Efficient One‐pot Zeolite Synthesis Protocol from the Metastable *BEA to MTW Topology and Its Impact on the Methanol‐to‐Hydrocarbons Process

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Efficient One-pot Zeolite Synthesis Protocol from the Metastable *BEA to MTW Topology and Its Impact on the Methanol-to-Hydrocarbons Process

The “one-pot” inter-zeolite conversion process has been probed during the transformation from *BEA to MTW topology, which was subjected to methanol-to-hydrocarbons reactions and advanced characterization (including operando conditions) to derive structure-reactivity relationships.


Abstract

The inter-zeolite conversion is a method to convert one meta-stable zeolite to a thermodynamically stable zeolite. Despite the enormous interest, this method is yet to be popularized or standardized in the zeolite community. Intending to provide more insights into hydrothermal conversions from one zeolite to another, this work developed a novel one-pot and flexible synthetic protocol to efficiently obtain the meta-stable *BEA topology and its derived MTW topology by varying the hydrothermal crystallization time. This inter-zeolite conversion process led to changes in the zeolite framework and modified physicochemical properties during the process. Such a transformation was feasible by forming hierarchical zeolite phases sharing a similar “mtw”-based common building units, possibly driving such conversion. The structure-reactivity relationship of four different zeolite materials, synthesized from this one-pot inter-zeolite conversion method, was established concerning their performance in the methanol-to-hydrocarbon (MTH) process, which has been well supported by operando UV-vis diffuse reflectance spectroscopic study coupled with online mass spectrometry and solid-state NMR spectroscopy. As a result, the pathway to synthesize various target zeolites from an identical initial synthesis gel with desired physicochemical properties has been scrutinized.

Vanadium(IV)‐oxo Corrole Catalyzed Selective Oxidative Cleavage of Alkenes to Aldehydes

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Vanadium(IV)-oxo Corrole Catalyzed Selective Oxidative Cleavage of Alkenes to Aldehydes

An oxo[5,10,15-tris(4-nitrophenyl)corrolato]vanadium (IV) complex (cat.), has been successfully synthesized and the existence of two tautomeric forms of this complex in solution has been established. Oxo[5,10,15-tris(4 nitrophenyl)corrolato]vanadium (IV) (cat.) in the presence of H2O2 cleaves olefinic bonds to yield the corresponding aldehyde compounds. A mechanism was also proposed for these catalysis reactions.


Abstract

A practical and efficient protocol for oxidative cleavage of olefinic bonds especially in arylated olefins has been demonstrated. Herein, an oxo[5,10,15-tris(4-nitrophenyl)corrolato]vanadium (IV) complex (cat.), has been successfully synthesized and the existence of two tautomeric forms of this complex in solution has been established. Oxo[5,10,15-tris(4-nitrophenyl)corrolato]vanadium (IV) (cat.) in the presence of H2O2 cleaves olefinic bonds to yield the corresponding aldehyde compounds. In general, a high valent, oxo-(porphyrinoid)-metal complex catalyzes the epoxide formation reactions, however, in the present case, we have observed the exclusive formation of aldehydes. The reaction offered aryl aldehydes with good yields and excellent selectivity. A mechanism was also proposed for these catalysis reactions.

Iron‐Based Nanoparticles Oxygen Scavenger for Suppressing Heat‐Stable Salts Formation in Amine

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Iron-Based Nanoparticles Oxygen Scavenger for Suppressing Heat-Stable Salts Formation in Amine

The correlation of physicochemical properties of iron-based nanoparticles with their activity in oxygen-scavenging was developed. The addition of a 20 %Fe/HZSM5 oxygen scavenger to methyl diethanolamine (MDEA) did not jeopardize the CO2 absorption performance but inhibited the MDEA degradation. The absence of the degraded products prevented the formation of heat-stable salts that cause foaming issues.


