AlGaAs/GaAs photovoltaic converters for high power narrowband radiation

AlGaAs/GaAs-based laser power PV converters intended for operation with high-power (up to 100 W/cm(2)) radiation were fabricated by LPE and MOCVD techniques. Monochromatic (lambda = 809 nm) conversion efficiency up to 60% was measured at cells with back surface field and low (x = 0.2) Al concentration 'window'. Modules with a voltage of 4 V and the efficiency of 56% were designed and fabricated

High Intensity Low Temperature (HILT) performance of space concentrator GaInP/GaInAs/Ge MJ SCs

In the work, the results of an investigation of GaInP/GaInAs/Ge MJ SCs intended for converting concentrated solar radiation, when operating at low temperatures (down to -190 degrees C) are presented. A kink of the cell I-V characteristic has been observed in the region close to V-oc starting from -20 degrees C at operation under concentrated sunlight. The causes for its occurrence have been analyzed and the reasons for formation of a built-in potential barrier for majority charge carriers at the n-GaInP/n-Ge isotype hetero-interface are discussed. The effect of charge carrier transport in n-GaInP/n-p Ge heterostructures on MJ SC output characteristics at low temperatures has been studied including EL technique

Characterization of the manufacturing processes to grow triple-junction solar cells

A number of important but little-investigated problems connected with III-V/Ge heterostructure in the GaInP/GaInAs/Ge multijunction solar cells grown by MOVPE are considered in the paper. The opportunity for successfully applying the combination of reflectance and reflectance anisotropy spectroscopy in situ methods for investigating III-V structure growth on a Ge substrate has been demonstrated. Photovoltaic properties of the III-V/Ge narrow-band subcell of the triple-junction solar cells have been investigated. It has been shown that there are excess currents in the Ge photovoltaic p-n junctions, and they have the tunneling or thermotunneling character. The values of the diode parameters for these current flow mechanisms have been determined. The potential barrier at the III-V/Ge interface was determined and the origin of this barrier formation during MOVPE heterogrowth was suggested

Monolithic and hybrid integration of InAs/GaAs quantum dot microdisk lasers on silicon

A method of hybrid integration of quantum dot microdisk lasers with silicon wafer is proposed and realized. In addition to the possibility of combining microlasers with various silicon-based electronic and photonic devices, this makes it possible to significantly improve heat removal from the active region of the microlaser. The thermal resistance normalized to the mesa area reaches the level of about 0.002 (K/W)*cm2, which is significantly lower than the corresponding values of QD microlasers on GaAs substrate and monolithically grown on Si. As a result, the threshold current as well as current-induced shift of emission wavelength are reduced in continuous-wave regime

Increasing the quantum efficiency of InAs/GaAs QD arrays for solar cells grown by MOVPE without using strain-balance technology

Research into the formation of InAs quantum dots (QDs) in GaAs using the metalorganic vapor phase epitaxy technique ispresented. This technique is deemed to be cheaper than the more often used and studied molecular beam epitaxy. The bestconditions for obtaining a high photoluminescence response, indicating a good material quality, have been found among awide range of possibilities. Solar cells with an excellent quantum ef?ciency have been obtained, with a sub-bandgapphoto-response of 0.07 mA/cm2per QD layer, the highest achieved so far with the InAs/GaAs system, proving the potentialof this technology to be able to increase the ef?ciency of lattice-matched multi-junction solar cells and contributing to abetter understanding of QD technology toward the achievement of practical intermediate-band solar cells

Preliminary results of determination of chemical element concentrations in the aerosol of Venus clouds

An X-ray radiometeric experiment is described along with the results of measurements of the elemental composition of aerosols in Venusian clouds. A preliminary analysis of the data showed that sulfur is present in the range of heights 63 to 47 km with mean content of 5.8 mg/cu m and that chlorine is present in the height range 61 t0 52 km with a mean content of 4.1 mg/cu m. The results of measurements in the range 52 to 47 km may come to an agreement if phosphorus is present in the aerosol with a mean concentration of 7.7 mg/cu m

Strong anion exchange-mediated phosphoproteomics reveals extensive human non-canonical phosphorylation

Phosphorylation is a key regulator of protein function under (patho)physiological conditions, and defining site‐specific phosphorylation is essential to understand basic and disease biology. In vertebrates, the investigative focus has primarily been on serine, threonine and tyrosine phosphorylation, but mounting evidence suggests that phosphorylation of other “non‐canonical” amino acids also regulates critical aspects of cell biology. However, standard methods of phosphoprotein characterisation are largely unsuitable for the analysis of non‐canonical phosphorylation due to their relative instability under acidic conditions and/or elevated temperature. Consequently, the complete landscape of phosphorylation remains unexplored. Here, we report an u nbiased p hosphopeptide enrichment strategy based on strong a nion ex change (SAX ) chromatography (UPAX ), which permits identification of histidine (His), arginine (Arg), lysine (Lys), aspartate (Asp), glutamate (Glu) and cysteine (Cys) phosphorylation sites on human proteins by mass spectrometry‐based phosphoproteomics. Remarkably, under basal conditions, and having accounted for false site localisation probabilities, the number of unique non‐canonical phosphosites is approximately one‐third of the number of observed canonical phosphosites. Our resource reveals the previously unappreciated diversity of protein phosphorylation in human cells, and opens up avenues for high‐throughput exploration of non‐canonical phosphorylation in all organisms

