The Antarctic ozone hole which was discovered in the mid 1980s has caused much attention from the scientists and politicians throughout the world.For the formation of the Antarctic ozone hole, most scientists believe ...The Antarctic ozone hole which was discovered in the mid 1980s has caused much attention from the scientists and politicians throughout the world.For the formation of the Antarctic ozone hole, most scientists believe that the man-made chemical materials such as CFCs etc. are main cause. On the other hand, the electrochemistry-dynamics theory presented by Wei (Guang Ming Daily Dec. 11 ,1990) two years ago has also caused some attention.In the paper the data of ozone, solar activity meteorology over Antarctica have been used for statistical analytical studies. Our results present some new evidence to support Wei's theory. However the influence of the human activities can never be slighted.展开更多
In this paper the analytical performance of the low-powered Ar microwave plasma torch atomic emission spectrometry(MPT-AES) was studied.The experimental results indicate that the analytical performance of low-powered ...In this paper the analytical performance of the low-powered Ar microwave plasma torch atomic emission spectrometry(MPT-AES) was studied.The experimental results indicate that the analytical performance of low-powered ArMPT-AES is satisfactory.展开更多
An explicit analytical solution is presented for unidirectionally coupled two Murali-Lakshmanan-Chua circuits exhibiting chaos synchronization in their dynamics. The transition of the system from an unsynchronized sta...An explicit analytical solution is presented for unidirectionally coupled two Murali-Lakshmanan-Chua circuits exhibiting chaos synchronization in their dynamics. The transition of the system from an unsynchronized state to a state of complete synchronization under the influence of the coupling parameter is observed through phase portraits obtained from the analytical solutions of the circuit equations characterizing the system.展开更多
This part of study represents the applied study;which is a continuation of the experimental study that was carried out in part 1 [1]<span "="">. The experimental study in part 1 focused on ev...This part of study represents the applied study;which is a continuation of the experimental study that was carried out in part 1 [1]<span "="">. The experimental study in part 1 focused on evaluation of the effectiveness of Montmorillonite clay, calcium carbonate, and silicon dioxide nanoparticles for enhancing the performances of epoxy adhesives used in re-assembly of archaeological </span>massive limestones. Based on the obtained results in part 1, the choice fell on epoxy-clay nanocomposites as the best re-assembly adhesive material reinforced with Stainless Steel to conduct the applied study project. The current applied study that <span "="">represents a big project was carried out on 3 archaeological pharaonic massive limestones discovered separately in Ain Shams (Heliopolis) archaeological area in Egypt. The methodology included an accurate archaeological study, followed by analytical, and then the restoration and reassembly process. Firstly;in order to prove whether these artifacts are complementary to each other or not, then with a view to re-assembly and conserving these artifacts in the form of one stone block to be ready for museum display. Referred to the comprehensive archaeological and analytical study of the mentioned archeological stones, the results confirmed that, these stone pieces, in the original were one piece, therefore, it is possible to regrouping again to become one block complementary to each other, and this is what was done in this study.展开更多
Based on the eigenfunction expansion technique, the wave generation by a piston wave maker in a wave flume with a partially reflecting end-wall is studied. The corresponding velocity potential and wave elevation in th...Based on the eigenfunction expansion technique, the wave generation by a piston wave maker in a wave flume with a partially reflecting end-wall is studied. The corresponding velocity potential and wave elevation in the flume are obtained. The present analytical solution is verified by the numerical results obtained from a time-domain higher-order boundary element method in a closed flume. Numerical experiments are further carried out to study the difference between the partial/full reflection boundary and the transmission boundary and the effects of the reflection coefficient and the motion period of the wave maker on the wave height. Meanwhile, the natural frequency of the wave flume can be obtained from the analytical expression. The resonance occurs when the motion frequency is equal to the natural frequency. Even the partial reflection of the end-wall in the wave flume experiments has a great influence on the wave height, therefore, inaccurate measurements would be resulted in long-time simulations, especially when the wave frequency approaches the wave flume natural frequency. The present study can serve as a guidance for the physical experiment in wave flumes.展开更多
Analytic formulas for acoustic interference patterns in shallow water are derived by ray method. Which can be used to guide acoustic measurements with limited horizontal distances. Some necessary approximations are ta...Analytic formulas for acoustic interference patterns in shallow water are derived by ray method. Which can be used to guide acoustic measurements with limited horizontal distances. Some necessary approximations are taken for a concise expression. The analytic for- mulas represent the quantitative relationships between the interference-pattern and the signal frequency, bandwidth, depth of source and horizontal distance. Monofrequent signals, com- plicated signals and frequency-modulated signals are all studied. Several inferences are also deduced from the formulas. Both numerical simulations and experiment data are presented to prove that these formulas and their inferences can describe the critical characters of the acoustic interference pattern in the waveguide with a satisfying precision.展开更多
Fundamental features of aerodynamic interference and integration of airframes and air-breathing jet engines for high-speed flight vehicles are studied within the framework of supersonic small perturbation theory.Both ...Fundamental features of aerodynamic interference and integration of airframes and air-breathing jet engines for high-speed flight vehicles are studied within the framework of supersonic small perturbation theory.Both the influence of airframe components on air intakes performance and influence of intakes on vehicle external aerodynamics are under consideration.Analytical relations and specific examples show that significant favorable interference between airframes and air intakes can be realized by using preliminary compression of the flow in front of intakes at flight Mach numbers exceeding approximately 3.展开更多
文摘The Antarctic ozone hole which was discovered in the mid 1980s has caused much attention from the scientists and politicians throughout the world.For the formation of the Antarctic ozone hole, most scientists believe that the man-made chemical materials such as CFCs etc. are main cause. On the other hand, the electrochemistry-dynamics theory presented by Wei (Guang Ming Daily Dec. 11 ,1990) two years ago has also caused some attention.In the paper the data of ozone, solar activity meteorology over Antarctica have been used for statistical analytical studies. Our results present some new evidence to support Wei's theory. However the influence of the human activities can never be slighted.
