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The modified Casson's equation and its application to pipe flows of shear-thickening fluid
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作者 Hao Xue 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第3期243-248,共6页
A few additional data from our previous experiments were plotted to emphasize the shear-thickening behavior ofdeoxy sickle erythrocyte (SS) suspension. A constitutive equation (named as FX equation) was developed ... A few additional data from our previous experiments were plotted to emphasize the shear-thickening behavior ofdeoxy sickle erythrocyte (SS) suspension. A constitutive equation (named as FX equation) was developed and applied to a cylindrical pipe flow of a shear-thickening fluid. A blunt velocity profile and its volume flow rate were calculated. The flow was non-viscous (potential) in the central part of the pipe (i.e. the central core or the central plug-flow), and became more and more viscous towards the wall of the pipe after a specific radial distance, which was determined by a critical shear rate of γF (named as Fung's shear rate). Furthermore, combining the FX equation with the original Casson's equation, the author obtained a modified Casson's equation by introducing γF. 展开更多
关键词 sickle erythrocyte Fung's shear rate FX equation Potential plug casson's plot
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Classification of Short Time Series in Early Parkinson’s Disease With Deep Learning of Fuzzy Recurrence Plots 被引量:8
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作者 Tuan D.Pham Karin Wardell +1 位作者 Anders Eklund Goran Salerud 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第6期1306-1317,共12页
There are many techniques using sensors and wearable devices for detecting and monitoring patients with Parkinson’s disease(PD).A recent development is the utilization of human interaction with computer keyboards for... There are many techniques using sensors and wearable devices for detecting and monitoring patients with Parkinson’s disease(PD).A recent development is the utilization of human interaction with computer keyboards for analyzing and identifying motor signs in the early stages of the disease.Current designs for classification of time series of computer-key hold durations recorded from healthy control and PD subjects require the time series of length to be considerably long.With an attempt to avoid discomfort to participants in performing long physical tasks for data recording,this paper introduces the use of fuzzy recurrence plots of very short time series as input data for the machine training and classification with long short-term memory(LSTM)neural networks.Being an original approach that is able to both significantly increase the feature dimensions and provides the property of deterministic dynamical systems of very short time series for information processing carried out by an LSTM layer architecture,fuzzy recurrence plots provide promising results and outperform the direct input of the time series for the classification of healthy control and early PD subjects. 展开更多
关键词 Deep learning early Parkinson’s disease(PD) fuzzy recurrence plots long short-term memory(LsTM) neural networks pattern classification short time series
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Marginal Distribution Plots for Proportional Hazards Models with Time-Dependent Covariates or Time-Varying Regression Coefficients
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作者 Qiqing Yu Junyi Dong George Wong 《Open Journal of Statistics》 2017年第1期92-111,共20页
Given a sample of regression data from (Y, Z), a new diagnostic plotting method is proposed for checking the hypothesis H0: the data are from a given Cox model with the time-dependent covariates Z. It compares two est... Given a sample of regression data from (Y, Z), a new diagnostic plotting method is proposed for checking the hypothesis H0: the data are from a given Cox model with the time-dependent covariates Z. It compares two estimates of the marginal distribution FY of Y. One is an estimate of the modified expression of FY under H0, based on a consistent estimate of the parameter under H0, and based on the baseline distribution of the data. The other is the Kaplan-Meier-estimator of FY, together with its confidence band. The new plot, called the marginal distribution plot, can be viewed as a test for testing H0. The main advantage of the test over the existing residual tests is in the case that the data do not satisfy any Cox model or the Cox model is mis-specified. Then the new test is still valid, but not the residual tests and the residual tests often make type II error with a very large probability. 展开更多
