Self-Supporting g-C3N4 Nanosheets/Ag Nanoparticles Embedded onto Polyester Fabric as “Dip-Catalyst” for Synergic 4-Nitrophenol Hydrogenation

Herein, we report the design of a cost-effective catalyst with excellent recyclability, simple recuperation and facile recovery, and the examination between the reaction cycles via the development of self-supporting g-C3N4 nanosheets/Ag NPs polyester fabric (PES) using a simple, facile and efficient approach. PES fabrics were coated via a sono-coating method with carbon nitride nanosheets (GCNN) along with an in situ setting of Ag nanoparticles on PES coated GCNN surface producing PES-GCNN/Ag0. The elaborated textile-based materials were fully characterized using FTIR, 13C NMR, XRD, TGA, SEM, EDX, etc. Catalytic performance of the designed “Dip-Catalyst” demonstrated that the as-prepared PES-GCCN/Ag0 has effectively catalyzed the hydrogenation of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of NaBH4. The 3 × 3 cm2 PES-GCNN/Ag0 showed the best catalytic activity, displaying an apparent rate constant (Kapp) equal to 0.43 min−1 and more than 10 reusability cycles, suggesting that the prepared catalyst-based PES fabric can be a strong nominee for sustainable chemical catalysis. Moreover, the coated fabrics exhibited appreciable antibacterial capacity against Staphylococcus epidermidis (S. epidermidis) and Escherichia coli (E. coli). The present study opens up new opportunities for the future design of a low cost and large-scale process of functional fabrics.

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Effects of Ag contents on the microstructure and SERS performance of self-grown Ag nanoparticles/Mo–Ag alloy films

Nanotechnology Reviews ◽

10.1515/ntrev-2020-0058 ◽

2020 ◽

Vol 9 (1) ◽

pp. 751-759 ◽

Cited By ~ 2

Author(s):

Xinxin Lian ◽

Yuanjiang Lv ◽

Haoliang Sun ◽

David Hui ◽

Guangxin Wang

Keyword(s):

Ag Nanoparticles ◽

Large Scale ◽

Low Cost ◽

Film Surface ◽

Time Domain Analysis ◽

Alloy Film ◽

Scale Production ◽

Alloy Films ◽

Surface Enhanced Raman ◽

Ag Film

AbstractAg nanoparticles/Mo–Ag alloy films with different Ag contents were prepared on polyimide by magnetron sputtering. The effects of Ag contents on the microstructure of self-grown Ag nanoparticles/Mo–Ag alloy films were investigated using XRD, FESEM, EDS and TEM. The Ag content plays an important role in the size and number of uniformly distributed Ag nanoparticles spontaneously formed on the Mo–Ag alloy film surface, and the morphology of the self-grown Ag nanoparticles has changed significantly. Additionally, it is worth noting that the Ag nanoparticles/Mo–Ag alloy films covered by a thin Ag film exhibits highly sensitive surface-enhanced Raman scattering (SERS) performance. The electric field distributions were calculated using finite-difference time-domain analysis to further prove that the SERS enhancement of the films is mainly determined by “hot spots” in the interparticle gap between Ag nanoparticles. The detection limit of the Ag film/Ag nanoparticles/Mo–Ag alloy film for Rhodamine 6G probe molecules was 5 × 10−14 mol/L. Therefore, the novel type of the Ag film/Ag nanoparticles/Mo–Ag alloy film can be used as an ideal SERS-active substrate for low-cost and large-scale production.

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Development of All-Plastic Microvalve Array for Multiplexed Immunoassay

Volume 10: Micro- and Nano-Systems Engineering and Packaging ◽

10.1115/imece2014-38154 ◽

2014 ◽

Author(s):

Shancy Augustine ◽

Pan Gu ◽

Xiangjun Zheng ◽

Toshikazu Nishida ◽

Z. Hugh Fan

Keyword(s):

