Wet Treatment Research Articles

Enhancement of device performance in β-Ga2O3 Schottky barrier diodes with tetramethylammonium hydroxide treatment

Schottky barrier diodes were fabricated on tetramethylammonium hydroxide (TMAH)-treated β-Ga2O3 surfaces with Ni/Au as Schottky metal contacts. TMAH wet surface treatment efficiently reduced the roughness of the β-Ga2O3 surface. An X-ray photoelectron emission analysis of the TMAH-treated β-Ga2O3 surface chemical binding features indicates the effective removal of unwanted surface oxides and contaminants formed unintentionally by chemisorption during exposure to ambient conditions. The TMAH-treated Au/Ni/β-Ga2O3 Schottky diode displayed improved rectification behavior with an increment of barrier height by 0.30 eV compared to the untreated diode. The breakdown voltages (Vbr) for the untreated and TMAH-treated Au/Ni/β-Ga2O3 Schottky barrier diode are 298 and 358 V, respectively. The decrease in the turn-on resistance (Ron) in the Au/Ni/β-Ga2O3 Schottky barrier diode by TMAH treatment can be ascribed to the improved surface morphology. The improved electrical behavior of the Au/Ni/β-Ga2O3 Schottky barrier diode formed on the TMAH-treated β-Ga2O3 surface can be accredited to the oxygen vacancies reduction, that deceased the carrier concentration in the β-Ga2O3 epilayer and to the improved the surface morphology. These results demonstrate the effectiveness of TMAH wet surface treatment on β-Ga2O3 and its potential as a simple method for fabricating β-Ga2O3-based devices with improved performance.

Effect of interfacial treatments on wet joints performance in steel-UHTCC composite bridge decks

Using Ultra-High Toughness Cementitious Composite (UHTCC) to the wet joints of composite bridge decks (CBDs) is a new solution to the cracking issue under hogging moments. Interfacial treatments and reinforcement details play a critical role in enhancing the crack resistance performance of wet joints in CBDs, while the quantitative impact of these factors on wet joints utilizing UHTCC materials remains uncertain. In this study, three different wet joint interfacial treatments (surface roughening, smearing epoxy adhesive, applying both) were proposed and the crack resistance performance were investigated through hogging moment tests on CBDs. During the tests, failure modes, flexural capacity, deformation behavior, force mechanism, crack propagation process and strain development of the CBD specimens with different wet joint details were discussed. To investigate the crack resistance performance of different wet joint interfaces, theoretical model for calculating nominal UHTCC tensile stress considering steel/UHTCC interfacial slip was constructed. Subsequently, the development curves of maximum crack width with nominal UHTCC tensile stress at wet joint interfaces were plotted. Test results indicated that interfacial treatment methods exert a distinct influence on the crack resistance performance of wet joints in steel-UHTCC CBDs. For reinforcement-enhanced wet joints, wet joint interfaces can be treated only with surface roughening, and the crack resistance performance was comparable to that treated with the combination of surface roughening and epoxy adhesive. Wet joint interfaces treated with the combination of surface roughening and epoxy adhesive exhibit a smaller value and growth rate of maximum crack width compared to those treated only with epoxy adhesive, and the cracking stresses σ0.05, σ0.1, and σ0.2 at wet joint interfaces were improved by 41.1%, 35.7%, and 232.6%, respectively. The wet joint interfaces in conventional wet joints are recommended to be treated with a combination of surface roughening and epoxy adhesive, resulting in smaller growth rates of interfacial maximum crack width. Moreover, the cracking stresses σ0.1 and σ0.2 at these interfaces were respectively improved by 577.4% and 400% compared to those treated only with surface roughening.

