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.

抄録全体を表示

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.

抄録全体を表示

The phase diagrams of the Ni-Mo- and Ni-W- ternary systems in the region of less than 50mol% were constructed by thermodynamic calculation, based on the data obtained by thermodynamic measurement of the related materials. We found three ternary eutectic points and three or two ternary peritecto-eutectic points as follows:
:L (1365K, 71.mol%Ni-6.0mol%Mo-.mol%)=(Ni)++
:L (1355K, 62.mol%Ni-2.mol%Mo-30.mol%)=++
:L (1445K, 42.0mol%Ni-30.6mol%Mo-10.3mol%)=(Ni)+NiMo+
P₁:L (1812K, 34.mol%Ni-42.3mol%Mo-.mol%)+MoB=+
P₂:L (1633K, 42.3mol%Ni-40.mol%Mo-17.3mol%)+Mo=+
P₃:L (1812K, 53.mol%Ni-33.mol%Mo-12.mol%)+Mo=NiMo+
:L (1622K, 51.0mol%Ni-31.6mol%W-17.mol%)=(Ni)+W+
:L (1260K, 71.0mol%Ni-.0mol%W-.0mol%)=(Ni)++
:L (1291K, 65.mol%Ni-.mol%W-29.mol%)=++
P₁:L (2115K, 23.mol%Ni-43.1mol%W-33.1mol%)+WB=+
P₂:L (1657K, 48.mol%Ni-33.1mol%W-18.0mol%)+=W+
The calculated phase diagrams are expected to be useful for the development of new Ni-based heat-, corrosion- or wear-resistance alloys.

抄録全体を表示

The Gujarat earthquake in India occurred in January, 2001, and caused significant damage in the province of Gujarat. The Japanese Geotechnical Society sent a small reconnaissance team to the damaged region after the quake. The present text presents the report from this activity. The major attention of the team was focused on geotechnical aspects of the damage which were related to earthfill dams and harbor land fills. It was found that a significant portion of damage was concentrated in fills resting on soft natural soils. Swedish weight soundings which were conducted at two places demonstrated the existence of such a soft subsoil. From this, it was concluded that amplification of earthquake shaking as well as the permanent deformation in the soft foundation soil induced such kinds of damage as subsidence, cracking, and lateral spreading in overlying artificial fills. For the better seismic resistance of those affected fills during future earthquakes, the improvement of soft subsoil seems essential.

抄録全体を表示

The boundary element method expanded in frequency domains is presented to analyze the dynamic interaction between an embedded flexible rectangular foundation and soil with consideration of the obliquely incident waves. Numerical results describing the influence of the flexibility of the foundation on the dynamic responses of the foundation due to obliquely incident waves indicate that the flexibility of actual foundations can diminish the reduction of translation responses and increase the rotational responses in the high frequency range. These phenomena are more conspicuous as the embedment ratio is larger and the value of the wave velocity ratio of the soil and the foundation approaches to unity. When the high frequency components of the input ground motion are important and the basement has higher flexibility (for example ₂v_s/₁v_s >0.), the analysis method which considers the basement as a rigid foundation may lead to unsafety estimations and the estimation of the flexibility of the foundation is necessary as analysing the effective input motion with consideration of the incident waves.

抄録全体を表示

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.

