The Beckmann rearrangement of aliphatic ketone oximes, R(CHs)=NOH (R=Et (1); n-Pr (2); iso-Pr (3); iso-Bu ()), with polyphosphoric acid (PPA), polyphosphate ester (PPE), and ester of phosphoric acid (2 P- R) was carried out and migratory ratios ((a)/(b) in eq. (1)) were determined, The results are shown in Fig.1, 2, and 3, respectively.
In Fig.1 and 2, the migratory ratios decrease with reaction time and nearly approach to the ratios of anti-alkyl form/syn-alkylform in benzene(A1) or DMSO(A2)except for (3) (See Table 1). From this fact, it has been found that PPA and PPE are inactive for isomerization of the oximes andanti-alkyl oximes rearrange faster than syn-alkyl ones. ln the case of (3), migratery ratios are smaller than Ai or A2. As acetonitrile is detected by GLC, it is presumed that fission has been occurred simultaneously with rearrangement in anti-alkyl oxime (eq. (3)). In the case of 2 P- R, all modes of the reaction arethe same as in above, except that the rate of fission is tnuch faster than that in PPA and PPE.
The reaction of anti-alkyl ketone oximes having a bulky grouphas been greatly influenced by the use of sterically demanding catalysts such asPPA, PPE, and 2 P- R.

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By employing an undrained cyclic loading ring-shear apparatus, a series of tests to reproduce the dynamic behavior of the Nikawa landslide induced by the January 17, 1995 Hyogoken-Nambu earthquake, is conducted. The test sample is Osaka-group coarse sandy soil taken from the landslide. The initial stress condition acting on a soil element in the sliding surface is applied to the sample. Based on the seismic records monitored at the JR Takarazuka Station, the input seismic wave is synthesized to reproduce the seismic stress acting on the sliding surface. The test results show that the soil failed due to the dynamic loading of the earthquake. The most important results are the excess pore water pressure generation and the acceleration of shear displacement continuing after the main shock. Combined with the grain crushing at the shear zone and the volume reduction in the drained constant-speed ring-shear test, the mechanism of this landslide is interpreted as, shear displacement causing grain crushing in the shear zone and volume reduction, and then resulting in a localized liquefaction phenomenon, "sliding-surface liquefaction". This geotechnical simulation test provides a reasonable interpretation of this highly mobile landslide.

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An empirical equation in use for estimating the pseudo-elastic shear modulus, G_f, of subsoil, associated with shear strains less than 0.001% is proposed in this paper. In a series of in-situ seismic cone tests performed nationwide, the profiles of both G_f and the in-situ void ratio, , with depth were successfully characterised at five sites, each comprising a soft clay layer deposited in the Holocene era. The database which comprised the original data from the field and laboratory tests, coupled with similar information on well-documented Holocene clay deposits in Europe, was statistically analyzed in attempts to determine a generalised relationship with which G_f of soft clay may be reasonably estimated only from routinely available borehole data; that is and the current geostatic effective overburden pressure, σ'_v. An empirical relationship, G_f=, 000 -√(σ'_v) (kPa), was derived from the statistical analysis applied to data from seven different clays worldwide, for which extended over a range between 1 and , and the overconsolidation ratio ranged roughly between 1 and 2. The applicability of the proposed relationship was evaluated for two case records, each in which the clay exhibited unusual behavior; i.., the undrained shear strength remained more or less constant with depth due to the existence of artesian pressure at one site, and, at the other, G_f decreased, whereas increased, with depth. It was demonstrated that even in these clay deposits exhibiting exceptional profiles, the proposed relationship was capable of predicting G_f with a reasonable accuracy by determining the profiles of and σ'_v with depth. In addition, the prediction when compared to G_max from carefully performed laboratory cyclic tests, yielded a better estimate of G_f from the in-situ seismic survey. Despite the fact that the empirical relationship was initially designated to estimate G_f of soft clays, it may be equally applicable to sandy deposits. This was verified by comparing it to similar, and well-established, relationships developed for sands. A case record as such is also described for a loose sand deposit at Higashi-Ohgishima in Tokyo Bay which was placed in 1960's by land reclamation.

