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Atom location by channeling-enhanced microanalysis (ALCHEMI) is a technique to obtain atom-site-specific information on constituent elements in a crystalline sample by acquiring a set of core electron transition spectra while tilting the incident beam. This methodology has been extended to a more quantitative technique called high-angular-resolution electron-channeled X-ray/electron spectroscopy (HARECXS/HARECES). There is a growing demand for analyzing smaller areas, such as small particles and multilayers. However, the minimum size of a region of interest probed by the present hardware-assisted automated HARECXS/HARECES scheme is limited to no smaller than 1 µm, not only by the size of the electron probe and its convergence angle but also by the movement of the probe position associated with the beam tilt due to aberrations of the hardware system. Herein, QED (quantitative electron diffraction), a commercial plug-in working on an integrated software platform, Gatan Microscopy Suite, was modified to enable the calibration and control of the probe to resolve the aforementioned limitation. In addition, a more sophisticated scheme for QED was developed to realize the ALCHEMI method for energy-dispersive X-ray spectroscopy, electron energy-loss spectroscopy or both concurrently. This allows access to ALCHEMI and its derivative methods, automatically executed with any type of current PC-controlled commercial microscope on an area as small as 30 nm, without modifying the hardware system.

ReciPro is a comprehensive multipurpose crystallographic program equipped with an intuitive graphical user interface (GUI), and it is completely free and open source. This software has a built-in crystal database consisting of over 20 000 crystal models, and the visualization system can seamlessly display a specified crystal model as an attractive three-dimensional graphic. The comprehensive features are not confined to these crystal model databases and viewers. It can smoothly and quantitatively simulate not only single-crystal and/or polycrystalline (powder) diffraction patterns of X-ray, electron and neutron diffraction of a selected crystal model, based on the kinematic scattering theory, but also various electron diffraction patterns and high-resolution transmission electron microscopy (TEM) images, based on the dynamical scattering theory. The features of stereographic projection of crystal planes/axes to explore crystal orientation relationships and the semi-automatic diffraction spot indexing function for experimental diffraction patterns assist diffraction experiments and analyses. These features are linked through a user-friendly GUI, and the results can be synchronously displayed almost in real time. ReciPro will assist a wide range of crystallographers (including beginners) using X-ray, electron and neutron diffraction crystallography and TEM.

Minerals on airless bodies exhibit characteristic spectral features such as darkening and reddening. Such space weathering is mainly due to hydrogen-ion irradiation by the solar wind and to micrometeorite impacts. Because of the reactivity of hydrogen, the associated H-implantation into O-bearing minerals can lead to the formation of new chemical bonds and may contribute to formation of water. However, laboratory studies still conflict about production efficiency of water and relevant H-bearing molecules such as OH formed by the H-ion irradiation. The production efficiency of the molecules within minerals may be influenced by short-range structural order of the host minerals. It is thus important to clarify how the implanted H interacts with various irradiation defects produced by H-ion bombardment. Here, we investigated H-ion-irradiated alumina (Al2O3), one of the most basic oxides, using scanning/transmission electron microscopy (S/TEM) and electron energy-loss spectroscopy (EELS). The TEM images revealed dense dislocations, nanoscale voids and nanoscale cracks—instead of amorphization—in the region subject to high energy deposition. Our analyses by STEM–EELS hyperspectral imaging (HSI) isolated a few essential spectral components, suggesting that chemical interactions between the implanted H and the host alumina resulted in local generation of OH species rather than amorphization. We also found a spectral feature which may be explained by H2 gas, presumably remaining in the nanovoids, most of which escaped through fractures formed by the coalescence of the high-pressure H2 nanobubbles. Such fractures/crack surfaces can act as additional reactive sites for the formation of the OH species. The present results strongly imply that H+ irradiation can be a source of water in minerals in various astrophysical conditions. The present methodology can be applied to a wide range of extraterrestrial materials, such as regolith grains, interplanetary-dust particles, and/or presolar grains in primitive meteorites.

Photocatalytic water splitting reaction attracts considerable attention owing to their potential application to generate H2 gas from H2O by using solar energy. However, further activity enhancement...

