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Understanding Pseudocapacitance Mechanisms by Synchrotron X-ray Analytical Techniques 被引量:1
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作者 Pei Tang Wuyang Tan +7 位作者 Guangyang Deng Yunting Zhang Shan Xu Qijun Wang Guosheng Li Jian Zhu Qingyun Dou Xingbin Yan 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期312-331,共20页
Pseudocapacitive materials that store charges via reversible surface or near-surface faradaic reactions are capable of overcoming the capacity limitations of electrical double-layer capacitors.Revealing the structure... Pseudocapacitive materials that store charges via reversible surface or near-surface faradaic reactions are capable of overcoming the capacity limitations of electrical double-layer capacitors.Revealing the structure–activity relationship between the microstructural features of pseudocapacitive materials and their electrochemical performance on the atomic scale is the key to build high-performance capacitor-type devices containing ideal pseudocapacitance effect.Currently,the high brightness(flux),and spectral and coherent nature of synchrotron X-ray analytical techniques make it a powerful tool for probing the structure–property relationship of pseudocapacitive materials.Herein,we report a comprehensive and systematic review of four typical characterization techniques(synchrotron X-ray diffraction,pair distribution function[PDF]analysis,soft X-ray absorption spectroscopy,and hard X-ray absorption spectroscopy)for the study of pseudocapacitance mechanisms.In addition,we offered significant insights for understanding and identifying pseudocapacitance mechanisms(surface redox pseudocapacitance,intercalation pseudocapacitance,and the extrinsic pseudocapacitance phenomenon in battery materials)by combining in situ hard XAS and electrochemical analyses.Finally,a perspective for further depth of understanding into the pseudocapacitance mechanism using synchrotron X-ray analytical techniques is proposed. 展开更多
关键词 in situ experiments pseudocapacitive materials structure-property relationship synchrotron X-ray analytical techniques
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Determination of Iron(Ⅱ), Iron(Ⅲ) and Total Iron in Some β -Thalassemia Patients Using Different Analytical Techniques
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作者 Nabil Fakhre Dashty Ali 《Journal of Environmental Science and Engineering(B)》 2013年第5期304-307,共4页
There are many well-known analytical methods for determination of iron(Ⅱ) and iron(Ⅲ). Among these methods: Gravimetric, titrimetric, potentiometric, conductometric and batch and flow-injection spectrophotometr... There are many well-known analytical methods for determination of iron(Ⅱ) and iron(Ⅲ). Among these methods: Gravimetric, titrimetric, potentiometric, conductometric and batch and flow-injection spectrophotometric methods. In present study, two batch spectrophotometric, atomic absorption spectrometric and biolabo kit methods have been used for determination of iron(Ⅱ), iron(Ⅲ) and total iron. The present methods have the advantages of high sensitivity, low cost reagent, low operation cost, simplicity, speed and their applications for determination of iron(Ⅱ) and iron(Ⅲ) in some serum samples of normal human and fl-thalasemia patients in Erbil city. For the first time especially in Erbil city attempts were made to use zero, first and second derivative spectra to identify the serum samples of some β-thallasemia patients from the normal human serum samples due to the appearance and resolution of peaks in both cases. 展开更多
关键词 Determination IRON β-thalassemia patients different analytical techniques.
