Expansion Of Surface Area Research Articles

Nitrogen-rich porous biochar for highly efficient adsorption of perchlorate: Influencing factors and mechanism

Nitrogen-rich porous biochar is produced by direct pyrolysis, combined with K2CO3 or ZnO activation using soybean residue as raw material, their adsorption performance and mechanism for perchlorate are investigated. The results show that the activation process significantly enhances the biochar's adsorption capacity for perchlorate, the saturated adsorption capacities of BK800 and BZ600 increase by 9 and 15 times, respectively. The adsorption process adheres to the Langmuir isotherm model and pseudo-second-order kinetic model, indicating predominant monolayer and chemical adsorption. Pore filling, hydrogen bond and electrostatic interactions play key roles in the adsorption of perchlorate on biochar. The adsorption performance of K2CO3-activated biochar improves with increasing pyrolysis temperature, attributed to the expansion of the biochar's specific surface area (BK800, 1371.7 m2 g−1). Conversely, ZnO-activated biochar exhibits high adsorption performance due to its mesoporous channels and abundant N, O-functional groups (BZ600: 1.86 % N content), despite having a lower specific surface area. Density functional theory (DFT) calculations determine the adsorption energies of perchlorate on various functional groups of biochar, with pyrrole N exhibiting the highest interaction, followed by -OH, -COOH, graphite N, and pyridine N. Acidic conditions promote stronger electrostatic attraction in the functional groups of biochar. Therefore, the adsorption performance of biochar to perchlorate can be improved by targeted modification of its micropore structure, O-functional groups and pyrrole N structures.

Europium (III) doped bismuth telluride decorated on carbon-based materials for enhancing thermoelectric performance

Scalable synthetic approach for superior performance of thermoelectric (TE) materials is a crucial step for the TE technology progress. Herein, reduced graphene oxide (RGO), carbon nitride (g-C 3N4) and europium (Eu) are utilized as additives to bismuth telluride (Bi2Te3) matrix to prepare various novel nanocomposites (NCs): (RGO@Bi1.8Te3Eu0.2) and (RGO-g-C3N4@Bi1.8Te3Eu0.2) with an enhanced TE performance. The novel NCs were synthesized via solvothermal method, physiochemically characterized and consolidated into pellets of 1 mm thickness to measure their TE properties. The new additives potentially affected the physicochemical and TE properties of Bi2Te3. Nanostructured hexagonal nanoplatelets with 12.5 nm thickness were observed by scanning and transmission electron microscopy (SEM and TEM) of the synthesized Bi2Te3. This thickness shrinked to 5.7 and 5.2 nm upon the formation of (RGO@Bi1.8Te3Eu0.2) and (RGO-g-C3N4@Bi1.8Te3Eu0.2) NCs, respectively. Energy dispersive X-ray Spectroscopy (EDS) of NCs proved the existence of Bi, Te, C, Eu and N atoms. Raman and Fourier-transform infrared (FT-IR) spectra confirmed the NC formation that led to narrowing the energy band gap of Bi2Te3 as displayed by UV–Vis spectra. Brunauer–Emmett–Teller showed specific surface area expansion of Bi2Te3 from 6.78 to 19.00 and 16.75 m2g-1 of (RGO@Bi1.8Te3Eu0.2) and (RGO-g-C3N4@Bi1.8Te3Eu0.2) NCs, respectively. The electrical conductivity of Bi2Te3 rose by 56 and 69 times, whereas its thermal conductivity significantly dropped by 1.6 and 1.7 times upon (RGO@Bi1.8Te3Eu0.2) and (RGO-g-C3N4@Bi1.8Te3Eu0.2) NCs formation. Owing to extra channels of carrier transfer and phonon scattering induced by NCs heterointerfaces. Novel combination of carbon-based materials and Eu with Bi2Te3 matrix boosts its TE performance resulting in a worthy candidate for power generation applications at room-temperature.

Why do children with autism spectrum disorder have abnormal visual perception?

