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反褶积分层解释的判别因子分析方法 被引量:2
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作者 秦积庚 《物探化探计算技术》 CAS CSCD 1991年第3期185-195,共11页
本文叙述了自然伽玛测井中反褶积分层解释法的原理及方法,并对影响解释精度的各种干扰因素进行了充分的讨论,特别是对如何有效地选择最佳特征参数α值而导出的判别因子法作了详细的论述,给出了推导公式,提供了模型和实测数据,并给出了... 本文叙述了自然伽玛测井中反褶积分层解释法的原理及方法,并对影响解释精度的各种干扰因素进行了充分的讨论,特别是对如何有效地选择最佳特征参数α值而导出的判别因子法作了详细的论述,给出了推导公式,提供了模型和实测数据,并给出了判别因子解释程序和应用实例。 展开更多
关键词 测井 反褶积 分层解 判别因子
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分层解堵工艺在西区采油厂注水井中的应用探究
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作者 韩阿维 李林 李东海 《石化技术》 CAS 2016年第8期155-155,168,共2页
主要阐述对注水井开展分层解堵工艺的必要性,分析注水井堵塞的原因,并根据堵塞原因阐述分层解堵的机理,讲述采用分层解堵工艺操作的现场作业流程,旨在不断提高西区采油厂注水井的开采效率。
关键词 西区采油厂 注水井 分层解堵工艺
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巧用“分层解疑法组合文章主题思想”方法阅读文章漫谈
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作者 徐德仁 《成才之路》 2020年第23期34-35,共2页
在语文阅读学习中,不少学生在阅读过程中存在不理解文章主题思想的问题,严重影响了阅读效果。教师在记叙文、说明文、议论文的阅读教学过程中运用“分层解疑法组合文章主题思想”方法,可以激发学生对阅读学习的积极性,提高学生的阅读水... 在语文阅读学习中,不少学生在阅读过程中存在不理解文章主题思想的问题,严重影响了阅读效果。教师在记叙文、说明文、议论文的阅读教学过程中运用“分层解疑法组合文章主题思想”方法,可以激发学生对阅读学习的积极性,提高学生的阅读水平。文章对“分层解疑法组合文章主题思想”方法在阅读教学中的有效运用进行探讨。 展开更多
关键词 语文 阅读教学 分层解疑法 主题思想 阅读水平
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N,N-二甲基乙酰胺溶胀解离回收碳纤维增强环氧树脂复合材料
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作者 李展 邢明飞 +1 位作者 李紫鑫 董丽丽 《工程塑料应用》 CAS CSCD 北大核心 2023年第4期7-12,共6页
碳纤维增强树脂基复合材料(CFRP)中的脆性玻璃态环氧树脂会将碳纤维紧密包裹,导致机械回收法获得的粉末或短纤维利用价值较低。针对这一难题,通过树脂溶胀原理将CFRP中的玻璃态环氧树脂转变为高弹态环氧树脂,显著改善了CFRP的力学解离... 碳纤维增强树脂基复合材料(CFRP)中的脆性玻璃态环氧树脂会将碳纤维紧密包裹,导致机械回收法获得的粉末或短纤维利用价值较低。针对这一难题,通过树脂溶胀原理将CFRP中的玻璃态环氧树脂转变为高弹态环氧树脂,显著改善了CFRP的力学解离性能。结果表明,CFRP中的环氧树脂可以在120~160℃的N,N-二甲基乙酰胺(DMAC)中快速溶胀,对应溶胀率为51.57%~59.71%。因溶胀作用环氧树脂基体过度膨胀和碎裂,导致CFRP解离为易于机械裁切的碳纤维薄层。碳纤维薄层通过裁切、烘干、热压成型工艺被重新制备成力学性能优异的CFRP。新制备的CFRP弯曲强度可达到原始CFRP板的76.38%~90.98%。同时DMAC化学性质稳定,可循环回收利用。 展开更多
关键词 碳纤维复合材料 树脂溶胀 分层解 N N-二甲基乙酰胺 资源化
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针刀分层松解术治疗风湿性多肌痛1例
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作者 高超 《光明中医》 2022年第1期139-141,共3页
风湿性多肌痛以肩胛带及骨盆带的肌肉疼痛、关节受限为主要症状表现,目前指南主要以口服激素为主要治疗方案,不良作用明显。针刀分层松解术作为中西医理论体系结合,且中医特色鲜明的治疗手段,应用于该疾病的治疗,对于控制症状、改善关... 风湿性多肌痛以肩胛带及骨盆带的肌肉疼痛、关节受限为主要症状表现,目前指南主要以口服激素为主要治疗方案,不良作用明显。针刀分层松解术作为中西医理论体系结合,且中医特色鲜明的治疗手段,应用于该疾病的治疗,对于控制症状、改善关节功能有较好效果。 展开更多
关键词 针刀 风湿性多肌痛 分层 医案
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纸质文献修复实践——书画装裱镜片技艺虚拟仿真实验项目
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作者 张子迎 齐文台 +1 位作者 纪秀文 周华 《数字与缩微影像》 2024年第1期16-19,共4页
本文以装裱知识点为核心内容,借助虚拟仿真技术,从装裱过程的全真模拟、重要工具及材料的处理使用以及装裱作品的分层结构展示等三个方面,对传统手工技艺类的虚拟仿真实验进行了探索与实践。
关键词 纸质文献 修复 书画装裱镜片技艺 虚拟仿真 分层解
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粘-弹层合板的阻尼振动和横向应力 被引量:5
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作者 杨少红 王安稳 《海军工程大学学报》 CAS 2003年第3期69-74,共6页
应用混合分层理论在板的厚度方向取二次插值函数描述每个数值层内位移沿厚度方向的变化规律,采用三次和四次插值函数描述横向应力沿厚度方向的变化,推导出粘-弹层合板的动力学方程,并得出简支粘-弹层合板自由阻尼振动的解.数值结果不仅... 应用混合分层理论在板的厚度方向取二次插值函数描述每个数值层内位移沿厚度方向的变化规律,采用三次和四次插值函数描述横向应力沿厚度方向的变化,推导出粘-弹层合板的动力学方程,并得出简支粘-弹层合板自由阻尼振动的解.数值结果不仅与三维结果吻合较好,且能够计算合理协调的横向应力. 展开更多
关键词 粘-弹层合板 阻尼振动 横向应力 混合分层理论 控制方程 插值函数 混合分层解 模量 三维理论
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A method for absorption compensation based on adaptive molecular decomposition 被引量:1
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作者 汪玲玲 高静怀 张明 《Applied Geophysics》 SCIE CSCD 2010年第1期74-87,100,共15页
