Методом просвечивающей электронной микроскопии (ПЭМ) высокого разрешения изучены структурные изменения в сплаве Cu-37 Zn (масс.%) после двухсторонней пескоструйной поверхностной обработки (ППО). Ус-тановлено, что в приповерхностных слоях этого сплава с низкой энергией дефекта упаковки и ближним порядком образуется нанокристаллическая (НК) структура. Приведены параметры, характеризующие изменение размеров НК-зерен и полигональных структур. Обсуждена роль множест-венного двойникования (микродвойникования) в измельчении зеренной структуры сплава.Методою ПЕМ високої роздільчої здатности вивчено структурні зміни в стопі Cu-37 Zn (мас.%) після двосторонньої піскоструминного поверхне-вого оброблення (ППО). Встановлено, що в приповерхневих шарах цього стопу з низькою енергією дефекту паковання та близьким порядком утво-рюється нанокристалічна (НК) структура. Наведено параметри, які хара-ктеризують зміни розмірів НК-зерен та полігональних структур. Обгово-рено роль багатовимірного двійникування (мікродвійникування) у подрі-бненні зернуватої структури стопу.The structural changes in a Cu-37 Zn (wt.%) alloy after bilateral surface sandblasting is studied by TEM. As revealed in near-surface layers of this alloy with low stacking-faults energy and short-range order, the nanocrystalline structure is formed. The parameters characterizing a change of the sizes of nanograins and polygonal structures are presented. The role of the manydimensional twinning (microtwinning) in milling grain structure of an alloy is discussed.Ключевые слова: ПЭМ, поверхностная обработка, зерна, двойники, ближний порядок, дефекты упаковки.
The article describes the synthesis of ammonium salts of maleamic acids containing amino acid fragments. At the first stage, the interaction of maleic anhydride with aliphatic and aromatic amino acids yielded the corresponding maleamic acids. Glycine, α-alanine, ε-aminocaproic, para-aminosalicylic, ortho-, meta- and para-aminobenzoic acids were used as amino acids. In the case of aliphatic amino acids, the process was carried out in an aqueous or aqueous-acetone (2: 1) medium. For aromatic amino acids, acetone was used as a solvent. As weakly exothermic reactions progressed, colorless finely crystalline or light yellow friable precipitates of the corresponding maleamic acids precipitated. In the second stage, the suspension of synthesized maleamic acids in an aqueous medium was treated with a calculated amount of 25% aqueous ammonia solution. With further isothermal evaporation of aqueous solutions, ammonium salts crystallize in the form of hygroscopic colorless prisms or fine crystalline dense precipitates. The structure of the newly obtained compounds was confirmed by IR and 1H NMR spectroscopy. In order to identify the biological activity of the synthesized salts, the effect of their aqueous solutions of various concentrations on the germination energy (GE) and laboratory germination (LG) of the seeds of spring barley cultivar «Elf», winter rye of the «Bezenchukskaya 87» variety and wheat was studied spring varieties «Moskovskaya 35». The determination of GE and LG drug in experimental and control samples showed that 0.01% - 0.001% aqueous solutions have a stimulating effect on seed germination compared to control. The best effect is achieved with pre-sowing seed treatment with 0.01% aqueous solutions of ammonium salts of maleic acids, which allows to increase germination by 9-26%.
The paper provides data on an improved method for the synthesis of 2-phenylethenylphosphonic acid dichloride by interacting of carbamide derivatives with 2-phenylethenyltrichlorophosphonium hexachloro-phosphate, which is an intermediate adduct of the reaction of styrene and phosphorus pentachloride. Readily available urea, biuret, and acetylurea have been used as transformers of the adduct. It has been shown that carbamide derivatives are not only donors of the oxygen atom, but they also bind hydrogen chloride released at the stage of complexation into the corresponding hydrochlorides. This allows obtaining the target 2-phenyl-ethenyldichlorophosphonate without admixture of the hydrochlorination by-product. The phenomenon of induced fluorescence of 2-phenylethenylphosphonic acid and its esters in the solid phase and in solution was revealed. The growth-regulating activity of 2-phenylethenylphosphonic acid and O,O-di(p-nitrophenyl)-2-phenylethenyl-phosphonate on the seed germination energy, laboratory and field germinations of grain and vegetable crops was established. It is shown that pre-sowing treatment of the Prokhorovka spring wheat seeds with a 0.0005% aqueous solution of O,O-di(p-nitrophenyl)-2-phenylethenylphosphonate leads to an increase in wheat yield by 21%, which expands the range of products for this purpose. A study of the acute toxicity of 2-phenylethenylphosphonic acid according to LeBlanc on male rats kept on a standard vivarium diet showed that it has a two-phase effect. In the first phase, there are symptoms of damage to the motor part of the peripheral nervous system in the form of local seizures and the central nervous system in the form of the general suppression of motor activity and moderate relaxation of skeletal muscles, and in the second phase, the acid manifests itself in a general toxic effect. Determination of the LD50 of 2-phenylethenylphosphonic acid showed that it belongs to the third class of toxicity – low-hazard substances.
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