Ash Melting Behavior of Rice Straw and Calcium Additives

Rice straw is potentially an appropriate feedstock material for biofuel production, since a huge amount of this postharvest residue is generated every year. The transformation of such agricultural biomass into densified products with a higher energy value and their subsequent combustion is associated with several questions. One of them is that rice straw exhibits a large formation of ash during combustion; thus, it is essential to know the nature of its ash melting behavior. Generally, during the combustion of straw biomass, ash sintering occurs in relatively low temperatures, resulting in the damaging of heating equipment. This negative aspect can be overcome by the addition of calcium-based additives. This paper aimed to study the ash melting behavior at a laboratory scale and to determine the ash melting points of rice straw mixed with calcium carbonate (CaCO3) and calcium hydroxide (Ca(OH)2) in different proportional ratios. The standardly produced ash samples from the rice straw obtained from Cambodia were constantly heated up in a muffle furnace, and characteristic temperatures of ash melting, i.e., shrinkage, deformation, hemisphere, and flow temperature, were recorded. The results showed that increasing the additive ratio did not bring linear growth of the melting temperatures. The addition of 1% CaCO3 showed an optimal positive impact of higher ash melting temperatures, and thus a better ability to abate the sintering of the rice straw ash.

A rare pancreatic neuroendocrine tumor with proinsulin-secreting activity

This paper presents a clinical case describing hypoglycemic condition with atypical symptoms in a young patient in the early postpartum period. Abdominal ultrasound revealed a large formation in the hook region of the pancreas, which was subsequently confirmed according to endoscopic ultrasound, CT and MRI. The idea of insulinoma was formed according to the presence of pancreatic formation, documented Whipple’s triad, and data on hyperinsulinism at the outpatient stage. However, the 72-hour fasting test showed no significant increase in insulin and C-peptide levels. After excluding other causes of hypoglycemia, the patient was suspected of having proinsulinoma, which was confirmed by increased blood proinsulin level. Gastropancreatoduodenal resection was performed. We detected a highly differentiated neuroendocrine pancreatic tumor with the expression of CD56, NSE, synaptophysin and chromogranin A, with a Ki-67 index of about 1%. After surgical treatment, hypoglycemic conditions were not observed.

A Complex Approach to Identity Construction among Children of the Indigenous Peoples of the North, Siberia, and the Far East of the Russian Federation

This article covers the process of identity construction in children; this process defines the focus of Russian educational policy, which also provides a venue for alternative ways to implement it. The article presents research on designing a system to form national, regional, and ethnocultural identity in children of the indigenous people of the North via the curriculum and teaching aids. The article examines regions of Russia inhabited by indigenous small-numbered peoples, as well as their distinctive features, which have a significant impact on the process of identity construction in children of the North. This has revealed the specific character of the large formation of positive types of identity within the educational system.

Madelung's disease – a case report

Introduction: Madelung’s disease is a rare illness manifested by the uncontrollable proliferation of unencapsulated adipose tissue which accumulates symmetrically in the hypodermis in the area of the neck, shoulders, back and thighs. As part of differential diagnosis it is necessary to investigate tumours in the area of the neck, dysfunction of the thyroid gland, Cushing’s syndrome and rare lipomatosis. Case report: In the case report, the authors present the case of a 52-year-old male patient with a large formation on the neck, trunk and the scrotal area. A suspicion of liposarcoma was expressed based on the imaging examinations performed. Results: Excisions of tumorous loci on several occasions were indicated for the patient. Lipomas without abnormalities were proven in all histological examinations. Conclusion: The diagnosis of Madelung’s disease is based on the clinical findings, imaging (computed tomography − CT, magnetic resonance imaging − MRI) and biopsy examination. Laboratory methods tend to focus rather on associated internal diseases. Treatment is only symptomatic and consists in surgical removal of the foci. However, it is often associated with the risk of recurrence.

5-ACETYL-8-HYDROXYQUINOLINE AND 5-FORMYL-8- HYDROXYQUINOLINE: CHELATING AGENTS FOR COMPLEXOMETRIC TITRATIONS

Metal–organic ligand complexes are essential to many technological developments from protein supramolecular assemblies to solvent extraction, complexometric titrations, and environmental remediation. We studied the chelating and acid-base properties in ethanol of two derivatives of 8-hydroxyquinoline (Q), 5-acetyl-8-hydroxyquinoline (A) and 5-formyl-8-hydroxyquinoline (F), of which applications as chelators are unknown. The ligands acidity followed the order F (pKa1 2.9; pKa2 9.5)> A (pKa1 4.8; pKa2 9.6)> Q (pKa1 5.3; pKa2 10.0) due to inductive effects of electronegative groups, formyl in F and acetyl in A. The higher acidity of F with respect to A was due to the higher electronegativity of the formyl group in F. This acidity order was reflected in larger formation constants of F-metal complexes with pKf values of 32 (Fe3+), 27.1 (Cu2+), 26.2 (Cu2+), and 24.9 (Pb2+), than with A, with pKf values of 31, 22.5, 21.4 and 21.2 with these metals, or the pKf values in the literature for Q. In summary, A and F resulted excellent chelators for metals in complexometric titrations with large formation constants; these large formation constants recommend the application of these compounds in masking, preconcentration, and titration of metals by complexation and oxidation-reduction reactions.

