Wet Bed Research Articles

Two-layer multi-state SPH modelling of momentum growth and its feedback in viscous debris flow on wet bed sediment

Two-layer multi-state SPH modelling of momentum growth and its feedback in viscous debris flow on wet bed sediment

Prevalence and Distribution of Rice Root Knot Nematode in Rice Nurseries in Chitwan and Lamjung Districts of Nepal

To determine the natural infection of the rice root-knot nematode (Meloidogyne graminicola Golden & Brichfield) in rice nurseries, a survey was carried out in Chitwan and Lamjung in June and July of 2022. Rice nurseries were randomly selected based on geographical location, agro-ecological region, land type, cropping practice, and soil type. Forty rice nurseries were surveyed i.e. twenty from each district and 100 seedlings from each nursery as the sample for the study using the simple random method of sampling were evaluated. Field survey revealed that M. graminicola was widely distributed in most rice growing areas of Chitwan and Lamjung districts. Most of the rice nurseries in Lamjung district were found to be infested with M. graminicola as compared to that of the Chitwan district. Disease severity was reported up to 23.26% in Lamjung and 20.2% in Chitwan district. Additionally, the study showed that dry bed conditions were more likely to be affected by rice root-knot disease than wet bed conditions. The majority of farmers planted seedlings on upland (dry) soil, where second-stage juvenile (J2) populations and rice root-knot disease were more common. Most farmers (87.5%) have limited knowledge about rice root knot nematodes and their control methods. This suggested a significant loss in rice output and a high danger of nematode multiplication. This information will provide knowledge about the prevalence of nematode and enabling rice growers in this region to design and implement an appropriate control strategy for managing M. graminicola.

Experimental study on wavefront flow characteristics of dam-break wave at initial stage on wet bed

The flow characteristics of dam-break wave in the initial stage of downstream wet bed are studied experimentally by digital image measurement technologies. First, the fine wavefront structure and its velocity were captured by the optical flow method, and an image measurement technology of water level based on edge detection was proposed. Then, the comparison and verification were carried out using the numerical simulation. The mean error is −7.369%, −1.243%, and 1.317% under depth ratio (σ) is 0.2, 0.25, and 0.33, and the error of most cases is within ±15% except σ = 0.2. The results show that large eddy simulation combined with volume of fluid method could accurately predict the distribution of dam-break water level, but it tends to overestimate the propagation velocity of the wavefront by about 10.3%. In addition, Stoker's quasi-steady paradigm has been proven to accurately predict the mean and steady-state flow characteristics of dam-break wave. Furthermore, the wavefront structure of the initial stage was subdivided into three sub-stages, namely, the jump stage, the transition stage, and the stable stage. Following that, the flow characteristics of each stage under the condition of the σ = 0.25 were studied in detail. The results show that the morphology of the wavefront structure is driven by the transformation of its internal energy in the initial stage. In summary, the work reveals the flow characteristics and quantitative flow results of the initial stage of dam-break wave under the wet river bed, thus improving the accuracy of dam-break accident prediction.

Experimental study on the influence of water depth and bed slope variations on dam-break flood wave propagation

Damage to dam structures frequently results in catastrophic consequences. Consequently, understanding of the characteristics of the movement of dam-break flow along the sloping wet bed can assist in the issuance of timely flood warnings and risk mitigation. In this study, a series of large-scale flume experiments was conducted with the objective of investigating the effects of upstream and downstream water depth and bed slope on the propagation of dam-break waves. The water level is measured and processed to calculate the wavefront velocity. Results show that the wave propagation behavior can be classified as bore and undular waves through the global Froude numbers (Frx) and local Froude numbers (Frl). When Frx < 1.225 or Frl < 1.475, the dam-break wave propagates as the undular wave. In the undular wave state, the wavefront velocity (U) decreases with increasing water depth ratio α. Additionally, the U with Frx shows a similar trend, where the experimental value surpasses the analytical solution. The dimensionless maximum wave height (ΔHmax) increases with Frx and then decreases. The deviation from the analytical solution ranges between 67.22% and 127.38%. When Frx > 1.225 or Frl > 1.475, the dam-break wave propagates as the bore wave. In the bore wave state, the U increases slightly with the water depth ratio α, while the change rule of U with Frx is similar to it. The dimensionless maximum wave height (ΔHmax) remains relatively constant as Frx increases, showing a high degree of consistency with the analytical solution. The presence of bed slope results in increased wavefront velocity and wave heights, while an increase in α results in the emergence of more pronounced undular wave phenomena. Furthermore, the experimental results are compared with existing analytical solutions, and the validity of the analytical solutions and their limitations are discussed.

