Various Kinds Of Substrates Research Articles

Green Light Triggered Radical Annulation for the Synthesis of Indenone by Metal‐Free Photocatalysis

Low‐energy light, endowing with excellent characteristics of lower energy, fewer side reactions, more abundance in solar light. The scenario has been developed for the fabrication of indenone through a low‐energy green light driven radical annulation reaction between α‐keto acids and internal alkynes using Rhodamine 6G as photocatalyst. Various kinds of substrates are suitable for this methodology, affording the corresponding indenones in a greener and efficient manner.

Self-renewal poly-Schiff base/gallium-based liquid metal composite coatings triggered via water for superior antimicrobial performance under water

Antimicrobial and antifouling coatings, containing either biocides or antibiotics, are extensively employed in medical facilities, marine engineering and various daily settings. Nonetheless, the misapplication of these substances has caused the proliferation of super-resistant bacteria and ecological destruction. While liquid metals present an encouraging option for antimicrobial purposes, the currently available technologies encounter issues associated with particle uniformity and the regulation of Ga3+ release. A water-triggered degradable polymer, namely polyurea-modified poly Schiff base polymer (PIPT), is designed and prepared successfully. The imine bond and urea group of PIPT efficiently generate and stabilize gallium-based liquid metal particles (GLPs). After the solvent evaporation, we obtain a poly-Schiff base/gallium-based liquid metal composite coating (PIPT/G) with a PIPT cover layer measuring approximately 1–2 μm. This cover layer successfully prevents both outflow and contamination of the liquid metal inside. PIPT/G coatings are easily applicable to various kinds of substrates, including fabric, glass and plastic tubes. The degradability of poly-Schiff base materials promotes self-renewal of the coating and control the contact state of water with liquid metal, regulating release of Ga3+. These bifunctional PIPT/G composite coatings exhibit >99 % pathogen eradication by combining antimicrobial action with self-renewal capabilities. This simple yet innovative coating method has the potential to produce highly effective antimicrobial surfaces.

Morphology and biology of Homoplectra gracilis Nozaki, 2019 in a headwater stream in Yata Hills, Japan

Homoplectra Ross, 1938 (Hydropsychidae) comprises 24 species. Knowledge of the immature stages of species in this genus is quite poor. This study aimed to describe for the first time morphology of Homoplectra gracilis Nozaki, 2019 larvae, found in small headwater streams flowing throughout ‘Satoyama’, a unique and important ecosystem in Japan, and clarify its biology. Morphological observations showed that the larva of this species is unique among known Japanese species in having a small median triangular process on the anterior margin of the head. Final instar larvae were found throughout the year, whereas the second instar larvae were observed during July and November. The species retreated using various kinds of substrates; on/between leaves, plants roots, and under stones. Analysis of digestive tracts showed predominantly detritus in their diet along with remains of invertebrates. The larvae appeared to withstand drought which occur in the streams.

Wearable Hydrogel-Based Epidermal Sensor with Thermal Compatibility and Long Term Stability for Smart Colorimetric Multi-Signals Monitoring.

Hydrogel-based wearable epidermal sensors (HWESs) have attracted widespread attention in health monitoring, especially considering their colorimetric readout capability. However, it remains challenging for HWESs to work at extreme temperatures with long term stability due to the existence of water. Herein, a wearable transparent epidermal sensor with thermal compatibility and long term stability for smart colorimetric multi-signals monitoring is developed, based on an anti-freezing and anti-drying hydrogel with high transparency (over 90% transmittance), high stretchability (up to 1500%) and desirable adhesiveness to various kinds of substrates. The hydrogel consists of polyacrylic acid, polyacrylamide, and tannic acid-coated cellulose nanocrystals in glycerin/water binary solvents. When glycerin readily forms strong hydrogen bonds with water, the hydrogel exhibits outstanding thermal compatibility. Furthermore, the hydrogel maintains excellent adhesion, stretchability, and transparency after long term storage (45 days) or at subzero temperatures (-20 °C). For smart colorimetric multi-signals monitoring, the freestanding smart colorimetric HWESs are utilized for simultaneously monitoring the pH, T and light, where colorimetric signals can be read and stored by artificial intelligence strategies in a real time manner. In summary, the developed wearable transparent epidermal sensor holds great potential for monitoring multi-signals with visible readouts in long term health monitoring.

