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141.
The ground state properties of the spherical nucleus ^40Ca have been investigated by using constrained spherical Hartree Fock (CSHF) approximation at equilibrium and under high radial compression in a six major shells. The effective baryon-baryon interaction that includes the △(1236) resonance freedom degrees to calculate nuclear properties is used. The nucleon-nucleon (N-N) interaction is based on Reid soft core (RSC) potential. The results of calculations show that much of increase in the nuclear energy generated under compression is used to create the massive △ particles. The number of △ 's can be increased to about 2.1% of constituents of nucleus when nuclear density reaches about 1.34 times of normal density. The single particle energy levels are calculated and their behavior under compression is also examined. △ good agreement has been found between current calculations and phenomenological shell model for low lying single-particle spectra. The gap between shells is very clear and L-S coupling become stronger as increasing the static load on the nucleus. The results show a considerable reduction in compressibility when freedom degrees of △'s are taken into account. It has been found that the total nuclear radial density becomes denser in the interior and less dense in the exterior region of nucleus. The surface of nucleus becomes more and more responsive to compression than outer region. 相似文献
142.
Lai-Jiu Lin Qamrul Hasan Ansari 《Nonlinear Analysis: Theory, Methods & Applications》2010,72(3-4):1210-1220
In this paper, we introduce a system of quasi-variational relations (in short, SQVR) and present several examples which show that it is a very general and unified model of several problems. We establish the existence of solutions of SQVP, in general, and several other problems, in particular. As an application of our results, we derive maximal element theorems and a collectively fixed point theorem for a family of multivalued maps. As further applications, we study Ky Fan type inequality / inclusion problem for vector valued bifunctions which includes constrained Nash equilibrium problem as a special case. We also present a common fixed point theorem for a family of multivalued maps. The results of this paper improve and generalize several known results on (system of) quasi-equilibrium problems, (system of) quasi-variational inclusions, constrained Nash equilibrium problem, collectively fixed point theorem and KKM type theorems for a family of multivalued maps. Our results also contain several results which appeared in recent literature. 相似文献
143.
144.
Analysis of crossing fibers is a challenging topic in recent diffusion-weighted imaging (DWI). Resolving crossing fibers is expected to bring major changes to present tractography results based on the standard tensor model. Model free approaches, like Q-ball or diffusion spectrum imaging, as well as multi-tensor models are used to unfold the different diffusion directions mixed in a voxel of DWI data. Due to its seeming simplicity, the two-tensor model (TTM) is applied frequently to provide two positive-definite tensors and the relative population fraction modeling two crossing fiber branches. However, problems with uniqueness and noise instability are apparent. To stabilize the fit, several of the 13 physical parameters are fixed ad hoc, before fitting the model to the data. Our analysis of the TTM aims at fitting procedures where ad hoc parameters are avoided. Revealing sources of instability, we show that the model's inherent ambiguity can be reduced to one scalar parameter which only influences the fraction and the eigenvalues of the TTM, whereas the diffusion directions are not affected. Based on this, two fitting strategies are proposed: the parsimonious strategy detects the main diffusion directions without extra parameter fixation, to determine the eigenvalues and the population fraction an empirically motivated condition must be added. The expensive strategy determines all 13 physical parameters of the TTM by a fit to DWIs alone; no additional assumption is necessary. Ill-posedness of the model in case of noisy data is cured by denoising of the data and by L-curve regularization combined with global minimization performing a least-squares fit of the full model. By model simulations and real data applications, we demonstrate the feasibility of our fitting strategies and achieve convincing results. Using clinically affordable diffusion acquisition paradigms (encoding numbers: 21, 2*15, 2*21) and b values (b = 500–1500 s/mm2), this methodology can place the TTM parameters involved in crossing fibers on a more empirical basis than fitting procedures with technical assumptions. 相似文献
145.
