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Fe3O4 materials have many crystal forms, and the morphology of their nanomaterials is more diverse. Under the influence of nano-effects, they exhibit unique physical and chemical properties. The synthesized Fe3O4 materials with different morphologies have different properties. They are widely used in related fields such as electromagnetics, chemical engineering, catalysis, sensors, acoustics, medicine, environmental protection and so on. Choosing the appropriate contrast agent to display the anatomical characteristics of diseased and normal tissue is an important thing before using MRI (Magnetic Resonance Imaging) technology. At present, Gd-DTPA is a commonly used magnetic contrast agent in clinical practice, but Gd-DTPA has obvious shortcomings, such as short circulation time, non-specific distribution, and high price. In comparison, the superparamagnetic iron oxide nanocrystals have a high specific distribution in living tissues, mainly concentrated in reticular endothelial cells-rich tissues and organs, such as liver, spleen, lymph nodes and bone marrow. This study analyzed the imaging characteristics of 21 patients with unilateral benign sphenoid sinus disease who were confirmed by nasal endoscopic surgery and postoperative pathology. Among the 21 patients with unilateral benign sphenoid sinus lesions, 7 cases of them had cysts. Those with altered sphenoid sinus cavity expansion may be accompanied by thinning of bone resorption. MRI manifested as long T1 and long T2 irregular spherical signal shadows. 8 cases of them are fungal lesions. MRI showed mixed signals are in the sphenoid sinus, the flaky exudation showed a high signal, and the fungal nodule showed a low T2WI signal. In the 3 cases of cerebrospinal fluid rhinorrhea, MRI showed a line between the high-signal shadow of the cerebrospinal fluid and the high-signal liquid shadow in the sinuses. High signal and shadow are connected, and other tissues (brain tissue, nasal mucosa) show low signal. Fe3O4-based MRI technology can improve imaging quality and diagnostic efficiency.

Fe₃O₄ materials have many crystal forms, and the morphology of their nanomaterials is more diverse. Under the influence of nano-effects, they exhibit unique physical and chemical properties. The synthesized Fe₃O₄ materials with different morphologies have different properties. They are widely used in related fields such as electromagnetics, chemical engineering, catalysis, sensors, acoustics, medicine, environmental protection and so on. Choosing the appropriate contrast agent to display the anatomical characteristics of diseased and normal tissue is an important thing before using MRI (Magnetic Resonance Imaging) technology. At present, Gd-DTPA is a commonly used magnetic contrast agent in clinical practice, but Gd-DTPA has obvious shortcomings, such as short circulation time, non-specific distribution, and high price. In comparison, the superparamagnetic iron oxide nanocrystals have a high specific distribution in living tissues, mainly concentrated in reticular endothelial cells-rich tissues and organs, such as liver, spleen, lymph nodes and bone marrow. This study analyzed the imaging characteristics of 21 patients with unilateral benign sphenoid sinus disease who were confirmed by nasal endoscopic surgery and postoperative pathology. Among the 21 patients with unilateral benign sphenoid sinus lesions, 7 cases of them had cysts. Those with altered sphenoid sinus cavity expansion may be accompanied by thinning of bone resorption. MRI manifested as long

Because of the tensile strength decreasing of the friction stir welded wrought magnesium (Mg) alloy compared to the base material, the reasons for the failure of weld has been focused on. After the fracture in transverse tension, the crack went through the welded joint from the center of the weld to the transition zone between the thermal-mechanical affected zone and weld zone. In the present study, the microstructure characteristics and its effect on the facture in the triple junction region is investigated. Based on the metallography and the electron back-scattered diffraction (EBSD) technology, it was observed that a twin band extended from the triple junction region to the middle of weld. The profuse twinning in the twin band was considered to play an important role on the crack propagation from the stir zone edge to the crown zone.

To study the growth inhibition and cell cycle changes in nasopharyngeal carcinoma (CNE1) cells after transfection with p53 gene. A mixture of nano-liposomes and plasmid containing p53 was used for transfecting CNE1 cells. Cellular apoptosis was examined after transfection using the CCK-8 reagent method with flow cytometry. The results showed that a ratio of nanoliposome/p-ORF-GFP of 3.5:1 showed the highest transfection efficiency in CNE1 cells. The cells transfected with a mixture of composites in this proportion showed significant apoptosis of up to 50–70%. In addition, we observed that cell cycle changes-measured using flow cytometry-as well as cellular apoptosis were accelerated after administration of composites. The CCK-8 kit was used to determine the viability of nano-liposome-encapsulated p53 transfected cells. In vitro experiments showed that the combination significantly inhibited the growth of CNE1 cells with an inhibition rate of approximately 63.8%. Therefore, the nanocomposites have a significant effect on inhibiting the growth of CNE1 cells. Through the investigation of apoptosis and cell cycle changes in CNE1 cells we found that the nanoliposome-encapsulated p53 gene can inhibit growth in these cells, and might therefore serve as a novel treatment strategy for adjuvant treatment of nasopharyngeal carcinoma and ca also reduce incompatibility issues with radiotherapy and chemotherapy. This method can also provide technical and theoretical support for the development of novel drugs.

