One method currently being considered for the disposal of high level radio-active waste is burial in the seabed. When a hot object is buried in soil, the temperature of the soil adjacent to the object is raised and there is transient heat flow away from the object. The rise in the temperature of the soil causes excess pore pressures to be generated and transient pore water diffusion also takes place. A finite element formulation of the coupled heat flow and consolidation problem is presented. The computer implementation of this formulation is found to compare favourably with analytical solutions based on the same physical principles.

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Stereoselective synthesis of , - and , Z-β-ionylideneacetaldehydes was accomplished from the β-ionone tricarbonyl iron complex, and the latter was converted to Z-retinoic acid.

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Stress wave theory is applied to open-ended pipe piles to clarify the effects of soil plug on the behaviour of piles during driving and static loading. Measured field data and various numerical models are reviewed ; methods are presented to calculate wave propagation in both the pile and the soil plug ; modelling is presented which takes into account the interaction between the soil plug and the pile ; also presented is simplified method to estimate the loadsettlement relation of the pipe pile in static loading. By correlating observed and calculated values in two analytical cases, the authors demonstrate that incorporation of the soil plug (modelled as a series of masses and springs) is required to correctly predict pile behaviour during driving and static loading.

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Two new partially saturated tricyclic ring systems, 6, 6a, , , , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (3a and 3), and -thiepins (a and ) were synthesized. Compounds a and were desulfurized to give a pair of isomeric 2-methylbenzoylcyclohexanes (10a and 10). Deuterated a and (11a and 11) were prepared starting from butadiene-d₆ (12). The stereochemical features of 3a (trans), 3 (cis), a (trans) and (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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From the fronds of Polystichum tripteron (KUNZE) P_R. a new norcarotenoid glycoside was isolated and shown to be (6R, , R)--hydroxy-megastigma-, -dien-3-one--O-β-D-glucoside. The fronds of Dennstaedtia wilfordii (MOORE) CHRIST. contain the same glucoside.

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11-Amino-6, 6a, , , , 10, 10a, 11-octahydrodibebenzo[, ]thiepines (6a-d) and -oxepines (a-d) were synthesized by the Leuckart reaction of 6, 6a, , , , 10, 10a, 11-octahydro-11-oxodibenzo[, ]thiepines (1a, )and -oxepines (2a, ) followed by hydrolysis of the reaction products a-d and 5a-d, respectively. The four diastereomers, cis(6a-H, 10a-H)-cis(10a-H, 11-H) 6a and a, cis(6a-H, 10a-H)-trans(10a-H, 11-H) 6 and , trans(6a-H, 10a-H)-trans(10a-H, 11a-H)6c and c, and trans(6a-H, 10a-H)-cis(10a-H, 11-H) 6d and d, were isolated and their configurations and conformations were elucidated by chemical methods together with ¹H-nuclear magnetic resonance spectroscopic and X-ray crystallographic analyses.

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The ability of Climacodon septentrionalis to immobilize and kill a mycophagous nematode (Aphelenchoides sp.) in vitro is described for the first time. Two isolates produced droplets (20–45 μm in diameter) that formed at the apices of tall, stalked, and branching secretory cells (700–1,500 μm tall). On 2% modified malt extract agar, nematodes became enveloped in the droplets, which restricted their ability to move and resulted in complete immobilization and death within several hours of contact. The rate of decomposition of the nematodes varied considerably, with most individuals persisting for weeks whereas others were degraded within several days and appeared to be colonized by dense hyphal growth. This study provides the first documentation of a non-agaricoid fungus producing secretory cells that are able to immobilize nematodes.

