Recent Overview of Solar Photocatalysis and Solar Photo-Fenton Processes for Wastewater Treatment

This literature research, although not exhaustive, gives perspective to solar-driven photocatalysis, such as solar photo-Fenton and TiO2 solar photocatalysis, reported in the literature for the degradation of aqueous organic pollutants. Parameters that influence the degradation and mineralization of organics like catalyst preparation, type and load of catalyst, catalyst phase, pH, applied potential, and type of organic pollutant are addressed. Such parameters may also affect the photoactivity of the catalysts used in the studied solar processes. Solar irradiation is a renewable, abundant, and pollution-free energy source for low-cost commercial applications. Therefore, these solar processes represent an environmentally friendly alternative mainly because the use of electricity can be decreased/avoided.

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Automation of absolute protein-ligand binding free energy calculations for docking refinement and compound evaluation

Scientific Reports ◽

10.1038/s41598-020-80769-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Germano Heinzelmann ◽

Michael K. Gilson

Keyword(s):

Free Energy ◽

Early Stage ◽

Binding Free Energy ◽

Low Cost ◽

Free Energy Calculations ◽

Free Energies ◽

Energy Calculations ◽

Drug Candidates ◽

Binding Free Energy Calculations ◽

Binding Free Energies

AbstractAbsolute binding free energy calculations with explicit solvent molecular simulations can provide estimates of protein-ligand affinities, and thus reduce the time and costs needed to find new drug candidates. However, these calculations can be complex to implement and perform. Here, we introduce the software BAT.py, a Python tool that invokes the AMBER simulation package to automate the calculation of binding free energies for a protein with a series of ligands. The software supports the attach-pull-release (APR) and double decoupling (DD) binding free energy methods, as well as the simultaneous decoupling-recoupling (SDR) method, a variant of double decoupling that avoids numerical artifacts associated with charged ligands. We report encouraging initial test applications of this software both to re-rank docked poses and to estimate overall binding free energies. We also show that it is practical to carry out these calculations cheaply by using graphical processing units in common machines that can be built for this purpose. The combination of automation and low cost positions this procedure to be applied in a relatively high-throughput mode and thus stands to enable new applications in early-stage drug discovery.

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Burkholderia thailandensis E264 as a promising safe rhamnolipids’ producer towards a sustainable valorization of grape marcs and olive mill pomace

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11292-0 ◽

2021 ◽

Author(s):

Alif Chebbi ◽

Massimiliano Tazzari ◽

Cristiana Rizzi ◽

Franco Hernan Gomez Tovar ◽

Sara Villa ◽

...

Keyword(s):

Energy Source ◽

Olive Oil ◽

Low Cost ◽

Carbon Sources ◽

Burkholderia Thailandensis ◽

Rhamnolipid Production ◽

Key Points ◽

Wide Range ◽

Long Chain ◽

Olive Mill

Abstract Within the circular economy framework, our study aims to assess the rhamnolipid production from winery and olive oil residues as low-cost carbon sources by nonpathogenic strains. After evaluating various agricultural residues from those two sectors, Burkholderia thailandensis E264 was found to use the raw soluble fraction of nonfermented (white) grape marcs (NF), as the sole carbon and energy source, and simultaneously, reducing the surface tension to around 35 mN/m. Interestingly, this strain showed a rhamnolipid production up to 1070 mg/L (13.37 mg/g of NF), with a higher purity, on those grape marcs, predominately Rha-Rha C14-C14, in MSM medium. On olive oil residues, the rhamnolipid yield of using olive mill pomace (OMP) at 2% (w/v) was around 300 mg/L (15 mg/g of OMP) with a similar CMC of 500 mg/L. To the best of our knowledge, our study indicated for the first time that a nonpathogenic bacterium is able to produce long-chain rhamnolipids in MSM medium supplemented with winery residues, as sole carbon and energy source. Key points • Winery and olive oil residues are used for producing long-chain rhamnolipids (RLs). • Both higher RL yields and purity were obtained on nonfermented grape marcs as substrates. • Long-chain RLs revealed stabilities over a wide range of pH, temperatures, and salinities

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Longevity of Raw and Lyophilized Crude Urease Extracts

Sustainable Chemistry ◽

10.3390/suschem2020018 ◽

2021 ◽

Vol 2 (2) ◽

pp. 325-334

Author(s):

Neda Javadi ◽

Hamed Khodadadi Tirkolaei ◽

Nasser Hamdan ◽

Edward Kavazanjian

Keyword(s):