Management of the refractory nocturnal enuresis patient to desmopressin in a pediatric population: Desmopressin + oxybutynin vs. desmopressin + imipramine

Desmopressin is well accepted as first-line medical therapy for enuresis. If ineffective, combination therapy of desmopressin+oxybutynin or desmopressin+imipramine has been used. This study assessed the efficacy of adjunct therapy with either imipramine or oxybutynin in the management of enuresis patients who failed desmopressin treatment. A retrospective chart review of our database for patients with enuresis was performed. Patients who were prescribed desmopressin, oxybutynin, and imipramine over 14 years for enuresis were included. Two cohorts of patients were examined; group OXY was treated with desmopressin and oxybutynin, and group IMP received desmopressin and imipramine. Pretreatment measurement of Vancouver Symptom Scores (VSS) were used to compare groups using the VSS question "I wet my bed at night" where 4: every night, 3: 4-5 nights per week, 2: 1-2 nights per week, 1: 3-4 nights per month, and 0: never. International Children's Continence Society (ICCS) criteria for continence success was utilized to determine outcomes. 2521 patients prescribed one of the 3 medications were identified. Among them, 81 patients (mean age: 10.5±2.8 years) received combination therapy. Of which, 55 were male and 26 female. Specifically, 58 were prescribed both desmopressin and imipramine (group IMP), 23 desmopressin and oxybutynin (group OXY), and 4 transitioned from OXY to IMP. Mean pretreatment VSS showed no difference between groups. Both groups experienced minimal drops in wet nights with desmopressin alone. A comparison revealed that group IMP reduced wet nights significantly more than group OXY (VSS wet night score 0.7±1.2 vs. 2.3±1.1 respectively, p<0.0001). Non-intent-to-treat complete response rate was 68% vs 5% (OR=42.5, p<0.001) (IMP vs. OXY respectively). Intent-to-treat response rates were 58%. Although first-line desmopressin treatment for enuresis is effective, it does not work for all patients, and many parents and children desire nighttime dryness. Clinicians have combined desmopressin with oxybutynin or imipramine for improved results, but research comparing these modalities is scarce. Our study suggests that the desmopressin and imipramine combination is superior at reducing nights wet compared to desmopressin and oxybutynin, attributed to imipramine's probable central mechanism rather than its secondary anticholinergic properties. Limitations include a modest sample size, retrospective design, and subjective responses to the Vancouver questionnaire. A combination of desmopressin and imipramine was more effective in reducing wet nights and had a complete response rate that was 42.5 times greater than desmopressin and oxybutynin.

Numerical simulations of dam-break flows of viscoplastic fluids via shallow water equations

This paper presents simulations of dam-break flows of Herschel–Bulkley viscoplastic fluids over complex topographies using the shallow water equations (SWE). In particular, this study aims to assess the effects of rheological parameters: power-law index (n), consistency index (K), and yield stress (τc\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ au _{c}$$\\end{document}), on flow height and velocity over different topographies. Three practical examples of dam-break flow cases are considered: a dam-break on an inclined flat surface, a dam-break over a non-flat topography, and a dam-break over a wet bed (downstream containing an initial fluid level). The effects of bed slope and depth ratios (the ratio between upstream and downstream fluid levels) on flow behaviour are also analyzed. The numerical results are compared with experimental data from the literature and are found to be in good agreement. Results show that for both dry and wet bed conditions, the fluid front position, peak height, and mean velocity decrease when any of the three rheological parameters are increased. However, based on a parametric sensitivity analysis, the power-law index appears to be the dominant factor in dictating fluid behaviour. Moreover, by increasing the bed slope and/or depth ratio, the wave-frontal position moves further downstream. Furthermore, the presence of an obstacle is observed to cause the formation of an upsurge that moves in the upstream direction, which increases by increasing any of the three rheological parameters. This study is useful for an in-depth understanding of the effects of rheology on catastrophic gravity-driven flows of non-Newtonian fluids (like lava or mud flows) for risk assessment and mitigation.Graphical abstract

