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The synthesis of silver nanoparticles (AgNPs) using Annona muricata(A. muricata) leaf extract and its larvicidal, metabolic enzyme inhibitory properties was demonstrated here. The AgNPs were synthesized and analyzed by using UV-visible spectroscopy and observed a maximum absorbance peak at 420 nm which corresponds to the AgNPs. The XRD analysis showed the 2θintense values (111, 200, 220, and 311) within the ranges of Bragg’s reflection; Fourier transform infrared spectroscopy (FTIR) showed that AgNPs were capped with alkanes, amides, and alkenes functional groups which act as a reducing, capping, and stabilizing agent; and field emission scanning electron microscope (FESEM) and high-resolution transmission electron microscopy (HRTEM) results indicated that synthesized AgNPs were spherical in shape with the size of 20–34 nm and energy-dispersive X-ray (EDX) spectroscopy exhibited a strong signal of silver. Various concentrations of AgNPs (6, 12, 18, 24, 30 μg mL−1) and aqueous leaf extract (ALE) (30, 60, 90, 120, 150 μg mL−1) were evaluated, and in all the concentrations, AgNPs showed significant larvicidal properties against three different second instar larvae, when compared to ALE. ALE exhibited LC50and LC90values of (LC5045.521 μg/mL; LC90456.406 μg/mL) against Ae. aegyptifollowed by An. stephensi(LC5061.878 μg/mL; LC90565.309 μg/mL) and Cx. quinquefasciatus(LC5068.952 μg/mL; LC90444.512 μg/mL), and AgNPs were exhibited LC50and LC90values (LC503.089 μg/mL; LC9018.467 μg/mL) against Ae. aegyptifollowed by An. stephensi(LC503.155 μg/mL; LC9039.888 μg/mL) and Cx. quinquefasciatus(LC505.188 μg/mL; LC9031.660 μg/mL), respectively. The A. muricataleaf extract-mediated AgNPs were also evaluated for the first time to identify their metabolic enzyme inhibitory activity which also showed significant results.

In this innovative work, the fillers obtained by grinding Samanea Saman flowers were utilized for the fabrication of PLA biocomposites. Melt compounding of SSF fillers and PLA with a co-rotating twin-screw extruder permits the simple production of biocomposites with a substantial stage of filler distribution. The elemental compositions and surface morphology of PLA/SSF biocomposite were analyzed using energy dispersive X-ray (EDX) and scanning electron microscopy (SEM) apparatus. The crystalline structure of the PLA/SSF

Aim: This in vitrostudy compared the fatigue resistance of two polymeric materials (Nylon and Polytetrafluoroethylene (PTFE)) used as retentive attachments in implant-retained overdentures after immersion in denture cleansing solution.Materials and Methods: A total of 24 samples (N=24), of which 12 capsule-shaped samples of commercially available nylon material from ADIN dental implants, India, and similar sized and shaped 12 PTFE (medical grade) capsules custom fabricated from AAA Industries, Mumbai was obtained. Six samples of each material were immersed in distilled water and six samples in Clinsodent denture cleanser, simulating an 8–h daily immersion of the denture for a period of 2 years. After completion of the immersion protocol, samples were subjected to 2900 fatigue cycles using the Universal Testing Machine (UTM), simulating 4 cycles per day of removal and insertion of the overdenture for a duration of 2 years. Before and after immersion, the wear of the samples was assessed for internal and external diameter changes using the Sipcon Inspection System. The statistical analysis of the obtained results was tested by applying the paired-t test, Fisher analysis of variance, and Tukey’s honest significant difference test, with a probability value less than0.05 used as statistically significant.Results: Statistically significant differences were observed after immersion in denture cleanser for nylon and PTFE. The greatest fatigue for ID, IHL, and IVL was demonstrated in nylon immersed in Clinsodent at p= .000. ED and EHL of PTFE in distilled water showed greater deformation than others (p= .000).Conclusion: PTFE attachments have shown better fatigue resistance after immersion in Clinsodent denture cleanser. Nylon material immersed in distilled water as well as in Clinsodent cleanser showed greater deformation after fatigue cycles.

