Status Update on Bioelectrochemical Systems: Prospects for Carbon Electrode Design and Scale-Up

Bioelectrochemical systems (BES) employ enzymes, subcellular structures or whole electroactive microorganisms as biocatalysts for energy conversion purposes, such as the electrosynthesis of value-added chemicals and power generation in biofuel cells. From a bioelectrode engineering viewpoint, customizable nanostructured carbonaceous matrices have recently received considerable scientific attention as promising electrode supports due to their unique properties attractive to bioelectronics devices. This review demonstrates the latest advances in the application of nano- and micro-structured carbon electrode assemblies in BES. Specifically, in view of the gradual increase in the commercial applicability of these systems, we aim to address the stability and scalability of different BES designs and to highlight their potential roles in a circular bioeconomy.

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Electrochemical communication between microbial cells and electrodes via osmium redox systems

Biochemical Society Transactions ◽

10.1042/bst20120120 ◽

2012 ◽

Vol 40 (6) ◽

pp. 1330-1335 ◽

Cited By ~ 32

Author(s):

Kamrul Hasan ◽

Sunil A. Patil ◽

Dónal Leech ◽

Cecilia Hägerhäll ◽

Lo Gorton

Keyword(s):

Electron Transfer ◽

Biofuel Cells ◽

Major Group ◽

Electrochemical Biosensors ◽

Bioelectrochemical Systems ◽

Bacterial Cells ◽

Redox Systems ◽

Microbial Cells ◽

Fundamental Part ◽

Micro Organisms

Electrochemical communication between micro-organisms and electrodes is the integral and fundamental part of BESs (bioelectrochemical systems). The immobilization of bacterial cells on the electrode and ensuring efficient electron transfer to the electrode via a mediator are decisive features of mediated electrochemical biosensors. Notably, mediator-based systems are essential to extract electrons from the non-exoelectrogens, a major group of microbes in Nature. The advantage of using polymeric mediators over diffusible mediators led to the design of osmium redox polymers. Their successful use in enzyme-based biosensors and BFCs (biofuel cells) paved the way for exploring their use in microbial BESs. The present mini-review focuses on osmium-bound redox systems used to date in microbial BESs and their role in shuttling electrons from viable microbial cells to electrodes.

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AN ADVANCED ADAPTIVE FINITE ELEMENT CODE APPLIED FOR COATING-SUBSTRATE SIMULATION

Journal of Multiscale Modelling ◽

10.1142/s1756973711000376 ◽

2011 ◽

Vol 03 (01n02) ◽

pp. 91-107 ◽

Cited By ~ 3

Author(s):

JÜRGEN LEOPOLD ◽

KATRIN HELLER ◽

ARNDT MEYER ◽

REINER WOHLGEMUTH

Keyword(s):

Finite Element ◽

Fe Simulation ◽

Scale Up ◽

Computational Time ◽

Adaptive Finite Element ◽

Workpiece Surface ◽

Coated Tools ◽

Geometrical Simulation ◽

The Stability ◽

And Storage

The stability of coating-substrate systems influences the chip formation and the surface integrity of the new generated workpiece surface, too. Using finite element (FE) simulation, deformations, strains and stresses in coated tools, caused by external and internal loads, can be computed on a microscopic scale. Since both, the whole macroscopic tool (in mm-scale) and the microscopic coating layers (in μm-scale up to nm-scale) must be included in the same geometrical simulation model, graded high-resolution FE meshes must be used. Nevertheless, the number of nodes in the 3D computational FE grid reaches some millions, leading to large computational time and storage requirements. For this reason, an advanced adaptive finite element (AAFEM) software has been developed and used for the simulation.

