乙酰二茂铁缩4—苯氨基硫脲与UO^2＋2,Hg^2＋,Ni^2＋,Zn^2＋,的…

乙酰二茂铁缩４－苯氨基硫脲（Ｃ１９Ｈ１９Ｎ３ＳＦｅ）与某些金属离子在无水乙醇中反应得到了希夫碱配合物Ｍ．Ｌ．Ｘ２．ｎＨ２Ｏ（Ｍ为ＵＯ＾２＋２，Ｈｇ＾２＋，Ｎｉ＾２＋，Ｚｎ＾２＋，Ｌ为Ｃ１９Ｈ１９Ｎ３ＳＦｅ；ＮＯ＾－３，Ｃｌ＾－，１／２ＳＯ＾２－４；ｎ＝０－６）并对配合物的组成及某些物理化学质进行了测试和表征。     

低能重离子及其碰撞产生的级联原子在生物材料中的直接作用范围

用Ｍｏｎｔｅ Ｃａｒｌｏ法模拟计算了３０ｋｅＶ和２００ｋｅＶ的Ｎ＾＋与１１０ｋｅＶ的Ｆｅ＾＋在模拟细胞中的射程分布和径迹结构，并将１１０ｋｅＶＦｅ＾＋模拟计算的结果与ＲＳＢ测量的结果相比较，发现计算与测量的结果吻合较好，离子的作用范围小于１μｍ。计算和实验的结果都说明能量相当低的重离子不大可能直接作用引起麦胚深层生物效应。     

注入低能重离子在模拟细胞中的能量沉积

用Ｍｏｎｔｅ Ｃａｒｌｏ法模拟计算了３０ｋｅＶ和２００ｋｅＶ的Ｎ＾＋与１１０ｋｅＶ的Ｆｅ＾＋模拟细胞中本身及级联离子非弹性散射产生的电子，分子振动的能量沉积；讨论了电子分子振动的总能量沉积的深度分布。     

注入30keVN^＋在模拟细胞中的溅射级联推进

用Ｍｏｎｔｅ Ｃａｒｌｏ方法模拟计算了３０ｋｅＶ的Ｎ＾＋在模拟细胞中溅射级联推进的影响。从计算结果看，在用１０＾１７个／ｃｍ＾２的３０ｋｅＶ的Ｎ＾＋注入生物材料时，溅射级联推进约为０３４μｍ，故得出溅射级推进作用不大可能造成植物诱变的结论。     

In^＋离子注入蓝宝石（α—Al2O3单晶）的表面改性研究

研究了〈０００１〉和〈１＾－２１０〉晶向蓝宝石（α－Ａｌ２Ｏ３单昌）在注入３６０ｋｅＶ、１×１０＾１６ｃｍ＾－２或１００ｋｅＶ、６×１０＾１６ｃｍ＾－１的Ｉｎ＾＋后产生的损伤、注入层的性能变化和退火行为。实验结果表明，退火过程中损伤的恢复和Ｉｎ的分布与退火气氛有关：在１００ｋｅＶ、６×１０＾１６ｃｍ＾－２的Ｉｎ＾＋注入时，注入层电阻率降低了１０个量级，大小为６．８×１０＾３Ω·ｃｍ，表面损伤层的显     

离子能量的快离子激光光谱学方法校刻

对离子能量进行校刻的快离子激光光谱学方法利用多普勒效应把离子能量与离子的共振激发联系起来，可应用于１ｅＶ－１００ＭｅＶ能区，在几十ｋｅＶ范围内，测量准确度优于２×１０＾－３，用这种方法校刻了＾１４４Ｎｄ＾＋的能量。     

C、Co及C+Co双注入对高速钢机械性能影响的研究

采用ＭＥＶＶＡ源离子注入机对高速工具钢进行了Ｃ,Ｃｏ及Ｃ＋Ｃｏ注入,并做了硬度,摩擦系数测量和磨损实验,Ｃ离子注入剂量３×１０＾１７ｃｍ＾－２能量６０ｋｅＶ,Ｃｏ离子注入剂量为２×１０＾１７,４×１０＾１７,６×１０＾１７ｃｎ＾－２能量１０２ｋｅＶ。结果表明,不同元素,不同剂量的离子注入均能有效地改善ＨＳＳ的硬度和摩擦磨损特性,从而极大延长ＨＳＳ的工作寿命,且随着注入剂量的增加,改善的效果有所增强     

高能离子注入对聚酰亚胺薄膜硬度的影响

报道了聚酰亚胺薄膜在高能（６５０ｋｅＶ－２ＭｅＶ）Ｂ＾＋、Ｃ＾＋和Ｃｕ＾＋离子注入后硬度的变化。对注入样品进行了显微硬度测量和ＸＰＳ及ＲＢＳ分析，观察了硬度与离子种类、能量及注入剂量的依赖关系。结果表明，离子注入之后薄膜样品的显微硬度值明显提高，注入离子在样品中的电子能量损失对聚合物材料改性起着关键作用。ＸＰＳ和ＲＢＳ分析显示，离子注入之后聚酰亚胺薄膜中Ｃ的含量增加，形成了以苯环结构为主的新的交联     