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Recent Advances in the Analytical Techniques for PFASs and Corresponding Intermediates During Their Chemical Decomposition
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作者 LIU Fuyu KANG Tingshuo +3 位作者 HAN Bin ZHANG Qingzhe YIN Yongguang CAI Yong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2023年第3期361-369,共9页
Per-and polyfluoroalkyl substances(PFASs)have been restricted from production and consumption in many countries due to their persistence and biological toxicity.With the development of removal technologies,the require... Per-and polyfluoroalkyl substances(PFASs)have been restricted from production and consumption in many countries due to their persistence and biological toxicity.With the development of removal technologies,the requirement on the detection of different kinds of PFASs and their derivates is increasing.A suitable analytical method is the prerequisite and basis for the study of the degradation of PFASs.As various analytical methods have been reported,questions about which one is more suitable have arisen.It is a right time to summarize the past and suggest the future.In this paper,we summarized and discussed the analytical methods applied in the chemical degradation of PFASs.We also proposed the current problems and discussed the future directions in this field. 展开更多
关键词 Per-and polyfluoroalkyl substance(PFAS) analytical technique Decomposition intermediate
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An overview of electrochemical,non-electrochemical and analytical approaches for studying corrosion in magnesium and its alloys
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作者 Arash Fattah-Alhosseini Minoo Karbasi +2 位作者 Razieh Chaharmahali Abdelhameed Fardosi Mosab Kaseem 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第9期3516-3542,共27页
Corrosion is a pervasive phenomenon affecting materials across a multitude of scales,from the atomic to the macroscopic.This review paper presents a comprehensive examination of the methodologies employed in the analy... Corrosion is a pervasive phenomenon affecting materials across a multitude of scales,from the atomic to the macroscopic.This review paper presents a comprehensive examination of the methodologies employed in the analysis of magnesium corrosion,including electrochemical,non-electrochemical and analytical approaches,emphasizing the need for a diverse array of analytical tools to understand the complex interplay between corrosion,microstructure,and the dissolution mechanisms of magnesium alloys.The research showcases the utility of specific tools like SEM/EDS and SKPFM for targeted site analysis,while XPS and FTIR provide a broader perspective on specimen surfaces.The paper also discusses the value of in-situ analysis techniques,which allow for the real-time observation of corrosion processes,offering a dynamic view of the emergence and evolution of corrosion products.These in-situ methods stand in contrast to ex-situ analyses,which only permit post-experimental evaluation.By highlighting the capabilities of various analytical tools,from those that reveal surface layer details to those that probe deeper structures,and from those that detect primary elements to those that trace minute quantities of impurities,this study underscores the intricate nature of corrosion and the critical role of advanced analytical techniques in fostering a deeper understanding of material degradation.The findings advocate for the increased application of in-situ analysis in magnesium corrosion research,as it provides a more immediate and accurate depiction of corrosion dynamics,potentially leading to more effective corrosion prevention and control strategies. 展开更多
关键词 Mg and its alloy Electrochemical test Non-electrochemical test analytical technique Corrosion behavior
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Plants’Steroidal Saponins‑A Review on Its Pharmacology Properties and Analytical Techniques 被引量:1
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作者 Sudha Porte Veenu Joshi +1 位作者 Kamal Shah Nagendra Singh Chauhan 《World Journal of Traditional Chinese Medicine》 CAS 2022年第3期350-385,共36页