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In this paper, consideration is given as to how to characterize depth-variation for the small-strain shear modulus of natural clay sedimentation, in a state of normal consolidation. A case study was carried out for a relatively uniform clay layer deposited in the Holocene era. Initially, the effects of both strain and in-situ stress levels on secant shear modulus were carefully examined in cyclic torsion shear tests using undisturbed samples, which were recovered at different depths in a test borehole. The range of shear strain examined was between 0.001% and 1%. Similar examination was made for a silty clay using reconstituted samples that were isotropically consolidated at different stress levels. On the basis of the results of these laboratory tests, together with the shear modulus from an in-situ seismic survey, the small-strain shear modulus was formulated in terms of the stress and strain levels, and linked also to undrained shear strength. Interactions of the small strain stiffness between in-situ and laboratory are discussed in depth with an attention paid to the existing aging effect in the original subsurface condition.

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The modulns of longitudinal elasticity and their temperature dependence in commercial aluminum cast alloys were measured in the temperature range from room temperature (20°) to 250° by the resonant frequency method. The results obtained are as follows:
The modulus of longitudinal elasticity tended to decrease weakly and linearly (the tangent of its decrease, m = (-2.--3.3) × 10²kg/cm²/°) with the rise of temperature. Within the range of the experiments, aluminum cast alloys were divided into 3 groups, the lst group materials having large moduli of elasticity at room temperature (i. ., = (7.15-7.25) × 10⁵kg/cm²) were 2A-T, 3A-F, A-F, A-T, B-F, B-T, A-F, A-T, etc., the 2nd group materials having intermediate moduli (i. ., = (.85-.98) × 10⁵kg/cm²) were -F, -T, -T, -F, -T, 7A-F, etc. and the 3rd group materials showing considerably smaller moduli (i. ., = (.58-.65) × 10⁵kg/cm²) were 1A-F, 1A-T, 2A-F, etc. However, there were some differences between the moduli in this experiments and the moduli in the other data books, and these were considered due to the difference of the measurement principles and of hypotheses or assumptions involved in these principles, so it is suggested that the moduli of elasticity should be reported with indication of the measuring method.

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The rate dependent nature of liquefied sand was investigated by laboratory shear tests. Since previous experience has revealed the many difficulties inherent in maintaining the state of liquefaction of a sandy specimen, new measures were attempted. The test results indicate that the measured shear stress consists of frictional and rate dependent components, and a viscosity coefficient was assessed from the latter component. The measured viscosity varies with the rate of strain as well as the magnitude of strain itself. A similar test on a dry specimen revealed less viscosity and implied that a major part of rate dependency comes from the behavior of pore liquid in the case of water-saturated sand. It was interesting, moreover, that sand with fines was of less viscosity. Finally, a numerical analysis was conducted on a real liquefaction-induced ground deformation and the results were consistent with the observation.

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In view of the significant role of the water film effect in flow failure for a liquefied sandy deposit, the mechanism of water film generation is numerically studied based on a 1-dimensional model test. The process of water film growth and decay can be simulated to a certain extent by a simple consolidation analysis, which indicates that only a small difference in permeability in layered sand is enough for a water film to develop. A 1 G shaking table test for a two-dimensional slope model with an arc of silt within a saturated sand is then addressed to discuss the dilatancy effect exerted in sheared sand during flow failure. It is possible that, once the water film is formed, the transmission of shear stress through it is interrupted, leaving the sand below free from the dilatancy ; this eventually allows the water film to stay without being absorbed during flow failure. The result of another shaking table test for a trapezoidal slope with horizontal silt seams indicate that water films beneath the seams enable the soil mass above them to laterally flow along water films very gently inclined even after shaking. If a silt seam breaks due to excessive pressure in the water film, it triggers re-liquefaction in the upper sand and leads to further instability.

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Thermal, dielectric, X-ray and optical investigations of were carried out above room temperature. It was found that undergoes an improper ferroelastic phase transition at 388°, and has spontaneous strain a_s=(-)/2 = 1. × 10^-2 at room temperature. shows domain structures composed of three kinds of orientations with two types of domain boundaries. The crystal belongs to the space group P6₃/mmc with the hexagonal unit cell parameters of a_h=.295() Å and c_h=.189() Å at 410° . It was deduced that the improper ferroelastic phase transition is characterized by the symmetry change from P6₃/mmc to Pnam.

