Spherical Shape Research Articles

Photocatalytic degradation of methylene blue dye using Ba-doped MnO nanoparticles

MnO and Ba-doped MnO NPs were prepared through the chemical reduction method and these NPs were used for the photodegradation of Methylene blue dye (MB) dye in an aqueous medium. The morphological study shows that the MnO NPs have granular shapes while Ba-doped MnO NPs have irregular spherical shapes. XRD results presented that the diameter of MnO and Ba-doped MnO NPs was 30 and 36 nm, respectively. FTIR spectra show peaks in the range of 750–1385 cm−1, which present the metal oxide NPs. The photocatalytic degradation study demonstrated that the MnO and Ba-doped MnO NPs degraded about 73 and 86% dye within 250 min, respectively. The effect of various parameters like pH, initial dye concentration, and catalyst dosage on the photodegradation of dye was also studied. The recovered MnO and Ba-doped MnO NPs also significantly degraded the Methylene Blue dye in aqueous media.

Thiolated chitosan nanoparticles encapsulated nisin and selenium: antimicrobial/antibiofilm/anti-attachment/immunomodulatory multi-functional agent

BackgroundThe increase in the resistance of bacterial strains to antibiotics has led to research into the bactericidal potential of non-antibiotic compounds. This study aimed to evaluate in vitro antibacterial/ antibiofilm properties of nisin and selenium encapsulated in thiolated chitosan nanoparticles (N/Se@TCsNPs) against prevalent enteric pathogens including standard isolates of Vibrio (V.) cholerae O1 El Tor ATCC 14,035, Campylobacter (C.) jejuni ATCC 29,428, Salmonella (S.) enterica subsp. enterica ATCC 19,430, Shigella (S.) dysenteriae PTCC 1188, Escherichia (E.) coli O157:H7 ATCC 25,922, Listeria (L.) monocytogenes ATCC 19,115, and Staphylococcus (S.) aureus ATCC 29,733.MethodsThe synthesis and comprehensive analysis of N/Se@TCsNPs have been completed. Antibacterial and antibiofilm capabilities of N/Se@TCsNPs were evaluated through broth microdilution and crystal violet assays. Furthermore, the study included examining the cytotoxic effects on Caco-2 cells and exploring the immunomodulatory effects of N/Se@TCsNPs. This included assessing the levels of both pro-inflammatory (IL-6 and TNFα) and anti-inflammatory (IL-10 and TGFβ) cytokines and determining the gene expression of TLR2 and TLR4.ResultsThe N/Se@TCsNPs showed an average diameter of 136.26 ± 43.17 nm and a zeta potential of 0.27 ± 0.07 mV. FTIR spectroscopy validated the structural features of N/Se@TCsNPs. Scanning electron microscopy (SEM) images confirmed their spherical shape and uniform distribution. Thermogravimetric Analysis (TGA)/Differential Scanning Calorimetry (DSC) tests demonstrated the thermal stability of N/Se@TCsNPs, showing minimal weight loss of 0.03%±0.06 up to 80 °C. The prepared N/Se@TCsNPs showed a thiol content of 512.66 ± 7.33 µmol/g (p < 0.05), an encapsulation efficiency (EE) of 69.83%±0.04 (p ≤ 0.001), and a drug release rate of 74.32%±3.45 at pH = 7.2 (p ≤ 0.004). The synthesized nanostructure demonstrated potent antibacterial activity against various isolates, with effective concentrations ranging from 1.5 ± 0.08 to 25 ± 4.04 mg/mL. The ability of N/Se@TCsNPs to reduce bacterial adhesion and internalization in Caco-2 cells underscored their antibiofilm properties (p ≤ 0.0001). Immunological studies indicated that treatment with N/Se@TCsNPs led to decreased levels of inflammatory cytokines IL-6 (14.33 ± 2.33 pg/mL) and TNFα (25 ± 0.5 pg/mL) (p ≤ 0.0001), alongside increased levels of anti-inflammatory cytokines IL-10 (46.00 ± 0.57 pg/mL) and TGFβ (42.58 ± 2.10 pg/mL) in infected Caco-2 cells (p ≤ 0.0001). Moreover, N/Se@TCsNPs significantly reduced the expression of TLR2 (0.22 ± 0.09) and TLR4 (0.16 ± 0.05) (p < 0.0001).ConclusionIn conclusion, N/Se@TCsNPs exhibited significant antibacterial/antibiofilm/anti-attachment/immunomodulatory effectiveness against selected Gram-positive and Gram-negative enteric pathogens. However, additional ex-vivo and in-vivo investigations are needed to fully assess the performance of nanostructured N/Se@TCsNPs.