Crude Extract ◽

Room Temperature ◽

Low Cost ◽

Extraction Process ◽

Crude Extracts ◽

Simple Extraction ◽

Commercial Applications ◽

Stable Source ◽

The Stability ◽

The Cost

The stability (longevity of activity) of three crude urease extracts was evaluated in a laboratory study as part of an effort to reduce the cost of urease for applications that do not require high purity enzyme. A low-cost, stable source of urease will greatly facilitate engineering applications of urease such as biocementation of soil. Inexpensive crude extracts of urease have been shown to be effective at hydrolyzing urea for carbonate precipitation. However, some studies have suggested that the activity of a crude extract may decrease with time, limiting the potential for its mass production for commercial applications. The stability of crude urease extracts shown to be effective for biocementation was studied. The crude extracts were obtained from jack beans via a simple extraction process, stored at room temperature and at 4 ℃, and periodically tested to evaluate their stability. To facilitate storage and transportation of the extracted enzyme, the longevity of the enzyme following freeze drying (lyophilization) to reduce the crude extract to a powder and subsequent re-hydration into an aqueous solution was evaluated. In an attempt to improve the shelf life of the lyophilized extract, dextran and sucrose were added during lyophilization. The stability of purified commercial urease following rehydration was also investigated. Results of the laboratory tests showed that the lyophilized crude extract maintained its activity during storage more effectively than either the crude extract solution or the rehydrated commercial urease. While incorporating 2% dextran (w/v) prior to lyophilization of the crude extract increased the overall enzymatic activity, it did not enhance the stability of the urease during storage.

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Solar Thermochemical Hydrogen Production in the USA

Sustainability ◽

10.3390/su13147804 ◽

2021 ◽

Vol 13 (14) ◽

pp. 7804

Author(s):

Christoph Falter ◽

Andreas Sizmann

Keyword(s):

Hydrogen Production ◽

Large Scale ◽

Low Cost ◽

The United States ◽

Solar Irradiation ◽

Transport Sector ◽

Fossil Energy ◽

The Us ◽

The Usa ◽

Solar Thermochemical

Hydrogen produced from renewable energy has the potential to decarbonize parts of the transport sector and many other industries. For a sustainable replacement of fossil energy carriers, both the environmental and economic performance of its production are important. Here, the solar thermochemical hydrogen pathway is characterized with a techno-economic and life-cycle analysis. Assuming a further increase of conversion efficiency and a reduction of investment costs, it is found that hydrogen can be produced in the United States of America at costs of 2.1–3.2 EUR/kg (2.4–3.6 USD/kg) at specific greenhouse gas emissions of 1.4 kg CO2-eq/kg. A geographical potential analysis shows that a maximum of 8.4 × 1011 kg per year can be produced, which corresponds to about twelve times the current global and about 80 times the current US hydrogen production. The best locations are found in the Southwest of the US, which have a high solar irradiation and short distances to the sea, which is beneficial for access to desalinated water. Unlike for petrochemical products, the transport of hydrogen could potentially present an obstacle in terms of cost and emissions under unfavorable circumstances. Given a large-scale deployment, low-cost transport seems, however, feasible.

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Rotordynamic Performance of Flexure Pivot Hydrostatic Gas Bearings for Oil-Free Turbomachinery

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2720518 ◽

2007 ◽

Vol 129 (4) ◽

pp. 1020-1027 ◽

Cited By ~ 27

Author(s):

Xuehua Zhu ◽

Luis San Andrés

Keyword(s):

High Speed ◽

Low Cost ◽

Damping Ratio ◽

Extreme Temperature ◽

Gas Bearings ◽

Speed Increase ◽

Feed Pressure ◽

Motor Test ◽

Direct Stiffness ◽

Commercial Applications

Micro-turbomachinery demands gas bearings to ensure compactness, light weight, and extreme temperature operation. Gas bearings with large stiffness and damping, and preferably of low cost, will enable successful commercial applications. Presently, tests conducted on a small rotor supported on flexure pivot hydrostatic pad gas bearings (FPTPBs) demonstrate stable rotordynamic responses up to 100,000rpm (limit of the drive motor). Test rotor responses show the feed pressure raises the system critical speed (increase in bearing direct stiffness) while the viscous damping ratio decreases. Predictions correlate favorably with experimentally identified (synchronous) direct stiffness bearing force coefficients. Identified experimental gas bearing synchronous damping coefficients are 50% or less of the predicted magnitudes, though remaining relatively constant as the rotor speed increases. Tests without feed pressure show the rotor becomes unstable at ∼81krpm with a whirl frequency ratio of 20%. FPTPBs are mechanically complex and more expensive than cylindrical plain bearings. However, their enhanced stability characteristics and predictable rotordynamic performance makes them desirable for the envisioned oil-free applications in high speed micro-turbomachinery.