Experimental investigations of propagation characteristics and wave energy of dam-break waves on wet bed

Understanding the characteristics of dam-break flows that move along a sloping wet bed is essential for timely flood warnings and risk mitigation. This study conducts laboratory experiments in a sizable flume, encompassing various upstream and downstream water depths and bed slopes. It examines the effects of the ratio between upstream and downstream water depths and the slope of the flume on the dam-break wave height and the velocity of the wavefront. The findings revealed that the average relative error between theoretical and experimental values initially decreases and increases as the slope rises. The dam-break waveform is characterized by introducing a global Froude number Frx and a local Froude number Frl, with critical values of Frx=1.225 and Frl=1.475. In addition, a model for predicting the dam-break wave height is developed by linearly fitting the values between dimensionless wave height and the local Froude number, and it is validated by comparison to experimental data. Based on experimental data and the Stoker equation, an attenuation function for the dam-break wave height at a downstream location is proposed for the undular wave. Finally, a theoretical analysis is conducted to predict the energy of the first dam-break wave.

H2O2/acid self-supplying double-layer electrospun nanofibers based on ZnO2 and Fe3O4 nanoparticles for efficient catalytic therapy of wound infection.

Catalytic therapy based on nanozymes is promising for the treatment of bacterial infections. However, its therapeutic efficacy is usually restricted by the limited amount of hydrogen peroxide and the weak acidic environment in infected tissues. To solve these issues, we prepared polyvinyl alcohol (PVA)-polyacrylic acid (PAA)-iron oxide (Fe3O4)/polyvinyl alcohol (PVA)-zinc peroxide (ZnO2) double-layer electrospun nanofibers (PPF/PZ NFs). In this design, PVA serves as the carrier for ZnO2 nanoparticles (NPs), Fe3O4 NPs, and PAA. The double-layer structure of nanofibers can spatially separate the PAA and ZnO2 to avoid their reaction with each other during preparation and storage, while in the wet wound bed, PVA can dissolve and PAA can provide H+ ions to promote the generation of hydrogen peroxide and subsequent conversion to hydroxyl radicals for bacteria killing. In vitro experimental results demonstrated that PPF/PZ NFs can reduce the methicillin-resistant Staphylococcus aureus by 3.1 log (99.92%). Moreover, PPF/PZ NFs can efficiently treat the bacterial infection in a mouse wound model and promote wound healing with negligible toxicity to animals, indicating their potential use as "plug-and-play" antibacterial wound dressings. This work provides a novel strategy for the construction of double-layer electrospun nanofibers as catalytic wound dressings with hydrogen peroxide/acid self-supplying properties for the efficient treatment of bacterial infections.

Drop impact on wet granular beds: effects of water-content on cratering.

Drop impact events on a wet granular bed show a rich variety by changing the substrate composition. We observe the drop impact onto dry/wet granular substrates with different grain sizes (50-400 μm) and water contents (0-22 vol%). Despite the fixed impactor conditions (impact velocity: 4.0 m s-1, water drop radius: 1.8 mm), the experiment reveals that the post-impact behaviors of both the impactor and target are strongly influenced by the substrate composition. We categorize these behaviors into several phases concerning liquid splashing and crater shapes left after the event. As these phases are relevant to each other, we measure the mechanical characteristics of the substrates and find that the onset of splashing and particle ejection is explained via the fracture of the substrate. Furthermore, we discuss several timescales of the event to understand the phase separations in more detail. Consequently, we find that the splashing phase and the crater shape are determined by competition among the timescales of impact, penetration, and contact.