In this study, we applied electron energy-loss magnetic chiral dichmism (EMCD), an electron counterpart of X-ray magnetic circular dichmism (XMCD), to a network nanostructured FePt L1(0) ordered alloy film to examine the relative orientation of magnetic moments between neighboring Fe and Pt atoms using the Fe-M-2,M-3, Pt-O-2,O-3, and Pt-N-6,N-7 semi-core excitation spectra with transmission electron microscopy and electron energy-loss spectroscopy. EMCD signals were successfully extracted from a large number of spectra using a dedicated data analysis procedure to obtain sufficient noise statistics. Results showed that the relative sign relation of the EMCD signals between the Fe and Pt absorption edges was consistent with that of the theoretical dielectric tensor while assuming that parallel magnetic moments exist between neighboring Fe and Pt. We believe the results of this study can be applied to alloys with different nanostructures to determine whether the spin configuration depends on the size and geometry of the nanostructures.

Extension of the focal depth of a sub-nanometer-sized electron probe in a scanning transmission electron microscope was demonstrated using an electron Bessel beam. We observed atomically-resolved annular dark-field scanning transmission electron microscope images of SrTiO3 in the [001] direction with defocus using an electron quasi-Bessel beam generated by a ring-shaped aperture in an aberration-corrected probe-forming system. The experimental results show that the defocus range over which images with a 0.2 nm spatial resolution can be acquired using the electron quasi-Bessel beam is three times longer than the corresponding defocus range for a conventional beam.

A novel elemental and chemical analysis scheme based on electron-channeling phenomena in crystalline materials is introduced, where the incident high-energy electron beam is rocked with the submicrometric pivot point fixed on a specimen. This method enables us to quantitatively derive the site occupancies and site-dependent chemical information of impurities or intentionally doped functional elements in a specimen, using energy-dispersive X-ray spectroscopy and electron energy-loss spectroscopy attached to a scanning transmission electron microscope, which is of significant interest to current materials science, particularly related to nanotechnologies. This scheme is applicable to any combination of elements even when the conventional Rietveld analysis by X-ray or neutron diffraction occasionally fails to provide the desired results because of limited sample sizes and close scattering factors of neighboring elements in the periodic table. In this methodological article, we demonstrate the basic experimental procedure and analysis method of the present beam-rocking microanalysis.

Nickel-based layered rock-salt cathode materials for lithium-ion secondary batteries have drawn considerable attention due to their high energy capacity, lower cost, and better environmental compatibility than other current potential materials. As the nickel content increases, however, these materials suffer from significant capacity fading during charge-discharge cycles at elevated temperatures. While the capacity deterioration and poor cycling stability are mainly because of the formation of NiO-like rock-salt structures at the surface of active materials, the degradation mechanisms have not been fully investigated. In this study, to clarify the process of formation of inactive NiO-like structures, the degradation mechanism of a cathode-active material, namely, LiNi 0.80 Co 0.15 Al 0.05 O 2 (NCA) is studied after a single charge–discharge cycle, by using site-selective energy-dispersive X-ray spectroscopy associated with transmission electron microscopy. It is confirmed that cation mixing occurs between the lithium- and transition metal-sites of the LiMO 2 (M = transition metals) layered rock-salt structures during the transition to partially ordered transition states and then to the final NiO-like disordered rock-salt structures. Further, the volume fractions of the partially/fully disordered phases in the NCA primary particles are quantitatively estimated.

This paper demonstrates how Signal Subspace Sampling (SSS) is an effective pre-processing step for Non-negative Matrix Factorization (NMF) or Vertex Component Analysis (VCA). The approach allows to uniquely extract non-negative source signals which are orthogonal in at least one observation channel, respectively. It is thus well suited for processing hyperspectral images from X-ray microscopy, or other emission spectroscopies, into its non-negative source components. The key idea is to resample the given data so as to satisfy better the necessity and sufficiency conditions for the subsequent NMF or VCA. Results obtained both on an artificial simulation study as well as based on experimental data from electron-microscopy are reported.

