Palladium (0) nanoparticles distributed on lanthanum (III) oxide as an effective catalyst for the methanolysis of hydrazine-borane to produce hydrogen.

Pd (0) nanoparticles (NPs) distributed on lanthanum (III) oxide were ex situ generated from the reduction of Pd2+ ions using NaBH4 as reducing agent. The Pd/La2O3 displayed good catalytic activity in H2(g) releasing from the hydrazine-borane (HB) methanolysis reaction and it was identified by advanced techniques. Pd/La2O3 was found to be an active catalyst procuring three equiv. H2(g) per mole of HB. The results from TEM images represent the formation of Pd (0) NPs with an average particle size of 1.94 ± 0.1 nm on the surface of La2O3. Moreover, Pd/La2O3 with various Pd loadings were prepared and tested as catalyst in the methanolysis reaction to find the optimum metal loading on La2O3 support. The highest H2 formation rate was achieved with 3.0 wt% Pd. Pd/La2O3 catalyst exhibited a turnover frequency (TOF) value of 24.4 mol H2 mol Pd-1 min-1 in the reaction conditions. Additionally, the effect of different catalyst concentrations and temperatures on the reaction kinetics for the methanolysis of HB catalyzed by Pd/La2O3.

Pericardiectomy after constrictive pericarditis associated with second dose of BNT162b2 vaccine: A case report.

Constrictive pericarditis is quite rare complication of messenger ribonucleic acid-based severe acute respiratory syndrome-Coronavirus 2 (SARS-CoV-2) vaccine. It is a severe clinical picture with clinical symptoms of right ventricular failure. Initial physical examination, laboratory work-up, and chest X-ray may yield non-specific findings. Echocardiography, computed tomography, and cardiac catheterization are other diagnostic tools. Surgery with pericardiectomy is the definitive treatment option. Herein, we report a case of pericardiectomy after constrictive pericarditis associated with the second dose of BNT162b2 vaccine.

Synthesis and characterization of Pd0 nanoparticles supported over hydroxyapatite nanospheres for potential application as a promising catalyst for nitrophenol reduction.

Nitrophenols, which are defined as an important toxic and carcinogenic pollutant in agricultural and industrial wastewater due to their solubility in water, form of resistance against all organisms in water resources. It is vital that these compounds, which are highly toxic as well as highly explosive, are removed from the aquatic ecosystem. In this paper, we reported the preparation and advanced characterization of Pd0 nanoparticles supported over hydroxyapatite nanospheres (Pd0@nano-HAp). The catalytic efficiency of the Pd0@nano-HAp catalyst was examined in the reduction of nitrophenols in water in the presence of NaBH4 as reducing agent and the great activity of catalyst have been specified against 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol and 2,4,6-trinitrophenol compounds with 70.6, 82.4, 27.6 and 41.4 min-1 TOFinitial values, respectively. Another important point is that the Pd0@nano-HAp catalyst has perfect reusability performance (at 5th reuse between 68.5 and 92.8 %) for the reduction of nitrophenols. In addition, catalytic studies were carried out at different temperatures in order to determine thermodynamic parameters such as Ea, ΔH≠ and ΔS≠.

A novel highly active and reusable carbon based platinum-ruthenium nanocatalyst for dimethylamine-borane dehydrogenation in water at room conditions.

In this paper, we present platinum/ruthenium nanoparticles supported on Vulcan carbon (PtRu@VC) as a nanocatalyst for the dehydrogenation of dimethylamine-borane (DMAB) in aqueous solution under mild conditions. PtRu@VC nanocatalyst was fabricated using the alcohol-reduction techniques which is a facile and effective method. The prepared PtRu@VC nanocatalyst exhibited a good stabilization and an effective catalytic activity for hydrogen evolution from the DMAB dehydrogenation in water at room temperature. The composition of PtRu@VC nanocatalyst was investigated using different analytical techniques inductively coupled plasma optical emission spectroscopy (ICP-OES), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), powder X-ray diffraction (P-XRD) and X-ray photoelectron spectroscopy (XPS). A monodispersedPt/Ru metals distributions on VC (as supporting material) were revealed by TEM and HR-TEM analyses. The mean particle size of PtRu@VC nanocatalyst was found to be 3.15 ± 0.76 nm. XPS analysis for PtRu@VC nanocatalyst showed that almost Pt-Ru metals were found to be the metallic state. Catalytic experimental results showed that PtRu@VC nanocatalyst has a high catalytic activity with an excellent turn-over frequency (TOFinitial) value of 14926.2 h-1 (248.77 min-1) in the dehydrogenation of DMAB in water at room temperature. Additionally, in the paper, we report some different kinetic data obtained from different experimental parameters of temperature, catalyst and substrate concentrations conducted for DMAB dehydrogenation in water catalyzed with PtRu@VC nanocatalyst.

