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1.
采用相对论多组态自洽场方法,计算了Cr^22+离子的精细结构能级,能级宽度,激发态寿命和光谱跃迁参数。计算中考虑了核的有限体积效应,Breit修正,QCD修正和轨道极化效应。所得结果与文献的实验值和计算值进行了比较。  相似文献   

2.
以相对论修正哈密顿(包括质量修正、单体和双体达尔文修正、自旋-自旋接触相互作用)的张量形式为基础,借助不可约张量理论导出了类氩体系基态能量的相对论修正的解析表达式.在斯莱特表象中完成了所有的角向积分和自旋求和计算,能量的相对论修正式用径向矩阵元的线性组合来表示.对类氩体系基态能量的相对论修正值进行了具体计算,修正后基态能量与实验值的相对误差小于0.0459%.  相似文献   

3.
本文通过F1uent模拟得到了在不同进气参数情况下悬索桥主缆的水分蒸发量和传质系数,通过与实验值的比对和修正得到了主缆传湿的半经验公式,验证主缆计算值和实验值之间的误差表明半经验公式具有较好的可靠性,运用半经验公式对气-液接触面积进行修正,通过对某大桥的计算结果表明,计算值与实际值误差较小,能够满足工程计算需要。  相似文献   

4.
本文以Watts提出的求解代数方程组的附加修正值法为基础,在油藏压力数值计算中,提出了一种加快油藏压力计算迭代收敛速度的分块修正技术.在计算过程中,将原来的整个计算区块一个修正值,改变成根据边界以及各计算区块孔隙度的不同,对不同的计算区域分块修正.通过计算表明,在同等计算条件下,分块修正技术较之单块修正明显加快了计算迭代收敛速度,最后本文对分块修正加快收敛速度的原因做了分析.  相似文献   

5.
基于相对论多组态自洽场方法 ,计算了CrⅠ至CrⅩⅩⅣ离子的基态能量和各价电离势 ,类氦Cr2 2 离子的电四极矩和磁偶极矩光谱跃迁数据。计算中考虑了核的有限体积效应、Berit修正、QED修正和轨道极化效应。计算结果与文献的实验和计算值进行了比较。  相似文献   

6.
基于相对论多组态自洽场方法,计算了CrⅠ至CrⅩⅩⅣ 离子的基态能量和各价电离势,类氦Cr22+离子的电四极矩和磁偶极矩光谱跃迁数据 。计算中考虑了核的有限体积效应、Berit修正、QED修正和轨道极化效应。计算结果与文献 的实验和计算值进行了比较。  相似文献   

7.
氦原子1sns组态能量及其相对论修正   总被引:2,自引:0,他引:2       下载免费PDF全文
利用Mathemtica语言开发了一套计算氦原子1sns组态能量的程序.提出了构造氦原子1sns组态波函数的新方法,利用Rayleigh.Ritz变分法对氦原子1sns(,n=2-5)组态的非相对论能量进行了计算,并计算了其相对论修正值(包括质量修正、单体达尔文修正、双体达尔文修正、自旋一自旋接触相互作用修正、轨道.轨道相互作用修正),计算结果与实验值相当接近.  相似文献   

8.
提出了构造碳原子1s22s22pns 3P态波函数的新方法,以Rayleigh-Ritz变分法为基础开发了一套计算碳原子1s22s22pns 3P态波函数和能量的Mathemtica程序,具体计算了碳原子1s22s22pns 3P(n=3-6)态的波函数和非相对论能量及其相对论修正值(包括质量修正、单体达尔文修正、双体达尔文修正、自旋-自旋接触相互作用修正),计算结果与实验值非常接近。  相似文献   

9.
利用干涉级次小数部分计算得到成像物镜相对焦距值,结合微小角度引起的相对位移值,实现微小角度测量的自校准.仿真计算了小数重合法的算法误差及温湿度误差,并实现了F-P间隔计算结果的修正,设计了可自校准的微小角度测量实验装置,通过测量实验得到了间隔修正前后成像物镜焦距值及微小角度测量结果.实验结果表明:在当前实验条件下,经修...  相似文献   

10.
在RC串联电路中τ值的修正   总被引:1,自引:0,他引:1  
对RC串联电路暂态实验中的时间常数测定计算进行了修正,较好地解决了测量值与计算值之间存在的误差问题。  相似文献   

