二氧化碳非对称同位素16O12C17O 00011～00001跃迁带的高温谱线强度

利用本文计算所得配分函数和实验振动跃迁矩平方及Herman-Wallis因子系数,我们计算了二氧化碳同位素16O12C17O分子00011～00001跃迁在296 K和3000 K的线强度.结果显示,在296 K和3000 K时,计算所得线强度与HITRAN数据库提供的数据均符合较好.表明高温下的分子配分函数和线强度的计算是可靠的.从而进一步计算了二氧化碳同位素16O12C17O的000011～00001跃迁在4000 K和5000 K高温下的线强度及模拟光谱.     

The12 C+12 C →8 Be gs+16 O gs reaction atE cm=27 to 36 MeV

The¹² C+¹² C→⁸ Be _gs+¹⁶ O _gs reaction has been experimentally investigated at c.m. energies between 27 and 36 MeV. A resonance is present at 32.5 MeV,i.e. at the same energy of the resonance previously observed [1] in the¹² C(0 ₂ ⁺ )+¹² C(0 ₂ ⁺ ) exit channel, but its width is about three times narrower. Moreover the data indicate an enhancement of the cross section at a c.m. energy close to 29 MeV. These results are discussed and compared to the predictions of the Band Crossing Model obtained for different exit channels of the¹² C+¹² C reaction.     

￣16O ￣12C熔合截面粗共振现象的研究

应用核分子轨道理论（ＬＣＮＯ）和宇称相关势的折叠模型，研究了１６Ｏ＋１２Ｃ全熔合截面中所呈现的粗共振结构，该系统的全熔合截面和弹性散射激发函数及角分布的实验数据都得到了较好地解释。     

沸石17O固体核磁共振研究进展

沸石作为一类最重要的固体氧化物材料,是¹⁷O固体核磁共振最早研究对象之一. 近年来,随着核磁共振谱仪磁体场强的不断提高,以及新脉冲序列的发展,¹⁷O固体核磁共振被越来越多地应用于沸石的结构表征,在研究骨架氧结构以及测定Brønsted酸位的O-H键长等方面都提供了非常丰富的信息. 本文将介绍¹⁷O固体核磁共振的特点,回顾20年来它在沸石研究方面的发展并着重介绍近期这一方面的研究突破.      

The B 2Σ+–X 2Σ+ Transition of 12C17O+: The 2‐υ″ Progression

Abstract

Three new bands of the B ²Σ⁺–X ²Σ⁺ system of ¹²C¹⁷O⁺ have been investigated using conventional spectroscopic techniques. The spectra were observed in a graphite hollow‐cathode lamp by discharging molecular oxygen (enriched in about 45% of the ¹⁷O₂ isotope) under 1.0 Torr pressure. The rotational analysis of the 2–4, 2–5, and 2–6 bands was performed with the effective Hamiltonian of Brown (Brown et al., J. Mol. Spectrosc. 1979; 74: 294–318). Molecular constants were derived from a merge calculation, including both the current wavenumbers and the spectroscopic data published by the authors previously. The principal equilibrium constants for the ground state of ¹²C¹⁷O⁺ are ω_e=2185.9658(84), ω_e x _e = 14.7674(11), B _e=1.927001(38), α_e=1.8236(22)×10^?2, γ_e=?0.331(28)×10^?4, D _e=6.041(12)×10^?6, β_e=0.100(31)×10^?7 cm^?1, and the equilibrium constants for the excited state are σ_e=45876.499(15), ω_e=1712.201(12), ω_e x _e=27.3528(39), B _e=1.754109(35), α_e=2.8706(57)×10^?2, γ_e = ?1.15(19)×10^?4, D _e=7.491(20)×10^?6, β_e=2.13(12)×10^?7, γ_e = 2.0953(97)×10^?2, and α_γe=?9.46(59)×10^?4 cm^?1, respectively. Rydberg–Klein–Rees potential energy curves were constructed for the B ²Σ⁺ and X ²Σ⁺ states of this molecule, and Franck–Condon factors were calculated for the vibrational bands of the B–X system.     

沸石^17O固体核磁共振研究进展

沸石作为一类最重要的固体氧化物材料,是17O固体核磁共振最早研究对象之一.近年来,随着核磁共振谱仪磁体场强的不断提高,以及新脉冲序列的发展,17O固体核磁共振被越来越多地应用于沸石的结构表征,在研究骨架氧结构以及测定Brnsted酸位的O-H键长等方面都提供了非常丰富的信息.本文将介绍17O固体核磁共振的特点,回顾20年来它在沸石研究方面的发展并着重介绍近期这一方面的研究突破.     

Eu（C8H7O3）3·C12N2·H2O配合物的合成与表征

合成了新的Eu(C8H7O3)3·C12H8N2·H2O配合物.并经元素分析、摩尔电导、IR、UV、1H NMR等表征,初步确定配体3-甲氧基苯甲酸以桥式双齿形式和Eu(Ⅲ)配位.     