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The mechanism of wave-induced instability in a permeable seabed have been studied for more than two decades. The distinction between shear failure and liquefaction, however, has not been clearly defined. This paper presents a fundamental study on the differences in two failure modes for a fully saturated seabed of both finite and infinite thickness. The wave-induced effective stresses and pore pressure, obtained from an analytical solution of Biot's pore-elastic consolidation theory, were employed to examine the failure modes under a two-dimensional plane strain condition. A case study is presented to examine the failure modes with respect to several parameters, such as excess pore pressure, seepage flow, seepage force, failure areas and stress path in the seabed. The conclusions obtained from this study were as follows ; (1) the thickness of a permeable seabed affects the pore pressure and effective stress response to ocean waves and the failure mode of the seabed, (2) either a liquefaction or shear failure, or both, occur in the seabed, even in the saturated seabed, (3) the Mohr-Coulomb's failure criterion, when combined with elastic stresses, can not be employed to estimate the liquefaction failure in the seabed, () the liquefaction can be evaluated by a criterion in terms of the excess pore pressure, (5) The liquefied zone in the seabed is significantly different from the shear failure zone. The shape beneath the seabed surface for the former is almost identical to the contour where the upward seepage flow is concentrated.

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In the 1993 Kushiro-oki Earthquake of Richter magnitude ., simultaneous recording of earthquake motions was successfully made at the ground surface and at a depth of 77 meters in a dense saturated sand deposit. The peak horizontal acceleration was 0.47 g on the ground surface and 0.21 g at a depth of 77 meters. The acceleration record at the ground surface showed a distinctive ground response, which consisted of a cyclic motion having a period of about 1.5 seconds overlain by a spike at each peak of the motion. In order to study the mechanism of this peculiar ground response, effective stress analysis was conducted on the dense saturated sand deposit. The model used for this study was a strain space multiple mechanism model, which takes into account the effect of principal stress axis rotation. The recorded earthquake motion at a depth of 77 meters was used as the input earthquake motion for the analysis. Sampling after in-situ freezing was done in order to evaluate the properties of the sand. The results of the analysis indicated that the observed ground response was due to the effect of dilatancy of sand, which plays a significant role in the response of the dense saturated sand deposits during strong earthquake motions.

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In this paper, centrifuge shaking table tests were conducted in order to understand the performance of seawalls during a seismic event. The model tests showed that the displacement of the caisson was much affected by the seaward shear deformation of the sand seabed beneath it during shaking. It was also confirmed that an armored embankment played an important role in the displacement of the caisson during shaking. Based on these test results, a two-dimensional DEM-FEM coupled analysis method was newly developed to numerically predict the deformation of seawalls covered with armored embankments during earthquakes. The movements of the armor units were calculated by DE analysis and deformations of the caisson, rubble mound, sand seabed and backfill were calculated by FE analysis considering the non-linearity of the soil materials based on the effective stress. Dynamic interaction was taken into account by delivering the nodal displacements of the finite elements or the nodal forces converted from the contact forces through the imaginary distinct elements defined at the boundaries between the DE and FE domain. The applicability of this method to the prediction of the deformation of seawalls was verified through numerical simulations of the centrifuge model test.

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Seismic records obtained from a seismometer array located in downtown Tokyo Japan for about ten years were inversely analyzed to estimate the dynamic soil parameters. Due to the illposed nature of the problem, the simple and often used "least square method" does not properly estimate the parameters. The Extended Bayesian Method combined with the Akaike Bayesian Information Criterion was introduced to overcome this difficulty. The results obtained were compared with dynamic triaxial test results obtained at the time of the seismometer installation. The shear moduli agree quite well with the estimated results, however the damping ratios estimated are slightly higher than the ones obtained in the laboratory.

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This paper concerns the stability against overturning of the caissons on rubble mound subjected to wave loading. A theoretical discussion is first made of the stability of a leaning caisson during wave loading, as a single degree-of-freedom system. The expression for the lower bound of driving moments sufficient to overturn a given caisson is derived. A review is then made of the damages induced to a composite breakwater, which consisted of two adjoining Stretches and C with slightly different sizes of caissons. Attention is called for the observation that most of the caissons in Stretch were overturned, whereas no caissons in Stretch C were brought into overturning. This fact is examined in detail in the light of the theory of overturning, making it possible to estimate the destructive wave heights that are compatible with the observed patterns of damage in Stretches and C of the composite breakwater.

