海洛因的傅里叶红外吸收谱

给出海洛因和鸦片的傅里叶红外吸收实测谱。根据吸收峰的位置，计算出海洛因的基本声子能量：ＥＬＯ＝０．０４８６ｅＶ，ＥＴＯ１＝０．０５５５ｅＶ，ＥＴＯ２＝０．０６１６ｅＶ，ＥＬＡ＝０．０２５７ｅＶ，ＥＴＡ１＝０．００９７ｅＶ，ＥＴＡ２＝０．０１３４ｅＶ。这些声子按照不同的组合方式，形成海洛因的全部傅里叶红外吸收峰。     

16O＋24Mg反应全熔合激发函数的类共振结构

本工作用位置灵敏的△Ｅ－Ｅ望远镜系统，入射能量长为１．０ＭｅＶ，测量了５５－９０ＭｅＶ１６Ｏ＋２４Ｍｇ反应全熔全激发函数，实验结果表明，这个反应的全熔合激发函数不是平滑的，存在着宽结构。峰位在ＥＣＭ＝３４．２，３７．８，４０．６，４３．８和４６．６ＭｅＶ。当ＥＣＭ＞４８ＭｅＶ时。激发函数的结构消失了。     

低压－金属有机物汽相外延生长的Ga＿（1－x）In＿xAs／InP激光器中深能级的研究

应用深能级瞬态谱（ＤＬＴｓ）技术详细研究低压－金属有机物汽相外延（ＬＰ－ＭＯＶＰＥ）生长的Ｇａ＿（０．４７）Ｉｎ＿（０．５３）Ａｓ／Ｉｎｐ量子阱、宽接触和质子轰击条形异质结激光器中的深能级。样品的ＤＬＴＳ表明，在宽接触激光器的ｉ－Ｇａ＿（０．４７）Ｉｎ＿（０．５３）Ａｓ有源层里观察到Ｈ１（Ｅ＿ｖ＋０．０９ｅＶ）和Ｅ１（Ｅ＿ｃ－０．３５ｅＶ）陷阱，它们可能分别与样品生长过程中扩散到ｉ－Ｇａ＿（０．４７）Ｉｎ＿（０．５３）Ａｓ有源层的Ｚｎ和材料本身的原生缺陷有关。而条形激光器的ｉ－Ｇａ＿（０．４７）Ｉｎ＿（０．５３）Ａｓ有源层的Ｈ２（Ｅ＿ｖ＋０．１１ｅＶ）和Ｅ２（Ｅ＿ｖ－０．４２ｅＶ）陷阱则可能是Ｈ１和Ｅ１与质子轰击引起的损伤相互作用的产物。     

Si／Ge应变层超晶格的椭偏光谱

测量了几种不同组分的（Ｓｉ）Ｍ／（Ｇｅ）Ｎ应变超晶格材料的椭偏光谱（２．０～５．０ｅＶ），并得到了其介电函数谱；应用介电函数的临界点理论，研究了（Ｓｉ）Ｍ／（Ｇｅ）Ｎ应变超晶格材料的光学性质。发现短周期Ｓｉ／Ｇｅ应变超晶格除了具有明显的Ｅ１和Ｅ２带间跃迁外，还存在与应力和超晶格能带的折迭效应有关的跃迁峰，其能量分别位于２．３～３．０ｅＶ和３．３～４．０ｅＶ范围内     

低压-金属有机物汽相外延生长的Ga1-xInxAs/InP激光器中深能级的研究

应用深能级瞬态谱（ＤＬＴｓ）技术详细研究低压－金属有机物汽相外延（ＬＰ－ＭＯＶＰＥ）生长的Ｇａ_０．４７Ｉｎ_０．５３Ａｓ／Ｉｎｐ量子阱、宽接触和质子轰击条形异质结激光器中的深能级。样品的ＤＬＴＳ表明，在宽接触激光器的ｉ－Ｇａ_０．４７Ｉｎ_０．５３Ａｓ有源层里观察到Ｈ１（Ｅ_ｖ＋０．０９ｅＶ）和Ｅ１（Ｅ_ｃ－０．３５ｅＶ)陷阱，它们可能分别与样品生长过程中扩散到ｉ－Ｇａ_{０．４ 关键词：}     

^229Ra的衰变纲图

用１４ＭｅＶ中子轰击钍靶，通过＾２３２Ｔｈ（ｎ，α）＾２２９Ｒａ反应产季了＾２２９Ｒａ，由放射化学分离技术从被照靶物质中分离出＾２２９Ｒａ活性，利用γ（Ｘ）谱学方法，首次观测到了＾２２９Ｒａ的能量为１４．５，１５．６，１８．８，２１．８，２２．５，４４．０，４７．５，５５．０，６３．０，６９．６，９３．６，９４．１，９８．５，１０２．２，１０４．５，１０６．１，１６１．１和１７１．５ｋｅＶ的１８条     

