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Ageing process of pre-precipitation phase in Ni_(0.75)Al_(0.05)Fe_(0.2) alloy based on phase field method 被引量:4
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作者 董卫平 王永欣 +1 位作者 陈铮 杨坤 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第5期1105-1111,共7页
By utilizing phase field method combined with analysis on free energy and interatomic potentials, pre-precipitation phase formation and transformation process of Ni0.75Al0.05Fe0.2 alloy in early precipitation stage du... By utilizing phase field method combined with analysis on free energy and interatomic potentials, pre-precipitation phase formation and transformation process of Ni0.75Al0.05Fe0.2 alloy in early precipitation stage during the ageing process under 1 000 K were studied. And free energy, microstructures, compositions and volume fractions of pre-precipitation phase and equilibrium phase were analyzed. The simulation results indicate that nonstoichiometric Llo pre-precipitation phase formed first, and then would gradually transform into L12 equilibrium phase. It is discovered that the phase transformation process was closely related to free energy and interatomic potentials. Additionally, it is revealed that free energy of Llo pre-precipitation phase was higher and interatomic potential was smaller than that of L12 equilibrium phase. Therefore, it is concluded that Llo phase was unstable, and phase transformation would occur to L12 which was more stable. 展开更多
关键词 pre-precipitation phase equilibrium phase interatomic potentials free energy phase field method
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New subspace algorithm for blind channel estimation in OFDM systems
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作者 黄学军 余松煜 毕厚杰 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期132-135,共4页
In order to increase the transmission efficiency,a subspace-based algorithm for blind channel estimation using second-order statistics is proposed in orthogonal frequency division multiplexing (OFDM) systems.Because t... In order to increase the transmission efficiency,a subspace-based algorithm for blind channel estimation using second-order statistics is proposed in orthogonal frequency division multiplexing (OFDM) systems.Because the transmission equation of OFDM systems does not exactly have the desired structure to directly derive a subspace algorithm,the algorithm first divides the OFDM signals into three parts,then,by exploiting the redundancy introduced by the cyclic prefix (CP) in OFDM signals,a new equation with Toeplitz channel matrix is derived.Based on the equation,a new blind subspace algorithm is developed.Toeplitz structure eases the derivation of the subspace algorithm and practical computation.Moreover the algorithm does not change the existing OFDM system,is robust to channel order overdetermination,and the channel zero locations.The performances are demonstrated by simulation results. 展开更多
关键词 orthogonal frequency division multiplexing (OFDM) blind channel estimation subspace algorithm
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孙子的信息观初探
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作者 韩石萍 《洛阳师专学报(自然科学版)》 1996年第4期81-85,共5页
关键词 《孙子兵 信息观 将帅职能 用间法 动敌 信息收集方 中国 相敌
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Web multimedia information retrieval using improved Bayesian algorithm 被引量:3
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作者 余铁军 陈纯 +1 位作者 余铁民 林怀忠 《Journal of Zhejiang University Science》 EI CSCD 2003年第4期415-420,共6页
The main thrust of this paper is application of a novel data mining approach on the log of user' s feedback to improve web multimedia information retrieval performance. A user space model was constructed based... The main thrust of this paper is application of a novel data mining approach on the log of user' s feedback to improve web multimedia information retrieval performance. A user space model was constructed based on data mining, and then integrated into the original information space model to improve the accuracy of the new information space model. It can remove clutter and irrelevant text information and help to eliminate mismatch between the page author' s expression and the user' s understanding and expectation. User spacemodel was also utilized to discover the relationship between high-level and low-level features for assigning weight. The authors proposed improved Bayesian algorithm for data mining. Experiment proved that the au-thors' proposed algorithm was efficient. 展开更多
关键词 Relevant feedback Web log mining Improved Bayesian algorithm User space model
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Alterable-element Method for Vehicle-bridge Interaction Considering the Transient Jump of Wheel 被引量:6
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作者 吴川 刘学文 黄醒春 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第3期330-335,共6页
