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海洋环境体系中放射性核素吸附-解吸迟滞机制研究 被引量:3
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作者 陈超 朱君 +4 位作者 石云峰 邓安嫦 刘团团 谢添 张艾明 《原子能科学技术》 EI CAS CSCD 北大核心 2019年第5期797-804,共8页
通过宏观吸附-解吸等温实验,系统研究了放射性核素^(110)Ag^m在海洋环境中表层沉积物上的吸附动力学过程及不同沉积物浓度和核素初始浓度条件下吸附-解吸迟滞机制(吸附不可逆性)。研究结果表明:Freundlich等温吸附模型可很好地描述^(110... 通过宏观吸附-解吸等温实验,系统研究了放射性核素^(110)Ag^m在海洋环境中表层沉积物上的吸附动力学过程及不同沉积物浓度和核素初始浓度条件下吸附-解吸迟滞机制(吸附不可逆性)。研究结果表明:Freundlich等温吸附模型可很好地描述^(110)Ag^m在海水沉积物上的吸附-解吸过程;^(110)Ag^m吸附速率开始很快(0~24 h),呈指数型增加,而后逐渐趋于平缓,体系达到吸附平衡;改变沉积物浓度会产生明显的固体浓度效应,即^(110)Ag^m吸附等温线随沉积物浓度的升高而显著下降。体系解吸迟滞性可用解吸迟滞系数(TII)和解吸滞后角量化表征,在沉积物浓度0.1~3.0 g/L范围内,解吸迟滞系数和解吸滞后角先增大后减小,不可逆程度与^(110)Ag^m在颗粒表面与吸附点位的结合方式及微小颗粒物相互作用团聚导致的吸附剂有效吸附表面和吸附点位减小有关;对于不同沉积物浓度吸附体系,随核素初始浓度的增加,解吸迟滞系数总体先降低后增加,体系解吸迟滞性呈先减小后增大的变化趋势,其主要受两方面因素控制:1)^(110)Ag^m分子在颗粒物表面与吸附点位的结合方式;2)在浓度梯度力作用下,^(110)Ag^m分子扩散吸附导致颗粒物微孔乃至超微孔隙结构发生形变,孔隙通道形变有效锁定了内表面吸附的^(110)Ag^m,无法解吸脱落从通道中扩散出来,从而使吸附体系表现出一定程度的解吸迟滞性。 展开更多
关键词 放射核素 吸附-解吸等温线 解吸迟滞 海洋环境 沉积物
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风沙土不同有机矿质复合体对磷的解吸特征影响 被引量:1
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作者 王而力 王嗣淇 邱素芬 《农业环境科学学报》 CAS CSCD 北大核心 2013年第4期741-747,共7页
采用平衡解吸法研究了风沙土不同有机矿质复合体对磷的解吸特征影响。结果表明,通过过氧化氢去除腐殖质后的风沙土磷的解吸比例(Dr=0.99)大幅度增加,解吸迟滞性指数(TⅡ=0.02)显著降低,有机矿质复合体是影响磷在风沙土上固持特征的重要... 采用平衡解吸法研究了风沙土不同有机矿质复合体对磷的解吸特征影响。结果表明,通过过氧化氢去除腐殖质后的风沙土磷的解吸比例(Dr=0.99)大幅度增加,解吸迟滞性指数(TⅡ=0.02)显著降低,有机矿质复合体是影响磷在风沙土上固持特征的重要因素;磷在钙键和铁铝键有机矿质复合体团聚结构微孔隙中引起的团聚体结构不可逆形变是导致磷解吸比例降低、解吸迟滞性指数增大的原因之一。铁铝键有机矿质复合体除对团聚体结构形成有重要影响外,还存在铁铝氧化物及水化氧化物对磷的配位吸附作用,因而铁铝键有机矿质复合体(Dr=0.35、TⅡ=0.44)比钙键有机矿质复合体(Dr=0.62、TⅡ=0.28)对磷的固持能力强得多;考查风沙土对磷的解吸特征不但要考虑腐殖质的含量,更要考虑腐殖质的复合形态,它也是影响风沙土磷解吸特征的重要因素。钙键有机矿质复合体、铁铝键有机矿质复合体携载的吸附态磷对上覆水体的释放通量可分别按其饱和吸附量62%和35%估算。 展开更多
关键词 风沙土 有机矿质复合体 解吸分配系数 最大解吸 解吸比例 解吸迟滞指数
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汝箕沟矿无烟煤瓦斯的吸附性能及流动规律分析
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作者 孟兴国 《神华科技》 2018年第9期32-35,60,共5页
无烟煤层赋存大量瓦斯,论文通过数值分析出无烟煤吸附/解吸性能及瓦斯在煤层流动的规律,汝箕沟露天矿助燃物为瓦斯,对火区发展提供了物料基础,为瓦斯抽采起到理论支撑。
关键词 赋存状态 吸附 解吸性 瓦斯流动
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几种树脂对柚苷的吸附作用研究 被引量:20
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作者 吴厚玖 焦必林 +5 位作者 王华 孙志高 汪晓红 唐忠海 蒋大斌 余恩惠 《食品与发酵工业》 CAS CSCD 北大核心 1997年第4期37-39,57,共4页
对5种大孔树脂进行了柚苷静态等温吸附、动态吸附、解吸和果皮柚苷提取液吸附试验。结果表明这五种树脂对柚苷的吸附和解吸性能良好,其中A、B、C3种树脂效果最佳,它们的单分子层的饱和吸附量分别是95.3mg/g,111.5mg/g和115.0mg... 对5种大孔树脂进行了柚苷静态等温吸附、动态吸附、解吸和果皮柚苷提取液吸附试验。结果表明这五种树脂对柚苷的吸附和解吸性能良好,其中A、B、C3种树脂效果最佳,它们的单分子层的饱和吸附量分别是95.3mg/g,111.5mg/g和115.0mg/g,对浓度1mg/ml柚苷的无泄漏吸附量分别是34.7mg/ml,32.8mg/ml和37.5mg/ml。只需要2~3倍床体积的95%乙醇即可全部洗脱柚苷。它们可用于柚苷的回收和提纯,以及抽和葡萄柚汁的脱苦。 展开更多
关键词 柚苷 树脂 吸附 解吸性 水果加工 果汁
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综合地质勘探方法在隧道勘察中的运用 被引量:8
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作者 尧林 彭小平 《中外公路》 北大核心 2012年第4期231-233,共3页
综合地质勘察方法主要包括遥感判释、工程地质调绘、综合物探,以及深、浅孔钻探等。结合工程实例,该文对综合地质勘察方法的工作流程以及实际效果进行了分析总结,准确查明了隧道地质情况及存在的众多不良地质问题,科学、合理地划分了围... 综合地质勘察方法主要包括遥感判释、工程地质调绘、综合物探,以及深、浅孔钻探等。结合工程实例,该文对综合地质勘察方法的工作流程以及实际效果进行了分析总结,准确查明了隧道地质情况及存在的众多不良地质问题,科学、合理地划分了围岩类别,为复杂地质条件下高速公路隧道勘察提供了经验。 展开更多
关键词 地质调绘 钻探 抽水 大极距高密度电法 解吸性瓦斯检测 围岩级别
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Dynamics of Nonlinear Waves in(2+1)-Dimensional Extended Boiti-Leon-Manna-Pempinelli Equation
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作者 SUN Junxiu WANG Yunhu 《应用数学》 北大核心 2024年第4期1103-1113,共11页
