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Falling film flow and heat transfer are extensively encountered in various industries of renewable and sustainable energy due to the outstanding heat transfer performance. The predictions in falling film hydrodynamics and heat transfer are crucial for the optimal design of falling film heat exchangers, and there have been considerable advancements made in this area over the past few decades. Considering the gaps in current literature predictions, this paper aims to present a comprehensive review on the correlations of flow pattern transition, film thickness, heat transfer, and liquid film rupture within falling film flowing over horizontal tubes and tube bundles. Through comparisons and summarizations, it can be found that the documented correlations appear to be significantly out of alignment with one another, which greatly restricts the applicability of these predictions. The correlations of falling film thickness that are obtained using regression approach based on dimensional analysis may take into account more factors than the ones modified from Nusselt theory. The predictions of flow pattern transition of falling liquid film with horizontal column are often described as the functions of the film Reynolds number, derived from the Kapitza number or the Galileo number. The functions of Nusselt number, film Reynolds number, Prandtl number, and Archimedes number are typically used to represent sensible and evaporative heat transfer correlations, whereas boiling heat transfer correlations also take into account the influence of heat flux, such as Boiling number. The full process of actual heat transfer is taken into account from both the standpoints of sensible convection and nucleate boiling using the combination functions of various heat transfer forms. Within the ranges of their own parameters, the well-established heat transfer models often offer good accuracy. While the predictions of phase change heat transfer often behave worse, the predictions of sensible heat transfer are more general and accurate. Generally speaking, the minimum film flow rate or the maximum heat flux were the functions that correlated with the inceptions of liquid film rupture. • Provides a comprehensive review of predictions for falling film hydrodynamics and heat transfer. • Describes in fully the most recent advancements in the relevant correlations. • Reviews respectively heat transfer prediction of sensible convection, evaporation, and boiling. • Provides an entire review of falling film heat transfer from subcooled convection to film dryout. • Proposed some recommendations and improvements for future research. [ABSTRACT FROM AUTHOR]

• Numerical study on falling film flow and heat transfer on porous tubes. • Compared falling film flow and heat transfer on plain and porous tubes. • Studied porosity, layer thickness, and material effects on flow and heat transfer. • Porous layer leads lower flow, thinner film, fewer rupture, better heat transfer. • Smaller porosity, thicker layer, aluminum and copper facilitate heat transfer. Porous surfaces often exhibit exceptional performance in liquid spreading and heat transfer, making them promising candidates for enhancing falling film heat transfer on solid surfaces. This paper delves into the flow and heat transfer characteristics occurring within falling films on horizontal tubes coated with a porous layer. To achieve this, a three-dimensional numerical model that couples the Volume of Fluid (VOF) method with porous media considerations was employed. The investigation comprehensively covers film spreading behavior, flow patterns, film velocity, film thickness, temperature distribution, and heat transfer coefficients, for both plain and porous tubes. Furthermore, we delve into the effects of key parameters, such as porosity, layer thickness, and material properties, on the overall heat transfer process. The results demonstrate the accuracy of our model in reproducing film thickness and heat transfer coefficients within falling films on horizontal porous tubes. When comparing plain tubes to porous ones, some key differences emerge. Specifically, the liquid film on porous tubes spreads more slowly, leading to increased film thickness and fewer occurrences of dry patches. Additionally, porous tubes result in lower film velocity and a more uniform temperature field compared to plain tubes. Interestingly, the findings reveal that smaller porosities yield thicker films and higher heat transfer coefficients, particularly when the porosity is below 0.4. Moreover, thicker porous layers result in thinner films, higher wetting ratios, and increased heat transfer coefficients. Among the materials we tested, aluminum and copper porous layers exhibit the highest heat transfer performance, while steel demonstrates the lowest. [ABSTRACT FROM AUTHOR]