11.
梁中翥  梁静秋  郑娜  贾晓鹏  李桂菊 《物理学报》2009,58(11):8039-8043
研究了金刚石光学特性与氮杂质及其含量的关系,从传统的金刚石氮含量标定方法出发,修正了金刚石氮含量的计算方法,并且用添加叠氮化钠的原料在六面顶压机上进行了高氮含量金刚石的制备研究.随着体系中叠氮化钠的添加,金刚石红外吸收谱在800—1400 cm-1范围的吸收强度相对于基线不断升高,这表明金刚石中存在的氮含量在随着叠氮化钠添加而升高,金刚石在单声子区域吸收强度大大增强.用含叠氮化钠的原料制备的金刚石呈现绿色、墨绿色甚至黑色,颜色的深浅依赖于叠氮化钠添加的多少.傅里叶红外光谱测试结果表明 关键词: 金刚石 光学材料 杂质 红外  相似文献   

12.
The substrate temperature(T_s)and N_2 partial pressure(P_(N2))dependent optical and electrical properties of sputtered InGaZnON thin films are studied.With the increased T_s and P_(N2),the thin film becomes more crystallized and nitrified.The Hall mobility,free carrier concentration(Ne),and electrical conductivity increase with the lowered interfacial potential barrier during crystal growing.The photoluminescence(PL)intensity decreases with the increased Ne.The band gap(Eg)narrows and the linear refractive index(n1)increases with the increasing concentration of N in the thin films.The Stokes shift between the PL peak and absorption edge decreases with Eg.The n1,dispersion energy,average oscillator wavelength,and oscillator length strength all increase with n1.The single oscillator energy decreases with n1.The nonlinear refractive index and third order optical susceptibility increase with n1.The Seebeck coefficient,electron effective mass,mean free path,scattering time,and plasma energy are all Ne dependent.  相似文献   

13.
星载高分辨率超光谱成像仪分光方式的选择   总被引:3,自引:0,他引:3  
从多个方面分析了棱镜和光栅色散分光的优缺点,分析结果表明棱镜更适于星载高分辨率超光谱成像仪的分光。在透过率方面,棱镜光谱仪透过率高达95.24%(VNIR),而光栅的衍射效率仅为60%~70%。在杂散光方面,棱镜光谱仪的杂散光可达10-4,而光栅的杂散光为10-2。在0.4 -2.5 范围,棱镜光谱仪相对光栅光谱仪有优越性。在色散线性方面,光栅光谱仪基本线性,棱镜光谱仪的短波非线性问题可通过复合棱镜进行补偿。可靠性方面,棱镜光谱仪较光栅光谱仪有优势;在光谱带宽和成本方面,棱镜光谱仪与光栅光谱仪基本接近。  相似文献   

14.
The experiment with 125I-Auger electrons, interacting with gaseous nitrogen with size equivalent to segment of DNA in mass per unit area scale, are described. The discrete ionization cluster-size distributions have been obtained. The shapes of which are definitely determined by the size of the interaction volumes. The volume sizes studied in the present work are comparable with a segment of DNA and of nucleosome. The experiments have been carried out with the set up, called Jet Counter, and are the first cluster-size distributions as yet measured for an Auger-electron emitter like 125I. The experimental results have been compared with those obtained by Monte Carlo simulation. The results for 125I have been compared with calculated cluster size distribution for 131I.  相似文献   

15.
简要介绍了JLab的一般情况、JLab高性能加速器CEBAF(Continue Electron Beam Accelerator Facility)和3个实验大厅的主要实验设备。着重介绍了CEBAF的连续束流与实验大厅的高密靶及高精度谱仪结合所得到的高精度实验结果,介绍了JLab实验室要解决的根本问题、相应的物理课题以及中国组正在参与数据分析和正在做的实验。最后简要介绍了CEBAF升级至12 GeV及其带来新的研究机会和新的物理课题,以及中国组与JLab的合作情况。The general situation of JLab is briefly introduced. The accelerator CEBAF with high quality and the equipments in the three Halls are described. The experimental results with high accuracies, which were obtained by using continue beam with high energy resolution, and high density target and high resolution spectrometers in the halls, are presented with two examples. The basic physics problems which JLab intends to solve, and the programs which JLab completed and is going to do, are stated. The programs which China group is cooperating with other groups are emphasized. The energy escalation for CEBAF will bring new opportunities for scientific researches.  相似文献   

16.
本文采用样品添加曲线法测定克山病非病区正常人及病区正常人潜,慢性克山病患者淋巴细胞中微量铜和锌,方法简便,快速,灵敏度高和精确度好,能有效的排除干扰,直线相关系数Cu:r=1.000,Zn:r=0.9992。相对标准偏差为2.3%-6.4%。回收率为93%-104%。结果表明4组人群Cu水平无差异。潜、慢克山病患者Zn/Cu比值增大。  相似文献   