文摘In this paper the analytical performance of the low-powered Ar microwave plasma torch atomic emission spectrometry(MPT-AES) was studied.The experimental results indicate that the analytical performance of low-powered ArMPT-AES is satisfactory.
文摘An explicit analytical solution is presented for unidirectionally coupled two Murali-Lakshmanan-Chua circuits exhibiting chaos synchronization in their dynamics. The transition of the system from an unsynchronized state to a state of complete synchronization under the influence of the coupling parameter is observed through phase portraits obtained from the analytical solutions of the circuit equations characterizing the system.
文摘This part of study represents the applied study;which is a continuation of the experimental study that was carried out in part 1 [1]<span "="">. The experimental study in part 1 focused on evaluation of the effectiveness of Montmorillonite clay, calcium carbonate, and silicon dioxide nanoparticles for enhancing the performances of epoxy adhesives used in re-assembly of archaeological </span>massive limestones. Based on the obtained results in part 1, the choice fell on epoxy-clay nanocomposites as the best re-assembly adhesive material reinforced with Stainless Steel to conduct the applied study project. The current applied study that <span "="">represents a big project was carried out on 3 archaeological pharaonic massive limestones discovered separately in Ain Shams (Heliopolis) archaeological area in Egypt. The methodology included an accurate archaeological study, followed by analytical, and then the restoration and reassembly process. Firstly;in order to prove whether these artifacts are complementary to each other or not, then with a view to re-assembly and conserving these artifacts in the form of one stone block to be ready for museum display. Referred to the comprehensive archaeological and analytical study of the mentioned archeological stones, the results confirmed that, these stone pieces, in the original were one piece, therefore, it is possible to regrouping again to become one block complementary to each other, and this is what was done in this study.
基金supported by the Open Fund of Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering (Grant No.2009491611)the National Natural Science Foundation of China(Grant Nos.50709005,10772040 and 50921001)the Major National Science and Technology Projects of China(Grant No.2008ZX05026-02)
文摘Based on the eigenfunction expansion technique, the wave generation by a piston wave maker in a wave flume with a partially reflecting end-wall is studied. The corresponding velocity potential and wave elevation in the flume are obtained. The present analytical solution is verified by the numerical results obtained from a time-domain higher-order boundary element method in a closed flume. Numerical experiments are further carried out to study the difference between the partial/full reflection boundary and the transmission boundary and the effects of the reflection coefficient and the motion period of the wave maker on the wave height. Meanwhile, the natural frequency of the wave flume can be obtained from the analytical expression. The resonance occurs when the motion frequency is equal to the natural frequency. Even the partial reflection of the end-wall in the wave flume experiments has a great influence on the wave height, therefore, inaccurate measurements would be resulted in long-time simulations, especially when the wave frequency approaches the wave flume natural frequency. The present study can serve as a guidance for the physical experiment in wave flumes.
文摘Analytic formulas for acoustic interference patterns in shallow water are derived by ray method. Which can be used to guide acoustic measurements with limited horizontal distances. Some necessary approximations are taken for a concise expression. The analytic for- mulas represent the quantitative relationships between the interference-pattern and the signal frequency, bandwidth, depth of source and horizontal distance. Monofrequent signals, com- plicated signals and frequency-modulated signals are all studied. Several inferences are also deduced from the formulas. Both numerical simulations and experiment data are presented to prove that these formulas and their inferences can describe the critical characters of the acoustic interference pattern in the waveguide with a satisfying precision.
文摘Fundamental features of aerodynamic interference and integration of airframes and air-breathing jet engines for high-speed flight vehicles are studied within the framework of supersonic small perturbation theory.Both the influence of airframe components on air intakes performance and influence of intakes on vehicle external aerodynamics are under consideration.Analytical relations and specific examples show that significant favorable interference between airframes and air intakes can be realized by using preliminary compression of the flow in front of intakes at flight Mach numbers exceeding approximately 3.