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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Repetitive liquefactions in angular and subangular gravels from an alluvial fan, in the case of two earthquakes with accelerations lower than that of a former which had caused liquefaction some months before, are described. The liquefaction took place from the surface, down to a depth of approximately 10 m. Water laden with sediments spouted out for some tens of minutes after the strong motion ceased. Knowledge of the grain size distribution of the sediments inside the body of the alluvial fan roughly defines the areas of the fan prone to future liquefaction. Non-repetitive liquefaction in overconsolidated fine fluvio-lacustrine sand of glacial origin at the unusual depth of 14 m to 16 m is also described. From the observation of sand lifted up for 10 m inside a large diameter well, and of that which spouted out from several microvents, it was estimated that extra-pore pressure was close to lithostatic conditions. Nevertheless, modeling of intrinsic pore pressure buildup on the DESRA2 programme gives lower values than the experimental one. Geotechnical characteristics of the 12 m-thick sandy stratum indicate that the upper part is unusually soft, either due to water circulation or past repetitive liquefactions which prevented reconsolidation. It is suggested that excess pore pressure generated by the earthquake was also due to redistribution of pressure from adjacent sediments.

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Piled bridge abutments on soft clay may be loaded laterally from horizontal soil movements generated by the approach embankment. A limited number of field trials have been described in the literature, although the data are generally limited in extent, complicated by variations in geometry or soil conditions, or of relatively poor quality. This paper presents the results of a series of centrifuge model tests aimed at clarifying the behaviour of piled bridge abutments on soft clay. The centrifuge modelling techniques and equipment used are initially described. Attention is focused on the induced pile bending moments and deflections, and the response is shown to be critically dependent on the factor of safety of the embankment against failure. The effects of variations in pile rake, embankment geometry and abutment wall loading are described. The response of pile groups with time after embankment construction is outlined and the causes of time dependent behaviour identified.

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Circuit techniques to enhance the linearity of input-voltage-to-current (V/I) conversion and to increase the output impedance of a current source by compensating for the low intrinsic gain of a transistor were introduced to realize a high-frequency operational transconductance amplifier (OTA) for a low supply voltage using sub-100-nm CMOS processes. Applying these techniques, a MOS th-order Gm- linear-phase low-pass filter (LPF) was realized using a 65nm CMOS process. A simplified biquad LPF that can serve as a component of a th-order LPF was newly developed by replacing OTAs with resistors. As a result, the -3dB frequency bandwidth, group delay ripple, 3rd-order distortion, and 3rd-order input intercept point (IIP3) were 200MHz, 2.2%, ≤ -55dB with a 100MHz input, and +10.3dBm, respectively, all with a ±.1Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a 1.2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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The small strain stiffness and anisotropic nature of two sands with different geological origin have been determined via laboratory seismic tests performed in a triaxial cell. Dry triaxial reconstituted specimens of Ticino river silica sand (TS) and of Kenya carbonatic sand (KS) were subjected to isotropic and anisotropic states of effective stress ; then both shear and constrained compression waves were propagated in vertical, horizontal and oblique directions by means of five couples of piezoelectric transducers especially arranged in the specimens. The propagated compression and shear waves allow the assessment of the constrained and shear moduli respectively, at very small strains where, as a first approximation many soils can be assumed, from an engineering point of view, to behave as an elastic cross-anisotropic medium with a vertical axis of symmetry. This paper, after a brief description of the novel measuring technique adopted and of the tested materials, summarises the test results and their interpretation in order to separate the effects of the fabric anisotropy from those produced by the state of effective stresses on soil stiffness. The stiffness and anisotropic response of the two tested sands are compared. Finally the results enable us to establish five independent constants of the cross-anisotropic elasticity model, which appears to be appropriate to reproduce the behaviour at small strain of the two sands.

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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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This paper outlines a mathematical description of the stress dilatancy behaviour of granular materials which accounts for stress level and void ratio dependencies. The consideration of these aspects has important implications in the modelling of granular material behaviour. In fact, granular material mechanical response is largely dominated by the evolution of dilatancy, fabric and void ratio histories. The starting point in this study is the well established Rowe's theory which is revisited and ultimately modified by introducing a factor linked to governing state parameters in order to describe the complete behaviour of granular materials during deformation. Numerical simulations of triaxial tests on granular materials at different void ratios and stress levels are herein presented to illustrate the model.

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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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As a fundamental study on dibenzothiepins, reaction of 11-phenyl-6, 11-dihydrodibenzo [, ] thiepin-11-ol (10) or 11-chloro-11-phenyl-6, 11-dihydrodibenzo [, ] thiepin (14) with triphenylmethyl cation or was examined under various conditions. 11-Phenyl-6, 11-dihydrodibenzo [, ] thiepin-11-ylium salt (8) was isolated as a black powder (perchlorate) and a green powder (hexachloroantimonate), but salt was obtained only as a solution. Treatment of the hexachloroantimonate with excess of was found to result in a novel dehydrocyclization reaction to give selectively , 13-dihydrofluoreno [1, a, -, d] [2]-benzothiepin-13-ylium hexachloroantimonate (19). Some discussions were made on the mechanism of the formation of 19.

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Activity-directed isolation of the ethyl acetate, methylene chloride and n-hexane fractions of Gloiopeltis furcata resulted in the isolation of 18 compounds. Their structures were elucidated as 2-(3-hydroxy--oxotetrahydrofuran-3-yl)acetic acid (1), glutaric acid (2), succinic acid (3), nicotinic acid (), ()--hydroxyhex-2-enoic acid (), cholesterol (6), -hydroxycholesterol (), uridine (8), glycerol (), -(hydroxymethyl)-2-methoxybenzene-1,3-diol (10), (,)--oxodeca-,-dienoic acid (11), (Z)-3-ethylidene--methylpyrrolidine-2,-dione (12), dehydrovomifoliol (13), loliolide (14), cholesteryl stearate (15), palmitic acid (16), cis-,8,11,14,17-eicosapentaenoic acid (17) and α-linolenic acid (18) on the basis of spectroscopic and chemical evidences. Their anticholinesterase and antioxidant activities were evaluated via inhibitory activities on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) as well as scavenging activities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and peroxynitrite (ONOO⁻). All isolated compounds (1—18) exhibited moderate AChE inhibitory activities with IC₅₀ values ranging from 1.14—12.50 μg/ml, whereas 1, , , 17, and 18 showed mild BChE inhibitory activities with IC₅₀ values ranging from .57—15.89 μg/ml. Although most of the compounds isolated were lacking the scavenging activity on DPPH radical and ONOO⁻, and 10 showed good DPPH radical scavenging activity, and , 10, and 16 showed potent ONOO⁻ scavenging activity.

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