Knowledge of the location and concentration of impurity atoms doped into a synthesized material is of great interest to investigate the effect of doping. This would usually be investigated using X-ray or neutron diffraction methods in combination with Rietveld analysis. However, this technique requires a large-scale facility such as a synchrotron radiation source and nuclear reactor, and can sometimes fail to produce the desired results, depending on the constituent elements and the crystallographic conditions that are being analysed. Thus, it would be preferable to use an element-selective spectroscopy technique that is applicable to any combination of elements. We have established a quantitative method to deduce the occupation sites and their occupancies, as well as the site-dependent chemical states of the doped elements, using a combination of transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, and electron energy-loss spectroscopy (EELS). The method is based on electron channelling phenomena where the symmetries of the Bloch waves excited in a crystal are dependent on the diffraction condition or incident beam direction with respect to the crystal axes. By rocking the incident electron beam with a fixed pivot point on the sample surface, a set of EDX/EELS spectra are obtained as a function of the beam direction. This is followed by a statistical treatment to extract the atom-site-dependent spectra, thereby quantitatively enabling the estimation of the site occupancies and chemical states of the dopants. This is an extension of the ‘ALCHEMI’ (Atom Location by Channelling Enhanced Microanalysis) method or ‘HARECXS/HARECES’ (High Angular Resolution Channelled X-ray/Electron Spectroscopy), and we further extended the method to be applicable to cases where the crystal of interest contains multiple inequivalent atomic sites for a particular element, applying the precise spectral predictions based on electron elastic/inelastic dynamical scattering theory. After introduction of conceptual aspects of the method, we describe the extension of the method together with the development of the theoretical calculation method. We then demonstrate several useful applications of the method, including luminescent, ferrite, and battery materials. We discuss the advantages and drawbacks of the present method, compared with those of the recently developed atomic column-by-column analysis using aberration-corrected scanning TEM and high-efficiency X-ray detectors.

We propose a magnetic measurement method utilizing a patterned postsample aperture in a transmission electron microscope. While utilizing electron magnetic circular dichroism, the method circumvents previous needs to shape the electron probe to an electron vortex beam or astigmatic beam. The method can be implemented in standard scanning transmission electron microscopes by replacing the spectrometer entrance aperture with a specially shaped aperture, hereafter called a ventilator aperture. The proposed setup is expected to work across the whole range of beam sizes-from wide parallel beams down to atomic resolution magnetic spectrum imaging.

Huge thermal noise owing to the narrow energy bandgap is one of the critical issues for group IV-based photonics in the mid-infrared regime. With this motivation, we examined to form Ge1−xSnx/Ge1−x−ySixSny quantum heterostructures (QHs) by molecular beam epitaxy for realizing resonant tunneling diodes composed of group-IV materials. We confirmed the formation of approximately 2 nm-thick Ge1−xSnx/Ge1−x−ySixSny QHs with atomically flat interfaces by x-ray diffraction and transmission electron microscopy methods. Moreover, by the current density–voltage (J–V) measurement at 10 K, we observed the occurrence of a non-linear distinct hump in the J–V characteristic, which is possibly originated from quantum transport of heavy holes. According to the tunneling transmission spectra simulation result, the hump property would be due to two possible scenarios: a resonant tunneling of heavy holes in the QH and/or a resonance phenomenon that heavy holes pass just above a potential barrier.

Phase-separated glass (PSG) is being used widely for manufacturing scientific apparatus and kitchenware, owing to its advantages of high hardness and heat resistance, which can be attributed to its sea- and island-like structures on the nanoscale. There is a growing demand in the glass industry for methods for evaluating and visualizing the local stress distribution in such glass materials at the nanoscale in order to elucidate their fracture mechanism and to obtain more information to develop even harder glass materials. In this study, we clarified the correlation between the local stress in this type of glass material and its associated nanoscale structure using a nanoelectron probe based on scanning transmission electron microscopy and cathodoluminescence. The peak shift of an emission line corresponding to an intentionally doped rare-earth element was measured based on the piezospectroscopic effect. We found that the sea- and island-like structures, whose origins can be attributed to the difference in the thermal expansion coefficients of the two phases, mutually push each other. This result was confirmed by a simple finite-element method simulation. The present result suggests that the local mechanical properties of PSG can be well described by a coherent elastic continuum consisting of the phases that evolve during thermal treatment.

Inelastic electron scattering is a consequence of mostly Coulomb interaction between electrons in the sample and electron beam and, as such, it is a nonlocal event. In atomic resolution experiments ...

