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In an effort for further improvement of LSCF hollow fiber membrane properties in oxygen purification application, this work studied the use of polyethylene glycol (PEG) with different molecular weight of 2000, 3400 and 6000 Da as a pore former. A well-prepared hollow fiber membrane was successfully fabricated via extrusion followed by a sintering method. The results showed that the addition of PEG increased the viscosity of the dope suspension and formed a constant asymmetric pore configuration of the membrane after sintering at 1250 °C. The increasing molecular weight of PEG also leads to a decrease in the mechanical strength of the membranes, indicating that finger-like pores were sacrificed by forming irregular pores. The gas tightness was also examined under room temperature which showed that membrane with PEG 3400 achieved the best tightness with the nitrogen permeability of 3.55 × 10−5 mol·m−2·s−1·Pa−1. The oxygen permeation of the membranes was also influenced by the addition of PEG, where the highest oxygen permeation flux of 6.07 × 10−8 mol·cm−2·s−1 was obtained using a hollow fiber membrane with PEG 3400 due to the existence of the lowest dense layer thickness.

Chitosan (CS) is a natural and biopolymer that are suitable biomedical properties such as; biocompatibility, non-toxicity, biodegradability and bioactive polymer that’s reason with a very large application (fabrication of biomedical scaffolds, implants). Some of the biocompatible thermoplastic polymers (PLA, PEEK, PLGA, PE, PP, PMMA, PET and etc.) are most widely used in biomedical field as per their properties from last two decades. Poly-vinyl chloride (PVC) thermoplastic polymer are most widely used in medical field but there are some limitations of their uses. For enhancement of PVC thermoplastic polymers properties sometimes add some bioactive and biocompatible fillers or other bioactive thermoplastic polymers. In this review paper try to link and discussed about the possible reinforcement CS in PVC thermoplastic polymer for biomedical applications.

In this study we report a facile, cost effective one step preparation method for the synthesis of Mn doped cerium oxide (CeO2) nanoparticles (NPs) through co-precipitation technique. The synthesis was performed at relatively low temperature using a green reagent oxalic acid as reducing agent. The structural and optical attributes of the samples were characterized by X-Ray Diffraction spectroscopy (XRD), Fourier Transform Infrared Spectroscopy (FTIR), UV–Visible spectroscopy and SEM (Scanning electron microscopy). The XRD and FTIR results show the formation of Mn doped ceria NPs having a cubic fluorite structure. The morphology and chemical composition of the prepared sample was realized using SEM and EDX spectrum. The synthesized Mn doped ceria NPs shows greater absorption in the visible region and reduced particle size compared to pure ceria NPs.

Soft gamma ray irradiation is done on Silver nano colloids prepared using Pepper Nigrum as reducing and stabilizing agent. Change in surface morphology and the structure of the colloid is obtained from Transmission Electron Microscope images and Selected area Electron Diffractogram. Morphology of the gamma irradiated sample is devoid of nano particle clusters and the Selected Area Electron Diffraction pattern confirms the crystal nature as face centered cubic structure of nano silver. UV–visible spectroscopic analysis gives the absorption peaks in the green region. Gamma irradiation results in the reduction in peak intensity without any change in wavelength. A statistical approach is done on treating the gamma irradiated colloidal sample with the as prepared silver nano colloid for measuring the area of affecting fungal infection on a potato-agar medium. It is found that the fungal growth is declined rapidly with the introduction of gamma irradiated silver nano colloid than the as prepared colloid.

The rapid degradation of magnesium (Mg)-based implants in physiological environment limits its clinical applications, and alloying treatment is an effective way to regulate the degradation rate of Mg-based materials. In the present study, three Mg alloys, including Mg-0.8Ca (denoted as ZQ), Mg-0.8Ca-5Zn-1.5Ag (denoted as ZQ71) and Mg-0.8Ca-5Zn-2.5Ag (denoted as ZQ63), were fabricated by alloying with calcium (Ca), zinc (Zn) and silver (Ag). The results obtained from electrochemical corrosion tests and in vitro degradation evaluation demonstrated that the three Mg alloys exhibited distinct corrosion resistance, and ZQ71 exhibited the lowest degradation rate in vitro among them. After addition of Zn and Ag, the antibacterial potential of Mg alloys was also enhanced. The in vitro cell experiments showed that all the three Mg alloys had good biocompatibility. After implantation in a rat femoral defect, ZQ71 showed significantly higher osteogenic activity and bone substitution rate than ZQ63 and ZQ, due to its higher corrosion resistance as well as the stimulatory effects of the released metallic ions. In addition, the average daily degradation rate of each Mg alloy in vivo was significantly higher than that in vitro, as could be due to the implantation site located in the highly vascularized trabecular region. Importantly, the correlations between the in vitro and in vivo degradation parameters of the Mg alloys were systematically analyzed to find out the potential predictors of the in vivo degradation performance of the materials. The current work not only evaluated the clinical potential of the three biodegradable Mg alloys as bone grafts but also provided a feasible approach for predicting the in vivo degradation behavior of biodegradable materials.

A series of bender element tests was carried out to investigate the variation of small-strain stiffness (Gmax) of sand–granulated rubber mixtures under long-term loading. Comparisons were made using two different host sands: a non-crushable material called Sydney sand and a crushable material composed of completely decomposed volcanic rock (CDV). The test results suggested that, at the selected stress states in the study (mean effective confining stress ranged from 250 to 333 kPa), the influence of creep on the stiffness of the pure sand specimens was more pronounced for CDV compared with Sydney sand and the presence of rubber amplified creep effects on both types of mixtures. The influence of creep on Gmax was therefore associated with two major mechanisms: the increased compressibility of specimens predominantly because of grain crushing (contribution of sand fraction), and the increased compressibility because of the presence of soft rubber grains (contribution of the rubber fraction). The significant influence of grain breakage on the relationship between stiffness and creep was confirmed by post-test examination of the grain-size distribution curves of pure CDV samples. For rubber–CDV mixtures, the inclusion of soft and viscoelastic rubber grains prevented breakage, in this way reducing the creep mechanism due to grain crushing, but increased the overall influence of creep on stiffness. These conclusions were drawn based on 20% of rubber by mixture weight, and very similar behaviour was observed for 10% rubber. It was therefore understood that the aggravation of creep induced by the increased deformations due to the presence of rubber, for the given contents of rubber included in the study, was more dominant compared with the adverse influence of rubber on samples’ creep by preventing sand grain breakage.