低能离子束辐照氨基酸结构变化的傅立叶变换红外光谱法研究

利用傅立叶变换红外光谱（ＦＴＩＲ）法研究了３０ｋｅＶ的Ｎ＾＋离子束辐照引起氨基酸结构的变化。结果表明：经相同剂量Ｎ＾＋离子束辐照后,天冬氨酸（Ａｓｐ）和苯丙氨酸（Ｐｈｅ）的基团有相似的变化规律,即羧酸根离子（ＣＯＯ＾－）的ｖＣ＝Ｏ伸缩振动（分别为１６４６ｃｍ＾－１和１６２６ｃｍ＾－１）均增强,ＮＨ３＾＋的谱峰（分别主要为１５１７ｃｍ＾－１和１５６０ｃｍ＾－１）强度均减弱。Ｐｈｅ较Ａｓｐ中的基因强度     

^13N—NH3.H2O的制备与质量控制

利用＾１６Ｏ（ｐ，α）＾１３Ｎ核反应，以小体积＾１６Ｏ－Ｈ２Ｏ靶生产＾１３Ｎ正电子核素，即用１６．５ＭｅＶ的质子束轰击＾１６Ｏ－Ｈ２Ｏ靶５－２０ｍｉｎ后，以戴氏合金（Ｄｅｖａｒｄ．ｓＡｌｌｏｙ）还原靶水，可得么１．９－６．７ＧＢｑ的＾１３Ｎ－ＮＨ３．Ｈ２Ｏ。产品经ＨＰＬＣ分析，放化纯度〉９５％，载体ＮＨ３的浓度〈１ｍｍｏｌ／Ｌ，比活度为４．４ＰＢｑ／ｍｏｌ，适用于临床ＰＥＴ的研究。     

Detection of Low Energy Heavy Particles with Silicon Barrier Detectors

The performance characteristics of silicon surface barrier detectors have been investigated for detecting H+, He+, N+, Ne+ and Ar+ in the energy interval 6-100 keV. For a cryogenically cooled, 50 mm2, 1325? depletion depth detector the resolution for protons was 1.65 keV (FWHM). The resolution decreased as the particle mass increased being 6.5 keV for 40 keV Ar+. All particles exhibit pulse height linearity throughout the energy range.     

Assessment of Neutron Cross Sections for Titanium with Neutron Spectrum in Titanium Pile

The measurement of angular neutron spectrum in a quasi-spherical pile of Ti was carried out by the linac time-of-flight method for the assessment of neutron cross sections for Ti in the energy range from a few keV to a few MeV. The measured spectrum in the pile is generally in good agreement with the calculated one from ENDF/B-IV (MAT = 1,286 for Ti) except in the energy range from about 60 keV to a few 100 keV, where the calculation gives considerably lower neutron flux than the measurement.

In order to investigate the cause of this discrepancy between the measured and calculated spectra, the total cross sections for Ti were measured by the transmission method. The results give larger values of total cross sections for Ti by about 30% than ENDF/B-IV below 200 keV, and smaller values by about 10% above 200 keV. These results were ensured at 55 and 147 keV by the measurement using a Si-filtered neutron beam. The calculation based on the measured cross sections shows better agreement with the measured spectrum than that based on ENDF/B-IV. The discrepancy is still observed around 100 keV.

The sensitivity analysis shows the importance of cross sections above 1 MeV and elastic cross sections in the resonance energy region to solve the disagreement between the measured spectrum and the calculated one.     

Neutron Total Cross Sections of 239Pu from Transmission Measurements in the Energy Range of 1–500keV

The average neutron total cross sections of ²³⁹Pu were obtained in the energy range of 1~500 keV from the high resolution transmission measurements performed by Harvey et al. at the Oak Ridge Electron Linear Accelerator (ORELA). In the energy range of 1~10 keV, the average effective cross sections of three samples were extrapolated to the total cross section for zero sample thickness. Above 10 keV the resonance self-shielding corrections to the effective cross sections of the thick sample were calculated by simulation of the cross sections from the resonance parameters. The results are given with 2% to 4% accuracy in the energy range of 1~10 keV and with better than 1% accuracy in the energy range above 10 keV. They are particularly useful to meet the needs of accurate experimental data in the energy range of 1~50 keV.     

K-shell ionization cross sections of Cl and Lα, Lβ X-ray production cross sections of Ba by 6-30 keV electron impact

The absolute K-shell ionization cross sections of Cl and L_α, L_β X-ray production cross sections of Ba by 6-30 keV electron impact have been measured. The target was prepared by evaporating the thin film of compound BaCl₂ to the thick pure carbon substrate. The effects of multiple scattering of electrons penetrating the target films, electrons reflected from the thick pure carbon substrates and Bremsstrahlung photons produced when incident electrons impacted on the targets are corrected by using Monte Carlo method. For Ba L-shell X-ray characteristic peaks, the spectra were fitted by using spectrum-fitting program ALLFIT to extract more accurately the L_α and L_β peak counts. The experimental results, reported here for the first time in the energy region of 6-30 keV, were compared with some theoretical results developed recently.     