We report a study of the 4 A 2g →2 T 1g absorption band of Mn4+ in Cs2SiF6. The band shows several lines or groups of lines associated with transitions from the 4 A 2g ground state to the spin-orbit components (2 T 1g )Γ8 and (2 T 1g )Γ6 coupled to the three odd-parity vibrations v 6(t 2u ), v 4(t 1u ) and v 3(t 1u ). The absorptions associated with the (2 T 1g )Γ8 electronic state have structure whereas those associated with the (2 T 1g )Γ6 do not. It is shown that the structure is a consequence of splitting of the Γ8 × v vibronic multiplets by electron-vibration interaction. The intensity of the 4 A 2g →(2 T 1g )Γ i + vj vibronic transitions are expressed in terms of a small number of parameters; two parameters for v(t 1u ) modes and three for v(t 2u ) modes. Plausible but not good fits to the low temperature Zeeman data and vibronic splitting patterns are obtained. The excitation spectrum of the Cs2SiF6 : Mn4+ in the region of the 4 A 2g →2 Eg and 4 A 2g →2 T 1g is recorded using a c.w. dye laser. This reveals numerous weaker lines involving combinational modes and even-parity modes v5 (t 2g ), v 2(eg ) and v 1(a 1g ). Several interesting electron-vibrational effects are observed. These are illustrated and discussed qualitatively. 相似文献
146.
Qamrul Hasan Ansari Martin Brokate 《Numerical Functional Analysis & Optimization》2013,34(9-10):949-959
In this paper, we study an iterative method, which includes the Ka?anov method as a particular case, for solving nonlinear variational inequalities of the second kind. A convergence result is also proved under suitable assumptions. We apply our iterative method to solve an elastoplasticity problem. 相似文献
147.
Some properties of pseudoinvex functions, defined by means of limiting subdifferential, are obtained. Furthermore, the equivalence between vector variational-like inequalities involving limiting subdifferential and vector optimization problems are studied under pseudoinvexity condition. 相似文献
148.
Michael Pigula Huang‐Chiao Huang Srivalleesha Mallidi Sriram Anbil Joyce Liu Zhiming Mai Tayyaba Hasan 《Photochemistry and photobiology》2019,95(1):378-386
Longitudinal monitoring of tumor size in vivo can provide important biological information about disease progression and treatment efficacy that is not captured by other modes of quantification. Ultrasound enables high‐throughput evaluation of orthotopic mouse models via fast acquisition of three‐dimensional tumor images and calculation of volume with a reasonable degree of accuracy. Herein, we compare orthotopic pancreatic tumor volume measurements determined by ultrasound with volume measured by calipers and tumor weight, and found strong correlations between the three modalities over a large range of tumor sizes, suggesting ultrasound can accurately quantify tumor volumes in this model. Furthermore, we demonstrate the unique ability of longitudinal treatment monitoring to reveal a tumor size‐dependent response to Benzoporphyrin Derivative photodynamic therapy (BPD‐PDT) and irinotecan. Small tumors (5–35 mm3) were found to respond well to a single round of PDT, while large tumors (35–65 mm3) showed no response to the same treatment. These results highlight the role that tumor size can play in preclinical interpretation of treatment response and more generally suggest that careful evaluation of subtle biological features such as this must be carefully considered in order to grant a more comprehensive understanding of disease biology in vivo. 相似文献
149.
Meghdad Pirsaheb Hiva Hosseini Hasan Mohamadi Sorkali Negar Noori 《International journal of environmental analytical chemistry》2019,99(2):112-123
In the present study, a new method for extraction and preconcentration of amoxicillin and ceftriaxone was used in hospitalised sewage samples, called vortex-assisted liquid-phase microextraction based on the solidification of deep eutectic solvent. Samples were analysed by high-performance liquid chromatography–ultraviolet detection after preparation and extraction. In this method, the new deep eutectic solvent is used as the extraction solvent, which is obtained from the combination of 1-decyl-3-methylimidazolium chloride and n-butanoic acid. The important advantages of this novel extraction solvent include material stability, low density and good freezing point near room temperature. Under the optimum conditions, enrichment factors are in the range of 164–172. Repeatability and reproducibility of the method based on seven replicate measurements of 50.0 µg L?1 of the target analytes in analysed samples were in the range of 2.1–3.5% and 3.8–5.2%, respectively. The limit of detections and linearity are in the range of 0.005–0.10 and 3–600 µg L?1, respectively. The method was successfully applied for the determination of amoxicillin and ceftriaxone in the real sewage samples. The relative recoveries of sewage samples spiked with amoxicillin and ceftriaxone are 91–107%. 相似文献
150.
Isahak Wan Nor Roslam Wan Hasan Siti Zubaidah Ramli Zatil Amali Che Ba-Abbad Muneer M. Yarmo Mohd Ambar 《Research on Chemical Intermediates》2019,45(3):951-953
Research on Chemical Intermediates - 相似文献