The microscopic response characteristics of nuclear magnetic resonance(NMR) are widely used for characterizing complex pore structures of rocks. Due to the prohibitive NMR experiment cost, numerical simulation was emp...The microscopic response characteristics of nuclear magnetic resonance(NMR) are widely used for characterizing complex pore structures of rocks. Due to the prohibitive NMR experiment cost, numerical simulation was employed as an alternative approach to verify some theoretical aspects of NMR responses. Firstly, the basic principles of pore-scale NMR simulation based on random-walk method(RWM) were introduced. The RWM-simulated results were benchmarked with the analytical results for an ideal spherical pore model. Then, the effects of two numerical parameters, namely diffusion radius and walk numbers, were studied on the simulation accuracy. The simulation method is then applied to various pore models with different pore sizes and pore shapes filled with different fluids to study the microscopic NMR response characteristics. The numerical experiments are useful for understanding and interpreting NMR measurements and the simulation code provides a numerical tool to perform pixel-based digital rock analysis.展开更多
Assisted by the bead pull technique,nonresonant perturbation theory is applied for measuring and tuning the field of the linac accelerating structure.The method is capable of making non-touching amplitude and phase me...Assisted by the bead pull technique,nonresonant perturbation theory is applied for measuring and tuning the field of the linac accelerating structure.The method is capable of making non-touching amplitude and phase measurements,real time mismatch feedback and field tuning.Some key considerations of the measurement system and of a C-band traveling-wave structure are discussed,and the bead pull measurement and the tuning of the C-band traveling-wave linac accelerating structure are presented at last.展开更多
OBJECTIVE： To provide existence of abnormal potential evidence for the Savda, we assessed host metabonomic responses and dynamic changes oc- curring in various diseases using 1H nuclear mag- netic resonance （NMR）-b...OBJECTIVE： To provide existence of abnormal potential evidence for the Savda, we assessed host metabonomic responses and dynamic changes oc- curring in various diseases using 1H nuclear mag- netic resonance （NMR）-based metabonomics. METHODS： Plasma samples taken from patients with complicated diseases with abnormal Savda （n= 140, including 35 cases each of diabetes, asthma, breast cancer, and cervical carcinoma） and from healthy controls （n=35） were analyzed by ~H NMR （600 MHz）, and the spectral profiles were analyzed by multivariate analysis using orthogonal projec- tion to latent structure with discriminant analysis. RESULTS： Supervised modeling of the data provid- ed very good discrimination between patients and healthy controls. Compared with ,the healthy controls, the patient groups with different disease con- ditions displayed similar metabolic changes, characterized by lower creatine, creatinine, lactate, and amino acid levels （including isoleucine, leucine, va- line, alanine, and 1-methylhistidine） and higher lip- id levels （very low-density lipoproteins and unsatu- rated lipids）. Additionally, cancer patients （breast and cervical） showed decreased myo-inositol, a-glucose, and 13-glucose, and increased pyruvate and carnitine in plasma. CONCLUSION： The data indicate that decreased ox- idative defense, liver function abnormalities, amino acid deficiencies, and energy metabolism disorders are common characteristics of complicated diseas- es, which may be related to the formation of abnor- mal Savda.展开更多
In order to suppress the fast decrease of the transfer efficiency of magnetic resonance coupled wireless power transfer system(MRCWPTS) with distance increase,this paper investigates the impact factors of the system t...In order to suppress the fast decrease of the transfer efficiency of magnetic resonance coupled wireless power transfer system(MRCWPTS) with distance increase,this paper investigates the impact factors of the system transfer efficiency and is,then formulates a new efficiency optimal control method based on frequency control.Based upon this control method two optimal control schemes are designed to achieve transfer efficiency control of the system.Simulations and experiments show that the proposed efficiency optimal control method can effectively stabilize the system transfer efficiency in a certain range so as to successfully solve the subtle issue of transfer efficiency variation with distance.展开更多
基金Project(265201248) supported by the Fundamental Research Funds for the Central Universities,ChinaProject(41172130) supported by the National Natural Science Foundation of China+2 种基金Project(2011ZX05014-001) supported by the Major State S&T Special Fund,ChinaProject(201205002) supported by the China Scholarship CouncilProject(2011D-5006-0305) supported by the China National Petroleum Co.Innovation Foundation,China
文摘The microscopic response characteristics of nuclear magnetic resonance(NMR) are widely used for characterizing complex pore structures of rocks. Due to the prohibitive NMR experiment cost, numerical simulation was employed as an alternative approach to verify some theoretical aspects of NMR responses. Firstly, the basic principles of pore-scale NMR simulation based on random-walk method(RWM) were introduced. The RWM-simulated results were benchmarked with the analytical results for an ideal spherical pore model. Then, the effects of two numerical parameters, namely diffusion radius and walk numbers, were studied on the simulation accuracy. The simulation method is then applied to various pore models with different pore sizes and pore shapes filled with different fluids to study the microscopic NMR response characteristics. The numerical experiments are useful for understanding and interpreting NMR measurements and the simulation code provides a numerical tool to perform pixel-based digital rock analysis.
基金supported by Program of Shanghai Subject Chief Scientist and Natural Science Foundation of China (key program) (Grant No. 08XD1405400)
文摘Assisted by the bead pull technique,nonresonant perturbation theory is applied for measuring and tuning the field of the linac accelerating structure.The method is capable of making non-touching amplitude and phase measurements,real time mismatch feedback and field tuning.Some key considerations of the measurement system and of a C-band traveling-wave structure are discussed,and the bead pull measurement and the tuning of the C-band traveling-wave linac accelerating structure are presented at last.
基金Supported by China National Natural Science Foundation Program (No.81160459)
文摘OBJECTIVE： To provide existence of abnormal potential evidence for the Savda, we assessed host metabonomic responses and dynamic changes oc- curring in various diseases using 1H nuclear mag- netic resonance （NMR）-based metabonomics. METHODS： Plasma samples taken from patients with complicated diseases with abnormal Savda （n= 140, including 35 cases each of diabetes, asthma, breast cancer, and cervical carcinoma） and from healthy controls （n=35） were analyzed by ~H NMR （600 MHz）, and the spectral profiles were analyzed by multivariate analysis using orthogonal projec- tion to latent structure with discriminant analysis. RESULTS： Supervised modeling of the data provid- ed very good discrimination between patients and healthy controls. Compared with ,the healthy controls, the patient groups with different disease con- ditions displayed similar metabolic changes, characterized by lower creatine, creatinine, lactate, and amino acid levels （including isoleucine, leucine, va- line, alanine, and 1-methylhistidine） and higher lip- id levels （very low-density lipoproteins and unsatu- rated lipids）. Additionally, cancer patients （breast and cervical） showed decreased myo-inositol, a-glucose, and 13-glucose, and increased pyruvate and carnitine in plasma. CONCLUSION： The data indicate that decreased ox- idative defense, liver function abnormalities, amino acid deficiencies, and energy metabolism disorders are common characteristics of complicated diseas- es, which may be related to the formation of abnor- mal Savda.
文摘In order to suppress the fast decrease of the transfer efficiency of magnetic resonance coupled wireless power transfer system(MRCWPTS) with distance increase,this paper investigates the impact factors of the system transfer efficiency and is,then formulates a new efficiency optimal control method based on frequency control.Based upon this control method two optimal control schemes are designed to achieve transfer efficiency control of the system.Simulations and experiments show that the proposed efficiency optimal control method can effectively stabilize the system transfer efficiency in a certain range so as to successfully solve the subtle issue of transfer efficiency variation with distance.