Unveiling the potential: Extracellular vesicles from plant cell suspension cultures as a promising source.

Extracellular vesicles are secreted by all eukaryotic cells and they have an important role in intercellular signaling. Plant extracellular vesicles (PEVs) are a novel area of research that has gained attention due to their potential implications in biomolecule transport and therapeutic applications. PEVs are lipid bilayer-enclosed structures that contain a diverse cargo of biomolecules such as proteins and lipids. Moreover, it is known that PEVs have a noticeable therapeutic potential for various conditions such as inflammation and oxidative stress. However, there are critical problems such as removing the endosomes and plant-derived biomolecules that decrease the standardization and therapeutic efficacy of PEVs. In our study, the aim was to characterize plant cell suspension-derived extracellular vesicles (PCSEVs) obtained from two different plant cell suspension cultures: Stevia rebaudiana and Vaccaria hispanica. These vesicles were isolated using ultrafiltration and characterized with nanoparticle tracking analysis (NTA) and atomic force microscopy (AFM). The molecular composition of PCSEVs was profiled and the cellular uptake assay was performed. Our results demonstrated that PCSEVs have a spherical shape, less than 200 nm. In the fatty acid analysis, the primary components in PCSEVs were palmitic acid, linoleic acid, and cis-vaccenic acid. The protein content of Stevia rebaudiana-derived EVs (SDEVs) was largely associated with proteins involved in extracellular structures and functions. Conversely, Vaccaria hispanica-derived EVs (HDEVs) displayed a higher presence of cytosolic proteins. These findings contribute to the understanding of PCSEVs and open up potential avenues in extracellular vesicle research, pointing to promising prospects for future innovations in various fields.

Cerebroprotective Potential of Andrographolide Nanoparticles: In silico and In vivo Investigations.

Ischemic stroke remains the leading cause of death and disability, while the main mechanisms of dominant neurological damage in stroke contain oxidative stress and inflammation. Docking studies revealed a binding energy of - 6.1 kcal/mol for AG, while the co-crystallized ligand (CCl) exhibited a binding energy of - 7.3 kcal/mol with NOS. AG demonstrated favourable hydrogen bond interactions with amino acids ASN A:354 and ARG A:388 and hydrophobic interactions with GLU A:377. Molecular dynamics simulations throughout 100 ns indicated a binding affinity of - 27.65±2.88 kcal/mol for AG, compared to - 18.01±4.02 kcal/mol for CCl. These findings suggest that AG possesses a superior binding affinity for NOS compared to CCl, thus complementing the stability of NOS at the docked site.AG has limited applications owing to its low bioavailability, poor water solubility, and high chemical and metabolic instability.The fabrication method was employed in the preparation of AGNP, SEM analysis confirmed spherical shape with size in 19.4±5 nm and investigated the neuroprotective effect in cerebral stroke rats induced by 30 min of carotid artery occlusion followed by 4 hr reperfusion, evaluated by infarction size, ROS/RNS via GSH, MPO, NO estimationand AchE activity, and monitoring EEG function. Cortex and hippocampal histology were compared between groups. AGNP treatment significantly decreased Infarction size and increased GSH levels (p<0.01**), decreased MPO (p<0.01**), NO (p<0.01**), AchE (p<0.01**), restored to normal EEG amplitude, minimizing unsynchronized polyspikes and histological data revealed that increased pyramidal cell layer thickness and decreased apoptotic neurons in hippocampus, cortex appeared normal neurons with central large vesicular nuclei, containing one or more nucleoli in compared to AG treatment. Based on brain biochemical, histopathology reports AGNP exhibited significant cerebroprotective activity compared to AG on ischemic rats.

Antimicrobial Activity of Essential-Oil-Based Nanostructured Lipid Carriers against Campylobacter Spp. Isolated from Chicken Carcasses.

