Petrology of the Beulah-Zap lignite bed, Sentinel Butte Formation (Paleocene), Mercer County, North Dakota

The Beulah-Zap lignite bed is one of several economically important lignites in the Sentinel Butte Formation (Paleocene). This lignite occurs as a subsurface unit in the Knife River Basin of Mercer and I Oliver counties of North Dakota. The Beulah-Zap lignite is a heterogeneous carbonaceous rock unit composed of megascopic and microscopic I components, which are lithotypes and macerals, respectively. Relationships between the maceral contents of the lithotypes follow patterns similar to those of bituminous coals. Coal petrology, the study of maceral and lithotype occurrence and I distribution, was applied to determine: 1) mode of coalification, and 2) depositional environment of the Beulah-Zap lign1te. The lignite seams were divided into lithologic units (lithobodies) I on the basis of petrographic features within the layers. These lithobodies range in thick Jess from 5 to BS cm. Lithotypes, the petrographic units within the lithobodies, were separated for various analyses and their relative abundances were estimated. Three distinct lithotypes in the Beulah-Zap lignite have been identified and average I abundances estimated as: vitrain (501.l, fusain (5%), and attritus (45%). Macerals were identified by reflected light microscopy. I Maceral groups were classified into three major groups on the basis of their relative reflectances. Individual maceral types within the same group I were differentiated by morphology. The morphology is related to the i maceral precursor and mode of coalification. The lithotype fusain is I rich in inertinite macerals such as fusinite and semifusinite. The attritus lithotype is composed of all three maceral groups in variable percentages: huminite (41-82%), inertinite (10-65%), and liptinite (4 13%). The identified liptinite macerals include sporinte, resinite, cutinite, and suberinite. The huminite maceral group, consisting mainly of ulminite, is the major constituent of vitrain. The lithotype and maceral occurrence and distribution suggests that the depositional environment of the Beulah-Zap lignite was a lacustrine marsh complex with a steady rate of subsidence and peat accumulation. The initial peat deposition occurred in water 1.5 to 2.0 m deep. Later stages of deposition occurred in shallow water ( Three processes are responsible for the coalification of the Beulah Zap lignite. These processes are: 1) humification, 2) gelification, and 3) fusinitization. The principal mode of coalification was humification. This process was the dominant type of diagenetic alteration in the middle of the seams. Gelification, the complete biochemical maceration, has also altered portions of the Beulah-Zap lignite. The gelification process is most pronounced immediately above the clay partings. Fusinitization, indicative of oxidizing conditions, was more frequent towards the uppermost part of the seams. Several local fusinized horizons are present in the middle section of the Beulah- Zap lignite

EINLEITUNG // WITCHY WITS *** SITUIERT, WIDERSPENSTIG, GEWITZT

FKW No. 71 deals with feminist aesthetics and politics referring to witchcraft. From critical, anti-capitalist, queer, and post-colonial positions, witchy arts and (her)stories are affirmed in complexly situated ways: both, historico-critically as well as post-humanist speculatively. Instead of being naïve, exoticizing, or idealizing, such references to witches are entangled and crafty. In what aesthetic forms, media settings, and semiotic-material constellations are such "witchy wits" cultivated? What is to be un/learned with various kinds of witchy wits

MODELING AND OPTIMAL CONTROL OF ABLE-BODIED AND UNILATERAL AMPUTEE RUNNING

The remarkable performances of amputee athletes in sprint competitions aroused media and scientific interest and led to the question whether running-specific prostheses can be an advantage with respect to able-bodied running. The aim of this study was to bring together motion capture data and Scientific Computing methods to analyze the running motions of an able-bodied and a unilateral transtibial amputee athlete. For each of them a rigid multibody system model was created. By application of optimal control techniques, the dynamics of reference running movements from motion capture data was reconstructed for both models. The able-bodied and the transtibial amputee sprinters rely on dissimilar actuation strategies to perform similar running motions

On specimen design for size effect evaluation in ultrasonic gigacycle fatigue testing

Literature datasets showed that gigacycle fatigue properties of materials may be affected by the specimen risk-volume, i.e., the part of the specimen subjected to applied stress amplitudes above a prescribed percentage of the maximum applied stress amplitude. The paper proposes a Gaussian specimen shape able to attain large risk-volumes for gigacycle fatigue tests, together with a general procedure for its design: wave propagation equations are analytically solved in order to obtain a specimen shape characterised by a uniform stress distribution on an extended length and, as a consequence, by a larger risk-volume. The uniformity of the stress distribution in the Gaussian specimen is numerically verified through a finite element analysis and experimentally validated by means of strain gauge measurement

Визначення кількості рослинних антиоксидантів для захисту гірких хмелевих речовин від окисної деструкції

Досліджено кінетику окиснення гірких речовин водного розчину екстракту хмелю у прискорених умовах з різною концентрацією антиоксидантів із рослинної сировини. Визначено ефективну концентрацію антиоксидантів із кори дубу, трави звіробою та трави м'яти.Kinetics of bitter matters in aquatic solution of hope extract in speed-up terms with different concentration of antioxidants from the digister are investigated. Certainly effective concentration of antioxidants from the bark oak, st-john's-wort herbares and mint herbares are determinated