Abstract Stability and structure of complexes between silver (I) l -methionine (L) deduced from potentiometric 1 H NMR measurements allow to assume the prevailing several protonated species. The experimental data are compatible with formation following complexes: AgL, AgL 2 , AgH L, L 3 4 . coordination sites obtained by spectra, showing that only bond methylthioether sulfur atom is responsible...

The work presents the design and fabrication procedures used to manufacture inexpensive iron-base powders employed as a matrix in diamond-impregnated tool components. Three newly developed low alloy steel powders, containing from 94.4 99.4 wt.% Fe, have been formulated with assistance of ThermoCalc software produced by means proprietary process patented AGH-UST. It has shown that are readily pr...

gorganrood river is one of the three main rivers in golestan province have a basic role in golestan water supply. to study gorganrood water quality and estimating maximum allowable pollutant, water quality data was used from 8 stations. purification of this river has been studied by two methods: statistical and experimental methods. each method showed that the gorganrood river at present condit...

The yielding arch support is transported and installed in the face with use of auxiliary machines. These activities underground mining cause many problems, which have as yet not been solved. Currently, transport assembly are carried out manually, using roadheader suspended rail, or various types mounting platforms. analysis structure existing solutions resulted development an original that met ...

Longwall shearers’ haulage system of the Eicotrack type, used most often nowadays, is presented in this article. Its disadvantages, causing problems with a correct operation mechanized longwall shearer systems, are discussed. The concept innovative Flextrack, which should reduce occurrence disadvantages mentioned above, described. A course and research results, connected rig tests Flextrack fun...

For the microbiostratigraphical studies, a stratigraphical section (named Dareh-Goshayesh) has been selected in southeast of Maragheh, Northwestern Iran. The thickness of successions in the selected stratigraphic section is measured about 223.6 m. The mentioned studied stratigraphic section is composed of two clastic and carbonate units. This succession unconformably overlies the Lar Formation ...

introduction: climate change is one of the most significant challenges in sustainable development that has negative effects on land and marine ecosystems. this phenomenon leads to imbalances that cause effects including hydrological changes, increased soil erosion, increased runoffs and reduced groundwater aquifer feeding, etc. effects of climate changes over the past decade have significantly ...