Synthesis Parameters Research Articles

Microfluidic-assisted sol-gel preparation of monodisperse mesoporous silica microspheres with controlled size, surface morphology, porosity and stiffness.

The controllable synthesis of monodisperse mesoporous silica microspheres with unique physicochemical properties is becoming increasingly important for a variety of applications such as catalysts, chromatography, drug delivery and sensors. Here, we report a facile microfluidic-assisted sol-gel method for the preparation of silica microspheres with precisely controlled properties such as the size of the microspheres, the surface morphology, porosity and stiffness. All these properties can be manipulated by changing specific synthesis parameters, such as changing the microfluidic channels to tune the size of the microdroplets (tens to hundreds of microns), changing the contents of the precursor solution to manipulate the surface morphology (wrinkled to smooth surface) and changing the gelation/annealing conditions to tune the porosity (surface area up to 1021 m2 g-1) and stiffness of the microspheres (elastic modulus tunable from 0.9 GPa to 144.3 GPa). Further investigations indicate that rapid solvent diffusion promotes the formation of dense microspheres while gelation of silica sol induces mesoporous structures; tuning the solvent diffusion and gelation rates enables the modulation of the porous structure and surface morphology, and the surface status further determines the stiffness of the microspheres. The strategy presented here may provide new tools for the on-demand design of next generation monodisperse silica microspheres with precisely controlled properties. It may also provide new insights into the preparation of other monodisperse microspheres with desired functionalities.

Enhancement of Ferroelectric Properties of Ni-Substituted Pb2Fe2O5 Thin Films Synthesized by Reactive Magnetron Sputtering Deposition

Lead ferrite Pb2Fe2O5 (PFO) is a potential multiferroic material due its exhibition of ferroelectric and ferromagnetic properties. The effects of the substitution with nickel and synthesis temperature on the structural, morphological, and ferroelectric properties of lead ferrite thin films were investigated through the use of reactive magnetron sputtering deposition. Nickel loading concentrations were systematically varied (3%, 5%, and 10% by wt.%). X-ray diffraction analysis confirmed the formation of Ni-substituted distorted PFO lattices, while scanning electron microscopy and energy-dispersive spectroscopy indicated a uniform elemental distribution and surface morphology. Polarization vs. electrical field (P−E) measurements showed improved remnant polarization (Pr) with increasing Ni content and synthesis temperatures, achieving a maximum Pr of 66.7 µC/cm2 at 5 wt.% The Ni loading and substrate (Pt/Ti/SiO2/Si, Nanoshel Company, Cheshire, UK) temperature were 600 °C. These findings suggest that optimizing the synthesis parameters such as temperature and substitution content is crucial for controlling the ferroelectric properties of PFO thin films.

Evolution of Methylsilsesquioxane: From Hydrolytic Polycondensation Product to Xerogel

Silica fillers have been a cornerstone in chemical technology due to their versatility, availability, and ease of integration into various formulations. Recent advancements, including chlorine-free synthesis of alkoxysilanes, have paved the way for alternative materials like polymethylsilsesquioxane (PMSSO). This study explores the structural evolution and properties of a hydrophobic PMSSO xerogel, synthesized through hydrolytic polycondensation of methyltriethoxysilane (MTEOS). PMSSO exhibits exceptional hydrophobicity, high specific surface area, and compatibility with polymer matrices, making it a promising filler for applications in rubber products, lubricants, and cosmetics. We developed a straightforward synthesis method for producing PMSSO xerogel that avoids toxic solvents and organochlorosilanes, ensuring safety and sustainability. The reaction conditions, particularly the amount of alkali and neutralization parameters, were found to significantly influence the properties of the final xerogels, such as specific surface area. Optimization of the synthesis parameters allow for obtaining PMSSO xerogels with a specific surface area about 600 m2/g. These findings underscore PMSSO’s potential as a versatile, eco-friendly alternative to conventional silica fillers, offering tailored properties for diverse industrial applications.

Tunable optical Kerr transmittance and structured light by a nanostructured TiO2 bilayer

The contrast in the third-order nonlinear optical properties exhibited by TiO2 nanosheets and TiO2 nanostructured thin films is reported. The effects of the particle morphology of the samples were characterized in order to evaluate their influence in the solid compounds. The implementation of a Z-scan experiment allows us to analyze the optical Kerr effect and the nonlinear optical absorption in the samples studied. A significant reverse saturable absorption and negative refractive index were measured in the TiO2 nanosheets, obtaining a switch in the sign of the nonlinear parameters for the TiO2 nanopowder sample irradiated by nanosecond pulses. Additionally, a vectorial two-wave mixing method was used to observe the evolution of the optical Kerr effect in the TiO2 thin films in tandem configurations proposed with potential applications related to structured light. A clear control in the angular momentum of light, dependent on the nanoscale morphology of the bilayer system, is highlighted. These results, together with the TiO2 versatility, could be very attractive for a handful of different all-optical devices integrated by considering tailored synthesis parameters.