Autism spectrum disorder (ASD) is associated with severe impairment in social functioning. Visual information processing provides nonverbal cues that support social interactions. ASD children exhibit abnormalities in visual orientation, continuous visual exploration, and visual-spatial perception, causing social dysfunction, and mechanisms underlying these abnormalities remain unclear. Transmission of visual information depends on the retina-lateral geniculate nucleus-visual cortex pathway. In ASD, developmental abnormalities occur in rapid expansion of the visual cortex surface area with constant thickness during early life, causing abnormal transmission of the peak of the visual evoked potential (P100). We hypothesized that abnormal visual perception in ASD are related to the abnormal visual information transmission and abnormal development of visual cortex in early life, what's more, explored the mechanisms of abnormal visual symptoms to provide suggestions for future research.

Efficient removal of Congo red and methylene blue using biochar from Medulla Tetrapanacis modified by potassium carbonate

Biochar (BC) prepared from Medulla Tetrapanacis was recognized as having potential in environmental remediation because of its porous texture, abundant chemical surface groups and mineral composition. In this study, a novel modified biochar (KBC) derived from Medulla Tetrapanacis achieved efficient adsorption of Congo red (CR) and methylene blue (MB). Characterization results suggested that the modification had little effect on the group distribution of KBC, but a dramatic expansion of specific surface area was observed on KBC (1180.45 m2/g) compared to BC (198.51 m2/g). KBC exhibited a maximum sorption of 584.17 mg/g for CR and 318.01 mg/g for MB. Kinetic and isotherm studies revealed sorption of CR and MB by KBC was chemosorption, which occurred on the monolayer surface. The comprehensive analysis also provided the basis for the application of KBC to practical production. These outcomes suggested that KBC may become a new option for the effluent treatment.

Investigation of the Impact of High Concentration LiTFSI Electrolytes on Silicon Anodes with Reactive Force Field Simulations

The initial formation cycles are critical to the performance of a lithium-ion battery (LIB), particularly in the case of silicon anodes, where the high surface area and extreme volume expansion during cycling make silicon susceptible to detrimental side reactions with the electrolyte. The solid electrolyte interface (SEI) that is formed during these initial cycles serves to protect the surface of the anode from a continued reaction with the electrolyte, and its composition reflects the composition of the electrolyte. In this work, ReaxFF reactive force field simulations were used to investigate the interactions between ether-based electrolytes with high LiTFSI salt concentrations (up to 4 mol/L) and a silicon oxide surface. The simulation investigations were verified with galvanostatic testing and post-mortem X-ray photoelectron spectroscopy, revealing that highly concentrated electrolytes resulted in the faster formation and SEIs containing more inorganic and silicon species. This study emphasizes the importance of understanding the link between electrolyte composition and SEI formation. This ReaxFF approach demonstrates an accessible way to tune electrolyte compositions for optimized performance without costly, time-consuming experimentation.

Research on the Detection and Measurement of Roughness of Dam Concrete Layers Using 3D Laser Scanning Technology

The roughness of the interlayer concrete, which is an important index for the construction of dams, affects the mechanical properties of the interface between new and old concrete. The traditional monitoring method cannot satisfy field measurements. Therefore, this paper proposes a concrete surface roughness measurement method based on 3D laser scanning technology and implements 3D point cloud calculations. Two layers of specimens with same concrete mix proportion were poured 28 days apart, and a splitting tensile strength test of the superimposed specimen was carried out. Four groups of experiments (MR-S, MR-N, MR-15, and MR-35) tested the interlaminar tensile splitting strength of nine 150 mm cubic specimens on the 3rd, 7th, 14th, and 28th days, respectively. Filling volume, mean amplitude, surface area expansion rate, normal angle std. dev., and curvature std. dev. were measured in the study. The results showed that as the surface roughness of the concrete increased, as did the flushing pressure. The splitting strength of the concrete interface after it solidified increased with age. At 28 days, the splitting strength of MR-15 was higher than that of MR-35. The mean amplitude and the normal angle std. dev. of the rough surface could replace the traditional filling volume index. The new 3D point cloud calculation method for calculating concrete surface roughness was proven by experiments to have good performance.