N-acetylglucosaminyltransferase-V requires a specific noncatalytic luminal domain for its activity toward glycoprotein substrates

N-acetylglucosaminyltransferase-V (GnT-V or MGAT5) catalyzes the formation of an N-glycan β1,6-GlcNAc branch on selective target proteins in the Golgi apparatus and is involved in cancer malignancy and autoimmune disease etiology. Several three-dimensional structures of GnT-V were recently solved, and the recognition mechanism of the oligosaccharide substrate was clarified. However, it is still unclear how GnT-V selectively acts on glycoprotein substrates. In this study, we focused on an uncharacterized domain at the N-terminal side of the luminal region (N domain) of GnT-V, which was previously identified in a crystal structure, and aimed to reveal its role in GnT-V action. Using lectin blotting and fluorescence assisted cell sorting analysis, we found that a GnT-VΔN mutant lacking the N domain showed impaired biosynthetic activity in cells, indicating that the N domain is required for efficient glycosylation. To clarify this mechanism, we measured the in vitro activity of purified GnT-VΔN toward various kinds of substrates (oligosaccharide, glycohexapeptide, and glycoprotein) using HPLC and a UDP-Glo assay. Surprisingly, GnT-VΔN showed substantially reduced activity toward the glycoprotein substrates, whereas it almost fully maintained its activity toward the oligosaccharides and the glycopeptide substrates. Finally, docking models of GnT-V with substrate glycoproteins suggested that the N domain could interact with the substrate polypeptide directly. Our findings suggest that the N domain of GnT-V plays a critical role in the recognition of glycoprotein substrates, providing new insights into the mechanism of substrate-selective biosynthesis of N-glycans.

Progress in Spray Coated Perovskite Films for Solar Cell Applications

Spray coating is an emerging technique that can be used to produce large‐area functional films on various kinds of substrates. It is increasingly recognized as a state‐of‐the‐art method for fabricating perovskite films for large‐area, high throughput, and low‐cost perovskite solar cells (PSCs) and modules. Herein, the merits of spray coating and an overview on its application in recent practice are presented. Owing to the key importance of the photoabsorbing perovskite film in PSCs, how one‐ and two‐step spray coating strategies can significantly impact the film quality and overall photovoltaic performance are also discussed. The summary of the recent progress in spray coated PSCs reviewed herein will hopefully serve as a useful guide to the application of this relatively new technique for creating next‐generation perovskite‐based photovoltaics.

Versatile snail-inspired superamphiphobic coatings with repeatable adhesion and recyclability

Superamphiphobic surfaces with extreme repellency toward both water and oily liquids have been developed from various nanocomposites with fluorinated compounds. However, the inherent rigidity and low-surface-energy of these composites restrict their adhesion and practical application in adjusting the surface wettabilities of materials. Here we report a strategy to create hybrid superamphiphobic coating with rapid contact adhesion to various kinds of substrates, strong and controllable adhesive strength, unprecedented capability of mechanical deformations, facile removal, repeatable adhesion, and simple recyclization. Our approach, inspired by snail’s ideal combination of hard shell and soft epiphragm, is versatile and industrially-viable because we use the hydrogel primer to bond the fluorinated nanoparticle finish and substrates. Considering the unique characteristics of these coatings as well as the wide range of available hydrogels and nanomaterials that can be used via this approach, we envision that this snail-inspired strategy will facilitate the development and large-scale production of superamphiphobic coatings.

