Production of chemically resistant refractory concrete mix from metallurgical waste and their physical and chemical properties

The research findings of physical and chemical properties of heavy and light concretes, contaminated with water suspension of mold fungi spores, are presented. It is noted that the concretes’ funginertness (resistance to fungi) is significantly influenced by their age, porosity and the alkalinity of medium. In the course of time the strength of concrete decreases, which is conditioned by the activation of mold fungi growth processes, as a result of de-alkalization of concrete, due to carbonization of cement stone and release of organic acids into the material. To improve the concrete’s resistance in biologically aggressive media, it is suggested to modify concrete with a new poly-functional fungicidal modifier, obtained on the basis of resorcine production waste. It has been demonstrated that the addition of resorcinol-formaldehyde oligomers to concrete mix completely inhibits mold fungi growth and allows obtaining concretes with the increased density and strength, which can be used in conditions of biologically aggressive media. The strength characteristics of the cement stone with the researched modifiers are not reduced at mold fungi spores’ contamination, but, on the contrary, slightly increase, due to the increase of cement paste fluidity, decrease of W/C ratio, reduction of micro-cracks in concrete and compaction of its structure, due to the peptizing action of the modifier.

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Statistical criteria of stellar population types

Symposium - International Astronomical Union ◽

10.1017/s0074180900053304 ◽

1966 ◽

Vol 24 ◽

pp. 101-110

Author(s):

W. Iwanowska

Keyword(s):

Stellar Population ◽

Chemical Properties ◽

Spectrophotometric Study ◽

Physical And Chemical Properties ◽

Population Type ◽

The Galaxy ◽

Distribution Parameters ◽

Physical And Chemical ◽

Statistical Criteria ◽

And Chemical Properties

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

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Only one sugar offers you such a variety of important physical and chemical properties

Chemical & Engineering News ◽

10.1021/cen-v037n007.p004 ◽

1959 ◽

Vol 37 (7) ◽

pp. 4

Keyword(s):

Chemical Properties ◽

Physical And Chemical Properties ◽

Physical And Chemical ◽

And Chemical Properties

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Response of corn (Zea mays L.) to various organic-based fertilizers in marginal upland of Sta. Rita, Samar

Annals of Tropical Research ◽

10.32945/atr39sa3.2017 ◽

2017 ◽

pp. 31-43

Author(s):

Berta Ratilla ◽

Loreme Cagande ◽

Othello Capuno

Keyword(s):

Block Design ◽

Management Strategies ◽

Chemical Properties ◽

Organic Fertilizers ◽

Growth And Yield ◽

Physical And Chemical Properties ◽

Total N ◽

Randomized Complete Block Design ◽

Physical And Chemical ◽

And Chemical Properties

Organic farming is one of the management strategies that improve productivity of marginal uplands. The study aimed to: (1) evaluate effects of various organic-based fertilizers on the growth and yield of corn; (2) determine the appropriate combination for optimum yield; and (3) assess changes on the soil physical and chemical properties. Experiment was laid out in Randomized Complete Block Design, with 3 replications and 7 treatments, namely; T0=(0-0-0); T1=1t ha-1 Evans + 45-30-30kg N, P2O5, K2O ha-1; T2=t ha-1 Wellgrow + 45-30-30kg N, P2O5, K2O ha-1; T3=15t ha-1 chicken dung; T4=10t ha-1 chicken dung + 45-30-30kg N, P2O5, K2O ha-1; T5=15t ha-1 Vermicast; and T6=10t ha-1 Vermicast + 45-30-30kg N, P2O5, K2O ha-1. Application of organic-based fertilizers with or without inorganic fertilizers promoted growth of corn than the control. But due to high infestation of corn silk beetle(Monolepta bifasciata Horns), its grain yield was greatly affected. In the second cropping, except for Evans, any of these fertilizers applied alone or combined with 45-30-30kg N, P2O5, K2O ha-1 appeared appropriate in increasing corn earyield. Soil physical and chemical properties changed with addition of organic fertilizers. While bulk density decreased irrespective of treatments, pH, total N, available P and exchangeable K generally increased more with chicken dung application.

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