Sliced boiled chicken is a kind of Chinese food which has a history of more than two hundred years.At the very beginning,it was offered to customers as a kind of fast food.After two centuries’development,it has becom...Sliced boiled chicken is a kind of Chinese food which has a history of more than two hundred years.At the very beginning,it was offered to customers as a kind of fast food.After two centuries’development,it has become a cultural symbol of Guangdong region.In other words,the significance of sliced boiled chicken has transcended the food itself.It is an essential part of Cantonese life.Because it is a dish that is relatively easy to cook,we can see sliced boiled chicken everywhere in Guangdong Province,China.No matter in the city or in the countryside,in upscale restaurants or in fast food restaurants,if you want,you can easily find a place to enjoy the delicacy of sliced boiled chicken.However,most of the people just know to eat sliced boiled chicken.Only a small part of them will notice the history behind this dish.At the same time,though this dish is seen as a cultural symbol,most people just see it as a money making tool which greatly disturbs its development.展开更多
Cassava root is shortly preserved after harvesting due to its tanning and rapid physiological decomposition. Consequently, the commercial value is reduced and the craving of its finishes products. With an aim of impro...Cassava root is shortly preserved after harvesting due to its tanning and rapid physiological decomposition. Consequently, the commercial value is reduced and the craving of its finishes products. With an aim of improving physiological quality, post harvest food value “the effects of bleaching and conservation in silo-pits were evaluated. Four (04) varieties of cassava: Bocou1, Bocou2, Bocou3 and Yavo were collected fresh and healthy in 13 months of maturity. They were subjected to a bleaching (65°C /15 - 30 s) followed by a kinetic conservation (7 days of intervals) in silo-pit (1 × 0.6 × 0.5 m). Results show that Bocou2 variety has the high proteins content (2.64% ± 0.01%), followed by hydrocyanic acid (8.21 ± 0.01 mg/100 g) and total carotenoids (26.7 μg/100 g). The conservation influences positively the protein content, reducing sugars content, the dries matter content and the total phenolic compounds for all the varieties excluded Bocou2 variety whose protein content drops. As regard of the fat contents, a weak increase is observed. The sensory analysis reveals that the boiled cassava of the Yavo variety is more appreciated followed by Bocou1 variety. Concerning the Attiéké, Bocou3 variety gives the more appreciated dish followed by the Yavo variety. In conclusion, the silo-pit conservation after bleaching improves the physiological quality of the cassava and the sensory taste even during 14 days. This study has a huge impact of reducing the post harvests losses and increases the commercial value of cassava in the world.展开更多
Changes in tissue structures, rheological properties of cross- and vertical section boiled abalone meat were studied in relation to boiling time. The adductor muscle of abalone Haliotis discus which was removed from t...Changes in tissue structures, rheological properties of cross- and vertical section boiled abalone meat were studied in relation to boiling time. The adductor muscle of abalone Haliotis discus which was removed from the shell, was boiled for 1, 2, and 3 h, respectively. Then it was cut up and separated into cross- and vertical section meat. When observed by a light microscope and a scanning electron microscope, structural changes in the myofibrils were greatest in the cross section meat compared with the vertical section meat. When boiling time was increased from 1 h to 3 h, the instantaneous modulus E 0 and rupture strength of both section meat decreased gradually with increased boiling time, and no significant differences were observed between these two section meat for the same boiling time. When boiled for 1 h, the relaxation time of cross section meat was much longer than that of vertical section meat. There were no significant changes in the relaxation time of vertical section for different boiling time, but the relaxation time of cross section meat was reduced gradually with increasing boiling time. These results confirmed that the difference in rheological properties between the cross- and vertical section meat was mainly due to the denaturation level of myofibrils when heated for 1 h, as well as due to the changes in the amount of denatured proteins, and the manner in which the inner denatured protein components weve exchanged after boiling time was increased from 1 h to 3 h.展开更多
Evaluation of dietary fiber and fatty acid composition of boiled, roasted, fermented and germinated breadnut seed flour was investigated. The seeds were dehulled and washed. It was divided into four equal parts for di...Evaluation of dietary fiber and fatty acid composition of boiled, roasted, fermented and germinated breadnut seed flour was investigated. The seeds were dehulled and washed. It was divided into four equal parts for different processing techniques: boiled, roasted, germinated and fermented. They were analyzed for dietary fibre and fatty acid composition using standard methods. Data were subjected to statistical analysis using Statistical Product for Service Solution (SPSS) version 23.0. Values were expressed as means and standard deviation, Duncan multiple range test was used in separating the means at 95% confidence interval. Dietary fibre composition showed that breadnut seed flours range from 4.94%(fermented breadnut seed flour) to 5.42%(roasted breadnut seed flour). Fatty acid profile showed that breadnut seed flours contain a greater amount of non-essential fatty acids which were highly significant (p < 0.05) in oleic acid (57.93%) for roasted breadnut seed flour followed by linoleic acid (25.76%) in fermented breadnut flour. Stearic acid was the only prominent non-essential fatty acid in the breadnut seed flour and ranged from 4.40%(fermented breadnut seed flour) to 6.27%(germinated breadnut seed flour). The study revealed that all the processed breadnut seed flours have appreciable quantities of dietary fibre and essential fatty acids than non-essential fatty acids. Breadnut seed should be recommended in wheat substitution in bakery industry and culinary uses. It is also recommended for weight loss program.展开更多
Last Sunday,I felt very hungry when I got up late.There was no food in the fridge,so l decided to cook noodles for me①.First,I filled the pot with water and put it on the stove.I waited patiently for the water to boi...Last Sunday,I felt very hungry when I got up late.There was no food in the fridge,so l decided to cook noodles for me①.First,I filled the pot with water and put it on the stove.I waited patiently for the water to boil.Then,I put the noodles into the boiling water.Next,I added some vegetables,an egg,and a little salt.展开更多