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Coal cluster as a structural factor in the development of Kuzbass

E3S Web of Conferences ◽

10.1051/e3sconf/202131504004 ◽

2021 ◽

Vol 315 ◽

pp. 04004

Author(s):

Yuri Fridman ◽

Galina Rechko ◽

Olesya Khokhrina

Keyword(s):

Value Added ◽

Economic Transformation ◽

Coal Industry ◽

Macroeconomic Conditions ◽

Employment Dynamics ◽

The Status ◽

Analysis Of Dynamics ◽

To Come ◽

The Stability ◽

Negative Factors

The article contains the results of the analysis of dynamics and structural transformations of employment and production of gross value added (GVA), carried out by the authors on the material of Kuzbass. The study was carried out using the shift-share analysis for 2007–2018. We can state that the employment dynamics, which was negative during this period, was determined primarily by regional factors. The dynamics of GVA was influenced by national (positive) and regional (negative) factors. The contribution of structural shifts to the growth of GVA over the past decade was negative and insignificant, and the decline in the number of employed occurred with a scarcely changed employment pattern. The coal cluster remains the core of the Kuzbass economy and retains the status of its most efficient sector – there are no obvious candidates for the role of a new leader. Meanwhile, the high dependence of the coal industry on external macroeconomic conditions, fluctuations in world markets, makes the strategic outlook of the entire region's economy vulnerable and unstable. Therefore, it is important to find and implement such model of the socio-economic transformation of Kuzbass, which will help protect and ensure the stability of the region for decades to come.

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Fruit Seeds as Sources of Bioactive Compounds: Sustainable Production of High Value-Added Ingredients from By-Products within Circular Economy

Molecules ◽

10.3390/molecules24213854 ◽

2019 ◽

Vol 24 (21) ◽

pp. 3854 ◽

Cited By ~ 14

Author(s):

Fidelis ◽

Moura ◽

Kabbas Junior ◽

Pap ◽

Mattila ◽

...

Keyword(s):

Chemical Composition ◽

Circular Economy ◽

Raw Materials ◽

Scale Up ◽

Sustainable Use ◽

Value Added ◽

Water Soluble ◽

Lipophilic Compounds

The circular economy is an umbrella concept that applies different mechanisms aiming to minimize waste generation, thus decoupling economic growth from natural resources. Each year, an estimated one-third of all food produced is wasted; this is equivalent to 1.3 billion tons of food, which is worth around US$1 trillion or even $2.6 trillion when social and economic costs are included. In the fruit and vegetable sector, 45% of the total produced amount is lost in the production (post-harvest, processing, and distribution) and consumption chains. Therefore, it is necessary to find new technological and environmentally friendly solutions to utilize fruit wastes as new raw materials to develop and scale up the production of high value-added products and ingredients. Considering that the production and consumption of fruits has increased in the last years and following the need to find the sustainable use of different fruit side streams, this work aimed to describe the chemical composition and bioactivity of different fruit seeds consumed worldwide. A comprehensive focus is given on the extraction techniques of water-soluble and lipophilic compounds and in vitro/in vivo functionalities, and the link between chemical composition and observed activity is holistically explained.

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Activation of Soluble Polysaccharides with 1-Cyano-4-Dimethylaminopyridine Tetrafluoroborate (CDAP) for Use in Protein–Polysaccharide Conjugate Vaccines and Immunological Reagents. III Optimization of CDAP Activation

Vaccines ◽

10.3390/vaccines8040777 ◽

2020 ◽

Vol 8 (4) ◽

pp. 777

Author(s):

Andrew Lees ◽

Jackson F. Barr ◽

Samson Gebretnsae

Keyword(s):