Campylobacter is a virulent Gram-negative bacterial genus mainly found in the intestines of poultry. The indiscriminate use of traditional antibiotics has led to drug resistance in these pathogens, necessitating the development of more efficient and less toxic therapies. Despite their complex biologically active structures, the clinical applications of essential oils (EOs) remain limited. Therefore, this study aimed to increase the bioavailability, stability, and biocompatibility and decrease the photodegradation and toxicity of EO using nanotechnology. The diffusion disk test revealed the potent anti-Campylobacter activity of cinnamon, lemongrass, clove, geranium, and oregano EOs (>50 mm). These were subsequently used to prepare nanostructured lipid carriers (NLCs). Formulations containing these EOs inhibited Campylobacter spp. growth at low concentrations (0.2 mg/mL). The particle size, polydispersity index, and zeta potential of these systems were monitored, confirming its physicochemical stability for 210 days at 25 °C. FTIR-ATR and DSC analyses confirmed excellent miscibility among the excipients, and FE-SEM elucidated a spherical shape with well-delimited contours of nanoparticles. The best NLCs were tested regarding nanotoxicity in a chicken embryo model. These results indicate that the NLC-based geranium EO is the most promising and safe system for the control and treatment of multidrug-resistant strains of Campylobacter spp.

Simultaneous production of highly pure hydrogen and carbon nanofibers through COx-free methane dissociation over Ni-based catalysts: Investigation of the promotional effects of transitional metal (Mn, Zr, and Zn)

Hydrogen and carbon nanotubes are two novel and engaging research topics in clean fuel and material science. Methane decomposition is the most advantageous itinerary for the concurrent production of COx-free hydrogen and carbon filaments. The 50Ni/Al2O3 catalyst was successfully fabricated using a simple one-pot hydrothermal method, and the influence of transition metals (Zr, Mn, and Zn) was investigated as the promoter. The homogeneous accumulation of the nanoparticles with a high specific surface area of 101–147 m2.g−1 was revealed to be the consequence of the mesoporous structure's presence. The reactor tests' findings demonstrated that synthesized bimetallic catalysts are more stable and active than monometallic catalysts. Besides, the Zn-modified catalyst was shown to have the highest performance and durability. The maximal methane conversions of 65.7, 77.2, 69.6, and 51.7 % were achieved over the 50Ni-xZn/Al2O3 (defined as 50Ni-xZn/Al2O3; x = 2.5, 5, 7.5, and 10 wt%) at 650 °C and GHSV = 24,000 mL.(h.gcat)−1, respectively. A deeper look at the microstructure and textural characteristics of the aged catalysts makes it clear that the zinc promoter introduced to the 50Ni/Al2O3 sample, by increasing the growth rate of carbon fiber/nanotube, changes the structure of the formed carbons from spherical shape to very homogeneous diameter filaments and lead to the production of ordered carbon filaments with better crystallinity.

Study of Two Synthesized Methods of Gold Nanoparticles Synthesis Using Fresh Flowers Extracts of &lt;i&gt;Clitoria ternatea&lt;/i&gt;

In this research, the syntheses of AuNPs using the flowers extract of butterfly pea (Clitoria ternatea) were studied by two synthesized methods including 1) heating 2) microwave assisted extraction. C. ternatea extract (CT extract) was prepared using the microwave assisted extraction. The best condition for syntheses of AuNPs using CT extract were performed using microwave assisted extraction (1,000 watt for 3 min). The morphology of the synthesized AuNPs from microwave assisted extraction was investigated by transmission electron microscopy (TEM) and X-Ray diffraction analysis (XRD), respectively. The TEM image of synthesized AuNPs also showed that most nanoparticles were in a spherical shape and XRD pattern presented an intense peak at 2θ = 38.44°, 44.41°, 65.03° and 77.58°, respectively which correspond to face centered cubic structure with (111), (200), (220) and (311) plane.

