scholarly journals Utilization of agroindustrial waste for biosurfactant production by native bacteria from chiapas

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Gustavo Yañez-Ocampo ◽  
Gilberto Somoza-Coutiño ◽  
Cristina Blanco-González ◽  
Arnoldo Wong-Villarreal
Keyword(s):  
Carbon Source ◽  
Room Temperature ◽  
Low Cost ◽  
Waste Cooking Oil ◽  
Industrial Wastes ◽  
Emulsification Index ◽  
Oil Hydrocarbons ◽  
Mexican State ◽  
Agroindustrial Waste ◽  
Producer Strains

AbstractIn this work, two agro-industrial wastes, namely Waste Cooking Oil (WCO) and Coffee Wastewater (CW) have been used as the carbon source for the production of biosurfactants, due to their low cost and high availability. Biosurfactant-producing bacterial isolates from the Mexican state of Chiapas were used. The selected biosurfactant-producer strains were evaluated in a liquid medium with 2% (v/v) of WCO as the carbon source. The assay was conducted in an Erlenmeyer flask containing 300 mL aliquots of mineral salt media (MSM) + residue and incubated at 100 rpm at room temperature for 96 hours. The biosurfactant produced in the samples reduced the surface tension from 50 to 30-29 mN/m. Strains A and 83 showed the maximum emulsification index at 58-59%. Strain A showed the highest biosurfactant yield with a production of 3.7 g/L in comparison with strains B, 83 and Pseudomonas aeruginosa ATCC27853. Our results suggest that the biosurfactant produced by strain A has great potential in the treatment of wastewater with a high content of fatty acids, and of soils contaminated by pesticides or oil hydrocarbons.

Development of a Starch Adhesive for Corrugated Board under Room Temperature

2011 ◽  
Vol 179-180 ◽  
pp. 812-817 ◽  
Author(s):  
Peng Luo ◽  
Yu Han Liu ◽  
Xiao Qing Zhao ◽  
Pan Pan Song ◽  
Nian Sheng Tan ◽  
...  
Keyword(s):  
Optimum Condition ◽  
Sodium Hypochlorite ◽  
Bonding Strength ◽  
High Performance ◽  
Room Temperature ◽  
Low Cost ◽  
Petroleum Products ◽  
Industrial Wastes ◽  
Manufacturing Cost ◽  
Corrugated Board

The use of starch as a renewable and biodegradable adhesive is becoming increasingly attractive because of the environmental concerns about the industrial wastes generated from petroleum products and the growing awareness of the potential deleterious consequences of greenhouse gas emissions from these activities. Starch adhesive is most extensively used in corrugated board industry because of the abundant supply, low cost, renewability, biodegradability, and ease of chemical modifications. Starch adhesive has great effect on the performance, production technology and manufacturing cost of the corrugated board. It is of great importance to develop starch adhesive with stable properties, high performance, good viscosity, fast curing speed to meet the market requirement. In this paper, oxidation of starch by sodium hypochlorite under aqueous alkaline conditions with the aid of the catalysis of nickel sulphate at room temperature was investigated. The effects of sodium hypochlorite loading and caustic soda dosage on the properties of the starch adhesive were examined. Optimization of starch oxidation is desirable to achieve the highest initial tack and bonding strength. The optimum synthesis condition was obtained. Under the optimum condition, Under the optimum condition, 98.7% of the initial tack and 11.4 N/25 mm of the bonding strength were obtained respectively.. The modified starch adhesive showed great potential for industrial application.

scholarly journals Use of Different Agroindustrial Waste and Produced Water for Biosurfactant Production

2018 ◽  
Vol 15 (1) ◽  
pp. 17-25 ◽  
Author(s):  
Everaldo Silvino dos Santos ◽  
Emilianny Rafaely Batista Magalhães ◽  
Francinaldo Leite Silva ◽  
Magna Angélica dos Santos Bezerra Sousa
Keyword(s):  
Surface Tension ◽  
Culture Medium ◽  
Produced Water ◽  
Environmental Concern ◽  
Industrial Wastes ◽  
Water Emulsion ◽  
Emulsification Index ◽  
Agroindustrial Waste ◽  
Different Temperatures ◽  
Indirect Analysis

The high and increasing environmental concern about chemical surfactants triggers attention to more eco-friendly compounds, which are capable of presenting low toxicity and biodegradable nature. This study has evaluated the emulsifying potential of broths obtained from production of rhamnolipids by Pseudomonas aeruginosa AP 029/GLVIIA using different agro-industrial wastes as carbon source, and the influence of using produced water in the culture medium then acting as an inducer. There were used residues of coconut, cashew, sugar cane, carnauba, and moringa seeds. These materials were chemically characterized and used in the production of biosurfactant broths. The emulsifying activity and the surface tension were used as indirect analysis for determining the production of rhamnolipids on biosurfactant broth. For coconut and cashew residues the pH emulsion was observed along time at different temperatures such as 4ºC, 25ºC and 40ºC The emulsification index of all broths were assessed with and without presence of produced water in the culture medium and has indicated the stability of the emulsion along time. Coconut and cashew residues showed a better stability of oil/water emulsion than the other ones, evidencing their potential surfactants. The lowest surface tension about 40 N/m and the highest contact angle (approximately 69 o) were observed for the coconut residue.