The plant is a rich repository of useful secondary metabolites with profound medicinal potential.Saponins,one type of bioactive compound,are amphitheatric glycosides with one and more hydrophilic sugar and hydrophobic... The plant is a rich repository of useful secondary metabolites with profound medicinal potential.Saponins,one type of bioactive compound,are amphitheatric glycosides with one and more hydrophilic sugar and hydrophobic steroidal and terpenoid part.The former is known as steroidal saponin,and the latter is called terpenoid saponins.Steroidal saponin is mostly distributed among monocotyledon families such as Asparagaceae,Amaryllidaceae,Dioscoreaceae,Smilacaceae,and Liliaceae.Even though it is unusual,it could also be detected to some extent by dicotyledonous angiosperms,such as Plantaginaceae,Zygophyllaceae,Fabaceae,Asteraceae,and Solanaceae.It exhibits diverse pharmacological ability including antimicrobic,anti‑inflammatory,cAMP phosphodiesterase inhibitory,antiadipogenic,bactericide,cardioprotective,antitumor,antidiabetic,cytotoxic activity,antifungal,antiviral,antioxidant,and hepatoprotective.Steroidal saponin timosaponin AIII from Anemarrhena asphodeloides has been found to possess antitumor activity.Diosgenin,another steroidal sapogenin,has the potential of preventing neurological diseases by affecting different signaling pathways,increasing bone formation,and increasing antithrombotic activity.Spicatoside A from Liriope platyphylla possesses anti‑inflammatory,antiasthma,and antiosteoclastogenic activities.TTB2 from Trillium tschonoskii exhibits anticancer potential.The cell cycle arrest and ROS‑dependent autophagy are induced by polyphyllin I.These diverse biological activities of steroidal saponins are attributed to the variability of their structural features.Analysis of steroidal saponins in plant materials mainly utilizes classically and advances thin layer chromatography(TLC)on normal and reverses‑phase(high‑performance thin‑layer chromatography,densitometric TLC),gas chromatography,LC,UPLC,ultra‑high‑performance liquid chromatography(HPLC),supercritical fluid chromatography,and HPLC coupled to ultraviolet detector and diode array detector.HPLC coupled with MS and Nuclear magnetic resonance is used for online identification of separated saponins.The present review aims to furnish a comprehensive account of the recent advances in analytical methods of determination and medicinal applications of steroidal saponins. 展开更多
关键词 Steroidal SAPONINS GLYCOSIDES ANTITUMOUR ANTIOXIDANT analytical techniques
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Probing the interaction at nano-bio interface using synchrotron radiation-based analytical techniques 被引量:1
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作者 Bing Wang Weiyue Feng +1 位作者 Zhifang Chai Yuliang Zhao 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第5期768-779,共12页
Understanding the interactions of nanomaterials(NMs) with biomolecules, organelles, cells, and organic tissues at the nano-bio interface can offer important information for their uptake, distribution, translocation, m... Understanding the interactions of nanomaterials(NMs) with biomolecules, organelles, cells, and organic tissues at the nano-bio interface can offer important information for their uptake, distribution, translocation, metabolism and degradation in vitro and in vivo, which can help to precisely tune and design "smart" NMs for biomedical applications. However, probing the interactions at the nano-bio interface, which generally requires dedicated analytical methods and tools, is remarkably complicated due to the dynamically changed nature of the nano-bio interface. Because of the advantages of high spatial resolution, high sensitivity, excellent accuracy, low matrix effects and non-destructiveness, synchrotron radiation(SR)-based analytical techniques have become extremely valuable tools. Herein, we present a comprehensive overview of SR-based techniques for the visualized study of NMs at cellular and subcellular interfaces and their transformation in vitro; the exploration of biodistribution, translocation, metabolism and degradation of NMs in vivo; and clarification of the molecular mechanisms of NMs' reactions with biomolecules. Rapid development of advanced light source means that in situ, real-time analysis of NMs at the nano-bio interface will be achieved. 展开更多
关键词 nano-bio interface synchrotron-radiation-based analytical techniques interaction
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A review on pharmacological and analytical aspects of diosgenin:a concise report 被引量:4
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作者 Kanika PATEL Manoj GADEWAR +1 位作者 Vijay TAHILYANI Dinesh Kumar PATEL 《Natural Products and Bioprospecting》 CAS 2012年第2期46-52,共7页
