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101.
Linear and nonlinear elliptic complex partial differential equations of higher‐order are considered under Schwarz conditions in the upper‐half plane. Firstly, using the integral representations for the solutions of the inhomogeneous polyanalytic equation with Schwarz conditions, a class of integral operators is introduced together with some of their properties. Then, these operators are used to transform the problem for linear equations into singular integral equations. In the case of nonlinear equations such a transformation yields a system of integro‐differential equations. Existence of the solutions of the relevant boundary value problems for linear and nonlinear equations are discussed via Fredholm theory and fixed point theorems, respectively. 相似文献
102.
K. Ünlü C. Rios-Martinez B. W. Wehring 《Journal of Radioanalytical and Nuclear Chemistry》1995,193(1):145-154
A Prompt Gamma Activation Analysis (PGAA) facility is being developed at The University of Texas at Austin (UT). The UT-PGAA facility will utilize a focused cold-neutron beam from the Texas Cold Neutron Source (TCNS). the TCNS consists of a cold source cryostat and a curved neutron guide. the use of a guided focused cold-neutron beam will provide a high capture reaction rate and low background. The UT-PGAA facility will be used in the nondestructive determination of B, Cd, Gd and S in biological and environmental samples. 相似文献
103.
Correlation between radon exhalation and radium content in granite samples used as construction material in Saudi Arabia 总被引:1,自引:0,他引:1
Measurements of radon exhalation for a total of 205 selected samples of construction materials used in Saudi Arabia were carried out using an active radon gas analyzer with an emanation container. It was found that granite samples were the main source of radon exhalation. The radon exhalation rates per unit area from these granite samples varied from below the minimum detection limit up to with an average of 1.5 . The radium contents of 27 granite samples were measured using an HPGe-based γ spectroscopy setup. The 226Ra content of the granites varied from below the minimum detection limit up to , with an average of . The linear correlation coefficient between exhaled radon and radium content was found to be 0.90. 相似文献
104.
Nuri Ünal 《Foundations of Physics》1997,27(5):747-758
Barut's classicalzitterbewegung model includes the internal dynamical variables and the quantization of this system gives a general transition amplitude
between the different space-time points and internal coordinates and momentum. It includes the transition amplitude between
the half integer and integer spin eigenvalues. Spin eigenfunctions lead to all sets of relativistic wave equations, as well
as the Dirac equation. 相似文献
105.
Aybüke A. İsbir Turan Zafer Üstündağ Ali Osman Solak Emine Kılıç Ayça Avseven 《Electroanalysis》2008,20(15):1665-1670
This work describes the characterization of the grafted 2‐benzo[c]cinnoline (2BCC) molecules at a glassy carbon (GC) electrode surface by voltammetry and spectroscopy. Attachment of the molecule to the carbon substrate was achieved by the electrochemical reduction of 2‐benzo[c]cinnoline diazonium salt (2BCC‐DAS). GC electrode modification was carried out in aprotic solution with 2BCC diazonium salt. Dopamine (DA) and ascorbic acid (AA) were used to prove the surface modification to see the blockage of the electron transfer. The presence of 2BCC at the GC electrode surface was characterized by cyclic voltammetry and Raman spectroscopy. Raman spectroscopy was used to monitor molecular bound properties of the adsorbates at the 2BCC‐GC surface and confirm the attachment of 2BCC molecules onto the GC surface. The thickness of the 2BCC film on GC was also investigated by ellipsometric measurement. 相似文献
106.
107.
Partial capture rates in the reaction μ? + 12C → νμ + 12B are calculated using the generalized Helm model. The results are in good agreement with the recent experiment data. 相似文献
108.
109.
Hans-JÜrgen Glaeske 《Archiv der Mathematik》1966,17(5):438-442
Ohne Zusammenfassung 相似文献
110.
本文研究了水溶液中镉试剂1B对巯基乙酸稳定下CdTe量子点(CdTe QD)荧光和紫外吸收光谱的影响,文中分别考察了表面活性剂、缓冲介质、镉试剂2B用量、pH以及温度的影响。结果表明:镉试剂1B作用于CdTe QD后产生新的可见光谱吸收峰,并对CdTe QD的荧光有猝灭作用,同时借它们之间的作用可实现镉试剂1B对CdTe QD的包覆,表观平衡常数为1.095×106mol·L-1,表面覆盖率达45%。热力学结果显示,镉试剂1B与CdTe QD的作用是一个自发的、熵驱动的过程,其作用力主要表现为静电作用。 相似文献