scholarly journals Quantitative Understanding of the Environmental Effect on B10 Copper Alloy Corrosion in Seawater

Metals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1080
Author(s):  
Yikun Cai ◽  
Yuanming Xu ◽  
Yu Zhao ◽  
Weifang Zhang ◽  
Jinghua Yao ◽  
...  
Keyword(s):  
Copper Alloy ◽  
Orthogonal Experiment ◽  
Outdoor Exposure ◽  
Influential Factors ◽  
Corrosion Process ◽  
Effect Of Temperature ◽  
Corrosion Mechanism ◽  
Natural Seawater ◽  
Experimental Conditions ◽  
Marine Corrosion

Corrosion in natural seawater is difficult to simulate in a laboratory due to the slow rate and complexity of the corrosion process which involves multiple influential factors. This paper aims to explore the quantitative effect of environmental factors on corrosion process and find the best experimental conditions which represent the actual environment and have the best acceleration effect. A new framework is followed in this paper which consists of three parts: design of experiments, outdoor and laboratory corrosion tests, and corrosion mechanism consistency confirmation. A L6(31 × 22) orthogonal experiment is designed in laboratory to study the effect of temperature, salinity, and dissolved oxygen on marine corrosion behavior of B10 copper alloy. In each test, H2O2 is added in seawater to accelerate the corrosion process. Outdoor exposure tests are also conducted in natural seawater. Results show that the corrosion process in laboratory and outdoor follows the same mechanism, in view of corrosion product and morphology, corrosion kinetics, as well as mechanical properties. With the help of quantitative analysis of the test results, a better acceleration condition can be designed.

scholarly journals Eco-Friendly Approach to Corrosion Inhibition of Copper in HNO3 Solution by the Expired Tylosin Drug

2021 ◽  
Vol 12 (4) ◽  
pp. 5116-5130
Keyword(s):  
Weight Loss ◽  
Impedance Spectroscopy ◽  
Corrosion Process ◽  
Effect Of Temperature ◽  
Corrosion Mechanism ◽  
Ac Impedance Spectroscopy ◽  
Hno3 Solution ◽  
Influence Of Temperature ◽  
Inhibition Process ◽  
Good Agreement

Expired Tylosin Drug (ETD) is examined as corrosion inhibitor for copper (Cu) dipped in 2.0 M HNO3. The study was conducted utilizing ac impedance spectroscopy (EIS), weight loss (WL), polarization, and surface checks to illustrate the importance of this ETD to prevent the corrosion process for Cu. The influence of temperature and concentration of ETD on the efficiency of inhibition were tested. The corrosion mechanism occurs when the ETD molecules block the active center in the electrode surface. Langmuir isotherm is the isotherm that is applied in the process of adsorption. The effect of temperature at various temperatures on the corrosion efficiency was investigated in case of the presence and absence of ETD. Finally, thermodynamic parameters for the inhibition process were determined. Results were of all methods used are in good agreement.

scholarly journals Corrosion Inhibition of Carbon Steel in 2.0M HCl Solution Using Novel Extract (Pulicaria undulate)

2021 ◽  
Vol 12 (5) ◽  
pp. 6415-6427
Keyword(s):  
Carbon Steel ◽  
Impedance Spectroscopy ◽  
Corrosion Process ◽  
Effect Of Temperature ◽  
Corrosion Mechanism ◽  
Ac Impedance Spectroscopy ◽  
Influence Of Temperature ◽  
Adsorption Processes ◽  
Hcl Solution ◽  
Good Agreement

Plant Pulicaria undulate (PU) extract is examined as a corrosion inhibitor for carbon steel (CS) dipped in 2.0M HCl. The study was conducted utilizing ac impedance spectroscopy (EIS), Mass loss (ML), polarization (PDP) tests, and surface checks were utilized to illustrate the importance of this PU extract to prevent the corrosion process for CS. The influence of temperature and concentration of PU on the efficacy of inhibition were tested. The corrosion mechanism occurs when the PU extract molecules block the active center in the electrode surface. Langmuir isotherm is the isotherm that is applied in the process of adsorption. The effect of temperature at various temperatures on the corrosion efficacy was investigated in case of the presence and absence of the extract. Finally, thermodynamic parameters for the activation and adsorption processes were determined. Results of all methods used were in good agreement.