Based on the Hirota bilinear method,this study derived N-soliton solutions,breather solutions,lump solutions and interaction solutions for the(2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation.The dynamic... Based on the Hirota bilinear method,this study derived N-soliton solutions,breather solutions,lump solutions and interaction solutions for the(2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation.The dynamical characteristics of these solutions were displayed through graphical,particularly revealing fusion and ssion phenomena in the interaction of lump and the one-stripe soliton. 展开更多
关键词 Hirota bilinear method N-soliton solutions Breather solutions Lump solutions Interaction solutions (2+1)-dimensional extended Boiti-Leon-Manna-Pempinelli equation
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沁水盆地高阶煤煤层气开发再认识 被引量:11
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作者 田炜 王会涛 《天然气工业》 EI CAS CSCD 北大核心 2015年第6期117-123,共7页
近年来,中国的煤层气产业出现了徘徊不前的颓势,单井产量低、核心技术瓶颈没有突破是制约其发展的主要原因。为此以沁水盆地煤层气开发现状为依据,从资源的可动用性、勘探评价程序的合理性、煤层采出水与注入水的利弊、煤层气开发井型等... 近年来,中国的煤层气产业出现了徘徊不前的颓势,单井产量低、核心技术瓶颈没有突破是制约其发展的主要原因。为此以沁水盆地煤层气开发现状为依据,从资源的可动用性、勘探评价程序的合理性、煤层采出水与注入水的利弊、煤层气开发井型等4个方面对高阶煤煤层气开发进行了深入分析,并得到4点新认识:①我国煤层气资源评价的核心是可动用性;②煤层气资源动用的决定因素是"三性"(解吸性、扩散性和渗透性);不同区块"三性"指标的优劣有所不同,这也表明不同区域制约煤层气高产的主控因素各不相同,既有单因素的,也有多因素耦合的结果;③要辩证看待"水力压裂"对煤层的改造与伤害,针对煤层"三性"短板特性的改造方式是提高煤层气单井产量的关键;④水平井是煤层气田高效开发最重要的手段之一,需要针对不同煤岩特点开展井型与无污染完井方式联合攻关。 展开更多
关键词 煤层气开发 沁水盆地 解吸性 扩散系数 渗透率 水力压裂 仿树形水平井
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On the Existence of Periodic Solutions of a Class Nonlinear Differential Systems 被引量:1
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作者 李林 徐琛梅 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期69-77,共9页
One method to show the existence of ω-periodic system is given. This method is based on the ultimately boundedness of the solution of the systems. By using comparing theorem and discussing some one dimensional equati... One method to show the existence of ω-periodic system is given. This method is based on the ultimately boundedness of the solution of the systems. By using comparing theorem and discussing some one dimensional equations the main results are obtained. 展开更多
关键词 differential system periodic solutions BOUNDEDNESS
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Gas desorption characteristics of the high-rank intact coal and fractured coal 被引量:15
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作者 Lu Shouqing Cheng Yuanping +3 位作者 Qin Liming Li Wei Zhou Hongxing Guo Haijun 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第5期819-825,共7页
The objective of this work is to study the gas desorption characteristics of the high-rank intact coal and fractured coal.The gas adsorption,mercury porosimetry and gas desorption experiments were carried out in this ... The objective of this work is to study the gas desorption characteristics of the high-rank intact coal and fractured coal.The gas adsorption,mercury porosimetry and gas desorption experiments were carried out in this study.Then,the theories of thermodynamics,diffusion mechanism and desorption kinetics were used to estimate the gas desorption characteristics.The results of gas adsorption experiments show that the initial isosteric adsorption heat of the intact coal is greater than that of the fractured coal,indicating that the gas molecules desorb more easily from fractured coal than intact coal.Using the mercury porosimetry,we find that the diffusion channels of fractured coal are more developed than those of intact coal.The difficult diffusion form dominates in the intact coal during the gas diffusing,while the easy diffusion form dominates in the fractured coal.The results of gas desorption experiments show that the initial gas desorption volume and velocity of the fractured coal are both greater than those of the intact coal.Using the Fick diffusion law,the study calculates the gas diffusion coefficients of the intact coal and fractured coal.The diffusion coefficients of the fractured coal are 2 times and 10 times greater than those of the intact coal at the time of 0-120 and 0-10 min,respectively. 展开更多