In modern engineering,enhancing boiling heat transfer efficiency is crucial for optimizing energy use and several industrial processes involving different types of materials.This study explores the enhancement of pool...In modern engineering,enhancing boiling heat transfer efficiency is crucial for optimizing energy use and several industrial processes involving different types of materials.This study explores the enhancement of pool boiling heat transfer potentially induced by combining perforated copper particles on a heated surface with a sodium dodecyl sulfate(SDS)surfactant in saturated deionized water.Experiments were conducted at standard atmospheric pressure,with heat flux ranging from 20 to 100 kW/m2.The heating surface,positioned below the layer of freely moving copper beads,allowed the particle layer to shift due to liquid convection and steam nucleation.The study reports on the influence of copper bead diameter(2,3,4,and 5 mm),particle quantity,arrangement,and SDS concentration(20,200,and 500 ppm).It is shown that the combination of 5 mm particles and a 500 ppm SDS concentration can yield a remarkable 139%improvement in heat transfer efficiency.As demonstrated by direct flow visualization,bubble formation occurs primarily in the gaps between the particles and the heated surface,with the presence of SDS reducing bubble size and accelerating bubble detachment.展开更多
This study investigates the flow boiling heat transfer coefficient and pressure gradient of refrigerant R410A inmicro-channel flat tubes.Experiments were conducted at saturation temperatures ranging from 25℃ to 30℃,...This study investigates the flow boiling heat transfer coefficient and pressure gradient of refrigerant R410A inmicro-channel flat tubes.Experiments were conducted at saturation temperatures ranging from 25℃ to 30℃,mass fluxes between 198 and 305 kg/m^(2)s,and heat fluxes from 9.77 to 20.18 kW/m^(2),yielding 99 sets of local heat transfer coefficient data.The results show that increasing heat flux and mass flux enhances the heat transfer coefficient,although the rate of enhancement decreases with increasing vapor quality.Conversely,higher saturation temperatures slightly reduce the heat transfer coefficient.Additionally,the experimental findings reveal discrepancies in the accuracy of existing pressure drop and heat transfer coefficient prediction models under the studied conditions.This study recommends using the Kimand Mudawar correlation to predict pressure gradients within the tested range,with aMean Error(ME)of−5.24%observed in this study.For heat transfer coefficients,the Cooper and Kandlikar correlations are recommended,achieving a Mean Absolute Error(MAE)of approximately 22%.This research provides value for performance prediction and parameter selection of micro-channel technology in broader application scenarios within heating,ventilation and air-conditioning fields.展开更多
In this study,the flow boiling characteristics of R1234yf in parallel microchannels were experimentally investigated.The experiments were conducted with heat flux from 0 to 550 kW/m^(2),mass flux of 434,727,and 1015 k...In this study,the flow boiling characteristics of R1234yf in parallel microchannels were experimentally investigated.The experiments were conducted with heat flux from 0 to 550 kW/m^(2),mass flux of 434,727,and 1015 kg/(m2 s),saturation temperatures of 293,298,and 303 K,and inlet sub-cooling of 5,10,and 15 K.The analysis of the experimental results provides the following conclusions:a reduced mass flux and lower subcooling correspond to a diminished degree of superheat at the boiling inception wall;conversely,an elevated saturation temperature results in a reduced amount of superheat at the boiling inception wall.Furthermore,an increase in sub-cooling and saturation temperature will enhance heat transfer efficiency.The wall temperature is mostly influenced by variations in saturation temperature and is minimally related to changes in mass flux and subcooling degree.An increase in mass flux results in a greater pressure drop attributed to heightened frictional pressure loss.The variation in pressure drop with respect to sub-cooling is minimal,while an increased saturation temperature correlates with a reduced pressure drop due to the formation of smaller bubbles and lowered frictional pressure loss at high saturation pressures.This study thoroughly examines and summarizes the effects of mass flow rate,saturation temperature,and subcooling on the flow-boiling heat transfer and pressure drop characteristics of R1234yf.Furthermore,the new correlation has 93.42%of the predicted values fall within a 15%mean absolute error,exhibiting a mean absolute error of 5.75%.It provides a superior method for predicting the flow-boiling heat transfer coefficients of R1234yf in the heat sink of parallel microchannels compared to existing correlations.展开更多
This research explores the characteristics of boiling in inclined pipes,a domain of great importance in engineering.Employing an experimental visualization technique,the boiling dynamics of deionizedwater are examined...This research explores the characteristics of boiling in inclined pipes,a domain of great importance in engineering.Employing an experimental visualization technique,the boiling dynamics of deionizedwater are examined at varying inclination angles,paying special attention to the emerging flow patterns.The findings demonstrate that the inclination angle significantly impacts flow pattern transitions within the 0°to 90°range.As the heat flux rises,bubbles form in the liquid.The liquid’s inertia extends the bubble-wall contact time,thereby delaying the onset of bulk bubble flow.Beyond a 90°inclination,however,the patterning behavior is more influenced by the fluid velocity.At low speeds,incomplete pipe filling results in a large liquid plug hindering flow,while high speeds lead to full pipe filling.In general,gravity,inertia,buoyancy forces,and capillary forces are themain influential factors in the considered problem.However,an analysis of the heat transfer coefficient and boiling curve for different inclination angles reveals that the observed variations are essentially due to corresponding changes in the flow pattern.Finally,an optimal mass flux and inclination angle,able to minimize total entropy generation and improve heat transfer efficiency,are determined by means of an entropy generation analysis.展开更多
Flow boiling in open microchannels offers highly efficient heat transfer performance and has attracted increasing attention in the fields of heat transfer and thermalmanagement of electronic devices in recent years.Ho...Flow boiling in open microchannels offers highly efficient heat transfer performance and has attracted increasing attention in the fields of heat transfer and thermalmanagement of electronic devices in recent years.However,the continuous rise in power density of electronic components imposesmore stringent requirements on the heat transfer capability of microchannel flow boiling.HFE-7100,a dielectric coolant with favorable thermophysical properties,has become a focal point of research for enhancing flow boiling performance in open microchannels.The flow boiling heat transfer performance ofHFE-7100 was investigated in this study by fabricating micro-nano composite structures on the bottom surface of open microchannels using laser ablation technology.Based on visualization results,a comparative analysis was conducted on the bubble dynamics and flow pattern characteristics of HFE-7100 flow boiling in micronano structured open microchannels(MNSOMC)and smooth-surface open microchannels(SSOMC),to elucidate the enhancement mechanism of micro-nano structures on flow boiling heat transfer in open microchannels.The results indicate that the surface structures and strong wettability of MNSOMC accelerated bubble nucleation and departure.Moreover,bubbles in the channel tended to coalesce along the flow direction,forming elongated slug bubbles with high aspect ratios,which enabled efficient thin film evaporation in conjunction with intense nucleate boiling,thereby significantly enhancing flow boiling heat transfer.Under the experimental conditions of this study,the maximum enhancements in the heat transfer coefficient(HTC)and critical heat flux(CHF)of HFE-7100 inMNSOMC were 33.4%and 133.1%,respectively,with the CHF reaching up to 1542.3 kW⋅m^(−2).Furthermore,due to the superior wettability and capillary wicking capability of the micro-nano composite structures,the significant enhancement in flow boiling heat transfer was achieved without incurring a noticeable pressure drop penalty.展开更多
