同位旋非对称核物质性质与扩展的BHF方法(Ⅰ)同位旋相关的扩展的BHF方法

通过引进基态关联和同位旋自由度的区分 ,推广了Brueckner Hartree Fock理论方法 ,并应用于同位旋非对称核物质 ,系统地研究了在整个同位旋自由度范围内核物质的状态方程和单粒子特性及其同位旋效应 .还研究了微观三体核力对同位旋非对称核物质性质及其同位旋效应的影响 ,定量讨论了三体力效应与相对论性平均场理论及Dirac Brueckner方法的联系 .主要给出了同位旋相关的Brueckner Hartree Fock方法的基本理论和计算公式

Au LX射线发射截面和Al、Ti、Ni表面可见、红外光谱测量

本实验工作是在中国原子能科学研究院的HI-13串列加速器国家实验室第二测量厅原子物理实验平台上完成。本工作采用能量为20-50MeV的高电荷态O5+离子去轰击Au, 测量了不同能量下Au的L1、Lα、Lβ、Lγ的X射线谱，计算了不同能量下各条X射线的产生截面，并与ECPSSR理论计算结果进行了比较。实验结果表明σ（Ll）/σ(Lα) 和σ（Lγ）/σ(Lα)与ECPSSR理论计算结果符合比较好，而对于σ（Lβ）/σ(Lα)，在较低能区实验值略高于理论值。在中国科学院近代物理研究所320kV高电荷态离子实验研究平台上测量了Xeq+ (q=17-29)入射Al、Ti和Ni等表面诱发的可见光和红外光。通过对靶原子光谱线的研究，实验发现，随着入射离子的电荷态增高，原子和离子的各种光谱线可得到有效地激发。低速高电荷态离子入射金属固体表面，靶原子的特征谱线的激发强度，与入射离子的电荷态q密切相关。qc的实验测量值和理论计算值符合的较好

利用惰性气体离子注入制备Au纳米颗粒/蓝宝石复合材料

在绝缘体衬底中金属纳米颗粒的制备，常采用金属离子直接注入的方法，这一方法存在的问题主要是，所形成的金属颗粒尺寸离散较大，使这类材料的应用受到了限制。惰性气体离子注入到某些材料中所形成的纳米气泡或空腔的尺寸分布较均一，且纳米空腔具有吸附金属离子的性质。在此基础上我们提出：利用惰性气体离子注入预先在材料中形成尺寸分散较小的纳米空腔埋层，然后在样品表面沉积Au膜，再尝试通过高温扩散或离子束附加辐照的方法制备Au纳米颗粒。实验结果表明，高温退火的方法未在样品内部形成Au颗粒，离子束附加辐照的方法在样品内形成了尺寸分散较小的Au纳米颗粒，这为制备尺寸分散小的金属纳米颗粒复合材料提供了借鉴和新方法。论文中用多种测试方法（PL、UV-VIS、RBS、SEM、TEM）分析讨论了Ar的注入剂量、热处理温度、样品表面取向等参量对制备Au纳米颗粒的影响，并利用M-G理论对所研究体系的光吸收性质进行了模拟计算和定性解释

Recent advances in the study of biomolecular interactions by capillary electrophoresis

Capillary electrophoresis (CE) has been abundantly used in the study of molecular interactions owing to such advantages as short analysis time, low sample size requirement, high separation efficiency, and flexible applications. The focus of this paper is to 2 review recent studies and advances (mainly from 1998 to now) in biomolecular interactions using CE. Five CE modes: zone migration CE, affinity CE, frontal analysis (FA), Hummel-Dreyer (HD) and vacancy peak (VP) are cited and compared. Quantitative aspects of the thermodynamics and kinetics of biomolecular interaction are reviewed. Several biomolecular binding systems, including protein-protein (polypeptide), protein-DNA (RNA), protein(polypeptide)-carbohydrate, protein-small molecule, DNA-small molecule, small molecule-small molecule, have been well characterized by CE. CE is shown to be a powerful tool for the determination of the binding parameters of various bioaffinity interactions.