Graphene Modified Molecular Imprinting Electrochemical Sensor for Determining the Content of Dopamine

2019 ◽  
Vol 15 (6) ◽  
pp. 628-634
Author(s):  
Rong Liu ◽  
Jie Li ◽  
Tongsheng Zhong ◽  
Liping Long
Keyword(s):  
Electrochemical Sensor ◽  
Molecular Imprinting ◽  
Neurological Disorders ◽  
Room Temperature ◽  
Low Cost ◽  
Differential Pulse ◽  
Current Response ◽  
Specific Selectivity ◽  
Pulse Voltammetry

Background: The unnatural levels of dopamine (DA) result in serious neurological disorders such as Parkinson’s disease. Electrochemical methods which have the obvious advantages of simple operation and low-cost instrumentation were widely used for determination of DA. In order to improve the measurement performance of the electrochemical sensor, molecular imprinting technique and graphene have always been employed to increase the selectivity and sensitivity. Methods: An electrochemical sensor which has specific selectivity to (DA) was proposed based on the combination of a molecular imprinting polymer (MIP) with a graphene (GR) modified gold electrode. The performance and effect of MIP film were investigated by differential pulse voltammetry (DPV) and cyclic voltammetry (CV) in the solution of 5.0 ×10-3 mol/L K3[Fe(CN)6] and K4[Fe(CN)6] with 0.2 mol/L KCl at room temperature. Results: This fabricated sensor has well repeatability and stability, and was used to determine the dopamine of urine. Under the optimized experiment conditions, the current response of the imprinted sensor was linear to the concentration of dopamine in the range of 1.0×10-7 ~ 1.0×10-5 mol/L, the linear equation was I (µA) = 7.9824+2.7210lgc (mol/L) with the detection limit of 3.3×10-8 mol/L. Conclusion: In this work, a highly efficient sensor for determination of DA was prepared with good sensitivity by GR and great selectivity of high special recognization ability by molecular imprinting membrane. This proposed sensor was used to determine the dopamine in human urine successfully.

Single–atom manganese and nitrogen co-doped graphene as low-cost catalysts for the efficient CO oxidation at room temperature

2021 ◽  
Vol 536 ◽  
pp. 147809
Author(s):  
Mingming Luo ◽  
Zhao Liang ◽  
Chao Liu ◽  
Xiaopeng Qi ◽  
Mingwei Chen ◽  
...  
Keyword(s):  
Co Oxidation ◽  
Room Temperature ◽  
Low Cost ◽  
Single Atom ◽  
Doped Graphene ◽  
Co Doped

scholarly journals Room-Temperature Solution-Processed 0D/1D Bilayer Electrodes for Translucent CsPbBr3 Perovskite Photovoltaics

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1489
Author(s):  
Bhaskar Parida ◽  
Saemon Yoon ◽  
Dong-Won Kang
Keyword(s):  
Solar Cells ◽  
Indium Tin Oxide ◽  
High Performance ◽  
Room Temperature ◽  
Low Cost ◽  
Perovskite Solar Cells ◽  
Ambient Air ◽  
Plasma Damage ◽  
Temperature Solution ◽  
Ito Nanoparticles

Materials and processing of transparent electrodes (TEs) are key factors to creating high-performance translucent perovskite solar cells. To date, sputtered indium tin oxide (ITO) has been a general option for a rear TE of translucent solar cells. However, it requires a rather high cost due to vacuum process and also typically causes plasma damage to the underlying layer. Therefore, we introduced TE based on ITO nanoparticles (ITO-NPs) by solution processing in ambient air without any heat treatment. As it reveals insufficient conductivity, Ag nanowires (Ag-NWs) are additionally coated. The ITO-NPs/Ag-NW (0D/1D) bilayer TE exhibits a better figure of merit than sputtered ITO. After constructing CsPbBr3 perovskite solar cells, the device with 0D/1D TE offers similar average visible transmission with the cells with sputtered ITO. More interestingly, the power conversion efficiency of 0D/1D TE device was 5.64%, which outperforms the cell (4.14%) made with sputtered-ITO. These impressive findings could open up a new pathway for the development of low-cost, translucent solar cells with quick processing under ambient air at room temperature.