In this paper,we present a new method for seismic stratigraphic absorption compensation based on the adaptive molecular decomposition.Using this method,we can remove most of the effects resulting from wavelets truncat... In this paper,we present a new method for seismic stratigraphic absorption compensation based on the adaptive molecular decomposition.Using this method,we can remove most of the effects resulting from wavelets truncation and interference which usually exist in the common time-frequency absorption compensation method.Based on the assumption that the amplitude spectrum of the source wavelet is smooth,we first construct a set of adaptive Gabor frames based on the time-variant properties of the seismic signal to transform the signal into the time-frequency domain and then extract the slowly varying component(the wavelet's time-varying amplitude spectrum) in each window in the timefrequency domain.Then we invert the absorption compensation filter parameters with an objective function defined using the correlation coefficients in each window to get the corresponding compensation filters.Finally,we use these filters to compensate the timefrequency spectrum in each window and then transform the time-frequency spectrum to the time domain to obtain the absorption-compensated signal.By using adaptive molecular decomposition,this method can adapt to isolated and overlapped seismic signals from the complex layers in the inhomogeneous viscoelastic medium.The viability of the method is verified by synthetic and real data sets. 展开更多
关键词 wadaptive molecular decomposition ABSORPTION COMPENSATION RESOLUTION
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非均匀随机散射介质层的多次散射和热辐射的分层迭代解 被引量:2
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作者 梁子长 金亚秋 《物理学报》 SCIE EI CAS CSCD 北大核心 2003年第6期1319-1325,共7页
为纳入矢量辐射传输方程的多次散射 ,将非均匀平行分层分布的随机散射介质划分成多个薄层 ,利用各薄层的低阶Mueller矩阵解推导出整层的高阶散射迭代解 .用这一方法计算了具有占空比、粒子大小和温度廓线非均匀分布的平行分层随机密集... 为纳入矢量辐射传输方程的多次散射 ,将非均匀平行分层分布的随机散射介质划分成多个薄层 ,利用各薄层的低阶Mueller矩阵解推导出整层的高阶散射迭代解 .用这一方法计算了具有占空比、粒子大小和温度廓线非均匀分布的平行分层随机密集球形粒子积雪层的极化热辐射 .数值结果与一层均匀随机散射层的离散坐标 特征值方法作了比较 ,讨论了多次散射和热辐射与散射层各特征参数的关系 。 展开更多
关键词 非均匀随机散射介质层 多次散射 热辐射 分层迭代 平行分层 矢量辐射传输方程 积雪层
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Thermal Induced Periodic Phase Separation in Polymer Blends
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作者 孙喆 宋海华 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期99-101,共3页
Simulations were carried out for studying the periodic phase separation of a symmetric binary polymer blend on the basis of Cahn-Hilliard-Cook theory. The time dependent interaction parameter x(τ) was assumed to un... Simulations were carried out for studying the periodic phase separation of a symmetric binary polymer blend on the basis of Cahn-Hilliard-Cook theory. The time dependent interaction parameter x(τ) was assumed to undergo a step-wise oscillation. The hierarchic structures composed of both large and small domains were obtained. The mechanism of the periodic formation of hierarchic structures was also demonstrated. 展开更多
关键词 Periodic spinodal decomposition Simulations Hierarchic structures
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Dynamic hierarchy description and constraint rules of flexibility workflow
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作者 杨飞 尹宝林 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期474-478,共5页
A dynamic hierarchical description method for workflow is presented. The method provides a dynamic hierarchical way to define a workflow with non-determinate or dynamic factors. With this method, the main process defi... A dynamic hierarchical description method for workflow is presented. The method provides a dynamic hierarchical way to define a workflow with non-determinate or dynamic factors. With this method, the main process defined at build-time can be reified and extended by the principle of the sub-organizations at either the build-time or the run-time. To ensure the consistency and integrity of the description, a series of constraint rules are also discussed to realize seamless integration between a decomposed process and its original one. This approach supports the description of unpredictable uncertainties, the dynamic hierarchy of business process, and the dynamic modification of enterprise organizations, and all of these improve the flexibility and extendability of workflow management systems dramatically. 展开更多