Diosgenin is a steroidal sapogenin found in plants such as Dioscorea nipponoca,Solanum incanum,Solanum xanthocarpum and Trigonella foenum graecum.Diosgenin,biologically active phytochemicals have been used for the tre... Diosgenin is a steroidal sapogenin found in plants such as Dioscorea nipponoca,Solanum incanum,Solanum xanthocarpum and Trigonella foenum graecum.Diosgenin,biologically active phytochemicals have been used for the treatment of various types of disorder such as leukemia,inflammation,hypercholesterolemia and cancer.It is also able to prevent bone loss to the same extent as that of oestrogen.It is a typical initial intermediate for synthesis of steroidal compounds,oral contraceptives and sex hormones.Dioscorea,Costus and Trigonella are mainly used for the production of diosgenin.On the basis of literature survey it divulges that diosgenin has very impressive pharmacological profile and could be used as a medicine for the treatment of different types of disorders in the future.Thus,the present work aims to provide collective information in concern with its pharmacological activity and phytoanalytical techniques.This review will be beneficial to researches for the development of an alternative method for the treatment of innumerable diseases from diosgenin. 展开更多
关键词 analytical techniques cancer DIOSGENIN pharmacological activity plant source seperation techniques
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Analytical calculation of electromagnetic, torque for surface mounted permanent magnet brushless motors 被引量:2
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作者 杜世勤 章跃进 江建中 《Journal of Shanghai University(English Edition)》 CAS 2007年第3期309-313,共5页
With the air gap magnetic field distribution of surface mounted permanent magnet (PM) motors obtained using an analytical technique, the instantaneous electromagnetic torque and its corresponding components are inve... With the air gap magnetic field distribution of surface mounted permanent magnet (PM) motors obtained using an analytical technique, the instantaneous electromagnetic torque and its corresponding components are investigated with the Maxwell stress tensor method. Accurate results can easily be achieved using the proposed method without using the tedious finite element analysis (FEA). In this paper, the electromagnetic torque of a surface mounted PM motor with two phases energized is decomposed into four torque components. This technique is useful not only for the design and optimization of the permanent magnet motor, but also for the choice of control strategy. 展开更多
关键词 surface mounted permanent magnet motors air gap magnetic field analytical technique electromagnetic torque.
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Recent Progress in Interfacial Dipole Engineering for Perovskite Solar Cells 被引量:3
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作者 Yinyi Ma Jue Gong +1 位作者 Peng Zeng Mingzhen Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期260-286,共27页
Design and modification of interfaces have been the main strategies in developing perovskite solar cells(PSCs). Among the interfacial treatments, dipole molecules have emerged as a practical approach to improve the ef... Design and modification of interfaces have been the main strategies in developing perovskite solar cells(PSCs). Among the interfacial treatments, dipole molecules have emerged as a practical approach to improve the efficiency and stability of PSCs due to their unique and versatile abilities to control the interfacial properties. Despite extensive applications in conventional semiconductors, working principles and design of interfacial dipoles in the performance/stability enhancement of PSCs are lacking an insightful elucidation. In this review, we first discuss the fundamental properties of electric dipoles and the specific roles of interfacial dipoles in PSCs. Then we systematically summarize the recent progress of dipole materials in several key interfaces to achieve efficient and stable PSCs. In addition to such discussions, we also dive into reliable analytical techniques to support the characterization of interfacial dipoles in PSCs. Finally, we highlight future directions and potential avenues for research in the development of dipolar materials through tailored molecular designs. Our review sheds light on the importance of continued efforts in this exciting emerging field, which holds great potential for the development of high-performance and stable PSCs as commercially demanded. 展开更多
关键词 Perovskite solar cells Interfacial dipoles analytical techniques
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Studies on the Quality of Recombinant Human GrowthHormone
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作者 张培培 杨化新 +2 位作者 徐康森 李湛君 闫安庄 《Journal of Chinese Pharmaceutical Sciences》 CAS 1996年第1期20-27,共8页
The quality of r-hGH has been appraised by various analytical techniques in-cluding SDS-PAGE, IEF. HPSEC, RP-HPLC, ELISA. Dot-immunobinding assay, DIG labeling DNAhybridization and bioassay The results shouwed that th... The quality of r-hGH has been appraised by various analytical techniques in-cluding SDS-PAGE, IEF. HPSEC, RP-HPLC, ELISA. Dot-immunobinding assay, DIG labeling DNAhybridization and bioassay The results shouwed that the quality of the domestic products of r-hGHreached the international level. 展开更多