Large Scale ◽

Low Cost ◽

Simultaneous Detection ◽

Cost Effective ◽

Negative Control ◽

Sensitive Material ◽

Detection Scheme ◽

Power Battery ◽

Multiple Analytes ◽

Multiplexed Immunoassay

There is a need for low-cost immunoassays that measure the presence and concentration of multiple harmful agents in one device. Currently, comparable immunoassays employ a one-analyte-per-test format that is time consuming and not cost effective for the requirement of detecting multiple analytes in a single sample. For instance, if a spectrum of harmful agents, including E. coli O157, cholera toxin, and Salmonella typhimurium, should be simultaneously monitored in foods and drinking water, then a one-analyte-per-test would be inefficient. This work demonstrates a platform capable of simultaneous detection of multiple analytes in a single, low-cost, microvalve array-enabled multiplexed immunoassay. This multiplexed immunoassay platform is demonstrated in a prototype COC (cyclic olefin copolymer) device with a 2×3 array in which 6 analytes can be detected simultaneously. In order to contain and regulate the flow of reagents in the multichannel device, an array of microfluidic valves actuated by a thermally expandable material and microfabricated resistors have been developed to direct the flow to the necessary assay sites. The microvalve-based immunoassay is shown to be reliable, easy to operate, and compatible with large-scale integration. The all-plastic microvalves use paraffin wax as the thermally sensitive material which drastically reduces power consumption by latching upon closing so that pulsed power is required only to close and latch the microvalve until it is necessary to re-open the valve. The multiplexed detection scheme has been demonstrated by using three proteins, C reactive protein (CRP) and transferrin, both of which are biomarkers associated with traumatic brain injury (TBI) as well as bovine serum albumin (BSA) as the negative control. Since there are no external bulky pneumatic accessories required to operate/latch the microvalves in the device, this compact, thermally actuated and latching microvalve-enabled multiplexed immunoassay has the potential to realize a portable, low power, battery operated microfluidic device for biological assays.

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Performance of rapid diagnostic tests for HCV infection in serum or plasma

Future Microbiology ◽

10.2217/fmb-2020-0295 ◽

2021 ◽

Author(s):

Stéphane Chevaliez ◽

Françoise Roudot-Thoraval ◽

Christophe Hézode ◽

Jean-Michel Pawlotsky ◽

Richard Njouom

Keyword(s):

Hepatitis C ◽

Diagnostic Tests ◽

Large Scale ◽

Low Cost ◽

Antibody Test ◽

Cost Effective ◽

Rapid Diagnostic Tests ◽

Treatment Programs ◽

Clinical Sensitivity ◽

Cost Treatment

Aim: HCV diagnosis will become the bottleneck in eliminating hepatitis C. Simple, accurate and cost-effective testing strategies are urgently needed to improve hepatitis C screening and diagnosis. Materials & methods: Performance of seven rapid diagnostic tests (RDT) have been assessed in a large series (n = 498) of serum or plasma specimens collected in France and in Cameroon. Results: Specificity varied from 96.1 to 100%. The clinical sensitivity, compared with immunoassays as the reference, was high for all seven RDT (97.2–100%). The Multisure HCV antibody assay and OraQuick HCV rapid antibody test reached sensitivity ≥99%. Conclusion: A number of RDT may be suitable for WHO prequalification and may be implemented in the framework of large-scale low-cost treatment programs to achieve the WHO viral hepatitis objectives by 2030.

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Effect of Protocatechuic Acid on Euglena gracilis Growth and Accumulation of Metabolites

Sustainability ◽

10.3390/su12219158 ◽

2020 ◽

Vol 12 (21) ◽

pp. 9158

Author(s):

Xiaomiao Tan ◽

Jiangyu Zhu ◽

Minato Wakisaka

Keyword(s):

Euglena Gracilis ◽

Large Scale ◽

Protocatechuic Acid ◽

Biomass Yield ◽

Growth Promotion ◽

Low Cost ◽

Cost Effective ◽

Control Group ◽

Biological Functions ◽

First Time

The development of efficient, environmentally friendly, low-cost approaches used to boost the growth of microalgae is urgently required to meet the increasing demands for food supplements, cosmetics, and biofuels. In this study, the growth promotion effects of protocatechuic acid (PCA) in the freshwater microalga Euglena gracilis were confirmed for the first time. PCA is a simple phenolic compound derived from natural plants and has a range of biological functions. The highest biomass yield, 3.1-fold higher than that of the control, used at 1.3 g·L−1, was obtained at 800 mg·L−1 of PCA. The yields of the metabolites chlorophyll a, carotenoids, and paramylon in the presence of PCA at 800 mg·L−1 were 3.1, 3.3, and 1.7 times higher than those of the control group, respectively. The highest paramylon yield was achieved at a lower dosage of PCA (100 mg·L−1), which is considered to be feasible for economic paramylon production. The growth and biosynthesis of metabolites stimulated by phytochemicals such as PCA could be an efficient and cost-effective strategy to enhance the productivity of microalgae in large-scale cultivations.