Applicability of Instability Index for In vitro Protein Stability Prediction

2019 ◽  
Vol 26 (5) ◽  
pp. 339-347 ◽  
Author(s):  
Dilani G. Gamage ◽  
Ajith Gunaratne ◽  
Gopal R. Periyannan ◽  
Timothy G. Russell
Keyword(s):  
Protein Stability ◽  
Caulobacter Crescentus ◽  
Effect Of Temperature ◽  
Instability Index ◽  
Dipeptide Composition ◽  
Experimental Conditions ◽  
The Stability ◽  
Vitro Protein

Background: The dipeptide composition-based Instability Index (II) is one of the protein primary structure-dependent methods available for in vivo protein stability predictions. As per this method, proteins with II value below 40 are stable proteins. Intracellular protein stability principles guided the original development of the II method. However, the use of the II method for in vitro protein stability predictions raises questions about the validity of applying the II method under experimental conditions that are different from the in vivo setting. Objective: The aim of this study is to experimentally test the validity of the use of II as an in vitro protein stability predictor. Methods: A representative protein CCM (CCM - Caulobacter crescentus metalloprotein) that rapidly degrades under in vitro conditions was used to probe the dipeptide sequence-dependent degradation properties of CCM by generating CCM mutants to represent stable and unstable II values. A comparative degradation analysis was carried out under in vitro conditions using wildtype CCM, CCM mutants and two other candidate proteins: metallo-β-lactamase L1 and α -S1- casein representing stable, borderline stable/unstable, and unstable proteins as per the II predictions. The effect of temperature and a protein stabilizing agent on CCM degradation was also tested. Results: Data support the dipeptide composition-dependent protein stability/instability in wt-CCM and mutants as predicted by the II method under in vitro conditions. However, the II failed to accurately represent the stability of other tested proteins. Data indicate the influence of protein environmental factors on the autoproteolysis of proteins. Conclusion: Broader application of the II method for the prediction of protein stability under in vitro conditions is questionable as the stability of the protein may be dependent not only on the intrinsic nature of the protein but also on the conditions of the protein milieu.

scholarly journals Variable-rate in corn sowing for maximizing grain yield

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Eder Eujácio da Silva ◽  
Fábio Henrique Rojo Baio ◽  
Daniel Fernando Kolling ◽  
Renato Schneider Júnior ◽  
Alex Rogers Aguiar Zanin ◽  
...  
Keyword(s):  
Grain Yield ◽  
Vegetative Growth ◽  
Maximum Yield ◽  
Influential Factors ◽  
Plant Population ◽  
Seeding Density ◽  
Corn Yield ◽  
Growth Indices ◽  
Experimental Conditions ◽  
Soil Attributes

AbstractSowing density is one of the most influential factors affecting corn yield. Here, we tested the hypothesis that, according to soil attributes, maximum corn productivity can be attained by varying the seed population. Specifically, our objectives were to identify the soil attributes that affect grain yield, in order to generate a model to define the optimum sowing rate as a function of the attributes identified, and determine which vegetative growth indices can be used to predict yield most accurately. The experiment was conducted in Chapadão do Céu-GO in 2018 and 2019 at two different locations. Corn was sown as the second crop after the soybean harvest. The hybrids used were AG 8700 PRO3 and FS 401 PW, which have similar characteristics and an average 135-day cropping cycle. Tested sowing rates were 50, 55, 60, and 65 thousand seeds ha−1. Soil attributes evaluated included pH, calcium, magnesium, phosphorus, potassium, organic matter, clay content, cation exchange capacity, and base saturation. Additionally, we measured the correlation between the different vegetative growth indices and yield. Linear correlations were obtained through Pearson’s correlation network, followed by path analysis for the selection of cause and effect variables, which formed the decision trees to estimate yield and seeding density. Magnesium and apparent electrical conductivity (ECa) were the most important soil attributes for determining sowing density. Thus, the plant population should be 56,000 plants ha−1 to attain maximum yield at ECa values > 7.44 mS m−1. In addition, the plant population should be 64,800 plants ha−1 at values < 7.44 mS m−1 when magnesium levels are greater than 0.13 g kg−1, and 57,210 plants ha−1 when magnesium content is lower. Trial validation showed that the decision tree effectively predicted optimum plant population under the local experimental conditions, where yield did not significantly differ among populations.