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  A simple and rapid capillary gas chromatographic (CGC) method with flame ionization detection has been newly developed for analysis of the essential oil from Radix Bupleuri. Twenty components were identified with gas chromatography-mass spectrometry. -2-heptenal, furan, 2-pentyl, and -2-nonenal were quantified simultaneously using the internal standard method. Decane was used as an internal standard. Separation and quantification were achieved on a DB- capillary column (30 m×0.25 mm i. ., 0.25-μm film thickness). The oven temperature was programmed as follows: 60° to 70° at 1°/min rate, 70° for 10 min, 3°/min to 120°, 20°/min to 250°, and held at 250° for min. The oven pressure was programmed as follows: 46.1 kPa for 25 min, 20.0 kPa/min to 77. kPa, and then held for min. Split injection was conducted with a split ratio of 10:1; flow-rate, 1.00 ml/min; carrier gas, nitrogen; injector temperature, 280°; and detector temperature, 280°. The system proved effective in resolving -2-heptenal, furan, 2-pentyl, and -2-nonenal peaks from their interfering components. The method displayed excellent linearity in the range of 26.—1072 μg/ml (-2-heptenal), .—1292 μg/ml (furan, 2-pentyl), and 7.—1564 μg/ml (-2-nonenal). The average recovery rates of -2-heptenal, furan, 2-pentyl, and -2-nonenal were 100.3%, 102.%, and %, respectively. CGC is a quick and accurate method for analysis of the essential oil from Radix Bupleuri.

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Agaricus blazei is an important fungus for producing bioactive compounds. There are some reports of polysaccharides and steroid derivatives from the fruiting bodies of A. blazei. However, the chemical examination of the secondary metabolites of the cultured mycelia of this species has not been reported. Eight compounds, an unprecedented skeleton have been isolated from the cultured mycelia of A. blazei. The structures of the novel compounds each named blazeispirols A (1), B (2), (3), (), () X(), Y (7) and Z () were confirmed by extensive 1 and 2 NMR spectral data and X-ray analysis. Blazeispirols A (1), B (2), (3), () and () were des-A-ergostane type compounds having spiroacetal structure as a side chain. Blazeispirols X () and Y (7) were determined to be (20S, S, 23R, 24S)-1 (10→) abeo-14β, :, 25-diepoxyergosta-,7,,11-tetraene-3α,23-diol and (20S, S, 23R, 24S)-14β,:,25-diepoxy-,23-dihydroxyergosta-,7,11-triene-3,-dione by comparison of extensive 1 and 2 NMR spectral data with that of blazeispirol A. The biosynthesis of blazeispirol A was investigated by feeding ^<13>-labeled acetates and methionine to the growing cultures of A. blazei. The labeling patterns of 1 derived from singly and doubly ^<13>-labeled acetates were consistent with that of ergosterol reported previously except for the A-ring and then ^<14>-labeled ergosterol was incorporated into blazeispirol A. Taking the structures of blazeispirols Z and into consideration, it can be assumed that blazeispirol A is biosynthesized from ergosterol by the cleavage of -, - and -1, -10 bonds on retro aldol condensation and Michael reaction via such as intermediate A as shown in Fig. . A large number of ergostane-type steroids have been isolated from many fungi. However, blazeispirol A is the first example of a naturally occurring des-A-ergostane-type steroid including a spiroacetal structure moiety as a side chain.

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(³H) Tobramycin was used as a probe to determine the relationship between the structure of aminoglycoside antibiotics and their ability to remove this drug from its higher affinity binding site on the ribosome. The dissacharide moieties (neamine, tobramine, gentamine) appeared to have a common binding site, whereas the kanosamine, garosamine and ribose moieties determined the specificity of this binding. Amikacin and butikacin behaved in an anomalous manner in spite of their close structural relationship to tobramycin.