Mechanistic insights into the adaptive evolvability of spore heat resistance in Bacillus cereus sensu lato

Wet heat treatment is a commonly applied method in the food and medical industries for the inactivation of microorganisms, and bacterial spores in particular. While many studies have delved into the mechanisms underlying wet heat killing and spore resistance, little attention has so far been dedicated to the capacity of spore-forming bacteria to tune their resistance through adaptive evolution. Nevertheless, a recent study from our group revealed that a psychrotrophic strain of the Bacillus cereus sensu lato group (i.e. Bacillus weihenstephanensis LMG 18989) could readily and reproducibly evolve to acquire enhanced spore wet heat resistance without compromising its vegetative cell growth ability at low temperatures. In the current study, we demonstrate that another B. cereus strain (i.e. the mesophilic B. cereus sensu stricto ATCC 14579) can acquire significantly increased spore wet heat resistance as well, and we subjected both the previously and currently obtained mutants to whole genome sequencing. This revealed that five out of six mutants were affected in genes encoding regulators of the spore coat and exosporium pathway (i.e. spoIVFB, sigK and gerE), with three of them being affected in gerE. A synthetically constructed ATCC 14579 ΔgerE mutant likewise yielded spores with increased wet heat resistance, and incurred a compromised spore coat and exosporium. Further investigation revealed significantly increased spore DPA levels and core dehydration as the likely causes for the observed enhanced spore wet heat resistance. Interestingly, deletion of gerE in Bacillus subtilis 168 did not impose increased spore wet heat resistance, underscoring potentially different adaptive evolutionary paths in B. cereus and B. subtilis.

MicroRNA expression profiling in tears and blood as predictive biomarkers for anti-VEGF treatment response in wet age-related macular degeneration.

This study aimed to investigate the potential of microRNAs (miRNAs) in tears, blood, and aqueous humor as biomarkers for predicting treatment response in wet age-related macular degeneration (AMD) patients undergoing anti-vascular endothelial growth factor (anti-VEGF) therapy. In a single-center prospective cohort study, treatment-naïve wet AMD patients and age-matched controls were enrolled. Clinical data and miRNA levels (miR-199a-3p, miR-365-3p, miR-200b-3p, miR-195-5p, miR-335-5p, and miR-185-5p) in tears, blood, and aqueous humor were collected. Treatment response was categorized into responders and non-responders based on visual acuity and central subfield thickness. MiRNA levels were quantified using reverse-transcription PCR. Statistical analyses were performed, including ROC analysis, to evaluate predictive accuracy. Dysregulated miRNA profiles were observed in wet AMD tears and blood compared to controls. Specifically, miR-199a-3p, miR-195-5p, and miR-185-5p were upregulated, while miR-200b-3p was downregulated in tears. All six miRNAs were elevated in wet AMD blood samples. Notably, responders showed higher tear expression of miR-195-5p and miR-185-5p. Combining these miRNAs yielded the highest predictive power (AUC = 0.878, p = 0.006) for anti-VEGF responders. Dysregulated miRNA profiles in tears and blood suggest their potential as biomarkers for wet AMD. MiR-195-5p and miR-185-5p in tears demonstrate predictive value for anti-VEGF treatment responders. This study underscores the non-invasive prediction potential of miRNA tear analysis in wet AMD treatment responses.

"Simmer pus and grow flesh" method promotes chronic wound healing in rats via bFGF-Wnt β-catenin signaling pathway.

The purpose of this study was to explore the mechanism of "simmer pus and grow meat" method based on bFGF regulating WNT / β-Catenin signaling pathway. Of 100 SPF rats, 25 were randomly selected as blank group, and 75 rats were established chronic infectious wound model and divided into blank group, model group (normal saline treatment, n = 25), experimental group (purple and white ointment treatment, n = 25), and wet burn ointment group (wet burn treatment, n = 25). The wound healing rate of rats was compared. The protein expressions of PCAN, VEGF, bFGF, β-Catenin, GSK-3β and C-Myc in granulation tissues were detected. On the 7th day, the wound healing rate of the model group was lower than that of the other 3 groups (P<0.05), and the wound healing rate of the positive control group was higher than that of the experimental group and the control group (P<0.05). The expressions of bFGF, GSK-3β and C-MyC in model group were higher than those in control group (P<0.05). The β-catenin protein expression in the model group was lower than that in the control group (P<0.05), and the β-catenin protein expression in the experimental group and the positive control group was higher than that in the model group (P<0.05). The expressions of PCAN and VEGF in model group were lower than those in model group (P<0.05). We found that Zibai ointment promotes chronic wound healing by modulating the bFGF/Wnt/β-Catenin signaling pathway.