• Thoroughly studied the variables affecting falling film dehumidification on corrugated plates. • Provided the optimum shape of the corrugated plate for falling film dehumidification performance. • Proposed a mass transfer correlation based on the current numerical data. • Clarified the enhancement mechanism of the corrugated surface for falling film dehumidification. Due to a number of benefits, liquid desiccant dehumidification has received a lot of attention lately. In comparison to previous improvement strategies, corrugated plates have demonstrated higher efficacy in liquid desiccant dehumidification. This study employs computational fluid dynamics to examine the dehumidification performance of falling film liquid desiccant dehumidification on over sinusoidally shaped corrugated plates. The effects of plate geometries, solution parameters, and moist air (concentration of humidity, temperature, and flow rate) were discussed. Additionally, a mass transfer correlation was proposed based on the current numerical data. It is indicated that the corrugated plate significantly enhances dehumidification performance due to the liquid film waves intensification, mass transfer area expansion, and induction of vortexes close to the gas-liquid interface. The most effective falling film dehumidification is achieved using a corrugated plate with a wavelength of 5.0 mm and an amplitude of 0.5 mm. By raising the solution or air inlet temperature, the dehumidification rate is reduced while being strengthened by raising the solution or air inlet concentration, velocity, or air humidity. While decreasing when solution intake concentration or air velocity rises, the efficacy of dehumidification rises as solution velocity does. The proposed mass transfer correlation accurately predicts 93.3 % of the 45 data, with an error of 11 % or less. In the current parameter scopes, the magnitude has a more significant effect on Sh air than the wavelength. Adjustments to air velocity and solution concentration can cause significant fluctuations in Sh air , while air and solution temperature have little effect on Sh air. [ABSTRACT FROM AUTHOR]

This study classifies the evolutionary properties of coal char pore structure which occur during coal gasification. CO 2 gasification of various coal samples was carried out in a fixed bed reactor. The resulting chars were analysed using N 2 isothermal adsorption/desorption and scanning electron microscopy (SEM), coupled with fractal theory. Analytical results indicate that the pore structure of coal char underwent micropore evolving, enlarging and overlapping, while more mesopores and macropores developed with continued gasification. The surface area of coal char increased to its maximum value when carbon conversion reached approximately 50%. Fractal calculation results showed that two types of fractal structures associated with the coal char surface and pore structure underwent stereome development and elapsing. However, the evolutionary properties were unique for different coal samples. High rank coal had a complex spatial structure with more micro-pores, whereas lower rank coal had a much flatter spatial structure. • The evolution of char pore structure during coal gasification were investigated. • Micropore underwent evolving, enlarging and overlapping, formed mesopores/macropores. • Micropore evolution was well described by using two new type fractal dimensions. • The micropore of low rank coal char evolved relatively slowly with gasification. [ABSTRACT FROM AUTHOR]

• Tested cross vapor effect on the falling film evaporation of low pressure refrigerant. • Conducted larger vapor velocity effect on falling film evaporation in tube bundle. • Compared the cross vapor effect on falling film evaporation of R123 and R134a. • Visualized the cross vapor effect on falling liquid film flow and heat transfer. The falling film evaporation and the effect of cross vapor stream in falling film evaporator with triangular tube bundle using R123 was experimentally investigated. The variations of local and bundle average heat transfer coefficients were described. The tube bundle consisted of 4 × 3 (column × row) of triangular horizontal copper tubes. The tests without vapor effect were conducted with nominal heat fluxes of 20 to 60 kWm–2, saturation temperatures of 6 to 16 °C and film flow rates of 0.016 to 0.18 kgm–1s–1. Cross vapor stream effect experiments were operated at three heat fluxes of 20, 30 and 40 kWm–2 and two film flow rates of 0.035 and 0.07 kgm−1s−1, and the vapor velocity at the narrowest interstice in the tube bundle varies from 0 to 5.0 ms−1. It is indicated that the heat transfer is seriously influenced by the bundle effect while less affected by changing of saturation temperature. With the increase in vapor velocity, the heat transfer performance is generally weakened; the cross vapor stream has a strong influence on falling film evaporation of R123. [ABSTRACT FROM AUTHOR]

A simple, practical and gram-scale process for direct transformation of primary alcohols or silyl ethers to ammonium salts was developed. This method has the feathers of easy work-up (a simple filtration), mild condition, high yield, great practicality and robustness. And the application of the ammonium salts in Suzuki coupling reaction was also accomplished. Image 1 • A simple, practical and gram-scale process for direct transformation of alcohols or silyl ethers to ammonium salts. • Easy work-up (a simple filtration), mild condition, high yield, great practicality and robustness. • Application of the ammonium salts in Suzuki coupling reaction. [ABSTRACT FROM AUTHOR]

