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The purpose of this paper is to investigate the heat and mass transport characteristics in microchannel reactors with non-uniform catalyst distributions.

A two-dimensional model is developed to study the heat and mass transport characteristics in microchannel reactors. The heat and mass transport processes in the microchannel reactors with non-uniform catalyst distribution in the catalytic combustion channel are also studied.

The simulated results are compared in terms of the distributions of species mole fraction, temperature and reaction rate for the conventional and new designed reactors. It is found that the chemical reaction, heat and mass transport processes are significantly affected and the maximum temperature in the reactor is also greatly reduced when a non-uniform catalyst distribution is applied in the combustion catalyst layer.

This study can improve the understanding of the transportation characteristics in microchannel reactors with non-uniform catalyst distributions and provide guidance for the design of microchannel reactors.

The design of microchannel reactors with non-uniform catalyst distributions can be used in methane steam reforming to reduce the maximum temperature inside the reactor.

An intelligent gas sensor has been developed using thick‐film techniques to create a semiconducting oxide surface with carefully varied catalytic properties. An integral heater causes the surface to react with combustible gases and the resulting resistance map of the surface forms a signature that can be related to the functional groups present in the gas. For example, alcohols, ketones and alkanes have distinct, recognisable signatures on one sensor model.

Because domestic heating appliances have the advantage of reducing emissions of greenhouse gas, their use is greatly increased and is largely recommended by European governments. However, some recent studies revealed that residential wood stoves and inserts are the source of many chemicals in the form of gases (CO₂, CO, SO₂, NO_x), volatile organic compounds (alkane, alkenes, benzene, etc. …) and tars (mainly constituting poly‐aromatic hydrocarbons). The most important of them in terms of the emission factor and impact on environment and human health are carbon monoxide and fine particles. The aim of this study is to test the activity of a Pd‐based catalyst on the reduction of gas and particles during wood combustion in a domestic fireplace.

A catalytic system, placed at the exit of the fireplace, was developed to reduce pollutants. Pollutant characterization of a domestic fireplace from FONDIS SA, according to two paces of functioning (nominal and low‐charge), was performed with and without the presence of the catalyst. Fine and ultrafine particle distributions were characterized using an Electrical Low Pressure Impactor.

The presence of a catalyst drastically decreases the emission factors of CO. Though performing efficiently with respect to the total suspended particles emission factor, it does not significantly affect the emission factors of aerosols. Nevertheless, in the presence of the catalyst, air supply conditions slightly modify size distributions of PM0.1 to PM10.

A purification assembly, having catalysts for gases and combustion fumes from solid fuel heating apparatus, was patented and fireplaces are now commercially available from FONDIS SA.

This work was an adaptation of the catalytic system present in the automotive Diesel exhaust engines. It was not necessary to consult previous laboratory experiments in order to perform its activity because it was directly tested at the duct fireplace.

The purpose of this paper is to introduce a robust mathematical model and finite element‐based numerical approach to solve solid oxide fuel cell (SOFC) problems.

A robust mathematical model is constructed by studying pros and cons of different SOFC and other fuel cell models. The finite element‐based numerical approach presented is a unified approach to solve multi‐disciplinary aspects arising from SOFC problems. The characteristic‐based split approach employed here is an efficient way of solving various flow, heat and mass transfer regimes in SOFCs.

The results presented show that both the model and numerical algorithm proposed are robust. Furthermore, the approaches proposed are general and can be easily extended to other similar problems of practical interest.

The model proposed is the first of this kind and the unified approach for solving flow, heat and mass transfer within a fuel cell is also novel.

The Institute for the Future (IFTF) has collaborated with the Rockefeller Foundation and its Searchlight function to create a framework for broad engagement in strategic thinking about ways to catalyze change in the lives of poor or vulnerable communities. This paper seeks to focus on this broad‐based approach.

Starting from the top‐down horizon scan of the foundation's Searchlight partners – a network of horizon scanning organizations – IFTF created a public database of signals of innovation and disruption in the domain of poverty and social change. This signals database was used to build a visual map of catalysts for change, creating a simple hierarchy of four catalyst types, each containing four action zones and a pivotal challenge. This map provided the language and framework for engaging a global community in a serious game to extend the vision of the Searchlight function and capture novel ideas for innovations that could improve the lives of those in marginalized communities.

With an estimated global reach of 160,000 views and 1,600 game players from 79 countries, the game produced more than 18,000 ideas about catalysts for change.

This framework of foresight (the signals database) to insight (the visual map of catalysts for change) to action (global strategic game) demonstrates a way to integrate top‐down expert foresight with bottom‐up strategic ideation on a global scale.

