copper with{111}texture during tensile deformation 被引量:5
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作者 Yan-qiu ZHANG Shu-yong JIANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第5期1381-1396,共16页
Based on molecular dynamics(MD)simulation,the mechanisms of plastic anisotropy in nanotwinned polycrystalline copper with{111}texture during tensile deformation were systematically studied from the aspects of Schmid f... Based on molecular dynamics(MD)simulation,the mechanisms of plastic anisotropy in nanotwinned polycrystalline copper with{111}texture during tensile deformation were systematically studied from the aspects of Schmid factor of the dominant slip system and the dislocation mechanism.The results show that the Schmid factor of dominated slip system is altered by changing the inclining angle of the twin boundaries(TBs),while the yield stress or flow stress does not strictly follow the Schmid law.There exist hard and soft orientations involving different dislocation mechanisms during the tensile deformation.The strengthening mechanism of hard orientation lies in the fact that there exist interactions between the dislocations and the TBs during plastic deformation,which leads to the dislocation blocking and reactions.The softening mechanism of soft orientation lies in the fact that there is no interaction between the dislocations and the TBs because only the slip systems parallel to the TBs are activated and the dislocations slip on the planes parallel to the TBs.It is concluded that the plastic anisotropy in the nanotwinned polycrystalline copper with{111}texture is aroused by the combination effect of the Schmid factor of dominated slip system and the dislocation mechanism. 展开更多
关键词 mechanical property dislocations molecular dynamics plastic anisotropy NANOTWINS
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GPCR A2AAR Agonist Binding and Induced Conformation Changes of Functional Switches
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作者 庞雪芹 刘建勇 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第1期29-38,I0003,共11页
Agonist binding of A2A adenosine receptor (A2AAR) shows protective effects against inflammatory and immune. Efforts are exerted in understanding the general mechanism and developing A2AAR selectively binding agonist... Agonist binding of A2A adenosine receptor (A2AAR) shows protective effects against inflammatory and immune. Efforts are exerted in understanding the general mechanism and developing A2AAR selectively binding agonists. Using molecular dynamics (MD) simula- tions, we have studied the interactions between A2AAR and its agonist (adenosine), and analyzed the induced dynamic behaviors of the receptor. Key residues interacting with adenosine are identified: A63^2.61,I66^2.64,V84^3.32,L85^3.33,T88^3.36,F168^5.29,M177^5.38,L249^6.51,H250^6.52 and N253^6.55 interacting with adenosine with affinities larger than 0.5 kcal/mol. Moreover, no interaction between adenosine and L167^5.28 is observed, which supports our previous findings that L1675^5.28 is an antagonist specific binding reside. The dynamic be- haviors of agonist bound A2AAR are found to be different from apo-A2AAR in three typical functional switches: (i) tight "ionic lock" forms in adenosine-A2AAR, but it is in equilibrium between formation and breakage in apo-A2AAR; (ii) the "rotamer toggle switch", T88^3.36/F242^6.44/W246^6.48, adopted different rotameric conformations in adenosin-A2AAR and apo-A2AAR; (iii) adenosine-A2AAR has a flexible intracellular loop 2 (IC2) and s-helical IC3, while apo-A2AAR preferred s-helical IC2 and flexible IC3. Our results indicate that agonist binding induced different conformational rearrangements of these characteristic functional switches in adenosine-A2AAR and apo-A2AAR. 展开更多
关键词 A2A adenosine receptor Molecular dynamics ADENOSINE Specific binding Conformational dynamics Ionic lock Rotamer toggle switch Secondary structure
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Molecular Dynamics Simulation of Temperature-dependent Flexibility of Thermophilic Xylose Isomerase
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作者 Wei Xu Ping Cai +2 位作者 Ming Yan Lin Xu Ping-kai Ouyang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第5期467-472,I0001,共7页
The complex model of Thermus thermophilus xylose isomerase (TtXI) with D-xylose was constructed, and molecular dynamics (MD) simulations were carried out at 300 and 360 K for 10 ns by NAMD2.5. The radius of gyrati... The complex model of Thermus thermophilus xylose isomerase (TtXI) with D-xylose was constructed, and molecular dynamics (MD) simulations were carried out at 300 and 360 K for 10 ns by NAMD2.5. The radius of gyration (Rg), subunit interactions, and residue flexibility were analyzed. The results show that residues 60-69, 142-148, 169-172, and 332-340 have high flexibility at 300 and 360 K. Residues with higher flexibility at 360 K than that at 300 K can mainly be divided into two groups: one locates in the helix-loophelix region consisting of residues 55-80 in catalytic domain; the other at subunit interfaces. The Rg of catalytic domain at 360 K shows 0.16 A higher than that at 300 K, but Rg of small C-terminal domain has no obvious difference. The results indicate that enhanced Rg of catalytic domain may lead to the intense motion of the active site of TtXI and promote the D-xylose isomization reaction. Eight hydrogen bonds and five ion pairs are reduced at subunit interfaces at 360 K compared with 300 K, that may be the main reason for the decrease in rigidity and increase in activity at high temperature of TtXI. This result also help to explain the cold-adaption phenomenon of TtXI E372G mutant reported previously. Our results reveal the relationship between temperature and structure flexibility of TtXI, and play an important role in understanding the thermostability of thermophile protein with multiple subunits. 展开更多
关键词 Molecule dynamics Xylose isomerase Structure FLEXIBILITY
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Wave Interaction with Dual Circular Porous Plates 被引量:2
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作者 Arpita Mondal R. Gayen 《Journal of Marine Science and Application》 CSCD 2015年第4期366-375,共10页