Abstract

Heat-stable salts (HSS), which trigger excessing foaming in absorber, are formed when protonated methyl diethanolamine (MDEA) reacts with the more acidic degraded products in the presence of dissolved oxygen (DO). The aim is to suppress the HSS formation in MDEA solution inaugurally employing a hybrid iron-based nanoparticles (HINP) oxygen scavenger. It was discovered that the oxygen-scavenging performance of a more cost-effective 20 %Fe/HZSM5 was one-fold higher than the 20 %Fe/MCM-41. The former was verified for its superior structural properties. The Fe2+ on its surface first reacted with DO, preventing DO from oxidizing the MDEA. Consequently, the absence of hydroxyl radicals eliminated the potential of formic acid formation, hence suppressing the MDEA-acid HSS formation.

Comprehensive Phytochemical Content by LC/MS/MS and Anticholinergic, Antiglaucoma, Antiepilepsy, and Antioxidant Activity of Apilarnil (Drone Larvae)

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Comprehensive Phytochemical Content by LC/MS/MS and Anticholinergic, Antiglaucoma, Antiepilepsy, and Antioxidant Activity of Apilarnil (Drone Larvae)


Abstract

Apilarnil is 3–7 days old drone larvae. It is an organic bee product known to be rich in protein. In this study, the biological activities of Apilarnil were determined by its antioxidant and enzyme inhibition effects. Antioxidant activities were determined by Fe3+, Cu2+, Fe3+-TPTZ ((2,4,6-tris(2-pyridyl)-s-triazine), reducing ability and 1,1-diphenyl-2-picrylhydrazyl (DPPH⋅) scavenging assays. Also, its enzyme inhibition effects were tested against carbonic anhydrase I and II isoenzymes (hCA I, hCA II), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Antioxidant activity of Apilarnil was generally lower than the standard molecules in the applied methods. In DPPH⋅ radical scavenging assay, Apilarnil exhibited higher radical scavenging than some standards. Enzyme inhibition results towards hCA I (IC50: 14.2 μg/mL), hCA II: (IC50: 11.5 μg/mL), AChE (IC50: 22.1 μg/mL), BChE (IC50: 16.1 μg/mL) were calculated. In addition, the quantity of 53 different phytochemical compounds of Apilarnil was determined by a validated method by LC/MS/MS. Compounds with the highest concentrations (mg analyte/g dry extract) were determined as quinic acid (1091.045), fumaric acid (48.714), aconitic acid (47.218), kaempferol (39.946), and quercetin (27.508). As a result, it was determined that Apilarnil had effective antioxidant profile when compared to standard antioxidants.

Chiral Substitution on Spaced Cations Lead to Improved Properties and Reversible Phase Transition, Broadband Emission in Parent Compound (3APr)PbBr4

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Chiral Substitution on Spaced Cations Lead to Improved Properties and Reversible Phase Transition, Broadband Emission in Parent Compound (3APr)PbBr4

We report a multifunctional compound: (3APr)PbBr4 (1) (3APr=3-Pyrrolidinamine) and corresponding enantiomer R and S-(3APr)PbBr4 (R/S-2). Compound 1 show reversible solid-state phase transition, step-like dielectric anomaly and broadband yellow emission under ultraviolet light excitation. the R/S-2 display mirror image structural relationship, increases quantum yield and CD signal.


Abstract

Hybrid organic-inorganic perovskites (HOIP) due to their excellent optoelectronic properties and flexible structure have attracted enthusiastic interest. In particular, introducing chirality is a method to enhance compound performance. Herein, we report a multifunctional compound: (3APr)PbBr4 (1) (3APr=3-Pyrrolidinamine) and corresponding enantiomer R and S-(3APr)PbBr4 (R/S-2). Compound 1 show reversible solid-state phase transition, step-like dielectric anomaly and broadband yellow emission under uv light excitation. Accompany with phase transition, structure dimension transition from 2D to 1D without space group change. Through introduce chirality, the R/S-2 display mirror image 1D structural relationship, increased quantum yield from 3.43 % (1) to 13.65 % (R/S-2) and exhibits corresponding CD signals. Then combine to first-principles analysis, it was found that fluorescence is attributed to the formation of instantaneous defects during excitation, leading to the formation of self-trapped excitons (STEs). This finding will further promote the development of multifunctional compound and the study of chiral substitution enhance compound properties.