Investigation on electrochemical performance of striped, β12 and χ3 Borophene as anode materials for lithium-ion batteries

By developing next-generation lithium-ion batteries (LIBS), demand for exploring novel anode materials with exclusive electrochemical features and ultra-high capacity is increasing. In the current research, first-principles theory, and density functional theory (DFT) calculations were conducted to extensively investigate and compare the capability of three different borophene nanolayers, including striped, β12, and χ3 borophene, as a novel candidate for anode electrode in LIBs. We first predicted the most preferential Li atom adsorption sites on the three borophene structures. The predicted average formation energies for striped, β12, and χ3 borophene were obtained 3.123, 3.184, and 3.216 eV, respectively. The positive value of formation energy exhibits the sufficient stability of the structures. Moreover, the negative adsorption energy proved that Li atom insertion on all borophene monolayers is thermodynamically favorable. In order to simulate the lithiation process, we gradually increased the concentration of Li atoms. We found that the fully lithiated striped, β12 and χ3 borophenes could provide ultra-high specific capacities of 1700, 1983, and 1859 mAh/g, respectively. Structural analysis proved that the surface area expansion rate of the striped borophene in a fully lithiated state was 1%, which was lower than those of β12 and χ3 borophene with 3.33% and 2.63%, respectively. The analyses of electronic properties confirmed that borophenes were inherently metallic and superior ion conductive agents, even after fully lithiated state. Ion diffusion was studied using Nudged elastic band method and the value of diffusion energy barrier ranged from 0.03 to 0.36 eV which was lower than other promising 2D anode materials. Furthermore, open-circuit voltage results demonstrated that the electronic potential of modeled borophenes was low enough to be in the acceptable range of under 1.2V. All these reports exhibited that borophene nanolayers with excellent specific capacity and superior conductivity were desired candidates for anode materials of next generation LIBs.

Response of occurrence in microplastics and its adsorped cadmium capacity to simulated agricultural environmental scenarios in sludge-amended soil

Large amounts of microplastics (MPs) enter the soil along with the amendment of sludge to soil. However, it is still unclear about the response of MPs occurrence and the adsorption behaviors of cadmium (Cd)on MPs to typical agricultural environmental scenarios. In present work, three kinds of MPs (polyethylene, polypropylene, and polystyrene) were chosen to investigate that response in three agricultural environmental scenarios with sludge-amended soil, including dry-wet alteration (7 d, five cycles), microbial addition (Bacillus subtilis, 0.05 g/g soil), and Ultraviolet (UV) irradiation (340 nm, 4 × 15 W, 4 d). The results showed that there was the highest adsorption capacity of Cd on MPs (36.21, 45.15, 12.43 μg/g for PE, PP, PS, respectively) after UV irradiation exceeding those from MPs triggered by other two scenarios). UV irradiation caused an increase in the abundance of Streptomyces, an expansion in specific surface area, a significant change in surface morphologies, an improvement in crystallinity or the formation of new crystals, and an enhancement in C–O and CO content, and then resulted in the incremental adsorption capacity of Cd on MPs. The findings are important of significance for controlling the environmental risks from sludge MPs via carrying heavy metals in the soil-plant systems.

PtFe and Fe3C nanoparticles encapsulated in Fe–N-doped carbon bowl toward the oxygen reduction reaction

The high-temperature calcination strategy facilitates the formation of alloy atoms but inevitably results in the aggregation and deactivation of the metal particles for the oxygen reduction reaction (ORR) electrocatalysts. Herein, we report the successful encapsulation of Platinum–Iron (PtFe) nanoparticles (∼4.7 nm) in the N-doped hollow carbon hemisphere matrix (NCB) containing Fe–N and Fe3C without employing high-temperature pyrolysis, which effectively facilitates the well-dispersed Pt nanoparticles and the formation of PtFe nanoalloys. The hollow carbon hemisphere structure contributes to the expansion of the specific surface area and exposure of active sites of the catalyst, meanwhile, the modification of the surface of the carbon nano-bowl from a predominantly Fe to a functional electrocatalyst with a primarily PtFe alloy can boost the ORR catalytic activity and stability. It is found that the Pt3Fe/Fe3C-NCB catalyst exhibits the optimum ORR performance with a mass activity (0.97 A mg−1Pt), 5.10 times higher than the commercial Pt/C (0.19 A mg−1Pt). Pt3Fe/Fe3C-NCB also displays excellent durability in comparison to the commercial Pt/C after 20,000 potential cycles. Combined with the Physical characterization and the electrochemical test results, Fe3C-NCB plays a strong metal-support role for the encapsulated PtFe nanoparticles structure, thereby preventing nanoparticle migration and corrosion. Experimental characterization and theoretical calculations show that the appropriate PtFe alloy composition and the strain effect induced by Fe–N/Fe3C active sites are sufficient to accelerate the detachment of oxygenated species from the alloy surface, resulting in a catalyst with excellent ORR performance.