Design and synthesis of dexmedetomidine capped silver nanoparticles: Investigation of its catalytic application for reduction of nitrobenzenes and its effects on anesthetic, anti-inflammatory, antioxidant and analgesic applications

In the present work, the mono-dispersed produced dexmedetomidine capped silver nanoparticles were described. Dexmedetomidine-stabilized silver nanoparticles were prepared from the facile reduction of silver nitrate by NaBH4 as a reducing agent and dexmedetomidine as a stabilizing agent. The successful reduction of Ag+ ions into Ag0 NPs was confirmed by a visual formation of a deep brown color solution and the appearance of λmax nearing 450 nm in the UV–Vis study. The desired Ag NPs/Dexmedetomidine nanocomposite were characterized by various techniques such as UV/Vis, SEM-EDX, TEM and XRD. The abundant amino groups of dexmedetomidine provided the uniform dispersion and nano spherical shape of silver with sizes of 30–40 nm. The Ag NPs/Dexmedetomidine nanocomposite was applied in the catalytic reduction of diverse aromatic nitro functions using sodium borohydride as reducing agent. An excellent yield were achieved within very short reaction time. During the in vivo study, it was noted that the combination of Ag NPs/Dexmedetomidine showed local anesthetic properties in frog and guinea pig models. Additionally, oral administration of Ag NPs/Dexmedetomidine led to a notable decrease in paw edema in mice. The convulsive episodes triggered by acetic acid were markedly decreased in a dose-dependent manner in every group that was administered Ag NPs/Dexmedetomidine treatment. Additionally, the pain-relieving and anti-inflammatory properties of Ag NPs/Dexmedetomidine were assessed at different dosage levels. The data of this research provide evidence for the Ag NPs/Dexmedetomidine potential use as a pain-relieving and anesthetic substances in future investigations and medical trials involving human participants. In the antioxidant assessment, Ag NPs/Dexmedetomidine demonstrated IC50 values of 77 µg/mL against DPPH free radicals.

Molecular Characterisation and Toxicity Analysis of Indigenous Bacillus thuringiensis Berliner Isolates against Cucurbit Fruit Fly Maggots, Zeugodacus cucurbitae (Coquilett) (Diptera: Tephritidae)

Background: Indiscriminate use of insecticides against fruit flies (Tephritidae: Diptera) has led to the development of residue and resistance and there is a need to try alternate eco-friendly management practices. Bacillus thuringiensis (Bt) is the most widely used bacterium forming proteins active against insects of different orders. Thus, the present study was framed to characterize and evaluate 50 indigenous Bt isolates against cucurbit fruit fly maggots, Zeugodacus cucurbitae. Methods: Colony morphology was observed visually, while crystal morphology was observed through a microscope. The cry gene content of the Bt isolates was screened by Polymerase Chain Reaction and the proteins harbored were assessed by SDS- PAGE analysis. Full diet contamination method was used to evaluate the toxicity of Bt isolates against cucurbit fruit fly maggots. Result: Uniform full white, off-white and creamy white colony colours were found except one isolate each, exhibiting full white at centre surrounded by off white and off white at centre surrounded by full white. Spherical shape crystal (45.10%) was predominant followed by cuboidal (29.41%), bipyramidal (17.65%), rectangular (3.92%) and minute crystal attached to spore (3.92%). Insecticidal proteins varied from ~15 to greater than 200kDa in size with one to four and more distinct bands per isolate. PCR screening revealed cry4Aa in 2 isolates, cry4Ba and cry11Aa in one isolate each, cyt1 in 1 isolate. The standard strain Bti 4Q2 (100% mortality of maggots) and the indigenous Bt isolates, T166 (92.59%), T184 (91.11%) and T60 (90.48%) were found to be significantly toxic.

Biomedical Promise of Aspergillus Flavus-Biosynthesized Selenium Nanoparticles: A Green Synthesis Approach to Antiviral, Anticancer, Anti-Biofilm, and Antibacterial Applications.

This study utilized Aspergillus flavus to produce selenium nanoparticles (Se-NPs) in an environmentally friendly and ecologically sustainable manner, targeting several medicinal applications. These biosynthesized Se-NPs were meticulously characterized using X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscope (TEM), and UV-visible spectroscopy (UV), revealing their spherical shape and size ranging between 28 and 78 nm. We conducted further testing of Se-NPs to evaluate their potential for biological applications, including antiviral, anticancer, antibacterial, antioxidant, and antibiofilm activities. The results indicate that biosynthesized Se-NPs could be effective against various pathogens, including Salmonella typhimurium (ATCC 14028), Bacillus pumilus (ATCC 14884), Staphylococcus aureus (ATCC 6538), Clostridium sporogenes (ATCC 19404), Escherichia coli (ATCC 8739), and Bacillus subtilis (ATCC 6633). Additionally, the biosynthesized Se-NPs exhibited anticancer activity against three cell lines: pancreatic carcinoma (PANC1), cervical cancer (Hela), and colorectal adenocarcinoma (Caco-2), with IC50 values of 177, 208, and 216 μg/mL, respectively. The nanoparticles demonstrated antiviral activity against HSV-1 and HAV, achieving inhibition rates of 66.4% and 15.1%, respectively, at the maximum non-toxic concentration, while also displaying antibiofilm and antioxidant properties. In conclusion, the biosynthesized Se-NPs by A. flavus present a promising avenue for various biomedical applications with safe usage.