W-type strontium hexagonal ferrite, SrMe2+2Fe3+16O27 (Me2+: divalent cation), is a hard magnetic material that exhibits strong magneto-crystalline anisotropy (MCA), showing saturation magnetization, Ms, approximately 10% higher than that of M-type ferrite, one of the current mainstream materials. It is known that partial substitution of a divalent magnetic, nonmagnetic cations or a combination of both for Me2+ occupying appropriate Fe sites improves MCA and Ms, and it is thus important to investigate which Fe site and how much fraction in each site the dopant atoms are actually substituted for in order to find a guiding principle for further improvements of MCA and Ms. In this study, we have quantitatively determined the occupation sites of Zn2+ in Zn-doped W-type ferrite, SrZn2Fe16O27, using a suite of beam-rocking transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), theoretical dynamical elastic/inelastic electron scattering simulation and statistical analysis, an extended version of high-angular resolution electron channeling X-ray spectroscopy (HARECXS) [1]. The sintered specimen includes small amounts of hetero-phases which hamper the application of more macroscopic methods, such as neutron diffraction and synchrotron radiation. In this statistical beam-rocking TEM-EDX analysis, the intensity variations of characteristic X-ray peaks (incoherent channeling patterns (ICPs)) as functions of the incident beam direction with respect to a crystalline specimen reflect the occupation sites of the elements of interest, applicable to a small crystal grain, and the multivariate linear regression between the ICPs from the trace dopants and host elements allows us to quantitatively evaluate the dopant concentrations and their occupancies on different crystallographic sites [2]. The present material, however, has seven crystallographically inequivalent sites (the 2c as the hexagonal site, the 4e and 4fIV as the tetrahedral sites, and the 4f, 4fVI, 6g and 12k as the octahedral sites in the Wyckoff notation) for Fe, and accordingly the site-specific ICPs of the seven sites cannot be obtained separately. We have developed a scheme combining theoretical prediction of the site-specific ICPs, based on dynamical electron diffraction theory and the statistical atom-location by channeling-enhanced microanalysis (ALCHEMI) method [2] to overcome this difficulty, which was successfully applied to Co-doped M-type ferrite [3]. We have thus applied the scheme to present analysis. Figure 1 shows X-ray ICPs of the Sr-L, Fe-K, O-K and Zn-K lines obtained around the [1-20] zone axis, in which seven Fe sites are definitely separated in the projected atomic structure. The Zn-K ICP looks apparently different from some of the Fe-K ICPs, which qualitatively implies that Zn preferentially occupies some of the specific Fe sites, rather than all of them uniformly. Figure 2(a) shows the theoretical Fe-K ICP of the non-doped SrFe18O27, corresponding to Fig. 1(b), showing sufficiently good agreement with each other. The experimental site-specific Fe-K ICPs for the 12k, 6g, 4fVI, 4fIV, 4f, 4e and 2c sites can be thus obtained by the proportional distribution scheme of the experimental Fe-K ICP, as shown in Figs. 2(b-h), then followed by applying the statistical ALCHEMI method to Zn-K ICP (Fig. 1(d)) and site-specific Fe-K ICPs. Table 1 shows the derived parameters. This quantified result suggests that Zn mainly occupies 4e and 4fIV sites. The estimated Zn concentration of 3.1 atom% is slightly lower than the stoichiometric concentration, which is attributable to a grain-to-grain variation of impurity concentration. Ms arises due to a spontaneous molecular magnetic moment M0, the vector sum of the magnetic moments of Fe3+, Fe2+ and Zn2+ cations of 5μB, 4μB and 0μB, respectively, with the spin orientation considered. M0 was estimated to be 36.0μB and 37.6μB for the cases assuming the estimated Zn concentration and the stoichiometric Zn concentration, respectively. These values are close to the magnetization saturations of 35.0μB [4] and 38.2μB [5] previously reported for a similar W-type ferrite BaZn2Fe16O27. Keywords: EDX; electron channeling; ALCHEMI; HARECXS; W-type ferrite

Nonlocality in spherical-aberration-corrected high-angle annular dark-field (HAADF) scanning transmission electron microscope (STEM) images is theoretically and experimentally examined using the absorption potential describing thermal diffuse scattering (TDS). A detailed comparison between the simulated and the experimentally obtained high-quality HAADF STEM images of an Si(110) bulk structure and a PbTiO3(100)/SrTiO3(100) interfacial structure unambiguously demonstrates the need to use a nonlocal TDS absorption potential. The nonlocality in the TDS absorption potential cannot be ignored in a detailed analysis of spherical-aberration-corrected HAADF STEM images of materials consisting of several heavy elements, although it can be completely disregarded for those consisting of only light elements.