The use of Mahad leaf pellet feed affects the fermentation process and rumen micro-biota in beef cattle

Abstract The study’s objective was to assess how Mahad leaf pellet feed affected the microbial ecology and rumen fermentation in beef cattle. Using a 4×4 Latin square design, 4 Brahman crossbred heifers weighing 250 ± 40 kg (1–1.5 years old) were randomly allocated to each of the following treatments: The powder for concentration in the experiment following: (1) Control (0 g concentrate powder), (2) 50 g concentrate powder, (3) 100 g concentrate powder, and (4) 150 g concentrate powder. The cows received ad libitum rice straw and concentrate at 1% BW. None of the treatments affected ruminal temperature, NH 3 -N, microbial protein production, or pH. Hematocrit (Hct) and blood urea N were unaffected by the addition of Mahad leaf pellet feed. On the other hand, the addition of Mahad leaf pellet feed to the diet led to a linear reduction in the ruminal concentration of acetic acid (P = 0.01) and an increase in the ruminal concentration of propionic acid (P = 0.02). We projected a decrease in ruminal CH 4 production (P = 0.02) as the amount of Mahad leaf pellet feed in the diet increased. The addition of Mahad leaf pellet feed to the diet resulted in a linear decrease in the protozoal population (P = 0.01) as the amount increased. According to the current study, Mahad leaf pellet feed alters ruminal fermentation by reducing the acetate-to-propionate ratio and estimating the amount of CH 3 produced. It has no influence on ruminal pH, microbial synthesis or blood parameters. Decreases in the ruminal protozoa may account for some of the changes in ruminal fermentation parameters. The ideal level for animal feed supplementation is 150 g of the total ration, as supplementing beyond 150 g of the concentrate portion did not significantly enhance these beneficial effects.

Optimised Synthesis of Rhombic dodecahedral Cu2O Nanoparticles: A Pathway to Superior Morphological Control

AbstractCuprous oxide (Cu2O) nanoparticles hold significant promise for photocatalytic applications due to their narrow bandgap and high surface reactivity. This study focuses on the synthesis of rhombic dodecahedral Cu2O (RD‐Cu2O) nanoparticles, totally enclosed by {110} facets, known to exhibit superior photocatalytic performance over the other low‐index crystallographic facets. The precise control over the synthesis conditions can significantly enhance the exposure of this highly active face and therefore improve the catalytic performance of Cu2O nanoparticles, making them superior for applications in pollutant degradation, organic reactions, and artificial photosynthesis. We systematically optimised the synthesis parameters, including reactants concentration, pH and other reaction conditions, to achieve a significant scale up of well‐defined RD‐ Cu2O nanoparticles production, strictly necessary for the use of this photocatalyst on a larger scale. The optimised and scaled up synthesis require 2.0 mmol of CuCl2, 6.0 mmol of Sodium dodecyl sulphate (SDS), 9.6 mmol of NH2OH ⋅ HCl and 7.0 mmol of NaOH added in this order to 400 ml of water at 25 °C. The optimised nanoparticles demonstrated a narrow size distribution and a high degree of crystallographic control. Characterisation techniques such as FESEM, XRD, EPR, UV‐Vis spectroscopy, and XPS confirmed the improved morphological and structural properties of the synthesised RD‐Cu2O nanoparticles.

Deep Eutectic Solvent-Assisted Synthesis of Ni-Graphene Composite Supported on Screen-Printed Electrodes for Biogenic Amine Detection.