Biodegradable magnesium alloys have excellent properties with respect to biodegradability, biocompatibility, and biomechanics, which may indicate a possibility of its application in intestinal stents. Investigation of Mg-Zn-Y-Nd alloy's application in intestinal stents has been performed. This study aims to investigate the degradation behavior of Mg-Zn-Y-Nd alloy intestinal stents coated with poly(L-lactide)/paclitaxel in the intestinal environment and its biocompatibility with intestinal tissue. In this paper, Mg-Zn-Y-Nd alloy's corrosion properties were evaluated by the immersion test in human feces, SEM and XRD, and animal tests. In vitro results showed that when the Mg-Zn-Y-Nd alloy was immersed in human feces for two weeks, its corrosion resistance could be improved by micro arc oxidation (MAO) and poly-l-lactide (PLLA) dual coating. Additionally, this result was also confirmed in vivo experiments by rabbit model. And animal tests also demonstrated that the Mg-Zn-Y-Nd alloy with MAO/PLLA/paclitaxel dual coating drug-eluting stents could inhibit the proliferation of local intestinal tissue around the stents. However, in vivo studies illustrated that the intestinal stents gradually degraded in rabbit model within 12 days. Considering the degradation rate of the stent was faster than expected in rabbits, the support performance of the scaffold requires further improvement.

Hydroxyl terminated poly(dimethylsiloxane) (PDMS-HT) is used as an electrolyte additive in electrolyte systems containing 1 M LiPF6 in EC:DMC (ratios 1:9; 3:7; 4:6 and 1:1 v/v) to enhance the cycle performance of lithium-ion batteries. Adding a small amount of PDMS-HT to the standard LIB electrolyte leads to improved specific capacity as well as improved capacity retention over prolonged cycles. There is also a slight increase in Li+ ion conductivity when PDMS-HT is added. Also, the PDMS-HT additive allows the formation of a more stable solid electrolyte interface (SEI) layer that enables the LIB cells to be cycled for longer cycles with minimal capacity fading. This combination of improved ionic conductivity and stable SEI layer formation due to the PDMS-HT additive, makes it an excellent candidate for an electrolyte additive for lithium ion batteries.

Chitosan-coated Fe3O4 nanoparticles were prepared by coprecipitation followed by reaction with chitosan and different volumes of glutaraldehyde. Coating was modified by varying the volume of glutaraldehyde and reaction time. XRD pattern shows maxima compatible Fe3O4 structure. FTIR spectroscopia confirms the presence of chitosan, more evident in samples with higher chitosan content, as denoted by TGA. TEM images of samples with low glutaraldehyde content reveal particles coated with a homogeneous chitosan shell. Meanwhile, those prepared with high glutaraldehyde volume show nanoparticles dispersed in an organic matrix. Samples present almost superparamagnetic behavior with magnetization saturation values that are reduced as the content of organic matter increases. Regarding the stability of these samples in solution, the presence of a homogeneous coating improves the initial suspension, although it does not prevent its subsequent aggregation over time. However, this aggregation process is reduced for sample synthesized with 1 mL of glutaraldehyde after 6 h of reaction.

The present work reports the results of the lignin molecule degradation studies using nitrogen-doped ZnO photocatalysts supported on graphene oxide. Three different nitrogen precursors were used to achieve the nitrogen doping in ZnO, namely urea, ethylenediamine, and thiourea, using a microwave-assisted hydrothermal method. Our purpose is to demonstrate that different nitrogen precursors give rise to different amounts of doping in ZnO, which in turn, favorably affects their photocatalytic behavior. The synthesized compounds were tested on the lignin degradation reaction, under visible (Vis) and ultraviolet (UV) energy irradiation. Structural and physicochemical properties of prepared samples were investigated to provide explanation of the photocatalytic behavior observed in samples. XPS analyses were developed to determine differences in nitrogen content, as well to determine the proportion of N-N or O-Z-N binding in samples. Remarkable structural and photocatalytic differences were found for every sample as effect of the nitrogen precursor. Photocatalytic activity tests revealed that the percentage of lignin degradation under UV irradiation was 80 %; while using Vis energy the degradation value was 61 %.

A novel castor-oil-based and phosphorus-containing epoxy resin (flame-retardant epoxy resin (FREP)) and a curing agent – castor oil polybasic acid (AACO) – with high flame retardancy and flexibility were successfully synthesized. The chemical structures of FREP and AACO were characterized by Fourier transform infrared spectrometry (FTIR) and hydrogen-1 (1H) nuclear magnetic resonance spectroscopy. The epoxy resin components were prepared by using bisphenol A epoxy resin (diglycidyl ether of bisphenol A (DGEBA)) with different mass contents of FREP and AACO. DGEBA with 40 wt% FREP (FREP40) possessed a large limiting oxygen index of 29.3%. Cone calorimetry showed that the heat release and smoke production were reduced for both DGEBA with 20 wt% FREP (FREP20) and FREP40 in comparison with those of pure resin (FREP0), indicating that the smoke release and fire hazard of epoxy resin composites with FREP were reduced. Thermogravimetry–infrared spectroscopy suggested that the yields of toxic carbon monoxide (CO), carbon dioxide (CO2) and other pyrolysis products were significantly reduced. FTIR and X-ray photoelectron spectroscopy showed that FREP40 outperformed FREP0 in carbon-forming capacity. The introduction of FREP and AACO effectively increased the elongation at break of pure epoxy resins. FREP and AACO provide a promising strategy for synthesis of epoxy resins with excellent flame retardancy, smoke suppression and flexible performance.

A magnesium alloy containing essential, non-toxic, biodegradable elements such as Ca and Zn has been fabricated using a novel twin-roll casting process (TRC). Microstructure, mechanical properties, in vivo corrosion and biocompatibility have been assessed and compared to the properties of the rare earth (RE) element containing WE43 alloy. TRC Mg-0.5 wt% Zn- 0.5 wt% Ca exhibited fine grains with an average grain size ranging from 70 to 150 μm. Mechanical properties of a TRC Mg-0.5Zn-0.5Ca alloy showed an ultimate tensile strength of 220 MPa and ductility of 9.3%. The TRC Mg-0.5Zn-0.5Ca alloy showed a degradation rate of 0.51 ± 0.07 mm/y similar to that of the WE43 alloy (0.47 ± 0.09 mm/y) in the rat model after 1 week of implantation. By week 4 the biodegradation rates of both alloys studied were lowered and stabilized with fewer gas pockets around the implant. The histological analysis shows that both WE43 and TRC Mg-0.5Zn-0.5Ca alloy triggered comparable tissue healing responses at respective times of implantation. The presence of more organized scarring tissue around the TRC Mg-0.5Zn-0.5Ca alloys suggests that the biodegradation of the RE-free alloy may be more conducive to the tissue proliferation and remodelling process., Graphical abstract Image 1, Highlights • Mg-0.5Zn-0.5Ca alloy plates were fabricated by a twin-roll casting (TRC) process. • TRC alloy showed an ultimate strength and elongation of 221 ± 2 MPa and 9 ± 2%. • Gas development during in vivo degradation was analysed using μ-CT techniques. • Histological analysis revealed a good biocompatibility and promoted healing.