The so called "alterable-element method" (AEM) was introduced to deal with the coupling interac-tion of vehicle and sub-structure considering the actual transient jump of wheel, while the classical "con... The so called "alterable-element method" (AEM) was introduced to deal with the coupling interac-tion of vehicle and sub-structure considering the actual transient jump of wheel, while the classical "contact all along" assumption based on which wheels and lower structure are always contact was abandoned. The alterable element used in this method is a conceptional element, which is used to calculate the coupling interaction of upper and lower structures and has some typical characteristics: firstly it flows along with the moving of contact point; secondly whether it is used for calculation depends on the contact state; thirdly its sizes could change according to specific problems and so on. VISUAL FORTRAN program was coded, and different moving vehicle models were presented taking into consideration the effects of random corrugation in the numerical study. The numerical solutions are favored comparing with the results obtained by alternative methods when there is no jump phenomenon existed. With abrupt irregularity, the transient jump of wheel was studied using the present method. 展开更多
关键词 alterable-element method (AEM) vehicle-bridge interaction transient jump
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Mechanism analysis of ions interaction in MgCl_2/LiCl solution and effect of lithium on ammonia precipitation products
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作者 谈进 吴争平 +3 位作者 孙元兵 张锦玲 尹周澜 陈启元 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第1期319-328,共10页
Producing magnesium hydroxide is the basic way to utilize magnesium resources of natural brines. However, the effect of lithium on properties of product is always neglected. The interaction between ions in magnesium c... Producing magnesium hydroxide is the basic way to utilize magnesium resources of natural brines. However, the effect of lithium on properties of product is always neglected. The interaction between ions in magnesium chloride solution containing lithium was illustrated based on the experimental results, and the effect of lithium on the crystallization of magnesium was clarified. The results of X-ray diffraction(XRD), scanning election microscope(SEM), Fourier transform infrared spectroscopy(FTIR), thermogravimetry analysis(TGA) and laser particle size analysis indicate that the effect of lithium is not obvious on the crystal phase and morphology of the products. But the XRD relative intensity of(001) surface of magnesium hydroxide declines, the specific surface area reduces apparently and the additive mass of lithium affects the heat loss rates of precipitations obviously. Quantum chemical calculations on the interactional systems of Mg(H2O)2+6 and Li(H2O)+4 were performed using B3LYP/6-311 G basis set. The results show that when the distance of Mg2+ and Li+ is 7-10 , the interaction energy is high and the trend of solvation is strong, which would make hydroxide ions easier to combine with hydrogen ions in ammonia precipitation process. And the absolute value of solvation free energy reduces significantly in MgCl2 solution(1 mol/L) containing lithium ion. 展开更多
关键词 magnesium hydroxide LITHIUM ammonia precipitation interaction between ions solvation free energy
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Novel Control Vector Parameterization Method with Differential Evolution Algorithm and Its Application in Dynamic Optimization of Chemical Processes 被引量:2
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作者 孙帆 钟伟民 +1 位作者 程辉 钱锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第1期64-71,共8页
Two general approaches are adopted in solving dynamic optimization problems in chemical processes, namely, the analytical and numerical methods. The numerical method, which is based on heuristic algorithms, has been w... Two general approaches are adopted in solving dynamic optimization problems in chemical processes, namely, the analytical and numerical methods. The numerical method, which is based on heuristic algorithms, has been widely used. An approach that combines differential evolution (DE) algorithm and control vector parameteri- zation (CVP) is proposed in this paper. In the proposed CVP, control variables are approximated with polynomials based on state variables and time in the entire time interval. Region reduction strategy is used in DE to reduce the width of the search region, which improves the computing efficiency. The results of the case studies demonstrate the feasibility and efficiency of the oroposed methods. 展开更多
关键词 control vector pararneterization differential evolution algorithm dynamic optimization chemical processes
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A land use-based spatial analysis method for human health risk assessment of heavy metals in soil and its application in Zhuzhou City, Hunan Province, China 被引量:5
