A novel yet simple, rapid and robust thermometric endpoint titration (TET) method for the determination of sodium in various foodstuffs is described. Sodium reacts exothermically with aluminium in the presence of an e...A novel yet simple, rapid and robust thermometric endpoint titration (TET) method for the determination of sodium in various foodstuffs is described. Sodium reacts exothermically with aluminium in the presence of an excess of potassium and fluoride ions to form NaK2AlF6 (“elpasolite”). This reaction forms the basis of a ro- bust, reliable analytical procedure suitable for routine process control. The reaction of calcium under similar conditions (to form KCaAlF6) suggests that potentially, calcium may interfere in the determination of sodium in some foodstuffs. Results of an investigation suggest that at molar ratios [Ca]/[Na] < 0.85, an error of <1% of the measured value of sodium is incurred.展开更多
For noncontact optical thermometry,in contrast with fluorescence intensity ratio(FIR)technology,excitation intensity ratio(EIR)technology has been seriously limited due to low sensitivity.Moreover,by exploring all pos...For noncontact optical thermometry,in contrast with fluorescence intensity ratio(FIR)technology,excitation intensity ratio(EIR)technology has been seriously limited due to low sensitivity.Moreover,by exploring all possible temperature-dependent response,developing multimode optical thermometry is of great importance.In this work,a new Na_(2)Y_(2)TeB_(2)O_(10):Tb^(3+)phosphor is obtained by a solid-state reaction.Based on FIR and EIR models of Tb',thermometric properties are studied thoroughly.Excellent relative and absolute sensitivity(S_(R)and S_(A))are acquired due to the significant difference in emission/excitation lines in response to temperature.Meanwhile,Tb^(3+)content-dependent luminescence quenching mechanism is discussed.This study shows a feasible route for exploiting well-performing FIR-/EIR-based thermometric materials.展开更多
The effect of hydrochloric acid concentration on stainless steel (Fe6956) at temperature range 303 - 333 ± 1 K has been studied using weight loss, thermometric and electrochemical polarization techniques. The cor...The effect of hydrochloric acid concentration on stainless steel (Fe6956) at temperature range 303 - 333 ± 1 K has been studied using weight loss, thermometric and electrochemical polarization techniques. The corrosion rate of the stainless steel was found to be dependent on both temperature variation and acid concentration. The potentiostatic study showed that the active passive transition depends strongly on acid concentration while the weight loss measurements revealed that 2 M HCl at temperature 333 K had an appreciable corrosion rate which corresponds to 14.04 × 10﹣3 reaction number (RN) got from thermometric monitoring. Arrhenius equation and transition state theory were used to calculate kinetic and thermodynamic parameter such as Ea, ΔH* and ΔS*. Results obtained showed that corrosion reaction of Fe6956 in HCl is spontaneous and there is good agreement between the data got from the techniques employed.展开更多
Most of the existing building stock has a deficient energy behaviour.The thermal transmittance of fa c,ades is among those aspects which most affect this situation.In this paper,the calculation procedure with correcti...Most of the existing building stock has a deficient energy behaviour.The thermal transmittance of fa c,ades is among those aspects which most affect this situation.In this paper,the calculation procedure with correction for storage effects from ISO 9869-1 was applied to the thermometric method to determine the U-value.Due to the need for determining the number and type of layers that compose the wall to apply the calculation,a multilayer perceptron has been developed to estimate the U-value.From the different model configurations suggested,the most adequate architecture was the one with 14 nodes in the hidden layer without making transformations in the input variables.Valid results have been obtained by the multilayer perceptron for the case studies analysed from different building periods,with deviations lower than 20%between the measured value and the expected one,varying the test duration according to the thermal resistance of the wall and the temperature variations.Furthermore,it is not necessary to carry out a data post-processing for the model,so this fact simplifies and hastens the calculation procedure.展开更多
There exist a considerable variety of factors affecting the spectral emissivity of an object. The authors have designed an improved combined neural network emissivity model, which can identify the continuous spectral ...There exist a considerable variety of factors affecting the spectral emissivity of an object. The authors have designed an improved combined neural network emissivity model, which can identify the continuous spectral emissivity and true temperature of any object only based on the measured brightness temperature data. In order to improve the accuracy of approximate calculations, the local minimum problem in the algorithm must be solved. Therefore, the authors design an optimal algorithm, i.e. a hybrid chaotic optimal algorithm, in which the chaos is used to roughly seek for the parameters involved in the model, and then a second seek for them is performed using the steepest descent. The modelling of emissivity settles the problems in assumptive models in multi-spectral theory.展开更多