Reaction Time ◽

Low Temperature ◽

Scale Up ◽

Optimal Time ◽

Conjugate Vaccines ◽

Maximal Activation ◽

Optimum Reaction ◽

Rapid Reaction ◽

The Stability ◽

High Level

CDAP (1-cyano-4-dimethylaminopyridine tetrafluoroborate) is employed in the synthesis of conjugate vaccines as a cyanylating reagent. In the published method, which used pH 9 activation at 20 °C (Vaccine, 14:190, 1996), the rapid reaction made the process difficult to control. Here, we describe optimizing CDAP activation using dextran as a model polysaccharide. CDAP stability and reactivity were determined as a function of time, pH and temperature. While the rate of dextran activation was slower at lower pH and temperature, it was balanced by the increased stability of CDAP, which left more reagent available for reaction. Whereas maximal activation took less than 2.5 min at pH 9 and 20 °C, it took 10–15 min at 0 °C. At pH 7 and 0 °C, the optimal time increased to >3 h to achieve a high level of activation. Many buffers interfered with CDAP activation, but DMAP could be used to preadjust the pH of polysaccharide solutions so that the pH only needed to be maintained. We found that the stability of the activated dextran was relatively independent of pH over the range of pH 1–9, with the level of activation decreased by 40–60% over 2 h. The use of low temperature and a less basic pH, with an optimum reaction time, requires less CDAP, improving activation levels while making the process more reliable and easier to scale up.

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Functional, Physical and Sensory Properties of Pulse Ingredients Incorporated into Orange and Apple Juice Beverages

Journal of Food Research ◽

10.5539/jfr.v4n5p143 ◽

2015 ◽

Vol 4 (5) ◽

pp. 143 ◽

Cited By ~ 3

Author(s):

Fatemeh Zare ◽

Valérie Orsat ◽

Joyce I. Boye

Keyword(s):

Orange Juice ◽

Apple Juice ◽

Protein Solubility ◽

Value Added ◽

Absorption Capacity ◽

Sensory Properties ◽

Foaming Properties ◽

Lentil Flour ◽

Promising Area ◽

The Stability

The objective of this study was to explore the use of pulse ingredients in the development of orange juice and apple juice supplemented beverages. Commercially available pulse ingredients including pea protein (PP), chickpea flour (CPF), lentil flour (LF) and pea fibre (PF) were selected and characterized with respect to specific functional properties (water holding capacity, fat absorption capacity, protein solubility, emulsifying and foaming properties). Apple juice was supplemented with 1-4% pulse ingredients, whereas a supplementation level of 1-2% was used for orange juice. The physical and sensory properties of the supplemented beverages were measured after production and during 3 weeks of refrigerated storage. Sensory attributes for both orange and apple juice supplemented with 1% and 2% pulse ingredients were similar to their respective controls (with and without pectin added). In terms of turbidity, supplementation increased the turbidity of apple juice and orange juice beverages at all levels, in comparison with control and pectin-added control samples. Supplemented samples, showed less satisfactory results in terms of cloud stability and color especially for orange juice beverages in comparison with their respective controls. Overall, while there are some hurdles to be overcome, the results suggest that when used at the 1-2% levels, PP, PF, CPF and LF could serve as potential value-added ingredients for beverage supplementation based on their physical and sensory properties. Further studies are, however, required in this promising area to improve the stability of the final production especially during storage.

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The 2018 Long Rainy Season in Kenya: Hydrological Changes and Correlated Land Subsidence

Remote Sensing ◽

10.3390/rs12091390 ◽

2020 ◽

Vol 12 (9) ◽

pp. 1390 ◽

Cited By ~ 1

Author(s):

Ashraf Rateb ◽

ElSayed Hermas

Keyword(s):

Land Subsidence ◽

Rainy Season ◽

Active Faults ◽

Wet Season ◽

Rainfall Events ◽

Environmental Disasters ◽

Hydrological Changes ◽

The Stability ◽

Sbas Insar ◽

Scientific Attention

The wettest 2018 long rainy season (March to May (MAM)) resulted in daily intensive rainfall events in East Africa that have seriously affected the environment and economy in many countries. Land subsidence is one of the environmental disasters that has occurred due to the long rainy season in Kenya for many years. However, it has received limited scientific attention. In this paper, we incorporate hydrological (soil moisture active–passive (SMAP) and loading models) and geodetic data (global positioning system (GPS) and interferometric synthetic aperture radar (InSAR)) to study hydrological changes and their associated subsidence potential in Kenya. Results show that widespread subsidence of more than 20 mm was associated with the MAM season in Kenya during 2018, based on SBAS InSAR measurements. The high values of land subsidence were well correlated with the areas of intense flooding during the MAM season. The widespread subsidence during the wet season has implications for the stability of the earth’s surface during the season rather than creating the possibility of potential stresses along active faults. These stresses may trigger seismicity that is expected to pose risks to urban features. The results of the current study can help governmental authorities to adopt proper urban planning that avoids or minimizes the risks of land subsidence in the areas of sinkholes.