Varietal Evaluation of Promising Spring Rice Genotypes in Bagdula, Pyuthan, Nepal

A field experiment was carried out in order to assess the performance (growth, yield, and yield-attributing characteristics) of five different spring rice genotypes. The study was conducted in a farmer’s field in Bagdula, Pyuthan, under the supervision of Prime Minister Agriculture Modernization Project (PMAMP), Rice Zone, Pyuthan, from March 2021–July 2021. Five spring rice genotypes, including PR-126, HHZ 25-DT9-Y1-Y1, IR 103575-76-1-1-B, IR 99742:2-11-17-1-9-B, and IR 86515-19-1-2-1-1-1-1, were evaluated in a randomized complete block design (RCBD) with four replications each. Plant growth and yield-attributing parameters were measured, entered into MS-Excel, and analyzed using the R-Studio software. Rice seedlings were raised in a wet nursery bed and transplanted at a spacing of 20 cm x 20 cm (3 seedlings per hill). The highest plant height (82.25 cm) and number of tillers per hill (10.40) were recorded in IR 86515-19-1-2-1-1-1-1, whereas the lowest plant height was observed in genotype IR 99742:2-11-17-1-9-B (64.30 cm). The highest number of effective tillers per square meter (247.125), panicle length (24.43 cm), number of grains per panicle (206.35), thousand grain weight (25.90 g), and grain yield (6.630 t.ha-1) were recorded in PR-126, whereas the highest straw yield was recorded in IR 86515-19-1-2-1-1-1-1 (5.78 t.ha-1). Similarly, the lowest numbers of effective tillers per square meter (150.73), panicle length (18.51 cm), number of grains per panicle (158.30), and thousand grain weight (22.53 g) were recorded in IR 99742:2-11-17-1-9-B. Thus, based on the yield and other growth parameters, the PR-126 genotype was found to be the most suitable for achieving greater productivity in Bagdula, Pyuthan, Nepal. However, further multilocation yield trials, including assessments of nutrient content, should be conducted for validation.

A Finite Volume Method for a 2D Dam-Break Simulation on a Wet Bed Using a Modified HLLC Scheme

This study proposes a numerical model for depth-averaged Reynolds equations (shallow-water equations) to investigate a dam-break problem, based upon a two-dimensional (2D) second-order upwind cell-centre finite volume method. The transportation terms were modelled using a modified approximate HLLC Riemann solver with the first-order accuracy. The proposed 2D model was assessed and validated through experimental data and analytical solutions for several dam-break cases on a wet and dry bed. The results showed that the error values of the model are lower than those of existing numerical methods at different points. Our findings also revealed that the dimensionless error parameters decrease as the wave propagates downstream. In general, the new model can model the dam-break problem and captures the shock wave superbly.

Carbon dioxide desorption behavior of potassium carbonate supported on gamma-alumina solid sorbent in wet fluidized bed under steam atmosphere

Since the carbon dioxide (CO2) capture using solid sorbent is a reversible reaction, the solid sorbent can be regenerated by the desorption process. Therefore, the desorption process is one of the key important processes for the CO2 capture system. Traditionally, most of the literature studies focus on the desorption of solid sorbent under an N2 atmosphere. However, the desorption process of the solid sorbent is inappropriate in the real system because the system will need another process to separate CO2 and nitrogen (N2) after the desorption process. This study focused on the CO2 desorption of potassium carbonate supported on gamma-alumina (K2CO3/γ-Al2O3) in a wet fluidized bed under a steam atmosphere by using the multiphase computational fluid dynamics (CFD) simulation. The effects of water thickness and dry restitution coefficient on CO2 desorption rate were investigated to provide a realistic particle collision behavior and to explore their effects on CO2 desorption phenomena. Moreover, the effect of steam velocity on the hydrodynamic behaviors of fluidization which on CO2 desorption rate was studied. The simulated results demonstrated that all the parameters, water thickness, dry restitution coefficient, and steam velocity had significantly affected system hydrodynamics and CO2 desorption rate in the wet fluidization desorption process. Furthermore, the effect of desorption temperature on CO2 desorption rate was evaluated for finding the appropriate temperature for CO2 desorption process of K2CO3/γ-Al2O3. The results showed that the appropriate desorption temperature for CO2 desorption under steam atmosphere was the temperature over 150 °C.