Optical probes hold great promise for temperature sensing owing to their attractive properties including rapid response,high spatial resolution,and remote non-invasive detection.However,the exploration of thermometric...Optical probes hold great promise for temperature sensing owing to their attractive properties including rapid response,high spatial resolution,and remote non-invasive detection.However,the exploration of thermometric probes is hindered by their low relative sensitivity(Sr)or poor structural stability in water.Herein,we propose the first example of organic-inorganic metal halides based on TPP_(3)Cu_(2)Br_(2)(TPP=triphenylphosphine)that simultaneously present excellent water resistance and sensitive temperature-dependent photoluminescence lifetime in water.Benefiting from the soft lattice induced by the organic molecule of TPP,giant thermal expansion and great lattice distortion were achieved with increasing temperature.As such,the self-trapped exciton luminescence lifetime of TPP_(3)Cu_(2)Br_(2)can be shortened to 1.9%of the initial value from 280 to 380 K,resulting in the highest Sr of 12.82%K−1 among the undoped metal halides based luminescent thermometers.Significantly,TPP_(3)Cu_(2)Br_(2)displayed extraordinary water stability with emission intensity remaining nearly unchanged after immersing in water for 15 days.Moreover,high-precision luminescence lifetime based thermal sensing in water environment was successfully conducted,which proved to be inert to the detection depth in water with a small read-out error.This work offers new routes in the exploration of novel metal halides for highly sensitive thermometric probes toward versatile application scenarios.展开更多
A comprehensive study was carried out to examine the potential of expired ivermectin drugs to inhibit corrosion on mild steel.Various techniques such as gravimetry,thermometry,potentiodynamic analysis,and computationa...A comprehensive study was carried out to examine the potential of expired ivermectin drugs to inhibit corrosion on mild steel.Various techniques such as gravimetry,thermometry,potentiodynamic analysis,and computational modelling were utilized to ascertain the drug's inhibitory efficacy.According to the results,the ivermectin drug that had reached its expiration date demonstrated noteworthy properties in inhibiting corrosion in a solution containing 2 mol/L H_(2)SO_(4).At a concentration of 500 mg/L,it exhibits approximately 90%inhibition efficiency at room temperature up to 6 h of immersion time.The findings suggest that the expired ivermectin drug can be utilized as a potential corrosion inhibitor during acid washing,which could have significant practical implications in various industries.To optimize its use as a corrosion inhibitor further research is required to investigate the performance of the drug under different conditions.展开更多
文摘A novel yet simple, rapid and robust thermometric endpoint titration (TET) method for the determination of sodium in various foodstuffs is described. Sodium reacts exothermically with aluminium in the presence of an excess of potassium and fluoride ions to form NaK2AlF6 (“elpasolite”). This reaction forms the basis of a ro- bust, reliable analytical procedure suitable for routine process control. The reaction of calcium under similar conditions (to form KCaAlF6) suggests that potentially, calcium may interfere in the determination of sodium in some foodstuffs. Results of an investigation suggest that at molar ratios [Ca]/[Na] < 0.85, an error of <1% of the measured value of sodium is incurred.
基金supported by the National Natural Science Foundation of China(No.22165031)National Undergraduate Innovation and Entrepreneurship Foundation(Nos.202210673034 and 202210673052)Program for Excellent Young Talents,Yunnan University.
文摘For noncontact optical thermometry,in contrast with fluorescence intensity ratio(FIR)technology,excitation intensity ratio(EIR)technology has been seriously limited due to low sensitivity.Moreover,by exploring all possible temperature-dependent response,developing multimode optical thermometry is of great importance.In this work,a new Na_(2)Y_(2)TeB_(2)O_(10):Tb^(3+)phosphor is obtained by a solid-state reaction.Based on FIR and EIR models of Tb',thermometric properties are studied thoroughly.Excellent relative and absolute sensitivity(S_(R)and S_(A))are acquired due to the significant difference in emission/excitation lines in response to temperature.Meanwhile,Tb^(3+)content-dependent luminescence quenching mechanism is discussed.This study shows a feasible route for exploiting well-performing FIR-/EIR-based thermometric materials.