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作者 王振兴 虢清伟 +3 位作者 杨志辉 孙国庆 叶万生 胡习邦 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第8期1915-1923,共9页
A land use- and geographical information system-based framework was presented for potential human health risk analysis using soil sampling data obtained in Zhuzhou City, Hunan Province, China. The results show that he... A land use- and geographical information system-based framework was presented for potential human health risk analysis using soil sampling data obtained in Zhuzhou City, Hunan Province, China. The results show that heavy metal content in soil significantly differs among different land use types. In total, 8.3% of the study area has a hazard index(HI) above the threshold of 1.0. High HIs are recorded mainly for industrial areas. Arsenic((29)87%) and the soil ingestion pathway(about 76%) contribute most to the HI. The mean standardized error and root-mean-square standardized error data indicate that the land use-based simulation method provides more accurate estimates than the classic method, which applies only geostatistical analysis to entire study area and disregards land use information. The findings not only highlight the significance of industrial land use, arsenic and the soil ingestion exposure pathway, but also indicate that evaluating different land use-types can spatially identify areas of greater concern for human health and better identify health risks. 展开更多
关键词 SOIL heavy metal health risk land use geographic information system(GIS)
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Design and Implementation of mobile GIS application based on Android 被引量:3
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作者 SUN Yong WU Guanxiang 《International Journal of Technology Management》 2014年第4期61-63,共3页
This paper analyzes the key technology of mobile GIS development, discusses the design method of mobile GIS spatial data management, visualization of spatial data And Spatial data query, tinder Object oriented mode. A... This paper analyzes the key technology of mobile GIS development, discusses the design method of mobile GIS spatial data management, visualization of spatial data And Spatial data query, tinder Object oriented mode. And we develop a set of mobile GIS basic software platform in the Android platform, and tested in the mainstream smart mobile phone with Android operating system, test results show that the software platform can run smoothly. Other users can development a variety of mobile GIS to call the platform through an application service interface. 展开更多
关键词 ANDROID mobile GIS map tiles STREET mobile intelligent terminal
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Damage detection of frames using the increment of lateral displacement change
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作者 王建民 陈龙珠 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第3期202-212,共11页
The method proposed in this paper is based on the fact that the damage in different types of structural members has distinctive influence on the structural stiffness. The intrinsic mechanical property of the structure... The method proposed in this paper is based on the fact that the damage in different types of structural members has distinctive influence on the structural stiffness. The intrinsic mechanical property of the structure is tapped and fully utilized for damage detection. The simplified model of the flexibility of frames treats the individual storeys as springs in series and the frame as an equivalent column. It fully considers the main deformation of all beams and columns in the frame. The deformation property of the simplified model accorded well with that of the actual frame model. The obtained increment of lateral displacement change (IOLDC) at the storey level was found to be very sensitive to the local damage in the frame. A damage detection method is pro- posed using the IOLDCs as the damage identification parameters. Numerical examples demonstrate the potential applicability of this method. 展开更多
关键词 Damage detection Increment of lateral displacement change Static test FRAME Equivalent column
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The Application of the Bursa Model to the Integration of GPS Time Series
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作者 Wang Ziyan Lin Shu +2 位作者 Wu Yanqiang Zhan Wei Ding Xiaoguang 《Earthquake Research in China》 2014年第1期46-53,共8页
