1121A型放大／甄别器与光谱链接口设计

１１２１Ａ型放大／甄别器与光谱链接口设计朱克荣（安徽大学现代实验与技术中心合肥２３００３９）龙长应，陈鹤平，赵华正（安徽大学物理系合肥２３００３９）ＴｈｅＩｎｔｅｒｆａｃｅＤｅｓｉｇｎｏｆＭｏｄｅｌ１１２１ＡＡｍｐｌｉｆｉｅｒ－Ｄｉｓｃｒｉｍｉｎａｔ...     

量子拍频系统的拉曼散射

量子拍频系统的拉曼散射曹卓良，朱克荣，赵华正（安徽大学物理系合肥２３００３９）ＲａｍａｎＳｃａｔｔｅｒｉｎｇＥｆｆｅｃｔｏｆＡＱｕａｎｔｕｍ－ｂｅａｔＡｔｏｍｉｃＳｙｓｔｅｍ￥ＣａｏＸｈｕｏｌｉａｎｇ；ＺｈｕＫｅｒｏｎｇａｎｄＺｈａｏＨｕａｚｈｅｎｇ...     

“绿漆古”铜镜表层结构成分分析

“绿漆古”铜镜表层结构成分分析左健，邢锦云，刘先明，毛振伟，许存义（中国科学技术大学结构成分分析开放实验室安徽合肥２３００２６）ＳｔｒｕｄｕｒｅａｎｄＥｌｅｍｅｎｔａｌＡｎａｌｙｓｉｓｏｎＴｈｅＳｕｒｆａｃｅｉｎＡｎｃｉｅｎｔＣｈｉｎｅｓｅＧｒｅｅｎ...     

Resonant Fluorescence of a Λ-type Degenerate Quantum-beat Three-level Atom

ＲｅｓｏｎａｎｔＦｌｕｏｒｅｓｃｅｎｃｅｏｆａΛｔｙｐｅＤｅｇｅｎｅｒａｔｅＱｕａｎｔｕｍｂｅａｔＴｈｒｅｌｅｖｅｌＡｔｏｍＣＡＯＺｈｕｏｌｉａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，ＡｎｈｕｉＵｎｉｖｅｒｓｉｔｙ，Ｈｅｆｅｉ２３００３９...     

第六届光谱分析学术讨论会和《光谱实验室》创刊10周年纪念会论文摘要

第六届光谱分析学术讨论会和《光谱实验室》创刊１０周年纪念会论文摘要Ｌａ（Ⅲ）－桑色素－二氧杂环乙烷－ＡＥＳ体系荧光法测定Ｌａ的研究赵祥大，胡乃良，朱俊发，徐霁昀，方惠敏（安徽大学化学系，合肥市，２３００３９）本文用荧光法研究了Ｌａ（Ⅲ）－桑色素－二氧...     

The Squeezing Operator and the Squeezed States of "Superspace

ＴｈｅＳｑｕｅｅｚｉｎｇＯｐｅｒａｔｏｒａｎｄｔｈｅＳｑｕｅｅｚｅｄＳｔａｔｅｓｏｆ＂Ｓｕｐｅｒｓｐａｃｅ＂￥ＳＵＮＣｈａｎｇｙｏｕ（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，ＨｅｉｈｅＴｅｃｈｅｒ＇ｓＣｏｌｌｅｇｅ，Ｈｅｉｈｅ１６４３００）ＭＡＡｉｑ...     

Analytic Subject Index to Volume BS,(1996 )

ＡｎａｌｙｔｉｃＳｕｂｊｅｃｔＩｎｄｅｘｔｏＶｏｌｕｍｅＢＳ，（１９９６）ＬＡＳＥＲＤＥＶＩＣＥＳＰＵｌｓｅｗｉｄｔｈｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｍｏｄｅ－ｌｏｃｋｅｄＴｉ：ｓａｐｐｈｉｒｅｌａｓｅｒｗｉｔｈｒｉｎｇｃａａｖｉｔｙＫｅｒｒ－ｌｅ...     

拉曼光活性(ROA)经典理论模型研究

拉曼光活性（ＲＯＡ）经典理论模型研究马树国吴国祯（清华大学物理系北京１０００８４）ＡＣｌａｓｉｃａｌＴｈｅｏｒｙｆｏｒｔｈｅＲａｍａｎＯｐｔｉｃａｌＡｃｔｉｖｉｔｙＭａＳｈｕｇｕｏ，ＷｕＧｕｏｚｈｅｎ（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，Ｔｓｉｎ...     

用同位素替代方法识别化合物ABPO_5(A=Ca,Sr,Ba)的内振动模

用同位素替代方法识别化合物ＡＢＰＯ５（Ａ＝Ｃａ，Ｓｒ，Ｂａ）的内振动模张昊施颖朱恪刘玉龙刘竟青赵铁男梁敬魁（中国科学院物理研究所北京１０００８０）ＶｉｂｒａｔｉｏｎａｌＳｐｅｃｔｒｏｓｃｏｐｙＳｔｕｄｉｅｓｏｆＩｎｔｅｒｎａｌＭｏｄｅｓｏｆＳｔｉｌｗ...     