Treatment of vegetable oil industry wastewater and bioelectricity generation using microbial fuel cell via modification and surface area expansion of electrodes

AbstractBACKGROUNDThis study evaluates the treatment of vegetable oil industry wastewater using dual‐chamber microbial fuel cells (MFCs) via modification and surface area expansion of cost‐effective electrodes. The modified electrodes were applied as both the anode and cathode to investigate their treatment capacity and electrochemical performance. Carbon paper anodes were modified using TiO2‐HX@MWCNT‐COOH‐Al2O3 composite. Activated carbon powders originating from Bambuseae were used as the low‐cost catalyst for the carbon felt cathode. The synthesized catalysts were characterized by Field‐Emission Scanning Electron Microscope (FE‐SEM), Energy Dispersive X‐ray Spectroscopy (EDX), and Brunauer–Emmett–Teller (BET) techniques. The electrochemical properties of the MFCs were investigated by Electrochemical Impedance Spectroscopy (EIS).RESULTSThe highest average removal efficiencies of COD (chemical oxygen demand), BOD5 (5‐day biochemical oxygen demand), NH4+ (ammonium), NH3− (nitrate), TSS (total suspended solids), and VSS (volatile suspended solids) were 94 ± 3% (33 kgCODrem/m3.d), 89 ± 1% (12 kgBODrem/m3.d), 87 ± 1% (0.24 kgNH4+‐Nrem/m3.d), 74 ± 3% (0.05 kgNO3−‐N/m3.d), 79 ± 2% (1 kgCODrem/m3.d), and 65 ± 3% (0.73 kgCODrem/m3.d), respectively. The highest average power density of 30 ± 5 W/m3 was obtained when treating vegetable oil industry wastewater. The highest average coulombic efficiency (CE) of 85 ± 3% and energy efficiency (EE) of 35 ± 2% were achieved. The EIS results showed that the high conductivity and large unique surface area significantly enhanced the charge transfer efficiency on the electrode surface.CONCLUSIONThe results indicated that the TiO2‐HX@MWCNT‐COOH‐Al2O3 composite can be used to reinforce the performance of MFCs. © 2022 Society of Chemical Industry (SCI).

Thermal Stability and Surface Area Modification of Natural Zeolite Through HCl & NaCl Treatment to Apply in Pyrolysis Systems

Pyrolysis technology relies on efficient catalyst materials to expedite the process and improve the quality of the final product. Modified natural zeolite has emerged as a promising heterogeneous catalyst in this regard. This study presents a comprehensive analysis of natural zeolite sourced from Tasikmalaya, West Java, with the primary aim of evaluating its potential as a catalyst. The samples underwent acid treatment procedures and were extensively characterized using BET, TGA, SEM-EDX, X-Ray Diffraction (XRD), and FT-IR tests. XRD results indicated that the predominant frame structure of the Indonesian raw natural zeolite was mordenite, with a Si/Al ratio ranging from 5.0 to 6.0 and a surface area of approximately 23 m²/g. Following the 1M HCl acid treatment, a significant enhancement in the Si/Al ratio to 7.8 and a considerable expansion in surface area to 125.37 m²/g were observed. Moreover, the natural zeolite demonstrated remarkable thermal stability, thus underscoring its potential as a highly suitable catalyst for various pyrolysis applications.

Preparation and characterization of mesoporous Lanthanum-doped bioactive glass nanoparticles

In this study, novel compositions of mesoporous Bioglass (BG) and Lanthanum-doped BG (La-BG) were prepared using the sol-gel method. Microstructure analysis of the produced composites was performed using XRD, FESEM, FTIR, TGA, and BET techniques. The XRD patterns of BG and La-BG show a good match with the combeite phase. The silicate and phosphate groups in the BG and La-BG lattice were detected in FTIR spectra. The BG particles were spherical, with a surface area of 11.54 m2 /g, a pore volume of 0.02491cc/g, and a pore size of 31.35Å. With the addition of La, the BG structure revealed (i) increased crystallinity of diffraction peaks, (ii) the particles changed from a spherical to a petal-like shape with an expansion in surface area and pore volume, and (iii) increased thermal stability of the BG structure. In conclusion, BG's physiochemical characteristics were greatly enhanced by adding La.