In this paper the method of combining the Bursa model to integrate several regional time series to derive a unified global time series is introduced in detail. Then,an example taken from CMONOC( Crustal Movement Obser... In this paper the method of combining the Bursa model to integrate several regional time series to derive a unified global time series is introduced in detail. Then,an example taken from CMONOC( Crustal Movement Observation Network of China) is used to test if the combination method is feasible. The precision of the integrated time series with the combination method is below 2mm( North),3mm( East),that is same as the results from the direct integration of the time series and the precision of the baseline is below 6mm,which proves that the combination method can be used to integrate several regional time series to derive a unified global time series. 展开更多
关键词 GPS time series INTEGRATION Bursa model
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Application of ACO algorithm in protein structure prediction
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作者 唐好选 曲毅 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第1期111-114,共4页
The hydrophobic-polar (HP) lattice model is an important simplified model for studying protein folding. In this paper, we present an improved ACO algorithm for the protein structure prediction. In the algorithm, the &... The hydrophobic-polar (HP) lattice model is an important simplified model for studying protein folding. In this paper, we present an improved ACO algorithm for the protein structure prediction. In the algorithm, the "lone"ethod is applied to deal with the infeasible structures, and the "oint mutation and reconstruction"ethod is applied in local search phase. The empirical results show that the presented method is feasible and effective to solve the problem of protein structure prediction, and notable improvements in CPU time are obtained. 展开更多
关键词 protein structure prediction HP lattice model ACO algorithm
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Accessibility and Integration Study of Part of the Abu Dhabi 2030 Master Plan by Using Space Syntax
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作者 Rim Meziani 《Journal of Civil Engineering and Architecture》 2017年第1期81-90,共10页
This paper studies the accessibility of open spaces and facilities and the integration of streets to the whole urban system of the Emirati neighbourhood of the Business District of the Abu Dhabi 2030 Master Plan. For ... This paper studies the accessibility of open spaces and facilities and the integration of streets to the whole urban system of the Emirati neighbourhood of the Business District of the Abu Dhabi 2030 Master Plan. For this purpose, axial lines were produced by applying space syntax theory, Depthmap software. The research aims to verify the location of open spaces and facilities, such as schools, in relation to the location of public transportation stops (bus, metro and tram), in order to check their accessibility within walking distances. The objective is to pay attention to the relationship between land use and transportation in the planning phase for future interventions or proposals, in other words, to improve the accessibility of public spaces or buildings by pedestrians in order to comply with the vision of the Abu Dhabi 2030 Master Plan and its promotion of walkability and cycling. Although many measures will be taken at the scale of urban design to provide shaded open spaces and sidewalks, saving pedestrians from walking long distances shall be done in the planning phase, the challenge remains to create a micro climate to increase the ease of walking in the heat and decrease dependence on cars for mobility. 展开更多
关键词 Abu Dhabi 2030 Master Plan ACCESSIBILITY space syntax.
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Joint Link Allocation and Rate Assignment Algorithm for Multi-Channel Wireless Networks 被引量:1
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作者 Yu Xutao Fang Xin Zhang Zaichen 《China Communications》 SCIE CSCD 2012年第9期96-106,共11页
This paper presents a link allocation and rate assignment algorithm for multi-channel wireless networks. The objective is to reduce network con-flicts and guarantee the fairness among links. We first design a new netw... This paper presents a link allocation and rate assignment algorithm for multi-channel wireless networks. The objective is to reduce network con-flicts and guarantee the fairness among links. We first design a new network model. With this net-work model, the multi-channel wireless network is divided into several subnets according to the num-ber of channels. Based on this, we present a link allocation algorithm with time complexity O(l^2)to al-locate all links to subnets. This link allocation algo-rithm adopts conflict matrix to minimize the network contention factor. After all links are allocated to subnets, the rate assignment algorithm to maximize a fairness utility in each subnet is presented. The rate assignment algorithm adopts a near-optirml al-gorithm based on dual decomposition and realizes in a distributed way. Simulation results demonstrate that, compared with IEEE 802.11b and slotted see-ded channel hopping algorithm, our algorithm de-creases network conflicts and improves the net-work throughput significantly. 展开更多