Superhydrophobic and self-healing dual-function coatings based on mercaptabenzimidazole inhibitor-loaded magnesium silicate nanotubes for corrosion protection of AZ31B magnesium alloys

In this work, clinochrysotile-like magnesium silicate nanotubes (MS-TNs) were fabricated by a hydrothermal method and then modified with dodecyltrimethoxysilane (DTMS) for the first time to act as a superhydrophobic material (MS-TNs/DTMS), whilst the MS-TNs was used as a nanocontainer to load a corrosion inhibitor 2-mercaptabenzimidazole (2-MBI). Taking the advantage of epoxy resin as a coating matrix, the AZ31B Mg alloy substrate was coated successfully by MS-TNs(2-MBI) as the first layer (for self-healing anti-corrosion) and superhydrophobic MS-TNs/DTMS as the second layer (for superhydrophobicity and anti-corrosion). The wettability, functionality and physicochemical stability of the superhydrophobic surface as well as the anti-corrosion performances of the dual-function coatings were systematically investigated by characterization, testing and electrochemical measurements. The as-prepared dual function coating with water contact angle at about 155° and sliding angle at circa 5° not only showed robust mechanical stability and chemical durability, but also exhibited substantial improvement of anti-corrosion property for protection of AZ31B Mg in a long run. The corrosion current density decreased from 8.33 × 10−4 A·cm−2 of bare Mg to 8.12 × 10−8 A·cm−2 of the coated sample. Furthermore, MS-TNs/DTMS was applicable to various kinds of substrates (e.g., copper mesh, sponge, glass slide, cloth, A4 typing paper) and showed an excellent water repellency, demonstrating its potential usage in fabrication of superhydrophobic surface as a low-cost and environmentally-benign material.

Influence of preparation conditions on the properties of silver doped copper-zinc sulfide thin films prepared via sol-gel spin coating technique

This work reports the preparation of Ag/Cu-Zn-S nanocomposite thin films using a sol-gel spin coating technique without sulfurization. For comparison, a pure Cu-Zn-S (CZS) sample, as well as CZS embedded with silver nanoparticles of various thicknesses, grown on heated substrates at 280 °C and 320 °C, were well fabricated. Several films like pristine CZS and Ag/CZS with different Ag % (0.5, 1, and 2 %) were deposited on various kinds of substrates like glass, n-type and p-type silicon with 5 and 8 layer thicknesses. The impact of annealing temperature 320 °C of the prepared film on the surface morphology, optical, structural, and electrical properties of the deposited films on various kinds of substrates were investigated. The field emission scanning electron microscopy images displayed homogeneous spreading with a smooth uniform surface of the substrates. Formation of Nano-rods (≈ 600 nm) dimension of the deposited pristine film with 5 layers on n-Si and annealed at 320 °C was observed. The energy dispersive spectroscopy results confirmed that a trace amount of metals was presented in the film. The X-ray diffraction for pristine and Ag/CZS films depicted peaks confirming to the polycrystalline of hexagonal and cubic crystal structure. It was observed that the optical bandgap energy (Eg) reduces with increasing the thickness of the film. The values of the index of refraction (n), high frequency and optical static dielectric constants (ε͚, ε˳) of deposit films on Si and glass substrates through the calculation of Eg as a function of the Ag concentrations were also calculated.

Impact of silver dopants on structural, morphological, optical, and electrical properties of copper-zinc sulfide thin films prepared via sol-gel spin coating method

Abstract In recent days, Eco-friendly nano-composite thin film employed as an absorber layer in solar cells is one of the most worthy kind of industrial semiconductors and a variety of optoelectronics and optical device applications. Thus, nano-composite samples of copper-zinc sulfide (Cu-Zn-S) embedded with silver dopants (Ag) were perfectly synthesized using 280 °C temperature and low-cost sol-gel spin coating technique without sulfurization. For this objective, several films like pristine (S0) and Ag-doped Cu-Zn-S with different Ag concentrations 0.5% (S1), 1% (S2) and 2% (S3) were deposited on various kinds of substrates like glass, n-type and p-type silicon (Si) with 5 and 8 layer thicknesses. The impact of Ag concentration and the thickness of the prepared film on the surface morphology, structural, electrical, and optical properties of the deposited films on glass substrates were elaborated. It was found that both pristine and Cu-Zn-S films doped with various concentrations of Ag depict the polycrystalline structure of hexagonal and cubic crystal structure using X-ray diffraction. The images of the SEM (scanning electron microscopy) displayed excellent compatibility, homogeneous spreading with a smooth uniform surface, and cover all the areas of the substrates, especially the 1% Ag/Cu-Zn-S film with the structure of less porosity. The results of ICP-OES (inductively coupled plasma-optical emission spectroscopy) and EDS (energy dispersive spectroscopy) were investigated to identify the composition of the forming elements. The optical properties of pristine and Ag-doped films with 5 and 8 layer thicknesses were reported. It was found that for 5 layer deposition at 280 °C, the optical bandgap energy (Eg) reduces from 2.29 eV (S0) to 2.09 eV at 2% Ag/Cu-Zn-S (S3) films. While for 8 layer deposition, the Eg decreases from 2.16 eV (S0) to 1.91 eV at 2% Ag/Cu-Zn-S (S3) films. Hence it can be concluded that the Eg decreases with increasing the thickness of the film, which is in agreement with the achieved results in the literature. In addition, it was observed that the 1% Ag/Cu-Zn-S (S2) film has the lowest resistivity value of 0.66 Ω cm at 280 °C. From all measurements obtained by depositing films on glass substrates, we select the best films to be deposited on n- and p-types Si substrates to study the impact of the n- and p-types silicon substrates on the properties of our films. We also calculated the values of the index of refraction (n), high frequency and optical static dielectric constants (e, e˳) of deposit films on Si and glass substrates through the calculation of Eg as a function of the silver concentrations.