文摘The effect of hydrochloric acid concentration on stainless steel (Fe6956) at temperature range 303 - 333 ± 1 K has been studied using weight loss, thermometric and electrochemical polarization techniques. The corrosion rate of the stainless steel was found to be dependent on both temperature variation and acid concentration. The potentiostatic study showed that the active passive transition depends strongly on acid concentration while the weight loss measurements revealed that 2 M HCl at temperature 333 K had an appreciable corrosion rate which corresponds to 14.04 × 10﹣3 reaction number (RN) got from thermometric monitoring. Arrhenius equation and transition state theory were used to calculate kinetic and thermodynamic parameter such as Ea, ΔH* and ΔS*. Results obtained showed that corrosion reaction of Fe6956 in HCl is spontaneous and there is good agreement between the data got from the techniques employed.
文摘Most of the existing building stock has a deficient energy behaviour.The thermal transmittance of fa c,ades is among those aspects which most affect this situation.In this paper,the calculation procedure with correction for storage effects from ISO 9869-1 was applied to the thermometric method to determine the U-value.Due to the need for determining the number and type of layers that compose the wall to apply the calculation,a multilayer perceptron has been developed to estimate the U-value.From the different model configurations suggested,the most adequate architecture was the one with 14 nodes in the hidden layer without making transformations in the input variables.Valid results have been obtained by the multilayer perceptron for the case studies analysed from different building periods,with deviations lower than 20%between the measured value and the expected one,varying the test duration according to the thermal resistance of the wall and the temperature variations.Furthermore,it is not necessary to carry out a data post-processing for the model,so this fact simplifies and hastens the calculation procedure.
文摘There exist a considerable variety of factors affecting the spectral emissivity of an object. The authors have designed an improved combined neural network emissivity model, which can identify the continuous spectral emissivity and true temperature of any object only based on the measured brightness temperature data. In order to improve the accuracy of approximate calculations, the local minimum problem in the algorithm must be solved. Therefore, the authors design an optimal algorithm, i.e. a hybrid chaotic optimal algorithm, in which the chaos is used to roughly seek for the parameters involved in the model, and then a second seek for them is performed using the steepest descent. The modelling of emissivity settles the problems in assumptive models in multi-spectral theory.
基金supported by the National Natural Science Foundation of China(Nos.22135008,22275188,U22A20398,12104455)Natural Science Foundation of Fujian Province(Nos.2023I0032,2022J05092).
文摘Optical probes hold great promise for temperature sensing owing to their attractive properties including rapid response,high spatial resolution,and remote non-invasive detection.However,the exploration of thermometric probes is hindered by their low relative sensitivity(Sr)or poor structural stability in water.Herein,we propose the first example of organic-inorganic metal halides based on TPP_(3)Cu_(2)Br_(2)(TPP=triphenylphosphine)that simultaneously present excellent water resistance and sensitive temperature-dependent photoluminescence lifetime in water.Benefiting from the soft lattice induced by the organic molecule of TPP,giant thermal expansion and great lattice distortion were achieved with increasing temperature.As such,the self-trapped exciton luminescence lifetime of TPP_(3)Cu_(2)Br_(2)can be shortened to 1.9%of the initial value from 280 to 380 K,resulting in the highest Sr of 12.82%K−1 among the undoped metal halides based luminescent thermometers.Significantly,TPP_(3)Cu_(2)Br_(2)displayed extraordinary water stability with emission intensity remaining nearly unchanged after immersing in water for 15 days.Moreover,high-precision luminescence lifetime based thermal sensing in water environment was successfully conducted,which proved to be inert to the detection depth in water with a small read-out error.This work offers new routes in the exploration of novel metal halides for highly sensitive thermometric probes toward versatile application scenarios.
基金the financial support provided by Madhya Pradesh–Council of Science&Technology under the Project Scheme[Reference No.2707/CST/R&D/Phy.&Engg and Pharmacy/2022]
文摘A comprehensive study was carried out to examine the potential of expired ivermectin drugs to inhibit corrosion on mild steel.Various techniques such as gravimetry,thermometry,potentiodynamic analysis,and computational modelling were utilized to ascertain the drug's inhibitory efficacy.According to the results,the ivermectin drug that had reached its expiration date demonstrated noteworthy properties in inhibiting corrosion in a solution containing 2 mol/L H_(2)SO_(4).At a concentration of 500 mg/L,it exhibits approximately 90%inhibition efficiency at room temperature up to 6 h of immersion time.The findings suggest that the expired ivermectin drug can be utilized as a potential corrosion inhibitor during acid washing,which could have significant practical implications in various industries.To optimize its use as a corrosion inhibitor further research is required to investigate the performance of the drug under different conditions.