Sustainable conversion of waste plastics into valuable carbon materials for diverse applications provides a promising strategy to dispose the municipal and industrial waste plastics. However, it remains a challenge to precisely control the crosslinking reaction for transforming waste polyesters into N-doped porous carbon (NPC) with well-defined microstructures. Herein, we put forwards a strategy of stepwise crosslinking using melamine and ZnCl2/NaCl eutectic salts to convert poly (ethylene terephthalate) (PET) into NPC at 550 °C. We prove that firstly melamine reacts with PET degradation products to form a crosslinking structure, and subsequently ZnCl2/NaCl promote the dehydration and decarboxylation of the crosslinking structure to generate a more thermally stable crosslinking structure. The coordination of two tandem crosslinking reactions is critical to control the microstructure of NPC. Without activations, NPC shows large specific surface area of 1173 m2 g−1, abundant N dopants, and rich oxygen-containing groups. These combined features endure NPC with excellent performance in CO2 capture and solar steam generation, e.g., high CO2 adsorption capacity of 6.47 mmol g−1 and evaporation rate of 1.62 kg m−2 h−1. More importantly, NPC is compared to or prevails over previous carbon-based CO2 adsorbents or photothermal materials. This work will advance the research on “green” reutilization of low-cost polyester wastes to prepare sustainable carbon for solar energy conversion, environmental protection, etc.

Electrospun biodegradable polymers have emerged as promising materials for their applications in several fields, including biomedicine and food industry. For this reason, the susceptibility of these materials to be colonized by different pathogens is a critical issue for public health, and their study can provide future knowledge to develop new strategies against bacterial infections. In this work, the ability of three pathogenic bacterial species (Pseudomonas aeruginosa, Acinetobacter baumannii, and Listeria monocytogenes) to adhere and form biofilm in electrospun polycaprolactone (PCL) microfibrous meshes was investigated. Bacterial attachment was analyzed in meshes with different microstructure, and comparisons with other materials (borosilicate glass and electrospun polylactic acid (PLA)) fibers were assessed. Analysis included colony forming unit (CFU) counts, scanning electron microscopy (SEM), and crystal violet (CV) staining. All the obtained data suggest that PCL meshes, regardless of their microstructure, are highly susceptible to be colonized by the pathogenic relevant bacteria used in this study, so a pretreatment or a functionalization with compounds that present some antimicrobial activity or antibiofilm properties is highly recommended before their application. Moreover, an experiment designed to simulate a chronic wound environment was used to demonstrate the ability of these meshes to detach biofilms from the substratum where they have developed, thus making them promising candidates to be used in wound cleaning and disinfection., European Union’s H2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no. 691095 and Junta de Castilla y Leon-FEDER (projects BU079U16 and BU092U16).

A relation for an adequate pore fraction needed to obtain residual Si and C free composites via reactive Si-X alloy infiltration is presented. The volume ratio of SiC and carbonaceous phase, the composition of the infiltrating liquid and the apparent density of the preform are used as design entities. The approach allows identifying combinations of these design entities leading to desirable microstructures, e.g. those free of residual silicon or free of excess graphite. The approach gives further access to important post infiltration characteristics like propensity of the various phases. An idealising mathematical model describing the reactive flow of Si-X alloy in a single micron sized capillary channel of carbon as well as in carbonaceous preforms is presented. The model is further expanded to evaluate the infiltration depth in porous carbonaceous preform for a given composition of Si-X alloy and infiltration temperature. The model is presented for both isothermal and non-isothermal cases. The analysis is formulated in general terms and is hence applicable to a large variety of Si-C-refractory metal systems of potential interest.

A composite coating of nitrogen-doped carbon dots (N CDs) and polydopamine (PDA) was prepared on magnesium alloy by combining electrodeposition with dip coating methods. The microstructure of the N CDs/PDA composite coating, including composition, surface morphology, and crystalline structure, is characterized by Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy, respectively. The corrosion protection performances of the composite coating are evaluated by potentiodynamic polarization tests, electrochemical impedance spectroscopy, and salt spray tests. The effect of the particle size of the N CDs on the corrosion performance is also investigated. The results show that the corrosion performance of the N CDs coatings are enhanced with the increase of the particle sizes. Furthermore, an obvious self-healing performance is observed on the surface of the N CDs/PDA composite coating. These results indicate that N CDs/PDA composite coating can improve the corrosion performance of the Mg alloy, and open a new design direction for the protective coating of metallic materials.

In this work, we investigated leaching of lanthanide and yttrium (REY) from a Central Appalachian coal and its ashes obtained at 550–950 °C with the main purpose of understanding the impact of ashing temperature on REY leachability in water, ammonium sulfate, and hydrochloric acid. It is found that the coal contains a negligible amount of water-soluble REY, less than 1% ion-exchangeable REY, and about 28% of HCl-soluble REY. Ashing leads to dramatic changes in REY leachability in both ammonium sulfate and hydrochloric acid solutions, which is believed to be related to transformation and redistribution of organically-associated REY in coal during the ashing process. Ashing temperature significantly affects REY leaching from coal ashes; higher ashing temperature results in lower REY leachability in both solutions. Clay minerals may play a significant role in changing the leachability of REY after ashing. In addition, the results also suggest that the organic matter in the coal is relatively enriched in heavy REY.

This work produced a MgAl-layered double hydroxide by hydrothermal treatment of a plasma electrolytic oxidation (PEO) coating on magnesium alloy AZ31 in an phosphate electrolyte, followed by an ion-exchange reaction in 0.1 M phosphate solution. The coated specimens were scratched. Characterization, including utilization of the localized technique SIET, measured the pH and pMg distributions and optical morphologies around the artificial defects during immersion in 0.05 M NaCl solution. In contrast with phosphate loaded PEO/LDHs, a stronger alkalinization area (with pH 11.4∼12.3) appeared in the passive PEO specimens. Due to formation of insoluble Mg(OH)2 products, the pMg map showed depletion of Mg2+ in this high pH area. Combined with optical morphologies and SEM images, the better self-healing ability toward defects for phosphate loaded PEO/LDHs was confirmed.

The strength and durability of structures are strongly influenced by damage from steel corrosion caused by chloride ions. This chloride-induced corrosion mechanism is investigated yearly. However, the strength and durability of steel fibre recycled concrete (SFRC) in chloride environments have rarely been studied. By changing the water–cement ratio of SFRC blocks, the sodium chloride (NaCl) concentration of the soaking solution, soaking time and the number of chloride-ion-permeating surfaces, a series of compressive strength experiments were performed, where the chloride ion content of tested blocks was measured. The results showed that the water–cement ratio of blocks greatly influences the strength and durability of SFRC and that the sodium chloride concentration of the soak solution, and the number of chloride-ion-permeating surfaces, also affects the blocks to a certain degree. A water–cement ratio of 0·45 should be chosen due to its low chloride ion content and high compressive strength. The water–cement ratio and the number of chloride-ion-permeating surfaces can be controlled more easily in practical engineering, it is therefore necessary to optimise the best water–cement design ratio and add a water-repellent coating on the SFRC surfaces to ensure the durability of the structure.