在独立α集团模型下对敲出反应16O(p,pα)12C和16O(α,2α)12C的研究

在独立α集团模型下,利用扭曲波冲量近似(DWIA),计算了实验室系下入射能量为101.5MeV的敲出反应16O(p,pα)12C和实验室系下入射能量分别为90MeV和140MeV的敲出反应16O(α,2α)12C.得到的反应截面和谱因子与实验数据基本符合,比用壳模型的结果有了一定的改进,表明独立α集团模型能较好地描述α集团敲出反应的机理.     

C6F12O对锂离子电池排出气体火焰的抑制效能研究

通过实验和数值模拟的方法研究了添加C_6F_(12)O对锂离子电池发生热失控后的排出气体/空气预混火焰的影响。在常温常压下,利用本生火焰装置测试了一定当量比范围的甲烷/空气和排出气/空气预混火焰在不同C_6F_(12)O添加量条件下的火焰速度。通过包含燃料燃烧和C_6F_(12)O热分解的动力学机理模型进行数值模拟并与实验测试的火焰速度进行比较,结果表明在C_6F_(12)O添加量较低的贫燃侧,层流火焰速度趋势具有良好的一致性。尽管燃料类型不同,C_6F_(12)O在化学当量以及富燃侧的抑制效能明显优于贫燃侧,并且相比于纯甲烷,C_6F_(12)O更适用于抑制排出气体/空气预混火焰。     

Die Spektren der Neutronen aus den Reaktionen C12(γ,n)C11 und O16(γ,n)O15

The (γ, n)-reactions on carbon and oxygen were studied using the 30,5 MeV brems-strahlung beam of the Heidelberg betatron. The photoneutrons were detected via the recoil protons in a stilbene scintillator. The pulse height spectrum of scintillations produced in the stilbene crystal by the recoil protons is analyzed to yield the incident neutron energy distribution. Theγ-ray and electron background was strongly reduced through pulse shape discrimination. To test the apparatus the spectrum of the neutrons from a Po-α-Be source was measured. The energy spectrum of the photo-neutrons from O¹⁶ shows clearly two peaks at excitation energies of 22,4 and 24,4 MeV also seen in the photo-proton spectra. The energy distribution of the neutrons from C¹² (γ, n) too contains indication of structure already known from the proton spectra from C¹² (γ, p). The derived cross sections of C¹² (γ, n ₀) and O¹⁶ (γ, n ₀) coincide as well in their shape as in their absolute magnitude with the corresponding (γ, p ₀)-cross sections. In both C¹² (γ, n) and O¹⁶ (γ, n)-reaction the neutrons seem to leave the final nucleus mainly in its ground state.     

Eu(C8H7O3)3·C12H8N2·H2O配合物的合成与表征

合成了新的Eu(C8H7O3)3·C12H8N2·H2O配合物.并经元素分析、摩尔电导、IR、UV、1H NMR等表征,初步确定配体3-甲氧基苯甲酸以桥式双齿形式和Eu(Ⅲ)配位.     

配合物La（C5O3H3）3·C12H8N2·H2O的合成和表征

本以α－呋喃甲酸（Ｃ５Ｏ３Ｈ４）和邻菲罗啉（Ｃ１２Ｈ８Ｎ２）为配体,在乙醇８溶剂中与硝酸镧反应,合成了与稀土离子Ｌａ（Ⅲ）的三元混配配合物。经元素分析确定其配合物的组成为Ｌａ（Ｃ５Ｏ３Ｈ３）·Ｃ１２Ｈ８Ｎ２·Ｈ２Ｏ,同时还通过了ＩＲ、＾１ＨＮＭＲ、ＵＶ、ＴＧ－ＤＴＡ等谱光的测试与分析,表征了配合物的组成结构和性质。ＩＲ、＾１ＨＮＭＲ和ＵＶ谱的分析结果表明配体羧酸是以脱质子的酸根形式与中心稀土离子     

CeMgAl11O19-SrAl12O19固溶体和CeMgAl11O19-SrMgAl10O17固溶体在稀土和碱土复合六角铝酸盐体系中的光谱学性质研究

本文研究CeMSAl11O19-SrAl12O19和CeMeAl11O19-SrMgAl10O17体系固溶体的发光性质。发现在CeMgAl11O19-SrAl12O19体系中,能形成完全的固溶体,随着SrAl12O19含量的增加,晶胞常数a线性地减小,c保持不变,Ce3+的Nephelauxetic效应和晶场强度减弱,Ce3+最低5d激发带边能量呈指数形式变化,Ce3+的发射能量线性地高移。在CeMgAl11O19-SrMgAl10O17体系中,不能形成完全的固溶体。固溶体终端组成大约为0.3CeMgAl11O19-0.1SrMgAl10O17。在这种固溶体中,晶胞常数α和c则随SrMgAl10O17含量分别线性地减小和增大。样品制备中添加H3BO3,引起固溶体晶僻特性改变,大大提高Ce3+的发光强度。但当H3BO3量超过0.4(摩尔比)时,硼将进入晶格,反而减弱Ce3+的发光。     