关键词 flexible workflow dynamic hierarchy description task decomposition split process
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Unveiling the decomposition mechanism of formic acid on Pd/WC(0001) surface by using density function theory 被引量:1
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作者 Jinhua Zhang Yuanbin She 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第3期415-425,共11页
In pursuit of low-cost direct formic acid fuel cells,tungsten carbide(WC)supported Pd catalyst is considered as an ideal candidate for efficient decomposition of formic acid due to low Pd utilization and excellent per... In pursuit of low-cost direct formic acid fuel cells,tungsten carbide(WC)supported Pd catalyst is considered as an ideal candidate for efficient decomposition of formic acid due to low Pd utilization and excellent performance.Herein,different adsorption configurations and active sites of the intermediates,involved in the HCOOH decomposition,on WC(0001)-supported Pd monolayer(Pd/WC(0001))surface investigated by using density functional theory.The results reveal that trans-HCOOH,HCOO,cis-COOH,trans-COOH,HCO,CO,H2 O,OH and H exhibit chemisorption on Pd/WC(0001)surface,whereas cis-HCOOH and CO2 exhibit weak interactions with Pd/WC(0001)surface.In addition,the minimum energy pathways of HCOOH decomposition are analyzed to generate CO and CO2 due to the fracture of C–H,H–O and C–O bonds.The adsorbed HCOOH,HCOO,mH COO,cis-COOH and trans-COOH configurations exhibit dissociation rather than desorption.CO formation occurs through the decomposition of cis-COOH,trans-COOH and HCO,whereas the CO2 formation happens due to the decomposition of HCOO.It is found that the most favorable pathway for HCOOH decomposition on Pd/WC(0001)surface is HCOOH→HCOO→CO2,where the formation of CO2 from HCOO dehydrogenation determines the reaction rate.Overall,CO2 is the most dominant product of HCOOH decomposition on Pd/WC(0001)surface.The presence of WC,as monolayer Pd carrier,does not alter the catalytic behavior of Pd and significantly reduces the Pd utilization. 展开更多
关键词 Density functional theory Formic acid Direct formic acid fuel cells WC(0001)-supported Pd monolayer Decomposition mechanism
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青藏铁路含保温夹层路基厚度与地温关系的研究
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作者 刘彩云 郭尊光 《太原师范学院学报(自然科学版)》 2015年第1期66-69,共4页
通过对青藏铁路风火山段含有保温夹层的路基建立均匀介质分层纯导热模型并运用分层近似解法求出冻土表层的温度函数,结合Lachenbruch给出的冻土层的理论温度表达式,得到了路基填料层、保温层、地表年平均温度与正弦变化温度的振幅比三... 通过对青藏铁路风火山段含有保温夹层的路基建立均匀介质分层纯导热模型并运用分层近似解法求出冻土表层的温度函数,结合Lachenbruch给出的冻土层的理论温度表达式,得到了路基填料层、保温层、地表年平均温度与正弦变化温度的振幅比三者之间的隐式方程,并应用该方程对三者之间的关系进行了分析. 展开更多
关键词 多年冻土 保温层 分层纯导热模型 分层近似
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Maximum Effective Hole Mathematical Modei and Exact Solution for Commingled Reservoir 被引量:2
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作者 孙贺东 刘磊 +1 位作者 周芳德 高承泰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第5期550-554,共5页