Titanium alloys have a wide application in aerospace industries as it has greater strength and low density, but it has poor tribological properties. To improve its friction and wear performance, in present work, a femtosecond laser is used to directly irradiate the Ti6Al4V titanium alloy surface in air conditioning, which results in localized ablation and the formation of periodic microstructures but also a strong pressure wave, propagating the material inside. Through the optimization of processing parameters, surface modification and periodic micropatterning with effective anti-friction properties were successfully induced on the surface. After a treatment of femtosecond laser-induced surface modification (FsLSM), the surface microhardness was improved by 16.6% and compressive residual stress reached −746 MPa. Besides, laser-induced periodic surface structures (LIPSS) with a titanium oxide outer coating were fabricated uniformly on the titanium alloy surface. Rotary ball-on-disk wear experiments revealed that the average coefficient of friction (COF) and wear mass loss of the specimen with FsLSM treatment were largely reduced by 68.9% and 90% as compared to that of untreated specimens, respectively. It was analyzed that the reason for the remarkable wear resistance was attributed to the comprehensive action of the generation of LIPSS, the titanium oxide outer coating, high amplitude compressive residual stress and gradient grain size distribution on the subsurface during the laser surface treatment. Since the findings here are broadly applicable to a wide spectrum of engineering metals and alloys, the present results offer unique pathways to enhancing the tribological performance of materials.

In the present study, composites of Polyaniline and some fruit peels were synthesized in various conditions and used for lead removal from aqueous solutions. Adsorption tests were conducted in batch mode using the most efficient adsorbent, and the effects of medium pH, initial lead concentration, contact time, adsorbent dosage, and adsorption isotherms were investigated. The results showed that all composites were more efficient in lead removal compared to the fruit peels alone. The highest removal percentage was related to the composite of banana peel and Polyaniline that synthesized in the aqueous solution in the presence of 2 g·L−1 Poly ethylene glycol. This composite showed 95.96% lead adsorption at pH=6, the contact time of 90 min, the initial lead concentration of 25 mg·L−1, and an adsorbent concentration of 8 g·L−1. Adsorption isotherm study showed that adsorption of lead by synthesized composite could be fitted by both Langmuir and Freundlich models, but the Langmuir model was more fitted than Freundlich. Besides, some characteristics of the composites, such as chemical composition (XRD analysis), structure, and morphology (SEM analysis) and functional groups (FTIR analysis), were studied.

This study tested whether osseous integration into poly (ε-caprolactone) (PCL) bioplastic scaffolds with fully-interconnecting 155 ± 8 μm pores is enhanced by an adhesive, non-inflammatory 99% degree of deacetylation (DDA) chitosan coating (99-PCL), or further incorporation of pro-inflammatory 83% DDA chitosan microparticles (83-99-PCL) to accelerate angiogenesis. New Zealand White rabbit osteochondral knee defects were press-fit with PCL, 99-PCL, 83-99-PCL, or allowed to bleed (drill-only). Between day 1 and 6 weeks of repair, drill-only defects repaired by endochondral ossification, with an 8-fold higher bone volume fraction (BVF) versus initial defects, compared to a 2-fold (99-PCL), 1.1-fold (PCL), or 0.4-fold (83-99-PCL) change in BVF. Hematoma innate immune cells swarmed to 83-99-PCL, elicited angiogenesis throughout the pores and induced slight bone resorption. PCL and 99-PCL pores were variably filled with cartilage or avascular mesenchyme near the bone plate, or angiogenic mesenchyme into which repairing trabecular bone infiltrated up to 1 mm deep. More repair cartilage covered the 99-PCL scaffold (65%) than PCL (18%) or 83-99-PCL (0%) (p < 0.005). We report the novel finding that non-inflammatory chitosan coatings promoted cartilage infiltration into and over a bioplastic scaffold, and were compatible with trabecular bone integration. This study also revealed that in vitro osteogenesis assays have limited ability to predict osseous integration into porous scaffolds, because (1) in vivo, woven bone integrates from the leading edge of regenerating trabecular bone and not from mesenchymal cells adhering to scaffold surfaces, and (2) bioactive coatings that attract inflammatory cells induce bone resorption., Graphical abstract Image 1, Highlights • Porous polycaprolactone scaffolds elicited drawn-out osteochondral wound repair. • Regenerating trabecular bone only infiltrated angiogenic mesenchyme free of inflammatory cells. • 83% DDA chitosan stimulated sterile inflammatory angiogenesis and trabecular bone resorption. • 99% DDA chitosan coatings promoted chondrogenesis inside and over the PCL articular surface.

Carbon dots (CDs) have attracted more interest in tumor theranostics, but they suffer from the rapid renal clearance due to small size and high hydrophilicity. To solve such problems, hydrophobic pH-triggered carbon dot-drug conjugate (CDs-Hy-DOX) with high doxorubicin (DOX) content of 48.23% were designed by covalent conjugation of DOX onto the CDs via acid-labile linkage with hydrazine (Hy) as bridge. Then the fluorescent traceable hybrid prodrug nanoparticles were fabricated via co-self-assembly with the CDs-Hy-DOX as pH-sensitive prodrug and a pH/reduction dual-triggered degradable hyperbranched polymer PEG-PO-Cy as polyethylene glycol (PEG)-based surfactant, as well as gatekeeper for pH/reduction dual-triggered DOX release. The hybrid prodrug nanoparticles with hydrodynamic diameter of 220 nm and DOX content of 22.99% were obtained with the optimized co-self-assembling condition. They could release 68.98% of DOX in the simulated tumor microenvironment within 3 days in a sustained release mode, with a premature drug leakage of 7.58%. After the acid-triggered DOX release from the CDs-Hy-DOX, which was accelerated by the pH/reduction dual-triggered degradation of the hyperbranched polymer, the strong fluorescence of CDs-Hy was recovered, demonstrating the promising potential in future tumor nanotheranostics.

Supramolecular nanofiber peptide assemblies had been used to construct functional hydrogel biomaterials and achieved great progress. Here, a new class of biphenyl-tripeptides with different C-terminal amino acids sequences transposition were developed, which could self-assemble to form robust supramolecular nanofiber hydrogels from 0.7 to 13.8 kPa at ultra-low weight percent (about 0.27 wt%). Using molecular dynamics simulations to interrogate the physicochemical properties of designed biphenyl-tripeptide sequences in atomic detail, reasonable hydrogen bond interactions and “FF” brick (phenylalanine-phenylalanine) promoted the formation of supramolecular fibrous hydrogels. The biomechanical properties and intermolecular interactions were also analyzed by rheology and spectroscopy analysis to optimize amino acid sequence. Enhanced L929 cells adhesion and proliferation demonstrated good biocompatibility of the hydrogels. The storage modulus of BPAA-AFF with 10 nm nanofibers self-assembling was around 13.8 kPa, and the morphology was similar to natural extracellular matrix. These supramolecular nanofiber hydrogels could effectively support chondrocytes spreading and proliferation, and specifically enhance chondrogenic related genes expression and chondrogenic matrix secretion. Such biomimetic supramolecular short peptide biomaterials hold great potential in regenerative medicine as promising innovative matrices because of their simple and regular molecular structure and excellent biological performance., Graphical abstract Supramolecular nanofiber short peptide hydrogels with primary amino acid sequences transposition have ultra-low critical gelation concentration and excellent mechanical properties, and effectively support the chondrocytes spreading and proliferation and specifically enhance chondrogenic marker genes expression and chondrogenic matrix secretion.Image 1, Highlights • PH-triggered biphenyl-tripeptide nanofiber supramolecular hydrogels were engineered. • Molecular dynamics simulation was integrated into experimental approach to optimize structure. • The nanofiber supramolecular hydrogels with 0.7–13.8 kPa were achieved at only 0.27 wt%. • The BPAA-AFF enhanced chondrogenic related genes expression and matrix secretion.