关键词 Intact coal Fractured coal Isosteric adsorption heat Diffusion coefficient
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Effect of an electrostatic field on gas adsorption and diffusion in tectonic coal 被引量:4
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作者 Jian Kuo Lei Dongji +2 位作者 Fu Xuehai Zhang Yugui Li Hengle 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第4期607-613,共7页
The characteristics of adsorption, desorption, and diffusion of gas in tectonic coal are important for the prediction of coal and gas outbursts. Three types of coal samples, of which both metamorphic grade and degree ... The characteristics of adsorption, desorption, and diffusion of gas in tectonic coal are important for the prediction of coal and gas outbursts. Three types of coal samples, of which both metamorphic grade and degree of damage is different, were selected from Tongchun, Qilin, and Pingdingshan mines. Using a series of experiments in an electrostatic field, we analyzed the characteristics of gas adsorption and diffusion in tectonic coal. We found that gas adsorption in coal conforms to the Langmuir equation in an electrostatic field. Both the depth of the adsorption potential well and the coal molecular electroneg- ativity increases under the action of an electrostatic field. A Joule heating effect was caused by changing the coal-gas system conductivity in an electrostatic field. The quantity of gas adsorbed and AP result from competition between the depth of the adsorption potential well, the coal molecular electronegativ- ity, and the Joule heating effect. △P peaks when the three factors control behavior equally. Compared with anthracite, the impact of the electrostatic field on the gas diffusion capacity of middle and high rank coals is greater. Compared with the original coal, the gas adsorption quantity,△P, and the gas diffusion capacity of tectonic coal are greater in an electrostatic field. In addition, the smaller the particle size of tectonic coal, the larger the△P. 展开更多
关键词 Electrostatic field Tectonic coal Depth of adsorption potential well Joule heating effect Initial velocity of gas diffusion
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Kinetic characteristics of coal gas desorption based on the pulsating injection 被引量:4
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作者 Ni Guanhua Lin Baiquan +3 位作者 Zhai Cheng Li Quangui Peng Shen Li Xianzhong 《International Journal of Mining Science and Technology》 SCIE EI 2014年第5期631-636,共6页
In order to understand the kinetic characteristics of coal gas desorption based on the pulsating injection (PI), the research experimentally studied the kinetic process of methane desorption in terms of the PI and h... In order to understand the kinetic characteristics of coal gas desorption based on the pulsating injection (PI), the research experimentally studied the kinetic process of methane desorption in terms of the PI and hydrostatic injection (HI). The results show that the kinetic curves of methane desorption based on PI and HI are consistent with each other, and the diffusion model can best describe the characteristics of meth- ane desorption. Initial velocity, diffusion capacity and ultimate desorption amount of methane desorption after P! are greater than those after HI, and the ultimate desorption amount increases by 16.7-39.7%. Methane decay rate over the time is less than that of the HI. The PI influences the diffusion model param- eters, and it makes the mass transfer Biot number B'_i decrease and the mass transfer Fourier series F'_0 increase. As a result, PI makes the methane diffusion resistance in the coal smaller, methane diffusion rate greater, mass transfer velocity faster and the disturbance range of methane concentration wider than HI. Therefore, the effect of methane desorption based on PI is better than that of HI. 展开更多