17C反应截面和去中子截面

利用日本理化学研究所的放射性束流线RIPS, 测量了能量为79A MeV的¹⁷C在¹²C反应靶上的反应截面, 并同时得到了¹⁷C的移去1个、2个及3个中子的截面; 分别利用有限力程Glauber模型和少体Glauber模型结合壳模型的谱因子分析了反应截面和移去1个中子截面, 研究了¹⁷C的密度分布、结构和价中子布居. 反应截面和中子移去截面是两个相互独立的量, 通过对两者的分析, 都可以得出¹⁷C由芯核¹⁶C和价中子组成, 并且价中子主要处于d_5/2轨道的结论. 总结了现有的碳同位素的反应截面和相互作用截面的工作.     

Measurement of 4He(12C,16 O)γ Reaction in Inverse Kinematics

A cross section measurement employing a direct ¹⁶O detection method for the reaction energies from E _cm = 2.4 to 0.7 MeV is planned at Kyushu University Tandem Laboratory. To perform this experiment and to obtain quantitative information about the cross section to within an error of 10%, we have developed several instruments, including a blow-in type windowless gas target and a ionization chamber. A target thickness of 24 × 3.9 Torr cm was achieved using the developed gas target. The particle identification was successfully performed by using the energy deposit in the ionization chamber. Experiments were performed at E _cm = 2.4 and 1.5 MeV using the developed instruments and the cross sections were obtained.     

The E1 capture amplitude in 12C(α,γ0) 16O

An excitation function of the ground-state γ₀-ray capture transition in ¹²C (α,γ)¹⁶O at θ_γ = 90^° was obtained in far geometry using six Ge detectors, where the study of the reaction was initiated in inverse kinematics involving a windowless gas target. The detectors observed predominantly the E1 capture amplitude. The data at E = 1.32 to 2.99 MeV lead to an extrapolated astrophysical S factor S _E1(E ₀) = 90±15 keV b at E ₀ = 0.3 MeV (for the case of constructive interference between the two lowest E1 sources), in good agreement with previous works. However, a novel Monte Carlo approach in the data extrapolation reveals systematic differences between the various data sets such that a combined analysis of all available data sets could produce a biased estimate of the S _E1(E ₀) value. As a consequence, the case of destructive interference between the two lowest E1 sources with S _E1(E ₀) = 8±3 keV b cannot be ruled out rigorously. Received: 6 June 2001 / Accepted: 26 July 2001     

Absolute Line Intensities in the 2ν3Band of16O12C32S

The strengths of 100 lines in the 2ν₃band of¹⁶O¹²C³²S have been measured at high resolution in the spectral range 4069–4118 cm⁻¹, using a tunable difference-frequency laser spectrometer. These intensities were obtained by fitting Voigt profiles to the measured shapes of the lines. The vibrational transition moment [(2.141 ± 0.020) × 10⁻²D] and the absolute intensity (16.19 ± 0.24 cm⁻²atm⁻¹at 296 K) of the 2ν₃band of¹⁶O¹²C³²S are determined from these linestrength measurements.     

First-principles study of two new boron nitride structures:C12-BN and O16-BN

Based on the first-principles method,we predict two new stable BN allotropes:C12-BN and O16-BN,which belong to cubic and orthorhombic crystal systems,respectively.It is confirmed that both the phases are thermally and dynamically stable.The results of molecular dynamics simulations suggest that both the BN phases are highly stable even at high temperatures of 1000 K.In the case of mechanical properties,C12-BN has a bulk modulus of 359 GPa and a hardness of 43.4 GPa,making it a novel superhard material with potential technological and industrial applications.Electronic band calculations reveal that both C12-BN and O16-BN are insulators with direct band gaps of 3.02 e V and 3.54 e V,respectively.The XRD spectra of C12-BN and O16-BN are also simulated to provide more information for possible experimental observation.Our findings enrich the BN allotrope family and are expected to stimulate further experimental interest.     

12C离子束的剂量学研究

研究了L-α-丙氨酸剂量计测量^12C离子辐射的剂量学特性，实验证明丙氨酸剂量计适用于^12C离子辐射的剂量学测量。另外，还研究了^12C离子照射人外周血诱发的染色体畸变（双着丝粒＋着丝粒环）的剂量效应，在0-8．0Gy范围内拟合的最佳回归方程为Y=0．858503D＋0．3615×10^-2D^2。Dosimetric characteristics of L-α-alanine dosemeter used for dosimetry of ^12C ion radiation have been studied. The experimental results indicate that the alanine dosemeter can be used to measure the ^12C ion radiation. In addition, dose effects of chromosome aberration dicentrics and cenric rings were studied after human peripheral blood being irradiated by ^12C ions; the best regression equation, Y = 0. 858 503D ＋ 0. 361 5 ×10^-2D^2, was obtained within 8.0 Gy.