ICP－AES法测定人体血清中的Al、Be、Cu、Mn、Mo、V

建立了用ＩＣＰ－ＡＥＳ同时测定人体血清中的Ａｌ、Ｂｅ、Ｃｕ、Ｍｎ、Ｍｏ、Ｖ等六种元素的方法。在我们的设备上，检出限对Ａｌ、Ｃｕ、Ｍｏ为１～３μｍｏｌ／Ｌ，而对Ｂｅ、Ｍｎ、Ｖ为０．１～０．３μｍｏｌ／Ｌ。这六种元素的回收率在１００±２０％之间。     

ICP—AES法测定人体血清中的Al,Be,Cu,Mn,Mo,V

建立了用ＩＣＰ－ＡＥＳ同时测定人体血清中的Ａｌ，Ｂｅ，Ｃｕ，Ｍｎ，Ｍｏ，Ｖ等六种元素的方法。在我们的设备上，检出限对Ａｌ，Ｃｕ，Ｍｏ为１－３μｍｏｌ／Ｌ，而对Ｂｅ，Ｍｎ，Ｖ为０．１－０．３μｍｏｌ／Ｌ。这六种元素的回收率在１００±２０％之间。     

关于l／η（1440）的结构分析

本文通过对Ｊ／ψ辐射衰变到Ｋ＋Ｋ－πＯ和终态中ｉｏｔａ能区的振幅分析，发现ｉｏｔａ峰下有一个０－＋共振态（Ｍ＝１４６７±３ＭｅＶ，＝８９±６ＭｅＶ）和两个１＋＋共振态（Ｍ＝１４３５±３ＭｅＶ，＝５９±５ＭｅＶ；Ｍ＝１４９７±２ＭｅＶ，＝４４±７ＭｅＶ），分别对应于η（１４４０），ｆ１（１４２０）和ｆ１（１５１０）．     

~（56，57）Fe，~（59）Co（α，d）核反应及拉长态性质的实验研究

利用△Ｅ—Ｅ望远镜及Ｑ３Ｄ磁谱仪，在ＨＩ－１３串列加速器提供的３５ＭｅＶα离子束轰击下，测量５６，５７Ｆｅ，５９Ｃｏ（α，ｄ）５８、５９Ｃｏ，６１Ｎｉ核反应的精细能谱和微分截面角分布，微观ＤＷＢＡ近似用来分析实验数据．在５６Ｆｅ（α，ｄ）５８Ｃｏ核反应观测的９个强激发能级中，重点分析和讨论了６．７９ＭｅＶ和６．４ＭｅＶ能级的性质，观测到迄今所能看到的最高拉长组态（１ｇ９／２，１ｇ９／２）９和首次确认了６．４ＭｅＶ能级Ｊπ＝１＋．在５７Ｆｅ，５９Ｃｏ（α，ｄ）核反应测量中，未看到孤立强激发能级，它意味着强度分散在许多能级上，以致看不到孤立拉长态存在的实验证据．     

Sensitization of ZnO photoconductivity by chemical modification of surface states

Surface States on ZnO have been investigated through their effect on photoconductivity. Low energy photons (0·7 ～ 1·5 eV) are found to induce a feeble photocurrent in ZnO which is attributable to the direct electron injection from surface levels to the conduction band. A definite correlation has been found between the i.r. induced photocurrent and the intrinsic or the dye sensitized photocurrent excited by UV or visible radiation. It is proposed that phthalic anhydride on ZnO modifies the distribution of surface levels, by a chemical interaction with chemisorbed oxygen. Surface levels originating in chemisorbed oxygen ions are transformed by phthalic anhydride into new levels which are shallower but thermally more stable. These traps are found to enhance the photoconductivity of ZnO. The chemical nature of them and the mechanism of sensitization are discussed.     

Thermoluminescence of (ZnS∶CdS∶Ag∶Ni∶Co) phosphors

The doping of (ZnSCdSAgNi) phosphors with cobalt impurity results in new phosphors with thermoluminescence curves showing five distinct peaks. Four of these peaks are associated with chlorine, cadmium, cobalt and nickel impurities and have energy depths of 0·26 eV, 0·52 eV, 0·53 eV and 0·78 eV respectively. The fifth peak, appearing at high cobalt concentrations, has an energy depth of 1·09 eV and is attributed to the formation of (Co⁺⁺ - Ag^–) associates. The emitted thermoluminescence consists of two bands: one in the yellow and the other in the red spectral region. The yellow band subsumes the chlorine, cadmium and cobalt peaks and is due to recombination processes occurring through silver centres. The red band, on the other hand, includes the nickel and the (Co⁺⁺-Ag^–) peaks. The appearance of the nickel peak in the red band is explained by recombination processes at energy levels created by the nickel impurity centres.     