Melatonin hyalurosomes in collagen thermosensitive gel as a potential repurposing approach for rheumatoid arthritis management via the intra-articular route

Despite the fact that several rheumatoid arthritis treatments have been utilized, none of them achieved complete joint healing and has been accompanied by several side effects that compromise patient compliance. This study aims to provide an effective safe RA treatment with minimum side effects through the encapsulation of melatonin (MEL) in hyalurosomes and loading these hyalurosomes in collagen thermos-sensitive poloxamer 407 (PCO) hydrogels, followed by their intra-articular administration in AIA model rats. In vitro characterization of MEL-hyalurosomes and PCO hydrogel along with in vivo evaluation of the selected formulation were conducted. Particle size, PDI and EE % of the selected formulation were 71.5 nm, 0.09 and 90 %. TEM micrographs demonstrated that the particles had spherical shape with no aggregation signs. Loading PCO hydrogels with MEL-hyalurosomes did not cause significant changes in pH although it increased its viscosity and injection time. FTIR analysis showed that no interactions were noted among the delivery system components. In vivo results revealed the superior effect of MEL-hyalurosomes PCO hydrogel over MEL-PCO hydrogel and blank PCO hydrogels in improving joint healing, cartilage repair, pannus formation and cell infiltrations. Also, MEL-hyalurosomes PCO hydrogel group showed comparable levels of TNF-α, IL1, MDA, NRF2 and HO-1 with the negative control group. These findings highlight the MEL encapsulation role in augmenting its pharmacological effects along with the synergistic effect of hyaluronic acid in hyalurosomes and collagen in PCO hydrogel in promoting joint healing.

An investigation of silver nanoparticles made from plectranthus amboinicus leaves and their antibacterial and photocatalytic activities

In the present research, silver nanoparticles (AgNPs) were prepared utilizing Plectranthus amboinicus using a simple green synthesis process. UV, FT-IR, XRD, TEM, SEM, EDX and DLS were used to characterize the prepared AgNPs. The SPR band appears at 448 nm in the UV–visible spectrum. The FTIR spectrum of the synthesized materials confirmed the presence of potential functional groups in the P.amboinicus leaf extract, as well as silver nanoparticles. The peaks in the PXRD is indexed with the database entry (110) reveals the crystalline nature and the FCC structures of silver nanoparticles. The SEM image reveals the existence of spherical shaped AgNPs, while the EDX image reveals the presence of silver element. TEM pictures indicate the spherical shape of AgNPs with sizes ranging from 20 to 30 nm. Additionally, these biosynthesized NPs photocatalytic activity was investigated against methylene blue under sun irradiation, and after 60 min of exposure, they demonstrated an efficiency of 94 %.Furthermore, the most effective antibacterial agent is Pseudomonas aeruginosa, as evidenced by a 14 mm AgNPs inhibition zone. As a result, we conclude that the synthesized Plectranthus amboinicus AgNPs have more medicinal and industrial potential.

Green synthesis and characterization of magnesium nanoparticles using pumpkin peel extract (Tetsukabuto)

Pumpkin (Tetsukabuto) peel extract was utilized to synthesize nanoparticles of magnesium. The nanoparticles were characterized using scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDS), X-ray diffraction (XRD), selected area electron diffraction (SAED), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), raman spectroscopy (RS) as well as Brunauer-Emmett-Teller (BET) analysis. The results showed that the synthesis of magnesium nanoparticles is possible by use of pumpkin peel extract. The characterization analyses indicated the presence of functional groups on the surface of the nanoparticles, which aided in the bioreduction of the metals to oxides. The nanoparticles can be applied in studies involving microbial agents due to their spherical shape, which allows for easy penetration into the cell wall of microorganisms. This work provides relevant information for the field of nanoparticles and the area of green synthesis.