MPS-based simulation of dam-break wave propagation over wet beds with a sediment layer

In this study, a two-phase mesh-free method is employed to simulate the dam-break wave propagation along different wet bed conditions in the presence of sediment. The method is based on the mixture theory and volume fraction is incorporated for both water and sediments. The pressure Poisson equation is explicitly solved to obtain the pressure field for the water and the pressure field for the sediment is calculated by using the rheology model. The method is validated by simulating submerged granular column collapse and dam-break flow over a sediment layer. The method can reproduce the interface variation between water and sediment. The validated model is then used to simulate the dam-break wave propagation in the presence of both downstream water and sediment. Different dam-break waves induced by the upstream water depths are simulated and it is found that the dam-break wave can make the sediment move violently. The larger downstream water depth can slow down the sediment movements while the sediment movements are violent for shallower water downstream.

Numerical simulation of transient pipe flow with entrapped air and wet bed effects

In this study, the evolution of transient pipe flow along the wet bed is numerically investigated. In the investigation, the shear stress transport k-ω model is used and the volume of fluid method is employed to track the surface of air and water. Two key parameters in the flow as upstream head H and initial water depth h in the pipe are examined. It is found that the bottom stress is significantly affected by the two parameters. The upstream head H determines the magnitude of the shear force, and the downstream water depth in the pipe affects the stability of the shear force. The boundary layer separation and flow pattern are the essential causes of shear instability. By analyzing the simulation results, an empirical equation with the average flow velocity is obtained to estimate the overflow capacity of the pipe by just the upstream water level and the depth of the wet bed.

MP70-01 MANAGEMENT OF THE REFRACTORY NOCTURNAL ENURESIS PATIENT TO DESMOPRESSIN IN A PEDIATRIC POPULATION: DESMOPRESSIN + OXYBUTYNIN VS. DESMOPRESSIN + IMIPRAMINE

You have accessJournal of UrologyCME1 Apr 2023MP70-01 MANAGEMENT OF THE REFRACTORY NOCTURNAL ENURESIS PATIENT TO DESMOPRESSIN IN A PEDIATRIC POPULATION: DESMOPRESSIN + OXYBUTYNIN VS. DESMOPRESSIN + IMIPRAMINE Spencer Shain, Jordan Gitlin, Amelia Pantazis, Ronnie Fine, Mark Horowitz, Steven Friedman, Paul Zelkovic, Lori Dyer, Richard Schlussel, Jamie Freyle, Alexander Fang, Jessica Sommer, and Israel Franco Spencer ShainSpencer Shain More articles by this author , Jordan GitlinJordan Gitlin More articles by this author , Amelia PantazisAmelia Pantazis More articles by this author , Ronnie FineRonnie Fine More articles by this author , Mark HorowitzMark Horowitz More articles by this author , Steven FriedmanSteven Friedman More articles by this author , Paul ZelkovicPaul Zelkovic More articles by this author , Lori DyerLori Dyer More articles by this author , Richard SchlusselRichard Schlussel More articles by this author , Jamie FreyleJamie Freyle More articles by this author , Alexander FangAlexander Fang More articles by this author , Jessica SommerJessica Sommer More articles by this author , and Israel FrancoIsrael Franco More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003338.01AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Desmopressin (DDAVP) is well accepted as first-line medical therapy for nocturnal enuresis (NE). If DDAVP is ineffective, combination therapy of DDAVP+oxybutynin (Oxy) or DDAVP+imipramine (Imp) has been used. This study assessed the efficacy of adjunct therapy with either Imp or Oxy in the management of NE patients who failed DDAVP treatment. METHODS: A retrospective chart review of our database for patients with NE was performed. All patients who were prescribed DDAVP, Oxy, and Imp over 14 years for NE were included. Two cohorts of patients were examined; group A was treated with DDAVP and Oxy, and group B was treated with DDAVP and Imp. Pretreatment measurement of Vancouver Symptom Score (VSS) was used to compare groups as well as the VSS question “I wet my bed at night” with 4: I wet my bed every night, 3: 4-5 nights per week, 2: 1-2 nights per week, 1: 3-4 nights per month, and 0: never. ICCS criteria for continence success was utilized to determine outcomes. Statistical analysis was performed with SPSS. RESULTS: 2521 patients were identified who were prescribed one of the 3 medications. 72 patients with a mean age of 9.8±2.8 years were identified, of which 48 were male and 24 female. Of these patients, 58 were prescribed both DDAVP and Imp (group B), 23 DDAVP and Oxy (group A), and 9 transitioned from group A to group B. Mean pretreatment VSS showed no difference between the groups. Both groups had minimal drops in wet nights with DDAVP alone. When comparing groups, it was found that group B reduced wet nights significantly more than group A (VSS wet night score 0.7 vs 2.3 respectively). Complete response rate was 68% vs 5% (OR=42.5, p<0.001) (Imp vs Oxy respectively). CONCLUSIONS: A combination of DDAVP and Imp was more effective in reducing wet nights and had a complete response rate that was 42.5 times greater than DDAVP and oxybutynin. Source of Funding: None. © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e1003 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Spencer Shain More articles by this author Jordan Gitlin More articles by this author Amelia Pantazis More articles by this author Ronnie Fine More articles by this author Mark Horowitz More articles by this author Steven Friedman More articles by this author Paul Zelkovic More articles by this author Lori Dyer More articles by this author Richard Schlussel More articles by this author Jamie Freyle More articles by this author Alexander Fang More articles by this author Jessica Sommer More articles by this author Israel Franco More articles by this author Expand All Advertisement PDF downloadLoading ...

