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The elucidation of protein–membrane interactions is pivotal for comprehending the mechanisms underlying diverse biological phenomena and membrane-related diseases. In this investigation, vacuum-ultraviolet circular dichroism (VUVCD) spectroscopy, utilizing synchrotron radiation (SR), was employed to dynamically observe membrane interaction processes involving water-soluble proteins at the secondary-structure level. The study utilized a time-resolved (TR) T-shaped microfluidic cell, facilitating the rapid and efficient mixing of protein and membrane solutions. This system was instrumental in acquiring measurements of the time-resolved circular dichroism (TRCD) spectra of β-lactoglobulin (bLG) during its interaction with lysoDMPG micelles. The results indicate that bLG undergoes a β–α conformation change, leading to the formation of the membrane-interacting state (M-state), with structural alterations occurring in more than two steps. Global fitting analysis, employing biexponential functions with all of the TRCD spectral data sets, yielded two distinct rate constants (0.18 ± 0.01 and 0.06 ± 0.003/s) and revealed a unique spectrum corresponding to an intermediate state (I-state). Secondary-structure analysis of bLG in its native (N-, I-, and M-states) highlighted that structural changes from the N- to I-states predominantly occurred in the N- and C-terminal regions, which were prominently exposed to the membrane. Meanwhile, transitions from the I- to M-states extended into the inner barrel regions of bLG. Further examination of the physical properties of α-helical segments, such as effective charge and hydrophobicity, revealed that the N- to I- and I- to M-state transitions, which are ascribed to first- and second-rate constants, respectively, are primarily driven by electrostatic and hydrophobic interactions, respectively. These findings underscore the capability of the TR-VUVCD system as a robust tool for characterizing protein–membrane interactions at the molecular level.

ABSTRACTThe double differential cross-sections (DDXs) of photoneutron production via the photonuclear reaction on tantalum, tungsten, and bismuth for 16.6 MeV linearly polarized photon beam were measured using the time-of-flight method at the NewSUBARU-BL01 facility. Polarized photons were obtained by the laser Compton backscattering (LCS) technique. Two distinct components were observed on the spectra: the low-energy component up to 4 MeV and the high-energy above 4 MeV. The angular distribution of the low-energy component was isotropic, whereas the high-energy was distributed anisotropically and affected by the polarized incident photons. These distributions were similar to the previous studies on the 197Au target. The low-energy component's data were fitted with the Maxwellian function. According to the fitting results, the slopes of low-energy neutrons’ distribution for natTa and natW are similar and steeper than that of 209Bi. The anisotropy of the high-energy component can be expressed as a function of $\cos 2{\rm{\Theta\ }}$cos2Θ , where $\Theta $Θis the angle between the direction of the photon polarization and neutron emission.The DDX energy integrations of the high-energy component were calculated and compared between the three targets. These integration values on natTa and natW were comparable and around 1.5 times smaller than those on 209Bi, regardless of the detection angles.

Cyclic peptides as a therapeutic modality are attracting a lot of attention due to their potential for oral absorption and accessibility to intracellular tough targets. Here, starting with a drug-like hit discovered using an mRNA display library, we describe a chemical optimization that led to the orally available clinical compound known as LUNA18, an 11-mer cyclic peptide inhibitor for the intracellular tough target RAS. The key findings are as follows: (i) two peptide side chains were identified that each increase RAS affinity over 10-fold; (ii) physico-chemical properties (PCP) including Clog Pcan be adjusted by side-chain modification to increase membrane permeability; (iii) restriction of cyclic peptide conformation works effectively to adjust PCP and improve bio-activity; (iv) cellular efficacy was observed in peptides with a permeability of around 0.4 × 10–6cm/s or more in a Caco-2 permeability assay; and (v) while keeping the cyclic peptide’s main-chain conformation, we found one example where the RAS protein structure was changed dramatically through induced-fit to our peptide side chain. This study demonstrates how the chemical optimization of bio-active peptides can be achieved without scaffold hopping, much like the processes for small molecule drug discovery that are guided by Lipinski’s rule of five. Our approach provides a versatile new strategy for generating peptide drugs starting from drug-like hits.