关键词 Cox’s Model TIME-DEPENDENT COVARIATE sEMI-PARAMETRIC sET-UP Diagnostic plot
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Integrated Assessment of Cardiac PET/MRI: Co-Registered PET and MRI Polar Plots by Mutual MR-Based Segmentation of the Left Ventricular Myocardium
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作者 Felix Nensa Thorsten D. Poeppel +6 位作者 Ercan Tezgah Philipp Heusch Kai Nassenstein Michael Forsting Andreas Bockisch Raimund Erbel Thomas Schlosser 《World Journal of Cardiovascular Diseases》 2017年第4期91-104,共14页
Background: In the present study, we sought to describe a procedure for the creation of co-registered positron emission tomography (PET) and magnetic resonance imaging (MRI) polar plots of cardiac PET/MRI examinations... Background: In the present study, we sought to describe a procedure for the creation of co-registered positron emission tomography (PET) and magnetic resonance imaging (MRI) polar plots of cardiac PET/MRI examinations, validate the resulting plots against available standard methods in patients with myocardial infarction and provide examples that demonstrate the advantage of the novel approach over existing standards. Methods: Co-registered LGE and PET short-axis images were transformed into polar maps based on a radial sampling pattern. LGE was automatically detected using an automated thresholding algorithm (ATA). In 20 PET/MRI examinations in patients with acute myocardial infarction, agreement between manual LGE assessment and the ATA classification was calculated. Also agreement between MRI-segmentation based PET polar plots and standard PET polar plots (created with the Corridor4DM software package) was assessed. Results: No statistically significant difference in infarct sizes between manual and ATA segmentation was found (p = 0.12). Both methods were highly correlated (Pearson’s r = 0.96, p Conclusion: A straightforward software approach for the creation of co-registered PET and MRI polar plots was described and successfully demonstrated in PET/MRI studies of myocardial infarction and inflammation. 展开更多
关键词 CARDIAC PET/MRI Bull’s Eye POLAR plot POLAR Map
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USA Plotted the 14th Dalai Lama's Fleeing
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《China's Tibet》 1999年第6期46-46,共1页
关键词 UsA plotted the 14th Dalai Lama’s Fleeing
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3S技术在拉萨市森林植被调查中的应用 被引量:24
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作者 任青山 杨小林 范文义 《东北林业大学学报》 CAS CSCD 北大核心 2001年第4期18-21,共4页
综合介绍了在西藏高寒生态条件下 ,利用 3S(RS、GIS、GPS)技术对拉萨市森林资源进行调查的可行性、技术路线及成果精度 ,并指出了
关键词 拉萨市 目视解译标志 判读勾绘 样地实测 森林植被 资源调查 Rs技术 GIs技术 GPs技术
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WLAN业务量特性分析及Hurst参数辨识 被引量:1
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作者 于秦 毛玉明 《电子科技大学学报》 EI CAS CSCD 北大核心 2007年第S2期1074-1076,1113,共4页
研究了无线局域网业务量统计特性;并运用R/S统计、方差-时间图和周期图法对测度无线局域网业务量自相似程度和突发性的重要参数Hurst参数进行辨识。仿真结果表明,无线局城网业务量具有自相似统计特性。通过比较其Hurst参数辨识的三种方... 研究了无线局域网业务量统计特性;并运用R/S统计、方差-时间图和周期图法对测度无线局域网业务量自相似程度和突发性的重要参数Hurst参数进行辨识。仿真结果表明,无线局城网业务量具有自相似统计特性。通过比较其Hurst参数辨识的三种方法可知:利用方差-时间图法和周期图法得到的Hurst参数辨识值接近相等,而R/S统计辨识的Hurst参数值偏离较大。对无线局域网流量的准确建模以及网络传输中流量控制和优化网络资源配置以及提高网络性能具有重要作用。 展开更多
关键词 HURsT参数 周期图法 R/s统计 方差-时间图法 无线局域网业务量
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基于Struts框架的智能小区物业管理系统的设计 被引量:1
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作者 孙亚 《重庆科技学院学报(自然科学版)》 CAS 2007年第4期49-52,共4页
设计一个基于Web的智能小区物业管理系统,采用J2EE平台及Struts架构的分布式多层结构体系。该系统的所有功能都通过服务器和用户浏览器之间交互完成,与系统相关的数据由数据库服务器来维护和组织。整个系统具有良好的可移植性、扩展性... 设计一个基于Web的智能小区物业管理系统,采用J2EE平台及Struts架构的分布式多层结构体系。该系统的所有功能都通过服务器和用户浏览器之间交互完成,与系统相关的数据由数据库服务器来维护和组织。整个系统具有良好的可移植性、扩展性和安全性,能方便地与其他子系统进行信息交互。 展开更多
关键词 物业管理系统 智能小区 sTRUTs框架
