Thermochemistry of Al-Si-Fe(Co, Ni) Ternary Melts

The thermochemical properties of Al-Co-Si liquid alloys remain unexplored. Therefore, to estimate the interaction characteristics of liquid Al-Co-Si alloys we have simulated the mixing enthalpies, using the regular approximation and applying "geometric" model by Bonnier-Caboz

Fragments of Isothermal Sections of the Gd-Ge(Si)-Ga Systems Phase Diagrams at 800 ºC

The Gd-rich alloys of the Gd-Ge(Si)-Ga systems have been studied by the X-ray powder diffraction. The parts of the isothermal sections of these systems (800 0C, up to 33.3 at. % Gd) have been constructed. Four ternary compounds were found to exist here, namely, 1-GdGe1.0-0.7Ga1.0-1.3 (a-ThSi2-type structure), 2-Gd11Ge9Ga1 (Ho11Ga10), 1-GdSi0.9-0.6Ga1.1-1.4 (a-ThSi2) and 2-GdSi0.9-0.6Ga0.1-0.4 (CrB). One of these compounds (2-Gd11Ge9Ga1) is in fact the Ga-stabilized solid solution on the base of the high temperature Gd11Ge10 compound. Extended solid solutions on the base of the most Gd-{Si,Ge,Ga} binary compounds was shown to form in the Gd-Ge(Si)-Ga systems

Geographical Distribution, Incidence, Malignancies, and Outcome of 136 Eastern Slavic Patients With Nijmegen Breakage Syndrome and NBN Founder Variant c.657_661del5

Nijmegen breakage syndrome (NBS) is a DNA repair disorder characterized by combined immunodeficiency and a high predisposition to lymphoid malignancies. The majority of NBS patients are identified with a homozygous five base pair deletion in the Nibrin (NBN) gene (c.657_661del5, p.K219fsX19) with a founder effect observed in Caucasian European populations, especially of Slavic origin. We present here an analysis of a cohort of 136 NBS patients of Eastern Slav origin across Belarus, Ukraine, Russia, and Latvia with a focus on understanding the geographic distribution, incidence of malignancy, and treatment outcomes of this cohort. Our analysis shows that Belarus had the highest prevalence of NBS (2.3 per 1,000,000), followed by Ukraine (1.3 per 1,000,000), and Russia (0.7 per 1,000,000). Of note, the highest concentration of NBS cases was observed in the western regions of Belarus and Ukraine, where NBS prevalence exceeds 20 cases per 1,000,000 people, suggesting the presence of an “Eastern Slavic NBS hot spot.” The median age at diagnosis of this cohort ranged from 4 to 5 years, and delay in diagnosis was more pervasive in smaller cities and rural regions. A total of 62 (45%) patients developed malignancies, more commonly in males than females (55.2 vs. 34.2%; p=0.017). In 27 patients, NBS was diagnosed following the onset of malignancies (mean age: 8 years). Malignancies were mostly of lymphoid origin and predominantly non-Hodgkin lymphoma (NHL) (n=42, 68%); 38% of patients had diffuse large B-cell lymphoma. The 20-year overall survival rate of patients with malignancy was 24%. However, females with cancer experienced poorer event-free survival rates than males (16.6% vs. 46.8%, p=0.036). Of 136 NBS patients, 13 underwent hematopoietic stem cell transplantation (HSCT) with an overall survival of 3.5 years following treatment (range: 1 to 14 years). Indications for HSCT included malignancy (n=7) and immunodeficiency (n=6). Overall, 9% of patients in this cohort reached adulthood. Adult survivors reported diminished quality of life with significant physical and cognitive impairments. Our study highlights the need to improve timely diagnosis and clinical management of NBS among Eastern Slavs. Genetic counseling and screening should be offered to individuals with a family history of NBS, especially in hot spot regions. © Copyright © 2021 Sharapova, Pashchenko, Bondarenko, Vakhlyarskaya, Prokofjeva, Fedorova, Savchak, Mareika, Valiev, Popa, Tuzankina, Vlasova, Sakovich, Polyakova, Rumiantseva, Naumchik, Kulyova, Aleshkevich, Golovataya, Minakovskaya, Belevtsev, Latysheva, Latysheva, Beznoshchenko, Akopyan, Makukh, Kozlova, Varabyou, Ballow, Ong, Walter, Kondratenko, Kostyuchenko and Aleinikova.We thank all doctors for clinical help for patients. We also appreciate the support of patient and their parents for agreeing to take part in this study. TP thanks Sergey?Nikulshin, Marika Grutupa, and Zanna Kovalova. We thank Joseph Dasso for editing this manuscript, primarily for proper English

Особливості впливу модифікування на структуру та властивості ливарних алюмінієвих сплавів

Raising of problem. The purpose of this work is studying of features of structure and properties of the foundry aluminum alloys processed by nanodisperse modifiers. The analysi of the existing modifiers of aluminum alloys of Al−Si system is carried out. On the basis of the classical theory of modifying the type of the refractory modifier – carbide silicon as SiC of particles in size 50...100 nanometers it was offered. The technology of input of the modifier in fusion is developed. It is carried out industrial experiences of melting of an aluminum alloy AL4, AL4S. Scientific novelty. Criteria of a choice of the nanodispersive SiC modifier are established. Thermotemporary parameters of modifying are laid. The effect of crushing of dendrit’s structure of the modified alloys is received. The uniform fine-grained structure of castings from the modified AL4 alloy is reached. Technological properties the industrial aluminum alloys are increased, mechanical properties is reduced.Постановка проблемы. В данное время актуальным является изучение особенностей структуры и свойств литейных алюминиевых сплавов, обработаных нанодисперсными модификаторами. Проведен анализ существующих модификаторов алюминиевых сплавов системы Al−Si. На основе классической теории модифицирования выбран тип тугоплавкого модификатора − порошок карбида кремния SiС размером частиц 50...100 нм. Разработана технология ввода модификатора в расплав. Проведены опытно-промышленные плавки алюминиевого сплава АЛ4, АЛ4С. Научная новизна. Установлены критерии выбора нанодисперсного модификатора SiС. Проложены термовременные параметры модифицирования. Получен эффект измельчения дендритной структуры модифицированных сплавов. Достигнута однородная мелкозернистая структура отливок из модифицируемого сплава АЛ4. Повышены технологические и механические свойства промышленных алюминиевых сплавов, снижена газонасыщеность. Постановка проблеми. Наразі актуальним стає вивчення особливостей структури та властивостей ливарних алюмінієвих сплавів, оброблених нанодисперсними модифікаторами. Проведено аналіз існуючих модифікаторів алюмінієвих сплавів системи Al−Si. На основі класичної теорії модифікування обрано тип тугоплавкого модифікатора – порошок карбіду кремнію SiС розміром частинок 50...100 нм. Розроблено технологію введення модифікатора в розплав. Проведено дослідно-промислові плавки алюмінієвих сплавів АЛ4, АЛ4С. Наукова новизна. Встановлено критерії вибору нанодисперсного модифікатора SiС. Наведено термічно-часові параметри модифікування та ефект зміни дендритної структури модифікованих сплавів. Досягнуто однорідну дрібнозернисту структуру виливків та модифікованого сплаву АЛ4. Підвищено технологічні  властивості  промислових алюмінієвих сплавів, знижено газонасиченість, механічні властивості.