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11.
Optics and Spectroscopy - Endometriosis is a benign gynecologic disorder. It is particularly common among young women and may make pregnancy difficult. In this study molecular level...  相似文献   
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In this paper, the nonlinear Volterra-Fredholm integro-differential equations are solved by using the homotopy analysis method (HAM). The approximation solution of this equation is calculated in the form of a series which its components are computed easily . The existence and uniqueness of the solution and the convergence of the proposed method are proved. A numerical example is studied to demonstrate the accuracy of the presented method.  相似文献   
14.
This work suggests a new analytical technique called the fractional homotopy perturbation method (FHPM) for solving fractional differential equations of any fractional order. This method is based on He’s homotopy perturbation method and the modified Riemann–Liouville derivative. The fractional differential equations are described in Jumarie’s sense. The results from introducing a modified Riemann–Liouville derivative in the cases studied show the high accuracy, simplicity and efficiency of the approach.  相似文献   
15.
A note on     
There is only one pair of non-real zeros of , and of , in the left half-plane. The Riemann Hypothesis implies that and have no zeros in the strip .

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16.
The structural,elastic,electronic,optical,and vibrational properties of the orthorhombic Pd2Ga compound are investigated using the norm-conserving pseudopotentials within the local density approximation in the frame of density functional theory.The calculated lattice parameters have been compared with the experimental values and found to be in good agreement with these results.The second-order elastic constants and the other relevant quantities,such as the Young’s modulus,shear modulus,Poisson’s ratio,anisotropy factor,sound velocity,and Debye temperature,have been calculated.It is shown that this compound is mechanically stable after analysing the calculated elastic constants.Furthermore,the real and imaginary parts of the dielectric function and the optical constants,such as the optical dielectric constant and the effective number of electrons per unit cell,are calculated and presented.The phonon dispersion curves are derived using the direct method.The present results demonstrate that this compound is dynamically stable.  相似文献   
17.
Joo C  Akkin T  Cense B  Park BH  de Boer JF 《Optics letters》2005,30(16):2131-2133
We describe a novel microscopy technique for quantitative phase-contrast imaging of a transparent specimen. The technique is based on depth-resolved phase information provided by common path spectral-domain optical coherence tomography and can measure minute phase variations caused by changes in refractive index and thickness inside the specimen. We demonstrate subnanometer level path-length sensitivity and present images obtained on reflection from a known phase object and human epithelial cheek cells.  相似文献   
18.
In this article, we discuss the analytic solution of the fully developed shock waves. The homotopy perturbation method is used to solve the shock wave equation, which describes the flow of gases. Unlike the various numerical techniques, which are usually valid for short period of time, the solution of the presented equation is analytic for 0 < t < ∞. The results presented converge very rapidly, indicating that the method is reliable and accurate.  相似文献   
19.
Two new vic-dioxime ligands and their complexes with Co+2, Ni+2, Cu+2, Cd+2, and Zn+2 ions were synthesized. Primer amines (3,4-methylenedioxaaniline and 4-methylbenzylamine) reacted with antichloroglyoxime to give 3,4-methylenedioxaphenylaminoglyoxime (H2L1) and N-(4-methylbenzyl)aminoglyoxime (H2L2) ligands. Structures of the ligands and their complexes are proposed based on elemental analyses, IR, UV-Vis, and 1H NMR spectra, magnetic susceptibility measurements, and thermogravimetric analyses (TGA). The article was submitted by the authors in English.  相似文献   
20.
Two new organic building units that contain dicarboxylate sites for their self‐assembly with paddlewheel [Cu2(CO2)4] units have been successfully developed to construct two isoreticular porous metal–organic frameworks (MOFs), ZJU‐35 and ZJU‐36, which have the same tbo topologies (Reticular Chemistry Structure Resource (RCSR) symbol) as HKUST‐1. Because the organic linkers in ZJU‐35 and ZJU‐36 are systematically enlarged, the pores in these two new porous MOFs vary from 10.8 Å in HKUST‐1 to 14.4 Å in ZJU‐35 and 16.5 Å in ZJU‐36, thus leading to their higher porosities with Brunauer–Emmett–Teller (BET) surface areas of 2899 and 4014 m2 g?1 for ZJU‐35 and ZJU‐36, respectively. High‐pressure gas‐sorption isotherms indicate that both ZJU‐35 and ZJU‐36 can take up large amounts of CH4 and CO2, and are among the few porous MOFs with the highest volumetric storage of CH4 under 60 bar and CO2 under 30 bar at room temperature. Their potential for high‐pressure swing adsorption (PSA) hydrogen purification was also preliminarily examined and compared with several reported MOFs, thus indicating the potential of ZJU‐35 and ZJU‐36 for this important application. Studies show that most of the highly porous MOFs that can volumetrically take up the greatest amount of CH4 under 60 bar and CO2 under 30 bar at room temperature are those self‐assembled from organic tetra‐ and hexacarboxylates that contain m‐benzenedicarboxylate units with the [Cu2(CO2)4] units, because this series of MOFs can have balanced porosities, suitable pores, and framework densities to optimize their volumetric gas storage. The realization of the two new organic building units for their construction of highly porous MOFs through their self‐assembly with [Cu2(CO2)4] units has provided great promise for the exploration of a large number of new tetra‐ and hexacarboxylate organic linkers based on these new organic building units in which different aromatic backbones can be readily incorporated into the frameworks to tune their porosities, pore structures, and framework densities, thus targeting some even better performing MOFs for very high gas storage and efficient gas separation under high pressure and at room temperature in the near future.  相似文献   
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