A non‐antibiotic organic coating on ZA6‐1 surface releasing different concentrations of sodium dodecyl sulphate/levulinic acid for orthopaedic application

AbstractBone implantation surgery is often accompanied by bacterial infection, resulting in infectious bone non‐union, pathological fracture and other serious consequences, which will aggravate the pain of patients. A non‐antibiotic coating consisting of sodium dodecyl sulphate (SDS) and levulinic acid (LA) with different concentrations was prepared by the authors on the zinc–aluminium alloy (ZA6‐1) using a wet chemistry treatment for orthopaedic application. The influence of SDS/LA concentrations on the surface morphology, composition and performance of the developed coating was investigated. The results showed that as‐prepared coating on a zinc alloy surface could improve the substrate's corrosion resistance and increase the degradation rate from 0.82 to 19.70 μm/year upon raising the SDS/LA concentration. Furthermore, higher hydrophilicity (&lt;14°), better cell proliferation (&gt;100%) and morphology, as well as good cell adhesion and differentiation (ALP &gt;95% for 7 days) were observed on coated zinc alloys. The increased SDS/LA concentration slightly weakens the biocompatibility and enhances the antibacterial performance of coated zinc alloys due to the synergistic effect of SDS/LA. Overall, the coating comprising 6 wt.% SDS and 9 wt.% LA showed excellent antibacterial action with a high level of biocompatibility, confirming its potential application for orthopaedic implants.

Effect of atmospheric plasma treatment and wet blast on adhesion characteristics of carbon fiber reinforced LM-PAEK thermoplastic composites

Surface characteristics of polymeric materials are quite challenging for adhesion especially thermoplastics, requiring specific surface preparation operations before reaching successful bonding. These processes are principally aimed to increase the low surface energy of the material, bonding agent contact area and wetting characteristics to provide proper and strong adhesion. In this study, two different surface treatments with different processing parameters were applied to CF/LM-PAEK thermoplastic composites in order to examine the changes on surface characteristics and adhesion strengths. Apart from desired surface treatments for thermoplastics indicated in previous studies and backgrounds, wet blasting method is used to prepare surfaces before bonding. Separately prepared surfaces, applying wet blasting and atmospheric plasma treatment, were adhered using epoxy-based film adhesive to be subjected to single lap shear testing to examine adhesion strength under tensile loading. According to the results of experimental study, it was observed that both surface treatments increased the adhesion strength of the bonded pre-consolidated CF/LM-PAEK thermoplastic composites compared to specimens having untreated surfaces.Atmospheric plasma treatment increased the surface energy by 18.24% and showed higher strength up to 14.93% compared to the untreated specimens. On the other hand, surprisingly, wet blasted specimens with lower surface energies showed high strength up to 6.48% compared to the untreated specimens. In addition to surface energies and lap shear strengths, roughness measurements and SEM surface evaluations were also issued to enlighten obtained test results accordingly.

Phenotypic lags influence rapid evolution throughout a drought cycle.