关键词 multi-channel networks link allocation rate assignment conflict matrix fairness utilityfunction
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Multicast Scheduling Algorithm Supporting Spatial Mini-slot Reuse for IEEE 802.16 Mesh Networks
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作者 Saleh Yousefi Morteza Maleki 《China Communications》 SCIE CSCD 2013年第1期116-133,共18页
Abstract: In this paper, we propose a mecha- nism for multicast data transmission in IEEE 802.16 mesh networks aimed at increasing the throughput by incorporating mini-slot spatial reuse. The proposed mechanism inclu... Abstract: In this paper, we propose a mecha- nism for multicast data transmission in IEEE 802.16 mesh networks aimed at increasing the throughput by incorporating mini-slot spatial reuse. The proposed mechanism includes two novel algorithms: a source-based multicast tree topology construction algorithm followed by an interference-aware multieast scheduling algorithm. The proposed multicast interfer- ence-aware scheduling algorithm can be ap- plied to both source-based and rendez- vous-based multicast tree topologies. Results of our simulation study show that in compari- son to the mechanism used for the IEEE 802.16's standard, the proposed multicast tree generation algorithm reduces the number of consumed mini-slots by 64% on average. Moreover, using the proposed interfer- ence-aware scheduling algorithm decreases the number of required mini-slots by a further 22% on average. Therefore, the proposed mul- ticast scheduling mechanism shows a higher throughput than the previous approaches and it is more scalable with respect to increasing the number of multicast groups as well as in- creasing the number of members inside each multicast group. 展开更多
关键词 IEEE 802.16 WIMAX Meshmode MULTICAST scheduling interference spatial reuse
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SPATIAL COMPATIBLE USER GROUPING ALGORITHM FOR MULTIUSER MIMO SYSTEMS
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作者 Li Lei Niu Zhisheng 《Journal of Electronics(China)》 2007年第2期257-260,共4页
A spatial compatible user grouping algorithm is proposed to reduce CoChannel Interference (CCI) in Space Division Multiple Access (SDMA) multiuser Multiple Input Multiple Output (MIMO) systems. We evaluate the interfe... A spatial compatible user grouping algorithm is proposed to reduce CoChannel Interference (CCI) in Space Division Multiple Access (SDMA) multiuser Multiple Input Multiple Output (MIMO) systems. We evaluate the interferences among users by use of distances between row spaces spanned by users’ channel matrixes, then control frequency sharing according to the compatible user grouping algorithm. Results show that the row space distance algorithm outperforms others because it can fully utilize the information from users’ channel matrixes, especially the matrix structure information. The results also prove that the algorithm based on channel matrix structure analysis is a better candidate for spatial compatibility approximation. 展开更多
关键词 Multiple Input Multiple Output (MIMO) Space Division Multiple Access (SDMA) Multiuser system Radio resource management
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In Vitro and In Silico Studies of Lunacridine from Lunasia Amara Blanco as Anticancer
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作者 Zubair M. Sulaiman Subehan Lallo Natsir Djide 《Journal of Life Sciences》 2011年第8期639-645,共7页
Lunasia amara Blanco is a famous plant in South Sulawesi. It was used largely by local people as antibacteria and aphrodisiac. Quinoline alkaloid lunacridine was known as the active principle from Lunasia amara Blanco... Lunasia amara Blanco is a famous plant in South Sulawesi. It was used largely by local people as antibacteria and aphrodisiac. Quinoline alkaloid lunacridine was known as the active principle from Lunasia amara Blanco. Its activity was reported as a DNA Intercalating Topoisomerase II inhibitor. In this study, we have isolated and assayed the cytotoxic activity of lunacridine on P388 murine leukemia cells by MTT colorimetric assay (in vitro). Lunacridine showed the less cytotoxic activity with the IC50 of 39.52 μg/mL. With the aim to explore the structural determinants responsible for this activity, molecular docking study have been carried out with DNA model using AutoDock 4.0 software with various total of energy evaluations (in silico). The best docking reached at the total energy evaluations of 2.5 × 107 with the binding free energy of-6.63 kcal/mol. Analysis of the docking results was in accordance with the ability of lunacridine to intercalate between base pairs of DNA. Cytotoxic activity of lunacridine is less probably due to low affinity and molecular interaction. Therefore this study suggests to design and to develop lunacridine as a lead compound for anticancer drug. 展开更多
关键词 Lunasia amara Blanco lunacridine ANTICANCER P388 murine ubstitu cells docking.