The evaporation ofmicrometer and millimeter liquid drops,involving a liquid-to-vapor phase transition accompanied by mass and energy transfer through the liquid-vapor interface,is encountered in many natural and indus...The evaporation ofmicrometer and millimeter liquid drops,involving a liquid-to-vapor phase transition accompanied by mass and energy transfer through the liquid-vapor interface,is encountered in many natural and industrial processes as well as in numerous engineering applications.Therefore,understanding and predicting the dynamics of evaporating flows have become of primary importance.Recent efforts have been addressed using the method of Smoothed Particle Hydrodynamics(SPH),which has proven to be very efficient in correctly handling the intrinsic complexity introduced by the multiscale nature of the evaporation process.This paper aims to provide an overview of published work on SPH-based simulations related to the evaporation of drops suspended in static and convective environments and impacting on heated solid surfaces.After a brief theoretical account of the main ingredients necessary for the modeling of drop evaporation,the fundamental aspects of SPH are revisited along with the various existing formulations that have been implemented to address the challenges imposed by the physics of evaporating flows.In the following sections,the paper summarizes the results of SPH-based simulations of drop evaporation and ends with a few comments on the limitations of the current state-of-the-art SPHsimulations and future lines of research.展开更多
Ingredients: 125 grams of chicken breast meat, 125 grams of pork tenderloin, edible fungus, tremella, winter bamboo shoots and cucumbers, 100 grams of edible oil, 100 grams of corn starch and an optional amount of soy...Ingredients: 125 grams of chicken breast meat, 125 grams of pork tenderloin, edible fungus, tremella, winter bamboo shoots and cucumbers, 100 grams of edible oil, 100 grams of corn starch and an optional amount of soy sauce, cooking wine, vinegar, salt and MSG, soup stock, eggs, water soaked from Chinese prickly ashes, soya bean paste, scallions, ginger roots and garlic to taste. Directions: 1. Slice the chicken breast meat, the pork tenderloin, bamboo shoots and cucumbers. Add the chicken meat, egg whites and corn starch. Marinate the tenderloin in the Chinese prickly展开更多
This is a story of a young man named Owen, who lived in a faraway country, and a king, who was getting old and needed to find a successor(1). The king had thought of a way to find a successor who would have courage an...This is a story of a young man named Owen, who lived in a faraway country, and a king, who was getting old and needed to find a successor(1). The king had thought of a way to find a successor who would have courage and be honest.展开更多
The increasingly stringent emission regulations and fuel consumption requirements have elevated the demands of internal combustion engines with higher fuel efficiency and lower emissions.It has been widely demonstrate...The increasingly stringent emission regulations and fuel consumption requirements have elevated the demands of internal combustion engines with higher fuel efficiency and lower emissions.It has been widely demonstrated that fash boiling spray can generate shorter and wider spray with improved atomization and evaporation to promote a better air-fuel mixing process.In this study,macroscopic(far-field)spray morphologies and primary breakup(near-field)characteristics of a two-hole gasoline direct injection injector are investigated under non-flash boiling and flash boiling conditions.High speed macroscopic and microscopic imaging was used to capture the overall spray structure and near-field characteristics,respectively.N-Hexane is used as the test fuel with the injection pressure ranging from 10 MPa up to 40 MPa.For sub-cooled liquid fuel sprays,increasing fuel pressure contributes to enhanced fuel atomization and evaporation.Evident collapses occurred under fare flash boiling conditions,and higher injection pressure weakened this phenomenon since the spray cone angle decreased due to a higher injection velocity.展开更多
The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization origi...The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the Yanshanian.Isotope compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou complex.Ore-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage II-3.These systematic changes are closely related to the processes of mineral precipitation and fluid evolution.Sulfide precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur fugacity.Condensation of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native tellurium.Based on these hypotheses,this paper present a polyphase metallogenic model as follow.During the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early ores.During the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit.展开更多
The regime of horizontal subcooled film boiling is characterized by the formation of a thin layer of vapor coveringthe surface of a flat horizontal heater. Based on the equations of motion of a viscous incompressible ...The regime of horizontal subcooled film boiling is characterized by the formation of a thin layer of vapor coveringthe surface of a flat horizontal heater. Based on the equations of motion of a viscous incompressible fluid and theequation of heat transfer, the stability of such a vapor film is investigated. The influence of the modulation of thegravity field caused by vertical vibrations of the heater of finite frequency, as well as a constant electric fieldapplied normal to the surface of the heater, is taken into account. It is shown that in the case of a thick vaporfilm, the phase transition has a little effect on the thresholds for the occurrence of parametric instability in thesystem and its transformation into the most dangerous one. At the same time, the electric field contributes toan increase in these thresholds. It was found that the effect of vibrations on the stabilization of non-parametricinstability in the system is possible only in a narrow region of the parameter space where long-wave damped disturbances exist and consists of reducing the critical heat flux of stabilization. A vapor film stabilized in this waycan be destroyed due to the development of parametric instability. In contrast to the case of a thick vapor layer,the threshold for the onset of parametric instability for thin films largely depends on the value of subcooling in thesystem. In addition, this threshold decreases with increasing electric field strength. For a vapor film ten micronsthick, the instability threshold can be reduced by a factor of three or more by applying an electric field of aboutthree million volts per meter.展开更多
