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ZnO--TiO2 thin films containing 0.5 mol%, 1.0 mol%, and 5.0 mol% ZnO were synthesized by oxidative solidphase pyrolysis. The materials contained anatase and rutile phases with particle size of 6-13 nm, as confirmed using X-ray phase analysis and scanning electron microscopy. When a certain number of ZnO crystallites appeared in the TiO2 film structure in the temperature range of room temperature to 220 °C, a two-level response of the film resistance was observed, differing by approximately 10%, as obtained by electrophysical measurements. The two-level response correlates with the formation of two donor energy levels of 0.28 and 0.33 eV in the band structure of the ZnO--TiO2 films. The donor level with a higher activation energy corresponded to the Ti vacancy (V-Ti), and that with a lower activation energy corresponded to the Zn vacancy (V-Zn). Two levels of gas-sensitive properties were noted for 0.5ZnO--TiO2, 1ZnO--TiO2, and 5ZnO--TiO2 under the influence of 50 ppm NO2 at 250 °C. Such two-level responses can be ascribed to the pinning of the Fermi level on ZnO and TiO2 nanocrystallites. The mechanism of the beak-shaped and two-level responses of sensors based on composite nanomaterials when exposed to various gases was elucidated. [ABSTRACT FROM AUTHOR]

Thin nanocomposite films based on tin dioxide with a low content of zinc oxide (0.5–5 mol.%) were obtained by the sol–gel method. The synthesized films are 300–600 nm thick and contains pore sizes of 19–29 nm. The resulting ZnO–SnO2 films were comprehensively studied by atomic force and Kelvin probe force microscopy, X-ray diffraction, scanning electron microscopy, and high-resolution X-ray photoelectron spectroscopy spectra. The photoconductivity parameters on exposure to light with a wavelength of 470 nm were also studied. The study of the photosensitivity kinetics of ZnO–SnO2 films showed that the film with the Zn:Sn ratio equal to 0.5:99.5 has the minimum value of the charge carrier generation time constant. Measurements of the activation energy of the conductivity, potential barrier, and surface potential of ZnO–SnO2 films showed that these parameters have maxima at ZnO concentrations of 0.5 mol.% and 1 mol.%. Films with 1 mol.% ZnO exhibit high response values when exposed to 5–50 ppm of nitrogen dioxide at operating temperatures of 2 0 0 ∘ C and 2 5 0 ∘ C. [ABSTRACT FROM AUTHOR]

AbstractMicroreactor technologies are required to provide reliable carbon-free power generation in remote applications. The heat pipe–cooled microreactor concept, in particular, offers notable advantages due to the passive operation of heat pipes, enabling increased reliability and simplicity in a more compact form factor. There is a significant need for experimental work to aid and expedite the deployment of heat pipe microreactors due to their unique technological characteristics. Thus, there has been increased interest in heat pipe experiments by numerous institutions in order to support these efforts.The present work is a comprehensive review of recent heat pipe experiments from six major institutions, describing their designs, instruments, methods, and results. In addition, this paper also presents a background on heat pipe experiments along with discussions on instrumentation, accident scenarios, wick enhancement, and proposed future directions. [ABSTRACT FROM AUTHOR]

Background: According to the International Diabetes Federation (2021), high glucose levels during pregnancy affect approximately 16.7% of cases, with 80.3% of pregnant women developing gestational diabetes. In the Republic of Moldova, over the last 5 years, diabetes during pregnancy has been observed in around 2.20% of cases, with a 1.5 times increase in morbidity over the last decade. Managing diabetes during pregnancy and labor represents a pressing concern due to potential maternal and fetal complications. Objective: This study aims to investigate specific aspects of pregnancy and labor evolution in women with diabetes. Material and methods: A retrospective study was conducted on 243 patients at the Tertiary Perinatal Center. Patients were categorized into three groups based on diabetes type: type I diabetes mellitus (DM) in 73 (30.1%) pregnant women, type II DM in 38 (15.6%) cases, and gestational diabetes (GD) in 132 (54.3%) cases. Data on medical history, clinical and laboratory information, fetal well-being (evaluated through cardiotocography (CTG), ultrasound, Doppler velocimetry), pregnancy progression, and childbirth were assessed. Results : Patient ages ranged from 17 to 44 years, with a mean age of 30.01±6.05 years. Obesity was prevalent in patients with type II DM (84.2%) and GD (70.5%), while it affected 15.1% of those with type I DM. Complications during pregnancy included: decompensation of type I DM in the third trimester (74.0%), often with diabetic angiopathy and neurological changes (75.3%). Pregnancy-induced hyp ertension occurred more in GD (18.2%). Severe preeclampsia was predominant in decompensated type I DM (15.1%) and type II DM (15.8%), often requiring emergency C-section. Diabetic fetopathy (44.9%) was associated with fetal distress and placental complex changes (23.0%), with two perinatal deaths. Preterm births were frequent (51.9%), often due to fetal or maternal reasons. Vaginal delivery occurred in 29.2% with 7 cases of vacuum extraction. C-section was performed in 70.8% due to diabetes decompensation, severe preeclampsia, fetopathy, or scarred uterus. Labor complications included premature rupture of membranes (16.9%), dystocic labor (15.8%), and fetal hypoxia (6.8%). Conclusions: Diabetes during pregnancy poses significant medical and social challenges, potentially complicating the perinatal period. Proper management is crucial to prevent maternal and neonatal complications. This study sheds light on the diverse challenges and outcomes associated with diabetes in pregnancy, emphasizing the need for comprehensive care and monitoring. [ABSTRACT FROM AUTHOR]