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An approach is presented for comprehensive and reliable analysis of the surface photovoltage (SPV) amplitude and phase spectral behaviour in various semiconductor materials and structures. In this approach the SPV signal is represented as a radial vector with magnitude equal to the SPV amplitude and angle with respect to the x-axis equal to the SPV phase. This model is especially helpful in complicated nanostructures, where more than one SPV formation processes arises during the spectrum run. The value of the proposed model has been demonstrated by the successful explanation of seemingly contradictory SPV amplitude and phase spectra of AlAs/GaAs superlattices with embedded GaAs quantum wells, grown on different GaAs substrates. This has provided useful information about the investigated nanostructures. The need for simultaneous examination of both SPV amplitude and SPV phase spectra in order to obtain a correct understanding of the experimental data is emphasized.

Twenty-two crude oils around the world, from which 19 are processed in the LUKOIL Neftohim Burgas (LNB) refinery, were characterized in the LNB research laboratory by measuring 67 properties. These 22 crude oils included light low sulfur, light sulfur, intermediate low sulfur, intermediate sulfur, intermediate high sulfur, heavy high sulfur, and extra heavy extra high sulfur crudes. A new mathematical approachthe intercriteria analysiswas employed to study the relations between the petroleum properties. It was found that the petroleum properties, density, and sulfur content, along with the crude oil simulated distillation, seem to be capable of providing the same information as that from the full assay of a crude oil. Crude oils containing insoluble asphaltenes (self-incompatible oils) were found to have a high content of low aromaticity naphtha and kerosene. It was found that the asphaltene solubility correlated with the asphaltene hydrogen content. The oil solubility power was found to correlate with the oil saturate content. The oil colloidal stability seems to be controlled by the following rule: "like dissolves like". The higher the aromaticity of the asphaltenes, the higher the aromaticity of the oil is required to keep the asphaltenes in solution. The processing of blends of oils which are incompatible or nearly incompatible may deteriorate the performance of the dewatering and desalting in the refinery, which consequently may damage the equipment due to accelerated corrosion, entailed by salt deposition. The processing of blends of oils, which are incompatible, not always can be related to an increased fouling.

Introduction The aim of this study is to demonstrate the real-life effectiveness and safety of insulin glargine 300 U/mL (Gla-300) in patients with type 2 diabetes (T2D) previously uncontrolled on NPH ± prandial insulin or premixed insulins in routine clinical practice in Bulgaria. Methods This was a 24-week prospective, observational study performed in 40 inpatient and outpatient sites across the country. Results A total of 286 patients were included in the study. The mean age (± SD) was 61.2 ± 10.0 years with duration of diabetes of 11.64 ± 7.5 years and body mass index (BMI) of 32.1 ± 5.7 kg/m 2 . HbA1c before Gla-300 initiation was 9.8 ± 1.0%, and fasting plasma glucose (FPG) was 13.1 ± 3.4 mmol/L. HbA1c and FPG change from baseline to week 24 was − 1.86% ( p < 0.001) and − 4.8 mmol/L ( p < 0.001), respectively. The proportion of patients reaching their individualized HbA1c at week 24 was 39.1% (95% CI 33.3–45.1%), while the proportion of patients reaching their individualized HbA1c target without confirmed and/or severe hypoglycaemia was 34.8% (95% CI 29.2–40.7%). At study end, 19.0% (95% CI 14.6–24.1%) achieved HbA1c < 7%. Body weight decreased from 88.3 to 87.0 kg from baseline to week 24 with mean change of − 1.3 kg ( p < 0.001). The incidence and event rates of anytime confirmed (≤ 3.9 mmol/L) and/or severe hypoglycaemia were low: 7.7% and 0.42 events per patient-year, respectively. The overall Insulin Treatment Satisfaction Questionnaire (ITSQ) score increased from 53.2 to 78.2 from baseline to week 24 and the difference of 25.1 ± 21.5 points was significant ( p < 0.001). Conclusions In real-life settings, Gla-300 significantly improved glycaemic control and insulin treatment satisfaction in people with T2D who were inadequately controlled with NPH ± prandial insulin or premixed insulin analogues. Improvement of glycaemic control was associated with a very low risk of hypoglycaemia and with significant weight loss irrespective of the previous insulin regimen. Supplementary Information The online version contains supplementary material available at 10.1007/s13300-021-01022-0.

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In relation to the constant requirement for reduction of sulfur level and low demand for fuel oil, this study presents an approach for utilization of unconverted vacuum tower bottom (UVTB) from the ebullated bed hydrocracking process, H-Oil technology, in bitumen production. The kinetic study shows a slower softening point increase for crude blend 70% Urals and 30% Middle Eastern than other feeds in the air-blowing process. Also, penetration values for straight run vacuum residue feeds decrease quicker than the increase in their softening point values. UVTB softening point increase at high temperature is faster and penetration decrease is slower than LNB SRVR. Air blowing is shown to improve the penetration index of UVTB to a greater extent than the SRVR one. The bottleneck of this new application of UVTB is its low resistance to hardening, determined by using a rolling thin film oven (RTFO), which limits its quantity up to 20−30% in blends.

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Thin films of SiO x (x = 1.15, d = 1 and 2 µm), deposited by thermal vacuum evaporation of SiO on n-and p-type crystalline Si or quartz substrates, and then furnace annealed at 250, 700 and 1000 • C, are studied. Optical and infrared transmission measurements prove phase separation upon annealing at 700 and 1000 • C and growth of amorphous Si nanoparticles upon annealing at 700 • C, whose optical band gap is ∼2.6 eV. High-resolution electron microscopy data confirm growth of Si nanocrystals with average size ∼5 nm in the films annealed at 1000 • C. Both kinds of transmission data were used to estimate the nanoparticle volume fraction and values of 0.2-0.25 and 0.25-0.30 for the films annealed at 700 and 1000 • C, respectively, are determined. Current-voltage characteristics (at fields >5 × 10 4 V cm −1 ) are measured on metal/SiO x /c-Si/metal structures to explore carrier transport mechanisms in all kinds of samples. They are nearly symmetric, which indicates that in all samples carrier transport via structures is dominated by the transport in the SiO x layers. It is concluded that current transport is space-charge-limited for the layers annealed at 250 • C. In the films further annealed at 700 • C containing amorphous nanoparticles, Poole-Frenkel transport mechanism is reported while tunnelling is assumed for the films annealed at 1000 • C.