Synthesis and characterization of Reishi mushroom-mediated green synthesis of silver nanoparticles for the biochemical applications.

In recent years, the synthesis of nanoparticles via biological processes has attracted considerable attention. The use of plants and plant extracts is one of the most preferred methods for biological synthesis due to their rich biologically active metabolites. In this study, silver nanoparticles (Ag NPs) were synthesized using reishi mushroom (Ganoderma lucidum) extract. Different analytical techniques including X-ray Photoelectron Spectroscopy (XPS), X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-vis spectroscopy, and Fourier Transform Infrared Spectrophotometer (FTIR) were used for the characterization of Ag NPs. UV-vis spectrum exhibited a broad absorption peak between 400-460 nm which indicates the existence of Ag NPs. TEM images showed Ag NPs are spherical with a diameter range of 15-22 nm. In addition, it is shown that Ag NPs form a face-centered cubic structure according to XRD characterization technique. The antioxidant activity towards to 1-Diphenyl-2-picrylhydrazyl (DPPH) was also studied. The highest DPPH scavenging percentage was recorded as 76.45% at 250 mg/L. The DNA cleavage activity results indicated that the green Ag NPs caused single strain DNA cleavage activity for 30 and 60 min at 50 and 100 mg/L, respectively. The Ag NPs antimicrobial activity was also investigated and results recorded as minimum inhibition concentration (MIC). Ag NPs showed a strong antibacterial effect against gram-positive (S. aureus, E. hirae, B. cereus) and gram-negative (E. coli, P. aeruginosa, L. pneumophila subsp. Pneumophila) bacteria. Furthermore, Ag NPs have also been shown to have a high antifungal effect against C. albicans fungus.

Synthesis and characterization of Rosa canina-mediated biogenic silver nanoparticles for anti-oxidant, antibacterial, antifungal, and DNA cleavage activities.

In biomedical applications, silver nanoparticles (Ag NPs) are of great interest due to their cost-effective and environmentally friendly properties. Green synthesis of nanoparticles for biological research is a preferred choice since it does not require additional reducing agent. For this purpose, in this study, we aimed to synthesize the biogenic silver nanoparticles with the help of Rosa canina plant (Rc-Ag NPs) and then they have been tried for their antioxidant and antibacterial properties. UV-Vis spectrophotometer, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analyses were performed for characterization of Rc-Ag NPs. Antioxidant properties of silver nanoparticles synthesized with Rosa canina plant were investigated against 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH). DNA dissociation activity of synthesized Rc-Ag NPs was studied, and DNA dissociation activity was shown. The antimicrobial activity of Rc-Ag NPs was also tested using micro-dilution. According to the results, Rc-Ag NPs synthesized were found to be highly effective for anti-oxidant, antibacterial, antifungal, and DNA cleavage activities.

Polypyrrole-multi walled carbon nanotube hybrid material supported Pt NPs for hydrogen evolution from the hydrolysis of MeAB at mild conditions.

Herein, we report a facile method for the preparation of polypyrrole-multi walled carbon nanotube hybrid material including Pt nanoparticles (Pt@PPy-MWCNT NPs) and the use in methylamine borane (MeAB) for hydrolysis reaction at mild conditions. The prepared catalyst of Pt@PPy-MWCNT NPs was characterized by some advanced analytical methods. The catalytic experiments showed the Pt@PPy-MWCNT NPs can catalyze MeAB in aquatic solution with high catalytical performance at mild conditions. The reaction rate of catalytic hydrolysis with Pt@PPy-MWCNT NPs was found to be -d[CH3NH2BH3]/dt = + d[H2]/3dt = kobs[Pt@PPy-MWCNT]1.19 [MeAB]0.88. The TOF value for the hydrolysis of MeAB catalyzed with Pt@PPy-MWCNT NPs was detected to be 10234.2 1/h (170.57 1/min) which is very high compared with TOF values found for other catalysts. Enthalpy, entropy and activation energy for the hydrolysis of MeAB were calculated to be 31.57 kJ mol-1, -119.97 J mol-1 K and 34.27 kJ mol-1, respectively.

Single-walled carbon nanotube supported Pt-Ru bimetallic superb nanocatalyst for the hydrogen generation from the methanolysis of methylamine-borane at mild conditions.

