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Oil-water two-phase flow atoilfield wellheads is a common occurrence in distribution. This paper proposes using a heat transfer method to accurately measure and monitorthe total fluid volume at the wellhead. To achieve this, thermal sensors of types PT1000 and PT20, which are suitable for measuring oil-water mixed flow, are first designed. The feasibility and linearity of the sensors are simulated and calculated. Secondly, the heat transfercoefficient is computed using experimental methods and a functional relationship between the heat transfer coefficient and the flow rate is derived. Finally, the calculated results demonstrate the feasibility of using the heattransfer method to measure oil-water two-phase flow. If the water-liquid ratio (WLR) is known, the flow rate can be calculated through the functional relationship between the heat transfer coefficient and the flow rate. This method can improve the accuracy of estimating the flow rate. [ABSTRACT FROM AUTHOR]

Roasting is a key process in the production of large-leaf yellow tea (LYT). In this study, we synthesized metabolomics and electronic-tongue analysis to compare the quality of charcoal-roasted, electric-roasted and drum-roasted LYT. Charcoal-roasted LYT had the highest yellowness and redness, drum-roasted LYT had a more prominent umami and brightness, and electric roasting reduced astringency. A total of 48 metabolites were identified by metabolomics. Among these, leucocyanidin, kaempferol, luteolin-7-lactate, and apigenin-7-O-neohesperidoside might affect the brightness and yellowness. Theanine, aspartic acid, and glutamic acid contents significantly and positively correlated with umami levels, and the high retention of flavonoid glycosides and catechins in drum-roasted LYT contributed to its astringency. These findings elucidate the contribution of the roasting method to the quality of LYT and provide a theoretical basis for LYT production.

During the measurement of multiphase flow in low yield oil wells, the liquid volume will vary with the operating characteristics of the pumping unit. Using the pulsating characteristics of the up and down strokes of a pumping unit, the flow rate is measured when there is a flow rate on the up stroke, and the water content is measured when the fluid is stationary on the down stroke. In this paper, the heat transfer method is used to measure the water content of the oil water mixture during the down stroke process. At this time, the water content can be expressed as the instantaneous water content of the oil well. Firstly, the feasibility of measuring water content using heat transfer method is demonstrated theoretically, and then the temperature change of the heating probe PT300 is simulated. Finally, the actual temperature of PT300 is measured experimentally. Comparing the experimental value with the simulation value, the calculated measurement error is within 1.27 %, which indicates that the heat transfer method is feasible for measuring water content. Using the same single sensor to measure oil water two-phase flow using the pulsation characteristics of the up and down strokes of a pumping unit is a major innovation in this paper. And lays a foundation for the detection of multiphase flow using heat transfer methods. The successful implementation of the text heat transfer method for measuring water content has broken the previous situation of multiple sensor detection, simplified the structure of multiphase flow instruments, and extended the life of the instrument.

Structural lightweight aggregate concrete is currently an alternative to normal-weight concrete when thermal insulation properties are required to meet the objectives of energy efficiency and sustainability. The accurate evaluation of the thermal performance is thus essential for designing structural lightweight concrete elements. This paper aims to evaluate the thermal behavior of structural lightweight aggregate concrete, assessed through different tests methods. To this end, a vast experimental campaign was carried out involving specimens produced with several types of lightweight aggregate and different water/cement ratios. The thermal performance was established by thermal conductivity, which was determined according to a modified transient pulse method and a quasi-stationary method, and specific heat capacity, which was determined through a transient pulse method and a heat transfer method. Normal-weight concrete was also tested for comparison purposes. Experimental evidence showed that lightweight aggregate concretes with lower density are associated with up to about 50% lower thermal conductivity and higher specific heat capacity than normal-weight concrete. Moreover, the study demonstrated that the expeditious transient pulse method is suitable for assessing the thermal conductivity of this type of concrete, and that both the transient pulse method and the heat transfer method are adequate to determine the specific heat capacity. [ABSTRACT FROM AUTHOR]