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基于GPRS及局域网的生产监控系统在油田中的应用 被引量:5
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作者 张华敏 王海伟 +4 位作者 陈子刚 焦磊 郑丹 潘永才 田茂 《湖北大学学报(自然科学版)》 CAS 北大核心 2008年第3期253-256,共4页
油田的生产特点决定其油井分布的不规则分散性,这就为油井的日常管理带来不便,而采用无线监测技术的方式对油井实现全天候在线监控可以克服此不足.通过基于GPRS及局域网的生产监控系统在油田的实施,不仅可以对油井实现24 h实时在线监测... 油田的生产特点决定其油井分布的不规则分散性,这就为油井的日常管理带来不便,而采用无线监测技术的方式对油井实现全天候在线监控可以克服此不足.通过基于GPRS及局域网的生产监控系统在油田的实施,不仅可以对油井实现24 h实时在线监测,及时发现油井的生产状况,并通过对实时数据的智能化分析,快速判断故障和及时采取相应措施,确保油井正常生产,提高油井有效生产时率. 展开更多
关键词 sCADA示功图 GPRs B/s浏览模式
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Electrochemical study on semiconductive properties of the passive film on rebar in concrete 被引量:4
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作者 ZHANG Yun-lian LI Qi-ling 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第8期1447-1452,共6页
The electrochemical behavior of metallic passive film on rebar in concrete is characterized by its semiconductive nature. The charge distribution at the interface between a semiconductor and an electrolyte is often de... The electrochemical behavior of metallic passive film on rebar in concrete is characterized by its semiconductive nature. The charge distribution at the interface between a semiconductor and an electrolyte is often determined by measuring the capacitance of the space-charge layer (CSC) as a function of the electrode potential (E). When the space charge-layer serves as the depletion layer, the relation of CS?C2 vs E resembles a Mott-Schottky plot (M-S plot). The semiconductive properties of the passive film on rebar in concrete were analyzed with M-S plots to study the effect of chloride ions and mineral admixtures on rebar passive films. Some rebar electrodes were immersed in simulated concrete pore solutions, while others were embedded in concrete with/without mineral admixtures. In saturated Ca(OH)2 solutions, the relation of CS ?C2 -E of rebar electrodes shows linear Mott- Schottky relationship indicating that the passive film on rebar is a highly disordered n-type semiconductor, with donor density (ND) in the order of 1026 m?3. After adding chloride ions (Cl? wt%<0.2%) in system solutions, the M-S plot slopes significantly de-creased and ND increased, suggesting that chloride ion will cause passive film corrosion and breakdown. The M-S plots of the passive film on rebar electrodes embedded in concrete were similar to those immersed in simulated system solution. However, ND of those in concrete with mineral admixtures tended to be a little smaller, indicating that introducing proper quantity admixtures into concrete could make the rebar passive film have a thicker space-charge layer and therefore a thicker passive film layer. 展开更多
关键词 钢筋电极 钝化膜 矿物材料 混凝土 电化学研究 导电性能
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Prospectivity modeling of porphyry copper deposits: recognition of efficient mono-and multi-element geochemical signatures in the Varzaghan district, NW Iran 被引量:1
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作者 Reza Ghezelbash Abbas Maghsoudi Mehrdad Daviran 《Acta Geochimica》 EI CAS CSCD 2019年第1期131-144,共14页
The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In this study we identified mono-and multi-el... The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In this study we identified mono-and multi-element geochemical anomalies associated with Cu–Au–Mo–Bi mineralization in the central parts of the Varzaghan district by applying the concentration–area fractal method. After mono-element geochemical investigations, principal component analysis was applied to ten selected elements in order to acquire a multi-element geochemical signature based on the mineralization-related component. Quantitative comparisons of the obtained fractal-based populations were carried out in accordance with known Cu occurrences using Student's t-values. Then,significant mono-and multi-element geochemical layers were separately combined with related geologic and structural layers to generate prospectivity models, using the fuzzy GAMMA approach. For quantitative evaluation of the effectiveness of different geochemical signatures in final prospectivity models, a prediction-area plot was adapted. The results show that the multi-element geochemical signature of principal component one(PC1) is more effective than mono-element layers in delimiting exploration targets related to porphyry Cu deposits. 展开更多