Optical absorption edge in SnS

Optical absorption in single crystals of tin sulfide has been studied at many temperatures between 100 and 300 °K, in the wavelength range 2·2–0·8 μ. From the interference fringe patterns the absorption coefficient, reflection coefficient and index of refraction as a function of wavelength were determined for two light polarizations (ε∥a and ε∥b). From an analysis of the data, indirect band gaps of 1·142 and 1·095 eV were found for the two directions of polarization. Also it was found that the phonon assisted transitions required the participation of two phonons at different energy thresholds with energies 0·033 or 0·038 eV and 0·082 or 0·113 eV, with reference to the two axis. The temperature dependence of the indirect band gap for each direction of light polarization is linear with a slope ?4·05 × 10^?3eV and ?4·37 × 10^?3 eV respectively.     

High resolution core and valence band XPS spectra of non-conductor pyroxenes

High resolution core level and valence band (VB) X-ray photoelectron spectra (XPS) of the non-conductor pyroxene minerals, bronzite ((Mg_0.8,Fe_0.2)₂Si₂O₆) and diopside (Ca(Mg_0.8Fe_0.2)Si₂O₆) have been obtained with the Kratos magnetic confinement charge compensation which minimizes differential charge broadening. Observed Si 2p, O 1s, Mg 2p and Ca 2p total linewidths are all about 1.3 eV, very similar to those observed previously with the same instrument for SiO₂ and olivines ((Mg,Fe)₂SiO₄); and we consider that these widths are within 0.05 eV of the minimum room temperature linewidths for these samples with the experimental resolution of this instrument of 0.35 eV. These linewidths are all determined by vibrational broadening due to the M-O symmetric stretch in the ion states. The Si 2p binding energies (BE) are intermediate between the quartz and olivine Si 2p binding energies; but the O 1s spectra resolve the bridging oxygen (BO) and non-bridging oxygen (NBO) in the unit, with the NBO O 1s very close in BE to the O in olivine, and the BO very close to the BO in SiO_2. Indeed in both diopside and bronzite, it is possible to separate the three structurally inequivalent O atoms in the O 1s spectra: the BO at a BE of about 532.6 eV, a NBO peak from the MgOSi moiety (Mg in the M1 site) at about 531.3 eV, and a NBO peak at 531 eV from the CaOSi or the FeOSi moieties (Ca and Fe in the M2 site). The O 1s BE increases with the increase in the electronegativity Ca < Mg < Fe < Si. Moreover, the linewidths of these peaks increase when Fe and Mg are both present in either M1 (diopside) or M2 (bronzite) sites.The valence band spectra for the two pyroxenes are rather similar, and quite different from the VB spectra of quartz and olivines. The dispersion of the pyroxene VB spectra is intermediate between the VB spectra of quartz and olivines; the valence band spectrum of pyroxenes are more dispersed than in olivines by about 1.5 eV but less dispersed than quartz by about 1.5 eV. These VB spectra can be assigned using the previous olivine VB spectra and high quality pseudopotential density functional theoretical calculations in the generalized gradient (GGA) approximation. As for the olivine VB spectra, the Fe 3d t_2g and e_g orbitals in M1 and M2 sites of the pyroxene are located at the top of the pyroxene valence band, and the BE of the Fe 3d peaks from M1 are about 0.7 eV smaller than the Fe 3d peaks in M2. The theoretical XPS valence band spectra using the theoretical density of states and the Gelius intensity approximation are is in good semi-quantitative agreement with the experimental spectra. This intermediate dispersion of pyroxenes is due to the partial polymerization of the Si-O units in pyroxenes, and the intermediate charge on the Si atoms as indicated by the Si 2p BE.     

Band gap states of V and Cr in 6H-silicon carbide

Ti, V and Cr in n-type 6H-SiC were investigated by radiotracer deep level transient spectroscopy (DLTS). Doping with the radioactive isotopes ⁴⁸V and ⁵¹Cr was done by recoil implantation followed by annealing (1600 K). Repeated DLTS measurements during the elemental transmutation of these isotopes to ⁴⁸Ti and ⁵¹V respectively revealed the corresponding concentration changes of band gap states. Thus, three levels were identified in the band gap: a Cr level at 0.54 eV and two V levels at 0.71 and 0.75 eV below the conduction band edge. There are no deep levels of Ti in the upper part of the band gap. Received: 28 April 1997/Accepted: 16 May 1997     