Effect of Temperature, Reeling Speed and Pipe Tension on the Performance of Field Joint Coating During Reeling of Offshore Pipelines

2021 ◽  
Author(s):  
Rajaram Dhole ◽  
Ismael Ripoll ◽  
Sabesan Rajaratnam ◽  
Celine Jablonski
Keyword(s):  
Influential Factors ◽  
Influential Factor ◽  
Effect Of Temperature ◽  
Mechanical And Thermal Properties ◽  
Peak Strain ◽  
Element Analysis ◽  
Novel Approach ◽  
Laboratory Test Results ◽  
Coating Design ◽  
Highly Strained

Abstract Pipelines are coated with insulating material that minimizes heat losses to the environment. Reeled pipe can experience nominal bending strain in the order of 1% to 2%. Thick coating on the pipe is inherently more highly strained, because of concentrations that occur at the interface between parent coating and field joint coating. Occasionally, contractors who specialize in pipe-lay using the reeling method have experienced difficulties relating to unexpected disbondment and cracks in coating at these interfaces. Any disbonded coating is routinely identified and repaired, but it is important to understand the influential factors that could lead to this type of coating disbondment. It is known in the industry that parameters such as temperature, reeling speed and pipe tension are influential but the relative influence of the factors is not well understood. In addition, there is currently no industry code or recommended practice that proposes the strain levels that the coating could safely withstand prior to cracking. This paper addresses thermo-mechanical aspects of coating design and presents a novel approach to quantify which parameters have the largest influence. In the presented assessments, coating strain was assessed using finite element analysis. Material input was selected from a combination of typical values and specific laboratory test results for polypropylene (PP) and injection molded polypropylene (IMPP). An essential aspect was that the mechanical and thermal properties of the PP were related to temperature and strain rate. Strain rates in the coating during reeling operations were obtained from global FE models. Detailed local FE models incorporated all the material and load inputs and temperature conditions that are necessary to determine peak strain values in the coating; the peak strain values would indicate the locations of potential coating disbondment. The study is purely a strain assessment and excludes any potential for defects or delamination in the coating that could result from its manufacturing process. This strain-based study revealed that coating temperature during reeling is the most influential factor on strain level in the coating. Reeling speed and pipe tension are parameters providing secondary influences.

scholarly journals Effect of temperature on acid hydrolysis of Jerusalem artichoke as raw material for ethanol production

2013 ◽  
pp. 279-287 ◽  
Author(s):  
Radojka Razmovski ◽  
Vesna Vucurovic ◽  
Uros Miljic ◽  
Vladimir Puskas
Keyword(s):  
Hold Time ◽  
Jerusalem Artichoke ◽  
Raw Material ◽  
Effect Of Temperature ◽  
Industrial Biotechnology ◽  
Microbial Conversion ◽  
Experimental Conditions ◽  
Theoretical Yield ◽  
Renewable Raw Material ◽  
Layer Chromatography

Jerusalem artichoke (JA) is a low-requirement crop, which does not interfere with food chain, and is a promising carbon source for industrial fermentation. Microbial conversion of such a renewable raw material to useful products, such as ethanol, is an important objective in industrial biotechnology. In this study, ethanol was efficiently produced from the hydrolyzates of JA obtained at different pH values (pH 2.5, pH 3.0 and pH 3.5), temperature (120, 130, 132 and 134?C) and hold time (30 and 60 min) by Saccharomyces cerevisiae. The efficient degradation of JA by HCl under certain experimental conditions was confirmed by thin-layer chromatography. Ethanol concentration of 7.52% (w/w), which corresponds to 93.89 % of the theoretical yield is achieved by ethanol fermentation of JA hydrolyzate obtained at pH 2.5.

scholarly journals Optimization Preparation of Indium Tin Oxide Nanoparticles via Microemulsion Method Using Orthogonal Experiment

Crystals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1387
Author(s):  
Zhucheng Jiang ◽  
Ting Liu ◽  
Xiaoyu Zhai ◽  
Jiaxiang Liu
Keyword(s):  
Calcination Temperature ◽  
Tin Oxide ◽  
Indium Tin Oxide ◽  
Orthogonal Experiment ◽  
Transparent Conducting Oxide ◽  
Molar Ratio ◽  
Experimental Conditions ◽  
Microemulsion Method ◽  
Low Resistivity ◽  
Ito Nanoparticles

Indium tin oxide (ITO), an experimentally friendly transparent conducting oxide (TCO), has attracted great attention in the photoelectric field due to its intrinsically low resistivity and high transparency. In this work, the experimental conditions of preparing ITO nanoparticles using the microemulsion method were optimized by an orthogonal experiment. The optimal experimental conditions were obtained: mass ratio of the surfactant (AEO-3, MOA-5), a co-surfactant (n-propyl alcohol) of 5:3, molar ratio of indium and ammonia of 1:20, calcination temperature of 700 °C and calcination time of 4 h. Subsequently, the influence from process variables on the resistivity was researched systematically. The results demonstrated that the calcination temperature had a great effect on the resistivity; the resistivity reduced from 11.28 to 2.72 Ω·cm with the increase in the calcination temperature from 500 to 700 °C. Ultimately, ITO nanoparticles were prepared and systematically characterized under the optimal experimental conditions. The particles with a size of 60 nm were attributed to the cubic ITO crystal phase and showed low resistivity of 0.3675 Ω·cm. Significantly, ITO nanoparticles with low resistivity were obtained using the microemulsion method, which has potential application in the field of ITO nanoparticle preparation.