关键词 GEOCHEMICAL signature Concentration–area(C–A) fractal Principal component analysis(PCA) student’s t-value Fuzzy mineral prospectivity modeling(MPM) Prediction–area(P–A) plot
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IMPROVEMENT OF THE PLOT METHOD OF FATIGUE LIFE PREDICTION FORMULA
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作者 Liu Yilun Yao Wei(College of Mechanical and Electrical Engineering,Central South University of Technology, Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1998年第1期54-57,共4页
IMPROVEMENTOFTHEPLOTMETHODOFFATIGUELIFEPREDICTIONFORMULA*LiuYilunYaoWei(ColegeofMechanicalandElectricalEngin... IMPROVEMENTOFTHEPLOTMETHODOFFATIGUELIFEPREDICTIONFORMULA*LiuYilunYaoWei(ColegeofMechanicalandElectricalEngineering,CentralSou... 展开更多
关键词 FATIGUE LIFE PREDICTION the plot METHOD Weibull sN curve
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XRD Studies on Nano Crystalline Ceramic Superconductor PbSrCaCuO at Different Treating Temperatures 被引量:1
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作者 V. S. Vinila Reenu Jacob +5 位作者 Anusha Mony Harikrishnan G. Nair Sheelakumari Issac Sam Rajan Anitha S. Nair Jayakumari Isac 《Crystal Structure Theory and Applications》 2014年第1期1-9,共9页
High-temperature superconductivity in ceramic oxides is a new technology in which advances are occurring at a rapid pace. Here, the author describes some properties of a new nano crystalline ceramic Type II supercondu... High-temperature superconductivity in ceramic oxides is a new technology in which advances are occurring at a rapid pace. Here, the author describes some properties of a new nano crystalline ceramic Type II superconductor, PbSrCaCuO. Type II superconductors are usually made of metal alloys or complex oxide ceramics. The PSCCO perovskite phase structure was prepared by the conventional solid state reaction technique. In order to show the viability of the proposed method, super-conducting powder was prepared in special furnace. The sample was analyzed by X-ray Diffraction (XRD), Particle size determination, SEM and EDX. The comparison of XRD results with JCPDS files confirmed the orthorhombic structure of the sample with a ≠ b ≠ c and α = β = γ = 90°. Scanning electron microscopy (SEM) studies revealed that its particle size is in the nanometer range. It also confirmed the calculated value of particle size from Debye Scherrer’s formula. EDX spectrum shows the elements of the sample. X-ray instrumental peak broadening analysis was used to evaluate the size and lattice strain by the Williamson-Hall Plot method. 展开更多
关键词 Lead sTRONTIUM Calcium Copper Oxide (PsCCO) XRD sEM EDX DEBYE scherrer’s Formula INsTRUMENTAL BROADENING Williamson-Hall plot Method
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On the Tension in Kate Chopin’s Desiree’s Baby
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作者 HUANG Meng-si 《Journal of Literature and Art Studies》 2022年第7期712-715,共4页
Kate Chopin’s famous short story Desiree’s Baby attracts a large number of readers with its dramatic ending and thematic implication.The love and hate of Armand,the sharp contrast between L’Abri manor and Valmonde ... Kate Chopin’s famous short story Desiree’s Baby attracts a large number of readers with its dramatic ending and thematic implication.The love and hate of Armand,the sharp contrast between L’Abri manor and Valmonde plantation and the twists and turns of the plot form the tension beauty of this story.In order to further explore Desiree’s Baby,this paper interprets the emotional tension,image tension and plot tension in the short story.It further explores the thematic implication and artistic beauty of the novel,and reveals Chopin’s criticism of racism. 展开更多
关键词 desiree’s baby emotional tension image tension plot tension
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Extraction Properties of Calix[4]arenes towards Sulphonated Dyes
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作者 Muhammad Israr Faiza Faheem +6 位作者 Fozia T. Minhas Asma Rauf Saba Rauf M. Raza Shah Fazal Rahim Kiramat Shah M. I. Bhanger 《American Journal of Analytical Chemistry》 2016年第2期219-232,共14页