In this paper we have investigated the reflection and the transmission of a system of two symmetric circular-arc-shaped thin porous plates submerged in deep water within the context of linear theory. The hypersingular... In this paper we have investigated the reflection and the transmission of a system of two symmetric circular-arc-shaped thin porous plates submerged in deep water within the context of linear theory. The hypersingular integral equation technique has been used to analyze the problem mathematically. The integral equations are formulated by applying Green's integral theorem to the fundamental potential function and the scattered potential function into a suitable fluid region, and then using the boundary condition on the porous plate surface. These are solved approximately using an expansion-cure-collocation method where the behaviour of the potential functions at the tips of the plates have been used. This method ultimately produces a very good numerical approximation for the reflection and the transmission coefficients and hydrodynamic force components. The numerical results are depicted graphically against the wave number for a variety of layouts of the arc. Some results are compared with known results for similar configurations of dual rigid plate systems available in the literature with good agreement. 展开更多
关键词 water wave scattering circular-arc-shaped plates hypersingular integral equation Green's integral theorem reflection coefficient energy identity hydrodynamic force
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Molecular dynamics simulations investigate the long-range effects on TrpR(tryptophan repressor protein)
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作者 FENG Xianli LIU Jia 《分子科学学报》 CAS 2024年第2期174-181,共8页
Molecular dynamics(MD)simulations and anisotropic thermal diffusion dynamics(ATD)simulations were performed on the wild TrpR and its 75 residue mutant(mTrpR)to investigate TrpR longrange effects.The ATD result shows t... Molecular dynamics(MD)simulations and anisotropic thermal diffusion dynamics(ATD)simulations were performed on the wild TrpR and its 75 residue mutant(mTrpR)to investigate TrpR longrange effects.The ATD result shows that the mTrpR has higher fluctuation than the wild TrpR,and its helix chainⅡF has particular disorder.It is obvious that the 75 residue of wild TrpR and mTrpR affects the protein dynamics flexibilities by the long-range effects.The ATD and MD both confirm that the differences in the size of side-chain and three-dimensional structures of two different 75 residues in the wild TrpR and mTrpR will spread to the entire protein by way of the long-range effects.Long-range effect affects the protein side chain interaction,conformational changes,flexibilities and secondary structures.Further,the ATD result also shows that each 75 residue of the symmetric homodimer has the same effect,and the two 75 residues have a positive correlation in long-range regulating processes.The residues 48,50,71,79 in chainⅠof wild TrpR and residues 45,72,80 in chainⅡof mTrpR play important roles in long-range interaction processes. 展开更多
关键词 MD ATD TrpR long-range effect
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Complex fields in heterogeneous materials under shock:modeling, simulation and analysis 被引量:5
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作者 AiGuo Xu GuangCai Zhang +1 位作者 YangJun Ying Cheng Wang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第5期27-75,共49页
In this mini-review we summarize the progress of modeling, simulation and analysis of shock responses of heterogeneous materials in our group in recent years. The basic methodology is as below. We first decompose the ... In this mini-review we summarize the progress of modeling, simulation and analysis of shock responses of heterogeneous materials in our group in recent years. The basic methodology is as below. We first decompose the problem into different scales. Construct/Choose a model according to the scale and main mechanisms working at that scale. Perform numerical simulations using the relatively mature schemes. The physical information is transferred between neighboring scales in such a way: The statistical information of results in smaller scale contributes to establishing the constitutive equation in larger one. Except for the microscopic Molecular Dynamics(MD) model, both the mesoscopic and macroscopic models can be further classified into two categories,solidic and fluidic models, respectively. The basic ideas and key techniques of the MD, material point method and discrete Boltzmann method are briefly reviewed. Among various schemes used in analyzing the complex fields and structures, the morphological analysis and the home-built software, GISO, are briefly introduced. New observations are summarized for scales from the larger to the smaller. 展开更多
关键词 complex fields heterogeneous material molecular dynamics material point method discrete Boltzmann model
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Ion specificity in NaCl solution confined in silicon nanochannels 被引量:1
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作者 QIU YingHua TAN QiYan +1 位作者 SI Wei CHEN YunFei 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第1期230-238,共9页
Ion specificity of Na+ and C1- ions for NaCI solution confined in silicon nanochannels is investigated with molecular dynamics (MD) simulations. The MD simulation results demonstrate that ion specificity for Na+ a... Ion specificity of Na+ and C1- ions for NaCI solution confined in silicon nanochannels is investigated with molecular dynamics (MD) simulations. The MD simulation results demonstrate that ion specificity for Na+ and C1- ions exhibits clearly in na- nochannels with high surface charge density. The two types of ions show different density distributions perpendicular to the channel surface due to the ion specificity when they act as countefions near negatively and positively charged surfaces, respec- tively. Both the two counterion distributions cannot be predicted by Poisson-Boltzmann equation within 0.75 nm near the sur- face. In addition, the ion specificity is also demonstrated through affecting the water density distributions. In the nanochannel with negatively charged surfaces, the presence of the Na+ ions reduces the number of water peaks in water density distribution profile. In comparison, when the C1- ions act as counterions near positively charged surfaces, they do not affect the number of the water peaks. Besides the influence on the water density distribution, ion specificity also exhibits through affecting the wa- ter molecule orientation in the adsorbed layer. It is found that C1- ions make the water molecules in the adsorbed layer align more orderly than Na~ ions do when the two types of ions act as the counterions near the positively and negatively charged surfaces with the same surface charge density. 展开更多
关键词 ion specificity molecular dynamics simulations NANOCHANNEL Poisson-Boltzmann equation electrical double layer
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