Climate anomalies are increasing and posing strong selection, which can lead to rapid evolution. This is occurring on a backdrop of interannual variability that might weaken or even reverse selection. However, the effect of interannual climatic variability on rapid evolution is rarely considered. We study the climatic differences that contribute to rapid evolution throughout a 7-year period, encompassing a severe drought across 12 populations of Mimulus cardinalis (scarlet monkeyflower). Plants were grown in a common greenhouse environment under wet and dry treatments, where specific leaf area and date of flowering were measured. We examine the association between trait values and different climate metrics at different time periods, including the collection year, prior years, and cumulative metrics across sequential years. Of the climatic variables we assessed, we find that anomalies in mean annual precipitation best describe trait differences over our study period. Past climates, of 1-2 years prior, are often related to trait values in a conflicting direction to collection-year climate. Uncovering these complex climatic impacts on evolution is critical to better predict and interpret the impacts of climate change.

Over 43%-power-efficiency GaInN-based photoelectric transducer on free-standing GaN substrate for optical wireless power transmission system

We investigated the GaInN-based photoelectric transducers (PTs) aiming at the application to optical wireless power transmission systems. A PT device structure with Ga0.9In0.1N multiple-quantum-wells (MQWs) as a light absorption layer was grown on a free-standing GaN substrate by metalorganic chemical vapor deposition and subjected to the device fabrication. The PT performance was evaluated via the two-terminal current-density vs. voltage characteristics taken under a monochromatic light illumination. The fabricated PT devices exhibited a high open-circuit voltage of approximately 2.3 V and a high shunt resistance of 41 kΩcm2, thanks to its good material qualities. In addition, its surface reflection was markedly suppressed by an adoption of a wet surface treatment and an anti-reflection coating, resulting in a high external quantum efficiency of 90% and a high short-circuit current density of 1.4 mAcm−2. Through the above investigation, a high power-conversion efficiency as great as 43.7% was achieved for the GaInN MQW PTs at a light illumination with 390 nm in wavelength and 5 mWcm−2 in optical power density.

Efficacy of wet cupping in the pain management of cervical spondylosis – A randomized, controlled, open -label, parallel-group clinical trial

Background and objectiveCervical spondylosis is a chronic degenerative process of the cervical spine characterized by pain in neck, degenerative changes in intervertebral disc and osteophyte formation. Cervical spondylosis is translated as Wajaʻ ur Raqaba, a type of joint pain. The present study was aimed to evaluate the effect of wet cupping in the pain management of cervical spondylosis. MethodsThis Open, randomized, controlled, clinical study was conducted on 44 patients. Subjects in the test group (n = 22) received a series of three-staged wet cupping treatment, performed on 0, 7th and 14th day. Subjects in the control group (n = 22) received 12 sittings of Transcutaneous Electrical Nerve Stimulation (TENS): 6 sittings per week for two weeks. The objective findings of treatment were assessed with the help of VAS, Neck Disability Index (NDI) and Cervical range of motion. ResultsIntra group comparison in test group from baseline to 21st day were found highly significant (p < 0.001) in terms of VAS, NDI, Flexion, Extension and Left rotation score. While in Right rotation, Left rotation and Left lateral flexion score were found moderately significant (p < 0.01). Statistically significant difference was observed between two groups at 21st day in VAS scale, NDI, and Cervical range of motion score (p < 0.001). Interpretation and conclusionḤijāma Bish Sharṭ was found better in the management of pain due to cervical spondylosis than TENS. It can be concluded that Ḥijāma Bish Sharṭ may a better option for the pain management of cervical spondylosis. Clinical trial registrationThe trial was registered on clinical trial registry website (www.ctri.nic.in) bearing a CTRI Number, CTRI/2020/03/024,249.