关键词 R-HGH Quality control analytical techniques
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Determination of Heroin Based on Analyte Pulse Perturbation to an Oscillating Chemical Reaction 被引量:4
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作者 RENJie GAOJin-zhang +5 位作者 Suo-nan ZHAOGuo-hu YANGWu LüDong-yu SUNKan-jun LIChong-yang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第5期534-538,共5页
A new analytical method is proposed for the determination of heroin based on a sequential perturbation caused by trace amounts of heroin in the Cu(Ⅱ)-catalyzed oscillating reaction between hydrogen peroxide and sodiu... A new analytical method is proposed for the determination of heroin based on a sequential perturbation caused by trace amounts of heroin in the Cu(Ⅱ)-catalyzed oscillating reaction between hydrogen peroxide and sodium thiocyanate in an alkaline medium with the aid of a continuous-flow stirred tank reactor(CSTR). The method relies on the linear relationship between the change in oscillation period of the system and the concentration of heroin, with a detecting limit of 4.0×10^(-7) mol/L. The calibration curve fits a linear equation very well when the concentration of heroin is in the range of 2.0×10^(-6)_1.2×10^(-5) mol/L(r=0.9971). This method features good precision(RSD=0.98%). The influences of temperature, injection point, flow rate and reaction variables on the oscillation period were investigated in detail and a possible mechanism of the performance of heroin in the Cu(Ⅱ)-catalyzed oscillating reaction system is also discussed. The proposed method opens a new avenue for the determination of heroin. 展开更多
关键词 Cu(Ⅱ)-catalyzed oscillating reaction HEROIN Analyte pulse perturbation technique(APP) Mechanism Continuous-flow stirred tank reactor(CSTR).
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Earth-moon Trajectory Optimization Using Solar Electric Propulsion 被引量:2
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作者 Gao Yang 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第5期452-463,共12页
The optimization of the Earth-moon trajectory using solar electric propulsion is presented. A feasible method is proposed to optimize the transfer trajectory starting from a low Earth circular orbit (500 km altitude... The optimization of the Earth-moon trajectory using solar electric propulsion is presented. A feasible method is proposed to optimize the transfer trajectory starting from a low Earth circular orbit (500 km altitude) to a low lunar circular orbit (200 km altitude). Due to the use of low-thrust solar electric propulsion, the entire transfer trajectory consists of hundreds or even thousands of orbital revolutions around the Earth and the moon. The Earth-orbit ascending (from low Earth orbit to high Earth orbit) and lunar descending (from high lunar orbit to low lunar orbit) trajectories in the presence of J2 perturbations and shadowing effect are computed by an analytic orbital averaging technique. A direct/indirect method is used to optimize the control steering for the trans-lunar trajectory segment, a segment from a high Earth orbit to a high lunar orbit, with a fixed thrust-coast-thrust engine sequence. For the trans-lunar trajectory segment, the equations of motion are expressed in the inertial coordinates about the Earth and the moon using a set of nonsingular equinoctial elements inclusive of the gravitational forces of the sun, the Earth, and the moon. By way of the analytic orbital averaging technique and the direct/indirect method, the Earth-moon transfer problem is converted to a parameter optimization problem, and the entire transfer trajectory is formulated and optimized in the form of a single nonlinear optimization problem with a small number of variables and constraints. Finally, an example of an Earth-moon transfer trajectory using solar electric propulsion is demonstrated. 展开更多
关键词 trajectory optimization solar electric propulsion analytic orbital averaging technique direct/indirect method
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An object correlation and maneuver detection approach for space surveillance 被引量:2
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作者 Jian Huang Wei-Dong Hu +1 位作者 Qin xin Xiao-Yong Du 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第10期1402-1416,共15页