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Comparison of E-Textile Techniques and Materials for 3D Gesture Sensor with Boosted Electrode Design

Sensors ◽

10.3390/s20082369 ◽

2020 ◽

Vol 20 (8) ◽

pp. 2369 ◽

Cited By ~ 1

Author(s):

Josue Ferri ◽

Raúl Llinares Llopis ◽

Gabriel Martinez ◽

José Vicente Lidon Roger ◽

Eduardo Garcia-Breijo

Keyword(s):

Screen Printing ◽

Critical Parameters ◽

Electrode Design ◽

Conductive Ink ◽

Detection Rates ◽

Conductive Materials ◽

Specific Parameter ◽

Environmental Variations ◽

Manufacturing Techniques ◽

The Stability

There is an interest in new wearable solutions that can be directly worn on the curved human body or integrated into daily objects. Textiles offer properties that are suitable to be used as holders for electronics or sensors components. Many sensing technologies have been explored considering textiles substrates in combination with conductive materials in the last years. In this work, a novel solution of a gesture recognition touchless sensor is implemented with satisfactory results. Moreover, three manufacturing techniques have been considered as alternatives: screen-printing with conductive ink, embroidery with conductive thread and thermosealing with conductive fabric. The main critical parameters have been analyzed for each prototype including the sensitivity of the sensor, which is an important and specific parameter of this type of sensor. In addition, user validation has been performed, testing several gestures with different subjects. During the tests carried out, flick gestures obtained detection rates from 79% to 89% on average. Finally, in order to evaluate the stability and strength of the solutions, some tests have been performed to assess environmental variations and washability deteriorations. The obtained results are satisfactory regarding temperature and humidity variations. The washability tests revealed that, except for the screen-printing prototype, the sensors can be washed with minimum degradation.

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Physico-chemical Characteristics and Oxidative Stability of Date-Pits Oil during Storage at Different Temperatures

International Journal of Food Engineering ◽

10.1515/ijfe-2015-0173 ◽

2016 ◽

Vol 12 (4) ◽

pp. 385-393

Author(s):

Naima Al-Kharousi ◽

Mohammed Al-Khusaibi ◽

Ismail Al-Bulushi ◽

Nejib Guizani ◽

Mostafa Waly ◽

...

Keyword(s):

Oxidative Stability ◽

Value Added ◽

Stability Index ◽

Acid Value ◽

Food Ingredients ◽

C Storage ◽

Physico Chemical ◽

Different Temperatures ◽

The Stability ◽

Date Pits

Abstract In this study, oxidative stability of date-pits (i. e. Khalas variety) was investigated during storage as a function of temperature. The stability of date-pits oil was determined by measuring acid value (AV), peroxide value (PV), p-anisidine value (PAV), tocopherol and oxidative stability index. Initial characteristics of oil were assessed by measuring its physico-chemical and melting characteristics, fatty acids composition and aflatoxin. Storage of date-pits caused highest reduction in linoleic acid (C18:2, ω6) followed by oleic acid (C18:1, ω9). AV, PV and PAV of the fresh oil were 1.41 mg KOH/g oil, 3.30 meq/kg oil and 0.60, respectively. These values increased linearly at slower rate in the case of 30 °C storage, while sharp rise was observed after 40 days in cases of 100 and 150 °C storage (p < 0.05). The results of this study indicate that date pits oil had a good oxidative and thermal stability and could thus be used to develop value-added food ingredients.

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