Extraction of sulphonated dyes through supramolecular interaction with calix[4]arene derivatives is being presented here. The selectivity of calixarene derivatives namely piperidine derivative of calix[4]arene (calix-... Extraction of sulphonated dyes through supramolecular interaction with calix[4]arene derivatives is being presented here. The selectivity of calixarene derivatives namely piperidine derivative of calix[4]arene (calix-1), 1-methyl piperazine derivative of calix[4]arene (calix-2), and di-methyl amine derivative of calix[4]arene (calix-3) were evaluated initially against reactive red 2 (RR-2), acid black (AB), reactive blue 19 (B-19) and synthetic dye (D-2) by liquid-liquid extraction experiment. The results showed that the above three calixarenes possess excellent complexation abilities toward the selected dyes. The stoichiometric ratio for the calixarene derivatives and dyes was estimated through Job’s plot, whereas Hildebrand-Benesi equation was used to calculate formation constant (K<sub>s</sub>) and molar absorptivity (Δε) of complexes. The binding association (K<sub>a</sub>) and dissociation (K<sub>d</sub>) constants were calculated by Scatchard plot additionally to further support the complexation data obtained from Hildebrand-Benesi equation. Conversely association constants from, both Hildebrand-Benesi equation and Scatchard plot i.e. K<sub>s</sub> and K<sub>a</sub> favor strong binding interaction between calix-1: D-2, calix-2: B-19, and calix-3: AB complexes. Thus present study adeptly supports the complexation of calixarene derivatives for sulfonated dyes. 展开更多
关键词 Calixarene Derivative COMPLEXATION Job’s plot Hildebrand and Benesi Equation Association Constant
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X-Ray Diffraction Analysis of Nano Crystalline Ceramic PbBaTiO<sub>3</sub>
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作者 V. S. Vinila Reenu Jacob +6 位作者 Anusha Mony Harikrishnan G. Nair Sheelakumari Issac Sam Rajan Anitha S. Nair D. J. Satheesh Jayakumari Isac 《Crystal Structure Theory and Applications》 2014年第3期57-65,共9页
X-ray crystallography is concerned with discovering and describing the crystal structure. High-temperature superconductivity in ceramic oxides is a new technology in which advances are occurring at a rapid pace. Here,... X-ray crystallography is concerned with discovering and describing the crystal structure. High-temperature superconductivity in ceramic oxides is a new technology in which advances are occurring at a rapid pace. Here, the author describes some properties of a new nano crystalline ceramic type II superconductor, PbBaTiO. Type II superconductors are usually made of metal alloys or complex oxide ceramics. The PBT perovskite phase structure was prepared by the conventional solid state reaction technique. The sample was analyzed by X-ray Diffraction (XRD), Particle size determination, SEM and EDX. The comparison of XRD results with JCPDS files confirmed the tetragonal structure of the sample with a = b ≠ c and α = β = γ = 90°. Scanning electron microscopy (SEM) studies revealed that its particle size was in the nanometer range. It also confirmed the calculated value of particle size from Debye Scherrer’s formula. EDX spectrum shows the elements of the sample. X-ray instrumental peak broadening analysis was used to evaluate the size and lattice strain by the Williamson-Hall Plot method. 展开更多
关键词 Lead Barium TITANATE (PBT) XRD sEM EDX DEBYE scherrer’s Formula Instrumental BROADENING Williamson-Hall plot Method
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Ceramic Nanocrystalline Superconductor Gadolinium Barium Copper Oxide (GdBaCuO) at Different Treating Temperatures
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作者 V. S. Vinila Reenu Jacob +6 位作者 Anusha Mony Harikrishnan G. Nair Sheelakumari Issac Sam Rajan Anitha S. Nair D. J. Satheesh Jayakumari Isac 《Journal of Crystallization Process and Technology》 2014年第3期168-176,共9页