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Cultural Binary Particle Swarm Optimization Algorithm and Its Application in Fault Diagnosis 被引量:1
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作者 黄海燕 顾幸生 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期474-481,共8页
Binary particle swarm optimization algorithm(BPSOA) has the excellent characters such as easy to implement and few set parameters.But it is tendentious to stick in the local optimal solutions and has slow convergence ... Binary particle swarm optimization algorithm(BPSOA) has the excellent characters such as easy to implement and few set parameters.But it is tendentious to stick in the local optimal solutions and has slow convergence rate when the problem is complex.Cultural algorithm(CA) can exploit knowledge extracted during the search to improve the performance of an evolutionary algorithm and show higher intelligence in treating complicated problems.So it is proposed that integrating binary particle swarm algorithm into cultural algorithm frame to develop a more efficient cultural binary particle swarm algorithm (CBPSOA) for fault feature selection.In CBPSOA,BPSOA is used as the population space of CA;the evolution of belief space adopts crossover,mutation and selection operations;the designs of acceptance function and influence function are improved according to the evolution character of BPSOA.The tests of optimizing functions show the proposed algorithm is valid and effective.Finally,CBPSOA is applied for fault feature selection.The simulations on Tennessee Eastman process (TEP) show the CBPSOA can perform better and more quickly converge than initial BPSOA.And with fault feature selection,more satisfied performance of fault diagnosis is obtained. 展开更多
关键词 cultural algorithm cultural binary particleswarm optimization algorithm fault feature selection fault diagnosis
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Research on the Scientific Meaning of Rule of Law in China
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作者 Zhen Liu 《Review of Global Academics》 2015年第2期525-527,共3页
Beyond the existing academic viewpoints, clarifying the scientific meaning of the rule of law in China in the binary interaction between subject and object is the prerequisite for reifying the rule of law in China fro... Beyond the existing academic viewpoints, clarifying the scientific meaning of the rule of law in China in the binary interaction between subject and object is the prerequisite for reifying the rule of law in China from an abstract symbol to a logic in action. The subject dimension of rule of law in China subsumes the legal consciousness, self confidence, independence and self-improvement of the subject. The object dimension of the rule of law in China focuses the relation mode and governance pattern between right and power. In the dimension of time, the rule of law in China is the unification of history and reality of China model. In the dimension of space, the rule of law in China is committed to seeking the right to speech, governance, management and development from the perspective of globalization. 展开更多
关键词 Rule of law in China GOVERNANCE PATTERN
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Square Wave Voltammetric Behavior of N,N-DiethyI-P-Nitroso Aniline an Indirect Method for Determination of Chlorpheniramin Maleate, Application of Pharmaceutical Formulations
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作者 Saddalah Tawfeeq Sulaiman Mohammed Ameen Abdullah Al-Imam Anfal Raad Mahmood 《Journal of Chemistry and Chemical Engineering》 2013年第4期292-298,共7页
The electrochemical behavior of N,N-diethyl-p-nitroso aniline was carried out using SWV (square wave voltammetric) at HMDE. A well defined reduction peak was observed at (-0.214) volt versus the reference electro... The electrochemical behavior of N,N-diethyl-p-nitroso aniline was carried out using SWV (square wave voltammetric) at HMDE. A well defined reduction peak was observed at (-0.214) volt versus the reference electrode (Ag/AgC1/sat. KCI), calibration curve was constructed in phosphate buffer (pH = 7.0), the relationship is linear within the concentration range 1.283 × 10.5 M - 3.66 × 10.5 M with the correlation (R = 0.9923). The serial addition ofCPM (chlorpheniramine maleate) leads to the decrease in the reduction current peak (Ip), quantitatively, the plot of Alp (Ip - Ip) where, Ip: Peak current of N, N-diethyl-p-nitroso aniline alone, lp: peak current of N,N-diethyl-p-nitroso aniline in the presence of CPM, versus concentration is linear within the concentration range 0.984 × 10-6 M - 9.756 × 10-6 M, the correlation coefficient was 0.9954. The method was successfully applied to determine CPM in different types of pharmaceutical formulations, and compared with standard method from British Pharmacopeia [1]. 展开更多
关键词 VOLTAMMETRIC chlorpheniramin maleate DETERMINATION pharmaceutical formulations.
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