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Polymer-based immobilized Fe2O3–TiO2/PVP catalyst preparation method and the degradation of triclosan in treated greywater effluent by solar photocatalysis

Journal of Environmental Management ◽

10.1016/j.jenvman.2021.113305 ◽

2021 ◽

Vol 296 ◽

pp. 113305

Author(s):

Sarath Chandra Pragada ◽

Arun Kumar Thalla

Keyword(s):

Preparation Method ◽

Catalyst Preparation ◽

Solar Photocatalysis

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Solution Processed Fabrication of Perovskite Light-Emitting Diodes: Towards Low Cost and Commercial Applications

Journal of Materials Chemistry C ◽

10.1039/d1tc03385a ◽

2021 ◽

Author(s):

Jianfeng Zhang ◽

Bin Wei ◽

Lin Wang ◽

Xuyong Yang

Keyword(s):

Light Emitting Diodes ◽

Low Cost ◽

Color Purity ◽

Color Gamut ◽

Light Emitting ◽

Metal Halide Perovskite ◽

Wide Color Gamut ◽

Halide Perovskite ◽

Commercial Applications ◽

High Color Purity

Metal halide perovskite light-emitting diodes (PeLEDs) have emerged as one of the most promising candidates for next-generation high-resolution displays, due to their wide color gamut, high color purity and low-cost...

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A dsPIC Microcontroller Based System Identification of Positive Output Buck Boost Converter for Module Mismatch Application

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.785.106 ◽

2015 ◽

Vol 785 ◽

pp. 106-110

Author(s):

M.N.M. Hussain ◽

Ahmad Maliki Omar ◽

Intan Rahayu Ibrahim ◽

Kamarulazhar Daud

Keyword(s):

Direct Method ◽

Low Cost ◽

Digital Signal ◽

Solar Irradiation ◽

Identification System ◽

Pv System ◽

Partial Shading ◽

Single Output ◽

Pv Module ◽

Power Point

An identification system of multiple-input single-output (MISO) model is developed in controlling dsPIC microcontroller of positive output buck-boost (POBB) converters for module mismatch condition of photovoltaic (PV) system. In particular, the possibility of the scheme is to resolve the mismatch losses from the PV module either during shading or mismatch module occurrences. The MPPT algorithm is simplified by identification approach of indirect incorporated with a simple incremental direct method to form a combined direct and indirect (CoDId) algorithms. Irregular consumption of solar irradiation on a PV module shall step-up or step down the voltage regarding to the desired DC output voltage of POBB converter. This optimized algorithm will ensure that the PV module to kept at maximum power point (MPP), preventing power loss during module mismatch incident in PV module especially during partial shading condition. The simulation and laboratory results for PV module of polycrystalline Mitsubishi PV-AE125MF5N indicate that the proposed model and development of PV system architecture performs well, while the efficiency up to 97.7% at critical of low solar irradiance level. The controlling signal is based on low-cost embedded microcontroller of dsPIC30F Digital Signal Control (DSC).

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Effect of Different Pre-Treatments on Antinutrients and Antioxidants of Rice Bean (Vigna umbellata)

Acta Universitatis Cibiniensis Series E Food Technology ◽

10.2478/aucft-2020-0003 ◽

2020 ◽

Vol 24 (1) ◽

pp. 25-38

Author(s):

Damanpreet Kaur ◽

Kajal Dhawan ◽

Prasad Rasane ◽

Jyoti Singh ◽

Sawinder Kaur ◽

...

Keyword(s):

Antioxidant Activity ◽

Low Cost ◽

Nutrient Content ◽

Nutritional Factors ◽

Rice Bean ◽

Phytochemical Content ◽

Vigna Umbellata ◽

Commercial Applications ◽

Maximum Content ◽

Orphan Crop

AbstractRice bean (Vigna umbellata) is a legume that belongs to Vigna genus. Native to Indo-Chinese region, it is considered to be an ‘under-utilized’ or ‘orphan’ crop. Rice bean is known to possess high nutritional potential and antioxidant activity. But the use of rice bean supplementation in routine diet is limited despite its high nutritional profile due to the presence of non-nutritional factors. Thus, various pre-treatments like soaking, germination, oven roasting, sand roasting, boiling and pressure cooking at different time and temperature were carried out to reduce the anti-nutritional content of rice bean and to study its effect on antioxidant activity and phytochemical content. All the pre-treatments were able to significantly reduce the anti-nutrient content in rice bean, but germination showed the maximum reduction. Also germinated rice bean showed the maximum antioxidant potential and maximum content of total phenols, total flavonoids, vitamin C and carotenoids. Rice bean has been underutilized so far, owing to its antinutrient content and low popularity. This experiment attempted to use low cost processing to reduce the content of antinutrients and track the antioxidant content in rice bean. The concluded processing could be adopted for commercial applications for dietary supplementation.

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