For zero‐defect wave soldering of double‐sided and multilayer printed circuit boards, the copper through‐hole‐plating must be impervious to gas generated in the laminate for the period of a few seconds while the solder is molten. The kinetics of the gas evolution during soldering have been related quantitatively to the integrity of the plated copper. This in turn is related to the quality of the electroless copper (evaluated using the backlighting test), the nature and distribution of the catalyst (evaluated using X‐ray photoelectron spectroscopy) and the methods and effectiveness of the hole‐wall preparation (evaluated using scanning electron microscopy). The relevance of laboratory measurements has been confirmed on a wide range of industrial production plating lines.

The purpose of this paper is to describe two‐ and three‐dimensional numerical modelling of solid oxide fuel cells (SOFCs) by employing an accurate and stable fully matrix inversion free finite element algorithm.

A general and detailed mathematical model has been developed for the description of the coupled complex phenomena occurring in fuel cells. A fully matrix inversion free algorithm, based on the artificial compressibility (AC) version of the characteristic‐based split (CBS) scheme and single domain approach have been successfully employed for the accurate and efficient simulation of high temperature SOFCs.

For the first time, a stable fully explicit algorithm has been applied to detailed multi‐dimensional simulation transport phenomena, coupled to chemical and electrochemical reactions, in fluid, porous and solid parts of a SOFC. The accuracy of the present results has been verified via comparison with experimental and numerical data available in the literature.

For the first time, thanks to a stabilization analysis conducted, the AC‐CBS algorithm has been successfully used to numerically solve the generalized model, applied in this paper to describe transport phenomena through free fluid channels and porous electrodes of SOFCs, without the need of further conditions at the fluid‐electrode interface.

This research examines recent changes in retail distribution and the implications of such changes on the logistical support to stores in Scotland. As increasing volumes of stock are channelled through warehouses controlled by retailers, stock is being centralised in large regional distribution centres (RDCs) serving wide geographical markets. Scotland is geographically marginal to the mainstream operations of most British retailers; the research therefore focused upon the current pattern of retail distribution facilities in Scotland and the future demand for sites by retailers and third party contractors acting on their behalf. Data were collected by personal interview and postal questionnaire from a total of 63 multiple retailers and 23 distribution companies. Most retail multiples supply their Scottish outlets from RDCs in England, either by a direct trunk haul or via intervening transhipment or demountable points. There has been a tendency for both manufacturers and retailers to withdraw stockholding from Scotland and serve the Scottish market from warehouses in England. Many of these companies, however, continue to require a break‐bulk operation north of the border. While the main phase of RDC development appears to be over, particularly in the grocery trade, it is likely that significant new investment in distribution facilities in Scotland will occur in the near future. Seventeen of the retailers in the survey expected to undertake some form of distribution development by 1995, eight of them anticipated setting up an RDC. In aggregate terms this translates into warehouse demand for around 80,000 square metres and approximately 20‐25 hectares of land. Although this and past investment has created thousands of jobs, job losses have also occurred through various displacement effects, most notably the rationalisation of retailers′ supply systems, the decimation of manufacturers′ depot networks and the closure of contractors′ common user depots.

This case study aims to explore the efforts of a small start-up company, whose unique solutions are being deployed in the fight against COVID-19, with encouraging results. Using innovative technology and local volunteer networks, they have set out to identify the medical needs of local care providers, while reducing the effects of fraud, corruption and mis-management.

This case study involved the interrogation of data made available by the company and an interview with the chief executive officer.

The research suggests that small enterprises can have a positive impact, far beyond what either the state or the market might assume. By properly equipping and empowering people at the grassroots level, they can identify and solve local resourcing issues and root-out fraud, corruption and mismanagement before they happen.

This is a unique approach to the problem of resource management in the non-profit sector, with implications for grant projects beyond the COVID-19 pandemic.

This study aims to investigate the morphology and physicochemical properties of BiOBr/Polyvinylidene fluoride (PVDF) composite membranes and the differences in the properties of BiOBr/PVDF composite membranes made by adding different precursor ratios during the casting process.

In this paper, sodium bromide and Bi(NO3)3 were used as precursors for the preparation of BiOBr photocatalysts, and PVDF membranes were modified by using the phase conversion method in conjunction with the in situ deposition method to produce BiOBr/PVDF hydrophilic composite membranes with both membrane separation and photocatalytic capabilities.

The characterization results confirmed that the composites were successfully and homogeneously co-mingled in the PVDF membranes. The related performance of the composite membrane was tested, and it was found that the composite membrane with the optimal precursor incorporation ratio had good photocatalytic efficiency and antipollution ability; the removal efficiencies of methyl orange, rhodamine B and methylene blue were 80.43%, 85.02% and 86.94%, respectively, in 2.5 h. The photocatalytic efficiency of composite membranes with different precursor ratios increased and then decreased with the increase of the precursor addition ratio.

The composite membrane is prepared by phase conversion method with in situ deposition method, and the BiOBr material has unique advantages for the degradation of organic dyes. The comprehensive experimental data can be known that the composite membrane prepared in this paper has high degradation efficiency and good durability for organic dyes.