These researches have been made in order to improve the mechanical properties of a Chromium�Molybdenum alloyed steel non-conventionally treated in a magnetic field. Through the thermo-magnetic treatments, applied before thermo-chemical treatment, the mechanical properties of this material have been improved, especially in the case of a great content of chromium. The hardness values of the superficial layers which have been obtained after a complex system of thermo-magnetic treatments followed by a thermo-chemical treatment, the superficial layers content and the behaviour of the steel at the wear through dry friction tests were used as criterion. The paper is a review of the researches from the last few years.
This article presents an integrated approach for the authentication of five Russian icons through the study of their paint materials (elemental composition and stratigraphic mapping), state of conservation and artistic technique. The results of the applied analytical protocol, involving optical and scanning electron microscopy coupled with energy-dispersive X-ray spectrometry and Fourier transformed infrared spectroscopy/microspectroscopy, led to the conclusion that the five icons belong to the same group and iconographic school (from Northern Russia) and date from the end of the 16th century to the beginning of 17th century. Because of massive overpainting, the icons ''suffered'' a change in iconographic style and significance, and restoration treatment brought to light the original painting and its attribution. Identification of the composition of the original chromatic palette used by the iconographer, the stratigraphic mapping and the conservation state of the painting materials, along with the features of the original artistic technique, furnished key elements for the icons' authentication. Here, we present the first experimental data concerning the identification of the authentication characteristics, being part of a large project that has as its final aim the evaluation of the effectiveness and effects of the cleaning agent on the paint layers. Microsc. Res. Tech. 72:755-765, 2009. V
The purpose of this research have been to determine the influence of soil fertilizations systems (fertilization with: nitrogen, phosphorous, nitrogen and phosphorous, farmyard manure) on the physical properties (penetration hardness) and chemical properties (humidity, metals) of the soil. The experiments have been carried out in the experimental field of National Agricultural Research and Development Institute -Fundulea, Romania, for a wheat monoculture. The lowest values of the metal content in soil (nickel, copper, zinc, arsenic, lead) have been recorded for wheat experimental variant -fertilized with N90P75 kg/ha (a1b4), and the highest content have been recorded for manganese (766 mg/kg dry matter), and for the wheat experimental variant a1b4, respectively (wheat-fertilized with N90P75 kg/ha active matter), working depth 0-15 cm.
The conversion of n-heptanes into aromatic hydrocarbons benzene, toluene and xylenes (BTX), by the chromatographic pulse method in the temperature range of 673 - 823K was performed over the HZSM-5 and Ag-HZSM-5 zeolites modified by ion exchange with AgNO3 aqueous solutions. The catalysts, HZSM-5 (SiO2/Al2O3 = 33.9), and Ag-HZSM-5 (Ag1-HZSM-5 wt. % Ag1.02, Ag2-HZSM-5 wt. % Ag 1.62; and Ag3-HZSM-5 wt. % Ag 2.05 having different acid strength distribution exhibit a conversion and a yield of aromatics depending on temperature and metal content. The yield of aromatic hydrocarbons BTX appreciably increased by incorporating silver cations Ag+ into HZSM-5.
Water resources in the Jijia catchment basin are limited and often polluted. The catchment basin of Jijia is situated in northeastern Romania and it crosses the Moldavian Plain on the north-west-south-east direction. The purpose of the present study is to analyze 26 physico-chemical parameters providing the annual and multiannual water quality index. Two water-sampling points were selected: Jijia-Victoria [S.1] and Jijia-Opriseni [S.2]. The high values of nitrates are caused by the use of nitrogen-based chemical fertilizers and of manure. Contamination with nitrites (N-NO2-) and nitrates (N-NO3-) of wetlands and deepwater habitats in the floodplain of Jijia is still high because of agricultural and zootechnical activities. The phosphorus within freshwater habitats is a consequence of anthropogenic pressure: improper storage of animal waste and/or use of phosphates-based fertilizers. Global water quality index (WQi) shows that both monitoring stations are included in the Medium high class.
The purpose of this research has been to determine the influence of soil fertilizations systems (fertilization with: nitrogen, phosphorous, nitrogen and phosphorous, farmyard manure) on the chemical properties (pH, humus, aluminium and phosphorous content) of the soil. The experiments have been carried out in the experimental field of National Agricultural Research and Development Institute � Fundulea, Romania, for: wheat monoculture, 2-year crop rotation (wheat-corn), 3-year crop rotation (wheat-pea-corn), and 4-year crop rotation wheat-sun-flower-pea-corn. The lowest values of the phosphorous content in soil have been recorded for 3-year experimental variant (wheat-pea-corn), unfertilized (a3b1), and the lowest aluminium content in soil 596 mg/kg d.m.) has been recorded for the a4b5 experimental variant (4-year crop rotation wheat-sunflower-pea-corn) � fertilized with N90P75 kg/ha a.m., working depth: 15-30 cm.
This is the second paper belonging to a study concerning the authentication of ancient easel-paintings, on canvas and wood support, from private and public collections, by using the FT-IR spectrophotometry technique for the analysis of the painting materials. Different pigments, egg binders, caseins and animal glue, often found in ancient easel-paintings on wood or canvas, have been used as standards for establishing the ageing rate of the paintings by correlation with the dates presented in the first note. The determination of the degradation rate of the painting materials is an important archaeometric characteristic used in authentication.
scite is a Brooklyn-based startup that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.