Neuroimaging profiling identifies distinct brain maturational subtypes of youth with mood and anxiety disorders

Mood and anxiety disorders typically begin in adolescence and have overlapping clinical features but marked inter-individual variation in clinical presentation. The use of multimodal neuroimaging data may offer novel insights into the underlying brain mechanisms. We applied Heterogeneity Through Discriminative Analysis (HYDRA) to measures of regional brain morphometry, neurite density, and intracortical myelination to identify subtypes of youth, aged 9–10 years, with mood and anxiety disorders (N = 1931) compared to typically developing youth (N = 2823). We identified three subtypes that were robust to permutation testing and sample composition. Subtype 1 evidenced a pattern of imbalanced cortical-subcortical maturation compared to the typically developing group, with subcortical regions lagging behind prefrontal cortical thinning and myelination and greater cortical surface expansion globally. Subtype 2 displayed a pattern of delayed cortical maturation indicated by higher cortical thickness and lower cortical surface area expansion and myelination compared to the typically developing group. Subtype 3 showed evidence of atypical brain maturation involving globally lower cortical thickness and surface coupled with higher myelination and neural density. Subtype 1 had superior cognitive function in contrast to the other two subtypes that underperformed compared to the typically developing group. Higher levels of parental psychopathology, family conflict, and social adversity were common to all subtypes, with subtype 3 having the highest burden of adverse exposures. These analyses comprehensively characterize pre-adolescent mood and anxiety disorders, the biopsychosocial context in which they arise, and lay the foundation for the examination of the longitudinal evolution of the subtypes identified as the study sample transitions through adolescence.

Acute Hypoxia Stress-Induced Apoptosis in Gill of Japanese Flounder (Paralichthys olivaceus) by Modulating the Epas1/Bad Pathway.

The physiological responses and molecular mechanisms of apoptosis in Japanese flounder under hypoxic stress remain unclear. In the present study, we performed acute hypoxia stress on Japanese flounder (2.39 ± 0.84 mg/L) and detected gills responses in histomorphology and molecular mechanisms. The results showed that the volume of the interlamellar cell mass decreased and the gill lamellae prolonged, indicating the expansion of the respiratory surface area. Additionally, the fluorescence signal of apoptosis increased under hypoxic stress. In addition, the expression of two genes (EPAS1 and Bad) related to apoptosis increased about four-fold and two-fold, respectively, at 6 h of hypoxia. Meanwhile, the result of the dual-luciferase reporter assay showed that EPAS1 is a transcription factor, which could regulate (p < 0.05) the expression of the Bad gene, and we identified the binding site of EPAS1 was the AATGGAAAC sequence located near -766. DNA methylation assay showed that hypoxia affected the methylation status of CpG islands of EPAS1 and Bad genes. All results indicated that hypoxia could activate the EPAS1/Bad signal pathway to induce gill apoptosis of Japanese flounder. Our study provides new light on understanding the molecular mechanism of hypoxia-induced apoptosis in Japanese flounder.

PLK4 drives centriole amplification and apical surface area expansion in multiciliated cells.

Multiciliated cells (MCCs) are terminally differentiated epithelia that assemble multiple motile cilia used to promote fluid flow. To template these cilia, MCCs dramatically expand their centriole content during a process known as centriole amplification. In cycling cells, the master regulator of centriole assembly Polo-like kinase 4 (PLK4) is essential for centriole duplication; however recent work has questioned the role of PLK4 in centriole assembly in MCCs. To address this discrepancy, we created genetically engineered mouse models and demonstrated that both PLK4 protein and kinase activity are critical for centriole amplification in MCCs. Tracheal epithelial cells that fail centriole amplification accumulate large assemblies of centriole proteins and do not undergo apical surface area expansion. These results show that the initial stages of centriole assembly are conserved between cycling cells and MCCs and suggest that centriole amplification and surface area expansion are coordinated events.