拉曼光谱在医学上的应用（Ⅱ）

拉曼光谱在医学上的应用（Ⅱ）余国滔（北京大学生命科学学院北京１００８７１）ＢｉｏｍｅｄｉｃａｌＡｐｐｌｉｃａｔｉｏｎｓｏｆＲａｍａｎＳｐｅｃｔｒｏｓｃｏｐｙ（Ⅱ）ＹｕｅＫｗｏｋｔｏ（ＣｏｌｅｇｅｏｆＬｉｆｅＳｃｉｅｎｃｅｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓ...     

Potential Energy Surface of Cytosine and Tunneling Between Its Normal and Trans-imino Tautomer

The potential energy surface of H（13） proton in base cytosine of the DNA molecules is calculated at the Caussian 98 MP2/6-311C（d,p） level. Two potential wells are found. One corresponds to the normal cytosine, while the other corresponds to its trans-imino tautomer. The estimated tunneling probability of the H（13） proton from one well to another well shows that the life time of the proton staying in one of these wells is about 600 yrs. It is too long to let tautomers of cytosine be in thermodynamical equilibrium in a room temperature gas phase experiment.     

Potential Energy Surface of Cytosine and Tunneling Between Its Normal and Trans-imino Tautomer

The potential energy surface of H(13) proton in base cytosine of the DNA molecules is calculated at the Gaussian 98 MP2/6-311G(d,p) level. Two potential wells are found. One corresponds to the normal cytosine, while the other corresponds to its trans-imino tautomer. The estimated tunneling probability of the H(13) proton from one well to another well shows that the life time of the proton staying in one of these wells is about 600 yrs. It is too long to let tautomers of cytosine be in thermodynamical equilibrium in a room temperature gas phase experiment.     

Potential of metal–fullerene hybrids as strong nanocarriers for cytosine and guanine nucleobases: A detailed DFT study

In this article, the adsorption of cytosine and guanine molecules on the surface of Cr-doped C20 fullerene (C19Cr) and Ni-doped C20 fullerene (C19Ni) are studied using first-principles density functional theory (DFT) calculations. In order to thoroughly comprehend the influences of the molecules on the metal-fullerene complexes, the geometric parameters, the binding energies, transferred charges, the magnitude of dipole moments, thermochemical parameters, frontier molecular orbitals, and the global indices of activities are calculated. The results highlighted that the interactions of both cytosine and guanine molecules with metal-fullerene complexes are highly exothermic, suggesting that these molecules might be chemisorbed on their adsorbents. The C19Cr exhibits a better adsorption behavior toward the molecules compared to C19Ni, and cytosine has the higher binding energies with metal-fullerene complexes in comparison with guanine. Further analyses showed that the C19Cr experiences significant changes in its electronic properties upon adsorption of the cytosine molecule. However, the small variations in the electronic properties of C19Ni after complexation with guanine indicate that this complex is not sensitive to the guanine. Furthermore, the results of frontier molecular orbital reveal the strong (moderate) interactions between the C19Cr with the cytosine (guanine) molecule and moderate (weak) interactions between the C19Ni with the cytosine (guanine) molecule. Therefore, the C19Cr and C19Ni have moderate sensitivities to cytosine and guanine molecules. More excitingly, our findings divulge promising potential of the Cr-fullerene complex as a biochemical adsorbent for cytosine.     

3种核酸碱基(胞嘧啶、胸腺嘧啶、尿嘧啶)在银电极表面的吸附形态

通过表面增强拉曼散射研究了胞嘧啶、胸腺嘧啶和尿嘧啶在粗糙银电极表面上的吸附形态随电极电位的变化关系.大量的结构信息可从丰富的表面拉曼信号及其随电极电位相应的变化而获得.分析表明在电极电位负移过程中,胞嘧啶一直通过N3位垂直吸附于纳米银颗粒表面;而胸腺嘧啶分子和尿嘧啶分子在表面的吸附状态都随电位改变发生了变化,较正电位下...     

氢键质子的运动与胞嘧啶的变异几率

运用Gaussian98 MP2/6 311G(d， p)级的从头计算法计算了DNA分子中胞嘧啶碱基中H13质子的势能曲面。 发现有两个势阱: 其中一个对应正常的胞嘧啶， 而另一个则对应它的顺式亚胺式互变异构体。 质子在这两个势阱的束缚对热扰动是稳定的。 质子在势阱中像单摆一样绕着离它最近的氮原子摆动， 还可以远离氮原子与其它碱基形成氢键。 估算出的H13质子从一个势阱到另一个势阱的穿透几率表明质子呆在其中一个势阱中的寿命大约是6×102 a， 这使胞嘧啶和它的顺式亚胺式互变异构体在室温气相实验中远不能达到热平衡。 对这些结果的生物学意义作了讨论。 The potential energy surface of the H13 proton in base cytosine of theDNA molecules is calculated ab initio at the Gaussian98 MP2/6 311G(d， p) level. Two potential wells are found. One corre sponds to the normal cytosine， while the other corresponds to its imino tautomer. The bindings of the proton in these wells are stable enough against the thermo disturbance. The motions of the proton in these wells are oscillations around the nearest nitrogen atom like the pendulum， and may move far away from the nitrogen atom to form the hydrogen bond with other bases. The estimated tunneling probability of the H13 proton from one well to another well shows that the life time of the proton staying in one of these wells is about 6×102 a. It is too long to let tautomers of cytosine be in thermodynamical equilibrium in a room temperature gas phase experiment. The biological significance of these results is discussed.     