Thermal flowmeters are used more and more widely in liquid flow measurement. In this paper, the mechanical shape of the thermal flowmeter is designed, and the optimal installation position of the thermal probe is determined. In the aspect of measurement mechanism research, three heating methods of the thermal probe are deduced: constant voltage heating method, constant current heating method, and constant power heating method. After reasoning, the constant current heating method is determined to be ideal, so the constant current heating method is selected to heat the speed-measuring probe in the experiment. By analyzing the power factor of convection heat transfer and residual heat source of the heating probe, it is concluded that the measurement range of the thermal flowmeter is 0.5–15 m3/d, the flow in this range is proportional to the electrical signal, and the relative error of measurement is within ±5.8%. According to the analysis of the experimental results, the thermal flowmeter has a simple mechanical structure and no redundant moving parts, which can prolong its service life when used on site. When considering industrial applications, the error may be greater than the laboratory error. [ABSTRACT FROM AUTHOR]

Serum creatinine concentration is an important clinical measure of kidney function. However, standard methods of detection, such as the Jaffe method or enzymatic assays, suffer several disadvantages, including non-specificity and procedural complexity, or high cost, respectively. In this work, we propose the use of nano-molecularly imprinted polymers (nMIPs) in conjunction with the novel Heat Transfer Method (HTM) as a promising alternative sensing platform to these existing methods for measuring serum creatinine concentration. More specifically, it is shown that creatinine-imprinted nMIPs can be produced using a solid-phase templating method, and that simple drop-casting onto a cheap, disposable substrate can be used in conjunction with HTM to detect creatinine with a limit-of-detection of (7.0 ± 0.5) μM in buffer solutions. Furthermore, the nMIPs are shown to selectively bind creatinine in comparison to several similar molecules, and the sensing platform is demonstrated to be able to detect changes in creatinine concentration in complex blood plasma samples.

Roasting is a key process in the production of large-leaf yellow tea (LYT) and substantially affects the formation of its aroma. In order to investigate the effect of roasting method on the aroma of large-leaf yellow tea and to identify the potential causes. In this study, guided by molecular sensory science, the aroma components of charcoal-roasted, electric-roasted and drum-roasted LYTs were analyzed using headspace solid phase microextraction and solvent-assisted flavor evaporation in conjunction with gas chromatography-mass spectrometry, and the data were visualized and analyzed using SMICA, SPSS and Origin. The results of quantitative descriptive analysis revealed that rice crust, burnt, corn and floral aromas were significantly different between the three samples. The results of aroma extract dilution and odor activity value analyses revealed that 2,4,5-trimethyloxazole, 1-ethylpyrrole-2-carboxaldehyde, 2-ethyl-3,5-dimethylpyrazine, 3-ethyl-2,5-dimethylpyrazine, linalool, 2,3-diethyl-5-methylpyrazine, 3,5-diethyl-2-methylpyrazine, β -damascenone, and (E)- β -ionone were the main compounds responsible for differences in the aroma of LYT subjected to different roasting methods. Aroma recombination and addition experiments verified these findings. All in all, charcoal roasting enhances the rice crust and burnt aromas of LYT, and drum roasting facilitates the presentation of floral and corn aromas. This study provides a theoretical basis for the processing of high-quality LYT. [Display omitted] • Roasting methods affect the aroma quality of LYT. • CR can significantly enhance the rice crust aroma of LYT. • CR and ER contain 2.9 × and 3.1 × more volatiles than DR. • CR and DR have the highest and lowest heterocyclic compounds. • 9 compounds identified as key differential aroma-active compounds. [ABSTRACT FROM AUTHOR]

Roasting is a key process in the production of large-leaf yellow tea (LYT). In this study, we synthesized metabolomics and electronic-tongue analysis to compare the quality of charcoal-roasted, electric-roasted and drum-roasted LYT. Charcoal-roasted LYT had the highest yellowness and redness, drum-roasted LYT had a more prominent umami and brightness, and electric roasting reduced astringency. A total of 48 metabolites were identified by metabolomics. Among these, leucocyanidin, kaempferol, luteolin-7-lactate, and apigenin-7- O -neohesperidoside might affect the brightness and yellowness. Theanine, aspartic acid, and glutamic acid contents significantly and positively correlated with umami levels, and the high retention of flavonoid glycosides and catechins in drum-roasted LYT contributed to its astringency. These findings elucidate the contribution of the roasting method to the quality of LYT and provide a theoretical basis for LYT production., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