Measurement of keV-Neutron Capture Cross Section of 96Zr

The neutron capture cross section of ⁹⁶Zr at incident neutron energies from 15 to 100 keV has been measured by the time-of-flight method. Capture γ-rays were detected with an anti-Compton NaI(Tl) spectrometer, and the pulse-height weighting technique was applied to derive the neutron capture cross section. The present measurement provided the capture cross section as a function of incident neutron energy in the keV region. The results were compared with previous measurements and cross section data in the evaluated nuclear data libraries, JENDL-4.0, JENDL-3.3, ENDF/B-VII.0, and ENDF/B-VI.8. The present results revealed considerable underestimation of the evaluated cross sections in the high-energy region of 35–100 keV.     

Ar~+/Ar,O_2~+/O_2 and N_2~+/N_2 Elastic Momentum Collision Cross Sections: Calculation and Validation Using the Semi-Classical Model

The aim of this paper is to obtain relevant sets of collision cross sections of the parent ions in low pressure discharges in argon, oxygen, and nitrogen, i.e., Ar＋ in Ar, O2＋ in O2 and N2＋ in N2. These ion data are first discussed and then validated from comparisons between the calculated transport coefficients and those measured in the literature. The elastic momentum transfer collision cross sections are determined from a semi-classical approximation for the phase shift calculation based on a 12-6-4 inter-particle potential while ion transport coefficients are determined versus the reduced electric field from Monte Carlo simulations.     

New Evaluation of Neutron Nuclear Data for Zinc Isotopes

New evaluation of neutron-induced nuclear data for five stable isotopes of zinc (mass numbers A = 64, 66, 67, 68, and 70) was consistently carried out in the incident neutron energy range from 10^?5 eV up to 20MeV. In the low energy region up to about 100keV, the resonance parameters were evaluated by taking account of the available measured data. In the fast neutron region, the comprehensive calculations with nuclear reaction models, in which compound, preequilibrium, and direct processes are taken into account, were performed to estimate cross sections for various reactions and double differential cross sections of emitted neutrons and γ-rays. The comparisons of the evaluated cross sections with the experimental data and existing evaluated nuclear data libraries are made and show a good agreement with the measurements.     

Proton elastic scattering cross sections of carbon,nitrogen and silicon for backscattering analysis in the energy range 0.7—2.5 MeV

Differential elastic scattering cross sections of 0.7—2.5 MeV protons for carbon, nitrogen and silicon have been determined at a scattering angle θ = 170°. Results from previous measurements near θ = 170° show large variations, of the order of 10–30% in the nonresonant regions. The purpose of the present investigations is to tabulate cross section data for backscattering analysis at a single scattering angle for many elements. Proton backscattering in the non-Rutherford energy region is more sensitive in the detection of C, N and many other light elements than other ion beam methods when a high background from the matrix is absent. Proton backscattering by using the present scattering cross sections and computer data analysis are outlined. The possible interference from other nuclear reactions is considered.     

Measurement of keV-Neutron Capture Cross Sections and Capture Gamma-Ray Spectra of 209Bi

The capture cross sections and capture γ-ray spectra of ²⁰⁹Bi were measured in a neutron energy region from 5 to 80keV and at 520 keV, using pulsed keV neutrons from the ⁷Li(p, n)⁷Be reaction and a time-of-flight method. The capture γrays from a bismuth or standard gold sample were detected with a large anti-Compton NaI(Tl) spectrometer. The capture yield of the bismuth or gold sample was obtained by applying a pulse-height weighting technique to the corresponding capture y-ray pulse-height spectrum. The derived capture cross sections from 5 to 80 keV were in good agreement with recent measurements, but that at 520 keV was about half of previous measurements. This large discrepancy at 520 keV was ascribed to the incorrect background-subtraction in the previous measurements from a comparison between the present and previous capture γray spectra. Strong transitions from the capture states to low lying states of ²¹⁰Bi were observed in the present γray spectra. The multiplicities of observed y rays were obtained from the γray spectra.     

Measurement of the cross sections of the reactions 14N(n, α)11B and 14N(n, t)12C at neutron energies 5.45–7.2 MeV

The cross sections of the reactions ¹⁴N(n, α)¹¹B and ¹⁴N(n, t)¹²C have been measured for neutron energies 5.46–7.2 MeV. The neutrons are generated in the reaction D(d, n) on a solid titanium target. The work employs digital spectrometry. The charged-particle detector is a pulsed ionization chamber with a Frisch grid, filled with a kyrpton-nitrogen mixture. The cross sections are measured for four groups of α particles α₀, α₁, α₂, and α₃ from the reaction ¹⁴N(n, α)¹¹B and for tritium from the reaction ¹⁴N(n, t)¹²C. The energy resolution of the spectrometer was 60 keV. The errors in determining the cross sections for the reactions (n, α) and (n, t) are 10–15%. The measurement results are compared with the ENDF/V VI evaluation. Good agreement is obtained in the neutron energy range 5.45–6.5 MeV. At higher energies, the discrepancy reaches 30%. __________ Translated from Atomnaya énergiya, Vol. 101, No. 4, pp. 307–311, October, 2006.