The properties of coatings formed on the MA8 magnesium alloy by the plasma electrolytic oxidation in electrolytes containing mechanical mixture of zirconia and silica nanoparticles in concentrations of 2, 4 and 6 g/l have been investigated. It has been established by SEM, EDS, and XPS that ZrO2/SiO2 nanoparticles successfully were incorporated into the coatings. Micro-Raman spectroscopy showed the presence of ZrO2 in tetragonal and monoclinic forms in the PEO-coating composition as well as Mg2SiO4 in tetrahedral configuration uniformly distributed in the outer part of coatings. Obtained coatings significantly reduce corrosion current density in comparison with bare Mg alloy and base PEO-layer (from 2.4 × 10–7 A/cm2 for base PEO layer to 0.7 × 10–7 A/cm2 for coatings with nanoparticles). It has been found that the presence of solid nanoparticles in the composition of coating has a positive effect on their hardness (this parameter was increased from 2.1 ± 0.3 GPa to 3.1 ± 0.4 GPa) and wearproof (the wear was reduced from (4.3 ± 0.4)×10–5 mm3/(N × m) to (3.5 ± 0.2)×10–5 mm3/(N × m)).

This paper examines the hydration behaviour of polymer enhanced geosynthetic clay liners (GCLs) under both isothermal conditions and diurnal cyclical temperatures as recorded at a Melbourne landfill site. The diurnal temperature cycles introduced thermal gradients, which induced water movement downwards into the subgrade. It was found that the bulk of the thermal and hydraulic effects occurred within the upper 50 mm of the subgrade layer. Compared to isothermal conditions, diurnal temperature cycling's main effect was to suppress GCL hydration. Thermal gradients induced capillary breaks, and GCL hydration was thus limited to vapour phase hydration from the subgrade, which restricted the gravimetric water content of the GCLs to

Hypothesis Lung surfactant protects lung tissue and reduces the surface tension in the alveoli during respiration. Particulate matter with an aerodynamic diameter of less than 2.5 μm (PM2.5), which invades primely through inhalation, can deposit on and interact with the surfactant layer, leading to changes in the biophysical and morphological properties of the lung surfactant. Experiments Langmuir monolayers of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) and clinical surfactant Calsurf were investigated with a PM2.5 model injected into the water subphase, which were characterized by surface pressure-area isotherms, Brewster angle microscopy, atomic force microscopy, fluorescent microscopy, and x-ray photoelectron spectroscopy. The binding between DPPC/Calsurf and PM2.5 was studied using isothermal titration calorimetry. Findings PM2.5 induced the expansion of the monolayers at low surface pressure (п) and film condensation at high п. Aggregation of PM2.5 mainly occurred at the interface of liquid expanded/liquid condensed (LE/LC) phases. PM2.5 led to slimmer and ramified LC domains on DPPC and the reduction of nano-sized condensed domains on Calsurf. Both DPPC and Calsurf showed fast binding with PM2.5 through complex binding modes attributed to the heterogeneity and amphiphilic property of PM2.5. This study improves the fundamental understanding of PM2.5-lung surfactant interaction and shows useful implications of the toxicity of PM2.5 through respiration process.

Bone defects caused by infection, tumor, trauma and so on remain difficult to treat clinically. Bone tissue engineering (BTE) has great application prospect in promoting bone defect repair. Polycaprolactone (PCL) is a commonly used material for creating BTE scaffolds. In addition, self-assembling peptides (SAPs) can function as the extracellular matrix and promote osteogenesis and angiogenesis. In the work, a PCL scaffold was constructed by 3D printing, then integrated with bone marrow mesenchymal stem cells (BMSCs) and SAPs. The research aimed to assess the bone repair ability of PCL/BMSC/SAP implants. BMSC proliferation in PCL/SAP scaffolds was assessed via Cell Counting Kit-8. In vitro osteogenesis of BMSCs cultured in PCL/SAP scaffolds was assessed by alkaline phosphatase staining and activity assays. Enzyme linked immunosorbent assays were also performed to detect the levels of osteogenic factors. The effects of BMSC-conditioned medium from 3D culture systems on the migration and angiogenesis of human umbilical vein endothelial cells (HUVECs) were assessed by scratch, transwell, and tube formation assays. After 8 weeks of in vivo transplantation, radiography and histology were used to evaluate bone regeneration, and immunohistochemistry staining was utilized to detect neovascularization. In vitro results demonstrated that PCL/SAP scaffolds promoted BMSC proliferation and osteogenesis compared to PCL scaffolds, and the PCL/BMSC/SAP conditional medium (CM) enhanced HUVEC migration and angiogenesis compared to the PCL/BMSC CM. In vivo results showed that, compared to the blank control, PCL, and PCL/BMSC groups, the PCL/BMSC/SAP group had significantly increased bone and blood vessel formation. Thus, the combination of BMSC-seeded 3D-printed PCL and SAPs can be an effective approach for treating bone defects.

Due to the great fouling resistance property, (super)hydrophilic/underwater superoleophobic membranes are prevalent candidates for oil-polluted wastewater treatment. Even so, membrane fouling inevitably occurs during long-term operation. Therefore, it is of great significance to construct anti-fouling membranes with robust flux recovery. Herein, a polyvinyl pyrrolidone (PVP) coated porous potassium-doped g-C3N4 (PKCN) membrane was fabricated for the first time by vacuum filtration. The as-prepared membrane displays enhanced hydrophilicity and underwater superoleophobicity. The permeability of the membrane increased significantly after sonication treatment, which is attributed to the increased pore volume and small nanosheets size that shorten the transport pathway of water molecules. Importantly, owing to the high photo-Fenton activity, the PKCN membrane exhibits fast (within 15 min) and excellent flux recovery (96.5%) after the photo-Fenton cleaning process. Furthermore, after 10 repeated usages, the PKCN membrane still keeps stable permeability and excellent purification efficiency. This work opens a door for developing self-cleaning membranes with the superior anti-fouling ability for effective oil/water separation.