Virus mimicking liposomes incorporated microneedles delivery platform for efficient skin penetration and enhanced cellular uptake

Transdermal delivery is an attractive route for the treatment of skin disease. However, its therapeutic effectiveness is significantly hampered by the stratum corneum and cell membrane barriers. Herein, we reported a novel liposomes incorporated microneedles (MNs) delivery platform to address these two key challenges. Conventional liposomes were surface modified with membrane-anchoring fusogenic proteins mimicking pH-responsive, comb-like pseudopeptides containing relatively long alkyl side chains. The liposomes-containing MNs were fabricated with biodegradable and biocompatible silk fibroin with sufficient mechanical strength using micromolding technology. The degradation and release profile of liposomes from the MNs delivery platform can be manipulated by controlling the liposomes to silk fibroin ratio, and the released liposomes well-maintained their original spherical shape and pH-responsive functionality. Remarkably enhanced in vitro skin permeation was observed in the polymer modified liposomes incorporating MNs delivery platform compared to the ones without MNs facilitation. Enhanced cellular uptake and potency against cancer cells of the pH-responsive, comb-like pseudopeptides modified liposomes incorporating MNs delivery platform were demonstrated. These results suggest its potential applications for efficient skin penetration and enhanced cellular uptake, which is of crucial importance for skin disease treatment.

Transverse Inscription of Silicon Waveguides by Picosecond Laser Pulses

AbstractIn this work, picosecond laser inscription of segmented waveguides in crystalline silicon based on a deterministic single‐pulse modification process is demonstrated. Pulses of 43 ps duration at 1.55 wavelength are used to transversely inscribe periodic structures with a pulse‐to‐pulse pitch of ≈2 . Infrared shadowgraphy images and Raman spectroscopy measurements indicate that the modifications exhibit a spherical shape. Characterization of waveguide performance at 1.55 for various pulse energies and periods is carried out. Direct comparison with numerical simulations confirms the presence of graded index waveguides, encompassing a micrometer core size and a maximum refractive index change of . This short‐pulse inscription approach can pave the way for 3D integrated photonic devices in the bulk of silicon.

Ophthalmic Nanoemulsion Fingolimod Formulation for Topical Application.

Purpose: Fingolimod (FTY720; FT), a structural analog of sphingosine, has potential ocular applications. The goal of this study was to develop an FT-loaded nanoemulsion (NE; FT-NE) formulation for the efficient and prolonged delivery of FT to the posterior segment of the eye through the topical route. Methods: FT-NE formulations were prepared using homogenization followed by the probe sonication method. The lead FT-NE formulations (0.15% and 0.3% w/v loading), comprising soybean oil as oil and Tween® 80 and Poloxamer 188 as surfactants, were further evaluated for in vitro release, surface morphology, filtration sterilization, and stability at refrigerated temperature. Ocular bioavailability following topical application of FT-NE (0.3%) was examined in Sprague-Dawley rats. Results: The formulation, at both dose levels, showed desirable physicochemical characteristics, a nearly spherical shape with homogenous nanometric size distribution, and was stable for 180 days (last time point checked) at refrigerated temperature postfiltration through a polyethersulfone (0.22 µm) membrane. In vitro release studies showed prolonged release over 24 h, compared with the control FT solution (FT-S). In vivo studies revealed that effective concentrations of FT were achieved in the vitreous humor and retina following topical application of FT-NE. Conclusions: The results from these studies demonstrate that the FT-NE formulation can serve as a viable platform for the ocular delivery of FT through the topical route.

Cu-Doped TiO2 Thin Films by Spin Coating: Investigation of Structural and Optical Properties

Cu-doped TiO2 films were synthesized directly on FTO glass with a spin coating method. With a variation in copper amount, samples were prepared with 0%, 1%, 2%, 4% and 8% of dopant concentrations. Morphological and structural characterization of undoped and Cu-doped TiO2 samples were investigated and the obtained results showed the small, spherical shapes of the nanoparticles forming a thin film on top of FTO glass and their preferred orientation of TiO2 anatase (101), which is the same for each sample. However, this peak exhibited a slight shift for the 2% sample, related to the inflation of the microstrain compared to the other samples. For the optical properties, the 4% sample displayed the highest transmittance whereas the 2% sample exhibited the lowest band gap energy of 2.96 eV. Moreover, the PL intensity seems to be at its highest for the 2% sample due to the present peaking defects in the structure, whereas the 8% sample shows a whole new signal that is related to copper oxide. These properties make this material a potential candidate to perform as an electron transport layer (ETL) in solar cells and enhance their power conversion efficiency.