We report a versatile and durable method for synthesizing highly N-alkylated drug-like cyclic peptides. This is the first reported method for synthesizing such peptides in parallel with a high success rate and acceptable purity that does not require optimizations for a particular sequence. We set up each reaction condition by overcoming the following issues: (1) diketopiperazine (DKP) formation, (2) insufficient peptide bond formation due to the steric hindrance of the N-alkylated amino acid, and (3) instability of highly N-alkylated peptides under acidic conditions. Using this newly established method, we successfully synthesized thousands of cyclic peptides to explore the scope of this modality in drug discovery. We here demonstrate the syntheses of a hundred representative examples, including our first clinical N-alkyl-rich cyclic peptide (LUNA18) that inhibits an intracellular tough target (RAS), in 31% total yield and 97% purity on average after 23 or 24 reaction steps.

Defect dynamics during early stages of plastic deformation of copper single crystals are investigated via spectral analysis of acoustic emission (AE) with the aim to clarify the role of a surface in AE. The crystals plated with a thin film of amorphous NiP were examined together with unplated samples of the same [110] tensile orientations, geometry and dimensions. Features of AE are described in terms of statistical treatment of spectral parameters. It is shown that the surface conditions greatly affect AE. AE significantly changes in a time domain from the continuous type in unplated samples to the burst type in plated ones. Substantial changes in the shape of power spectra are also found. The results are interpreted by assuming that the resulting AE is largely due to dislocation escaping from the crystal. Statistical models of individual and collective AE sources are found to be capable of describing most of the AE features.

Evaluation of surface damage layers formed by mechanical grinding processes is indispensable in epi-ready SiC wafer preparation. As well as microstructure, the analysis of local strain distribution in the damage layers gives a clue on control of the wafer quality. Advanced electron backscatter diffraction (EBSD) technique is applied to evaluate the strain distribution of the damage layers. It is revealed that the elastic strain distribution can be classified into a hierarchy of three regions with respect to depth from the surface. Combining EBSD analysis with TEM observation, large compressive elastic strain and misorientation are introduced in the highly-defective region underneath the ground wafer surface. In addition, the gradient distribution of the strain is observed clearly below the highly-defective region. The knowledge of correlating between strain distribution and microstructure is promising to control the damage layer for the wafer preparation.

ABSTRACTWe have proposed a new selective isotope transmutation method using photonuclear reactions with quasi-monochromatic γ-ray beams. This method is based on the fact that the particle threshold of a long-lived fission product (LLFP) such as 93Zr, 107Pd, or 79Se is lower than those of stable isotopes of the same chemical element. Therefore, this method has the excellent advantage that LLFPs cannot, in principle, be produced newly even if the target materials include stable isotopes in addition to LLFPs. Furthermore, this method is effective for 126Sn, 135, 137Cs, 90Sr, and 3H. The nuclear data involved and suitable γ-ray sources are discussed. Laser Compton scattering γ-ray sources and neutron capture γ-rays in nuclear reactors are candidates for this method.

AbstractZygotes are totipotent cells that have the ability to differentiate into all cell types. It is believed that this ability is lost gradually and differentiation occurs along with the progression of preimplantation development. Here, we hypothesized that the loose chromatin structure is involved in the totipotency of one-cell stage embryos and that the change from loose to tight chromatin structure is associated with the loss of totipotency. To address this hypothesis, we investigated the mobility of eGFP-tagged histone H2B (eGFP-H2B), which is an index for the looseness of chromatin, during preimplantation development based on fluorescent recovery after photobleaching (FRAP) analysis. The highest mobility of eGFP-H2B was observed in pronuclei in 1-cell stage embryos and mobility gradually decreased during preimplantation development. The decrease in mobility between the 1- and 2-cell stages depended on DNA synthesis in 2-cell stage embryos. In nuclear transferred embryos, chromatin in the pseudopronuclei loosened to a level comparable to the pronuclei in 1-cell stage embryos. These results indicated that the mobility of eGFP-H2B is negatively correlated with the degree of differentiation of preimplantation embryos. Therefore, we suggest that highly loosened chromatin is involved in totipotency of 1-cell embryos and the loss of looseness is associated with differentiation during preimplantation development.