We demonstrate a simple, effective and feasible method to address the shrinkage of Poly (lactic-co-glycolic acid) (PLGA) through a core-shell structure fiber strategy. The results revealed that introducing size-stable poly-caprolactone (PCL) as the core fiber significantly improved the PLGA-based fibrous scaffold's dimensional maintenance. We further utilized fish collagen to modify the PLGA shell layer (PFC) of coaxial fibers and loaded baicalin (BA) into the PCL core layer (PCL-BA) to endow fibrous scaffold with more functional biological cues. The PFC/PCL-BA fibrous scaffold promoted the osteogenic differentiation of bone mesenchymal stem cells and stimulated the RAW264.7 cells to polarize into a pro-reparative phenotype. Importantly, the in vivo study demonstrated that the PFC/PCL-BA scaffold could regulate inflammation and osteoclast differentiation, favor neovascularization and bone formation. This work tactfully combined PLGA and PCL to establish a drug release platform based on the core-shell fibrous scaffold for vascularized bone regeneration., Graphical abstract A multifunctional baicalin-loaded coaxial nanofiber scaffold prepared by electrospinning technology, which can effectively resist the shrinkage of PLGA, alleviate the inflammatory response after implantation, and more importantly, can achieve vascularized bone regeneration. This is a simple and feasible strategy for bone tissue regeneration, and the PFC/PCL-BA scaffold is expected to be an alternative for bone grafts.Image 1, Highlights • A multifunctional baicalin-loaded coaxial fiber scaffold prepared by electrospinning. • The coaxial nanofiber can effectively resist the shrinkage of PLGA. • Baicalin endow the nanofibrous scaffold with excellent biological properties. • The scaffold can alleviate the inflammation and achieve vascularized bone regeneration.

Preparation of bismuth oxybromide (BiOBr) photocatalyst via PVP-assisted solvothermal method has been demonstrated. The PVP capping agent plays an important role in controlling morphological structure, specific surface area and photoactivity. The PVP capped BiOBr provides 94 % and 99.8 % removal of ofloxacin (OFL) and norfloxacin (NOR) antibiotics under visible light illumination. The enhanced photoactivity of the PVP capped BiOBr is due to the flower-like microstructures with high surface area and the suppression of electron-hole pairs recombination at the interfaces. Photogenerated hole and electron play the key role in degradation of the antibiotics. The photocatalyst retains its efficiency after the fifth run indicating structural stability and reusability. The prepared PVP capped BiOBr photocatalyst shows high potential for environmental protection. The present finding offers a new avenue for fabrication of the visible-light-responsive catalyst for detoxification of antibiotics in wastewater.

With the increasing prevalence of drug-resistant bacterial infections and the slow healing of chronically infected wounds, the development of new antibacterial and accelerated wound healing dressings has become a serious challenge. In order to solve this problem, we developed photo-crosslinked multifunctional antibacterial adhesive anti-oxidant hemostatic hydrogel dressings based on polyethylene glycol monomethyl ether modified glycidyl methacrylate functionalized chitosan (CSG-PEG), methacrylamide dopamine (DMA) and zinc ion for disinfection of drug-resistant bacteria and promoting wound healing. The mechanical properties, rheological properties and morphology of hydrogels were characterized, and the biocompatibility of these hydrogels was studied through cell compatibility and blood compatibility tests. These hydrogels were tested for the in vitro blood-clotting ability of whole blood and showed good hemostatic ability in the mouse liver hemorrhage model and the mouse-tail amputation model. In addition, it has been confirmed that the multifunctional hydrogels have good inherent antibacterial properties against Methicillin-resistant Staphylococcus aureus (MRSA). In the full-thickness skin defect model infected with MRSA, the wound closure ratio, thickness of granulation tissue, number of collagen deposition, regeneration of blood vessels and hair follicles were measured. The inflammation-related cytokines (CD68) and angiogenesis-related cytokines (CD31) expressed during skin regeneration were studied. All results indicate that these multifunctional antibacterial adhesive hemostatic hydrogels have better healing effects than commercially available Tegaderm™ Film, revealing that they have become promising alternative in the healing of infected wounds., Graphical abstract Image 1, Highlights • Antibacterial antioxidant adhesion hydrogel was obtained by photopolymerization. • These hydrogels exhibited good hemostatic property and cell compatibility. • The hydrogels showed good antibacterial property against MRSA. • The hydrogels significantly enhanced wound healing of infected skin wound.

Lignin is a versatile biomass that possesses many different desirable properties such as antioxidant, antibacterial, anti-UV, and good biocompatibility. Natural lignin can be processed through several chemical processes. The processed lignin can be modified into functionalized lignin through chemical modifications to develop and enhance biomaterials. Thus, lignin is one of the prime candidate for various biomaterial applications such as drug and gene delivery, biosensors, bioimaging, 3D printing, tissue engineering, and dietary supplement additive. This review presents the potential of developing and utilizing lignin in the outlook of new and sustainable biomaterials. Thereafter, we also discuss on the challenges and outlook of utilizing lignin as a biomaterial., Graphical abstract Image 1, Highlights • Lignin's antioxidant, antibacterial, anti-UV and biocompatibility properties can be harnessed. • Modification and functionalization of lignin allows synthesis of enhanced biomaterials. • Biomedical applications of lignin-derived biomaterials include drug and gene delivery, biosensors, and tissue engineering.

The combination of tumor ablation and immunotherapy is a promising strategy against tumor relapse and metastasis. Photothermal therapy (PTT) triggers the release of tumor-specific antigens and damage associated molecular patterns (DAMPs) in-situ. However, the immunosuppressive tumor microenvironment restrains the activity of the effector immune cells. Therefore, systematic immunomodulation is critical to stimulate the tumor microenvironment and augment the anti-tumor therapeutic effect. To this end, polyethylene glycol (PEG)-stabilized platinum (Pt) nanoparticles (Pt NPs) conjugated with a PD-L1 inhibitor (BMS-1) through a thermo-sensitive linkage were constructed. Upon near-infrared (NIR) exposure, BMS-1 was released and maleimide (Mal) was exposed on the surface of Pt NPs, which captured the antigens released from the ablated tumor cells, resulting in the enhanced antigen internalization and presentation. In addition, the Pt NPs acted as immune adjuvants by stimulating dendritic cells (DCs) maturation. Furthermore, BMS-1 relieved T cell exhaustion and induced the infiltration of effector T cells into the tumor tissues. Thus, Pt NPs can ablate tumors through PTT, and augment the anti-tumor immune response through enhanced antigen presentation and T cells infiltration, thereby preventing tumor relapse and metastasis.