Роль 3D-моделирования в хирургии поджелудочной железы: обзор

INTRODUCTION: Surgical interventions on the pancreas are technically complex and are accompanied by a fairly large number of complications, which is largely due to the variant anatomy of the pancreas.OBJECTIVE: The aim of this paper is to evaluate the possibilities of 3D modeling in the surgical treatment of pancreatic diseases according to the literature.MATERIALS AND METHODS: Literature searched in Russian and English for the period from 2017 to 2022 in Medline/PubMed, RSCI/Elibrary, CyberLeninka, Google Scholar databases. The search was conducted on the keywords: pancreas, chronic pancreatitis, pancreatic cancer, pancreatic resection, computed tomography, 3-D modeling, 3-D reconstruction, surgical planning, surgical intervention, pancreas, chronic pancreatitis, pancreas cancer, pancreatectomy, computed tomography, 3-D modeling, 3D reconstruction, surgical planning.RESULTS: 49 publications on various aspects of the use of 3D modeling in pancreatic surgery were included in the final analysis. The diagnostic value of building three-dimensional models in assessing the resectability of pancreatic tumors, identifying individual topographic and anatomical features of the pancreatobiliary zone, which should be taken into account during surgery to avoid intra- and postoperative complications, is shown. Examples of a description based on 3D modeling of rare vascular anomalies and cysts that are not visualized according to standard computed tomography in patients who are scheduled for pancreatic surgery are presented. The importance of postoperative 3D modeling of the pancreas for assessing the adequacy of the surgical intervention and early detection of possible complications of the operation is indicated.CONCLUSION: 3D modeling is an innovative and promising diagnostic method that allows increasing the information content of standard computed tomography in pancreatic surgery. 3D models make it possible to select patients for pancreatic resection and substantiate the most optimal surgical strategy. In the future, we should expect an improvement in the results of surgical treatment of pancreatic tumors and complicated pancreatitis.ВВЕДЕНИЕ: Хирургические вмешательства на поджелудочной железе отличаются технической сложностью и сопровождаются достаточно большим количеством осложнений, что во многом обусловлено вариантой анатомией поджелудочной железы.ЦЕЛЬ: Оценить возможности 3D-моделирования при хирургическом лечении заболеваний поджелудочной железы по данным литературы.МАТЕРИАЛЫ И МЕТОДЫ: Выполнен поиск литературы на русском и английском языках за период с 2017 по 2022 гг. в базах данных Medline/PubMed, РИНЦ/Elibrary, КиберЛенинка, Google Scholar по ключевым словам: поджелудочная железа, хронический панкреатит, рак поджелудочной железы, резекция поджелудочной железы, компьютерная томография, 3D-моделирование, 3D-реконструкция, хирургическое планирование, хирургическое вмешательство, pancreas, chronic pancreatitis, pancreas cancer, pancreatectomy, computed tomography, 3D modeling, 3D reconstruction, surgical planning.РЕЗУЛЬТАТЫ: В окончательный анализ были включены 49 публикаций, посвященных различным аспектам применения 3D-моделирования в хирургии поджелудочной железы. Показана диагностическая ценность построения трехмерных моделей в оценке резектабельности опухолей поджелудочной железы, выявлении индивидуальных топографо-анатомических особенностей панкреатобилиарной зоны, которые должны учитываться во время операции во избежание интра- и послеоперационных осложнений. Представлены примеры описания на основе 3D-моделирования редких сосудистых аномалий и кист, не визуализированных по данным стандартной компьютерной томографии, у пациентов, которым планируется операция на поджелудочной железе. Обозначена значимость послеоперационного 3D-моделирования поджелудочной железы для оценки адекватности проведенного хирургического вмешательства и раннего выявления возможных осложнений операции.ЗАКЛЮЧЕНИЕ: 3D-моделирование является инновационным и перспективным методом диагностики, который позволяет повысить информативность стандартной компьютерной томографии в хирургии поджелудочной железы. 3D-модели позволяют отобрать пациентов для резекции поджелудочной железы и обосновать оптимальную хирургическую стратегию. В перспективе следует ожидать улучшение результатов хирургического лечения опухолей поджелудочной железы и осложненного панкреатит

Near field scanning optical microscopy for investigation of high power semiconductor lasers

В данной работе были исследованы карты распределения ближнего поля InGaAs/GaAs/AlGaAs полосковых инжекционных лазеров при различных токах накачки. Было показано, что в структурах, состоящих из двух резонансно связанных волноводов, наблюдается подавление мод высоких порядков.Near field intensity distributions of InGaAs/GaAs/AlGaAs lasers including broadened waveguides based on coupled large optical cavity (CLOC) structures were investigated. It was demonstrated that scanning near field optical microscopy gives direct proof of suppressing the transverse high-order mode lasing.Работа выполнена при поддержке РНФ (соглашение № 14-42-00006-П

Research of methods of control of the hidden emptiness by different ways

Представлені результати по дослідженню існуючих методів пошуку об’єктів у вкриваючих середовищах, проведений аналіз вкриваючих середовищ, що найбільш часто зустрічаються, і предметів заховання, проведений аналіз існуючого приладового забезпечення для вирішення цих завдань, а також сформульовані основні вимоги до сучасного приладу, який вирішує широкий круг завдань методом неруйнуючого контролю.Presented results on research of existent methods of search of objects in covering environments, conducted analysis of covering environments, that meets often, and the articles of that hides, conducted analysis of the existent device providing for the decision of these tasks, and also the formulated basic requirements to the modern device deciding wide circle of tasks by the method of nondestructive control