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One year later: Highlighting the challenges and opportunities in disseminating a breathing-retraining digital behaviour change intervention

Digital Health ◽

10.1177/2055207620936441 ◽

2020 ◽

Vol 6 ◽

pp. 205520762093644

Author(s):

Ben Ainsworth ◽

Anne Bruton ◽

Mike Thomas ◽

Lucy Yardley

Keyword(s):

Behaviour Change ◽

Large Scale ◽

Digital Health ◽

Low Cost ◽

Controlled Trial ◽

Cost Effective ◽

Challenges And Opportunities ◽

Breathing Retraining ◽

One Year ◽

Randomised Controlled

Digital behaviour change interventions can provide effective and cost-effective treatments for a range of health conditions. However, after rigorous evaluation, there still remain challenges to disseminating and implementing evidence-based interventions that can hinder their effectiveness ‘in the real world’. We conducted a large-scale randomised controlled trial of self-guided breathing retraining, which we then disseminated freely as a digital intervention. Here we share our experience of this process after one year, highlighting the opportunities that digital health interventions can offer alongside the challenges that must be addressed in order to harness their effectiveness. Whilst such treatments can support many individuals at extremely low cost, careful dissemination strategies should be proactively planned in order to ensure such opportunities are maximised and interventions remain up to date in a fast-moving digital landscape.

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Evaluation of an Easy-to-Install, Low-Cost Dendrometer Band for Citizen-Science Tree Research

Journal of Forestry ◽

10.1093/jofore/fvz026 ◽

2019 ◽

Vol 117 (4) ◽

pp. 317-322

Author(s):

Michael G Just ◽

Steven D Frank

Keyword(s):

Citizen Science ◽

Urban Areas ◽

Large Scale ◽

Low Cost ◽

Acer Rubrum ◽

Cost Effective ◽

Stem Growth ◽

Growth Monitoring ◽

Eastern United States ◽

Highly Correlated

AbstractTree-stem growth is an important metric for evaluating many ecological and silvicultural research questions. However, answering these questions may require monitoring growth on many individual trees that span changing environments and geographies, which can incur significant costs. Recently, citizen science has been successfully employed as a cost-effective approach to collect data for large-scale projects that also increases scientific awareness. Still, citizen-science-led tree-growth monitoring requires the use of tools that are affordable, understandable, and accurate. Here, we compare an inexpensive, easy-to-install dendrometer band to two other bands that are more expensive with more complex installations. We installed a series of three dendrometers on 31 red maples (Acer rubrum) in two urban areas in the eastern United States. We found that the stem-growth measurements reported by these dendrometers were highly correlated and, thus, validate the utility of the inexpensive band.

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Towards High Performance Chemical Vapour Deposition V2O5 Cathodes for Batteries Employing Aqueous Media

Molecules ◽

10.3390/molecules25235558 ◽

2020 ◽

Vol 25 (23) ◽

pp. 5558

Author(s):

Dimitra Vernardou ◽

Charalampos Drosos ◽

Andreas Kafizas ◽

Martyn E. Pemble ◽

Emmanouel Koudoumas

Keyword(s):

Energy Storage ◽

High Performance ◽

Large Scale ◽

Electrode Materials ◽

Low Cost ◽

Aqueous Media ◽

Chemical Vapour ◽

Cost Effective ◽

Scale Production ◽

Environmentally Safe

The need for clean and efficient energy storage has become the center of attention due to the eminent global energy crisis and growing ecological concerns. A key component in this effort is the ultra-high performance battery, which will play a major role in the energy industry. To meet the demands in portable electronic devices, electric vehicles, and large-scale energy storage systems, it is necessary to prepare advanced batteries with high safety, fast charge ratios, and discharge capabilities at a low cost. Cathode materials play a significant role in determining the performance of batteries. Among the possible electrode materials is vanadium pentoxide, which will be discussed in this review, due to its low cost and high theoretical capacity. Additionally, aqueous electrolytes, which are environmentally safe, provide an alternative approach compared to organic media for safe, cost-effective, and scalable energy storage. In this review, we will reveal the industrial potential of competitive methods to grow cathodes with excellent stability and enhanced electrochemical performance in aqueous media and lay the foundation for the large-scale production of electrode materials.

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Before-and-After Empirical Bayes Evaluation of Citywide Installation of Driver Feedback Signs

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198120912243 ◽

2020 ◽

Vol 2674 (4) ◽

pp. 419-427

Author(s):

Mingjian Wu ◽

Karim El-Basyouny ◽

Tae J. Kwon

Keyword(s):

