Refinement of indicators characterizing fouling and slagging for coals with low slagging propensities as applied to the standard and zone-wise methods for thermal design of furnace chambers and to mathematical models

Methods for estimating indicators characterizing thermal resistance of waterwall tubes with deposits in the case of using coals with low slagging propensities (i.e., coals not prone to producing strong ferrous deposits) are presented.     

Ultrafast Hole‐Transfer Dynamics in Polymer/PCBM Bulk Heterojunctions

Ultrafast dynamics of the hole‐transfer process from methanofullerene to a polymer in a polymer/PCBM bulk heterojunction are directly resolved. Injection of holes into MDMO‐PPV is markedly delayed with respect to [60]PCBM excitation. The fastest component of the delayed response is attributed to the PCBM–polymer hole‐transfer process (30 ± 10 fs), while the slower component (～150 fs) is provisionally assigned to energy transfer and/or relaxation inside PCBM nanoclusters. The charge generation through the hole transfer is therefore as fast and efficient as through the electron‐transfer process. Exciton harvesting efficiency after PCBM excitation crucially depends on the concentration of the methanofullerene in the blend, which is related to changes in the blend morphology. Ultrafast charge generation is most efficient when the characteristic scale of phase separation in the blend does not exceed ～20 nm. At larger‐scale phase separation, the exciton harvesting dramatically declines. The obtained results on the time scales of the ultrafast charge generation after PCBM excitation and their dependence on blend composition and morphology are instrumental for the future design of fullerene‐derivative‐based photovoltaic devices.     

Formation of Structure in Clad Abrasion-Resistant Alloys of the Fe – Cr – C – Mo – Ni – Ti – B System Under the Effect of Ultrafine Particles of Titanium Nitride

Metal Science and Heat Treatment - The behavior of the structure of abrasion-resistant alloys of the Fe – Cr – C – Mo – Ni – Ti – B system during electric arc...     

Computational Analysis of Molnupiravir

In this work, we report in-depth computational studies of three plausible tautomeric forms, generated through the migration of two acidic protons of the N⁴-hydroxylcytosine fragment, of molnupiravir, which is emerging as an efficient drug to treat COVID-19. The DFT calculations were performed to verify the structure of these tautomers, as well as their electronic and optical properties. Molecular docking was applied to examine the influence of the structures of the keto-oxime, keto-hydroxylamine and hydroxyl-oxime tautomers on a series of the SARS-CoV-2 proteins. These tautomers exhibited the best affinity behavior (−9.90, −7.90, and −9.30 kcal/mol, respectively) towards RdRp-RTR and Nonstructural protein 3 (nsp3_range 207–379-MES).     

High‐Efficiency PbS Quantum‐Dot Solar Cells with Greatly Simplified Fabrication Processing via “Solvent‐Curing”

PbS quantum‐dot (QD) solar cells are promising candidates for low‐cost solution‐processed photovoltaics. However, the device fabrication usually requires ten more times film deposition and rinsing steps, which is not ideal for scalable manufacturing. Here, a greatly simplified deposition processing is demonstrated by replacing methanol with acetonitrile (ACN) as the rinsing solvent. It is discovered that ACN can effectively “cure” the film cracks generated from the volume loss during the solid‐state ligand‐exchange process, which enables the deposition of thick and dense films with much fewer deposition steps. Meanwhile, due to the aprotic nature of ACN, fewer trap states can be introduced during the rinsing process. As a result, with only three deposition steps for the active layer, a CPVT‐certified 11.21% power conversion efficiency is obtained, which is the highest efficiency ever reported for PbS QD solar cells employing a solid‐state ligand‐exchange process. More importantly, the simple film‐deposition processing provides an opportunity for the future application of QDs in low‐cost printing of optoelectronic devices.     

Crystal and electronic structure engineering of tin monoxide by external pressure

Although tin monoxide (SnO) is an interesting compound due to its p-type conductivity,a widespread application of SnO has been limited by its narrow band gap of...     

A semi-automated “blanket” method for renal segmentation from non-contrast T1-weighted MR images

Objective

To investigate the precision and accuracy of a new semi-automated method for kidney segmentation from single-breath-hold non-contrast MRI.

Materials and methods

The user draws approximate kidney contours on every tenth slice, focusing on separating adjacent organs from the kidney. The program then performs a sequence of fully automatic steps: contour filling, interpolation, non-uniformity correction, sampling of representative parenchyma signal, and 3D binary morphology. Three independent observers applied the method to images of 40 kidneys ranging in volume from 94.6 to 254.5 cm³. Manually constructed reference masks were used to assess accuracy.

Results

The volume errors for the three readers were: 4.4 % ± 3.0 %, 2.9 % ± 2.3 %, and 3.1 % ± 2.7 %. The relative discrepancy across readers was 2.5 % ± 2.1 %. The interactive processing time on average was 1.5 min per kidney.

Conclusions

Pending further validation, the semi-automated method could be applied for monitoring of renal status using non-contrast MRI.