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The scientific article presents the results of a scientific experiment conducted to study the quality indicators of beef obtained from interbreeding of cattle of meat, dairy and combined breeds in the conditions of the Volgograd agricultural enterprise JSC \"Berdievsky Elevator\". The resulting crossbred bulls at the age of 9 months were divided into 4 groups of 10 heads each according to the principle of pairs of analogues: I experimental group of ½ crossbreed (Kazakh white-headed x Russian brown), II experimental group of ½ crossbreed (Kazakh white-headed x Aberdeen-Angus), III experimental group of ½ crossbreed (Aberdeen-Angus x red steppe), IV experimental group of ½ crossbreed (Simmental x red-mottled). The formed groups of animals were put on fattening up to 16 months of age. The growth dynamics of bulls and the qualitative characteristics of beef were evaluated.

The experimental study is aimed at elucidation the laws of Au sorption/deposition by various natural sorbents in an acidic environment (pH=2). The experiments simulated the conditions of the dispersion train of the Ursk tailings (Kemerovo region, Russia), where active concentration of Au by natural organic matter in an acidic environment is observed. It was found that the degree of extraction of gold from a sulfate solution is generally higher than from chloride solution. This may indicate higher thermodynamic stability of Au chloride complexes in an acidic environment than sulfate ones. Higher deposition rates of gold are observed in solutions with a predominant content of sulfate ions. According to the degree of deposition of Au, a series was established (from larger to smaller): a mixture of clay minerals (smectite + palygorskite + muscovite) > humic acids > kaolinite

The paper presents the results of determination of the ore contents of rare earth elements (REE) in geological samples by atomic emission spectrometry with arc two-jet plasmatron, which allows to analyze solid-phase samples asa fine powders. We studied a niobium-rare earth ore sampled at the Buranniy site of the Tomtor deposit (Arctic Siberia, Russia). The results for all REEs, except for Tb, Yb and Lu, are consistent with the ICP-MS data. It is shown that the use of several analytical lines at the same time in the determination of REE significantly increases the determination accuracy and reliability of the results

Influence of sample pretreatment on the analysis of the high contents of rare earth (REE) and high field strength (HFSE) elements in geological samples by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) was studied. The rocks and rich ores of the Tomtor Nb-REE deposit were explored. Complete dissolution of the geological samples with a high content of “refractory” minerals has been achieved using fusion with a sodium peroxide. The results obtained by ICP-AES and ICP-MS after chemical dissolution are comparable with the results obtained by the XRF-SR without chemical pretreatment

A feature of the Tomtor Nb-REE deposit is the extremely low δ13C‰ values in carbonates, which is usually associated with the participation of biogenic/methanogenic processes. In addition, the δ13C value measured for a portion of CO2 released within 1 hour during the interaction of some samples with H3PO4 differs significantly from the portion released within 24 hours and 7 days. The purpose of the study was to determine the stability of carbon-containing minerals when leached with H3PO4 at a temperature of 70 °C for 1 hour and 24 hours. In the initial substance, solutions and residues, the content of elements (Ca, Mg, Mn, Fe, Sr, Ba, REE, A1) was analyzed, characterizing minerals that contain or may contain CO32-: carbonates, minerals of the crandallite group and apatite. It has been established that carbonates of hydrothermal and supergene origin from rocks and ores of the Tomtor complex, regardless of composition, dissolve in orthophosphoric acid (H3PO4) by 85-95 % in the first hour and completely within 24 hours. Minerals of the crandallite group, depending on the form of isolation, dissolve by 7-70 % in the first hour, and by 30-87 % in 24 hours. Fine-grained apatite dissolves completely or almost completely in the first hour.

В работе приведены результаты определения рудных содержаний редкоземельных элементов (РЗЭ) в геологических образцах методом атомно-эмиссионной спектрометрии с дуговым двухструйным плазматроном, позволяющей проводить анализ твердофазных образцов в виде мелкодисперсных порошков. Изучался образец ниобий-редкоземельной руды, отобранный на участке Буранный Томторского месторождения (Арктическая Сибирь, Россия). Результаты анализа по всем РЗЭ, за исключением Tb, Ybи Lu, согласуются с данными ИСП-МС-анализа. Показано, что использование одновременно нескольких аналитических линий при определении РЗЭ значительно повышает точность определения и достоверность результатов.

Аннотация. В работе изучено влияние химической пробоподготовки на определение высоких содержаний редкоземельных (РЗЭ) и высокозарядных (ВЗЭ) элементов в геологических образцах методами атомно-эмиссионной спектрометрии с индуктивно-связанной плазмой (ИСП-АЭС) и масс-спектрометрии с индуктивно-связанной плазмой (ИСП-МС). Изучались породы и богатые руды Томторского ниобий-редкоземельного месторождения. Предложена методика сплавления с пероксидом натрия геологических образцов с высоким содержанием «упорных» минералов, при котором достигается полное вскрытие пробы. Результаты анализа методами ИСП-АЭС и ИСП-МС с химической пробоподготовкой сопоставлены с результатами, полученными методом РФА-СИ без химической пробоподготовки.

The experimental study is aimed at elucidation the laws of Au sorption/deposition by various natural sorbents in an acidic environment (pH=2). The experiments simulated the conditions of the dispersion train of the Ursk tailings (Kemerovo region, Russia), where active concentration of Au by natural organic matter in an acidic environment is observed. It was found that the degree of extraction of gold from a sulfate solution is generally higher than from chloride solution. This may indicate higher thermodynamic stability of Au chloride complexes in an acidic environment than sulfate ones. Higher deposition rates of gold are observed in solutions with a predominant content ofsulfate ions. According to the degree of deposition of Au, a series was established (from larger to smaller): a mixture of clay minerals (smectite + palygorskite + muscovite) > humic acids > kaolinite.