In fair weather, a clear diurnal variation of atmospheric electric field (AEF), which is distinctly different from the global diurnal variation, i.e., Carnegie curve, was observed during the summer time (July and August) of the year 2010 and 2011 at the summit of Mount Fuji, Japan (3776 m in altitude). The variation of the AEF at the summit showed a local time dependent feature, which means that the AEF increased at sunrise and decreased at sunset. This local diurnal variation is known as a mountain variation. The intensity of AEF in the daytime reached 1.5–3 times larger than that in the nighttime. From the multipoint observations of cloud images and AEF, the mountain variation was found to be attributable to the AEF generated by the positively charged top of a horizontally extensive sea of clouds below the summit. Since the sea of clouds grows with the temperature rise, the AEF variation follows local time. Non‐Carnegie‐curve diurnal variation is observedA local diurnal variation is observed at the summit of high mountainThe variation is attributed to the growth of sea of clouds below the summit

AbstractThere are various demands for air-conditioning in each office space resulting from the variability of thermal distribution caused by a bias of heat sources. Furthermore, individual demands on the thermal environment are diverse. Therefore, it is difficult to satisfy all demands using conventional air-conditioning systems since these assume perfect mixing. Instead, demand may vary with the result that some spaces could be excessively or unnecessarily cooled. This paper examines an airflow and temperature control for personal air-conditioning. This is aimed at providing personal comfort on demand while not unnecessarily cooling unoccupied zones. The method utilizes a multi-flow ceiling cassette type packaged air-conditioner. In this study, thermal comfort and energy performance were analysed using (Computational Fluid Dynamics). From this a personal air control and thermal comfort strategy was developed.

This paper describes an adaptive learning system based on mobile phone email to support the study of Japanese Kanji. In this study, the main emphasis is on using the adaptive learning to resolve one common problem of the mobile-based email or SMS language learning systems. To achieve this goal, the authors main efforts focus on three aspects: sending the contents to a learner following his or her interests, adjusting the difficulty level of the tests to suit the learner’s proficiency level, and adapting the system to his or her learning style. Additionally, this system has already been evaluated by the learners and the results show that most of them benefited from the system and would like to continue using it.

The pure copper single crystals with specific crystallographic orientated were subjected to ECAP for one pass at room temperature. Two types of shear bands were observed. Type 1 shear bands were constructed with clusters of distorting micro shear bands and matrix. Micro shear band and matrix were delineated by large-angle grain boundaries, and these two orientations are in a twinning relationship. Parallel sets of deformation twins were observed in the matrix. Type 2 shear bands had no crystallographic feature, and shear band and matrix were considered as low-angle grain boundaries. Deformation twin was not observed both in matrix and the shear bands.

composite particles were prepared by a gas-solid phase reaction. The precursor particles for the olivine compounds were prepared by an intimate mixing of , , and and by calcination at in a atmosphere. Then, they were heated up to a predetermined temperature under a constant flow of hydrocarbon gas, which is a source of elemental carbon. The adjustment of the temperature enabled us to obtain the composite particles with few magnetic impurities (the spontaneous magnetization was less than 0.01 emu/g) as well as good electrical conductivity (the compact conductivity was higher than ). The composite particles, synthesized under the optimized condition, showed a reversible capacity greater than 150 mAh/g at a low current density of 0.1 C. Simultaneously, they also exhibited a superior performance in both cycle stability and rate capability.