Several metal nanoparticle based catalysts have been synthesized for catalyzing the hydrogen production process by hydrolysis of methylamine-borane (MeAB). However, there was only one study that catalyzes the producing of hydrogen via the methanolysis of MeAB, and it was carried out by our research group. For this reason, in this work, a new catalyst system entitled by single-walled carbon nanotube (SWCNT) supported bimetallic platinum-ruthenium nanoparticles were developed and called as PtRu@SWCNT. These NPs were characterized by several techniques (XRD, XPS, Raman, and TEM), and they were performed for the methanolysis of MeAB with high catalytic activity. The prepared PtRu@SWCNT NPs were also tested in the methanolysis of MeAB at different parameters including different temperatures, catalyst and substrate concentrations, and reusability performance. Experimental results revealed that the new PtRu@SWCNT NPs had excellent catalytic activity and reusability for removing of hydrogen from the methanolysis of MeAB at ambient conditions. According to the obtained data, the turnover frequency is 136.25 mole H2/mole PtRu × min, and the activation energy (Ea) is 17.29 kJ/mole. More than 99% of conversion was observed at room temperature.

Ex situ synthesis and characterization of a polymer-carbon nanotube-based hybrid nanocatalyst with one of the highest catalytic activities and stabilities for the hydrolytic dehydrogenation of hydrazine-borane at room temperature conditions.

In this study, a facile ex situ synthesis of a polyaniline-multiwalled carbon nanotube-based Pt nanocatalyst (Pt@PANI-MWCNT) with an average particle size of 3.18 ±â€¯0.12 nm was performed successfully. The obtained Pt@PANI-MWCNT nanocatalysts were isolated from the solution medium by centrifugation and then were characterized by spectroscopy and microscopy methods. The characterization studies showed that the prepared Pt nanoparticles were formed on PANI-MWCNT surface, and H2 evolution was obtained by the dehydrogenation of hydrazine-borane in water as a model reaction under room temperature conditions, with the help of the synthesized nanocatalyst. It was observed that the Pt@PANI-MWCNT nanocatalyst had a very high catalytic activity for the hydrolytic dehydrogenation of hydrazine-borane and generated 2.95 mol of H2 for 1 mol of hydrazine-borane. The initial turn-over frequency (TOFinitial) value of the prepared nanocatalyst for the model reaction at room temperature conditions was found to be 168.5 min-1. The calculations for the kinetics of the hydrolytic dehydrogenation reaction showed that the hydrazine-borane catalytic reaction kinetics are first order, with respect to the catalyst concentration; several activation parameters, such as entropy (ΔS#, app = -72.11 ±â€¯3 J/mol K), enthalpy (ΔH#, app = 43.5 ±â€¯2 kJ/mol) and activation energy (Ea,app = 45.5 ±â€¯2 kJ/mol), of the catalytic reaction with the Pt@PANI-MWCNT nanocatalyst were calculated using these kinetic data.

Palladium nanoparticles decorated on amine functionalized graphene nanosheets as excellent nanocatalyst for the hydrogenation of nitrophenols to aminophenol counterparts.

We reported the improved catalytic property of Pd (0) nanoparticles decorated on amine-functionalized graphene nanosheets (Pd/GNS-NH2) for the hydrogenation of nitrophenol derivatives in the presence of NaBH4 at moderate conditions. Pd/GNS-NH2 nanocatalyst was synthesized by the deposition-reduction method. Sundry techniques such as ICP-OES, P-XRD, XPS, TEM, HR-TEM and EDX have been applied to explain the structure and morphology of the Pd/GNS-NH2 nanocatalyst. The results show that the Pd (0) nanoparticles are perfectly dispersed on the surface of the GNS-NH2 support material (dmean = 1.38-2.63 nm). The catalytic activity of the Pd/GNS-NH2 nanocatalyst was tested in the hydrogenation of nitrophenol derivatives in water in the presence of NaBH4 as reductant and the excellent activity of nanocatalyst have been detected against 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol and 2,4,6-trinitrophenol derivatives with 116.8, 65.9, 42.8 and 11.4 min-1 initial TOF values, respectively. Another important point is that the nanocatalyst has very high reusability performance (at 5th reuse between 71.5 and 91.5%) for the hydrogenation of nitrophenols. Finally, catalytic studies have been carried out at various temperatures to calculate the Ea, ΔH≠ and ΔS≠.