关键词 Pulsating injection Hydrostatic injection Methane desorption Kinetic characteristics
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VASCULAR ENDOTHELIAL INJURIES AND CHANGES OF BLOOD COAGULATION AND FIBRINOLYSIS INDEXES IN PATIENTS WITH ACUTE RESPIRATORY DISTRESS SYNDROME 被引量:4
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作者 Xiao-linHe ZhiLiu Shu-yueXia 《Chinese Medical Sciences Journal》 CAS CSCD 2004年第4期252-256,共5页
Objective To study endothelial damage by observing changes of circulating endothelial cells (CECs) in blood, coagula-tion and fibrinolysis index in patients with acute respiratory distress syndrome. Methods CECs were ... Objective To study endothelial damage by observing changes of circulating endothelial cells (CECs) in blood, coagula-tion and fibrinolysis index in patients with acute respiratory distress syndrome. Methods CECs were separated by isopycnic centrifugation method in 14 patients with acute lung injury (ALI), 7 patients with acute respiratory distress syndrome (ARDS), 10 intensive care unit (ICU) controls, and 15 healthy controls. Plasma prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FG), fibrin degradation products (FDP), and D-dimer were examined simultaneously. Acute physiology and chronic health evaluation (APACHE)Ⅱand lung injury score (LIS) were recorded to evaluate severity of illness and lung injury. Results (1) The number of CECs in ALI (10.4 ±2.3) and ARDS groups (16.1 ±2.7) was higher than that in the healthy (1.9 ±0.5) (P< 0.01). In both ALI and ARDS, the number of CECs correlated with APACHEⅡ(r=0.55, P< 0.05 and r=0.62, P< 0.05, respectively)and LIS (r=0.60, P< 0.05 and r=0.53, P< 0.05, respectively). CEC number was negatively correlated with PaO 2 in ALI and ARDS (r=-0.49, P< 0.05 and r=-0.64, P< 0.05, respectively). (2) The level of FDP and D-dimer were higher in ALI and ARDS patients than that in ICU and healthy control groups (P< 0.05). The level of FG in ARDS group was significantly higher than in the ICU and healthy control groups (P< 0.05). But in ALI group, the level of FG was significantly higher than only healthy control group (P< 0.05). Conclusions Endothelial cell damage occurs in ARDS patients, which may play a major role in the pathophysiology of ARDS. Changes of endothelial cell activation and damage markers, such as CECs, plasma coagulation and fibrinolysis index, to some extent reflect severity of illness and lung injury in ARDS. 展开更多
关键词 acute respiratory distress syndrome endothelial cell FIBRINOGEN FIBRIN D-DIMER
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Global Attractors of Strong Solution for the Generalized Kuramoto-Sivashinsky Equation
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作者 王素云 牟录贵 张艳红 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第1期75-82,共8页
Using a new method developed in [5], we prove the existence of global attractors for the Generalized Kuramoto-Sivashinsky equation in H^3per(Ω) and H^4per(Ω).
关键词 generalized Kuramoto-Sivashinsky equation strong solution global attractor
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