Deep eutectic solvents (DES) have emerged as versatile, sustainable media for the synthesis of nanomaterials due to their low toxicity, tunability, and biocompatibility. This study develops a one-step method to modify commercially available screen-printed electrodes (SPE) using laser-induced pyrolysis of DES, consisting of choline chloride and tartaric acid with dissolved nickel acetate and dispersed graphene. The electrodes were patterned using a 532 nm continuous-wave laser for the in situ formation of Ni nanoparticles decorated on graphene sheets directly on the SPE surface (Ni-G/SPE). The synthesis parameters, specifically laser power and graphene concentration, were optimized using the Nelder-Mead method to produce modified Ni-G/SPEs with maximized electrochemical response to dopamine. Electrochemical characterization of the developed sensor by differential pulse voltammetry revealed its broad linear detection range from 0.25 to 100 μM and high sensitivity with a low detection limit of 0.095 μM. These results highlight the potential of laser-assisted DES synthesis to advance electrochemical sensing technologies, particularly for the detection of biogenic amines.

Green Synthesis of Red Fluorescent Carbon Quantum Dots: Antioxidant, Hemolytic, Biocompatibility, and Photocatalytic Applications.

A straightforward one-step hydrothermal method is introduced for synthesizing highly efficient red fluorescence carbon dots (R-CQDs), utilizing Heena leaf (Lawsonia inermis) powder as the carbon precursor. The resulting R-CQDs exhibit excitation at 540nm and emission at 675nm, a high absolute photoluminescence (PL) with quantum yield of 40% in ethanol. Various physicochemical characterization was employed to confirm successful formation of R-CQDs including UV-Vis Spectroscopy, Fourier Transform Infrared (FT-IR) Spectroscopy, X-ray diffraction Spectroscopy, Transmission Electron Microscopy (TEM) and X-ray Photoelectron Spectroscopy. The optimization of synthesis parameters including synthesis method, effect of reaction temperature, effect of reaction time and effect of reaction concentration have a significant impact on the quality and quantity of synthesized R-CQDs, as well as their properties and applications. The effect of pH and UV radiation on synthesized R-CQDs exhibited excellent photo and chemical stability. Furthermore, R-CQDs had a high ability to protect cells from hydrogen peroxide-induced damage by scavenging hydroxyl radicals.In antioxidant activity, all three methods show approximately 80% of DPPH, Fenton's reaction and KMnO4 scavenging activity. In hemolytic assay shows no damage or destruction of red blood cells after exposure of R-CQDs. Cell viability and angiogenesis assays confirmed the biocompatibility of the R-CQDs, indicating that they might be useful as agents for cell labelling and useful for bioimaging probe. In dye degradation activity shows highest % of dye degradation in eosin and fluorescein with approximately 80% of dye degradation by using R-CQDs.

Integration of silver nanostructures in wireless sensor networks for enhanced biochemical sensing.

Integrating noble metal nanostructures, specifically silver nanoparticles, into sensor designs has proven to enhance sensor performance across key metrics, including response time, stability, and sensitivity. However, a critical gap remains in understanding the unique contributions of various synthesis parameters on these enhancements. This study addresses this gap by examining how factors such as temperature, growth time, and choice of capping agents influence nanostructure shape and size, optimizing sensor performance for diverse conditions. Using silver nitrate and sodium borohydride, silver seed particles were created, followed by controlled growth in a solution containing additional silver ions. The size and morphology of the resulting nanostructures were regulated to achieve optimal properties for biochemical sensing in wireless sensor networks. Results demonstrated that embedding these nanostructures in Polyvinyl Alcohol (PVA) matrices led to superior stability, maintaining 93% effectiveness over 30days compared to 70% in Polyethylene Glycol (PEG). Performance metrics revealed significant improvements: reduced response times (1.2ms vs. 1.5ms at zero analyte concentration) and faster responses at higher analyte levels (0.2ms). These outcomes confirm that higher synthesis temperatures and precise shape control contribute to larger, more stable nanostructures.The enhanced stability and responsiveness underscore the potential of noble metal nanostructures for scalable and durable sensor applications, offering a significant advancement over current methods.

Green Synthesis of Zinc Oxide Nanoparticles Including Rosehip (Rosa canina L.) Seed Extract: Evaluation of Its Characterization and Bioactivity Properties.

The use of bioactive compounds in plants as reducing, stabilizing, and capping agents in nanoparticle manufacturing is an exceptionally eco-friendly approach. This work used rosehip seed extract, acquired by automatic solvent extraction, in the microwave-assisted green production of zinc oxide nanoparticles (ZnO NPs). The total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity of the extracted materials and nanoparticles (NPs) were assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. The ideal synthesis parameters were established as 25mL of extract, pH 12, 360W of microwave power, and a metal salt concentration of 0.05M for a duration of 7min. The characterization of the ZnO NPs synthesized under these conditions was performed using x-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy with energy-dispersive x-ray analysis (SEM-EDX), dynamic light scattering (DLS), zeta potential measurements, and UV-Vis spectrophotometry. High-purity, nano-sized, antioxidant ZnO NPs were manufactured using an ecologically friendly, sustainable, and ecological technique.