Highlights • A simple crop model, called SIMPLE, was developed including 13 parameters to specify a crop type, with four of these for cultivar characteristics. • Commonly available inputs that are required for the SIMPLE model include daily weather data, crop management, and soil water holding parameters. • The initial SIMPLE model was calibrated for 14 different crops from 25 detailed field experiments resulting in a RRMSE of 25.4% for final yield. Abstract Crop models are important tools for assessing the impact of climate change on crop production. While multiple models have been developed over the past decades for the major food and fiber crops such as wheat, maize, soybean, rice, and cotton, there are few or none for many other crops. The goal of this study was to develop a simple generic crop model (SIMPLE) that could be easily modified for any crop to simulate development, crop growth and yield. The crop model SIMPLE includes 13 parameters to specify a crop type, with four of these for cultivar characteristics. Commonly available inputs that are required for the crop model SIMPLE include daily weather data, crop management, and soil water holding parameters. The initial SIMPLE model was calibrated and evaluated for 14 different annual crops using observations for biomass growth, solar radiation interception, and yield from 25 detailed field experiments for a total of 70 treatments from 17 sites, resulting in a RRMSE of 25.4% for final yield. A sensitivity analysis comparing a C3, C4 and a legume crop showed an expected response to a gradual increase in temperature and atmospheric CO 2 concentrations. A regional gridded simulation for US potatoes reproduced the general observed patterns of spatial yield variability. Because the model is simple, it has several limitations, including the lack of response to vernalization and photoperiod effect on phenology. The model includes water, but no nutrient dynamics. However, an advantage of the model simplicity is that it can be easily adapted and evaluated for any new crop, based on literature data and field experiments, or general crop data such as sowing and harvest dates and yield statistics. The model is available in several simulation frameworks including a stand-alone version in R, Excel and as part of DSSAT. [ABSTRACT FROM AUTHOR]

Abstract Sulfur (SVI) based moieties, especially, the sulfonyl or sulfonamide based analogues have showed a variety of pharmacological properties, and its derivatives propose a high degree of structural diversity that has established useful for the finding of new therapeutic agents. The developments of new less toxic, low cost and highly active sulfonamides containing analogues are hot research topics in medicinal chemistry. Currently, more than 150 FDA approved Sulfur (SVI)-based drugs are available in the market, and they are widely used to treat various types of diseases with therapeutic power. This comprehensive review highlights the recent developments of sulfonyl or sulfonamides based compounds in huge range of therapeutic applications such as antimicrobial, anti-inflammatory, antiviral, anticonvulsant, antitubercular, antidiabetic, antileishmanial, carbonic anhydrase, antimalarial, anticancer and other medicinal agents. We believe that, this review article is useful to inspire new ideas for structural design and developments of less toxic and powerful Sulfur (SVI) based drugs against the numerous death-causing diseases. Graphical abstract Image 1 Highlights • More than 150 sulfonamide drugs are available in the market. • Sulfonamide based drugs are huge range of therapeutic applications. • We collected 337 potent bioactive sulfonyl or sulfonamide bearing heterocyclic analogues. • We briefly explain the structure activity relationship of all molecules to develop novel drugs. [ABSTRACT FROM AUTHOR]

Highlights • A LD pumped 1347 nm laser with Nd:GdNbO4 is realized. • Theoretical simulations under 808 nm and 879 nm pumping are conducted. • Direct pumping is utilized to achieve efficient 1347 nm laser output. Abstract A diode-pumped 1347 nm laser with a novel Nd:GdNbO 4 crystal is demonstrated for the first time to our best knowledge. Laser performance around 1.3 μm under 879 nm laser diode pumping is investigated with different output mirrors, pump radii and repetition rates. A maximum average power of ∼ 373 mW at 1347 nm is achieved at 50 Hz, corresponding to an optical-to-optical efficiency of 5.5% and a slope efficiency of 6.8%. [ABSTRACT FROM AUTHOR]