Global occupation of wetland by artificial impervious surface area expansion and its impact on ecosystem service value for 2001–2018

Wetland is one of the most critical ecosystems with various functions, it produces the highest ecosystem services value (ESV) per unit area among all land types, thus, its decline has become a global concern in recent years. Since the 21st century, many developing countries have been continuously encroaching on wetlands due to rapid economic and population growth, resulting in the replacement of a large number of wetlands by cities, and how to reconcile urban expansion and wetland conservation has become a significant problem that needs to be considered. In this context, we mapped the spatial distribution of wetlands occupied by the expansion of global artificial impervious surface area (ISA) for 2001–2018 and discussed its temporal and spatial change characteristics at the global, continental, and national scales using the annual maps of global annual impervious area data set and global dynamic land cover data set based on Google Earth Engine platform, the loss of ESV due to wetland occupation was also measured at each spatial scale level. The results show that: (1) A total of 1301.24 km2 of wetlands were occupied by ISA expansion globally for 2001–2018, and their interannual variation showed an upward trend for 2001–2015, then began to decline rapidly since 2016. The occupation results in a global loss of US$3.46 billion in ecosystem service value; (2) Asia has the highest loss of ESV due to occupation of wetlands by ISA expansion, 624.18 km2 of occupation of wetlands resulted in a loss of US$1.66 billion in ESV, making it the continent with the largest area of occupied wetlands. Taking into account the different sizes of the continents, Oceania is the continent where ISA expansion occupies the wetlands most, while South America is the continent where it is relatively least severe; (3) China, the USA and Russia account for 50.9 % of global ESV loss due to wetland occupation by ISA expansion, a total of 663.95 km2 of wetlands were occupied. Although countries have made great efforts to protect wetland resources and deal with urban land expansion, our results show that the problem of wetlands occupied by global urban land expansion is still severe.

Decoration of ZnFe2O4 and UiO-66 over g-C3N4 as magnetically novel reusable visible light photocatalyst for degradation of Rh–B

In this research, a unique nanohybrid ternary g-C3N4/ZnFe2O4/UiO-66 (g-C3N4/ZnF/UiO) was successfully prepared applying a hydrothermal synthesis technique. The characteristic properties of the prepared nanocomposite were specified using different characterization methods such as FT-IR, XRD, EDX, SEM, TEM, VSM, GTA, DRS, and BET analysis. The use of zirconium-based (UiO-66) as metal-organic framework has resulted in an expansion in the total surface area of photocatalyst compared to the pure g-C3N4 sample, which has a significant effect on improving Rhodamine B (Rh–B) dye degradation. Maximum efficiency of photocatalytic achievement of the prepared g-C3N4/ZnF/UiO for photodegradation of Rh–B was obtained by using 10 wt% of UiO-66 expose to visible light irradiation for 60 min. The detailed analysis of the structural and degradation outcomes confirmed that the amended photocatalytic degradation performance could be credited to the extremely impressive spatial separation of the charge carriers between suggested materials. The results are also shown that the magnetic property of the synthesized nanocomposites to be enough and useful for separation and collection of the photocatalyst. The nanohybrid ternary can be good recyclability reused for sixth runs without apparent loss of its photocatalytic performance in degrading Rh–B pollutant. Consequently, the ternary g-C3N4/ZnFe2O4/UiO-66 (g-C3N4/ZnF-UiO) prepared nanocomposite can be a favorable replacement for the treatment of dye pollutants in wastewater.

Remodeling of the Plasma Membrane by Surface-Bound Protein Monomers and Oligomers: The Critical Role of Intrinsically Disordered Regions.

The plasma membrane (PM) of cells is a dynamic structure whose morphology and composition is in constant flux. PM morphologic changes are particularly relevant for the assembly and disassembly of signaling platforms involving surface-bound signaling proteins, as well as for many other mechanochemical processes that occur at the PM surface. Surface-bound membrane proteins (SBMP) require efficient association with the PM for their function, which is often achieved by the coordinated interactions of intrinsically disordered regions (IDRs) and globular domains with membrane lipids. This review focuses on the role of IDR-containing SBMPs in remodeling the composition and curvature of the PM. The ability of IDR-bearing SBMPs to remodel the Gaussian and mean curvature energies of the PM is intimately linked to their ability to sort subsets of phospholipids into nanoclusters. We therefore discuss how IDRs of many SBMPs encode lipid-binding specificity or facilitate cluster formation, both of which increase their membrane remodeling capacity, and how SBMP oligomers alter membrane shape by monolayer surface area expansion and molecular crowding.