Object correlation and maneuver detection are persistent problems in space surveillance and maintenance of a space object catalog. We integrate these two prob- lems into one interrelated problem, and consider them sim... Object correlation and maneuver detection are persistent problems in space surveillance and maintenance of a space object catalog. We integrate these two prob- lems into one interrelated problem, and consider them simultaneously under a sce- nario where space objects only perform a single in-track orbital maneuver during the time intervals between observations. We mathematically formulate this integrated sce- nario as a maximum a posteriori (MAP) estimation. In this work, we propose a novel approach to solve the MAP estimation. More precisely, the corresponding posterior probability of an orbital maneuver and a joint association event can be approximated by the Joint Probabilistic Data Association (JPDA) algorithm. Subsequently, the ma- neuvering parameters are estimated by optimally solving the constrained non-linear least squares iterative process based on the second-order cone programming (SOCP) algorithm. The desired solution is derived according to the MAP criterions. The per- formance and advantages of the proposed approach have been shown by both theoret- ical analysis and simulation results. We hope that our work will stimulate future work on space surveillance and maintenance of a space object catalog. 展开更多
关键词 celestial mechanics -- methods: analytical -- techniques miscellaneous-- surveys
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Performance evaluation of lunar penetrating radar onboard the rover of CE-3 probe based on results from ground experiments 被引量:4
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作者 Hong-Bo Zhang Lei Zheng +10 位作者 Yan Su Guang-You Fang Bin Zhou Jian-Qing Feng Shu-Guo Xing Shun Dai Jun-Duo Li Yi-Cai Ji Yun-Ze Gao Yuan Xiao Chun-Lai Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1633-1641,共9页
Lunar Penetrating Radar (LPR) onboard the rover that is part of the Chang'e-3 (CE-3) mission was firstly utilized to obtain in situ measurements about geological structure on the lunar surface and the thickness o... Lunar Penetrating Radar (LPR) onboard the rover that is part of the Chang'e-3 (CE-3) mission was firstly utilized to obtain in situ measurements about geological structure on the lunar surface and the thickness of the lunar regolith, which are key elements for studying the evolutional history of lunar crust. Because penetra- tion depth and resolution of LPR are related to the scientific objectives of this mission, a series of ground-based experiments using LPR was carried out, and results of the experimental data were obtained in a glacial area located in the northwest region of China. The results show that the penetration depth of the first channel antenna used for LPR is over 79 m with a resolution of 2.8 m, and that for the second channel antenna is over 50.8 m with a resolution of 17.1 cm. 展开更多
关键词 Moon -- techniques radar astronomy -- methods: analytical
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Flow of Eyring-Powell liquid due to oscillatory stretchable curved sheet with modified Fourier and Fick’s model
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作者 M.IMRAN Z.ABBAS M.NAVEED 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第10期1461-1478,共18页
This study deals with the features of the mass and heat transport mechanism by adopting a modified version of Fourier and Fick’s model known as the CattaneoChristov double diffusive theory.The time-dependent magnetoh... This study deals with the features of the mass and heat transport mechanism by adopting a modified version of Fourier and Fick’s model known as the CattaneoChristov double diffusive theory.The time-dependent magnetohydrodynamic(MHD)flow of the Eyring-Powell liquid across an oscillatory stretchable curved sheet in the presence of Fourier and Fick’s model is investigated.The acquired set of flow equations is transformed into the form of nonlinear partial differential equations(PDEs)by applying appropriate similarity variables.A convergent series solution to the developed nonlinear equations is accomplished with the help of an analytical approach,i.e.,the homotopy analysis method(HAM).The consequences of diverse parameters,including the dimensionless EyringPowell liquid parameter,the radius of curvature,the Schmidt/Prandtl numbers,the ratio of the oscillatory frequency of the sheet to its stretchable rate constant,the mass and thermal relaxation variables involved in the flow,and the heat and mass properties,are displayed through graphs and tables.It is noted from this study that the amplitude of the pressure distribution rises for the high parametric values of the Eyring-Powell parameter. 展开更多