Which rice farming system is more environmentally friendly in Khuzestan province, Iran? A study based on emergy analysis

This research was conducted with the aim of (i) evaluating the sustainability of three rice production systems (DBS: dry bed seeding, TP: transplanting, and WBS: wet bed seeding) in Khuzestan province, Iran, (ii) introducing the most cost-effective and sustainable system, and (iii) providing solutions to increase the systems' sustainability and efficiency. In order to analyze the studied systems during the 2020–2021 growing season, several emergy-based and economic indicators were analyzed. The total emergy inputs supporting the systems are estimated to be 2.69E+16, 4.16E+16, and 3.17E+16 sej ha−1 yr−1 for DBS, TP, and WBS, respectively. The three studied farming systems were determined to be inefficient and unsustainable due to their reliance on purchased resources including labor, fossil fuel, and seed/transplant. According to the environmental loading ratio and modified environmental loading ratio indicators, the WBS and TP systems exerted less pressure on ecosystems and were more sustainable than the DBS system due to the greater quantity of purchased renewable flows (labor and seed/transplant). The results of the emergy renewability, emergy sustainability index, and modified emergy sustainability index indices indicated that the three investigated systems were not sustainable, indicating that high energy consumption in rice farming systems resulted in a significant environmental burden. The economic analysis of rice production systems revealed that the DBS system was economically superior due to its lower total production costs, especially labor costs, when compared with the other two systems. In light of the water scarcity crisis in Iran, the DBS method is recommended due mainly because of its ability to save 30–60% of irrigation water in the studied areas compared with the other two systems that have high water consumption. Due to the lower sustainability and greater environmental pressure of the DBS method compared with the two studied farming systems, it is also recommended to decrease the proportion of nonrenewable inputs (fossil fuel, chemical fertilizers, and herbicides) and increase the proportion of renewable inputs (organic fertilizer).

Basal Melt Patterns around the Deep Ice Core Drilling Site in the Dome A Region from Ice-Penetrating Radar Measurements

Basal melt in the Dome A region will influence the deep-ice-core drilling at Kunlun Station. The melting point (wet bedrock) has a higher reflectivity than the surrounding area, which can be assessed using radar echoes from the bedrock. This paper uses a linear absorption model to determine wet and dry ice–bedrock interfaces around the Kunlun drilling site. In the determination process, an artificial intelligence model was applied to extract the ice–bedrock interface for inferring the ice thickness. Additionally, the various depth-averaged attenuation rates were used to identify the maximal range of basal melting. We mapped the patterns of the wet points on the bottom of the ice sheet and the modeled basal temperature to verify the results of the wet bed conditions. According to these maps of wet bed conditions, the areas with basal melting around the drilling site primarily appear in valley walls with low basal temperatures and are linked with hydraulic potential and bedrock elevation. Identifying the ice–bedrock interface is challenging in the valley bottom area, where the melting points are less than at the valley walls. Additionally, the melting proportions of 11.8% and 3.62% were calculated from two ice-penetrating radar data in this research. The mapped melting points around the site of Kunlun ice core drilling suggest complex ice flow effects and can be used to better interpret archives of old ice for paleoclimate research.

