Localized corrosion of (lean) duplex stainless steels in immersion units of urban wastewater treatment plants

With lower alloying cost and higher mechanical properties, lean duplex stainless steels can be an alternative to the more commonly used austenitic stainless steels. However, these alloys are still not the preferred choice, probably due to a lack of field experience. A study was thus initiated in view of defining the limits of use of selected (lean) duplexes for urban wastewater treatment units. The present paper shows the localized corrosion performance of selected lean duplexes in chloride contaminated solutions. The results are compared with austenitic S30403 and S31603 and with the more standard duplexes S82441 and S32205. The effect of welding was also investigated. Exposures in field municipal wastewater plants were conducted for 1 year in low and high chloride content units. The results show that lean duplexes S32101 and S32202 can be used as alternatives to S30403 and S31603 in low chloride electrolytes. At 500 ppm of chloride content, duplex stainless steel S32304 showed better corrosion resistance than S30403 and S31603. For higher chloride contents (1000 ppm and above) the standard duplexes S82441 and S32205 shall be preferred.     

Butyrate and Propionate Restore the Cytokine and House Dust Mite Compromised Barrier Function of Human Bronchial Airway Epithelial Cells

Barrier dysfunction of airway epithelium contributes to the development of allergies, airway hyper-responsiveness and immunological respiratory diseases. Short-chain fatty acids (SCFA) enhance and restore the barrier function of the intestinal epithelium. This study investigated whether acetate, propionate and butyrate enhance the integrity of bronchial epithelial cells. Differentiating human bronchial epithelial cells (16HBE) grown on transwells were exposed to butyrate, propionate and acetate while trans-epithelial electrical resistance was monitored over time. Restorative effects of SCFA were investigated by subsequent incubation of cells with IL-4, IL-13 or house dust mite extract and SCFA. SCFA effects on IL-4-induced cytokine production and the expression of zonula occludens-1 (ZO-1) and Mitogen-activated protein kinases (MAPK) signalling pathways were investigated by ELISA and Western blot assays. Propionate and butyrate enhanced the barrier function of differentiating 16HBE cells and induced complete recovery of the barrier function after exposure to the above-mentioned stimuli. Butyrate decreased IL-4-induced IL-6 production. IL-4 decreased ZO-1 protein expression and induced phosphorylation of extracellular signal-regulated protein kinases 1/2 (ERK1/2) and c-Jun N-terminal kinases (JNK) in 16HBE cells, both of which could be restored by SCFA. SCFA showed prophylactic and restorative effects on airway epithelial barrier function, which might be induced by increased ZO-1 expression.     

Two placebo-controlled crossover studies in healthy subjects to evaluate gastric acid neutralization by an alginate–antacid formulation (Gaviscon Double Action)

Objective: To investigate the intragastric acid neutralization activity of a combined alginate-antacid formulation.

Significance: Published studies have investigated the reflux-suppressing alginate component of Gaviscon Double Action (Gaviscon DA; RB, UK) but intragastric acid neutralization activity of the antacid component has not been evaluated in vivo.

Methods: Intragastric pH monitoring, using a custom-made 10-electrode catheter, was evaluated in a two-part exploratory study in healthy subjects; Part I (n?=?6) tested suitability of the catheter using antacid tablets (Rennie; Bayer, Germany); Part II (n?=?12) evaluated gastric acid neutralization activity of Gaviscon DA liquid (20?ml) versus placebo in fasted subjects using a randomized, open-label, crossover design. The primary endpoint was the percentage of time that intragastric pH ≥4 was measured during 30?min post-treatment. A confirmatory study of identical design was subsequently conducted (n?=?20).

Results: Monitoring pH using the multielectrode catheter was a viable approach, directly detecting changes in intragastric pH following a single dose of antacid tablets. In the exploratory study, the percentage of time that pH ≥4 during 30?minutes post-treatment was 46.8% with Gaviscon DA liquid versus 4.7% with placebo (p?=?0.0004). These findings were supported by the confirmatory study, where pH ≥4 was recorded 50.8% of the time with Gaviscon DA versus 3.5% with placebo (p?=?0.0051). In this study, Gaviscon DA was safe and well tolerated.

Conclusions: These studies demonstrate the effective acid neutralizing capacity of Gaviscon DA versus placebo in healthy, fasted subjects. This adds to the evidence base for the combination of alginates and antacids.     

