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121.
In the presence of spin and pseudospin (p-spin) symmetries, the approximate analytical bound states of the Dirac equation for scalar-vector-tensor Hulth6n potentials are obtained with any arbitrary spin-orbit coupling number using the Pekeris approximation. The Hulth6n tensor interaction is studied instead of the commonly used Coulomb or linear terms. The generalized parametric Nikiforov-Uvarov (NU) method is used to obtain energy eigenvalues and corresponding wave functions in their closed forms. It is shown that tensor interaction removes degeneracy between spin and p-spin doublets. Some numerical results are also given. 相似文献
122.
SONG Jian-Wen HAI Wen-Hua ZHONG Hong-Hua LUO Xiao-Bing 《理论物理通讯》2008,50(7):89-94
We investigate the exact solutions of one-dimensional (1D) time-independent Gross-Pitaevskii equation (GPE), which governs a Bose-Einstein condensate (BEC) in the magnetic waveguide with a square-Sech potential. Both the bound state and transmission state are found and the corresponding spatial configurations and transport properties of BEC are analyzed. It is shown that the well-known absolute transmission of the linear system can occur in the considered nonlinear system. 相似文献
123.
LI Ding 《中国物理C(英文版)》2008,32(2):160-164
We use Monte Carlo simulation to calculate the distributions of particles under adsorption force near planar and cylindrical surfaces,respectively.Both hard sphere interaction and repulsive Yukawa (screened coulomb) interaction are employed in our simulations.We study the influence of the inter-particle potentials.The difference between the MC simulation results and the analytical results of ideal gas model shows that the interaction between particles plays an important role in the density distribution under external fields.Moreover,the 2-dimensional constructions of particles close to the surface are studied and show relations of the interaction between particles.These results may indicate us how to improve the methods of building nanoparticle coatings and nano-scale patterns. 相似文献
124.
Nine low-lying electronic states of the AsP molecule, including Σ , Ⅱ, and △ symmetries with singlet, triplet, and quintet spin multiplicities, are studied using multi-reference configuration interaction method.The potential energy curves and the spectroscopic constants of these nine states are determined, and compared with the experimental observed data as well as other theoretical works available at present.Three quintet states are reported for the first time.Furthermore, the analytical potential energy functions of these states are fitted using Murrell-Sorbie function and least square fitting method. 相似文献
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Micron-sized silica gel particles were first surface-modified with coupling agent, γ-methacryloylpropyl trimethoxysilane (MPS), and the polymerizable double bonds were introduced onto the surfaces of silica gel particles, forming the modified particles MPS-SiO2. Subsequently, N,N-dimethylaminoethyl methacrylate (DMAEMA) was graft-polymerized on the surfaces of particles MPS-SiO2 in the manner of “grafting through”, resulting in the grafted particles PDMAEMA/SiO2. The grafted particles PDMAEMA/SiO2 were fully characterized with several means. The graft polymerization process of DMAEMA on particles MPS-SiO2 was studied in detail, and the optimal reaction conditions were determined. Thereafter, the adsorption properties of the grafted particles PDMAEMA/SiO2 for chromate anion and Cu2+ ion were preliminarily examined respectively. The experimental results indicate that the PDMAEMA grafting degree on PDMAEMA/SiO2 particles is limited because an enwinding polymer layer as a kinetic barrier on the surfaces of silica gel particles will be formed during the graft polymerization, and blocks the graft polymerization. In order to enhance PDMAEMA grafting degree, reaction time and temperature, and the used amount of initiator as well as the monomer concentration should be effectively controlled. The preliminary adsorption tests show that the grafted particles PDMAEMA/SiO2 are multi-functional. They possess very strong adsorption ability for CrO42− anion by right of strong electrostatic interaction, and have also adsorption action towards heavy metal ion by dint of complexing action. 相似文献
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目的:检测与分析实验动物血液RBC(RBC·O2,RBC·CO2),Hb(HbO2,HbCO2)和人体皮肤表面流动血液氧化·还原状态的成像与未成像可见光谱领域OD值特征,并为该技术对白癜风病表皮黑色素颗粒检测中的应用尊定基础。方法:利用不同光谱技术和invitro和invivo检测手段,统计分析血液不同状态下波长与位置的OD值信息。结果:invitro检测:动物血液Hb·O2和RBC·O2两者在可见领域均有367,414(Soret带)nm与541,576(Q带)nm的吸收峰位;血液Hb·CO2和RBC·CO2均有432(Soret带)与和553(Q带)nm的波长吸收峰位;血液RBC状态和Hb溶血状态波长吸收峰位无改变,只是在氧化与还原状态下有完全独立的吸收峰位,血液RBC状态和Hb溶血状态波长吸光度OD值之间,有显著性差异(p<0·01)。浓度为1·5×107cell·mL-1的RBC·O2和Hb·O2在576nm的吸收峰位吸光度(y)与红细胞浓度(x)做成两条回归曲线:既,Hb·O2(b1)^y=0·05 0·983x;RBC·O2(b2)y^=0·127 1·934x,两者之间差异有显著性(p<0·01)。invivo检测:在人手背皮肤表面ImSpector图像中RBC·O2状态在540,576nm,RBC·CO2状态在555和755nm处有吸收峰。选择(a:指甲,b:指,c:手背)三个点位分别进行波长检测,每点(n=10)545nm吸收峰的平均OD值,依次为0·83±0·001,0·73±0·001和0·62±0·001,其三处测定点的OD值之间有显著性差异(p<0·01)。结论:invitro检测的RBC与Hb两者波长吸收峰位不变,但吸光度OD值不同,认为RBC状态测定结果更接近于活体组织血管内原始状态。invivo检测对人体无任何侵袭与损伤,灵敏度高,测试时间短,并且同时获得被测样品的波长与位置信息画面等优势,有望表皮中黑素等有色颗粒的直接检测。 相似文献