关键词 oscillatory stretchable curved surface magnetohydrodynamic(MHD) Eyring-Powell liquid Cattaneo-Christov double diffusion analytical technique
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HOMOTOPY ANALYSIS METHOD: A NEW ANALYTICMETHOD FOR NONLINEAR PROBLEMS
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作者 廖世俊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第10期957-962,共6页
In this paper, the basic ideas of a new analytic technique, namely the Homotopy Analysis Method (HAM), are described. Different from perturbation methods, the validity of the HAM is independent on whether or not there... In this paper, the basic ideas of a new analytic technique, namely the Homotopy Analysis Method (HAM), are described. Different from perturbation methods, the validity of the HAM is independent on whether or not there exist small parameters in considered nonlinear equations. Therefore, it provides us with a powerful analytic tool for strongly nonlinear problems. A typical nonlinear problem is used as an example to verify the validity and the great potential of the HAM. 展开更多
关键词 nonlinear analytic technique strong nonlinearity HOMOTOPY TOPOLOGY
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Comparative Analysis for Different Mathematical Models in Electron Optics
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作者 Valentin Ivanov 《Journal of Chemistry and Chemical Engineering》 2014年第10期990-995,共6页
The comparative analysis of modem mathematical models for 3D problems in electron optics is presented. The new approach to solve the electron optics problems in three dimensions is presented. It is based on the princi... The comparative analysis of modem mathematical models for 3D problems in electron optics is presented. The new approach to solve the electron optics problems in three dimensions is presented. It is based on the principal ray method suggested by G. Grinberg in 1948. That perspective approach was not realized before for full three-dimensional electron optic systems, probably because of the complexity of its mathematical apparatus. We describe the analytical technique of the BEM (boundary element method) for the field evaluation, and 3rd order aberration expansion for the trajectory analysis. The first version of such computer code "OPTICS-3" and some results of numerical simulations with this code were presented. 展开更多
关键词 Electron optics aberration theory analytical technique boundary element method.
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Noise reduction methods in the analysis of near infrared lunar occultation light curves for high angular resolution measurements
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作者 Tapas Baug Thyagarajan Chandrasekhar 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2013年第11期1363-1380,共18页
A lunar occultation (LO) technique in the near-infrared (NIR) provides angular resolution down to milliarcseconds for an occulted source, even with ground- based 1 m class telescopes. LO observations are limited t... A lunar occultation (LO) technique in the near-infrared (NIR) provides angular resolution down to milliarcseconds for an occulted source, even with ground- based 1 m class telescopes. LO observations are limited to brighter objects because they require a high signal-to-noise ratio (S/N ~40) for proper extraction of angular diameter values. Hence, methods to improve the S/N ratio by reducing noise using Fourier and wavelet transforms have been explored in this study. A sample of 54 NIR LO light curves observed with the IR camera at Mt Abu Observatory has been used. It is seen that both Fourier and wavelet methods have shown an improvement in S/N compared to the original data. However, the application of wavelet transforms causes a slight smoothing of the fringes and results in a higher value for angular diameter. Fourier transforms which reduce discrete noise frequencies do not distort the fringe. The Fourier transform method seems to be effective in improving the S/N, as well as improving the model fit, particularly in the fainter regime of our sample. These methods also provide a better model fit for brighter sources in some cases, though there may not be a significant imorovement in S/N. 展开更多
关键词 methods: analytical -- techniques high angular resolution -- methods:lunar occultation -- infrared: stars -- stars: late type
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Cell softness reveals tumorigenic potential via ITGB8/AKT/glycolysis signaling in a mice model of orthotopic bladder cancer
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作者 Shi Qiu Yaqi Qiu +18 位作者 Linghui Deng Ling Nie Liming Ge Xiaonan Zheng Di Jin Kun Jin Xianghong Zhou Xingyang Su Boyu Cai Jiakun Li Xiang Tu Lina Gong Liangren Liu Zhenhua Liu Yige Bao Jianzhong Ai Tianhai Lin Lu Yang Qiang Wei 《Chinese Medical Journal》 SCIE CAS CSCD 2024年第2期209-221,共13页