scholarly journals EFFECT OF TEMPERATURE, HUMIDITY AND IRRADIANCE ON SOLAR POWER GENERATION

2021 ◽  
Vol 26 (4) ◽  
pp. 113-119
Author(s):  
FRANK ONAIFO ◽  
AKPOFURE ALEXANDER OKANDEJI ◽  
OLAMIDE AJETUNMOBI ◽  
DAVID BALOGUN
Keyword(s):  
Power Generation ◽  
Solar Cells ◽  
Solar Cell ◽  
Solar Radiation ◽  
Solar Irradiance ◽  
Solar Power ◽  
Corrosion Process ◽  
Effect Of Temperature ◽  
Photovoltaic Solar Cell ◽  
Solar Power Generation

This paper studies the effect of temperature, humidity and irradiance on the power generated by a photovoltaic solar cell. This was achieved using pyranometer for determining the solar radiation, wet and dry thermometer for measuring humidity, and digital multimeter for voltage and current measurement. The result of the study show that power generation increases with increase of solar irradiance. Additionally, changes of humidity level and temperature do not significantly affect solar power generation. Furthermore, it was also observed that high temperatures and higher humidity levels accelerate the corrosion process on the solar cells which reduces the efficiency of the cells.

Optimization of Agar Preparation Based on Transparency

2021 ◽  
Vol 1033 ◽  
pp. 103-108
Author(s):  
Ying Cai ◽  
Zhan Xia Wu ◽  
Zhao Yu Zhang ◽  
Zhang Hu
Keyword(s):  
Activated Carbon ◽  
Treatment Time ◽  
Orthogonal Experiment ◽  
Economic Benefits ◽  
Experimental Results ◽  
Practical Significance ◽  
Process Conditions ◽  
Processing Temperature ◽  
Experimental Conditions ◽  
Filtration Method

To meet the requirement for high transparency of agar gel used in tissue culture, bacteriological applications, and high-quality cosmetics and food, this study on improving the transparency of agar products was carried out by using activated carbon for decolorization and perlite for aiding filtration. The results showed that the pre-coating filtration method was better than that of the mixed slurry filtration, so an orthogonal experiment optimization was conducted using the pre-coating filtration method based on the single factor experimental results. The experimental results showed that the optimal process conditions based on the transparency index were: concentration of agar of 1.30%, activated carbon dosage of 0.80%, processing temperature of 95 °C, and treatment time of 20 min. Agar products with gel transparency of 58.93% and blue-ray whiteness value of 93.82 could be obtained under these experimental conditions. The order of the factors influencing the decolorization ratio of agar was as follows: activated carbon dosage > concentration of agar > processing temperature > treatment time. The experimental results provided effective procession methods for the production enterprises based on transparency and increased economic benefits, and it was of practical significance.

The effects of temperature and pH on the embryonic development of two species of Triturus (Caudata: Salamandridae)

2007 ◽  
Vol 28 (2) ◽  
pp. 295-300 ◽  
Author(s):  
Leonardo Vignoli ◽  
Marco Bologna ◽  
Manuela D'Amen
Keyword(s):  
Mortality Rate ◽  
Embryonic Development ◽  
Effect Of Temperature ◽  
Acidic Ph ◽  
Larval Life ◽  
Experimental Conditions ◽  
Rate Of Development ◽  
Constant Ph ◽  
Effects Of Temperature ◽  
Increasing Temperature

AbstractAmphibian populations are especially sensitive to aquatic parameters, in particular during embryonic and larval life. Our aim was to test for an effect of temperature (T = 13°C, 20°C and 25°C at constant pH = 7) and pH (pH = 5.5, 7 and 8.5 at constant T= 20°C) on embryos of two species of Triturus, T. carnifex carnifex and T. italicus (Amphibia, Salamandridae) using GLM procedure. Trend of embryogenesis processes, time to hatching and rate of development have a similar effect in both species in the used range of temperature and pH. Time to hatching decreased significantly with the increasing temperature. The pH experimental conditions had no effect on T. carnifex embryos survival, while the acidic pH condition raised the mortality rate in T. italicus, whose embryos should be more vulnerable than those of T. carnifex to acidification in nature.

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