The maximum effective hole-diameter mathematical modei describing the flow of slightly compressible fluid through a commingled reservoir was solved rigorously with consideration of wellbore storage and different skin ... The maximum effective hole-diameter mathematical modei describing the flow of slightly compressible fluid through a commingled reservoir was solved rigorously with consideration of wellbore storage and different skin factors. The exact solutions for wellbore pressure and the production rate obtained from layer j for a well production at a constant rate from a radial drainage area with infinite and constant pressure and no flow outer boundary condition were expressed in terms of ordinary Bessel functions. These solutions were computed numerically by the Crump's numerical inversion method and the behavior of systems was studied as a function of various reservoir parameters. The modei was compared with the real wellbore radii modei. The new modei is numerically stable when the skin factor is positive and negative, but the real wellbore radii modei is numerically stable only when the skin factor is positive. 展开更多
关键词 well-testing mathematical model effective hole diameter layered reservoir
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Spectral decomposition method for predicting magmatic intrusion into a coal bed 被引量:3
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作者 Wang Xin Chen Tongjun +1 位作者 Cui Ruofei Xu Yongzhong 《International Journal of Mining Science and Technology》 2012年第4期447-452,共6页
Accurate prediction of magmatic intrusion into a coal bed is illustrated using the method of seismic spectral decomposition.The characteristics of coal seismic reflections are first analyzed and the effect of variable... Accurate prediction of magmatic intrusion into a coal bed is illustrated using the method of seismic spectral decomposition.The characteristics of coal seismic reflections are first analyzed and the effect of variable time windows and domain frequencies on the spectral decomposition are examined.The higher domain frequency of coal bed reflections using the narrower STFT time window,or the smaller ST scale factor,are acceptable.When magmatic rock intrudes from the bottom of the coal bed the domain frequency of the reflections is decreased slightly,the frequency bandwidth is narrowed correspondingly,and the response from spectral decomposition is significantly reduced.Intrusion by a very thin magmatic rock gives a spectral decomposition response that is just slightly less than what is seen from a normal coal bed.Results from an actual mining area were used to validate the method.Predicting the boundary of magmatic intrusions with the method discussed herein was highly accurate and has been validated by observations from underground mining. 展开更多
关键词 Coal bed reflection Spectral decomposition Influence factors Magmatic intrusion predicting
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A Genetic Fuzzy Analytical Hierarchy Process Based Projection Pursuit Method for Selecting Schemes of Water Transportation Projects 被引量:1
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作者 JIN Juliang LI Lei +1 位作者 WANG Wensheng ZHANG Ming 《Journal of Ocean University of China》 SCIE CAS 2006年第4期289-294,共6页
The optimal selection of schemes of water transportation projects is a process of choosing a relatively optimal scheme from a number of schemes of water transportation programming and management projects, which is of ... The optimal selection of schemes of water transportation projects is a process of choosing a relatively optimal scheme from a number of schemes of water transportation programming and management projects, which is of importance in both theory and practice in water resource systems engineering. In order to achieve consistency and eliminate the dimensions of fuzzy qualitative and fuzzy quantitative evaluation indexes, to determine the weights of the indexes objectively, and to increase the differences among the comprehensive evaluation index values of water transportation project schemes, a projection pursuit method, named FPRM-PP for short, was developed in this work for selecting the optimal water transportation project scheme based on the fuzzy preference relation matrix. The research results show that FPRM-PP is intuitive and practical, the correction range of the fuzzy rained is both stable and accurate; preference relation matrix A it produces is relatively small, and the result obtherefore FPRM-PP can be widely used in the optimal selection of different multi-factor decision-making schemes. 展开更多