Humans are continuously plagued by number of new uncured diseases, resulting in the search of new medicines with zero level side effects. In the present study, an attempt has been made to prepare, characterize and to test the wound healing activity of chitosan based hydrogel. Shrimp shells was collected from Cuddalore (Lat 11° 42 N Long 79° 46 E), Annankovil (Lat. 11°30.47 N; Long. 079°47. 02E) and Mudasalodai landing centre (11o29 ′N 79o46 ′E) (Southeast coast of India) for extraction of chitin and chitosan and further characterized by FTIR, 1H – NMR, DSC, SEM and XRD. Poly Ethylene Glycol (PEG) is used as a cross linking agent for the preparation of chitosan hydrogel. The prepared hydrogel was characterized by FTIR, SEM, DSC and its swelling property was tested. Synthesized chitosan hydrogel was shown very good level of growth inhibition activity against human pathogens and wound healing activity within 12 h to 24 h. Thus the present study suggests the possibility of utilizing seafood waste of crustacean shells for the extraction and preparation of useful biologically active compounds like hydrogel for medicinal drug delivery and therapeutic applications.

Droplet-based microfluidics is an emerging field that has found its way in different applications like material science and biotechnology. Knowing how factors like capillary number, surface tension, velocity ratio, viscosity ratio, and contact angle affect droplet formation is of upmost importance for the design of microfluidic platforms. In this study, we evaluate how these factors affect droplet formation by using the two-phase level set method, measuring its length and frequency. Additionally, to assess how channel geometry affects droplet length and frequency, we considered the three most commonly used flow-focusing geometries in microfluidic platforms. As a general conclusion, we found that the droplet length decreases when the capillary number, velocity ratio, and viscosity ratio increase, while it increases when surface tension increases as well. The frequency of droplet formation augments when the capillary number, velocity ratio, and viscosity ratio increase, while it decreases when surface tension increases. We found that geometry influences droplet length, while it has minor effects on droplet formation frequency. Moreover, the contact angle has a low effect on both droplet length and formation frequency in flow focusing devices compared to other studies carried out using different geometries like the T-junction.

Modulating the activation state and degree of macrophages still remains as a challenge for the topographical design of Ti-based implants. In this work, micro/nano-structured coatings were prepared on Ti substrates by micro-arc oxidation (MAO) and subsequent hydrothermal (HT) treatment. By varying the HT conditions, plate-like nano-structures with an average length of 80, 440 or 780 nm were obtained on MAO-prepared micro-topographical surfaces. Depending on the dimensional features of nano-plates, the specimens were noted as Micro, Micro/Nano-180, Micro/Nano-440 and Micro/Nano-780, respectively. The in vitro results showed that the activation state and degree of macrophages could be effectively modulated by the micro/nano-structured surfaces with various dimensional features. Compared to the Micro surface, the Micro/Nano-180 surface activated both M1 and M2 phenotype in macrophages, while the Micro/Nano-440 and Micro/Nano-780 surfaces polarized macrophages to their M1 phenotype. The activation degree of M1 macrophages followed the trend: Micro

To assess the radiological properties of racemosa wooden dust (RWD) and Poly (methyl methacrylate) (PMMA) for design and fabrication of a thoracic phantom for radiation dose verification in mega-voltage X-ray beam. The computed tomography images of RWD and PMMA were used to determine the radiological properties viz., Hounsfield units (HUs), relative electron density (RED) and mass density (MD). The estimated HUs, RED and MD were −828.2 ± 11.9, 0.172 ± 0.012, 0.150 ± 0.012 g/cc and 108.5 ± 7.3, 1.104 ± 0.004, 1.088 ± 0.005 g/cc for RWD and PMMA, respectively. The radiological properties of RWD and PMMA were in congruence with the value detailed in literature for lung tissue and muscle tissue of human body. Therefore, a phantom was design and fabricated using the combination of RWD and PMMA for radiation dose verification prior to radiation delivery to the cancer patients. The average deviation between dose computation engine and Ion-chamber estimations were within the stipulated tolerance (±3%). Thus, it was culminated that RWD and PMMA can be utilized for design and fabrication of phantom, which vindicates precise information about the quality assurance program for thoracic cancer patient treated using mega-voltage X-ray beam.

International audience; In this study coatings of kaolin and talc particles were successfully applied on the surface of polyamide 12 powder intended for laser sintering (LS). Microscopic observations revealed that using carboxymethyl cellulose (CMC) as surface modifier for fillers led to a better coverage of polymer grains with a surface coverage between 6 and 16% as a function of filler type and content. Differential scanning calorimetry measurements showed that the addition of talc and kaolin led to an increase in the crystallization temperature of PA12, but at the expense of processability. Process parameters were optimized in order to manufacture LS samples with the different coated powders. Fire behavior assessed by cone calorimetry showed that the use of CMC resulted in a significant decrease in the peak of heat release rate depending on the filler type and content. This behavior can be partially explained by an interaction between CMC, fillers and polymer, with the formation of amide linkage between carboxyl part of CMC and amine end groups of polyamide, resulting in an increase in the complex viscosity of materials.

A napthofluoresciene based NIR fluorescent probe for sulfide was synthesized and characterized by nmr and ESI-MS spectrometry. The present probe can act as rapid, colorimetric and NIR fluorescent turn on sulfide sensor at nano molar levels. It is highly selective to sulfide over other reducing agents like sulfate, sulfite and also thiol moieties. It has been successfully applied for the determination of sulfide in various environmental water samples.

Magnesium (Mg) and its alloys have emerged as a favored candidate for bio-regenerative medical implants due to their superior biocompatibility, biodegradability and the elastic modulus close to that of human bone. Unfortunately, the rapid and uncontrollable degradation rate of Mg alloys in chloride-rich body microenvironments limits their clinical orthopedic applications. Recently, Calcium Phosphate (Ca-P) biomaterials, especially Hydroxyapatite (HA), have been broadly applied in the surface functional modification of metal-based biomaterials attributed to their excellent bioactivity and biocompatibility. Hydrothermal modification of Ca-P coatings on Mg alloys has been extensively exploited by researchers for its significant superiorities in controlling coating structure and improving interfacial bonding strength for better osseointegration and corrosion resistance. This work focuses on the up-to-the-minute advances in Ca-P coatings on the surface of Mg and its alloys via hydrothermal methods, including the strategies and mechanisms of hydrothermal modification. Herein, we are inclined to share some feasible and attractive hydrothermal surface modification strategies. From the perspectives of hydrothermal manufacturing technique innovation and coating structure optimization, we evaluate how to foster the corrosion resistance, coating bonding strength, osseointegration and antibacterial properties of Mg alloys with Ca-P coatings synthesized by hydrothermal method. The challenges and future perspectives on the follow-up exploration of Mg alloys for orthopedic applications are also elaborately proposed.

Hexavalent chromium [Cr(VI)] is a heavy metal pollutant in the environment released through leather tanning. In this context, the present study was envisaged to isolate and identify chromium reducing bacteria in order to employ them towards detoxification of chromium. In general, bacteria are ecofriendly and cost-effective which can be efficiently used in bioremediation processes. The collected tannery effluents yielded considerable Bacillus species. These isolates demonstrated well for their resistance which showed exceptional Cr(VI) reduction within 48 h under aerobic conditions. Mostly, chromium resistance confers through Chromate transporters which involves metabolic reduction of toxic Cr(VI) to non-toxic Cr(III). Distribution of chr genes in Bacillus species were identified from their genome through UniProt. Treatment of raw tannery effluent employing these isolates individually or as a consortia reduced Cr(VI) significantly. Thus, these bacterial strains, could evolve as a potential organisms to reduce toxic Cr(VI) to its non-toxic Cr(III) form in chromium contaminated sites.