Effect of Cooling Rate on Intermetallic Compounds Formation in Sn-Ag-Cu-In Solder

The effect of the cooling rate in bonding on IMCs formation and their morphology in the solder joint with Sn-3.0Ag-0.7Cu-5.0In (mass%) lead-free solder was investigated. As the substrate, the Cu plate and the Cu plate with electroplated Ni were prepared. Bonding was conducted in the vacuum atmosphere, and bonding temperature and time were 300°C and 10 minutes, respectively. The cooling rates in the bonding were changed from 0.02°C/s to 0.2°C/s. In both Cu/Cu and Cu/Ni joints, scallop-shaped IMCs form at the joint interfaces regardless of the cooling rate. In the Cu/Cu joint, Cu6(Sn,In)5 and Cu3(Sn,In) layers form at the joint interface. In the Cu/Ni joint, (Cu,Ni)6(Sn,In)5 and (Cu,Ni)3(Sn,In) layers form at the joint interface with Cu and the (Cu,Ni)6(Sn,In)5 layer forms at the joint interface with Ni. Die shear force of the Cu/Ni joints are a little larger than those of the Cu/Cu joints. Fracture occurs in the boundary between the scallop-shaped layer or the granular IMC layer and the layered IMC in both joints. The cooling rate from the peak temperature to solidification is an important factor to decide the shape of formed IMC. When the cooling rate is high and supercooling becomes large, formation of pillar-shaped IMCs occurs easily.

Longer, faster and heavier freight trains

Purpose The purpose of this paper is to examine the necessity of longer and/heavier and/or faster freight train operations and their viability in the European context. Design/methodology/approach Using a case study, the current research applies qualitative methods, including desktop research and informal discussion with the rail freight industry and shippers. The case study is the recently conducted trial of 1.5 km long Marathon freight train in Europe. Findings The research finds that at this stage there is no commercial necessity of running a 1.5 km long train. There are technical and operational limitations which are less problematic, but the commercial necessity is a must and that will need sufficient traffic volume on a longer route (to justify extra time and cost incurred in marshalling yard and reasonable pre- and post-consolidated rail transport haul). The time required to form up/disperse such large formation could arguably be a major constraint for the train itself as well as for other services run on the same network. The authors agree in principle with the “do more with less” notion and the necessity of faster train concept. Also, the authors are agreeing with the heavier train aspect. Practical implications Considering the current and future (more semi-finished and finished, containerised) cargo trend, it is more important that freight train is operated consistently, reliably, and commercially attractive relatively faster and frequent serving moderate distances (around 300+ km). Towards this, the operation of merging two (or more) short trains to form up to 750 m long trains should be explored, in particular on the nine Rail Freight Corridors, to identify the potential and realistic opportunities for commercial deployment of “longer and/or faster and/or and heavier” freight train. Social implications At the moment there is no need of a 1.5 km long freight train to improve the performance of EU railways. Originality/value The case study provides an important platform for debate on the contemporary notion of “longer”, “faster” and “heavier” freight trains in the European context.

Density-Based Production-Data Analysis of Gas Wells With Significant Rock-Compressibility Effects

Summary The state-of-the-art analysis of the production performance of gas wells relies on material-balance concepts combined with pseudopressure and pseudotime for rate-time decline analysis and reserves estimations. In many cases, rock compressibility and reservoir pore-volume (PV) change are either neglected or accounted for by replacing gas compressibility with total compressibility values. In this work, we extend the applicability of a rescaled exponential and density-based decline-analysis approach (Ayala and Ye 2013a, b; Zhang and Ayala 2014a, b) for the decline analysis of gas systems experiencing significant rock-compressibility effects. We formally derive the density-based analytical techniques that rigorously capture formation-compressibility effects during the analysis of gas-well-production data during boundary-dominated flow, which proves crucially important for high-pressure and/or large-formation-compressibility gas-reservoir systems. The proposed formulation enables the calculation and correct prediction of well performance and original gas in place (OGIP) by incorporating formation compressibility and the change of reservoir PV effects, which may prove crucially important in high-pressure and/or relatively large-formation-compressibility gas reservoirs. We also present the associated straight-line analysis technique used for OGIP determination on the basis of the density approach applicable to constant-bottomhole-pressure production and variable-flow-rate/pressure-drop systems.