Cover crops and irrigation impacts on corn production and economic returns

Increases in irrigated crop acreage and frequent droughts during the growing season have caused continual groundwater decline of the Mississippi River Valley Alluvial Aquifer in the Mississippi Delta region. A field experiment was conducted from 2019 to 2021 to determine if combinations of irrigation scheduling thresholds and cover crops (CCs) could improve corn (Zea mays L.) production, water productivity (WP), irrigation water use efficiency (IWUE), and net returns. The irrigation thresholds used for irrigation scheduling were a wet threshold (−40 kPa), a dry threshold (−90 kPa), and no irrigation. The CC treatments were cereal rye (Secale cereale L.), hairy vetch (Vicia villosa R.), wheat (Triticum aestivum L.)-radish (Raphanus sativus L.)-turnip (Brassica rapa L.) mix, and no cover crop. In 2020, CCs reduced corn yield by 9–26% compared to no cover crop. In 2021, wet irrigation threshold treatments had 8% and 9% higher corn yield than no irrigation and dry irrigation threshold treatments, respectively. No irrigation treatments showed higher WP than dry and wet irrigation thresholds, while hairy vetch had higher in WP among CC treatments in year two of this study. Hairy vetch under the dry irrigation threshold had higher IWUE than all other treatments. The no-CC treatments generated $167, $340, and $58 ha−1 more under the wet, dry, and no irrigation treatments, respectively, when averaged over both years. Water conservation was affected by CC selection and irrigation management.

Innovative ionic liquid pretreatment followed by wet disk milling treatment provides enhanced properties of sugar palm nano-fibrillated cellulose

In order to accommodate the increased demand for innovative materials, intensive research has focused on natural resources. In pursuit of advanced substances that exhibit functionality, sustainability, recyclability, and cost-effectiveness, the present work attempted an alternative study on cellulose nanofibers derived from sugar palm fiber. Leveraging an innovative approach involving ionic liquid (IL) pre-treatment, bleaching, and wet disc mill technique, nano-fibrillated cellulose (NFC) was successfully obtained from the sugar palm fiber source. Remarkably, 96.89% of nanofibers were extracted from the sugar palm fiber, demonstrating the process's efficacy and scalability. Further investigation revealed that the sugar palm nano-fibrillated cellulose (SPNFC) exhibited a surface area of 3.46 m2/g, indicating a significant interface for enhanced functionality. Additionally, the analysis unveiled an average pore size of 4.47 nm, affirming its suitability for various applications that necessitate precise filtration. Moreover, the surface charge densities of SPNFC were found to be −32.1 mV, offering opportunities for surface modification and enhanced interactions with various materials. The SPNFC exhibit remarkable thermal stability, enduring temperatures of up to 360.5 °C. Additionally, the isolation process is evident in a significant rise in the crystallinity index, escalating from 50.97% in raw fibers to 61.62% in SPNFC. These findings shed light on the vast potential and distinct features of SPNFC, opening the path for its application in a wide array of industries, including but not limited to advanced materials, biomedicine, and environmental engineering.

Feasibility of Non-Remanufactured Waste Bottle Glass as Supplementary Cementitious Material

Theoretically, glass can be recycled entirely, but there are several requirements for remanufacturing. For the first time, this work studied industrial bottle waste glass (WG), which cannot be used to remanufacture new glass as a cement replacement for concrete applications. Wet and dry milling treatments were performed to reduce the particle size of WG and remove fibre and plastic contaminants. The different waste glasses treated were characterised by chemical, physical, and morphological analysis. Afterwards, mortar-level studies followed, using raw WG and wet-milled WG (AGWG) as a 10% Portland cement replacement. Mechanical and several durability indicators were assessed. WG and AGWG incorporation improved mortar performance against water capillary absorption, chloride ingress, and alkali–silica reaction. The unfavourable effect, namely, mechanical strength loss on glass-modified mortars, was mainly due to fibre contaminants observed by SEM on WG and AGWG samples. Even though wet milling reduced the amount and length of the fibre contaminants, it still did not guarantee adequate mechanical strength for the mortar. Thus, additional or alternative treatments, such as thermal treatments, must be explored.