关键词 water transportation project optimal selection of schemes fuzzy analytical hierarchy process projection pursuit genetic algorithm
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Effect of bismuth tungstate with different hierarchical architectures on photocatalytic degradation of norfloxacin under visible light 被引量:5
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作者 Jia-jia WANG Lin TANG +5 位作者 Guang-ming ZENG Yao-yu ZHOU Yao-cheng DENG Chang-zheng FAN Ji-lai GONG Ya-ni LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第8期1794-1803,共10页
The photocatalytic degradation of norfloxacin by bismuth tungstate(Bi2WO6)with different hierarchical architectures wasinvestigated under visible light irradiation.Bi2WO6was prepared by hydrothermal method with the re... The photocatalytic degradation of norfloxacin by bismuth tungstate(Bi2WO6)with different hierarchical architectures wasinvestigated under visible light irradiation.Bi2WO6was prepared by hydrothermal method with the reaction solution pH rangingfrom4to11.The relatively ultrathin Bi2WO6nanoflakes prepared at pH4showed excellent adsorption and photodegradationefficiency towards norfloxacin.The characterization results showed that Bi2WO6prepared at pH4had a larger specific area andfaster photo-generated carrier separation rate.The decay rate reached the maximum in weak alkaline reaction solution,which couldbe attributed to the presence of moderate OH-anions.The present study demonstrated that the smaller size of Bi2WO6could be anefficient photocatalyst on the degradation of norfloxacin in the aquatic environment. 展开更多
关键词 NORFLOXACIN bismuth tungstate hierarchical architecture photocatalytic degradation size effect
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Integration of 2D layered CdS/WO_(3) S-scheme heterojunctions and metallic Ti_(3)C_(2) MXene-based Ohmic junctions for effective photocatalytic H_(2) generation 被引量:18
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作者 Junxian Bai Rongchen Shen +3 位作者 Zhimin Jiang Peng Zhang Youji Li Xin Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第2期359-369,共11页
The rapid recombination of photo-generated electron-hole pairs,insufficient active sites,and strong photocorrosion have considerably restricted the practical application of Cd S in photocatalytic fields.Herein,we desi... The rapid recombination of photo-generated electron-hole pairs,insufficient active sites,and strong photocorrosion have considerably restricted the practical application of Cd S in photocatalytic fields.Herein,we designed and constructed a 2D/2D/2D layered heterojunction photocatalyst with cascaded 2D coupling interfaces.Experiments using electron spin resonance spectroscopy,ultraviolet photoelectron spectroscopy,and in-situ irradiation X-ray photoelectron spectroscopy were conducted to confirm the 2D layered CdS/WO_(3) step-scheme(S-scheme)heterojunctions and CdS/MX ohmic junctions.Impressively,it was found that the strong interfacial electric fields in the S-scheme heterojunction photocatalysts could effectively promote spatially directional charge separation and transport between CdS and WO_(3) nanosheets.In addition,2D Ti_(3)C_(2) MXene nanosheets