Amorphous Silica Containers for Germanium Ultrapurification by Zone Refining

We have studied the wetting behavior of molten germanium on silica ceramics and amorphous silica coatings in vacuum at a pressure of 1 Pa and a temperature of 1273 K. The results demonstrate that the wetting of rough surfaces of ceramic samples and coatings by liquid Ge is significantly poorer than that of the smooth surface of quartz glass. The contact angle of polished glass is ~100°, and that of the ceramics and coatings increases from 112° to 137° as the total impurity content of the material decreases from 0.120 to 1 × 10–3 wt %. Using experimental contact angle data, we calculated the work of adhesion of molten Ge to the materials studied. Its value for the surface of the ceramics and coatings decreases from 0.45 to 0.20 J/m2 with decreasing impurity content, whereas the work of adhesion to a smooth glass surface is 0.55 J/m2. We have fabricated fused silica test containers coated with high-purity amorphous silica. Using horizontal zone refining, we obtained germanium samples with a carrier concentration difference on the order of 1011 cm–3

STREPTOCOCCUS AGALACTIAE CARRIAGE RATE AMONG WOMEN OF CHILDBEARING AGE AND ITS ROLE IN THE DEVELOPMENT OF CONGENITAL INFECTIONS: PRELIMINARY RESULTS OF A PILOT STUDY

Tracheobronchial aspirate samples for PCR were obtained from 78 newborns with intrauterine pneumonia to verify the disease etiology. It was found that in 11.5% of cases congenital pneumonia was caused by Streptococcus agalactiae (S. agalactiae).  PCR test of pap smears obtained from 401 women (aged from 17 to 35 years) found the genome of S. agalactiae in 19.5% of cases. In 31 of the 78 infected women (39.7%), carriage of S. agalactiae was asymptomatic, characterized by the absence of complaints or any clinical or laboratory manifestations of the inflammatory process. The high S. agalactiae infection level in reproductiveage women and its role in the etiology of congenital infection determines the need for compulsory screening of pregnant women for S. agalactiae and antibiotic prophylaxis of perinatal S. agalactiae infection

Amorphous Silica Containers for Germanium Ultrapurification by Zone Refining

We have studied the wetting behavior of molten germanium on silica ceramics and amorphous silica coatings in vacuum at a pressure of 1 Pa and a temperature of 1273 K. The results demonstrate that the wetting of rough surfaces of ceramic samples and coatings by liquid Ge is significantly poorer than that of the smooth surface of quartz glass. The contact angle of polished glass is ~100°, and that of the ceramics and coatings increases from 112° to 137° as the total impurity content of the material decreases from 0.120 to 1 × 10–3 wt %. Using experimental contact angle data, we calculated the work of adhesion of molten Ge to the materials studied. Its value for the surface of the ceramics and coatings decreases from 0.45 to 0.20 J/m2 with decreasing impurity content, whereas the work of adhesion to a smooth glass surface is 0.55 J/m2. We have fabricated fused silica test containers coated with high-purity amorphous silica. Using horizontal zone refining, we obtained germanium samples with a carrier concentration difference on the order of 1011 cm–3

Causal treatment of congenital cytomegalovirus infection: current achievements and routine practice

The key factor for the effective treatment of infectious diseases is timely causal treatment [1, 2]. However, due to various reasons, the arsenal of etiotropic drugs for the treatment of congenital infections (CIs) has been significantly small [3–6]. At the same time, in the treatment of bacterial CIs (congenital syphilis, congenital listeriosis, congenital Streptococcus agalactiae infection, congenital chlamydiosis, congenital ureaplasmosis, congenitan mycoplasmosis and other), only some of the effective antibiotics are not safe enough for use in newborns. What is more, until recently, there were practically no etiotropic therapies except Aciclovir for the treatment of viral CIs [2–6]. In view of the fact that cytomegalovirus infection (CMV) is the most common viral CI (in the US, it is diagnosed in 1% of all live births), the absence of etiotropic therapies has been particularly critical for the management of congenital CMV infection [2]

The Interaction of the Gas Phase with the Germanium Melt in the Process of Crystals Growth

Проведен термодинамический анализ взаимодействия газовой фазы с расплавом в ходе выращивания монокристаллов германия. Рассмотрены процессы роста кристаллов в среде инертного газа и кристаллизации Ge в среде водорода. Установлена взаимосвязь концентрации кислорода в слитках полупроводникового германия с парциальным давлением кислорода в инертном газе и парциальным давлением водяного пара в водороде. Предложена термодинамическая модель взаимодействия кислорода и влаги в газовой среде с расплавом германияA thermodynamic analysis of the interaction of the gas phase with the germanium melt during of crystal growth was carried out. The processes of crystal growth in inert gas and crystallization of germanium in a hydrogen atmosphere was considered. Quantitative relationship of oxygen concentration in the semiconductor Ge with a of an inert gas and in hydrogen has been established. A thermodynamic model of the interaction of the gas phase with the germanium melt in the process of crystals growth was create

Dissolution of Oxygen in Germanium in the Process of Crystals Growth

Методом ИК-Фурье спектрометрии определено содержание кислорода в монокристаллах германия, выращенных по методу Чохральского. Проведен термодинамический анализ процесса растворения в Ge остаточного кислорода, содержащегося в газовой фазе.The oxygen content of germanium single crystals grown by the Czochralski method has been determined by the method of Fourier-transform infrared spectroscopy. A thermodynamic analysis of the dissolution process of oxygen in germanium during of crystal growth was carried out