Flash boiling atomization(FBA)is a promising approach for enhancing spray atomization,which can generate a fine and more evenly distributed spray by increasing the fuel injection temperature or reducing the ambient pr...Flash boiling atomization(FBA)is a promising approach for enhancing spray atomization,which can generate a fine and more evenly distributed spray by increasing the fuel injection temperature or reducing the ambient pressure.However,when the outlet speed of the nozzle exceeds 400 m/s,investigating high-speed flash boiling atomization(HFBA)becomes quite challenging.This difficulty arises fromthe involvement ofmany complex physical processes and the requirement for a very fine mesh in numerical simulations.In this study,an HFBA model for gasoline direct injection(GDI)is established.This model incorporates primary and secondary atomization,as well as vaporization and boilingmodels,to describe the development process of the flash boiling spray.Compared to lowspeed FBA,these physical processes significantly impact HFBA.In this model,the Eulerian description is utilized for modeling the gas,and the Lagrangian description is applied to model the droplets,which effectively captures the movement of the droplets and avoids excessive mesh in the Eulerian coordinates.Under various conditions,numerical solutions of the Sauter mean diameter(SMD)for GDI show good agreement with experimental data,validating the proposed model’s performance.Simulations based on this HFBA model investigate the influences of fuel injection temperature and ambient pressure on the atomization process.Numerical analyses of the velocity field,temperature field,vapor mass fraction distribution,particle size distribution,and spray penetration length under different superheat degrees reveal that high injection temperature or low ambient pressure significantly affects the formation of small and dispersed droplet distribution.This effect is conducive to the refinement of spray particles and enhances atomization.展开更多
In this paper,a new approach called the Eulerian species method was proposed for simulating the convective and/or boiling heat transfer of nanofluids.The movement of nanoparticles in nanofluids is tracked by the speci...In this paper,a new approach called the Eulerian species method was proposed for simulating the convective and/or boiling heat transfer of nanofluids.The movement of nanoparticles in nanofluids is tracked by the species transport equation,and the boiling process of nanofluids is computed by the Eulerian multiphase method coupled with the RPI boiling model.The validity of the species transport equation for simulating nanoparticles movement was verified by conducting a simulation of nanofluids convective heat transfer.Simulation results of boiling heat transfer of nanofluids were obtained by using the commercial CFD software ANSYS Fluent and compared with experimental data and results from another numerical method(Eulerian three-phase model).Good agreement with experimental data was achieved,and it was proved the Eulerian species method is better than the Eulerian three-phase model since it can give better simulation results with higher accuracy but needs fewer computation resources.展开更多
To date,using biphilic surfaces is one of the most promising methods for enhancing heat transfer and critical heat flux during boiling simultaneously.However,most of studies on the effect of biphilic surfaces on boili...To date,using biphilic surfaces is one of the most promising methods for enhancing heat transfer and critical heat flux during boiling simultaneously.However,most of studies on the effect of biphilic surfaces on boiling perfor-mance have been carried out under atmospheric pressure conditions.In this context,the issues of heat transfer enhancement and stabilization of the boiling process at subatmospheric pressures are particularly critical due to the interesting characteristics of boiling heat transfer and bubble dynamics at subatmospheric pressures and their practical significance including aerospace applications.This paper investigates the effect of the pitch size between hydrophobic spots on a biphilic surface on heat transfer and bubble dynamics during boiling at subatmospheric pressures(from 11.2 kPa up to atmospheric pressure).The data analysis using infrared thermography demonstrated that the maximum heat transfer rate was achieved on a surface with a uniform pitch size(6 mm)at all pressures.In this case,the heat transfer enhancement,compared a bare surface,reached 3.4 times.An analysis of the departure diameters of bubbles based on high-speed visualization indicated that the optimal configuration of the biphilic surface corresponds to the pitch size equal to the bubble departure diameter.Using high-speed visualization also demonstrated that an early transition to film boiling was evident for configurations with a very high density of hydrophobic spots(pitch size of 2 mm).展开更多
Boiling heat transfer,as an efficient heat transfer approach,that can absorb a large amount of latent heat during the vaporization,is especially suitable for heat transfer occasions with high heat flux demands.Experim...Boiling heat transfer,as an efficient heat transfer approach,that can absorb a large amount of latent heat during the vaporization,is especially suitable for heat transfer occasions with high heat flux demands.Experimental studies show that the surface tension coefficient of pure water can be reduced sharply(up to 25%)when it is magnetized by amagnetic field applied externally.In this paper,magnetized water(MW)was used as the work fluid to conduct boiling heat transfer experiments,to explore the influence of magnetization on the boiling characteristics of pure water.The electromagnetic device was used to magnetize water,and then the MW was used as the work-fluid of boiling heat transfer experiments,the bubble dynamic behavior of the MW boiling was captured by a video camera,and the characteristics andmechanism were analyzed.It was found that at the same conditions,the boiling of MW can produce more vapor bubbles of smaller size than the water without magnetization,which leads to a higher heat-transfer efficiency.This indicates that magnetization can enhance the boiling heat transfer of pure water.Furthermore,the thermal conditions required by magnetized water when the boiling is started are lower than the non-magnetized water boiling,whichmeans the earlier start of nucleate pool boiling when using the MW.展开更多
文摘Sliced boiled chicken is a kind of Chinese food which has a history of more than two hundred years.At the very beginning,it was offered to customers as a kind of fast food.After two centuries’development,it has become a cultural symbol of Guangdong region.In other words,the significance of sliced boiled chicken has transcended the food itself.It is an essential part of Cantonese life.Because it is a dish that is relatively easy to cook,we can see sliced boiled chicken everywhere in Guangdong Province,China.No matter in the city or in the countryside,in upscale restaurants or in fast food restaurants,if you want,you can easily find a place to enjoy the delicacy of sliced boiled chicken.However,most of the people just know to eat sliced boiled chicken.Only a small part of them will notice the history behind this dish.At the same time,though this dish is seen as a cultural symbol,most people just see it as a money making tool which greatly disturbs its development.