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The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the ^116mIn activity. Directional correlations are also measured for 818–1293 and 1097–1293 keV cascades. The M1-2 mixing ratio δ, and the 0-2 mixing ratio μ_k are obtained for 818. keV +→2₁⁺ transition to be δ=1.52−

0.22

+0.26, and μ_k≤6.1×10−

4

respectively. The

E

2 branching ratio

B

(

E

2;

2₂

+→0_g⁺):

B

(

E

2;

2₂

+→2₁⁺):

B

(

E

2;

2₂

+→0₁⁺) is determined to be 0.0158:1.0:5.

86

.

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Using two direct introduction methods, DNA synthesis or cell proliferation activities of three purified proteins from . coli, namely, human papillomavirus (HPV) proteins of type 16, a mutant type 16 (24 C-G) (transformation defective) and type 6, were measured in mouse fibroblast, C127 cells. By a microinjection method, the order of the cell mitotic indexes for the three proteins as determined by 5-bromo-2'-deoxy-uridine (BrdU) staining was type 16, 6 and 16 (24 C-G). By the osmotic shock method, the ³H-TdR incorporation and coloration by (3-carboxymethoxy phenyl)-2-(-sulfophenyl)-2H-tetolazorium (MTS) for the three proteins correlated with the pRb binding and focus forming activities previously reported (hunger et al. 1991). These results indicate that the simple osmotic shock method for direct protein introduction may be generally useful for transformation assays of oncoproteins.

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The filtration compatibility of soil-geotextile systems has been assessed experimentally in the laboratory with the gradient-ratio test. A nonwoven geotextile was used against a variety of model soils that were prepared from glass beads. They exhibited a range of fines content, in both gap-graded and broadly-graded size distributions. Filter blinding and clogging, if it happens, occurs within hours of initiating unidirectional flow. The zone of soil above the geotextile that is influenced is relatively thin. In gap-graded soils, the movement of fine particles appears to occur at a conditioh of D₈₅/D₁₅>. A new dimensionless index is proposed to quantify the internal stability of gap-graded soils.

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Using the so-called pseudo-static method, a stability analysis was made for the mountain slide that took place at Mitake-iriya village at the time of the Izu-Ohshima-Kinkai earthquake of January 14, 1978. Undisturbed samples of volcanic clay were obtained in blocks from the exposed surface of the deposit identified to have been the sliding surface. The partially saturated clay samples were tested under consolidated undrained conditions using the triaxial test equipment. Dynamic axial stresses with irregular time histories were applied to the specimens in combination with statically sustained axial stresses to determine the soil strength under the conditions simulating in-situ states of stress during the earthquake. The results of the tests were expressed in terms of the Mohr-Coulomb type failure criterion which showed that, while the angle of internal friction remained almost unchanged, the cohesion component in irregular loading increased above values obtained in the static loading. Using the strength parameters thus determined, a pseudo-static analysis was made to check the stability of the soil masses that had actually slid during the 1978 earthquake. The maximum horizontal acceleration required to cause the slide was computed. The computed accelerations were shown to cover a range between 400 and 500 gals which is consistent with the range estimated by other investigators on the basis of overturning of tombstones in the vicinity of the slide area.

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Based on the methods previously presented by the authors (Yasuhara et al., 1992, 1994, 1996) for predicting the degradation in strength and stiffness of soft clays in the course of cyclic loading, a methodology has been developed to estimate the cyclic loading-induced settlements. The method also includes not only immediate settlements but also post-cyclic long-term settlements due to dissipation of cyclically induced excess pore pressures in soft soils. The simplified formulae included in the proposed methodology are given as functions of the amplitude of cyclic-induced excess pore pressure normalized by the confining pressure, u/p'_c, plasticity index I_p and factor of safety against bearing capacity failure, F_s. The calculations of cyclic-induced settlements were conducted for soft soil deposits with different index and geotechnical properties. The results calculated using the proposed methodology are presented in the form of a design chart to give the settlement versus normalized excess pore pressure ratio relations including the effects of the plasticity index and safety factor for bearing capacity. An example of the calculated results using the proposed procedure for the earthquake-induced settlements of embankments founded on soft clay, is presented to demonstrate the practicality of the method for design at fields.

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