With the discovery of high-TC superconducting materials like Yttrium Barium Cupric Oxide, Bismuth Strontium Calcium Copper Oxide and Thallium Calcium Barium Copper Oxide, tremendous interest has developed over the pas... With the discovery of high-TC superconducting materials like Yttrium Barium Cupric Oxide, Bismuth Strontium Calcium Copper Oxide and Thallium Calcium Barium Copper Oxide, tremendous interest has developed over the past two years in understanding these materials as well as utilizing them in a variety of applications. The thin films of these materials are expected to play an important role in the area of microelectronics, especially for interconnects in integrated circuits, Josephson junctions, magnetic field sensors and optical detectors. Here, the authors designed a new nanocrystalline ceramic type II high-TC superconductor, Gadolinium Barium Copper Oxide (GdBaCuO/GBCO). The GBCO perovskite phase structure was prepared by the conventional solid state thermochemical reaction technique involving mixing, milling, calcination and sintering. In GBCO system, the method for controlling microstructure and superconducting state is related to oxygen content consideration because small changes in oxygen concentration can often?lead to huge change in Tc. In order to show the viability of the proposed method, super-conducting powder was prepared in special furnace. The sample was analyzed by X-Ray Diffraction (XRD), an indispensible non-destructive tool for structural materials characterization and quality control which makes use of the Debye-Scherrer method. The comparison of XRD results with JCPDS files confirmed the orthorhombic structure of the sample. Micro-structural features are studied using Scanning Electron Microscopy (SEM) which revealed that its particle size is in the nanometer range. It also confirmed the calculated value of particle size from Debye Scherrer’s formula. EDX plot shows the presence of all the constituents. X-ray instrumental peak broadening analysis was used to evaluate the size and lattice strain by the Williamson-Hall Plot method. 展开更多
关键词 GADOLINIUM BARIUM Copper Oxide (GBCO) NANOCRYsTALLINE XRD sEM EDX DEBYE scherrer’s Formula Instrumental Broadening Williamson-Hall plot Method
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Studies on Nano Crystalline Ceramic Superconductor LaZrYBaCa<sub>2</sub>Cu<sub>3</sub>O<sub>11</sub>at Three Different Temperatures
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作者 Anitha S. Nair Vinila V. S. +6 位作者 Sheelakumari Issac Reenu Jacob Anusha Mony Harikrishnan G. Nair Sam Rajan Satheesh D. J. Jayakumari Isac 《Journal of Crystallization Process and Technology》 2014年第2期126-133,共8页
The high temperature superconductors are ceramic materials with layers of Copper-oxide spaced by layers containing Barium and other atoms. The Yttrium compound is somewhat unique in that it has a regular crystal struc... The high temperature superconductors are ceramic materials with layers of Copper-oxide spaced by layers containing Barium and other atoms. The Yttrium compound is somewhat unique in that it has a regular crystal structure while the Lanthanum version is classified as a solid solution. The Yttrium compound is often called the 1-2-3 superconductor because of the ratios of its constituents. Lanthanum Zirconium Yttrium Barium Calcium Copper Oxide (LaZrYBaCaCuO) was prepared by the usual solid state reaction method. In order to show the viability of the proposed method, super-conducting powder was prepared in special furnace. The sample was analyzed by X-ray Diffraction (XRD), Particle size determination, SEM and EDX. The comparison of XRD results with JCPDS files confirmed the orthorhombic structure of the sample with a ≠ b ≠ c and α = β = γ = 90°. Scanning Electron Microscopy (SEM) studies revealed that its particle size is in the nanometer range. It also confirmed the calculated value of particle size from Debye Scherrer’s formula. EDX spectrum shows the elements of the sample. X-ray instrumental peak broadening analysis was used to evaluate the size and lattice strain by the Williamson-Hall Plot method. 展开更多
关键词 Lanthanum Zirconium Yttrium Barium Calcium Copper Oxide (LaZrYBaCaCuO) XRD sEM EDX DEBYE scherrer’s Formula INsTRUMENTAL BROADENING Williamson-Hall plot Method
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New Bioactive Molecules with Potential Antioxidant Activity from Various Extracts of Wild Edible Gelam Mushroom (<i>Boletus</i>spp.)