Investigation of biological activities of silver nanoparticles synthesis from the root extract of endemic Onosma mutabilis (O. mutabilis) Plant

Plant-mediated silver nanoparticles (AgNPs) synthesis appears to be reliable and environmentally friendly, requiring less energy, and cost. Various components present in its natural products can function as strong reducing and capping substrates, ensuring the stability of the resulting NPs. This study synthesized AgNPs with root extracts of O. mutabilis. The effect of many different synthesis parameters (such as silver ion concentration, temperature and reaction pH) of the obtained root extract on the synthesis of AgNPs was also examined. Furthermore, AgNPs were characterized using UV-Vis spectroscopy, Fourier-transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), particle size measurement (Malvern Mastersizer) and energy dispersive X-ray analysis (EDX). The surface plasmon resonance band features of AgNPs were determined in the ultraviolet-visible absorbance spectrum at 410 nm. Total phenolic compound (TPC) determination was analyzed using the Folin-Ciocalteu method, and TPC in AgNPs extracts was determined as 295 ± 0.02 mg GAEs/gr extract. The antioxidant activity of the AgNPs was examined using the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) free radical scavenging activity method. The synthesized AgNPs exhibited strong antioxidant activity. The antidiabetic activity was determined by measuring alpha-amylase inhibition by spectrophotometric method. α-amylase inhibition values were determined to be highest at 31%. The study was further elaborated for determining AgNPs antibacterial using MIC. The biosynthesized AgNPs showed effective antibacterial activity against the Acinetobacter baumannii (A.baumannii) bacteria.Suggests that green biosynthesized AgNPs can constitute an effective antioxidant, antidiabetic and antibacterial agent.

Submicron Dispersions of Phytosterols Reverse Liver Steatosis with Higher Efficacy than Phytosterol Esters in a Diet Induced-Fatty Liver Murine Model.

Consumption of phytosterols is a nutritional strategy employed to reduce cholesterol absorption, but recent research shows that their biological activity might go beyond cholesterol reduction for the treatment of metabolic dysfunction-associated fatty liver disease (MAFLD), and novel phytosterol formulations, such as submicron dispersions, could improve these effects. We explored the therapeutic activity of phytosterols, either formulated as submicron dispersions of phytosterols (SDPs) or conventional phytosterol esters (PEs), in a mouse model of MAFLD. MAFLD was induced in mice by atherogenic diet (AD) feeding. The reversion of distorted serum and liver parameter values after a period of AD feeding was investigated after supplementation of the AD with SDPs, PEs, or a placebo (PT). Additionally, the metabolic parameters of fatty acid synthesis, fatty acid oxidation, and inflammation were studied to understand the mechanism of action of phytosterols. AD supplementation with SDPs was shown to reduce liver fat, along with showing a significant improvement in liver triglycerides (TGs), free fatty acids (FFAs), and liver cholesterol levels. These results were reinforced by the analyses of the liver steatosis scores, and liver histologies, where SDP intervention showed a consistent improvement. Treatment with PEs showed slighter effects in the same analyses, and no effects were observed with the PT treatment. Additionally, SDP intervention reversed, with a higher efficacy than PEs, the effect of AD on the serum levels of TGs, total- and LDL-cholesterol levels, and glucose levels. And, exceptionally, while SDP improved HDL-cholesterol serum levels, PEs did not show any effect on this parameter. We provide evidence for the therapeutical activity of phytosterols in MAFLD beyond the regulation of cholesterol levels, which is increased when the phytosterols are formulated as submicron dispersions compared to ester formulations.

Calcium Phosphate Nanoparticles Functionalized with a Cardio-Specific Peptide.

Cardiovascular diseases (CVDs) remain the leading cause of mortality worldwide, highliting the urgent need for new therapeutic strategies. Peptide-based therapies have demonstrated significant potential for treating CVDs; however, their clinical application is hindered by their limited stability in physiological fluids. To overcome this challenge, an effective drug delivery system is essential to protect and efficiently transport peptides to their intended targets. This study introduces two distinct strategies for loading a cardio-specific mimetic peptide (MP), previously designed to modulate L-type calcium channel function in cardiomyocytes, onto calcium phosphate nanoparticles (CaP NPs). MP-loaded CaP NPs were prepared by two different wet precipitation syntheses, one of which involved the use of sodium polyacrylate as a templating agent. Characterization of MP-loaded CaP NPs showed that their crystallinity, size, surface charge, and morphology could be tuned by adjusting the synthesis parameters. In vitro tests on cardiac cells confirmed that both types of MP-loaded CaP NPs are biocompatible with HL-1 cardiomyocytes and restored intracellular calcium flux under stressed conditions, highlighting their therapeutic potential. These results pave the way for further optimization of CaP NP formulations and suggest their potential as a viable nanomaterial for CVD treatment.