The yields of IO radical from the reaction of CH3I with Cl atom in the presence of O2were determined as functions of total pressure from 5 to 250 Torr of N2diluent and temperature over the range of 278 to 328 K using cavity ring-down spectroscopy. The yields are pressure and temperature dependent. The rate constants and product branching ratios of the reaction of CH2I radical with O2were investigated. We determined a rate constant of (1.28±0.22)×10−12cm3molecule−1s−1at 298 K (2σ uncertainty) for this reaction. Theoretical calculations were performed to determine energetics of the reactions of CH2I + O2and CH2Br + O2. The present results suggest that non-negligible IO radicals will be formed from the reactions of CH3I/CH2I2+ OH/Cl/NO3at atmospheric conditions.

In this study, susceptibility to SCC of nanostructured Cu-10wt%Zn alloys, produced by equal-channel angular pressing (ECAP) was investigated under the constant stress test in ammonia vapour, which has been well-known typical environment for IGSCC of Cu-Zn alloy. Billets having diameter of 20 mm and length of 100 mm were subjected to ECAP for eight passes at room temperature to obtain structure with grain size of about 100 nm. After ECAP, some of the billets were flush-annealed in 473 K for 60 seconds to decrease excessive unequilibrium dislocations at grain boundaries. Coarse grained specimens without ECAP and one-pass specimens were also tested for comparison. The specimens for SCC were tensioned by a constant load in ammonia vapour inside a glass chamber for 24 hours at room temperature. After the SCC tests, maximum length of cracks was evaluated by SEM. Specimen having UFG structure by 8-passes exhibited cracks in lower applied stress ratio, (=σa/σys) compared with 0- and 1-pass samples, where σa is applied stress and σys is yield stress, respectively. Most importantly, the specimen with annealed at 473K for 60s after ECAP cracked in higher applied stress. It became less sensitive to SCC after flush annealing although mechanical properties were not changed considerably. In our previous studies, we reported that the SCC of UFG copper produced by ECAP, and the sensitivity to SCC becomes lower by flush annealing. Results are discussed in terms of grain boundary state with or without extrinsic grain boundary dislocations

The role of the deformation pre-history in high-cycle fatigue properties of copper produced by severe plastic deformation is discussed. The focus is placed on comparison of the structures and mechanical behaviours of two types specimens produced either by rolling or by ECAP, i.e. by the pure shear or simple shear mode, respectively. It is shown that the deformation either by simple or pure shear mode to the same equivalent strain results in alike mechanical properties, both monotonic and cyclic. The significant influence of the initial stages of strain hardening on fatigue is highlighted.

This paper describes the influence of initial crystallographic orientation on the formation of dense shear bands in pure copper single crystals subjected to equal-channel angular pressing (ECAP) for one pass at room temperature. Local orientation change during simple shear by ECAP traced by electron backscatter diffraction (EBSD) indicated that the shear bands were formed when twinning plane and direction become parallel to the macroscopic shear plane and shear direction of simple shear strain, respectively. Orientation splitting associated with shear bands have a twinning relation. The shear bands were delineated by large-angle grain boundaries, having close relation to twinning relation with matrix, suggesting the role of deformation twinning as their nucleation sites. The activation of deformation twinning is suggested and can be rationalized by favorable crystallographic orientation and critical dislocation density as indicated elsewhere by the present authors.

Sliding wear and hardness tests in Ni/Cu multilayers electrodeposited on polycrystalline copper substrate were carried out. The multilayers had a total thickness of 5 μm and an individual layer thickness from 5 to 100 nm. Hardness of the multilayers measured with a nanoindentation tester was found to be dependent on layer thickness. The multilayer with the layer thickness of 20 nm showed the highest value among them. It was found that the wear resistances of all the multilayers tested were higher than that of an electrodeposited nickel coating. It was also revealed that the specific wear rate of multilayers decreased with decreasing the layer thickness although the highest hardness was attained at the 20 nm layer thickness. Scanning ion microscope observation showed that the subsurface area kept the layered structure of nickel and copper even after sliding wear. The multilayer had plasticity sufficient to accommodate deformation coming from the sliding wear, because fine grains peculiar to severe plastic deformation process were formed near the worm surface.