17.
This work is concerned with reaction paths in the interaction of carbon defect-free nanostructures with different surface curvatures (graphene, tubulenes, and fullerene C60) with atomic and molecular oxygen. The interaction energies of atoms were calculated by the density functional theory method using the basis set of plane waves and the VASP package. The potential surface of reactions with molecular oxygen was studied by the nudged elastic band method. The energy parameters of the reaction (released energy and barrier) strongly depended on the curvature of carbon structure surfaces. The interaction of atomic oxygen in the ground state with the surface of carbon nanostructures is an exothermic reaction. The barrier to the reaction with molecular oxygen (0.5–2.5 eV) decreases as the curvature of nanostructure surfaces increases. The calculation results are in agreement with the experimental data and other ab initio calculations.  相似文献   

18.
The diameter of cylindrical openings is conventionally measured with the mechanical and contact method. In this paper, we propose a contactless optical approach to measure dimensions of inner profile by a disk beam probe. The measurement is carried out illuminating the inner cylindrical opening with a light sheet generated by the disk beam probe, acquiring the light-section image of the object with an image sensor through a widefield lens, then numerically extracting the diameter. During measurement, the probe is aligned inside the openings with high freedom, which causes the optical section to manifest a variety of ellipses besides a circle accordingly. The measurement method copes with extracting the diameter of openings from various ellipse optical sections. The high freedom of probe alignment allows optical diameter measurement to be flexible and simple. The dimensions of cylindrical openings of manufactured parts were practically measured with the disk beam probe, and the results were confirmed with those measured with the vernier caliper.  相似文献   

19.
孙伟峰  王暄 《物理学报》2013,62(18):186202-186202
通过分子动力学模拟对聚酰亚胺/铜纳米颗粒复合物的形态结构、 热力学性质、力学特性进行计算, 分析其随模拟温度和纳米颗粒尺寸的变化规律. 模拟结果表明, 聚酰亚胺/铜纳米颗粒复合物为各向同性的无定形态结构, 铜纳米颗粒与聚酰亚胺基体之间通过较强的范德华作用结合在一起使结构更加稳定, 铜纳米颗粒表面多个原子层呈现无定形状态, 在铜颗粒和聚酰亚胺基体之间形成界面层, 界面区域随颗粒尺寸和温度的增加分别减小和增加. 聚酰亚胺/铜纳米颗粒复合物的等容热容随着颗粒尺寸增大而明显增高, 随温度变化比聚酰亚胺体系更为缓慢, 在较低温度下较小颗粒尺寸复合物的热容比聚酰亚胺体系更低. 聚酰亚胺/铜纳米颗粒复合物的热压力系数随颗粒尺寸增加而显著增大, 比聚酰亚胺体系的热压力系数更小, 且随温度升高而减小的程度要小得多. 聚酰亚胺/铜纳米颗粒复合物的热力学性质表现出明显的尺度效应, 温度稳定性明显高于聚酰亚胺体系. 聚酰亚胺/铜纳米颗粒复合物的力学特性表现出各向同性材料的弹性常数张量, 具有比聚酰亚胺体系更低的杨氏模量和泊松比, 随温度升高分别减小和增大, 与聚酰亚胺体系随温度的变化趋势相反, 且杨氏模量的温度稳定性显著提高, 同时泊松比随纳米颗粒尺寸增大而减小, 具有明显的尺度效应. 加入铜纳米颗粒形成复合物可获得与聚酰亚胺体系显著不同的力学新特性. 关键词: 分子动力学模拟 聚合物纳米复合物 聚酰亚胺 纳米颗粒  相似文献   

20.
通过CO2激光器熔融不同直径的熔锥光纤以得到相应直径的石英玻璃微球,利用此微球和熔锥光纤,构造了球微腔耦合系统。实验中利用光腰直径为3.1μm的熔锥光纤与直径为143.1μm的石英玻璃微球进行耦合,通过最大分辨力为1pm的可调谐半导体激光器对该耦合系统进行光谱扫描,发现石英玻璃微球的吸收光谱中出现分立的结构共振峰。利用光学微球腔理论讨论了石英玻璃微球吸收光谱中的结构共振,并用米氏散射理论公式对一阶TE模共振峰的位置以及它们的间隔进行了计算,共振峰位置实验结果与理论结果的误差仅为0.03%,表明实验与计算结果相符。  相似文献   

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