Facile preparation of compact LTA molecular sieve membranes on polyethyleneimine modified substrates

A facile preparation strategy was proposed for preparation of compact zeolite LTA membranes on polyethyleneimine (PEI) modified substrates without seeding. Through the functionalization of substrates by using PEI, compact LTA membranes can be formed on various kinds of substrates. A well-intergrown and phase-pure LTA membrane with a thickness of about 3.0 μm is successfully prepared on the α-Al2O3 disk after crystallization for 24 h at 60 °C. Besides LTA membrane, well-intergrown zeolite FAU membranes can also be formed on PEI-modified α-Al2O3 substrates, suggesting the universality of this strategy. The zeolite LTA membranes synthesized on PEI-modified α-Al2O3 tubes were evaluated for the separation of alcohols/water mixture through pervaporation. The as-synthesized zeolite LTA membranes display high pervaporation performances. For the separation of 10 wt% iso-propanol/water solution at 90 °C, a high separation factor of 44991 and a water flux of 1.73kgm−2h−1 are achieved.

Fabrication and growth mechanism of ultra-crystalline C60 on silicon substrate in vacuum

We report a simple procedure to fabricate single crystals 3D C60 having an FCC structure on silicon substrates using a vapour–solid set-up in vacuum conditions. The morphology of the deposited film can be tuned by controlling the temperature and position of the substrate. The as-fabricated samples are extensively characterised by transmission electron microscopy, scanning electron microscope, X-ray powder diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and nano-indentation, which allow us to shed light on the recrystallization process of the C60. In addition, the growth mechanism of the formation of crystalline 3D structure of the C60 film is discussed in detail. Based on the newly gained knowledge of mechanism and its unique properties, fullerene has shown huge potential as a solid lubricant on various kinds of substrates.

Polystyrene Encapsulated SERS Tags as Promising Standard Tools: Simple and Universal in Synthesis; Highly Sensitive and Ultrastable for Bioimaging.

Surface coating determined the sensitivity and stability of surface-enhanced Raman scattering (SERS) tags in bioanalysis. The reported various coatings suffered from the drawbacks of a lack of rigidity, stability, or synthesis versatility. Herein, we demonstrated robust polystyrene (PS) coated SERS tags that could be prepared by an easy and universal approach. Taking advantages of biocompatible, transparent, compact properties of PS shell, the coated tags showed satisfactory sensitivity, biocompatibility, and superior structural stability in cell and in vivo imaging applications. More importantly, the PS coating strategy allowed for the encapsulation of SERS tags encoded with not only thiolated but also nonthiolated Raman reporters without loss of sensitivity, as exemplified in the synthesis of 9 different resonant dye-encoded tags. Moreover, the coating of SERS tags with various kinds of substrates was achieved via the same standard protocol. Comparing with widespread silica coated tags, the PS coated ones were more stable in harsh conditions and had an easily expanded ultrasensitive (resonant) tags library with much lower cost (no need of expensive sulfhydryl/isothiocyano reporters with limited types), illustrating great promise as standard analytical tools of commercialized value for bioanalysis, medical diagnostics, and environmental science studies.