抄録全体を表示

2-Benzyl--chloro--mercapto-3 (2H)-pyridazinone (1) was heated in ethanol under reflux for 10 hours to form concurrently 2, -dibenzyldipyridazo [, - : ', '-]-1, -dithiin-1, 6 (2H, H)-dione (Ia) (57% in yield) and 2, -dibenzyldipyridazo [, - : ', '-]-1, -dithiin-1, (2H, H)-dione (IIa) (14% in yield). Assignment of the two products to the corresponding structures is established by their physico-chemical constants and chemical behaviors. The concurrent formation of the dipyridazo [, - : ', '-]-1, -dithiin-1, 6 (2H, H)-dione and the -1, (2H, H)-dione were observed in, not only heating -chloro--mercapto-3 (2H)-pyridazinones (1-3) in polar solvent, but warming -mercapto--chloro-3 (2H)-pyridazinones (-6) in the presence of potassium carbonate in DMF. For the interpretation of the reaction, keto-thioketo carbenes as active intermediate species and a reversible interconversion among them are suggested on the basis of the fact that there was nonexistence of an equilibrium between the two compounds, such as Ia and IIa, under the reaction condition and a trapping keto-thioketo carbene species as 2-phenylimino--benzylpyridazo [, -d]-1, 3-dithiol- (H)-one (IVa) (14% in yield) along with the major products, (Ia) and (IIa), was furnished by warming 1 with phenylisothiocyanate in the presence of triethylamine in dry benzene. On the contrary, participation of a reversible interconversion between Ia and IIa, to a considerable extent, with the concurrent formation of them in the case of benzylation of either Ib or IIb, by warming with benzylchloride in the presence of potassium carbonate in DMF at 80°, might not be neglected, because an attempted approach to an equilibrium between Ia and IIa in a similar reaction condition except the use of benzylchloride realized, whereas non-existence of an equilibrium between Ib and IIb in the similar reaction condition was observed.

抄録全体を表示

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, () 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.

抄録全体を表示

This study aimed to determine the prevalence of fecal carriage of extended spectrum β-lactamase (ESBL) and/or plasmidic AmpC β-lactamase (pAmpC) producing Escherichia coli among dogs (n=428) in Turkey. Polymerase chain reaction (PCR) and sequencing were used to characterize genes encoding β-lactamase and plasmid mediated quinolone resistance (PMQR). Antimicrobial susceptibility testing and PCRs for virulence genes and phylogenetic groups were also performed. Cefotaxime resistant

. coli isolates were detected in 95 (.2%) of the swab samples. Sequencing analysis results showed occurrence of various β-lactamase genes: bla_CTX-M-15 (62), blaTEM-

1b

(42), bla_CMY-2 (

22

), bla_CTX-M-3 (16), bla_CTX-M-1 (15), bla_OXA-1 (

9

) and bla_SHV-12 (3) alone or in combination. The most frequently encountered phylogenetic group was group A₁ (35.

8

%), followed by group D₂ (

22

.1%),

B

1 (15.

8

%), D₁ (

9

.

5

%), A₀ (

7

.

4

%),

B2₂

(

5

.3%) and

B2₃

(

4

.2%), respectively. PMQR genes, aac(6’)-Ib-cr, qnrS1 and qnrB10 were detected in 25.3, 10.

5

and 1.1% of the isolates, respectively. While all isolates were susceptible to imipenem and amikacin, resistance rates to non-β-lactam antibiotics ranged from 20.0% for tobramycin to 56.

8

% for tetracycline. The virulence genes were only detected in 34 (36.2%) of the isolates and this isolates carried single or various combination of virulence genes of iucD, papC, papE, f17a-A and eaeA. Four isolates were identified as human virulent pandemic CTX-M-15 producing

E

. coli clone O25

b

:ST131/

B

2. To the best of our knowledge, this is the first study to show fecal carriage of ESBL/pAmpC type β-lactamase producing

E

. coli isolates among dogs in Turkey.

抄録全体を表示

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.

抄録全体を表示

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.

抄録全体を表示

From the black coral Antipathies dichotoma, a sphingolipid (2S*,3S*,,)-2N-[tetradecanoyl]-(),()-icosadiene-1,3-diol (1) and a steroid ()-methylcholesta-,-diene-1α,3β,-triol (2) were isolated. Other known compounds, 3β,-dihydroxy-cholest--ene (3), (,24S),,-epidioxy-24-methylcholesta-6,-dien-3β-ol () and (,24S),,-epidioxy-24-methylcholesta-6,(11),-trien-3β-ol (). The structures were established on the basis of NMR spectroscopic analysis and comparison with literature. The antibacterial activity of five compounds was evaluated.

抄録全体を表示

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. 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.