Experimental investigation of relative roughness height effect in solar air collector with convex dimples

This study focuses on the effect of dimple depth on improving thermal performance in a solar air collector (SAC) with huge convex dimples placed staggered on an absorber. In this regard, convex dimple absorbers with two different types of relative roughness heights, δ/D = 0.16 and δ/D = 0.32, and a flat plate absorber were tested for back-pass and front-pass applications at air mass flow rates of 0.013, 0.027, and 0.036 kg/s. The highest average energy efficiency of 37.9% and 53.5% were achieved for dimpled absorber plates in back-pass and front-pass, respectively, with δ/D = 0.32 at an air mass flow rate of 0.036 kg/s. The exergy efficiency ranged from 8.1% to 12.4% for the back-pass application, whereas it fluctuated from 14.6 to 19.7 in the front-pass application. In comparing δ/D = 0.32 with the flat plate in the back-pass application, Nud/Nuf varied from 1.2 to 1.48 with an increase in Re, while in the front-pass Nud/Nuf changed from 1.13 to 1.37. In the back-pass, Nud/Nuf/(fd/ff) achieved 1.24 in favor of δ/D = 0.32 at Re = 4000, on the other hand, it reached 1.15 in the front-pass. Similarly, the highest Colburn factor values in all Re numbers were obtained in the case of relative roughness height of δ/D = 0.32. As a result, a relative roughness height equal to 0.32 is the optimal geometry for this investigation of a dimpled collector. Accordingly, the results showed that SACs with convex dimples are more successful than the flat plates, thanks to the surface area expansion and turbulence generating ability, which significantly increases the thermal efficiency. This study also recommends the use of a front-pass application.

Interaction of epithelium and myofibroblasts through ERBB3‐PDGF growth pathways crosstalk drive the maturation of distal lung epithelium in late stage lung development

RationaleThe last stage of lung development is realized by coordinated growth of septae from the alveolar walls to subdivide the distal saccules into alveoli, resulting in the expansion of surface area for gas exchange. The process is accompanied by microvascular maturation and underlying matrix formation of the interstitial scaffold. Secondary septation is driven by the orchestration of the distal epithelium, endothelium, and fibroblasts through the spatial and temporal distribution of various growth pathways and their crosstalk.This study investigated the role of the receptor tyrosine kinases 3 (ERBB3) pathway in the fibroblast‐epithelial crosstalk during septation using both in vitro co‐cultures and ex vivo organoid model as well as transgenic mice.MethodsPrimary myofibroblasts were extracted from neonatal C57BL/6wildtype (WT) mice at postnatal day 7 (PND7) and co‐cultured with a murine epithelial cell line (MLE12) in transwell inserts for 24h before sample collection. Gene expression was analyzed by quantitative PCR. Neonatal lung organoids were generated from primary lung epithelial cells (CD45‐/CD31‐) from neonatal C57BL/6 WT mice (PND7) and cultured in matrigel together with primary myofibroblasts from neonatal WT mice (PND7) as well as age matched mice heterozygot for the Platelet‐derived growth factor receptors (PDGF‐Rα+/‐). After organoid formation, cultures were treated with Neuregulin (NRG), an activating ligand of the ERBB3 receptor. We measured organoid number and size and Erbb3 signaling was assessed by immunofluorescence and quantitative gene expression analyses.ResultsProximal culture with myofibroblasts upregulated the expression level of ERBB3 receptor in epithelial cells, as well as homeodomain‐only protein homeobox (HOPX), GATA‐binding factor 6 (GATA6), both of which are essential in the differentiation of distal epithelial cells and surfactant production during late stage lung development. In neonatal lung organoids, myofibroblasts with reduced PDGFRα expression led to reduction in organoid size and number. Treatment with the Erbb3 ligand NRG significantly increased both the expression and phosphorylation of Erbb3 in epithelial cells together with an upregulation of surfactant C (SPC) expression, and an increase in myofibroblasts PDGF‐R α expression.ConclusionActivated Erbb3 signaling results from the interaction with fibroblasts involving PDGF‐Rα signaling and drives distal epithelium maturation.