文摘Cassava root is shortly preserved after harvesting due to its tanning and rapid physiological decomposition. Consequently, the commercial value is reduced and the craving of its finishes products. With an aim of improving physiological quality, post harvest food value “the effects of bleaching and conservation in silo-pits were evaluated. Four (04) varieties of cassava: Bocou1, Bocou2, Bocou3 and Yavo were collected fresh and healthy in 13 months of maturity. They were subjected to a bleaching (65°C /15 - 30 s) followed by a kinetic conservation (7 days of intervals) in silo-pit (1 × 0.6 × 0.5 m). Results show that Bocou2 variety has the high proteins content (2.64% ± 0.01%), followed by hydrocyanic acid (8.21 ± 0.01 mg/100 g) and total carotenoids (26.7 μg/100 g). The conservation influences positively the protein content, reducing sugars content, the dries matter content and the total phenolic compounds for all the varieties excluded Bocou2 variety whose protein content drops. As regard of the fat contents, a weak increase is observed. The sensory analysis reveals that the boiled cassava of the Yavo variety is more appreciated followed by Bocou1 variety. Concerning the Attiéké, Bocou3 variety gives the more appreciated dish followed by the Yavo variety. In conclusion, the silo-pit conservation after bleaching improves the physiological quality of the cassava and the sensory taste even during 14 days. This study has a huge impact of reducing the post harvests losses and increases the commercial value of cassava in the world.
文摘Changes in tissue structures, rheological properties of cross- and vertical section boiled abalone meat were studied in relation to boiling time. The adductor muscle of abalone Haliotis discus which was removed from the shell, was boiled for 1, 2, and 3 h, respectively. Then it was cut up and separated into cross- and vertical section meat. When observed by a light microscope and a scanning electron microscope, structural changes in the myofibrils were greatest in the cross section meat compared with the vertical section meat. When boiling time was increased from 1 h to 3 h, the instantaneous modulus E 0 and rupture strength of both section meat decreased gradually with increased boiling time, and no significant differences were observed between these two section meat for the same boiling time. When boiled for 1 h, the relaxation time of cross section meat was much longer than that of vertical section meat. There were no significant changes in the relaxation time of vertical section for different boiling time, but the relaxation time of cross section meat was reduced gradually with increasing boiling time. These results confirmed that the difference in rheological properties between the cross- and vertical section meat was mainly due to the denaturation level of myofibrils when heated for 1 h, as well as due to the changes in the amount of denatured proteins, and the manner in which the inner denatured protein components weve exchanged after boiling time was increased from 1 h to 3 h.
文摘Evaluation of dietary fiber and fatty acid composition of boiled, roasted, fermented and germinated breadnut seed flour was investigated. The seeds were dehulled and washed. It was divided into four equal parts for different processing techniques: boiled, roasted, germinated and fermented. They were analyzed for dietary fibre and fatty acid composition using standard methods. Data were subjected to statistical analysis using Statistical Product for Service Solution (SPSS) version 23.0. Values were expressed as means and standard deviation, Duncan multiple range test was used in separating the means at 95% confidence interval. Dietary fibre composition showed that breadnut seed flours range from 4.94%(fermented breadnut seed flour) to 5.42%(roasted breadnut seed flour). Fatty acid profile showed that breadnut seed flours contain a greater amount of non-essential fatty acids which were highly significant (p < 0.05) in oleic acid (57.93%) for roasted breadnut seed flour followed by linoleic acid (25.76%) in fermented breadnut flour. Stearic acid was the only prominent non-essential fatty acid in the breadnut seed flour and ranged from 4.40%(fermented breadnut seed flour) to 6.27%(germinated breadnut seed flour). The study revealed that all the processed breadnut seed flours have appreciable quantities of dietary fibre and essential fatty acids than non-essential fatty acids. Breadnut seed should be recommended in wheat substitution in bakery industry and culinary uses. It is also recommended for weight loss program.
文摘Last Sunday,I felt very hungry when I got up late.There was no food in the fridge,so l decided to cook noodles for me①.First,I filled the pot with water and put it on the stove.I waited patiently for the water to boil.Then,I put the noodles into the boiling water.Next,I added some vegetables,an egg,and a little salt.