抄録全体を表示

Eight new sterols, , -epidioxy-(, 24R)-23-methylergosta-6, -dien-3β-ol (1), 3β, , -trihydroxy-(, 24R)-23-methylergosta-, -dien-6-one (2), 3β, , -trihydroxy-(24S)-ergost--en-6-one (3), 3β, , , 14α-tetrahydroxy-(, 24R)-ergosta-, -dien-6-one (), (, 24R)-ergosta-, -diene-3β, , 6α, -tetrol (), , -epidioxy-3β-hydroxy-(, 24R)-ergosta-, -dien-6-one (6), , -epidioxy-3β-hydroxy-(24S)-ergost--en-6-one () and , 6α-epoxy-(, 24R)-ergosta-, -diene-3β, , 14α-triol (), have been isolated from five edible mushrooms, Lentinus edodes, Flammulina velutipes, Hypsizigus marmoreus, Pleurotus ostreatus and Pholiota nameko together with fifteen known ones (-23), of which two (16 and 17) are reported for the first time from a fungal source. The structures of these new compounds were elucidated on the basis of their spectral data.

抄録全体を表示

Brassinolide analogues, (R, 23R, 24R)-2α, 3α, , 23-tetrahydroxy--homo--oxa--ergostan-6-one (24-epibrassinolide) (10) and (S, 23S, 24R)-2α, 3α, , 23-tetrahydroxy--homo--oxa--ergostan-6-one (), were synthesized from brassicasterol (3a) in five steps and with ca. 20% overall yield. The key steps are the direct formation of (, 24R)-3α, -cyclo--ergost--en-6-one () from brassicasterol mesylate (3), the acid-catalyzed rearrangement of to (, 24R)--ergosta-2, -dien-6-one (6), and the Baeyer-Villiger oxidation of the tetrahydroxy -ergostan-6-ones and .

抄録全体を表示

Six new sterols, , 6α;, -diepoxy-(, 24R)-ergost--ene-3β, -diol (1), , 6α;, -diepoxy-(, 24R)-ergost--ene-3β, -diol (2), , 6α-epoxy-(, 24R)-ergosta-, -diene-3β, -diol (3), (, 24R)-23-methylergosta-, -diene-3β, , 6β-triol (), (, 24R)-23-methulergosta-, -diene-3β, , 6β, -tetrol () and (24S)-ergost--ene-3β, , 6β, -tetrol (6), have been isolated from seven mushrooms, Amanita pantherina, Amantia virgineoides, Lactarius piperatus, Lyophyllum shimeji, Tricholoma portentosum, Hypsizigus marmoreus and Lentinula edodes together with eighteen known ones (-24). The structures of these new compounds were elucidated on the basis of their spectral data.

抄録全体を表示

抄録全体を表示

Stereoselective synthesis of the , -syn, , 6-anti adducts (14 and 16) on the aldol condensation of the Z (O)-lithium enolate, derived from the -enone (2), to α-alkoxy aldehydes (12 and 13) was proved via the successive intramolecular Diels-Alder reaction.

抄録全体を表示

In the seismic analysis of pile foundations the soil is often assumed to be an elastic material and the pressure at the soil pile interface is not limited during the analysis. This may result in a considerable error, as the computed pressure from an elastic analysis may go well beyond the ultimate lateral pressure of real soil. In fact, significant yielding at the soil-pile interface has been observed during real earthquakes, and also in laboratory tests. The yield zone is usually near the ground surface where the effect of inertial force due to the superstructure is higher. This yielding redefines the pile response, and in general cannot be ignored. In order to examine the effects of soil yielding on the internal pile response during earthquakes an approximate analysis is described in this paper which is an extension of a static method developed by the second author (1982) for the analysis of piles subjected to lateral soil movement. This method is then used to investigate the effects of soil yielding on the internal response of piles through a comparative study in which real earthquakes are used. It is shown that for strong earthquakes and heavily loaded piles the soil yielding may considerably increase the amount of maximum pile moment developed in the pile. A marked difference in the effects of yielding on the pile moment and shear is observed and discussed.

抄録全体を表示