The significant influence of surface roughness of discontinuity surfaces is a quantity that is fundamental to the understanding of shear strength of geological discontinuities. This is due to reason that the shear str...
The significant influence of surface roughness of discontinuity surfaces is a quantity that is fundamental to the understanding of shear strength of geological discontinuities. This is due to reason that the shear strength of geological discontinuities greatly influenced the mechanical behavior of a rock mass especially in stability evaluation of tunnel, foundation, and natural slopes. In evaluating the stability of these structures, the study of peak friction angle (Φpeak) of rough discontinuity surfaces has become more prominent seeing that the shear strength is a pivotal factor causing failures. The measurement of peak friction angle however, requires an extensive series of laboratory tests which are both time and cost demanding. With that in mind, this publication presents an approach in the form of an experimentally determined polynomial equation to estimate peak friction angle of limestone discontinuity surfaces by measuring the Joint Roughness Coefficient (JRC) values from tilt tests, and applying the fore mentioned empirical correlation. A total of 1967 tilt tests and JRC measurements were conducted in the laboratory to determine the peak friction angles of rough limestone discontinuity surfaces. A polynomial equation of ɸpeak = −0.0635JRC2 + 3.95JRC + 25.2 that exhibited 0.99 coefficient of determination (R2) were obtained from the correlation of JRC and peak friction angles. The proposed correlation offers a practical method for estimation of peak friction angles of rough discontinuity surfaces of limestone from measurement of JRC in the field.
Alkaline membranes and their applications were the main topic of the Workshop on Ion Exchange Membrane Applications, held in June 2014 in Bad Zwischenahn, Germany. The workshop saw 35 experts from nine nations listen ...
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Alkaline membranes and their applications were the main topic of the Workshop on Ion Exchange Membrane Applications, held in June 2014 in Bad Zwischenahn, Germany. The workshop saw 35 experts from nine nations listen to 19 talks given by membrane specialists from academic research facilities and professionals from industry. To give an impression of the workshop programme, this article presents four excerpts from the scientific talks.
The N-oxidation of alkylpyridines by hydrogen peroxide is a reaction widely used in the pharmaceutical industry. This reaction is accompanied by the undesired gas-generating decomposition reaction of hydrogen peroxide...
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ISBN:
(纸本)9780816910670
The N-oxidation of alkylpyridines by hydrogen peroxide is a reaction widely used in the pharmaceutical industry. This reaction is accompanied by the undesired gas-generating decomposition reaction of hydrogen peroxide. The oxygen generation, combined with the flammability of the alkylpyridines, represents a serious hazard of fire and explosion. In this work, a new operation strategy and reactor type for the N-oxidation of alkylpyridines are proposed based on calorimetrically obtained data. Previous studies on this system [8] showed that Langmuir-Hinshelwood type kinetics fits well with the Noxidation of this family of reactions and that increased temperature and catalyst concentration favor the N-oxidation reaction. New calorimetric measurements have been performed over an extended range of temperatures and catalyst concentrations in a closed reactor. These measurements confirm that the N-oxidation of alkylpyridines can actually be performed in a much more efficient and inherently safer manner if a closed reactor is used. The advantages and characteristics of such a reactor are explained and a preliminary design is proposed.
It is common for small tandem peptide multimer genes to be indirectly inserted into expression vectors and fused with a protein tag. In this study, a multimer of the tandem angiotensin I-converting enzyme inhibitory p...
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作者：
KORWEK, ELEdward L. Korwek
Ph.D. J.D. is associated with the law offices of Keller and Heckman 1150 17th St. N.W. Washington D.C. 20036.REFERENCES Committee on Recombinant DNA "Potential Biohazards of Recombinant DNA Molecules" Nature250: 175 (1974) Proc. Nat. Acad. Sci.71: 2593 (1974)Science185: 303 (1974).|Article|Fed. Regist.48: 24556 (1983).Milewski
E. Editor's Note. Recombinant DNA Tech. Bull.4: i (1981).Inside EPA 4 1 (1983). EPA has already held a meeting and published a draft report on the subject of its regulation of this area under the TSCA. EPA "Administrator's Toxic Substances Advisory Committee Meeting"
Fed. Regist.48: 8342 (1983) Regulation of Genetically Engineered Substances Under TSCA
Chemical Control Division Office of Toxic Substances Office of Pesticides and Toxic Substances Environmental Protection Agency Washington D.C. (March 1982). Congress also recently held a hearing on the subject of existing federal authority over the release of R-DNA-containing organisms into environment. M. Sun Science221: 136 (1983).Sects. 2-30 15 U.S. Code sects. 2601-2629 (1976 and Supp. V 1981). Hereinafter all references in the text to TSCA refer to the section numbers as enacted and not to the corresponding U.S. Code sections.The Administrative Procedure Act specifically states that the reviewing court shall "hold unlawful and set aside agency action findings and conclusions found to be hellip in excess of statutory jurisdiction
authority or limitations or short of statutory right. hellip " 5 U.S. Code
sect. 706(2)(C) (1976).PHS Act 42 U.S. Code sects. 217a and 241 (1976) Charter
Recombinant DNA Advisory Committee Department of Health and Human Services (1982).Korwek E. Food Drug and Cosm. L. J.35: 633 (1980) p. 636.Although DHHS has some authority under Section 361 of the PHS Act to regulate R-DNA materials that cause human disease and are communicable most types of experimentation would not fall into this category. Because of this limitation the Sub committee of the Federal
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