By direct numerical simulation of the time-dependent Gross-Pitaevskii equation using the split-step Fourier spectral method we study the double-humped localization of a cigar-shaped Bose-Einstein condensate (BEC) in a one-dimensional bichromatic quasi-periodic optical-lattice potential, as used in a recent experiment on the localization of a BEC [G. Roati et al., Nature 453, 895 (2008)]. Such states are spatially antisymmetric and are excited modes of Anderson localization. Where possible, we have compared the numerical results with a variational analysis. We also demonstrate the stability of the localized double-humped BEC states under small perturbation.

Coupled dark–bright vector solitons are considered in a two-component Bose–Einstein condensate, and their dynamics are investigated by the variational approach based on the renormalized integrals of motion. The stationary states and their atom population distribution are obtained, and it is found that the dark soliton has obvious robust features. The dynamic mechanism is demonstrated by performing a coordinate of a classical particle moving in an effective potential field, and the switching and self-trapping dynamics of the coupled dark–bright vector solitons are discussed by the evolution of the atom population transferring ratio.

The dynamics of three coupled Bose–Einstein condensate solitons are investigated by the variational approach in finite potentials, and the switching and self-trapping effects on the three Bose–Einstein condensate solitons are studied. The stability issue is discussed by performing a standard linear stability analysis for the stationary states, and the dynamic mechanism is demonstrated by performing a coordinate of a classical particle moving in an effective potential field. The critical behavior of the three Bose–Einstein condensate solitons is analyzed, and confirmed by the evolution of the atom population transferring ratio versus time.

The evolution characteristics of a magnetostatic envelope bright soliton in magnetic thin films with higher-order dispersion are investigated analytically by means of the variational approach. It is found that the envelope of the soliton is changed due to the effects of the higher-order dispersion; the evolution of the soliton does not depend on its phase; and a stationary soliton can be formed in an appropriate situation. It reveals the relation between the motion of the soliton and the initial input pulse area.

Three coupled Bose-Einstein condensates are investigated by the variational approach in finite potentials with potential deviation, and the effects of the potential deviation on dynamics of the three Bose-Einstein condensates are studied. The potential deviation leads to the shift of the stationary state, resets the stability condition, causes the population imbalance competition, and changes the switching and self-trapping effects on the Bose-Einstein condensates. The effect mechanism is demonstrated by performing a coordinate of classical particles moving in an effective potential field. The critical behaviors are analyzed, and are confirmed by evolution of the atom population imbalance ratio.

The statics characteristics of two coupled Bose-Einstein condensate (BEC) dark solitons trapped in an optical lattice are investigated with the variational approach. It is found that the interaction between a ‘kink’ and an ‘anti-kink’ with opposite phase gradients is effectively repulsive, and the optical lattice can be controllably used to produce a pair of static BEC dark solitons. Its effect depends on the initial location of the BEC dark solitons, the lattice amplitude and wave number.

Effects of the traps are investigated on the dynamics of two coupled Bose–Einstein condensates, and the atom population transfer between the two condensates is discussed. It is found that the traps and the initial condition determine the switching and self-trapping effects on the atom population imbalance. There are the critical potential amplitude and the critical potential width, by which the oscillation manner of the population transferring ratio can be analyzed as time changes.

Stationary states of two coupled Bose-Einstein condensates (BECs) in trap potentials with a localized impurity are obtained by the variational approach, and effects of the impurity on the stationary states and the characteristics of the two coupled BECs are discussed by performing a standard linear stability analysis. The switching and self-trapping of the two coupled BECs strictly depends on the impurity, and the critical impurity strength value are given for initial in-phase and out-of-phase cases. Finally, the atom population transferring ratio of the two coupled BECs is introduced, and the Josephson oscillations of the population transfer are discussed as time changes.