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作者 M. H. M. Y. Yuswan Jameel R. Al-Obaidi +3 位作者 A. Rahayu S. Sahidan F. Shazrul D. Fauzi 《Advances in Bioscience and Biotechnology》 2015年第4期320-329,共10页
Boletus spp. is a wild edible Gelam mushroom, which is only available at coastal area of Bachok, Kelantan. Locals have used this mushroom as a food source and as a traditional medicine. In this study, antioxidants wer... Boletus spp. is a wild edible Gelam mushroom, which is only available at coastal area of Bachok, Kelantan. Locals have used this mushroom as a food source and as a traditional medicine. In this study, antioxidants were extracted using Mili-Q water and methanol. Extraction of 1.0 g of Boletus spp. mushroom pileus and stipe by water produced 0.22 ± 0.09 g and 0.3 ± 0.07 g of total aqueous soluble extracts, respectively. Methanol extraction of 1.0 g Boletus spp. mushroom pileus and stipe produced 0.31 ± 0.08 mg and 0.37 ± 0.05 mg of total methanol soluble extracts, respectively. DPPH assay has been used to determine the value of antioxidant efficiency of each extracts. DPPH assay revealed that the EC50 value of pileus aqueous soluble extract and both pileus and stipe methanol soluble extracts were 1.2 mg/ml. The EC50 value of stipe aqueous soluble extracts was 1.4 mg/ml. The EC50 value of ascorbic acid, an antioxidant control was 0.5 mg/ml. Liquid chromatography- DPPH (LC-DPPH) assay combined with Quadrupole Time-of-flight Mass Spectrometry (QTOF-MS) analysis of 3:2 ratio methanol and water extract has detected 43 antioxidant compounds that were involved in the reduction of DPPH. To identify these compounds, SIMCA 3.0 software that consists of PCA, OPLS-DA and s-plot analyses had been used. PCA analysis had shown the antioxidant activity from sample on DPPH as 73.6%. This antioxidant activity confirmed by OPLS-DA analysis had shown the variability between sample and control as 99.6% with 99.3% prediction. S-plot selection had shown ten antioxidant compounds significantly involved in the DPPH assay. Four of these compounds were identified by the METLIN and NIST databases. The antioxidant metabolites were 2,4,6-trimethylacetophenone imine, glutamyl tryptophan, azatadine and lithocholic acid glycine conjugate. In conclusion, this study revealed that Boletus spp. mushroom is rich with natural antioxidants, which are potentially useful for multiple nutritional and health applications. 展开更多
关键词 BOLETUs DPPH EC50 CHEMOMETRIC QTOF PCA OPLs-DA and s-plot
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Time-Frequency and Nonlinear Analysis of Tidal Data Observed on the Kuroshio Path
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作者 Kenta Kirimoto 《International Journal of Modern Nonlinear Theory and Application》 2016年第4期147-159,共13页
The tidal data of Kushimoto and Uragami on flow path of Kuroshio from 2004 to 2005 are investigated and discussed by time-frequency methods and nonlinear methods in this paper. These analyzing methods based on mathema... The tidal data of Kushimoto and Uragami on flow path of Kuroshio from 2004 to 2005 are investigated and discussed by time-frequency methods and nonlinear methods in this paper. These analyzing methods based on mathematical science show us new findings about the tidal motion observed on Kuroshio flow path. On the time-frequency analysis, 12 hours component and 24 hours component swing during the period of 350 hours and 320 hours respectively. However, any remarkable differences or changes depending on Kuroshio flow path weren’t seen on the result of time-frequency analysis. On the nonlinear analysis, a periodical structure has seen on the mutual information of tidal difference data, while Kuroshio flow is stable. In addition, the mutual information showed a characteristic of randomness and irregularity, while Kuroshio flow is unstable. The important results brought us a new finding such as classification of tidal motion regardless of the flow path of Kuroshio. 展开更多
关键词 Wavelet Transform Lorenz’s plot Mutual Information Time Development PERIODICITY IRREGULARITY Classification
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