During the measurement of multiphase flow in low yield oil wells, the liquid volume will vary with the operating characteristics of the pumping unit. Using the pulsating characteristics of the up and down strokes of a pumping unit, the flow rate is measured when there is a flow rate on the up stroke, and the water content is measured when the fluid is stationary on the down stroke. In this paper, the heat transfer method is used to measure the water content of the oil water mixture during the down stroke process. At this time, the water content can be expressed as the instantaneous water content of the oil well. Firstly, the feasibility of measuring water content using heat transfer method is demonstrated theoretically, and then the temperature change of the heating probe PT300 is simulated. Finally, the actual temperature of PT300 is measured experimentally. Comparing the experimental value with the simulation value, the calculated measurement error is within 1.27 %, which indicates that the heat transfer method is feasible for measuring water content. Using the same single sensor to measure oil water two-phase flow using the pulsation characteristics of the up and down strokes of a pumping unit is a major innovation in this paper. And lays a foundation for the detection of multiphase flow using heat transfer methods. The successful implementation of the text heat transfer method for measuring water content has broken the previous situation of multiple sensor detection, simplified the structure of multiphase flow instruments, and extended the life of the instrument., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:HongweiQin reports financial support was provided by 10.13039/501100011999Xi'an Shiyou University. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

Accurate simulation of water temperatures is crucial to the simulation of ice processes in river ice models. This study presents a quantitative assessment of uncertainties in simulating the water temperatures during river cooling and freeze-up periods. In particular, the selections of the heat transfer model and the proximity of the weather station to the study reach are investigated using the University of Alberta's River1D Ice Process model. Results show that using local versus remote weather data only had a significant impact on the performance of the full energy budget model during the river cooling period. This was mainly attributed to the large difference in the locally and remotely measured wind speeds. The full energy budget model during the freeze-up period and the linear heat transfer model were relatively insensitive to the source of weather data. The full energy budget model using local weather data was the most accurate in simulating water temperatures. When using remote weather data, the full energy budget model was generally more accurate than the linear heat transfer model in the calibration year and the two validation years, except during the cooling period of the calibration year. Neither model was able to consistently and accurately simulate the timing and magnitude of observed supercooling events. It is recommended that the full energy budget model be used whenever comprehensive weather data are available due to its overall better accuracy and less calibrated parameters than the linear heat transfer model. • Water temperature simulations during cooling and supercooling periods. • Comparison of the full energy budget and linear heat transfer models. • Comparing water temperature simulations using local versus remote weather data. • Recommended approaches to determine air-water heat fluxes and predict supercooling. [ABSTRACT FROM AUTHOR]

Modeling and prediction of deposition thickness is a key to developing crude oil transportation process. Usually, the heat transfer method has been used to calculate deposition thickness through the pipeline, but this method requires vast information and cumbersome calculations. To eliminate this problem, a feed-forward multilayer perceptron neural network (MLPNN) algorithm has been applied to predict the deposition thickness through the pipeline. We present an optimized one-layer feed-forward neural network using properties of the oil pipeline such as inlet and outlet oil temperatures, environmental (mixture of water and ethylene glycol) temperature, and oil Reynolds’ numbers. Different networks are considered and trained using 15313 data sets; the accuracy of the proposed network is validated by 5104 testing data sets. Using validating data set, the network that is having the lowest mean square error (MSE) and average absolute relative deviation percent (AARD%) and the highest regression coefficient (R2) is selected as an optimal configuration. Statistical analysis show that the artificial neural network (ANN) predictions have an excellent agreement (MSE = 9.4949e-006, AARD% = 1.0109 and R2 = 0.9999) with the heat transfer method. In the other words, accuracy of the proposed ANN model is approximately equal to the heat transfer method without required too much information and cumbersome calculations. [ABSTRACT FROM PUBLISHER]