Kinetics models of hydrogen sulphide adsorption from hydrogel biochar derived from empty fruit bunch (EFB)

This research aims to investigate the detailed state of adsorption kinetics modelling and research on the application of hydrogen sulfide adsorption by hydrogel derived from empty fruit bunch (EFB), the determination of the kinetics parameters, and the comparison between models in a selection of the best-fit model.The kinetics modelling used are pseudo-first-order and pseudo-second-order models. The correlation coefficient was used to evaluate the suitability of the equation R2. After obtaining the results, the comparison was made by comparing the R2 of each model. The pseudo-second-order model has a higher value of correlation coefficient, R2, making it the most suitable kinetics model for adsorption systems.The R2 for pseudo-first-order on the effect of dry bed height was 0.8814, whereas its effect on powder bed height was 0.9537, and that of the wet bed height was 0.9607. Meanwhile, the R2 for pseudo-second-order on the effect of dry bed height was 0.89, on the effect of the powder bed height was 0.99, and on the effect of the bed height of wet was 0.99, the highest among kinetic models. Based on the results, the pseudo-second-order model best describes the adsorption of hydrogen sulfide (H2S) by hydrogel biochar.The kinetics modelling used are pseudo-first-order, and pseudo-second-order models for hydrogen sulfide adsorption by hydrogel originating from empty fruit bunches (EFB).Based on the results, the pseudo-second-order model best describes the adsorption of hydrogen sulfide (H2S) by hydrogel biochar. Kinetic studies are important in understanding the reactions and design of the process.The authenticity results of this article were found to be 17% similar. The novelty of this paper is the kinetics study of the new adsorbent developed based on EFB to adsorb H2S.

Review of CFD-DEM Modeling of Wet Fluidized Bed Granulation and Coating Processes

Wet fluidized bed granulation and coating processes have been widely used in the pharmaceutical and food industries. The complex gas–solid flow coupled with heat and mass transfer in such processes made it hard to form complete control over the apparatuses. To serve better design, scaling-up, and optimization of granulators and coaters, the underlying micro-scale mechanisms must be clarified. Computational fluid dynamics coupled with the discrete element method (CFD-DEM) provides a useful tool to study in-depth the gas-solid hydrodynamics of the granulation and coating processes. This review firstly introduced the fundamental theory of CFD-DEM from governing equations, force calculation, and coupling schemes. Then the application of CFD-DEM in simulating wet fluidized bed granulation and coating was presented. Specifically, the research focus and the role of CFD-DEM in resolving issues were discussed. Finally, the outlook on the development of CFD-DEM in the context of granulation and coating was given.

STATUS AND PROSPECTS OF SPRING RICE IN NEPAL: A REVIEW

Spring rice as an alternative to the main season rice has been under major priority of Nepal Government for its huge potential in self-reliance in grain food production and food security in Nepal. Though having higher production and productivity, it was found that its production area had not been scaled up as anticipated. Sowing time is adjusted considering cold stress and pre-monsoon rainfall. Seedlings are generally raised in wet bed and dry bed nurseries based on availability of spring water and 30-40 days seedlings are transplanted in the Nepali month of Chaitra (Mar/Apr). Water being crucial during the growth stages of rice plant, water level of 2-5 cm is found to have better yield and performance. Whereas mainly 16 elements including both micro and macro elements have been required for proper growth and development of rice which were mainly supplied through FYM, compost, urea and DAP. Various cultural, mechanical and chemical methods are found for management of weeds. Similarly, IPM approach as well as modern approaches like gene manipulation, resistant varietal development have been evolving instead of solely pesticides application for better protection of spring rice crop in the present context.