The effect of the chromatic aberration (C(c)) coefficient in a spherical aberration (C(s))- corrected electromagnetic lens on high-resolution high-angle annular dark field (HAADF) scanning transmission electron microscope (STEM) images is explored in detail. A new method for precise determination of the C(c) coefficient is demonstrated, requiring measurement of an atomic-resolution one-frame through-focal HAADF STEM image. This method is robust with respect to instrumental drift, sample thickness, all lens parameters except C(c), and experimental noise. It is also demonstrated that semi-quantitative structural analysis on the nanometer scale can be achieved by comparing experimental C(s)- corrected HAADF STEM images with their corresponding simulated images when the effects of the C(c) coefficient and spatial incoherence are included.

A many-beam dynamical theory for plan-view high-resolution transmission electron microscopy (HRTEM) images of multilayer systems without the limitation of a superlattice cell is proposed. The accuracy of our method is examined by comparing convergent-beam electron-diffraction calculations of Si(011) and HRTEM calculations of a system of epitaxial Al(100) on GaAs(100). Furthermore, this method is applied to CdSe clusters embedded in MgO, where it is revealed that the relative shift of their crystal-lattice planes produces moiré-like fringes.

The quantitative measurement of a crystal bending effect is performed using low-order zone-axis convergent beam electron diffraction (CBED) patterns. Although the accuracy of the present method is inferior to that of the method of using split higher order Laue zone lines, this method enables us to estimate the crystal bending effect at a region very close to the interface and to easily judge whether the crystal bending effect results in a tensile bend or a compressive bend. As an application of the present method, the crystal bending effect at a region close to the SiGe/Si interface was measured. It was found that the crystal bending effect is due to a thin-foil relaxation of almost 0.3 degrees at a region that is approximately 10 nm away from the interface.

The occupation sites and the occupancies of trace dopants in La/Co co-doped Sr-M-type ferrite, SrFe12O19, were quantitatively and precisely determined by beam-rocking energy-dispersive X-ray spectroscopy (EDXS) on the basis of electron-channeling effects. Because the Co atoms, in particular, should be partially substituted for the five crystallographically inequivalent sites, which could be key parameters in improving the magneto-crystalline anisotropy, it is difficult yet intriguing to discover their occupation sites and occupancies without using the methods of large-scale facilities, such as neutron diffraction and synchrotron radiation. In the present study, we tackled this problem by applying an extended statistical atom location by channeling enhanced microanalysis method, using conventional transmission electron microscopy, EDXS and dynamical electron elastic/inelastic scattering theories. The results show that the key occupation sites of Co were the 2a, 4f1 and 12k sites. The quantified occupancies of Co were consistent with those of the previous study, which involved a combination of neutron diffraction and extended X-ray absorption fine structure analysis, as well as energetics considerations based on by first-principles calculations.

In this study, lithium-ion transfer through the electrode/electrolyte interface was examined using a model interface composed of a lithium-ion-conductive ceramic and liquid electrolytes to focus on lithium-ion transfer. Lithium-ion transfer resistances at the interface and their activation energies were evaluated by impedance spectroscopy. The activation energies were quite large and consistent with the interaction between lithium-ion and solvents in an electrolyte as determined by a theoretical calculation.

シールドトンネルの止水性を確保するための水膨張シール材が開発されたのは1980年代前半である. 実施工の結果から止水に対するこのシール材の有効性が確認されて20年近く経過しているが, 長期的な耐久性については十分に評価されていないのが現状である. このため, シール材の耐久性試験方法や水膨張シール材の良否を判定する標準的な基準も定まっていないため, 従来の工事の経験や実験に基づきシール材を選定しているのが実情である. 本研究は, シール材に要求される機能に着目して, 耐久性の評価項目を設定したものであり, これに基づいて, その試験方法を提案するとともに, 現状における水膨張シール材の長期耐久性能を評価したものである.

軟弱粘性土中のシールド建設時における現場計測とそれに対応した遠心模型実験結果により導かれた地盤変形メカニズムの一般性を, 同種地盤における既往5現場計測結果から得られた鉛直ひずみの空間分布形状により検討した. 鉛直ひずみの空間分布形状は, テールボイド沈下区間と後続沈下区間のそれぞれについて, 5現場共に同様な傾向が見られた.その結果, 提示した地盤変形メカニズムで, 5現場で用いられたシールド工法, 裏込め注入方式などの施工条件に関らず, 現場計測より把握できた地盤変形形状の特徴について説明が可能であることを確認した.