基金supported by the National Natural Science Foundation of China(Project No.52166004)the National Key Research and Development Program of China(Project No.2022YFC3902000)+2 种基金the Major Science and Technology Special Project of Yunnan Province(Project Nos.202202AG050007202202AG050002)the Research on the Development of Complete Sets of Technology for Extraction of Aromatic Substances from Tobacco Waste and Its Application,Applied Research-Pyrolysis Process Technology Research(2023QT01).
文摘In modern engineering,enhancing boiling heat transfer efficiency is crucial for optimizing energy use and several industrial processes involving different types of materials.This study explores the enhancement of pool boiling heat transfer potentially induced by combining perforated copper particles on a heated surface with a sodium dodecyl sulfate(SDS)surfactant in saturated deionized water.Experiments were conducted at standard atmospheric pressure,with heat flux ranging from 20 to 100 kW/m2.The heating surface,positioned below the layer of freely moving copper beads,allowed the particle layer to shift due to liquid convection and steam nucleation.The study reports on the influence of copper bead diameter(2,3,4,and 5 mm),particle quantity,arrangement,and SDS concentration(20,200,and 500 ppm).It is shown that the combination of 5 mm particles and a 500 ppm SDS concentration can yield a remarkable 139%improvement in heat transfer efficiency.As demonstrated by direct flow visualization,bubble formation occurs primarily in the gaps between the particles and the heated surface,with the presence of SDS reducing bubble size and accelerating bubble detachment.
基金supported by the National Natural Science Foundation of China(Grant No.52306026)the State Key Laboratory of Air-Conditioning Equipment and System Energy Conservation Open Project(Project No.ACSKL2021KT01)The APC was covered by the Special Innovation Project Fund of the the State Key Laboratory of Air-Conditioning Equipment and System Energy Conservation Open Project(Project No.ACSKL2021KT01).
文摘This study investigates the flow boiling heat transfer coefficient and pressure gradient of refrigerant R410A inmicro-channel flat tubes.Experiments were conducted at saturation temperatures ranging from 25℃ to 30℃,mass fluxes between 198 and 305 kg/m^(2)s,and heat fluxes from 9.77 to 20.18 kW/m^(2),yielding 99 sets of local heat transfer coefficient data.The results show that increasing heat flux and mass flux enhances the heat transfer coefficient,although the rate of enhancement decreases with increasing vapor quality.Conversely,higher saturation temperatures slightly reduce the heat transfer coefficient.Additionally,the experimental findings reveal discrepancies in the accuracy of existing pressure drop and heat transfer coefficient prediction models under the studied conditions.This study recommends using the Kimand Mudawar correlation to predict pressure gradients within the tested range,with aMean Error(ME)of−5.24%observed in this study.For heat transfer coefficients,the Cooper and Kandlikar correlations are recommended,achieving a Mean Absolute Error(MAE)of approximately 22%.This research provides value for performance prediction and parameter selection of micro-channel technology in broader application scenarios within heating,ventilation and air-conditioning fields.
基金supported by the Beijing Municipal Science&Technology Commission(Z231100006123010).
文摘In this study,the flow boiling characteristics of R1234yf in parallel microchannels were experimentally investigated.The experiments were conducted with heat flux from 0 to 550 kW/m^(2),mass flux of 434,727,and 1015 kg/(m2 s),saturation temperatures of 293,298,and 303 K,and inlet sub-cooling of 5,10,and 15 K.The analysis of the experimental results provides the following conclusions:a reduced mass flux and lower subcooling correspond to a diminished degree of superheat at the boiling inception wall;conversely,an elevated saturation temperature results in a reduced amount of superheat at the boiling inception wall.Furthermore,an increase in sub-cooling and saturation temperature will enhance heat transfer efficiency.The wall temperature is mostly influenced by variations in saturation temperature and is minimally related to changes in mass flux and subcooling degree.An increase in mass flux results in a greater pressure drop attributed to heightened frictional pressure loss.The variation in pressure drop with respect to sub-cooling is minimal,while an increased saturation temperature correlates with a reduced pressure drop due to the formation of smaller bubbles and lowered frictional pressure loss at high saturation pressures.This study thoroughly examines and summarizes the effects of mass flow rate,saturation temperature,and subcooling on the flow-boiling heat transfer and pressure drop characteristics of R1234yf.Furthermore,the new correlation has 93.42%of the predicted values fall within a 15%mean absolute error,exhibiting a mean absolute error of 5.75%.It provides a superior method for predicting the flow-boiling heat transfer coefficients of R1234yf in the heat sink of parallel microchannels compared to existing correlations.
基金supported by the National Natural Science Foundation of China(Project No.52166004)the National Key Research and Development Program of China(Project No.2022YFC3902000)the Major Science and Technology Special Project of Yunnan Province(Project Nos.202202AG050007,202202AG050002).
文摘This research explores the characteristics of boiling in inclined pipes,a domain of great importance in engineering.Employing an experimental visualization technique,the boiling dynamics of deionizedwater are examined at varying inclination angles,paying special attention to the emerging flow patterns.The findings demonstrate that the inclination angle significantly impacts flow pattern transitions within the 0°to 90°range.As the heat flux rises,bubbles form in the liquid.The liquid’s inertia extends the bubble-wall contact time,thereby delaying the onset of bulk bubble flow.Beyond a 90°inclination,however,the patterning behavior is more influenced by the fluid velocity.At low speeds,incomplete pipe filling results in a large liquid plug hindering flow,while high speeds lead to full pipe filling.In general,gravity,inertia,buoyancy forces,and capillary forces are themain influential factors in the considered problem.However,an analysis of the heat transfer coefficient and boiling curve for different inclination angles reveals that the observed variations are essentially due to corresponding changes in the flow pattern.Finally,an optimal mass flux and inclination angle,able to minimize total entropy generation and improve heat transfer efficiency,are determined by means of an entropy generation analysis.