with a smaller work function and excellent metal conductivity when used as a co-catalyst could build ohmic junctions with Cd S nanosheets,thus providing a greater number of electron transfer pathways and hydrogen evolution sites.Results showed that the highest visible-light hydrogen evolution rate of the optimized MX-Cd S/WO_(3) layered multi-heterostructures could reach as high as 27.5 mmol/g/h,which was 11.0 times higher than that of pure CdS nanosheets.Notably,the apparent quantum efficiency reached 12.0% at 450 nm.It is hoped that this study offers a reliable approach for developing multifunctional photocatalysts by integrating S-scheme and ohmic-junction built-in electric fields and rationally designing a 2D/2D interface for efficient light-to-hydrogen fuel production. 展开更多
关键词 Photocatalytic hydrogen evolution 2D layered S-scheme heterojunction CdS nanosheets WO_(3)nanosheets Ti_(3)C_(2)MXene-based ohmic junctions Cascade 2D coupling interfaces
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Controlled Release of the Indomethacin Microencapsulation Based on Layer-by-layer Assembly by Polyelectrolyte Multilayers
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作者 CHEN You-fang LIN Xian-fu 《Chinese Journal of Biomedical Engineering(English Edition)》 2007年第1期8-13,共6页
Indomethacin has been encapsulated with polyelectrolyte multilayers for controlled release. Gelatin and alginate were alternatively deposited on indomethacin microcrystals. The released amount of indomethacin from coa... Indomethacin has been encapsulated with polyelectrolyte multilayers for controlled release. Gelatin and alginate were alternatively deposited on indomethacin microcrystals. The released amount of indomethacin from coated microcrystals in pH6. 8 phosphate buffer solution (PBS) was measured with a UV spectrophometer. The polyelectrolyte multilayer capsule thickness was proved to control the release rate. The effects of osmotic pressure existed during the release process of indomethacin from microcapsules coated by (gelatin/alginate) 4. 展开更多
关键词 INDOMETHACIN ENCAPSULATED Controlled release SELF-ASSEMBLY POLYELECTROLYTE
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H2 Dissociation by Au1-Doped Closed-Shell Titanium Oxide Cluster Anions
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作者 Li-xue Jiang Xiao-na Li +2 位作者 Zi-yu Li Hai-fang Li Sheng-gui He 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第4期457-462,614,共7页
Dissociation of molecular hydrogen (H2) is extensively studied to understand the mechanism of hydrogenation reactions. In this study, H2 dissociation by Aul-doped closed-shell titanium oxide cluster anions AuTi3O7 a... Dissociation of molecular hydrogen (H2) is extensively studied to understand the mechanism of hydrogenation reactions. In this study, H2 dissociation by Aul-doped closed-shell titanium oxide cluster anions AuTi3O7 and AuTi3O8 has been identified by mass spectrometry and quantum chemistry calculations. The clusters were generated by laser ablation and mass- selected to react with H2 in art ion trap reactor. In the reaction of AuTi3O8 with H2, the ion pair Au+-O22 rather than Au+-O2 is the active site to promote H2 dissociation. This finding is in contrast with the previous result that the lattice oxygen is usually the reactive oxygen species in H2 dissociation. The higher reactivity of the peroxide species is further supported by frontier molecular orbital analysis. This study provides new insights into gold catalysis involving H2 activation and dissociation. 展开更多
关键词 Gold H2 dissociation Closed-shell anions Mass spectrometry Density func tional theory calculations
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