Humic acids in bottom sediments of the Western Pacific

Elemental composition, functional groups, and molecular mass distribution were determined in humic acids from the Western Pacific abyssal and coastal bottom sediments. Humic acid structure was studied by oxidative degradation with alkaline nitrobenzene and potassium permanganate, p-coumaric, guaiacilic, and syringilic structural units typical for lignin of terrestrial plants were identified in humic acids by chromatographic analysis of oxidation products. Polysubstituted and polycondensed aromatic systems with minor proportion of aliphatic structures were basic structural units of humic acids in abyssal sediments.

(Table 2) Trace element contents in ancient Black Sea sapropelic muds

The study of vertical distribution of Mo, V, Co, Ni, and Cu in mass of Black Sea sediments showed that maximum concentrations occur in sapropelic muds of ancient Black Sea deposits. A special study of sapropels samples showed a sufficiently clear correlation of Cu, Ni, Mo, and V contents with organic carbon contents; Co contents do not show such a correlation, but show one with contents of pyrite sulfur. A study of fractions of bitumen, free humic and fulvic acids showed that some part of metal contents in the sediments is bound with organic matter. It is shown that increased concentrations of trace elements in sapropels result from removing of dissolved metals from seawater by organic detritus during deposition on the bottom, in vivo concentration of metals in plankton organisms is of secondary importance.

An algorithm for the solution of a quadratic equation using continued fractions /

Thesis (M. S.)--University of Illinois at Urbana-Champaign, 1972.

Further negative results regarding the use of continued fractions for digital computer arithmetic /

Mode of access: Internet.

On a negative result regarding the use of continued fractions for digital computer arithmetic /

Includes bibliographical references.

The status of investigations into the use of continued fractions for computer hardware /

Bibliography: p. 29.

A method for solving polynomial equations by continued fractions.

Bibliography: p. 16.

Application of continued fractions for fast evaluation of certain functions on a digital computer.

Bibliography: p. 23.

Nouveau traité d'arithmétique décimale : contenant toutes les opérations ordinaires du calcul, les fractions, l'extraction de racines, le système métrique ... /

Mathieu Bransiet, en religion Frère Philippe.

The builder's complete assistant, or, A library of arts and sciences, absolutely necessary to be understood by builders and workmen in general : viz. I. Arithmetick, vulgar and decimal, in whole numbers and fractions. II. Geometry, lineal, superficial, and solid. III. Architecture, universal. IV. Mensuration. V. Plain trigonometry. VI. Surveying of land, &c. VII. Mechanick powers. VIII. Hydrostaticks : illustrated by above thirteen hundred examples of lines, superficies, solids, mouldings, pedestals, columns, pilasters, entablatures, pediments, imposts, block cornices, rustick quoins, frontispieces, arcades, porticos, &c. : proportioned by modules and minutes, according to Andrea Palladio, and by equal parts : likewise great varieties of trussed roofs, timber bridges, centerings, arches, groins, twisted rails, compartments, obelisks, vases, pedestals for bustos, sun-dials, fonts, &c. and methods for raising heavy bodies by the force of levers, pulleys, axes in peritrochio, screws, and wedges, as also water, by the common pump, crane, etc. : wherein the properties, and pressure of the air on water, &c. are explained : the whole exemplified by 77 large quarto copper-plates /

All of the numbered plates in the atlas are double plates, and thus are counted twice in the adjusted plate count.

How to teach fractions to young children. Lessons for the first four years,

Mode of access: Internet.

Mathematics for the practical engineer. Engineers' study course from Power; a mathematical manual for the power plant engineer. Contains simplified lessons for home-study in fractions, ratio and proportion, percentage, involution and evolution, square root, cube root, formulas, logarithms, mensuration and plane trigonometry,

Mode of access: Internet.

The five orders of architecture : containing the most plain and simple rules for drawing and executing them in the purest style, for the use of workmen : exhibiting the most approved modes of applying each in practice, suitably to the climate of Great Britain ; including an historical description of Gothic architecture, illustrated with specimens selected from the most celebrated structures now existing, and numerous plans, elevations, sections, and details of various buildings executed by architects of great eminence : to which are added treatises on projection, perspective, fractions, decimal arithmetic, &c. ...

Includes index.

Abundance of trace and minor elements in organic and mineral fractions of coal /

"August 1980."