Thermal regulation enhancement in multi-story office buildings: Integrating phase change materials into inter-floor void formers

Addressing the thermal loss from building envelopes is a crucial challenge and requires the exploration of various mitigation strategies. This study employs comprehensive 3D computational fluid dynamics simulations to investigate the incorporation of various bio-based Phase Change Materials (PCMs) including CrodaTherm (CT) 19, CT21, and CT24W, within inter-floor void formers between the roof-floor boundary in multi-story office buildings to optimize energy management during inactive periods in one of the adjacent units. Aside from the PCM type, the void former shape, its placement, and the combinations of PCMs and insulating layers are examined through heat flux and solid fraction plots as well as liquid fraction contours. Results highlight the exceptional performance of CT24W-integrated void formers, achieving a remarkable 36.74 % reduction in the 48-h average heat flux in comparison with the case without void formers, and offering lower heat flux values than the scenario with insulating layers for 89.38 h (endurance time). Based on the findings, with identical PCM volumes, the semi-ellipsoid PCM-integrated void former provides 11.07 % lower heat flux and 27.56 % longer endurance time compared to the one with a spherical shape. The results underscore PCM integration as a superior strategy over standalone insulation for managing thermal loss between apartment floors.

Flock2: A model for orientation-based social flocking

The aerial flocking of birds, or murmurations, has fascinated observers while presenting many challenges to behavioral study and simulation. We examine how the periphery of murmurations remain well bounded and cohesive. We also investigate agitation waves, which occur when a flock is disturbed, developing a plausible model for how they might emerge spontaneously. To understand these behaviors a new model is presented for orientation-based social flocking. Previous methods model inter-bird dynamics by considering the neighborhood around each bird, and introducing forces for avoidance, alignment, and cohesion as three dimensional vectors that alter acceleration. Our method introduces orientation-based social flocking that treats social influences from neighbors more realistically as a desire to turn, indirectly controlling the heading in an aerodynamic model. While our model can be applied to any flocking social bird we simulate flocks of starlings, Sturnus vulgaris, and demonstrate the possibility of orientation waves in the absence of predators. Our model exhibits spherical and ovoidal flock shapes matching observation. Comparisons of our model to Reynolds’ on energy consumption and frequency analysis demonstrates more realistic motions, significantly less energy use in turning, and a plausible mechanism for emergent orientation waves.

High-stiffness reconfigurable surfaces based on bistable element assembly and bi-compatible truss attachment

Reconfigurable surfaces contribute to multi-task robotic platforms, such as reconfigurable phased array antennas with variable aperture, by morphing between multiple specified shapes. Controlling each tile to approximate the variating shape of target surfaces requires a large number of accurate actuators. Previous research has demonstrated employing bistable-element-assembly to form reconfigurable surfaces for significant actuation simplification but suffering from low out-of-plane stiffness resulting in the lack of load-bearing capacity for carrying functional units with good mechanical accuracy. This paper proposes a design framework for tile-assembling bistable (TAB) surfaces with bi-compatible truss attachment for two prescribable stable configurations. The bistability comes from joining surface tiles with bistable elements, which contributes to easy actuation with fewer inaccurate actuators. Bi-compatible truss structures, which are only kinematically compatible at the two prescribed states, are introduced to enhance the out-of-plane stiffness of the TAB surface and improve its load-bearing capacity. Additionally and consequently, the kinematic determinacy of the reconfigurable surfaces is increased by the truss introduction, where bistable elements control the metric while truss structures dictate the principal curvature of the surface. This diminishes the redundant degrees of freedom with enhanced shape-approximation and reconfiguration-coordination. Four prototypes are designed and manufactured, which are a three-tile by three-tile (3 × 3) TAB surface that is stable at flat and spherical configurations, a 5 × 5 TAB surface with flat and spherical stable configurations, a 3 × 3 TAB surface that is stable at the flat and saddle configurations, and a 3 × 3 TAB surface that is stable at the sphere and saddle shapes. The out-of-plane stiffness, easiness of actuation, and shape accuracy of all prototypes are evaluated and show promises for real engineering applications.