The violent vibration and excessive settlement of trackbeds under high-speed train moving loads are the main problems of ballasted tracks encountered in practice, which limits the rise of operation speed for ballasted railways. To date, the possibility of extending the widely used geogrid in conventional ballasted railways to high-speed railways has not been adequately validated. The stabilization mechanism of geogrids under high-speed train moving loads remains unclear. Herein, a ballasted track DEM model containing five sleepers that reproduced high-speed train moving loads was developed through EDEM software and validated by full-scale model tests. Both cases of ballasted tracks with and without the geogrid were examined. The results showed that the geogrid significantly decreased the total and differential settlement of the ballasted track. After geogrid installation, the coordination number of ballast particles was increased, and the contact forces among ballast particles were reduced, which potentially lowered the ballast breakage. The geogrid effectively constrained the displacement and rotation of ballast particles. The reduced migration of ballast particles led to a smaller and more uniform volumetric strain field of the ballasted trackbed. By investigating the working mechanism of the geogrid, it was shown that the penetration of the ballast particles into the geogrid aperture induced the expansion of the geogrid aperture, and therefore, the lateral force from the geogrid ribs limited the movement of the ballast particles. [ABSTRACT FROM AUTHOR]

Biodegradable polymeric packaging materials are being studied for their potential to replace traditional petroleum-based ones for food contact applications. However, potential safety concerns associated with the utilization of these biodegradable polymers have not been studied in detail. In this study, we conducted non-targeted screening and migration studies on two types of biodegradable milk packaging materials, which were composed of a mixture of polylactic acid (PLA), poly(butylene adipate-co-terephthalate) (PBAT), polybutylene succinate (PBS), and cellulose. In particular, we monitored the transfer of migrating substances from the packaging materials into a food simulant (50% ethanol) and into a real food (fat free and whole milk). A screening study identified seven compounds in the biodegradable packaging bags, including degradation products of antioxidants, lubricants, and plasticizers such as triethylene glycol, diethyl succinate, glycerin, 2,4-di-tert-butylphenol, and 13-docosenamide were identified. The migration studies indicated that the types and amounts of migrating substances transferred into the real food were appreciably lower than those transferred into the food simulant. Most of the detected migrating substances were below the levels established in the European Union regulations. However, the triethylene glycol levels (68-144 mg/kg) in the food simulant exceeded the limits (60 mg/kg) for one of the packaging materials tested. A safety assessment suggested that there is a low level of safety risk associated with one of the biodegradable packaging materials. This study provides important insights into the safety of biodegradable packaging materials that might be used in the food industry. • A new method for extracting (semi)volatile compounds from milk was established. • The sources of (semi-)volatile compounds in biodegradable packaging bags are primarily processing aids. • The migration of triethylene glycol from PBAT/PBS bags exceeded the standards. • The migration of compounds from biodegradable packaging bags into 50% ethanol and milk was compared. • Migration of (semi-)volatile compounds from biodegradable bags differs significantly in 50% ethanol and milk. [ABSTRACT FROM AUTHOR]

The influence of downward vapor stream on the falling film evaporation with nucleate boiling outside a horizontal enhanced tube bundle arrayed in a vertical column is experimentally investigated. The variations in local and bundle averaged heat transfer coefficients with vapor velocity are presented. To simulate the practical condition in a falling film evaporator, the flow passages of the liquid/vapor are constructed using two quartz glass sheets and two columns of dummy half tubes. The test ranges are saturation temperature of 6 °C, film flow rate of 0.035–0.1 kgm –1 s –1 , heat flux of 20, 30, 40 kWm –2 . It is found that (1) the downward vapor effects are either positive or negative depending on the tube position, film flow rate, heat flux and vapor velocity; (2) the bundle effect becomes stronger under the effect of downward vapor stream; (3) the downward vapor has a significant effect on the heat transfer of the lower tubes than the upper tubes; and (4) the vapor stream effect on the bundle averaged heat transfer coefficient varies with the levels of film flow rate and heat flux. The experimental results provide significant guidance in the design of the vapor escape channel in a falling film evaporator. [ABSTRACT FROM AUTHOR]