Synthesis, Characterization, and antibacterial activity of Combine Mentha piperita - Silver nanoparticle on Multi-drug Resistant Hypervirulent Klebsiella pneumoniae from clinical sources

Background and Aim Silver nanoparticles (AgNPs) are recognized for their strong theragnostic properties and diverse applications in biomedical fields, including their effective use as antimicrobial agents. The study aimed to synthesize AgNPs using aqueous M. piperita extract and test its antibacterial activity against MDR-HvKp isolated from clinical sources. Methods The AgNPs were synthesized using M. piperita, physicochemical characterize EC, TDS, TDO, Ph, FTIR, and SEM. The antibacterial activity of M. piperita extract, AgNO3, and synthesized AgNPs was measured using the agar diffusion method, MIC, and MBC. Electrical conductivity of AgNPs (2130 µS/cm, normal range: 0-2500 µS/cm). Results Total dissolved solids (AgNPs: 768 ppm, normal range: 50-300 ppm), dissolved oxygen AgNPs: (3.20 mg/L, normal range: 6.5-8.0 mg/L), and pH, AgNPs: (7.0, normal range: 6.5-7.6). The AgNPs with size 400 nm (2.08 absorbance), after a 7days incubation period. The FTIR indicates AgNPs are capped with organic molecules, with peaks related to various organic functional groups such as C-H, C=O, and C-O are present. The SEM findings validated the production of spherical AgNPs with a crystalline structure and an average diameter of 20.42 nm. The M. piperita-AgNp conjugate record high MIC of 16mm(30 µg/ml) 14mm(25 µg/ml), 10mm(20 µg/ml) and 8mm(15 µg/ml). Followed by AgNPs with 6mm (30 µg/ml) and 4mm(15 µg/ml), whereas Mentha piperita records 10mm(30 µg/ml) and 4mm(15 µg/ml), with an MIC of 20µg/ml and MBC of 25µg/ml. Conclusion M. piperita's bioactive components enhance AgNP synthesis and antimicrobial activity against MDR-HvKp. Future research is needed to optimize component concentrations, synthesis parameters, and extraction methods for broader pathogen efficacy.

Black phosphorus-based nanoplatforms for cancer therapy: chemistry, design, biological and therapeutic behaviors.

Cancer, a significant threat to human lives, has been the target of research for several decades. Although conventional therapies have drawbacks, such as side effects, low efficacy, and weak targeting, they have been applied extensively due to a lack of effective alternatives. The emergence of nanotechnology in medicine has opened up new possibilities and offered promising solutions for cancer therapy. In recent years, 2D nanomaterials have attracted enormous attention in nanomedicine due to their large surface-to-volume ratio, photo-responsivity, excellent electrical conductivity, etc. Among them, black phosphorus (BP) is a 2D nanomaterial consisting of multiple layers weakly bonded together through van der Waals forces. Its distinct structure makes BP suitable for biomedical applications, such as drug/gene carriers, PTT/PDT, and imaging agents. BP has demonstrated remarkable potential since its introduction in cancer therapy in 2015, particularly due to its selective anticancer activity even without the aid of near-infrared (NIR) or anticancer drugs. The present review makes efforts to cover and discuss studies published on the anticancer activity of BP. Based on the type of cancer, the subcategories are organized to shed light on the potential of BP nanosheets and BP quantum dots (BPQDs) against breast, brain, skin, prostate, and bone cancers, and a section is devoted to other cancer types. Since extensive attention has been paid to breast cancer cells and in vivo models, various subsections, including mono-, dual, and triple therapeutic approaches are established for this cancer type. Furthermore, the review outlines various synthesis approaches employed to produce BP nanomaterials, providing insights into key synthesis parameters. This review provides an up-to-date platform for the potential reader to understand what has been done about BP cancer therapy based on each disease, and the conclusions and outlook cover the directions in which this approach is going to proceed in the future.