Co/Cu and Ni/Cu multilayers fabricated by electroplating technique were annealed at various temperatures in order to investigate thermal stability of multilayered structures. Vickers hardness tests on the annealed Co/Cu and Ni/Cu multilayers were conducted at room temperature. It was recognized that after the annealing at 1023K the Co/Cu multilayer still maintained the hardness of as-deposited state. On the other hand, the hardness of Ni/Cu multilayer was almost identical to copper substrate after the annealing at 903K.

A sliding wear test was conducted in a copper single crystal having (001) surface. Microstructures induced by the sliding wear were investigated by means of the electron channelling contrast (ECC) imaging and electron backscattered diffraction (EBSD) analysis. The microstructures below the worn surface consisted of the stack of dislocation cell structure, layered structure and equiaxed fine-grained structure. At the dislocation cell structure, there was no significant change in crystallographic orientation. On the other hand, the crystal at the layered structure rotated continuously around the axis which was perpendicular to sliding wear direction. In the fine-grained structure, preferential orientations no longer existed. The authors attempted to explain grain boundary formation in terms of a rotation angle gradient which is proportional to density of geometrically-necessary dislocations.

Effect of Ni/Cu multilayer coating on fatigue durability was investigated. The Ni/Cu multilayered films were coated on cylindrical copper specimens by electroplating technique. Thickness of individual component layers was h=20nm and 100nm and the total thickness was 5μm. The specimens with a conventional nickel coating and uncoated specimens were also prepared. Push-pull fatigue tests were carried out in air at room temperature. It was found that the specimens with the Ni/Cu multilayered coatings exhibited the fatigue lives longer than those of the conventional nickel coating. In particular, the fatigue life with the h=100nm multilayer was at least ten times longer than that with the nickel coating at the stress amplitude of 90MPa. From the electron channelling contrast imaging (ECCI) observation of subsurface areas of the copper specimens, dislocation structures peculiar to fatigue deformation was suppressed by the surface coatings.

Corrosion of ultra-fine grain (UFG) copper fabricated by equal-channel angular pressing (ECAP) has been investigated in comparison with that of recrystallized coarse grain (CG) copper. Corrosion current was estimated by a Tafel extrapolation method to examine the kinetics of corrosion in a modified Livingstone etchant, which attack dislocations and grain boundaries preferentially. UFG copper have exhibited a lower corrosion current in comparison with that in its recrystallized coarse grain (CG) counterpart despite the fact that the dislocation density and total fraction of grain boundaries are much greater in UFG copper than in CG copper. Corrosion damage on its surface is macroscopically rather uniform whereas obvious attack at grain boundaries and selective corrosion of some grain interiors were observed in CG copper.

Microstructures of Ni/Cu and Ni-Co/Cu multilayers were investigated by X-ray diffraction analysis. These multilayered structures were fabricated on copper substrates using electrodeposition technique. At an as-deposited Ni/Cu multilayer with the layer thickness of h=5nm, a single diffraction peak appeared, although the multilayer of h=100nm exhibited the diffractions splitting into two peaks which resulted from both the Ni and Cu layers. In the Ni-Co/Cu multilayers, it was found that composition of the Ni-Co layer depended on an electric potential applied during deposition. The fcc and hcp structures were detected at the Ni-rich and the Co-rich deposits, respectively. The Vickers hardness of the Co-Ni/Cu multilayer was higher than that of the Ni/Cu multilayer.

A fatigue crack growth test was conducted in a polycrystalline copper. Dislocation structure formed near an intergranular fatigue crack was investigated by electron channelling contrast imaging (ECCI) method. The ECCI method enables us to observe dislocations lying under surface using a scanning electron microscope. The fatigue crack in the copper specimen was grown along both grain boundaries and slip bands inside grain. The ECCI observations revealed that both the vein dislocation structure and the cell structures were formed near the grain boundaries. The formations of different dislocation structures near boundaries could be interpreted in terms of the plastic strain incompatibility.