Microbial fuel cells (MFC) and microbial electrolysis cells (MEC) are developing as sustainable power source technologies that can be utilized for feasible wastewater treatment and hydrogen production. Hydrogen gas has immense potential as an ecologically adequate energy carrier for vehicles. MFC is bioelectrochemical process that utilize microorganism as the impetuses to oxidize organic and inorganic matter and create electricity, whereas MEC are a reactor for biohydrogen production by combining MFC and electrolysis. MEC and MFC have been the cleanest, eco-friendly, and efficient method for biohydrogen production. The basic mechanism and thermodynamic principles involved in the production of hydrogen have been discussed in brief. Effective factors influencing H2production such as microbial population, electrodes, membrane, and substrate were elaborated and recent advances in the factors have been explored for the better understanding of developing MFC and MEC technology-based hydrogen generation. This review completes a brief outline of topical advances in the MFC, MEC setup, and different operational parameters which influencing hydrogen production (ionic strength, applied voltage, organic loading, and hydraulic retention time). The review describes the current challenges involved in the technology used and provides effective future perspectives for overcoming the limitations.

In this work, we report the reactivity of the carboranyl diphosphine, 1-PtBu2–2-PiPr2-C2B10H10, with terminal alkynes, resulting in the formation of boron-containing phosphacycles. The reported system combines the nucleophilic activation of electron-deficient terminal alkynes via electron-rich phosphine groups with the redox behavior of carborane clusters to promote a sequence of metal-free intramolecular B–H bond activation and cyclization, creating an alkenylphosphonium cycle fused with a reduced open nido-carborane cluster.

Tuning metal oxidation states in metal–organic framework (MOF) nodes by switching between two discrete linker photoisomers via an external stimulus was probed for the first time. On the examples of three novel photochromic copper-based frameworks, we demonstrated the capability of switching between +2 and +1 oxidation states, on demand. In addition to crystallographic methods used for material characterization, the role of the photochromic moieties for tuning the oxidation state was probed via conductivity measurements, cyclic voltammetry, and electron paramagnetic resonance, X-ray photoelectron, and diffuse reflectance spectroscopies. We confirmed the reversible photoswitching activity including photoisomerization rate determination of spiropyran- and diarylethene-containing linkers in extended frameworks, resulting in changes in metal oxidation states as a function of alternating excitation wavelengths. To elucidate the switching process between two states, the photoisomerization quantum yield of photochromic MOFs was determined for the first time. Overall, the introduced noninvasive concept of metal oxidation state modulation on the examples of stimuli-responsive MOFs foreshadows a new pathway for alternation of material properties toward targeted applications.

Hydroxyapatite (HAp) is the major inorganic component of natural bone which exhibits better biocompatibility with various kinds of cells and tissues, making it an ideal candidate for dental and orthopedic applications. The naturally extracted HAp (Ca10(PO4)6(OH)2) from fish scale and seashell is exactly matched with the chemical composition of bone minerals. Nowadays, soft chemistry is used for the synthesis of bioceramics such as HAp. This is a chemical route that yields more homogeneous solid-state materials. In this study, the extracted powder from fish scale and seashell was heated in the furnace and maintained at 700°C for 3 hours and the powder was naturally cooled. The derived CaO was used for preparing HAp by the microwave irradiation techniques. The HAp was filled with High-Density Polyethylene (HDPE) in the ratio of 10:3 (Matrix 100 g: Filler 30 g) and composite was fabricated by the injection molding. The functional groups present in the HAp-HDPE specimen was identified using Fourier Transform Infrared (FTIR) spectroscopy analysis. The thermal stability of 30 wt. % HAp-HDPE composite was analyzed using Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). In vitrocytotoxicity studies were carried out using MG63 cell line. In these studies, five different volumes of liquid extracts of the prepared HAp-HDPE specimen having different concentrations (10, 20, 30, 40, and 50 μl) were allowed to interact with fresh cell culture medium for 24 hours. The cell morphology, cell viability, and the levels of cytotoxicity of the composite specimen were studied as per 10993:12, and ISO 10993:5 test standards.

We report metal-free bond activation by the carboranyl diphosphine 1-PtBu2-2-PiPr2-C2B10H10. This main group element system contains basic binding sites and possesses the ability to cycle through two-electron redox states. The reported reactions with selected main group hydrides and alcohols occur via the formal oxidation of the phosphine groups and concomitant reduction of the boron cage. These transformations, which are driven by the cooperation between the electron-donating exohedral substituents and the electron-accepting cluster, differ from those of “regular” phosphines and are reminiscent of oxidative addition to transition metal centers, thus representing a new approach to metal-free bond activation.