Half‐sandwich ruthenium‐based versatile catalyst for both alcohol oxidation and catalytic hydrogenation of carbonyl compounds in aqueous media

A series of half‐sandwich ruthenium‐based catalysts for both alcohol oxidation and carbonyl compounds hydrogenation have been synthesized through metal‐induced C–H bond activation based on benzothiazole ligands. The neutral ruthenium complexes 1–4 were fully characterized by UV–vis, NMR, IR, and elemental analysis. Molecular structures of complexes 1 and 3 were further confirmed by X‐ray diffraction analysis. All complexes exhibited high activity for the catalytic oxidation of a variety of alcohols with tBuOOH as oxidants to give carbonyl compounds with high yields in water. Moreover, these half‐sandwich complexes also showed high efficiency for the catalytic hydrogenation of carbonyl compounds in a methanol–water mixture. The catalyst could be reused for at least five cycles without any loss of activity. The catalytic system also worked well for various kinds of substrates with either electron‐donating or electron‐withdrawing groups.

Cyclometalated Half-Sandwich Iridium Complex for Catalytic Hydrogenation of Imines and Quinolines

Several C,N-chelate cyclometalated half-sandwich iridium-based catalysts for imines and quinoline derivatives reduction have been prepared through metal-mediated C–H bond activation based on benzothiazole ligands. These iridium complexes exhibited high catalytic activity for hydrogenation of various types of imines with high yields. The most active catalyst was obtained from methoxyl substituted complex 2, showing the catalytic TOF value of 975 h–1 for the reduction of imine 6a. Additionally, these half-sandwich complexes also showed high efficiency for the catalytic hydrogenation of N-heterocyclic quinoline derivatives. Good catalytic activity was displayed for various kinds of substrates with either electron-donating or electron-withdrawing groups. Complexes 1–5 were fully characterized by NMR, IR, and elemental analysis. Molecular structures of complexes 1 and 4 were further confirmed by X-ray diffraction analysis.

Solvent-Free Deposition of Ultrathin Copolymer Films with Tunable Viscoelasticity for Application to Pressure-Sensitive Adhesives.

A new fabrication method for an ultrathin (500 nm thick) pressure-sensitive adhesive (PSA) was demonstrated by utilizing a series of in situ cross-linked viscoelastic copolymer films. Viscoelastic films composed of poly(2-hydroxyethyl acrylate- co-2-ethylhexyl acrylate) were synthesized successfully in a one-step manner by an initiated chemical vapor deposition (iCVD) process, where free-radical polymerization is triggered in the vapor phase either by heat or UV, or a combination of both. In particular, the photoinitiated chemical vapor deposition method generated a highly cross-linked polymer film, whereas cross-linking of the copolymer film was suppressed greatly in the conventional thermal iCVD method. A combination of thermal and photoinitiated chemical vapor deposition could regulate the cross-linking density of the copolymer films. We controlled the cross-linking density of the copolymer films to exhibit a viscoelastic property so that they would readily adhere to various kinds of substrates with only 500 nm thick copolymer PSA. The adhesion performance of the PSA was systematically optimized by tuning the copolymer composition as well as the cross-linking density, and consequently a high shear strength of more than 85.2 ± 5 N/cm2 was achieved despite the 500 nm thickness. In addition, the PSA was completely transparent. We expect that the ultrathin PSAs developed in this work will be utilized widely for the realization of various soft electronic devices, which usually require strong adhesion, tunable viscoelastic properties, and optical transparency.

A comparative study on the enhanced operation of a BFB and SFCW coupling process for domestic wastewater treatment