Effectiveness of strategic environmental assessment in Poland

The paper presents the results of an evaluation of the effectiveness of SEA obtained as a result of a survey with the participation of stakeholders. In Poland, several hundred SEAs are conducted annually at the local and regional levels and several at the national level. Although the survey demonstrated that SEA is evaluated as effective or quite effective, the respondents pointed to several irregularities in the non-procedural dimension of effectiveness. The main ones in terms of substantive effectiveness are that SEA is rarely used to help develop plans/programmes and procedures are highly politicised. Moreover, low effectiveness in terms of variant assessment and cumulative impacts and nearly non-existent monitoring of the actual effects of implementing plans/programmes influence substantive effectiveness significantly. The respondents pointed to the problem resulting from the fact that plan-makers are unwilling to take into account the SEA recommended changes. They also emphasised that there are certain attempts to put pressure on SEA consultants to make the conclusions less stringent. Respondents indicate that in Poland the costs associated with conducting SEA often outweigh the profits. The research shows that the society is properly informed about SEA, but public involvement is still low.     

Taxonomy of digital community currency platforms*

ABSTRACT

Community currencies are used to pay for products or services within specific groups defined by geographical boundaries or specific common interests. Financial crises, social emergence in developing countries, and increased access to digital devices have stimulated a growing number of communities worldwide to develop digital currency projects. These projects use technologies ranging from traditional plastic cards to mobile phones and blockchain technologies. Following the design science research approach, this paper analyzes digital community currencies (DCCs) by developing a taxonomy based on platform architecture, governance, transactionality and virtuality. By investigating 22 DCC platforms around the world, 4 groups were distinguished: local, proprietary, commons and cyber. The identification of these four different groups of digital community currencies allows us to better discuss the potentials and limitations of each one of them. The presented taxonomy can be useful to researchers and practitioners both to explain and to design DCC platforms. Discussing each of the emerging categories from the proposed taxonomy helps us to provide insights into DCCs, offering a new theoretical frame for investigating the particular case of digital payment platforms.     

A fuzzy logic approach to reliable real-time recognition of facial emotions

Multimedia Tools and Applications - This paper represents our newly developed software for emotion recognition from facial expressions. Besides allowing emotion recognition from image files and...     

The influence of cap rock composition on hydrocarbon seep type in the Zagros oil fields,a study using Advanced Spaceborne Thermal Emission and Reflection Radiometer mineral map

The persistent natural hydrocarbon seepage in onshore basins challenges observation and exploration technologies, which are required to document and assess these valuable indications of the presence of oil and gas in the subsurface. This paper aims at demonstrating the relationship between the compositional variation of an evaporite cap rock and the types of seeps occurring at the surface. For this purpose, the multispectral Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data was utilized for mapping mineral variations of a petroleum system in the Zagros oil fields. Relative absorption-band depth (RBD), band rationing and the boosted regression trees (BRT) were applied to enhance and classify the mineral composition of evaporite, sandstone, and marly limestone formations. The gas seeps were associated with the areas of gypsum-bearing evaporite cap rock while oil seeps were mostly associated with calcite and clay zones within the cap rock, which was more prone to fracturing during the tectonic activities of the basin. It is suggested that the application of remote sensing in the oil and gas industry could be widened by detection of sleep-induced alteration to assess the efficiency of cap rock and to evaluate the productivity of reservoirs at a regional scale.     

Corrosion Behaviour of Type 316L Stainless Steel in Hot Caustic Aqueous Environments

Metals and Materials International - The corrosion behaviour of type 316L stainless steel in aqueous 30–50 wt%. NaOH at temperatures up to 90 °C has been elucidated....     

Developing conductive immiscible polystyrene/polypropylene blends with a percolated conducting polyaniline/polyamide filler by tuning its specific interactions with the styrene-based triblock compatibilizer grafted with maleic anhydride

An approach to induce conductivity in immiscible polystyrene/polypropylene (PS/PP) blends is described using a percolated conducting polyaniline/polyamide (PANI/PA) filler combined with a polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene-graft-maleic anhydride compatibilizer. The approach is based on the ability of the compatibilizer to concomitantly stabilize the cocontinuous morphology and to improve the state of dispersion of the PANI/PA filler. Selective localization of PANI/PA in the PS phase with improved filler dispersion is achieved with the optimal master batch (MB) preparation technique followed by its optimized sequence addition to the blend components. This results in an increase in the dc conductivity by six decades as compared with that of the neat compatibilized blend at an effective 4.8-wt % PANI concentration. An investigation of the effect of functionality and concentration of the filler and the compatibilizer on the filler connectivity in the blend is performed. The prevailing specific interactions are analyzed by Fourier transform infrared spectroscopy and thermogravimetric analysis of the MBs. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48433.     

Lab-Scale Microreactor Plant for the Study of Methylations with Liquid Chloromethane

Chloromethane is an important reagent for methylations in the process industry. However, as a gas suspected of causing cancer, it is rarely used at laboratory scale. Therefore, a setup is presented here for studies in a laboratory under safe and reproducible conditions. The use of a microreactor guarantees high heat transfer rates and a low holdup of the reagent. As a proof-of-concept, the reaction of chloromethane with the secondary amine morpholine in aqueous solution is investigated. By applying elevated pressures, a liquid-liquid system with enhanced solubility of chloromethane in the aqueous phase is accessible.