Traffic Safety ◽

Spatial Data ◽

Empirical Bayes ◽

Large Scale ◽

Low Cost ◽

Cost Effective ◽

Before And After ◽

Feedback Sign ◽

Driver Feedback ◽

Road Segments

Speeding is a leading factor that contributes to approximately one-third of all fatal collisions. Over the past decades, various passive/active countermeasures have been adopted to improve drivers’ compliance to posted speed limits to improve traffic safety. The driver feedback sign (DFS) is considered a low-cost innovative intervention that is being widely used, in growing numbers, in urban cities to provide positive guidance for motorists. Despite their documented effectiveness in reducing speeds, limited literature exists on their impact on reducing collisions. This study addresses this gap by designing a before-and-after study using the empirical Bayes method for a large sample of urban road segments. Safety performance functions and yearly calibration factors are developed to quantify the sole effectiveness of DFS using large-scale spatial data and a set of reference road segments within the city of Edmonton, Alberta, Canada. Likewise, the study followed a detailed economic analysis based on three collision-costing criteria to investigate if DFS was indeed a cost-effective intervention. The results showed significant collision reductions that ranged from 32.5% to 44.9%, with the highest reductions observed for severe speed-related collisions. The results further attested that the benefit–cost ratios, combining severe and property-damage-only collisions, ranged from 8.2 to 20.2 indicating that DFS can be an extremely economical countermeasure. The findings from this study can provide transportation agencies in need of implementing cost-efficient countermeasures with a tool they need to design a long-term strategic deployment plan to ensure the safety of traveling public.

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The Production of Reduced Graphene Oxide by a Low-Cost Vacuum System for Supercapacitor Applications

Materials Science Forum ◽

10.4028/www.scientific.net/msf.930.609 ◽

2018 ◽

Vol 930 ◽

pp. 609-612

Author(s):

Quezia Cardoso ◽

Franks Martins Silva ◽

Ligia Silverio Vieira ◽

Julio Cesar Serafim Casini ◽

Solange Kazume Sakata ◽

...

Keyword(s):

Graphene Oxide ◽

Large Scale ◽

Low Cost ◽

High Vacuum ◽

Cost Effective ◽

Practical Method ◽

Raw Material ◽

Vacuum System ◽

X Ray ◽

Pump Pressure

Graphene has attracted significant interest because of its excellent electrical properties. However, a practical method for producing graphene on a large scale is yet to be developed. Graphene oxide (GO) can be partially reduced to graphene-like sheets by removing the oxygen-containing groups and recovering the conjugated structure. GO can be produced using inexpensive graphite as the raw material via cost-effective chemical methods. High vacuum and temperature (10−7 mbar and 1100°C, respectively) conditions are well-known to enable the preparation of reduced powder at the laboratory scale. However, a large-scale high vacuum reduction system that can be routinely operated at 10−7 mbar requires considerable initial capital as well as substantial operational and maintenance costs. The current study aims at developing an inexpensive method for the large-scale reduction of graphene oxide. A stainless steel vessel was evacuated to backing-pump pressure (10−2 mbar) and used to process GO at a range of temperatures. The reduction of GO powder at low vacuum pressures was attempted and investigated by X-ray diffraction and Fourier transform infrared spectroscopy. The experimental results of processing GO powder at various temperatures (200–1000°C) at relatively low pressures are reported. The microstructures of the processed materials were investigated using scanning electron microscopy and chemical microanalyses via energy dispersive X-ray analysis.

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Theory and Manufacturing Processes of Solar Nanoantenna Electromagnetic Collectors

Journal of Solar Energy Engineering ◽

10.1115/1.4000577 ◽

2010 ◽

Vol 132 (1) ◽

Cited By ~ 68

Author(s):

D. K. Kotter ◽

S. D. Novack ◽

W. D. Slafer ◽

P. J. Pinhero

Keyword(s):

Large Scale ◽

Low Cost ◽

Cost Effective ◽

Optical Antenna ◽

Technological Barriers ◽

Large Scale Manufacture ◽

Future Work ◽

Optical Behavior ◽

Effective Proof ◽

Selection Of

The research described in this paper explores a new and efficient approach for producing electricity from the abundant energy of the sun, using nanoantenna (nantenna) electromagnetic collectors (NECs). NEC devices target midinfrared wavelengths, where conventional photovoltaic (PV) solar cells are inefficient and where there is an abundance of solar energy. The initial concept of designing NECs was based on scaling of radio frequency antenna theory to the infrared and visible regions. This approach initially proved unsuccessful because the optical behavior of materials in the terahertz (THz) region was overlooked and, in addition, economical nanofabrication methods were not previously available to produce the optical antenna elements. This paper demonstrates progress in addressing significant technological barriers including: (1) development of frequency-dependent modeling of double-feedpoint square spiral nantenna elements, (2) selection of materials with proper THz properties, and (3) development of novel manufacturing methods that could potentially enable economical large-scale manufacturing. We have shown that nantennas can collect infrared energy and induce THz currents and we have also developed cost-effective proof-of-concept fabrication techniques for the large-scale manufacture of simple square-loop nantenna arrays. Future work is planned to embed rectifiers into the double-feedpoint antenna structures. This work represents an important first step toward the ultimate realization of a low-cost device that will collect as well as convert this radiation into electricity. This could lead to a broadband, high conversion efficiency low-cost solution to complement conventional PV devices.

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