Electron-stimulated desorption of lithium atoms from oxidized molybdenum surface

The yield and energy distributions of lithium atoms upon electron-stimulated desorption from lithium layers adsorbed on the molybdenum surface coated with an oxygen monolayer have been measured as functions of the impact electron energy and lithium coverage. The measurements are performed using the time-of-flight technique and a surface ionization detector. The threshold of the electron-stimulated desorption of lithium atoms is equal to 25 eV, which is close to the ionization energy of the O 2s level. Above a threshold of 25 eV, the yield of lithium atoms linearly increases with an increase in the lithium coverage. In the coverage range from 0 to 0.45, an additional threshold is observed at an energy of 55 eV. This threshold can be associated with the ionization energy of the Li 1s level. At the electron energies above a threshold of 55 eV, as the coverage increases, the yield of lithium atoms passes through a maximum at a coverage of about 0.1. Additional thresholds for the electron-stimulated desorption of the lithium atoms are observed at electron energies of 40 and 70 eV for the coverages larger than 0.6 and 0.75, respectively. These thresholds correlate with the ionization energies of the Mo 4s and Mo 4p levels. Relatively broad peaks in the range of these thresholds indicate the resonance excitation of the bond and can be explained by the excitation of electrons toward the band of free states above the Fermi level. The mean kinetic energy of the lithium atoms is equal to several tenths of an electronvolt. At electron energies less than 55 eV, the energy distributions of lithium atoms involve one peak with a maximum at about 0.18 eV. For the lithium coverages less than 0.45 and electron energies higher than 55 eV, the second peak with a maximum at 0.25 eV appears in the energy distributions of the lithium atoms. The results obtained can be interpreted in the framework of the Auger-stimulated desorption model, in which the adsorbed lithium ions are neutralized after filling holes inside inner shells of the substrate and lithium atoms.     

The electron energy loss spectrum of LiF in the band gap region

The eels of LiF has been measured in the range 0–18 eV with primary beam energies 50 eV and 1.5 keV. Four peaks are clearly resolved in the band gap region at room temperature. The amplitude of the three lower energy loss peaks was found to depend on beam exposure and temperature. It is concluded that the lowest energy peak arises at a beam induced defect, that the next two peaks arise in lithium metal liberated by the electron beam and that the peak nearest to the band edge is due to an intrinsic surface excitation.     

Photoluminescence from gold centre in silicon

A sharp line structure attributable to ?honon assisted radiative emission has been observed in the low temperature photoluminescence spectra from deep centres in bulk samples of gold-doped silicon. The entire luminescence band which peaks near 0.78 eV is attributed to transitions of conduction electrons towards the gold-related donor level.     

掺Er/Pr的GaN薄膜深能级的研究

利用深能级瞬态谱(DLTS)、傅里叶变换红外光谱(FT-IR)对GaN以及GaN掺Er/Pr的样品进行了 电学和光学特性分析.研究发现未掺杂的GaN样品只在导带下0.270eV处有一个深能级；GaN注 入Er经900℃,30min退火后的样品出现了四个深能级，能级位置位于导带下0.300 eV,0.188 eV,0.600 eV 和0.410 eV；GaN注入Pr经1050℃,30min退火后的样品同样出现了四个深能级 ，能级位置位于导带下0.280 eV,0.190 eV,0.610 eV 和0.390 eV；对每一个深能级的来源 进行了讨论.光谱研究表明，掺Er的GaN样品经900℃,30min退火后，可以观察到Er的1538nm 处的发光，而且对能量输运和发光过程进行了讨论. 关键词： GaN Er Pr 深能级     

第一性原理下铜锰共掺铌酸锂晶体的电子结构和吸收光谱

采用基于密度泛函理论的第一性原理研究了Cu、Mn单掺及共掺LiNbO3晶体的电子结构和光学性质.结果显示,Cu、Mn掺杂LiNbO_3晶体禁带中的杂质能级分别由Cu 3d轨道、Mn 3d轨道贡献;各掺杂体系的带隙均较纯LiNbO_3晶体变窄.共掺晶体中Cu离子形成了较单掺时更浅的能级中心,并在2.87eV处有较强的吸收峰;Mn离子在1.73eV附近的吸收较单掺时减弱且中心略有偏移,在2.24eV处的非光折变峰与Mn~(3+)相关,这对吸收峰的变化被认为与Cu、Mn间电子转移相联系.相对Cu、Fe共掺LiNbO_3晶体,Cu、Mn共掺LiNbO_3晶体可以通过适当提高Cu离子浓度,来改善存储参量中的动态范围和记录灵敏度.由于同一深能级掺杂离子伴以不同浅能级掺离子将呈现出不同的吸收特征并影响存储性能,在共掺离子的配搭选择时对各待选配搭的模拟计算非常必要.