Carbon-nanotube-based rhodium nanoparticles as highly-active catalyst for hydrolytic dehydrogenation of dimethylamineborane at room temperature.

In this study, we present a carbon nanotube-based Rh nanomaterial as a highly active catalyst for the hydrolytic dehydrogenation of dimethylamine - borane (DMAB) at room temperature. The prepared multi-walled carbon nanotube based Rh nanoparticles, called Rh NPs@ MWCNT, was readily prepared, stabilized and effectively used for the hydrolytic dehydrogenation of DMAB under ambient conditions. Monodisperse Rh NPs@ MWCNT nanocatalyst was characterized by using advanced analytical methods such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM) etc. These analytical methods revealed that Rh nanoparticles on the surface of MWCNT were well dispersed and the average particle size was found to be 1.44 ±â€¯0.17 nm. The catalytic experiments revealed that the new Rh NPs@MWCNT nanocatalyst has a high catalytic effect to obtain hydrogen in 3.0 equation from DMAB, and the record catalytic TOF value for the catalytic reaction catalyzed by Rh NPs@MWCNT nanocatalyst was found to be 3010.47 h-1 at room temperature. The current study presents the detailed kinetic studies of the hydrolytic dehydrogenation of DMAB catalyzed by Rh NPs@MWCNT, the results of catalytic experiments were performed at different temperatures, substrate and catalyst concentrations, the Rh NPs@MWCNT nanocatalyst was effectively used in the completion of the hydrolytic dehydrogenation of DMAB, and activation energy, enthalpy and entropy parameters. The experimental results showed that monodisperse Rh NPs@MWCNT nanocatalyst have record catalytic activity with TOF value of 3010.47 h-1, and Rh(0) nanoparticles were well dispersed on the multi-walled carbon nanotubes.

Transition Metal (II) Complexes with a Novel Azo-azomethine Schiff Base Ligand: Synthesis, Structural and Spectroscopic Characterization, Thermal Properties and Biological Applications.

The pyrimidine based azo-linked Schiff base ligand, 5-benzoyl-1-((E)-(2-hydroxy-3-methoxy-5-((E)phenyldiazenyl)benzylidene)amino)-4-phenylpyrimidin-2(1H)-one (HL), and its transition metal (II) complexes were synthesized and defined by using 1H-NMR, 13C-NMR, Elemental analysis, FT-IR, MS, UV-vis, molar conductance, magnetic susceptibility and thermal analysis techniques. According to the conductance data obtained indicate all of the metal complexes have non-electrolytic nature. Square pyramidal geometry for Pd(II) and octahedral geometry for all the other complexes synthesized was concluded from the electronic absorption spectra and magnetic susceptibility measurements of the complexes. Investigation of the significant infrared bands of the active groups in the ligand and the solid complexes alludes that HL is coordinated to the metal ions ONO tridentate manner. Moreover, the absorption and emission properties of the azo-azomethine based ligand and its complexes were investigated. The results obtained show that fluorescence emissions of the ligand and its metal (II) complexes depend on the type of transition metal ions and the derivatives displayed moderate Stokes' shift values between 44 and 107 nm. All the compounds exhibited superb photostability. Further, antioxidant, antimicrobial and pBR322 plasmid DNA cleavage activities were investigated. All compounds showed good DPPH• (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity and complexes of [MnL2]•H2O and [NiL2]•H2O exhibited excellent metal chelating activity. All the compounds tested demonstrated two strand DNA cleavage activities.

Transition metal(II) complexes of a novel symmetrical benzothiazole-based ligand: synthesis, spectral/structural characterization and fluorescence properties.

2,6-bis (benzothiazol-2-yl)-4-(tert-butyl) phenol ligand (HL) derived from o-aminothiophenol and 4-tert-butyl-2,6-diformylphenol was synthesized and characterized by using elemental analysis, FTIR, X-ray crystallographic analysis, (1)H and (13)C-NMR and UV-vis spectra. Its complexes with Cu (II), Ni (II) and Co (II) were prepared and isolated as solid products and characterized by elemental analysis, spectral techniques as well as magnetic susceptibility. The FTIR spectra showed that the benzothiazole-based ligand under investigation behaves as a bidentate ligand. The UV-vis spectra and magnetic moment data suggested an octahedral geometry around Ni (II) and Co (II) complexes, and tetragonal geometry for Cu (II) complex. Moreover, the evaluation of absorption and emission properties of the ligand and its complexes were carried out in different solvents. The ligand and its complexes showed absorption maxima in the range of 275 - 432 nm, and emission maxima from 367 to 581 nm in toluene, tetrahydrofuran and ethyl acetate.