Made available in DSpace on 2022-04-29T07:16:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-06-03 National Natural Science Foundation of China We study the localization of a noninteracting and weakly interacting Bose-Einstein condensate (BEC) with spin-orbit coupling loaded in a quasiperiodic bichromatic optical lattice potential using the numerical solution and variational approximation of a binary mean-field Gross-Pitaevskii equation with two pseudospin components. We confirm the existence of the stationary localized states in the presence of the spin-orbit and Rabi couplings for an equal distribution of atoms in the two components. We find that the interaction between the spin-orbit and Rabi couplings favors the localization or delocalization of the BEC depending on the phase difference between the components. We also studied the oscillation dynamics of the localized states for an initial population imbalance between the two components. © 2014 American Physical Society. Department of Physics, Hubei Normal University, Huangshi 435002 Instituto de Física Teórica, Universidade Estadual Paulista, 01.140-070 São Paulo, São Paulo Instituto de Física Teórica, Universidade Estadual Paulista, 01.140-070 São Paulo, São Paulo National Natural Science Foundation of China: 11274104

Made available in DSpace on 2022-04-29T02:04:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-11-29 By numerical solution and variational approximation of the Gross-Pitaevskii equation, we studied the localization of a noninteracting and weakly interacting Bose-Einstein condensate in a weakly perturbed optical lattice in one and three dimensions. The perturbation achieved through a weak delocalizing expulsive or a linear potential as well as a weak localizing harmonic potential removes the periodicity of the optical lattice and leads to localization. We also studied some dynamics of the localized state confirming its stability. © 2011 American Physical Society. Department of Physics Hubei Normal University, Huangshi 435002 Instituto de Física Teórica Universidade Estadual Paulista, 01.140-070 São Paulo, São Paulo Instituto de Física Teórica Universidade Estadual Paulista, 01.140-070 São Paulo, São Paulo

Made available in DSpace on 2022-04-29T00:49:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-25 We study the localization of a cigar-shaped superfluid Bose-Fermi mixture in a quasiperiodic bichromatic optical lattice (OL) for interspecies attraction and intraspecies repulsion. The mixture is described by the Gross-Pitaevskii equation for the bosons, coupled to a hydrodynamic mean-field equation for fermions at unitarity. We confirm the existence of the symbiotic localized states in the Bose-Fermi mixture and Anderson localization of the Bose component in the interacting Bose-Fermi mixture on a bichromatic OL. The phase diagram in boson and fermion numbers showing the regions of the symbiotic and Anderson localization of the Bose component is presented. Finally, the stability of symbiotic and Anderson localized states is established under small perturbations. © 2011 American Physical Society. Instituto de Física Teórica UNESP - Universidade Estadual Paulista, 01.140-070, São Paulo, São Paulo Department of Physics Hubei Normal University, 435002 Huangshi Instituto de Física Teórica UNESP - Universidade Estadual Paulista, 01.140-070, São Paulo, São Paulo

Made available in DSpace on 2022-04-28T22:02:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-28 By direct numerical simulation and variational solution of the Gross-Pitaevskii equation, we studied the stationary and dynamic characteristics of a cigar-shaped, localized, collisionally inhomogeneous Bose-Einstein condensate trapped in a one-dimensional bichromatic quasiperiodic optical-lattice potential, as used in a recent experiment on the localization of a Bose-Einstein condensate. The effective potential characterizing the spatially modulated nonlinearity is obtained. It is found that the collisional inhomogeneity has influence not only on the central region but also on the tail of the Bose-Einstein condensate. The influence depends on the sign and value of the spatially modulated nonlinearity coefficient. We also demonstrate the stability of the stationary localized state by performing a standard linear stability analysis. Where possible, the numerical results are shown to be in good agreement with the variational results. © 2011 American Physical Society. Instituto de Física Teórica UNESP - Universidade Estadual Paulista, 01.140-070 São Paulo, São Paulo Department of Physics Hubei Normal University, Huangshi 435002 Instituto de Física Teórica UNESP - Universidade Estadual Paulista, 01.140-070 São Paulo, São Paulo