Enhancement of stability and activity of zinc carbonate nanoparticles using chitosan, hydroxyethyl cellulose, methyl cellulose and hyaluronic acid for multifaceted applications in medicine.

Currently, biopolymer-based Zn-containing nanoforms are of great interest for medical applications. However, there is lack information on optimal synthesis parameters, reagents and stabilizing agent for production of zinc carbonate nanoparticles (ZnC-NPs). In this work, synthesis of ZnC-NPs was carried out by chemical precipitation with the use of chitosan, hydroxyethyl cellulose, methyl cellulose and hyaluronic acid as stabilizing agents. The optimal precursor (Zn(CH3COO)2) and the optimal precipitator ((NH₄)₂CO₃) were detected. ZnC-NPs had one phase (Zn5(OH)6(CO3)2) with diameter from 35 to 120 nm. Thus, the optimal synthesis parameters were set as stoichiometric ratio of precursor and precipitator and the maximum concentration of biopolymer. It was found that polymers are sorbed on different crystallographic planes of crystallites, which affects the morphology of Zn5(OH)6(CO3). Quantum chemical modelling revealed that all models of interaction are energetically advantageous (∆E > 9788.910 kcal/mol) and preferably occurs through OH group, which was confirmed by FTIR spectroscopy of synthesized samples. Notably, CAM assay and histological evaluation showed that ZnC-NPs stabilized with chitosan (as represent of considered biopolymers) have no toxic effect and are compatible with CAM biological environment, which open a great potential for further studies of ZnC-NPs stabilized with biopolymers for multifaceted applications in medicine.

A review of the synthetic strategies toward the antiviral drug tecovirimat.

This review provides a comprehensive analysis of synthetic routes for tecovirimat, an antiviral drug used to treat orthopoxvirus infections, including monkeypox and smallpox. We focus on the scale-up synthesis of key intermediates, including cycloheptatriene, as documented in the published literature and patent records. The review highlights the efficiency, yield, and purity of these approaches, as well as the minimization of genotoxic and in-process impurities. Furthermore, we critically evaluate the recently reported optimized industrial-scale synthesis process, highlighting its advantages and limitations, and identifying avenues for further improvement. By obtaining insights from the published literature and patent records, this review elucidates the current state of knowledge regarding key synthesis parameters influencing tecovirimat production and emphasizes the critical importance of optimizing synthesis techniques to achieve remarkable improvements in safety and environmental impact. This review serves as a valuable resource for researchers and industry professionals in the field of R&D and production of APIs, particularly in expediting the safe and efficient industrial production of tecovirimat.

Electrical, Optical & Structural characteristics of reduced graphene oxide: A comparative analysis using different reducing agents

The study of optical and electrical properties of functionalised materials of GO and rGO are crucial for their different applications in energy storage, optoelectronics and biosensing. The structural disorder occurring during the synthesis process largely affects the optical properties of the materials. In this work we have tried to study the variation in optical and electrical properties of rGO by varying the synthesis parameters. Different rGO samples prepared from the same precursor (graphite powder) by using various reducing agents are studied. It is observed that the physical conditions during the synthesis process affect the bandgap of the synthesised samples. This study is correlated with the elemental analysis, surface morphology and defect studies.

“Inverse” shape memory effect in energetic electron crosslinked methylcellulose hydrogels: Programming, demonstration and quantification

Shape memory hydrogels constitute a highly attractive materials class that bears enormous potential within a broad range of areas – from engineering to medicine. Within the present contribution we demonstrate that energetic electron crosslinked methylcellulose-only hydrogels exhibit an “inverse” shape memory effect that trans- forms from a secondary shape to its primary shape upon cooling. The primary shape can conveniently be “programmed” by application of energetic electrons. This intrinsically sterilizing processing approach promises to preserve the excellent FDA- approved biocompatibility of methylcellulose, particularly as it does not involve potentially hazardous crosslinkers or other reagents with medically adverse effects. While we observe the transformation behavior in a systematic study as function of synthesis parameters, we also address functional fatigue and quantify fixity, strain recovery as well as attainable actuator forces. With the latter being in the range of 0.1 N, our actuator elements might prove useful for biomedical applications.

Tuning the optical depolarization and absorption in freestanding ZnO nanorod/nanotube arrays decorated with SnS nanoparticles through control of the synthesis parameters

Tuning the optical depolarization and absorption in freestanding ZnO nanorod/nanotube arrays decorated with SnS nanoparticles through control of the synthesis parameters