シールドテールボイド発生による境界条件, 自重に起因した地盤内応力および土の変形特性の再現が可能な遠心模型実験を用いて, 軟弱粘性土における地盤変形メカニズムの解明を試みた. すなわち, 模型実験の再現性を確認し, 実験上の制約から決まるテールボイド量に関する幾何学的縮尺率の差違の影響評価を行った後, 地盤変形, 間隙水圧挙動および覆工作用圧変化を用いて地盤変形メカニズムを究明した. その結果, 軟弱粘性土におけるシールドテールボイド発生以後の地盤変形メカニズムを三段階のフェイズで説明できることを示した.

シールドトンネルの漏水は, トンネル本体の劣化ばかりでなく, トンネル周辺地山の劣化も引き起こすことから, 漏水の処理にかかるランニングコストもさることながら, トンネルの耐久性を考える上でも重要な問題となっている. トンネル内への漏水が発生する箇所は, そのほとんどがセグメントの継手部であり, 継手面に貼付するシール材の選定が, トンネルの防水には特に重要である. しかしシール材の材質や形状寸法等の選定は, 従来からの経験や実績に基づき行なわれてきたのが実情であり, 止水設計法と呼ばれるようなものは現状では確立されていない. 本研究は現在もっとも多く使用されている水膨張シール材を対象に各種の止水試験を行い, その結果から密封の原理 (パッキン理論) に基づくシール材の止水設計法を提案するものである.

有楽町下部粘性土中の泥土圧式シールド工事の3断面において周辺地盤とセグメントの変位を長期に亘り計測し, 沈下の大半を占めるテールボイド沈下と後続沈下に着目して, 地盤変形挙動を分析した. その結果, テールボイド沈下から後続沈下へ移行する際の変化点はトンネル直上の鉛直歪みに着目すると判別し易いこと, テールボイド沈下区間における地盤変位はトンネル周辺においてトンネル中心に向う二次元弾性論による無限地盤中円孔周りの変位分布に類似した挙動を示すこと, 後続沈下区間における地盤変位はテールボイド沈下区間の変位方向に比ベトンネル下方に向って変位しておりトンネル肩部における圧縮歪みの増加が要因と考えられることが理解できた.

有楽町下部粘性土中の泥土圧式シールド工事の3断面において周辺地盤とセグメントの変位を長期に亘り計測し, シールド通過時, テールボイド発生時およびそれ以後について, トンネル中心線上の鉛直変位を対象に, 特に裏込め注入有無による影響を定量的に検討した. その結果, 適切なチャンバー内圧管理によって切羽部での地盤変位は軽減させられること, セグメント鉛直変位は周辺地盤の鉛直変位に比べ小さいこと, および裏込め注入の有無によってテールボイド沈下量と沈下速度は影響を受けるが, 後続沈下速度には大きな影響を与えないことが明らかとなった.

In this study, we explore the formation mechanisms of different spherical-aberration (C(s))-corrected bright-field (BF) scanning transmission electron microscope (STEM) imaging methods. The C(s)-corrected BF STEM imaging modes are characterised in detail using simulated images and experimental BF STEM images obtained with several types of detectors. The Co₃O₄ specimen results show that the occupancy, the atomic spacing, and the atomic number of the atoms constituting the atomic columns control image formation in BF STEM imaging, which is used to detect light atomic columns. The middle-angle BF STEM image is crucial in image formation by BF STEM imaging.

To simulate the effects of thermal diffuse scattering in the frozen lattice (FL) approximation, we modify the conventional Bloch wave method by applying the classical scattering matrix method. The present simulation method requires that the eigenvalue operation is executed only once for each partial incident wave using the atomic positions of the thermal equilibrium configuration and thus the calculation time decreases drastically. Furthermore, from a comparison of convergent beam electron diffraction (CBED) patterns simulated by the present method with the results of CBED patterns simulated by a multislice method, we confirm that FL approximation can be simulated by the dynamical simulation based on the Bloch wave method.