Background:Bladder cancer,characterized by a high potential of tumor recurrence,has high lifelong monitoring and treatment costs.To date,tumor cells with intrinsic softness have been identified to function as cancer s... Background:Bladder cancer,characterized by a high potential of tumor recurrence,has high lifelong monitoring and treatment costs.To date,tumor cells with intrinsic softness have been identified to function as cancer stem cells in several cancer types.Nonetheless,the existence of soft tumor cells in bladder tumors remains elusive.Thus,our study aimed to develop a microbarrier microfluidic chip to efficiently isolate deformable tumor cells from distinct types of bladder cancer cells.Methods:The stiffness of bladder cancer cells was determined by atomic force microscopy(AFM).The modified microfluidic chip was utilized to separate soft cells,and the 3D Matrigel culture system was to maintain the softness of tumor cells.Expression patterns of integrinβ8(ITGB8),protein kinase B(AKT),and mammalian target of rapamycin(mTOR)were determined by Western blotting.Double immunostaining was conducted to examine the interaction between F-actin and tripartite motif containing 59(TRIM59).The stem-cell-like characteristics of soft cells were explored by colony formation assay and in vivo studies upon xenografted tumor models.Results:Using our newly designed microfluidic approach,we identified a small fraction of soft tumor cells in bladder cancer cells.More importantly,the existence of soft tumor cells was confirmed in clinical human bladder cancer specimens,in which the number of soft tumor cells was associated with tumor relapse.Furthermore,we demonstrated that the biomechanical stimuli arising from 3D Matrigel activated the F-actin/ITGB8/TRIM59/AKT/mTOR/glycolysis pathways to enhance the softness and tumorigenic capacity of tumor cells.Simultaneously,we detected a remarkable up-regulation in ITGB8,TRIM59,and phospho-AKT in clinical bladder recurrent tumors compared with their non-recurrent counterparts.Conclusions:The ITGB8/TRIM59/AKT/mTOR/glycolysis axis plays a crucial role in modulating tumor softness and stemness.Meanwhile,the soft tumor cells become more sensitive to chemotherapy after stiffening,that offers new insights for hampering tumor progression and recurrence. 展开更多
关键词 Soft tumor cells 3D Matrigel STEMNESS Non-muscle invasive bladder neoplasms Microfluidic analytical techniques
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A Review on Pharmacological and Analytical Aspects of Naringenin 被引量:33
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作者 Kanika Patel Gireesh Kumar Singh Dinesh Kumar Patel 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2018年第7期551-560,共10页
Flavonoids are a widely distributed group of phytochemicals having benzo-pyrone nucleus, and more than 4,000 different flavonoids have been described and categorized into flavonols, flavones, flavanones, isoflavones, ... Flavonoids are a widely distributed group of phytochemicals having benzo-pyrone nucleus, and more than 4,000 different flavonoids have been described and categorized into flavonols, flavones, flavanones, isoflavones, catechins and anthocyanidins. Flavonoids occurs naturally in fruits, vegetables, nuts, and beverages such as coffee, tea, and red wine, as well as in medical herbs. Flavonoids are responsible for the different colors of plant parts and are important constituents of the human diet. Flavanoids have different pharmacological activities, such as antioxidant, anti-allergic, antibacterial, anti-inflammatory, antimutagenic and anticancer activity. Naringenin belongs to the flavanones and is mainly found in fruits(grapefruit and oranges) and vegetables. Pharmacologically, it has anticancer, antimutagenic, anti-inflammatory, antioxidant, antiproliferative and antiatherogenic activities. Naringenin is used for the treatments of osteoporosis, cancer and cardiovascular diseases, and showed lipid-lowering and insulin-like properties. In the present review, detailed pharmacological and analytical aspects of naringenin have been presented, which revealed the impressive pharmacological profile and the possible usefulness in the treatment of different types of diseases in the future. The information provided in this communication will act as an important source for development of effective medicines for the treatment of various disorders. 展开更多
关键词 analytical techniques FLAVONOIDS NARINGENIN pharmacological activity PHYTOCONSTITUENTS
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