The effects of film flow rate, heat flux, inlet liquid temperature, tube diameter and liquid distributor height on subcooled falling film heat transfer outside a horizontal smooth tube are numerically studied, and a heat transfer correlation based on the current data is developed. Comparisons between the predicted results and the published experimental data in the literature are also conducted. The calculation ranges are: film flow rate from 0.025 to 0.284 kg m −1  s −1 , heat flux from 1.0 to 100 kW m −2 , inlet liquid temperature from 2 to 104 °C, tube diameter from 6.35 to 50.8 mm and liquid distributor height from 3.0 to 50.8 mm. The results indicate that: (1) the numerical results of the local heat transfer coefficient are in good agreement with the experimental data in the literature; (2) the surface tension plays an important role in the calculations of heat transfer in two stagnation zones, (3) the heat transfer coefficient shows four distinct zones along with peripheral angle: stagnation zone, impingement zone, thermal layer development zone and departure zone; (4) the heat transfer coefficient increases with increase in film flow rate, tube diameter or liquid distributor height, while keeps constant with increasing heat flux; (5) the correlation predicts 92% of the total 141 calculated data with deviations within ±10%, and predicts 78% of 284 data available in literature with deviations within ±30%. [ABSTRACT FROM AUTHOR]

Objective: Cupping therapy has a long history in traditional medicine especially in Asian countries. It was controversial whether cupping induced blisters are beneficial to healing effects, and the formation and content in the blisters remain unexplored. We aimed to identify and compare the molecular components of the blister fluid from the cupping therapy and the scalds to explore the necessary of inducing cupping induced blisters.Methods: Fluid sample of blisters from fifteen patients receiving cupping therapy (Cupping group) and scald burns (Scald group) were collected in this study. Proteins from the blisters were separated by two-dimensional electrophoresis (2D-gel) and further analyzed by mass spectrometry. In addition, the changes in particular proteins were confirmed by Western blotting.Results: The protein components are significantly different between blister from cupping therapy and scalds. The immune responses, oxidative stress and metabolic related proteins (Ig lambda-2 chain C regions, Ig gamma-1 chain C region, hemopexin, prdx2, calmodulin, succinyl-CoA ligase and tetranectin) were increased, whereas the hemoglobin subunit beta was decreased in the Cupping group compared with the Scald group.Conclusions: Cupping induced blisters contain several proteins which relate to the activation of certain immune pathways including anti-oxidation, anti-apoptosis, tissue repairing and metabolic regulation. This proteomic analysis may indicate a significant clue to the mechanism study of cupping. [ABSTRACT FROM AUTHOR]

Soft soils beneath transportation infrastructures suffer dynamic traffic loads with high-frequency and high-cycle characteristics, which mainly present shakedown development of deformation yet probably induce notable deformation at the stable state. However, conventional constitutive models are still not available for the long-term behavior description of soft soils under high-cycle traffic loading. Herein, a conceptual model for high-cycle, low-amplitude undrained loading was proposed incorporating a shrinking yield surface and an expanding boundary surface, which individually indicated the weakening behavior caused by an increase in excess pore water pressure and the hardening effect due to contractive plastic deformation. Given the shakedown responses of soft soils, a mapping ratio and a one-time calculation approach were employed. Thus, the effect of loading frequency on the response of soft soil can be considered, and the calculation efficiency was greatly improved. Then, the evaluation of model parameters and parametric analyses on the loading frequency, shrinking yield surface, expanding boundary surface and mapping ratio were carried out to examine the performance of the proposed model. To further validate the proposed model, undrained cyclic triaxial tests on reconstituted Ningbo clay were conducted, and high-cycle undrained triaxial tests on Kaolin clay and Ariake clay were referenced. The predicted developments of accumulated plastic deviatoric strain and excess pore water pressure with the number of load cycles reached acceptable consistencies with the experimental results. Moreover, the effects of confining and deviatoric stresses were investigated. Not only rational developments of excess pore water pressure and plastic deviatoric strain but also nearly identical results under the same cyclic stress ratio (CSR) were obtained, which adequately confirmed the feasibility and reliability of the proposed model. Although this model was developed based on isotropically consolidated soils and contained varied parameters for different CSRs, it provides a framework contributing to rigorous model development for high-cycle conditions. [ABSTRACT FROM AUTHOR]