胞嘧啶、胸腺嘧啶在银胶体系中的傅里叶变换表面增强拉曼散射

胞嘧啶、胸腺嘧啶在银胶体系中的傅里叶变换表面增强拉曼散射胡凤霞，李勤，林书煌，张崇起（首都师范大学综合所，首都师范大学物理系，首都师范大学综合所，北京１０００３７）ＦｏｕｒｉｅｒＴｒａｎｓｆｏｒｍＳｕｒｆａｃｅ－ＥｎｈａｎｃｅｄＲａｍａｎＳｐｅｃｔｒ...     

Orientation of ordered structures of cytosine and cytidine -monophosphate adsorbed at Au(110)/liquid interfaces

It is demonstrated using reflection anisotropy spectroscopy that the adsorption of cytosine and cytidine -monophosphate at the Au(110) 1 x 2/electrolyte interface gives rise to ordered structures in which the base is oriented vertical to the surface and parallel to the [110] axis of the Au(110) plane.     

A cytosine-assisted carbon nanotubes junction: DFT studies

Since nucleobase-functionalized carbon nanotubes (CNTs) are important in the biological applications; the junction of a pair of CNTs through a bridging cytosine linkage is investigated based on density functional theory (DFT) calculations. In the exact model of study, the CNTs are bound to N₁ and C₅ atomic sites of cytosine to make possible the CNT–cytosine–CNT model. To systematically investigate the purpose, the models of original CNT, original cytosine, and primary models of cytosine–CNT in which one CNT is only bound to N₁ or C₅ atomic site of cytosine are also considered. The results of dipole moments and binding energies indicated that the CNT–cytosine–CNT model is the most stable one among all three possible models cytosine-functionalized CNT. The values of energy gaps indicated that the conducting properties of primary cytosine–CNT models are not changed referring to the original CNT but better conductivity could be observed for the CNT–cytosine–CNT model. The values of evaluated quadrupole coupling constants indicated that the electronic densities of nitrogen and oxygen atoms of cytosine detect notable affects during the functionalization processes by the zigzag CNTs and the oxygen atom of CNT–cytosine–CNT model could be proposed as the most proper interacting site of cytosine among other functionalized zigzag models and also the original cytosine. However, the changes of quadrupole coupling constants for the atoms of cytosine are almost negligible during the functionalization processes by the armchair CNTs.     

DNA碱基分子胞嘧啶和胸腺嘧啶的太赫兹光谱研究

利用太赫兹时域光谱技术获得了DNA碱基分子胞嘧啶和胸腺嘧啶在0.1―3.5 THz的特征吸收谱,发现胞嘧啶在2.53 THz的特征吸收细节信息。采用考虑了周期性边界条件的赝势平面波密度泛函方法对胞嘧啶分子晶体进行了结构优化和晶格动力学计算,模拟重现其太赫兹特征吸收光谱,并成功辨识了胞嘧啶在0.1―3.5 THz的所有特征吸收峰。研究结果表明,这些重要的生物分子在太赫兹频段表现出鲜明的光谱特性,胞嘧啶分子3.5 THz以下的吸收特性均来源于由分子间氢键支配的外振动模式。     

DNA strand breaks induced by concerted interaction of H radicals and low-energy electrons

We propose a mechanism of DNA single strand breaks induced by low-energy electrons. Density functional theory calculations have been performed on a neutral, hydrogenated, and/or negatively charged nucleotide of cytosine in the gas phase to identify barriers for the phosphate-sugar O–C bond cleavage. Attachment of the first excess electron induces intermolecular proton transfer to cytosine. The resulting neutral radical of hydrogenated cytosine binds another excess electron, and the excess charge is localized primarily on the C6 atom. A barrier encountered for proton transfer from the C2’ atom of the adjacent sugar unit to the C6 atom of cytosine is 3.6 and 5.0 kcal/mol, based on the MPW1K and B3LYP electronic energies corrected for zero-point vibrations, respectively. The proton transfer is followed by a barrier-free sugar-phosphate C–O bond cleavage. The proton transfer is impossible for the neutral nucleotide, as there is no local minimum for the product. In the case of anionic and hydrogenated nucleotides the same barrier determined at the B3LYP level is as large as 29.3 and 22.4 kcal/mol respectively. This illustrates that the consecutive hydrogenation and electron attachment make the nucleotide of cytosine susceptible to a strand break. The rate of the C–O bond cleavage in the anion of hydrogenated nucleotide of cytosine is estimated to be ca. 10¹⁰  s^-1. The proposed mechanism proceeds through bound anionic states, not through metastable states with finite lifetimes and discrete energy positions with respect to the neutral target. The results suggest that at least for DNA without hydration even very low-energy electrons may cleave the DNA backbone.