Screening support effect of Pt/MOx for selective hydrogenation of cinnamaldehyde

In supported metal catalysts, solid support material is of great importance for immobilizing and dispersing metal species, which can affect the catalytic performance of supported metal catalysts in terms of selectivity. Rational design of supported metal catalysts with tailored performance, in particular with controlled catalytic performance, is highly desired yet poses challenges in chemoselective hydrogenation reactions. Here, platinum nanoparticles (Pt NPs) supported on a series of commercial oxides were synthesized by a facile wet impregnation and thermal treatment under the air. The catalytic performance of as-prepared catalysts was evaluated in chemoselective hydrogenation of cinnamaldehyde. The varied product distribution demonstrates that supports affect markedly on selectivity. Fourier transform infrared spectra (FTIR) spectroscopy reveals that the high selectivity towards cinnamyl alcohol could be attributed to the preferential adsorption of aldehyde group. Meanwhile, the existence of Ptδ+ could enhance activity markedly by facilitating the spillover of activated H species.

A New Generation of Gene Therapies as the Future of Wet AMD Treatment.

Age-related macular degeneration (AMD) is an eye disease and the most common cause of vision loss in the Western World. In its advanced stage, AMD occurs in two clinically distinguished forms, dry and wet, but only wet AMD is treatable. However, the treatment based on repeated injections with vascular endothelial growth factor A (VEGFA) antagonists may at best stop the disease progression and prevent or delay vision loss but without an improvement of visual dysfunction. Moreover, it is a serious mental and financial burden for patients and may be linked with some complications. The recent first success of intravitreal gene therapy with ADVM-022, which transformed retinal cells to continuous production of aflibercept, a VEGF antagonist, after a single injection, has opened a revolutionary perspective in wet AMD treatment. Promising results obtained so far in other ongoing clinical trials support this perspective. In this narrative/hypothesis review, we present basic information on wet AMD pathogenesis and treatment, the concept of gene therapy in retinal diseases, update evidence on completed and ongoing clinical trials with gene therapy for wet AMD, and perspectives on the progress to the clinic of "one and done" therapy for wet AMD to replace a lifetime of injections. Gene editing targeting the VEGFA gene is also presented as another gene therapy strategy to improve wet AMD management.

Well-established carbon nanomaterials: modification, characterization and dispersion in different solvents

Three different types of carbon nanomaterials, SWCNTs, MWCNTs and GNPs were prepared, modified, characterized, and their dispersibility behavior in three different solvents was evaluated. The carbon nanotubes were synthesized by using the well-known chemical vapor deposition method and the graphene nanoplatelets by wet physicochemical treatment techniques. Their characterization was accomplished by using various advanced techniques, such as powder X-ray diffraction and Raman spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and N2 adsorption at 77 K. Furthermore, the carbon nanostructures were modified via plasma treatment and wet chemical surface modification in order to enhance their dispersion characteristics, for achieving more homogenous suspensions and therefore to be remained dispersed over a reasonable period of time without any sedimentation. The effect of treatment parameters and the use of different solvents were thoroughly studied mainly by optical methods, but also by using the DIN/EN classified ISO method of oil absorption and UV–Vis spectroscopy. The enhanced dispersion rate is observed in both CNTs and GNPs materials following their surface treatment, especially when using the solvent n-methyl-2-pyrrolidone. The aforementioned studied nanomaterials are perfect candidate fillers for preparing polymeric mixed matrix membranes.Graphical abstract

Upcycling MSWI fly ash into green binders via flue gas-enhanced wet carbonation

Municipal solid waste incineration (MSWI) fly ash is a type of hazardous waste generated from waste incineration plants. This study developed a novel approach that recycled MSWI fly ash into eco-friendly binders via flue gas-enhanced wet carbonation treatment. During various washing processes, potentially toxic elements (PTEs) in MSWI fly ash showed different leaching patterns and pH dependence. Results suggested that 30 min flue gas-enhanced washing (optimal pH = ∼10.5) was favourable for immobilization of PTEs as well as sequestration of CO2 (12 wt %). The 28-day compressive strength of the pastes with 30 wt % flue gas-washed MSWI fly ash reached 84.2 MPa, which was significantly higher than the control pastes. Most of the PTEs, chlorides were effectively stabilised and solidified in the matrix. Compared to the cement-based binder, the cost of an alternative binder with 30 wt % flue gas-washed MSWI fly ash was −229.6 USD/m3, and the carbon emissions could be reduced by 36.1 %. Therefore, recycling carbonated MSWI fly ash into green binders exhibits a huge potential to close the waste cycle and mitigate climate change.