scholarly journals Enhanced Oil Removal by a Non-Toxic Biosurfactant Formulation

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 467
Author(s):  
Emília Mendes da Silva Santos ◽  
Isabela Regina Alvares da Silva Lira ◽  
Hugo Moraes Meira ◽  
Jaciana dos Santos Aguiar ◽  
Raquel Diniz Rufino ◽  
...  
Keyword(s):  
Room Temperature ◽  
Low Cost ◽  
Aeration Rate ◽  
Oil Removal ◽  
Central Composite Rotatable Design ◽  
Chemical Methods ◽  
Ph Values ◽  
Spectroscopic Analyses ◽  
New Formulation ◽  
Central Composite

In this study, a new formulation of low-cost, biodegradable, and non-toxic biosurfactant by Candida sphaerica UCP 0995 was investigated. The study was conducted in a bioreactor on an industrial waste-based medium, and a central composite rotatable design was used for optimization. The best results, namely a 25.22 mN/m reduction in surface tension, a biosurfactant yield of 10.0 g/L, and a critical micelle concentration of 0.2 g/L, were achieved in 132 h at an agitation speed of 175 rpm and an aeration rate of 1.5 vvm. Compositional and spectroscopic analyses of the purified biosurfactant by chemical methods, Fourier transform infrared spectroscopy, and nuclear magnetic resonance suggested that it is a glycolipid-type biosurfactant, and it showed no cytotoxicity in the MTT assay. The biosurfactant, submitted to different formulation methods as a commercial additive, remained stable for 120 days at room temperature. Tensioactive properties and stability were evaluated at different pH values, temperatures, and salt concentrations. The biosurfactant obtained with all formulation methods demonstrated good stability, with tolerance to wide ranges of pH, temperature and salinity, enabling application under extreme environmental conditions. Bioremediation tests were performed to check the efficacy of the isolated biosurfactant and the selected microbial species in removing oil from soil. The results demonstrated that the biosurfactant produced has promising properties as an agent for the bioremediation of contaminated soil.

scholarly journals Longevity of Raw and Lyophilized Crude Urease Extracts

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.

scholarly journals Direct measurement of the thermoelectric properties of electrochemically deposited Bi2Te3 thin films

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jose Recatala-Gomez ◽  
Pawan Kumar ◽  
Ady Suwardi ◽  
Anas Abutaha ◽  
Iris Nandhakumar ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermoelectric Properties ◽  
Bismuth Telluride ◽  
Indium Tin Oxide ◽  
Seed Layer ◽  
Room Temperature ◽  
Low Cost ◽  
Temperature Dependent ◽  
Temperature Heat ◽  
Electrochemically Deposited

Abstract The best known thermoelectric material for near room temperature heat-to-electricity conversion is bismuth telluride. Amongst the possible fabrication techniques, electrodeposition has attracted attention due to its simplicity and low cost. However, the measurement of the thermoelectric properties of electrodeposited films is challenging because of the conducting seed layer underneath the film. Here, we develop a method to directly measure the thermoelectric properties of electrodeposited bismuth telluride thin films, grown on indium tin oxide. Using this technique, the temperature dependent thermoelectric properties (Seebeck coefficient and electrical conductivity) of electrodeposited thin films have been measured down to 100 K. A parallel resistor model is employed to discern the signal of the film from the signal of the seed layer and the data are carefully analysed and contextualized with literature. Our analysis demonstrates that the thermoelectric properties of electrodeposited films can be accurately evaluated without inflicting any damage to the films.

scholarly journals Monocarborane cluster as a stable fluorine-free calcium battery electrolyte

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kazuaki Kisu ◽  
Sangryun Kim ◽  
Takara Shinohara ◽  
Kun Zhao ◽  
Andreas Züttel ◽  
...  
Keyword(s):  
Room Temperature ◽  
Coulombic Efficiency ◽  
Low Cost ◽  
Ionic Conductivities ◽  
High Energy ◽  
High Energy Density ◽  
Free Calcium ◽  
Energy Storage Devices ◽  
Storage Devices ◽  
Battery Electrolyte

AbstractHigh-energy-density and low-cost calcium (Ca) batteries have been proposed as ‘beyond-Li-ion’ electrochemical energy storage devices. However, they have seen limited progress due to challenges associated with developing electrolytes showing reductive/oxidative stabilities and high ionic conductivities. This paper describes a calcium monocarborane cluster salt in a mixed solvent as a Ca-battery electrolyte with high anodic stability (up to 4 V vs. Ca2+/Ca), high ionic conductivity (4 mS cm−1), and high Coulombic efficiency for Ca plating/stripping at room temperature. The developed electrolyte is a promising candidate for use in room-temperature rechargeable Ca batteries.

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