AbstractA graph G= (p, q) is said to have a restricted k-mean labeling if there is an injective function ffrom the vertices of Gto {k– 1, k, k+ 1, … , k + q– 1} such that when each edge uvis labeled with then the resulting edge labels {k, k+ 1, k+ 2, … , k + q– 1} are all distinct where kis a positive integer greater than or equal to one. A graph that admits a restricted k-mean labeling is called a restricted k-mean graph.

The rising concern over global climate change has geared up a desire for reduction in greenhouse gas emissions. In this work, a systematic review of the literature work done so far on the application of adsorption and hydrate-based gas separation for the capture of CO2from both fuel gas and flue gas mixtures has been carried out. Different adsorbents and operating conditions have been studied. Improvements in the adsorption capacities by thermal, mechanical and chemical activation have also been analysed. A range of reactor designs and the role of thermodynamic and kinetic promoters in the hydrate-based gas separation process for CO2capture have been reviewed. Each experimental work has been scrutinised independently and compared finally. Furthermore, the advantages and limitations of adsorption process and hydrate-based gas separation process have been pointed out.

High Peak to Average Power Ratio (PAPR) of OFDM reduces transmitter power efficiency and increases complexity in hardware implementation. In the paper, the high PAPR is reduced using optimized Standard Deviation based Iterative Clipping and Filtering (SD-ICF).The proposed method achieves a greater reduction in PAPR in a few iterations with reduced out-of-band distortion and bit error rate when compared over classical clipping techniques.Also, the effects of oversampling on the performance of proposed OFDM system is discussed.

Tomato (Lycopersicon esculentum Mill. cv. PKM 1) plants growing under field conditions were exposed for 15 d to solar radiation with UV-B component (280 - 320 nm) enhanced to 6.3 kJ m-2 d-1. This simulated a 15% stratospheric ozone depletion over Madurai (9° 50′ N latitude). Lipid peroxidation in the leaves of UV-B treated plants was 32% higher compared to the control. Superoxide dismutase (SOD) and catalase activities registered parallel promotion by 126 and 50 %, respectively, in the UV-B treated plants. Further, the contents of total phenols and anthocyanins in the leaves have also been enhanced by 40 and 156%, respectively. On the contrary, polyphenol oxidase activity demonstrated a 58 % inhibition in the leaves of UV-B treated plants. While anthocyanins and phenols are proposed to act as antioxidants, the reduction in polyphenol oxidase activity may maintain the turnover of phenols in the UV-B treated plants.

The synthesis of well-defined heterometallic complexes remains a frontier challenge in inorganic chemistry. We report an approach that relies on the sequential insertion of electrophilic metal fragments into electron-rich Ru–B bonds of the η2-BB-carboryne complex (POBBOP)Ru(CO)2[POBBOP = 1,7-OP(iPr)2-m-2,6-dehydrocarborane]. Utilizing this synthetic strategy, bimetallic (POBBOP)(Ru)(CO)2[Pd(PtBu3)] and trimetallic (POBBOP)(Ru)(CO)2[Pd(PtBu3)](CuBr) complexes were selectively prepared. Structural and theoretical analysis of the features of chemical bonding within Ru–B–B–Cu and Ru–B–B–Pd fragments is presented.

•Novel N-(2,6-dichlorophenyl)-4-(naphthalen-2-yl)-1,3-thiazol-2-amine (6) was confirmed by FT-IR, 1H-NMR, Mass spectrum and elemental analyses.•The x-ray diffraction studies revealed that compound (6) crystallized in triclinic system with the space group P-1.•The percentage of intermolecular contacts contributing to Hirshfeld surface in thiazole crystal was resolved by Hirshfeld surface analyses with 2D finger print plots.

Serious environmental problems by means of increasing the production of Ordinary Portland cement (OPC), which is conventionally used as the primary binder to produce cement concrete. An attempt has been made to reduce the use of ordinary Portland cement in cement concrete. There is no standard mix design of geo-polymer concrete, an effort has been made to know the physical, chemical properties and optimum mix of geo-polymer concrete mix design. Concrete cubes of 100 x 100 x 100 mm were prepared and cured under steam curing for about 24 hours at temperature range of 40degC to 60degC. Fly ash is replaced partially with rice husk ash at percentage of 10%, 15% and 25%. Sodium hydroxide and sodium silicate are of used as alkaline activators with 5 Molar and 10 Molar NaOH solutions. Natural sand is replaced with manufacture sand. Test results were compared with controlled concrete mix of grade M30. The results shows that as the percentage of rice husk ash and water content increases, compressive strength will be decreases and as molarity of the alkaline solution increases, strength will be increases.