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In this paper, constitutive relations for expressing the inelastic behavior of sandy ground expected at the time of a strong earthquake are proposed. These constitutive relations are formulated by a yield function in terms of effective stress ratio and by a plastic potential function which is derived from the stress ratio-plastic strain incremental ratio defined as a function of accumulated volumetric strain. These constitutive relations employ Sekiguchi and Ohta's stress parameter to take account of the effects of rotation of principal stress axis on the deformation characteristics of sand. The Masing rule is modified in such a way that it can be used in the multi-dimensional stress field, and employed in the hardening function in order to express a hysteretic damping. Material constants contained in the proposed constitutive relations can be easily determined by the mechanical tests which are normally conducted in laboratory. The comparison between predicted behaviors by the constitutive relations and results of undrained cyclic shear tests shows that the dynamic strength-deformation characteristics of sand in a wide range of density can be simulated satisfactorily.

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Two new steroid derivatives, (, 24R)-3α-ureido-ergosta-, , (14), -tetraene (1) and (, 24R)-, -epidioxyergosta-, , -triene-3β-ol 3-O-β--glucopyranoside (2) were isolated from the fruit bodies of Chlorophyllum molybdites (Agaricaceae). The structures were established by spectroscopic and chemical methods. These compounds exhibited cytotoxicity against Kato III cells.

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The behavior of the soft clay grounds subjected to repeated loading is different from that subjected to sustained loading. The difference in settlement between these two loading patterns should be due to secondary compression over a long period of time. Consequently, soft clay grounds subjected to repeated loading tend to be more compressible than those subjected to sustained loading. Therefore, it is necessary for engineers to predict post-construction settlements under repeated loading. In this respect, the preloading is considered to be promising as a countermeasure to reduce the settlement of clay under repeated loading as well as under sustained loading. The effect of preloading on post-construction consolidation settlement of soft clay subjected to repeated loading after removal of a part of preload is investigated in the present paper. It has become clear that the settlement of a clay sample after preconsolidation is mainly affected by the amount of preload, the degree of consolidation due to the preload, the amount of permanent load and the amount of repeated load after removal of preload. The calculated settlement versus time relations using a method to estimate the amount of consolidation settlement of soft clay grounds subjected to repeated loading after removal of preloading were compared with the observed degree of consolidation as parameters of the intensities of preload and repeated load.

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Chemical synthesis of (, 24R)- and (, 24S)-1, 24-dihydroxy--vitamin has been achieved starting with the commercially available dinorcholenic acid acetate. Synthesis involved introduction of the 1-hydroxy group by a reduction of the 1, 2-epoxide generated by epoxidation of the 1, , -trien-3-one. The side chain on the steroid was then constructed by means of a Wittig reaction followed by introduction of the Δ⁷ bond by standard methods and its protection with 1-phenyl-1, 2, -triazoline-3, -dione. Subsequent reduction of the hydroxy groups in the steroid side chain followed by reduction of the Diels-Alder addition products yielded the both 24-isomers. The , 7-dienes were irradiated and the corresponding vitamin compounds isolated. Nuclear magnetic resonance was used to identify individual isomers. The (, 24S)-1, 24-hydroxyvitamin compound bound equally well to the chick intestinal cytosol receptor as 1, 25-dihydroxyvitamin , while the 24R-isomer was approximately ten times less active. In vivo, both isomers were less active than 1, 25-dihydroxyvitamin ; however, the 24S-isomer was considerably more active than the 24R-isomer approaching the activity of 1, 25-dihydroxyvitamin .

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We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MC3T3-1. Sixteen phosphate buffered saline (PBS), boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MC3T3-1 cell differentiation. The enzyme activities were markedly induced by extracts of Tricholoma auratum, and we isolated the active compound from methanol extracts of this mushroom. Physical data for the isolated active compound were identical to those for (,24R)-ergosta-7,-diene-3β,,-triol (1). 1 induced ALP activities of MC3T3-1 cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MC3T3-1 cells by 1, ergosterol (2), ergocalciferol (3), cholesta-3β,,-triol (), 7-dehydrocholesterol () and cholecalciferol () were tested. The enzyme activities of MC3T3-1 cells were increased 3.0-fold by 10 μM 1 and 2.-fold by 10 μM . However, 2, 3, and did not induce MC3T3-1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at - and/or - of 1 and played an important role in their differentiation-inducing activities on MC3T3-1 cells. Furthermore, 1 suppressed induction of MC3T3-1 cell apoptosis by serum starvation.

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