NBPT与DMPP不同剂量组合对尿素氮转化的影响

采用室内模拟试验的方法,探讨了脲酶抑制剂N-丁基硫代磷酰三胺(NBPT)和硝化抑制剂3,4-二甲基吡唑磷酸盐(DMPP)的不同浓度组合对尿素氮转化的影响。结果表明,NBPT与DMPP不同浓度组合均不同程度的延缓了尿素的水解,使尿素N水解产物更加以NH4+-N形态保持在土壤中;延缓了硝化作用进程并减少了硝酸盐在土壤累积,在此基础上增加了土壤有效态N含量。综合不同浓度组合对尿素水解的抑制、土壤NH4+-N和NO3--N含量变化、硝化作用抑制效果、土壤有效态N水平等指标并结合成本考虑,NBPT和DMPP分别为0.1%和0.5%施氮量时为最适宜的组合。

Thermodynamic investigation of the azeotropic mixture composed of water and benzene

The molar heat capacity of the azeotropic mixture composed of water and benzene was measured by an adiabatic calorimeter in the temperature range from 80 to 320 K. The phase transitions took place in the temperature range from 265.409 to 275.165 K and 275.165 to 279.399 K. The phase transition temperatures were determined to be 272.945 and 278.339 K, which were corresponding to the solid-liquid phase transitions of water and benzene, respectively. The thermodynamic functions and the excess thermodynamic functions of the mixture relative to standard temperature 298.15 K were derived from the relationships of the thermodynamic functions and the function of the measured heat capacity with respect to temperature.

Kinetic study on the photo-catalytic degradation of pyridine in TiO2 suspension systems

It has been generally agreed that pyridine can be effectively mineralized in aerated TiO2 slurries using near-UV irradiation. The knowledge on the kinetics of the system possesses both practical and theoretical values. The present study, on the base of Langmuir-Hinshewood mechanism, illustrates a pseudo first-order kinetic model of the degradation with the limiting rate constant of 3.004 mg l(-1) min(-1) and equilibrium adsorption constant 2.763 x 10(-2) l mg(-1), respectively. The degradation efficiency in alkali is a little higher than that in acid with a minimum at about pH = 5, which is explained by the formation of acid-pyridine in acidic surrounding together with the amphoteric nature of the TiO2 surface. The promotion of H2O2 on the photo-degradation ties in its supplying proper amount of (OH)-O-. radicals for the inducement stage before surface redox reactions. (C) 2004 Elsevier B.V. All rights reserved.

沉积时间对磁控反应溅射制备TiO_2薄膜性能的影响

应用直流磁控反应溅射法,在玻璃基体上制备了具有光催化活性的TiO2薄膜。TiO2薄膜的厚度随沉积时间的增加而均匀增长。基体温度则在溅射的最初1h很快上升到110℃,溅射7h基体温度不超过130℃。溅射2h得到的是非晶态TiO2薄膜,而溅射3~7h制备的薄膜为锐钛矿型结构。非晶态和小晶粒TiO2薄膜的紫外-可见透射光谱谱带边沿与结晶较好的TiO2薄膜相比有明显的蓝移,薄膜的透射率随沉积时间的增加而下降。钛以四价钛的形式存在于TiO2薄膜中。TiO2薄膜的光催化活性随沉积时间和薄膜厚度的增加而有较大提高。

东北典型石油污灌区土壤中矿物油的时空分布特征

污水灌溉在解决缺水问题和补充土壤营养的同时,也带来了不容忽视的土壤污染问题。作为我国最大的石油污灌区,沈抚灌区由于长期污灌导致矿物油积累严重,土壤中矿物油浓度最高可达6 861.1 mg/kg,整个灌区矿物油污染具有以下特征:灌区表层土壤(0~20 cm)矿物油含量高于亚表层土壤(20~30 cm);不同土地利用方式污染程度存在差异,水田土壤高于旱地土壤;污灌年限越长,矿物油积累越严重,污灌41~50年的土壤中矿物油含量超过3 000 mg/kg;整个灌区矿物油含量呈现沿污水流向逐渐降低的趋势,高浓度区主要集中在离排放口较近的李石寨地区。

东北黑土有机碳、全氮空间分布特征

应用经典统计学方法,分析了东北黑土表层1100个样点的土壤有机碳(SOC)和全氮空间分布规律。结果表明土壤有机碳和全氮平均含量分别为19.25 g kg-1和1.89 g kg-1,从南到北随纬度增加而增加,土壤有机碳和全氮与纬度的相关系数分别为0.70和0.76;土壤有机碳、全氮与黏粒、砂粒在P<0.01水平上显著相关,其中与砂粒为显著负相关,而SOC与粉粒则在P<0.05水平下显著正相关;土壤全氮与粉粒没有相关性。