Strengths of multilayered structures have been investigated using three-dimensional discrete dislocation dynamics (DDD) simulation. The multilayered structure was modeled as a stack of misfit dislocation networks which must exist at an interface between adjoining crystals having different lattice constants. Passages of a single mobile dislocation through several kinds of network stacks were simulated. The critical stress required for the dislocation passage depended on the dislocation spacing of the network, the number of network sheet and the spacing between network sheets.

The fatigue properties of ferritic stainless steel containing deformation twins were investigated. Monotonic tensile tests and push-pull fatigue tests were conducted on the specimens both with and without twins. Fatigue lives of the twinned specimens were about four times shorter than those without the deformation twins, although yield stresses of both specimens were almost equal. It was found that the fatigue cracking along the deformation twin boundaries caused the reduction in fatigue life. Dislocation structure observation using the ECCI method revealed that no specific dislocation structure was formed near the cracked deformation twin boundary, although the ladder-like PSB structure was developed along an annealing twin boundary in an austenitic stainless steel.

The present work is aimed at linking the microstuctutral features obtained after severe plastic deformation via ECAP to the tensile behavior and thermal stability of pure (99.98%) copper processed by routes A and Bc to different number of passes. The main conclusion one can draw unambiguously from the currently available results is that the strain path exerts relatively little effect on the resultant tensile properties when the number of pressing is sufficiently large, although there have been some marked differences in crystallographic textures and distribution of grain-boundaries. The effect of the number of pressings on the tensile ductility is considerable.

Strengthening is a complex process involving such basic mechanisms as dislocation accumulation (work hardening), Hall-Petch hardening due to grain refinement, solid solution hardening and precipitation hardening in various combinations. The contribution of different mechanisms into resultant strength can vary significantly depending on chemical composition and processing. The purpose of the present work is to explore the significance of SPD for hardening and to clarify the role of different strengthening mechanisms. The model Au-based system was employed using pure Au, single phase solid solution Au-25Ag and precipitation hardenable Au-12.5Ag-12.5Cu (in mass %) alloy subjected to ECAP. The additive character of different strengthening mechanisms is clearly demonstrated. The extremely high strength exceeding 1 GPa is achieved in the Au-Ag-Cu after ECAP followed by aging, which has never been attained in conventional processing schemes.

Copper single crystals were subjected to equal-channel angular pressing (ECAP) via the so-called route A and Bc, in order to examine the influence of initial crystallographic orientation and processing route on microstructure development and grain fragmentation. Microstructural changes were examined by transmission electron microscopy (TEM). The pressing via the route Bc resulted in finer microstructure for all orientations in terms of grain size, equiaxiality and orientation scattering after four passes. Effect of initial crystallographic orientation on the grain refinement was also recognized, and it might be attributed to heterogeneous deformation such as shear bands, whose formation is strongly orientation dependent. After eight passes, however, the effect of processing route and initial orientation cannot be recognized.

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Buffer-gas pressure broadening for the 3 001III← 0 0 0 band of CO2in the 1600 nm region was investigated with continuous wave cavity ring-down spectroscopy within the temperature range 263–326 K. The measured absorption profiles were analyzed with Voigt functions. Pressure broadening coefficient, γgas, and the temperature dependent parameter broadening exponent, n, were determined for a variety of buffer gases: N2, O2, He, Ne, Ar, Kr and Xe. γair values estimated subsequently are 0.0962 for R0, 0.0855 for P8, 0.0752 for P16, 0.0704 for P26, and 0.0692 for P38 in units of cm−1atm−1, where numbers in parentheses are one standard deviation in units of the last digits quoted. nair values are 0.774 for R0, and 0.7311 for P8.