Bone regeneration is a crucial part in the treatment of periodontal tissue regeneration, in which new attempts come out along with the development of nanomaterials. Herein, the effect of cerium oxide nanoparticles (CeO2 NPs) on the cell behavior and function of human periodontal ligament stem cells (hPDLSCs) was investigated. Results of CCK-8 and cell cycle tests demonstrated that CeO2 NPs not only had good biocompatibility, but also promoted cell proliferation. Furthermore, the levels of alkaline phosphatase activity, mineralized nodule formation and expressions of osteogenic genes and proteins demonstrated CeO2 NPs could promote osteogenesis differentiation of hPDLSCs. Then we chose electrospinning to fabricate fibrous membranes containing CeO2 NPs. We showed that the composite membranes improved mechanical properties as well as realized release of CeO2 NPs. We then applied the composite membranes to in vivo study in rat cranial defect models. Micro-CT and histopathological evaluations revealed that nanofibrous membranes with CeO2 NPs further accelerated new bone formation. Those exciting results demonstrated that CeO2 NPs and porous membrane contributed to osteogenic ability, and CeO2 NPs contained electrospun membrane may be a promising candidate material for periodontal bone regeneration., Graphical abstract Schematic illustration of the in vitro and in vivo study of CeO2 NPs' effects on accelerating bone regeneration.Image 1, Highlights • CeO2 nanoparticles are induced in the therapy of periodontal regeneration as a bio-activator. • CeO2 nanoparticles have potential promotion on osteogenic differentiation of periodontal stem cells. • Fibrous membrane containing CeO2 nanoparticles was fabricated by electrospinning with biodegradable materials. • Incorporation CeO2 nanoparticles with PCL/gelatin enhance bone regeneration in rat critical bone defect.

Two-fluid atomization of highly viscous and shear thinning non-Newtonian fluids must overcome the viscous resistance. Conventional air-blast atomizers address this requirement by operating at highe...

Nano composites of conducting polyaniline with ZnS nanoparticles (PANI/ZnS) have been synthesized by in-situ polymerization of aniline monomer using ammonium persulphate as oxidizing agent. The formation of PANI/ZnS composites was assessed by UV–Vis spectroscopy, Transmission Electron Microscopy (TEM), Fourier Transform Infra-Red Spectroscope (FTIR), Atomic Force Microscope (AFM), Scanning Electron Microscope (SEM) and X ray diffraction analysis (XRD). FTIR and UV studies provided the information of functional group and optical behavior respectively SEM studies shows the well dispersion of ZnS Nanoparticles in the polyaniline matrix. Size determination identified and confirmed by TEM analysis.

In this work, we propose and demonstrate a carbon nanotube (CNT) field-effect transistor (FET) based biosensor for selective detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). CNT FETs were fabricated on a flexible Kapton substrate and the sensor was fabricated by immobilizing the reverse sequence of the 25-base portion of the RNA-dependent RNA polymerase gene of the SARS-CoV-2 onto the CNT channel. The biosensors were tested for the synthetic positive and control target sequences. The biosensor showed a selective sensing response to the positive target sequence with a limit of detection of 10 fM. The promising results from our study suggest that the CNT FET based biosensors can be used as a diagnostic tool for the detection of SARS-CoV-2.

Titanium and its alloys have become the ultimate choice for the next era of orthopedic implants such as Hip stem, acetabular cup, and orthopedic accessories. This critical review presents the challenges in fabrication and solutions (surface engineering) to successfully implement Ti alloys in biomedical industries successfully. A critical review on the application surface modification of Ti-alloy using thermal spray coatings has been reported. Hydroxyapatite (HA) has been used as vital biological coating-materials for load-bearing implant applications, mostly hip implants. Moreover, the research papers also present bibliometric analysis that reveals the researcher's information and their affiliation for significant contribution in the area of Ha-coatings on Ti-alloy using plasma spray techniques.

New viral infections, due to their rapid spread, lack of effective antiviral drugs and vaccines, kill millions of people every year. The global pandemic SARS-CoV-2 in 2019–2021 has shown that new strains of viruses can widespread very quickly, causing disease and death, with significant socio-economic consequences. Therefore, the search for new methods of combating different pathogenic viruses is an urgent task, and strategies based on nanoparticles are of significant interest. This work demonstrates the antiviral adsorption (virucidal) efficacy of nanoparticles of porous silicon (PSi NPs) against various enveloped and non-enveloped pathogenic human viruses, such as Influenza A virus, Poliovirus, Human immunodeficiency virus, West Nile virus, and Hepatitis virus. PSi NPs sized 60 nm with the average pore diameter of 2 nm and specific surface area of 200 m2/g were obtained by ball-milling of electrochemically-etched microporous silicon films. After interaction with PSi NPs, a strong suppression of the infectious activity of the virus-contaminated fluid was observed, which was manifested in a decrease in the infectious titer of all studied types of viruses by approximately 104 times, and corresponded to an inactivation of 99.99% viruses in vitro. This sorption capacity of PSi NPs is possible due to their microporous structure and huge specific surface area, which ensures efficient capture of virions, as confirmed by ELISA analysis, dynamic light scattering measurements and transmission electron microscopy images. The results obtained indicate the great potential of using PSi NPs as universal viral sorbents and disinfectants for the detection and treatment of viral diseases., Graphical abstract Image 1

In this paper, we have used solution cast technique to synthesize ionic liquid incorporated PEO (Poly(ethylene oxide) with KI (Potassium Iodide) doped polymer electrolyte. The ionic conductivity enhances rapidly after adding ionic liquid in polymer salt complex and reaches 4.2*10−4 S/cm. Characterization such as Fourier transform infrared spectroscopy (FTIR) and polarized optical microscopy (POM) was also done to check the blending nature and amorphousity of the developed polymer electrolyte. Finally, the supercapacitor has been developed using high conducting ionic liquid (IL) doped polymer electrolyte which shows the specific capacitance 12.28F/g at 5 mV/s.

In this work, we have investigated the optical and electrical properties of pyrrole-2-carboxyldehyde (PCL) dispersed in sodium dodecyl sulphate (SDS) micellar system and frezeed in polyvinyl alcohol (PVA) polymer matrix. PVA polymer is chosen as hosting materials in the composite fabrication due to its vast applicability. The optical properties have been studied with the help of different spectroscopic techniques. The optical and electrical properties of trapped PCL were observed to be highly detectable even in solid form freezed in a polymer matrix. Our study shows that PCL in solid phase may be considered as the promising candidates for bio medical applications.