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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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 -(3-hydroxy--oxotetrahydrofuran-3-yl)acetic acid (1), glutaric acid (), succinic acid (3), nicotinic acid (4), ()-4-hydroxyhex--enoic acid (), cholesterol (), -hydroxycholesterol (), uridine (8), glycerol (), -(hydroxymethyl)--methoxybenzene-1,3-diol (10), (,)--oxodeca-,-dienoic acid (11), (Z)-3-ethylidene-4-methylpyrrolidine-,-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--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. 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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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

% 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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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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From the fronds of Polystichum tripteron (KUNZE) P_R. a new norcarotenoid glycoside was isolated and shown to be (R, , R)--hydroxy-megastigma-4, -dien-3-one--O-β--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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A new analytical method is proposed for determining the inextensible grid reinforcement pullout resistance and pullout force/pullout displacement curve by using basic backfill soil and grid reinforcement properties. The pullout skin friction resistance/pullout displacement relationship is simulated by linear elastic-perfectly plastic model. A hyperbolic model has been proposed to represent the pullout bearing resistance/pullout displacement relationship in which the maximum bearing resistance of a single bearing member is determined using a new bearing capacity equation proposed in this paper. The influences of the grid bearing member spacing ratio, S/, the bearing member deflection rigidity, and the pullout softening behavior on the mobilization of pullout bearing resistance are explicitly included in the proposed model. Good agreement has been obtained between calculated values and laboratory test results.

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Two new partially saturated tricyclic ring systems, , a, , 8, , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (3a and 3), and -thiepins (4a and 4) were synthesized. Compounds 4a and 4 were desulfurized to give a pair of isomeric -methylbenzoylcyclohexanes (10a and 10). Deuterated 4a and 4 (11a and 11) were prepared starting from butadiene- (12). The stereochemical features of 3a (trans), 3 (cis), 4a (trans) and 4 (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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(,)-,3-エポキシ-3,,11,11-テトラメチルシクロウンデカ-,-ジエン()をフムレン1((,,)-3,,11,11-テトラメチルシクロウンデカ-,,-トリエン)より合成する既知の合成法は実際に牧率が低く合成的に問題がある.さらに,の合成はその反応性や物性の研究のために簡単に高牧率で行われることが望まれる.今回,の新たな合成法と簡便な精製法を見いだし,を高牧率で1から合成することができたので報告する.1のジエポキシ化,続く再結晶により得られたジエポキシド(8)は二価のチタンにより還元されて,1(273%)と8(25%)と少量の3を含むを主生成物(42.%)として与えた.1と3は原料として再利用できる.の精製は1と同様硝酸銀(AgNO₃)錯体の結晶で行い,純粋なは1から通算牧率32.0%で得られた.の既知方法による合成は4段階の反応と数回のカラム分離及び10%AgNO₃含浸シリカゲルカラム分離を必要とし牧率が極端に低い.今回,新しいの合成法は段階の反応で1回のカラム分離と再結晶により高い通算牧率を示す.

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The main objective of this paper is to compare safety factors obtained from Morgenstern-Price, Janbu and Spencer methods with the factors calculated from the modified variational approach (Leshchinsky and Huang, 1992a). Such comparison is essential since there is no mathematical proof that the variational analysis indeed yields a minimum and thus, physically produce significant results. The safety factors compared well, indicating the variational analysis is on a par with acceptable existing rigorous methods. Availability of a user-friendly computer code may make the variational analysis useful to practicing engineers. However, its greatest potential at the moment is in 3- applications; i.., unlike other methods, its extension to 3- is straightforward.

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Alfven resonance effects on the evolution of a magnetic island driven by an externally applied perturbation are investigated for rotating plasmas. The simulation results show the importance of Alfven resonance for obtaining a perturbed current profile and estimating a critical value of the external perturbation, beyond which the magnetic island grows rapidly. The nonlinear evolution of the externally driven magnetic island is also investigated at low and high viscosities ν. It is shown that the transition phase accompanying the secondary reconnection at the initial X-point in the driven magnetic island evolution occurs in low resistivity and viscosity plasmas.

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11-Amino-, a, , 8, , 10, 10a, 11-octahydrodibebenzo[, ]thiepines (a-) and -oxepines (a-) were synthesized by the Leuckart reaction of , a, , 8, , 10, 10a, 11-octahydro-11-oxodibenzo[, ]thiepines (1a, )and -oxepines (a, ) followed by hydrolysis of the reaction products 4a- and a-, respectively. The four diastereomers, cis(a-H, 10a-H)-cis(10a-H, 11-H) a and a, cis(a-H, 10a-H)-trans(10a-H, 11-H) and , trans(a-H, 10a-H)-trans(10a-H, 11a-H)c and c, and trans(a-H, 10a-H)-cis(10a-H, 11-H) and , 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 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 M₀ and shear G₀ 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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The present paper aims at developing a simplified model for a stress-strain relationship at small strains up to an initial yielding of homogeneous saturated frozen sand. The modelling of elastic moduli for an ice-sand mixture as a composite geomaterial is first introduced based on previous studies, where a saturated frozen sand is treated as the icesand mixture. The applicability of modelling the elastic moduli under constant temperature is then discussed from the theoretical and experimental points of view. In addition, the hyperbolic stress-strain modelling of saturated frozen sand at small strain is presented. The effect of the volume fraction of sand, stiffness of sand inclusion and temperature changes on the elastic moduli and the stress-strain behaviour up to about 1-% axial strain, which is defined as an upper yield stress, are investigated through the model, whose applicability is verified in comparison with the experimental data.

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The radical scavenging reactions of a vitamin model compound, , , , , 8-pentamethylchroman--ol, with radicals from the Fe (II)-induced decomposition of a linoleic acid hydroperoxide, (Z, 11)-13-hydroperoxy-, 11-octadecadienoic acid, were examined extensively. When Fe (II) was added to a mixture of the vitamin model compound and the linoleic acid hydroperoxide in methanol, ()-trans-12, 13-epoxy-erythro-11-, ()-trans-12, 13-epoxy-threo-11-, (Z)-trans-12, 13-epoxy-erythro-11-and (Z)-trans-12, 13-epoxy-threo-11-(, , , , 8-pentamethylchromanoxy)--octadecenoic acids, and ()-13-hydroxy-12-methoxy-11-(, , , , 8-pentamethylchromanoxy)--, (10)-13-hydroxy-12-methoxy--(, , , , 8-pentamethylchromanoxy)-10-and (11)-13-hydroxy-10-methoxy--(, , , , 8-pentamethylchromanoxy)-11-octadecenoic acids were obtained as main products. The hydroxymethoxy acids are presumed to be derived from the epoxy acids. A possible reaction pathway for the formation of the products is discussed.

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