Fluorescence Properties and Electrochemical Behavior of Some Schiff Bases Derived from N-Aminopyrimidine.

A series of Schiff bases (L 1 , L 2 and L 3) were prepared by refluxing aromatic aldehydes with N-Aminopyrimidine derivatives in methanol and ethanol. The structures of synthesized compounds were characterized by FTIR, (1)H NMR, (13)C NMR and microanalysis. The electrochemical behaviors of the Schiff base ligands were also discussed. Moreover, the evaluation of absorption and emission properties of the structures were carried out in five different solvents. The products show visible absorption maxima in the range of 304-576 nm, and emission maxima from 636 to 736 nm in all solvents tested.

Determination of vanillin in commercial food product by adsorptive stripping voltammetry using a boron-doped diamond electrode.

A method for the determination of food additive vanillin was developed by adsorptive stripping voltammetry. Its determination was carried out at the anodically pre-treated boron-doped diamond electrode in aqueous solutions. Using square-wave stripping mode, the compound yielded a well-defined voltammetric response in phosphate buffer, pH 2.5 at +1.14 V (vs. Ag/AgCl) (a pre-concentration step being carried out at open-circuit condition for 60s). A linear calibration graph was obtained in the concentration range of 0.5-15.0 µg mL(-1) (3.3×10(-6)-9.8×10(-5) mol L(-1)) with a detection limit of 0.024 µg mL(-1) (1.6×10(-7) mol L(-1)). As an example, the practical applicability of the proposed method was tested for the determination of this flavouring agent in commercial pudding powder of Keshkule (Turkish milk pudding with almond flour).

Mean platelet volume is increased in patients with deep vein thrombosis.

BACKGROUND: Pulmonary thromboembolism is a serious complication in patients with deep vein thrombosis (DVT). Previous studies have demonstrated that platelet activation occurs in patients with DVT. Mean platelet volume (MPV) is a simple and easy method of assessing platelet function. The aim of this study was to assess the MPV, an indicator of platelet activation in patients with DVT. PATIENTS AND METHODS: The study group consisted of 52 patients with newly diagnosed acute DVT. An age-, gender-, and body mass index-matched control group consisted of 30 healthy volunteers. All patients and control participants underwent ultrasonographic examination. We measured the serum MPV values in patients with DVT and control participants. RESULTS: Mean platelet volume was significantly higher among patients with DVT when compared with the control group (8.6 ± 0.8 vs 7.7 ± 0.9 fL, respectively; P < .001). CONCLUSION: We have shown that MPV was significantly elevated in patients with DVT compared to controls.

Increased neopterin levels and its association with angiographic variables in patients with slow coronary flow: an observational study.

OBJECTIVE: Although various inflammatory markers have been studied in patients with slow coronary flow (SCF), serum neopterin levels have not been studied previously. We investigated the serum neopterin and high sensitivity C-reactive protein (hs-CRP) levels and the relationship between neopterin and hs-CRP levels and TIMI flow in patients with SCF. METHODS: The study group consisted of 51 patients with SCF. An age and gender matched control group was composed of 40 subjects. Coronary flow rates of all patients and control subjects were documented by Thrombolysis in Myocardial Infarction (TIMI) frame count. We measured serum neopterin and hs-CRP levels at the same time in patients with SCF and control subjects in this cross-sectional observational study. Chi-square, Mann-Whitney U and unpaired t tests, Pearson correlation and linear regression analyses were used for statistical analysis. RESULTS: The TIMI frame counts for all coronary arteries and the mean TIMI frame count were significantly higher in the SCF group than controls. Serum neopterin levels were significantly higher among patients with SCF when compared with control group (2.13±1.03 vs. 1.60±0.50 ng/ml; p=0.004). Serum hs-CRP levels were significantly higher among patients with SCF when compared with control group (2.06±1.32 vs. 0.74±0.40 mg/L respectively; p<0.001). There was a significant association of serum neopterin levels (ß=0.60, 95% CI: 4.93-9.06, p<0.001) and serum hs-CRP levels (ß=0.29, 95%CI: 0.84-4.33, p=0.004) with mean TIMI frame count independent of potential confounders such as age, gender, body mass index, smoking, glucose and cholesterol levels. CONCLUSION: We have shown that serum neopterin and hs-CRP levels were significantly elevated in patients with SCF when compared with control subjects. Serum neopterin and hs-CRP levels were correlated with mean TIMI frame count in patients with SCF.