In this study, a new coupling process system of BFB (biological filter bed) and SFCW (subsurface-flow constructed wetland) based on the auto-ventilation network was proposed, and the comparative pollutant removal efficiency of the pilot test coupling system with different substrates configurations were investigated. The study found that: the influent concentration of the system fluctuated greatly and effluent concentration of the comparison system (b) was 20.22 ± 13.37 mg/L, 2.70 ± 2.49 mg/L, 4.40 ± 3.05 mg/L and 1.09 ± 0.62 mg/L, respectively. The comparison system (b) had better removal rates than that of the original system (a), which was 81.30 %, 90.28 %, 88.57 % and 75.36 % for CODcr, NH4+-N, TN and TP, respectively. The removal of the above main water indexes of the comparison system (b) promoted to 4.20 %, 9.20 %, 7.66 % and 13.61 % respectively when compared to the original system (a), which showed that the optimized configuration of various kinds of substrates was significant and was more beneficial to the degradation and removal of pollutants. The adsorption and interception function of substrates in the constructed wetland was the main way of phosphorus removal. The function of auto-ventilation ensured the amount of DO in the coupling system, making the phosphorus removal was less affected comparing to structure of traditional wetland.

Study on the Enhanced Operation of Self-Ventilation-Based Coupling System for Domestic Wastewater Treatment

In this study, a new coupling system of biological filter bed and subsurface-flow constructed wetland based on the self-ventilation network was proposed, and the comparative pollutant removal efficiency at low and high influent concentration of the pilot coupling system with different substrates configurations were investigated. The study found that: The comparison system (b) had better removal rates than that of the original system (a), and the removal rate when treating low influent concentration was 74.10%, 94.14%, 73.57% and 69.53%, while in high influent concentration case was 81.30%, 90.28%, 88.57% and 75.36% for CODCr , NH4+ -N, TN and TP, respectively. The removal of the above main water indexes of the comparison system (b) promoted by 11.00%, 11.55%, 2.69% and 8.09% respectively in low influent concentration case and 4.20%, 9.20%, 7.66% and 13.61% respectively in high influent concentration case when comparing to the original system (a), which showed that the optimized configuration of various kinds of substrates was significant and was more beneficial to the degradation and removal of pollutants. The adsorption and interception function of substrates in the constructed wetland was the main way of phosphorus removal. The function of self-ventilation ensured the amount of DO in the coupling system, making the phosphorus removal was less affected comparing to structure of traditional wetland.

Large-Area and Transferred High-Quality Three-Dimensional Topological Insulator Bi2-xSbxTe3-ySey Ultrathin Film by Catalyst-Free Physical Vapor Deposition.

Uniform and large-area synthesis of bulk insulating ultrathin films is an important subject toward applications of a surface of three-dimensional topological insulators (3D-TIs) in various electronic devices. Here we report epitaxial growth of bulk insulating three-dimensional topological insulator (3D-TI) Bi2-xSbxTe3-ySey (BSTS) ultrathin films, ranging from a few quintuple to several hundreds of layers, on mica in a large-area (1 cm2) via catalyst-free physical vapor deposition. These films can nondestructively be exfoliated using deionized water and transferred to various kinds of substrates as desired. The transferred BSTS thin films show good ambipolar characteristics as well as well-defined quantum oscillations arising from the topological surface states. The carrier mobility of 2500-5100 cm2/(V s) is comparable to the high-quality bulk BSTS single crystal. Moreover, tunable electronic states from the massless to the massive Dirac fermion were observed with a decrease in the film thickness. Both the feasible large-area synthesis and the reliable film transfer process can promise that BSTS ultrathin films will pave a route to many applications of 3D-TIs.

Structural Study of Silica Coating Thin Layers Prepared from Perhydropolysilazane: Substrate Dependence and Water Penetration Structure

The structure of perhydropolysilazane (PHPS)-derived silica (PDS) waterproof thin layers synthesized by curing at 60 °C for 1 h and allowed to stand for 48 h at 20 °C on various kinds of substrates was studied. Neutron reflectivity (NR) analysis suggested that uniform PDS thin layers were synthesized on the substrates, and the density of the layers varied depending on the type of substrate. Additionally, since the change in PDS density is correlated with the pKa value of the OH group on the substrate, it can be suggested that the acidity of the substrate would be one of the main factors determining the density of the coated PDS thin layers. For the water penetration structure study, NR analysis revealed that the depth of water penetration into the PDS layers was below 500 Å, and the hydration number of the SiO2 molecule was estimated to be 8.0–9.0. From these results, we concluded that water penetration occurred by the formation of water-pool structures in the PDS layers, and the randomly formed nano-air holes lead to a reduction in the probability of water penetration into the deep regions of the PDS layers.