Simultaneous detection of both light and heavy atomic columns is theoretically and experimentally explored with spherical aberration (Cs)-corrected middle-angle bright-field (MABF) scanning transmission electron microscopy (STEM). Optimized MABF STEM visualizes both light O atomic columns and heavy Sr and Ti–O atomic columns for SrTiO3(001) as distinct bright spots and dark spots with characteristic bright rings, respectively, over practical ranges of the probe-forming lens defocus and sample thickness, although medium-heavy Ti–O atomic columns appear as blurred dark spots. The difference in contrast between heavy and light atomic columns is greater than that of annular BF STEM images. The formation of distinctive bright and dark spots is interpreted simply as the difference in the degrees of localization and inelastic absorption of channeling electrons in individual atomic columns by analyses of convergent wave fields inside the crystal in both real and reciprocal space. In addition, Bloch wave expansion of MABF STEM images suggests that bright rings are formed mainly by 2p-like convergent Bloch wave fields localized on heavy atomic columns.

In this study, we experimentally and theoretically show that the intensities of bright spots in a spherical aberration (C(s))-uncorrected high-angle annular dark-field (HAADF) scanning transmission electron microscope (STEM) image of [011]-oriented Co(3)O(4), which has two different numbers of Co atoms in the projected atomic columns, are reversed with increasing sample thickness. However, C(s)-corrected HAADF STEM images produce intensities that correctly depend on the average number of atoms in the projected atomic columns. From an analysis based on the Bloch-wave theorem, it is found that an insufficient semiangle of the incident convergent beam yields intensities that do not depend on the average atomic number in the atomic columns.

The interface of Ag(In,Ga)Se2 (AIGS) and Cu(In,Ga)Se2 (CIGS) solar cells was investigated by high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) imaging method. It was found from the results that the AIGS film had Ag-rich and Ag-poor layers. The CdS layer in the CIGS solar cell had a denser structure and a better connection with the CIGS layer than the CdS layer in the AIGS solar cell. The lattice between CIGS and CdS was continuous and ordered. However, there were some defects in CdS and the lattice arrangement was distorted at the AIGS/CdS interface in the AIGS solar cell, resulting in the poor performance of the AIGS solar cell compared with the CIGS solar cell.

Lithium-ion transfer at the interface between the lithium-ion-conductive ceramic of La 0.55 Li 0.35 TiO 3 (LLT) and the polymer electrolyte of polyethylene oxide (PEO) complexed with LiCF 3 SO 3 (PEO-LiCF 3 SO 3 ) was studied by ac impedance spectroscopy for the system of Li/PEO-LiCP 3 SO 3 /LLT/PEO-LiCF 3 SO 3 /Li. The impedance ascribed to ion transfer through the interface was observed. The resistance due to the lithium-ion transfer at the interface was larger than those through phases of LLT and PEO-LiCF 3 SO 3 , and the temperature dependence of the interfacial resistances showed Arrhenius-type behavior. The activation energy of the interfacial resistances was larger than those for lithium-ion conduction in LLT and PEO-LiCF 3 SO 3 . The design of the ion-conductive ceramic and the polymer composite electrolytes is discussed based on the results.

Four of 12 monoclonal antibodies (MoAbs) directed to different epitopes in the extracellular domain of the human colony-stimulating factor-1 receptor (CSF-1R, the c-fms proto-oncogene product) specifically inhibit CSF-1 binding to receptor-bearing cells. All four antibodies abrogated CSF-1-dependent colony formation by human bone marrow-derived macrophage precursors and by mouse NIH-3T3 cells expressing a transduced human c-fms gene. In addition, one of these antibodies (designated MoAb 2–4A5) interfered with the ligand-independent proliferation of NIH-3T3 cells transformed by an oncogenic, mutant c- fms allele. Unlike CSF-1 itself, neither MoAb 2–4A5 nor the other three inhibitory antibodies (MoAbs 12–2D6, 12–3A1, and 12–3A3) induced CSF-1R internalization or degradation. These antibodies should prove useful not only for identifying and quantitating CSF-1R on receptor-bearing cells but for abrogating specific receptor signals that govern the proliferation and survival of human mononuclear phagocytes.

Seroconversion to human cytomegalovirus (H-CMV)-specific antigens was observed in 8 out of 9 renal transplant recipients. In 7 of the 8 recipients antibody to "pre-early nuclear antigens" (PENA), which are detectable in human embryonic lung cells within 1 hr of H-CMV infection by anti-complement immunofluorescence staining, developed concomitantly with the increase in other antibodies including anti-early antigens (EA), anti-nuclear inclusions (NI), and complement-fixing (CF) antibody in 1--2 months after transplantation. About 1 year later, anti-PENA and anti-EA titers were concomitantly decreased in 2 recipients, whereas anti-NI and CF antibody titers were maintained at elevated levels in all the seroconverted recipients. These results support the idea that the development of antibody to PENA, like antibody to EA, may represent a current or recent infection with (or reactivation of) H-CMV. In one patient, antibody to PENA did not develop through the observation period despite increases in antibody to EA and other antibodies; this lends support to immunological distinctness of PENA from EA.

