Skin Friction and Pile Design

The skin friction of pile is found as a parameter of pile shaft displacement. It will not be a simple/constant values for each type of soil/weathered rock. Pile load test data shows skin friction grows to maximum strength at certain displacement and then reduces to residual strength. Due to this property, the main active skin friction zone is shifted downwards with the increase of load. From the shared ratio of total skin friction in pile bearing capacity, the share ratio of skin friction is found related with pile length. This means that for 30m long pile, the skin friction share is approx.95% of bearing capacity. The shared ratio shows almost constant value for each pile under 100% ~ 300% of design load if there is no failure in the pile. From this point of view, the failure of pile bearing mechanism will be due to the change of skin friction share ratio

The Statical Characteristics of the Wall Reattachment Fluidic Devices

This study is concerned with a developed method for obtaining the quantitative relations between the input or output characteristics and the geometric parameters of the wall reattachment fiuidic devices. In this report, it is shown analytically and experimentally that the characteristics can be represented by the functions, dependent on the geometric parameters only, with non dimensional quantities, if the Reynolds number at the main jet nozzle is sufficiently large. Accordingly, the quantitative relations of the geometric parameters may be analyzed more easily

Analysis of Warren's Fluidic Counter

Though the Warren's fluidic counter has a very simple construction, the matching problems of the main jet supply pressure with the input pulse may take place and so there may be some working conditions under which this counter cannot work. Up to now, these matching problem have been hardly investigated. In this study the following things were systematically investigated : the static and dynamic characteristics of the memory and the control flip-flops with different geometric parameters, the behavior of the counter which are constructed by two of them, and finally the fow in the counter. The obtained results are as follows : (1) Under some clear and accurate conditions, the Warren's counter works satisfactory without any au iliary circuit. (2) In the control part, the input pulse flow don't reattach on any side wall, but branches into both output ports. (3) The necessary condition under which the Warren's counter behaves successfully is as follows : (1-2α)Q(i)>Q(ms), where α is the distribution factor of the control part, is the input pulse flow rate and is the switching control flow rate of the memory part

Effects of Pointed Splitter Position on Attached Jet Switching

In this report, the effects of splitter position on the attached jet were experimentally investigated for the purpose of discussing the applicability of a usual mathematical model without splitter. As results, the followings were confirmed, (l) For the splitter distance shorter than the critical distance, the pressure in the bubble lowers and the jet radius of curvature shortens. (2) At the ratio L(s)/D=4~5, the switching control flow rate becomes maximum. And bordering this value, the effects of splitter position on the switching are quite conversely. For the splitter distance longer than the above value, the switching control flow rate decreases, as increasing the distance. (3) For the splitter distance of 1.5~2 times critical distance, the switching is almost never affected by the splitter

Biologically Active Compounds. III. The Synthesis of α-Alkylamino-α-arylacetamides

A series of α-monoalkylamino-α-arylacetamides and α-dialkylamino-α-arylacetamides have teen synthesized via the corresponding nitriles. Some of these compounds have been found to exhibit moderate activity as herbicides

New Stable Sulfonium Ylides. 1-Dimethylsulfuranylidene-l-phenylsulfonyl-2-propanone and Related Compounds

The preparation of the title compounds as a new type of stable S-ylides has been described. The reaction of 1-dimethylsulfuranylidene-1-phenylsulfonyl-2-propanone (IIb) with lithium aluminium hydride was found to result in the formation of trans-phenylpropenylsulfone (IV), phenylsulfonyl-2-propanone (Ib), and an unidentified paraffin as major products

Effects of Wall Length and Vent on Attaching Jet and Its Switching

The effects of some geometries peculiar to the wallattachment fluidic devices on the attaching jet flow and the switching mechanism were experimentally made clear. And the propriety of the analytical mOdel, which has been used for the theoretical study of these devices, was investigated. The results can be summarized as follows: 1) The existing analytical model of the attaching jet flow is not applicable to the case of relatively short wall length of vent distance. 2) The attaching jet flow never detaches from a sufficiently long side wall with vent. 3) The switching mechanism of the vent type device is always the opposite wall switching. 4) From the viewpoint of the output characteristics of the device, the vent distance has a lower limit in relation to the vent width

Lactone Carboxylic Acids. IV. Reaction of Ethyl Chloroarylpyruvate with Ethyl Malonate

The condensation of ethyl chloroarylpyruvate (Ⅰ) with ethyl malonate in the presence of sodium ethoxide afforded γ-aryl-α,β-dicarbethoxy-⊿(β),γ-butenolide. On the basis of the chemical and spectral evidences, the structure of the product (II) has been elucidated. This reaction provides new routes to α,β-dicarboalkoxy-γ-butyrolactones and/or to γ-ketocarboxylic acids