Evaluating wet and dry contact time of contaminated produce with chlorine solution against Listeria monocytogenes and Salmonella enterica

Chlorine is the most widely used sanitizer, however, there are varying reports on the exposure time and its effectiveness on fresh produce. This study determined the minimum exposure time for wet and dry contact chlorine treatments with the highest efficacy in reducing Listeria monocytogenes and Salmonella enterica on spinach and bell pepper surfaces. The chlorine wash at 100 mg/L for 1 min resulted in a significant reduction (p < 0.05) of both pathogens on both produce. S. enterica was reduced by 4.86 log CFU/g on spinach and by 3.97 log CFU/g on bell pepper, while L. monocytogenes was reduced by 3.7 log CFU/g on spinach and by 3.08 log CFU/g on bell pepper. The majority of Listeria cross-contamination (>2.30 log CFU/g) on un-inoculated spinach and bell peppers was observed within 1 min of chlorine washing. Cross-contamination of Salmonella on spinach was >2.9 log CFU/g within 1 min and the level increased to 4.21 log CFU/g after 6 min. This study showed that washing spinach and bell pepper for up to 6 min with a 100 mg/L chlorine solution did not achieve additional reductions in L. monocytogenes and S. enterica populations compared to a 1 min wash.

Faceting mechanisms of GaN nanopillar under KOH wet etching

This study presents strategies for achieving GaN pillars with the desired m- (or even a-) oriented nonpolar facets through a top-down approach that combines plasma etching followed by room temperature KOH wet treatment processes. Indeed, GaN etching in KOH solution is an anisotropic process, meaning that it allows the appearance of stable facets at the macroscopic scale, while atomic processes, such as step-flow, drive the fundamental mechanisms of the wet etching at the microscopic scale. Our study highlights the key role played by both the shape (circular or hexagonal, aligned with either the m-planes or the a-planes) and the roughness of the hard mask in determining the resulting crystalline facet formation and their associated roughness. Furthermore, it underscores the importance of the GaN pillar profiles (reentrant, straight, tapered) after plasma patterning, as they strongly influence the subsequent wet etching mechanisms. Ultimately, the article demonstrates that smooth m-oriented facets can be achieved by using room temperature wet KOH (44 wt%) on slightly sloped GaN profiles after plasma etching, in conjunction with the use of hexagonal m-oriented hard masks.

A Wetting and Drying Approach for a Mode-Nonsplit Discontinuous Galerkin Hydrodynamic Model with Application to Laizhou Bay

A wetting and drying treatment for a three-dimensional discontinuous Galerkin hydrodynamic model without mode splitting (external and internal modes) was developed. In this approach, computing elements are classified into wet, dry, and semidry elements, which are treated differently. In a Runge–Kutta time step, the reconstruction of the semidry elements and the combined utilization of two- and three-dimensional limiters help the model maintain stability. Numerical results show that the wetting and drying method can achieve a well-balanced property under the condition of still-water equilibrium and can reasonably describe the variation process of wetting and drying regions during a long wave run-up on a uniform slope and a tidal cycle in a basin with a variable slope. Analysis of the role of the limiters in the model indicated that the robustness of the three-dimensional hydrodynamic model can be effectively maintained when the two- and three-dimensional limiters are jointly applied for wetting and drying process simulation. A three-dimensional discontinuous Galerkin hydrodynamic model was applied with the presented wetting and drying method to simulate the tidal current evolution of a spring tidal cycle in southwestern Laizhou Bay in the Bohai Sea, in November 2003, and the simulated results of the water surface elevation and vertical layered current velocities agreed well with the measured data.