Antibodies reactive with O-phosphotyrosine (PTYR) were detected in 60 out of 621 inpatients, with high frequencies in hematologic and lung malignancies, hepatic diseases, cerebrovascular diseases, and autoimmune diseases. Affinity-purified antibodies proved capable of recognizing PTYR-containing proteins in a human carcinoma cell line, A431, both by immunofluorescent staining and by immunoaffinity chromatography, but had no detectable affinity for phosphorylated serine or threonine, or for the nucleotides tested. In these respects, the antibodies observed in human sera were indistinguishable from anti-PTYR antibodies raised experimentally in rabbits or mice.

To facilitate the identification of phosphotyrosine (P-tyr)-containing proteins, rabbit polyclonal antibodies and mouse monoclonal antibody specifically reactive to P-tyr were prepared by hyperimmunizing the animals with P-tyr-conjugated bovine serum albumin or poly-L-lysine. As determined by a solid-phase radioimmunoassay and an enzyme-linked immunosorbent assay, the antibodies reacted with P-tyr-conjugated target antigens but not with those conjugated with phosphoserine (P-ser) or phosphothreonine (P-thr). This immune reaction was strongly blocked by 2 mM P-tyr and phenylphosphate but not by P-ser or P-thr. The antibodies were capable of isolating, as the major P-tyr-containing components, a 170kd protein (most likely the EGF receptor) from EGF-stimulated, 32P-labelled A431 cells, and 130kd and 60kd proteins from Rous sarcoma virus (RSV)-transformed chick cell lysate which had been labelled in vitro with gamma-32P-ATP. Immunofluorescent staining of RSV-transformed cells and A431 cells showed specific localization of P-tyr-containing proteins in the cytoplasm, plasma membrane, and nucleolus-like structures. The results demonstrated the usefulness of the antibodies for identification or isolation of P-tyr-containing proteins.

Immunofluorescent staining of HeLa cells with rabbit antiserum raised against isolated HeLa cell nucleoli showed bright nucleolar fluorescence. Immunoprecipitation of nuclear extracts obtained from HeLa cells labelled with 35S-methionine or 32P-orthophosphate followed by gel electrophoresis of the precipitate revealed a major band of 90 kd. This antigen, called pp90, was judged to be responsible for the nucleolar fluorescence. Serine residues were predominantly phosphorylated in pp90. Similar nucleolar fluorescence was observed commonly in human cells derived from malignant tumors including acute lymphatic leukemia, adult T-cell leukemia, hepatitis B virus-associated hepatoma, adenocarcinoma, and in 5 lymphoid cells derived from Burkitt lymphoma but not in normal human lymphocytes or liver cells. In immunoprecipitation, 32P-labelled pp90 was commonly detected as the major component in all of those cells which showed nucleolar fluorescence. Resting human embryo lung (HEL) cells were negative for both nucleolar fluorescence and pp90 in immunoprecipitation, but turned positive when stimulated to grow, suggesting the involvement of pp90 in cell growth. Antigen pp90 was also induced in human lymphocytes and HEL cells by infection with Epstein-Barr virus in human cytomegalovirus, respectively, which are known to induce cell DNA synthesis in early stages of infection. A cross-reacting nucleolar antigen was detected in 2 monkey cells but not in 3 rodent cells tested.

There are two classes of proteins that can be phosphorylated on tyrosine in HeLa cells. One class can be detected by metabolic labeling with [32P]Pi and affinity chromatography using anti-phosphotyrosine antibodies. The other cannot be detected by this technique but can be detected among the proteins which bind to the antibodies by in vitro iodination with 125I. Presumably proteins of the second class contain phosphotyrosine at which the phosphate undergoes very slow turnover. The incubation of cells in phosphate-minus medium caused a marked reduction in the levels of phosphotyrosine-containing proteins, this explaining the failure of detection of the second class proteins even after prolonged labeling with [32P]Pi.