Our purpose was to investigate whether the local or systemic factors of pregnancy are associated with inducible nitric oxide synthase (iNOS) mRNA expression and to determine the inhibitory effects of pharmacological agents that increase cGMP levels in rat myometrium. iNOS mRNA expression was determined in uterine tissues from nonpregnant rats and on day 17 of gestation in the pregnant and non-pregnant uterine horns by RT-PCR. In addition, uterine rings from the pregnant and non-pregnant uterine horns were placed in Krebs-Henseleit solution for isometric recordings of spontaneous contractions. Concentration-inhibition relationships to diethylamine/nitric oxide complex, 8-bromo-cGMP, and the selective phosphodiesterase V inhibitor were obtained. Compared to nonpregnant rats, expression of iNOS mRNA in myometrium increased during pregnancy, which was maximal on day 17, followed by a decrease on day 21 of gestation. Expression of iNOS mRNA at day 17 of gestation was greater in pregnant uterine horns than in nonpregnant ones. Maximal inhibition of phosphodiesterase V and increasing cGMP induced similar inhibition of spontaneous contractions in nonpregnant and pregnant uterine horns, while NO induced less inhibition in the former. The results suggest that the local pregnancy factor is needed for signal transduction from NO to soluble guanylate cyclase at a time when maximal expression of iNOS mRNA is evident.

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Alteration of Ti 2p XPS spectra for TiO2single crystal was measured during Ar ion sputtering. The acceleration voltage of Ar ion bombardment ranged from 10 V to 2 kV.

Alteration of Ti 2p XPS spectra for TiO2 single crystal was measured during Ar ion sputtering. The acceleration voltage of Ar ion bombardment ranged from 10 V to 2 kV. Components of Ti²⁺ and Ti³⁺ as reduced states have appeared, in addition to the Ti⁴⁺ state, after ion bombardment at 2 kV. However, although a small amount of Ti³⁺ has been observed in the case of 10 V bombardment, the Ti²⁺ component has not appeared. The intensities of the reduced states (Ti²⁺ and/or Ti³⁺) that have appeared at each acceleration voltage reach constant values after a long sputtering time. This saturation shows that the surface reaches an equilibrium state between the sputtered atoms and implanted ions. Moreover, the intensities of the reduced states increase with increasing accelerating voltage of the primary ions. The alteration by 10 V ion bombardment suggests that there is a critical energy for reduction to the Ti²⁺ state. Copyright © 2002 John Wiley & Sons, Ltd.

Two optical methods, cavity ring-down spectroscopy and photoacoustic spectroscopy, are applied to the measurement of the isotope ratio ^18O/^16O in water-vapor samples with a Nd^3+:YAG pumped-dye laser. The combination band of (2ν_1 + ν_3) in the 960-nm region of water molecules is investigated for two standard water samples, the Vienna Standard Mean Ocean Water and the Standard Light Antarctic Precipitation. The results demonstrate that the two methods have the potential of compact systems for in-situ measurements of H_2O isotope ratio in the environment.

Two optical methods, cavity ring-down spectroscopy and photoacoustic spectroscopy, are applied to the measurement of the isotope ratio ^18O/^16O in water-vapor samples with a Nd^3+:YAG pumped-dye laser. The combination band of (2ν_1 + ν_3) in the 960-nm region of water molecules is investigated for two standard water samples, the Vienna Standard Mean Ocean Water and the Standard Light Antarctic Precipitation. The results demonstrate that the two methods have the potential of compact systems for in-situ measurements of H_2O isotope ratio in the environment.

The paper presents a study of the effects of initial fabric and shearing direction on cyclic deformation characteristics such as stress-strain response, shear modulus and damping ratio from drained static cyclic tests on medium dense Toyoura sand using hollow cylinder apparatus. The apparatus allows independent control of stress components, σz, σθ, σrand τzθ, and accurate measurement of strain components, εz, εθ, εrand γzθ, over a wide range of strains from 10-3% to 10%. Three methods of sample preparation, air pluviation, water pluviation and dry rodding, were employed to produce different initial fabrics. Samples were sheared cyclically in p’-constant plane along the direction of major principal stress 0° (90°), 22.5° (–67.5°) and 45° (–45°) relative to the direction of deposition. Anisotropic behaviour was observed in stress-strain response and the secant shear moduli defined separately for each direction of major principal stress. However, the equivalent shear modulus was found to be little affected by the direction of the major principal stress. In addition, the effect of initial fabrics was not significant. The same was found for the hysteretic damping ratio.