基金funded by the National Natural Science Foundation of China(Grant No.52276047)the Open Fund of NationalKey Laboratory of SpacecraftThermal Control(Grant No.NKLST-JJ-202401011)the Beijing Municipal Science&Technology Commission(Grant No.Z231100006123010).
文摘Flow boiling in open microchannels offers highly efficient heat transfer performance and has attracted increasing attention in the fields of heat transfer and thermalmanagement of electronic devices in recent years.However,the continuous rise in power density of electronic components imposesmore stringent requirements on the heat transfer capability of microchannel flow boiling.HFE-7100,a dielectric coolant with favorable thermophysical properties,has become a focal point of research for enhancing flow boiling performance in open microchannels.The flow boiling heat transfer performance ofHFE-7100 was investigated in this study by fabricating micro-nano composite structures on the bottom surface of open microchannels using laser ablation technology.Based on visualization results,a comparative analysis was conducted on the bubble dynamics and flow pattern characteristics of HFE-7100 flow boiling in micronano structured open microchannels(MNSOMC)and smooth-surface open microchannels(SSOMC),to elucidate the enhancement mechanism of micro-nano structures on flow boiling heat transfer in open microchannels.The results indicate that the surface structures and strong wettability of MNSOMC accelerated bubble nucleation and departure.Moreover,bubbles in the channel tended to coalesce along the flow direction,forming elongated slug bubbles with high aspect ratios,which enabled efficient thin film evaporation in conjunction with intense nucleate boiling,thereby significantly enhancing flow boiling heat transfer.Under the experimental conditions of this study,the maximum enhancements in the heat transfer coefficient(HTC)and critical heat flux(CHF)of HFE-7100 inMNSOMC were 33.4%and 133.1%,respectively,with the CHF reaching up to 1542.3 kW⋅m^(−2).Furthermore,due to the superior wettability and capillary wicking capability of the micro-nano composite structures,the significant enhancement in flow boiling heat transfer was achieved without incurring a noticeable pressure drop penalty.
文摘The evaporation ofmicrometer and millimeter liquid drops,involving a liquid-to-vapor phase transition accompanied by mass and energy transfer through the liquid-vapor interface,is encountered in many natural and industrial processes as well as in numerous engineering applications.Therefore,understanding and predicting the dynamics of evaporating flows have become of primary importance.Recent efforts have been addressed using the method of Smoothed Particle Hydrodynamics(SPH),which has proven to be very efficient in correctly handling the intrinsic complexity introduced by the multiscale nature of the evaporation process.This paper aims to provide an overview of published work on SPH-based simulations related to the evaporation of drops suspended in static and convective environments and impacting on heated solid surfaces.After a brief theoretical account of the main ingredients necessary for the modeling of drop evaporation,the fundamental aspects of SPH are revisited along with the various existing formulations that have been implemented to address the challenges imposed by the physics of evaporating flows.In the following sections,the paper summarizes the results of SPH-based simulations of drop evaporation and ends with a few comments on the limitations of the current state-of-the-art SPHsimulations and future lines of research.
文摘Ingredients: 125 grams of chicken breast meat, 125 grams of pork tenderloin, edible fungus, tremella, winter bamboo shoots and cucumbers, 100 grams of edible oil, 100 grams of corn starch and an optional amount of soy sauce, cooking wine, vinegar, salt and MSG, soup stock, eggs, water soaked from Chinese prickly ashes, soya bean paste, scallions, ginger roots and garlic to taste. Directions: 1. Slice the chicken breast meat, the pork tenderloin, bamboo shoots and cucumbers. Add the chicken meat, egg whites and corn starch. Marinate the tenderloin in the Chinese prickly
文摘This is a story of a young man named Owen, who lived in a faraway country, and a king, who was getting old and needed to find a successor(1). The king had thought of a way to find a successor who would have courage and be honest.
基金the National Natural Science Foundation of China(No.52006140)。
文摘The increasingly stringent emission regulations and fuel consumption requirements have elevated the demands of internal combustion engines with higher fuel efficiency and lower emissions.It has been widely demonstrated that fash boiling spray can generate shorter and wider spray with improved atomization and evaporation to promote a better air-fuel mixing process.In this study,macroscopic(far-field)spray morphologies and primary breakup(near-field)characteristics of a two-hole gasoline direct injection injector are investigated under non-flash boiling and flash boiling conditions.High speed macroscopic and microscopic imaging was used to capture the overall spray structure and near-field characteristics,respectively.N-Hexane is used as the test fuel with the injection pressure ranging from 10 MPa up to 40 MPa.For sub-cooled liquid fuel sprays,increasing fuel pressure contributes to enhanced fuel atomization and evaporation.Evident collapses occurred under fare flash boiling conditions,and higher injection pressure weakened this phenomenon since the spray cone angle decreased due to a higher injection velocity.
基金financially supported by the project of the China Geological Survey(DD20230292,DD20242591)。
文摘The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the Yanshanian.Isotope compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou complex.Ore-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage II-3.These systematic changes are closely related to the processes of mineral precipitation and fluid evolution.Sulfide precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur fugacity.Condensation of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native tellurium.Based on these hypotheses,this paper present a polyphase metallogenic model as follow.During the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early ores.During the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit.
基金supported by the Ministry of Science and High Education of Russia(Theme No.121031700169-1).