Made available in DSpace on 2022-04-28T21:21:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-26 By numerical and variational solutions of the Gross-Pitaevskii equation, we studied the localization of a noninteracting and weakly interacting Bose-Einstein condensate (BEC) in a disordered cold atom lattice and a speckle potential. In the case of a single BEC fragment, the variational analysis produced good results. For a weakly disordered potential, the localized BEC's are found to have an exponential tail as in the weak Anderson localization. We also investigated the expansion of a noninteracting BEC in these potentials. We find that the BEC will be locked in an appropriate localized state after an initial expansion and will execute breathing oscillation around a mean shape when a BEC at equilibrium in a harmonic trap is suddenly released into a disorder potential. © 2010 The American Physical Society. Instituto de Física Teórica UNESP - Universidade Estadual Paulista, 01.140-070 São Paulo, São Paulo Department of Physics Hubei Normal University, Huangshi 435002 Instituto de Física Teórica UNESP - Universidade Estadual Paulista, 01.140-070 São Paulo, São Paulo

Made available in DSpace on 2022-04-28T20:59:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-24 By direct numerical simulation of the time-dependent Gross-Pitaevskii equation using the split-step Fourier spectral method, we study different aspects of the localization of a cigar-shaped interacting binary (two-component) Bose-Einstein condensate (BEC) in a one-dimensional bichromatic quasiperiodic optical-lattice potential, as used in a recent experiment on the localization of a BEC. We consider two types of localized states: (i) when both localized components have a maximum of density at the origin x=0, and (ii) when the first component has a maximum of density and the second a minimum of density at x=0. In the noninteracting case, the density profiles are symmetric around x=0. We numerically study the breakdown of this symmetry due to interspecies and intraspecies interactions acting on the two components. Where possible, we have compared the numerical results with a time-dependent variational analysis. We also demonstrate the stability of the localized symmetry-broken BEC states under small perturbation. © 2010 The American Physical Society. Instituto de Física Teórica UNESP-Universidade Estadual Paulista, 01.140-070 São Paulo Department of Physics Hubei Normal University, Huangshi 435002 Instituto de Física Teórica UNESP-Universidade Estadual Paulista, 01.140-070 São Paulo

The interaction of two coupled binary matter wave bright solitons is investigated by means of the variational approach in the presence of spatially varying nonlinearity. The effective potential characterizing the interaction between the two solitons is obtained. It is shown that the effective potential is composed of three parts, related to the spatially modulated nonlinearity, the external trapping potential and the interaction of the two coupled solitons. The spatially modulated nonlinearity induces a pseudo-potential and the solitons can be accelerated by the spatially modulated nonlinearity. The effect depends on the sign and value of the spatially modulated coefficient. The interaction of two coupled binary matter wave bright solitons is of short range, and may be attractive or repulsive depending on the sign of the interspecies interactions. Under the appropriate condition, the two coupled solitons can evolve stably and do not coalesce. The neighbouring binary Bose–Einstein condensates are also available as media to create symbiotic bright solitons. The validity of the theoretical predictions is verified by the numerical integration of the coupled Gross–Pitaevskii equations.

The evolution characteristics of a matter-wave bright soliton are investigated by means of the variational approach in the presence of spatially varying nonlinearity. It is found that the atom density envelope of the soliton is changed as a result of the spatial variation of the s-wave scattering length. The stable soliton can exist in appropriate initial conditions. The movement of the soliton depends on the sign and value of the coefficient of spatially modulated nonlinearity. These theoretical predictions are confirmed by the full numerical simulations of the one-dimensional Gross-Pitaevskii equation.

The characteristics of two coupled Bose-Einstein Condensate (BEC) bright solitons trapped in an optical lattice are investigated with the variational approach and direct numerical simulations of the Gross-Pitaevskii equation. It is found that the optical lattice can be controllably used to capture and drag the coupled BEC solitons. Its effect depends on the initial location of the BEC solitons, the lattice amplitude and wave-number, and the amplitude of the coupled BEC solitons. The effective interaction between the two coupled solitons is the attractive effect.

By use of the Kubelka-Munk theory, the Mie theory and the independent scattering approximation, we obtain the explicit expression of the emittance of an infrared coating attached to a radar absorber with a high emittance, in the 3~5microm window. Taking aluminum particles with spherical shape as the pigments within the coating, we give the dependence of the coating emittance with respect to the particle radius, the thickness of the coating. At a volume fraction of 0.05, we propose the optimum particle radius range of the pigment particles is around 0.35~0.6microm. When the thickness of the coating exceeds 300microm, the decrease of emittance at 4microm wavelength becomes negligible. Too much thickness of IR layer wouldn't contribute to the decrease of emittance. We study the influence of the infrared coating on the performance of the radar absorber, and believe that not too much thick infrared coating consisting of spherical Al particles wouldn't result in a remarkable deterioration of the absorbing ability of the radar absorber.