文摘The regime of horizontal subcooled film boiling is characterized by the formation of a thin layer of vapor coveringthe surface of a flat horizontal heater. Based on the equations of motion of a viscous incompressible fluid and theequation of heat transfer, the stability of such a vapor film is investigated. The influence of the modulation of thegravity field caused by vertical vibrations of the heater of finite frequency, as well as a constant electric fieldapplied normal to the surface of the heater, is taken into account. It is shown that in the case of a thick vaporfilm, the phase transition has a little effect on the thresholds for the occurrence of parametric instability in thesystem and its transformation into the most dangerous one. At the same time, the electric field contributes toan increase in these thresholds. It was found that the effect of vibrations on the stabilization of non-parametricinstability in the system is possible only in a narrow region of the parameter space where long-wave damped disturbances exist and consists of reducing the critical heat flux of stabilization. A vapor film stabilized in this waycan be destroyed due to the development of parametric instability. In contrast to the case of a thick vapor layer,the threshold for the onset of parametric instability for thin films largely depends on the value of subcooling in thesystem. In addition, this threshold decreases with increasing electric field strength. For a vapor film ten micronsthick, the instability threshold can be reduced by a factor of three or more by applying an electric field of aboutthree million volts per meter.
基金supported by the National Natural Science Foundation of China(Project Nos.12272270,11972261).
文摘Flash boiling atomization(FBA)is a promising approach for enhancing spray atomization,which can generate a fine and more evenly distributed spray by increasing the fuel injection temperature or reducing the ambient pressure.However,when the outlet speed of the nozzle exceeds 400 m/s,investigating high-speed flash boiling atomization(HFBA)becomes quite challenging.This difficulty arises fromthe involvement ofmany complex physical processes and the requirement for a very fine mesh in numerical simulations.In this study,an HFBA model for gasoline direct injection(GDI)is established.This model incorporates primary and secondary atomization,as well as vaporization and boilingmodels,to describe the development process of the flash boiling spray.Compared to lowspeed FBA,these physical processes significantly impact HFBA.In this model,the Eulerian description is utilized for modeling the gas,and the Lagrangian description is applied to model the droplets,which effectively captures the movement of the droplets and avoids excessive mesh in the Eulerian coordinates.Under various conditions,numerical solutions of the Sauter mean diameter(SMD)for GDI show good agreement with experimental data,validating the proposed model’s performance.Simulations based on this HFBA model investigate the influences of fuel injection temperature and ambient pressure on the atomization process.Numerical analyses of the velocity field,temperature field,vapor mass fraction distribution,particle size distribution,and spray penetration length under different superheat degrees reveal that high injection temperature or low ambient pressure significantly affects the formation of small and dispersed droplet distribution.This effect is conducive to the refinement of spray particles and enhances atomization.
基金supported by theResearch Starting Programof Ludong University(Grant No.221/20220045).
文摘In this paper,a new approach called the Eulerian species method was proposed for simulating the convective and/or boiling heat transfer of nanofluids.The movement of nanoparticles in nanofluids is tracked by the species transport equation,and the boiling process of nanofluids is computed by the Eulerian multiphase method coupled with the RPI boiling model.The validity of the species transport equation for simulating nanoparticles movement was verified by conducting a simulation of nanofluids convective heat transfer.Simulation results of boiling heat transfer of nanofluids were obtained by using the commercial CFD software ANSYS Fluent and compared with experimental data and results from another numerical method(Eulerian three-phase model).Good agreement with experimental data was achieved,and it was proved the Eulerian species method is better than the Eulerian three-phase model since it can give better simulation results with higher accuracy but needs fewer computation resources.
基金The work was carried out under the state contract of IT SB RAS(No.121031800216-1)supported by the joint funding of RFBR(No.20-58-46008,Anton Surtaev)TUBITAK(No.119N401,Ali Kosar).
文摘To date,using biphilic surfaces is one of the most promising methods for enhancing heat transfer and critical heat flux during boiling simultaneously.However,most of studies on the effect of biphilic surfaces on boiling perfor-mance have been carried out under atmospheric pressure conditions.In this context,the issues of heat transfer enhancement and stabilization of the boiling process at subatmospheric pressures are particularly critical due to the interesting characteristics of boiling heat transfer and bubble dynamics at subatmospheric pressures and their practical significance including aerospace applications.This paper investigates the effect of the pitch size between hydrophobic spots on a biphilic surface on heat transfer and bubble dynamics during boiling at subatmospheric pressures(from 11.2 kPa up to atmospheric pressure).The data analysis using infrared thermography demonstrated that the maximum heat transfer rate was achieved on a surface with a uniform pitch size(6 mm)at all pressures.In this case,the heat transfer enhancement,compared a bare surface,reached 3.4 times.An analysis of the departure diameters of bubbles based on high-speed visualization indicated that the optimal configuration of the biphilic surface corresponds to the pitch size equal to the bubble departure diameter.Using high-speed visualization also demonstrated that an early transition to film boiling was evident for configurations with a very high density of hydrophobic spots(pitch size of 2 mm).
基金supported by theResearch Starting Programof Ludong University(Gran No.221/20220045).
文摘Boiling heat transfer,as an efficient heat transfer approach,that can absorb a large amount of latent heat during the vaporization,is especially suitable for heat transfer occasions with high heat flux demands.Experimental studies show that the surface tension coefficient of pure water can be reduced sharply(up to 25%)when it is magnetized by amagnetic field applied externally.In this paper,magnetized water(MW)was used as the work fluid to conduct boiling heat transfer experiments,to explore the influence of magnetization on the boiling characteristics of pure water.The electromagnetic device was used to magnetize water,and then the MW was used as the work-fluid of boiling heat transfer experiments,the bubble dynamic behavior of the MW boiling was captured by a video camera,and the characteristics andmechanism were analyzed.It was found that at the same conditions,the boiling of MW can produce more vapor bubbles of smaller size than the water without magnetization,which leads to a higher heat-transfer efficiency.This indicates that magnetization can enhance the boiling heat transfer of pure water.Furthermore,the thermal conditions required by magnetized water when the boiling is started are lower than the non-magnetized water boiling,whichmeans the earlier start of nucleate pool boiling when using the MW.