Comparative Analysis of Antioxidant, Anticholinesterase, and Antibacterial Activity of Microbial Chondroitin Sulfate and Commercial Chondroitin Sulfate

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Comparative Analysis of Antioxidant, Anticholinesterase, and Antibacterial Activity of Microbial Chondroitin Sulfate and Commercial Chondroitin Sulfate


Abstract

Chondroitin synthesis was performed using the recombinant Escherichia coli(C2987) strain created by transforming the plasmid pETM6-PACF-vgb, which carries the genes responsible for chondroitin synthesis, kfoA, kfoC, kfoF, and the Vitreoscilla hemoglobin gene (vgb). Then, Microbial chondroitin sulfate (MCS)’s antioxidant, anticholinesterase, and antibacterial activity were compared with commercial chondroitin sulfate (CCS). The antioxidant studies revealed that the MCS and CCS samples could be potential targets for scavenging radicals and cupric ion reduction. MCS demonstrated better antioxidant properties in the ABTS assay with the IC50 value of 0.66 mg than CCS. MCS showed 2.5-fold for DPPH and almost 5-fold for ABTS⋅+ (with a value of 3.85 mg/mL) better activity than the CCS. However, the compounds were not active for cholinesterase enzyme inhibitions. In the antibacterial assay, the Minimum inhibitory concentration (MIC) values of MCS against S. aureus, E. aerogenes, E. coli, P. aeruginosa, and K. pneumoniae (0.12, 0.18, 0.12, 0.18, and 0.18 g/mL, respectively) were found to be greater than that of CCS (0.42, 0.48, 0.36, 0.36, and 0.36 g/mL, respectively). This study demonstrates that MCS is a potent pharmacological agent due to its physicochemical properties, and its usability as a therapeutic-preventive agent will shed light on future studies.

Genipa americana L.: A New Phytochemical for White Hair Coloring

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Genipa americana L.: A New Phytochemical for White Hair Coloring


Abstract

This work describes a new hair dyeing methodology using a chemical reaction between geniposide, an iridoid glycoside extracted from the fruit of Genipa americana (geniposide extract, GE) and the amine group of hair keratin. The influence of reaction conditions (pH, temperature, and extract concentration) on the staining of hair fibers, color development, fiber morphology, and mechanical hair properties of black and white human hair samples, was evaluated before and after GE dyeing treatment. Eye contact safety of GE was also studied using HET-CAM. The treatment of white hair fibers using GE at 20 mg mL−1, temperature of 80 °C and pH 5.5 presented the greatest color change (ΔE=54.0). The higher pH influence was observed at pH 10.0 on white hair tresses (ΔE=6.8), using an GE concentration of 20 mg mL−1 and room temperature (25 °C). Treated samples showed marked changes on mechanical and morphological properties. The HET-CAM did not show any change, thus demonstrating that using GE is safe. In conclusion, the temperature and concentration of the extract were the variables that mostly influenced the color and hair damage. A new approach for hair dyeing was established where iridoids may potentially be useful as a natural hair dyeing.

Amine‐Functionalized Amyloid Aerogels for CO2 Capture

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Amine-Functionalized Amyloid Aerogels for CO2 Capture

Amyloid fibrils from β-lactoglobulin (BLG), lysozyme, and black bean protein were prepared and modified with aminosilane. Then, the amine-functionalized amyloid fibril-templated aerogels were synthesized to capture CO2 from a dilute atmosphere (~400 ppm CO2).


Abstract

Climate change caused by excessive CO2 emissions constitutes an increasingly dire threat to human life. Reducing CO2 emissions alone may not be sufficient to address this issue, so that the development of emerging adsorbents for the direct capture of CO2 from the air becomes essential. Here, we apply amyloid fibrils derived from different food proteins as the solid adsorbent support and develop aminosilane-modified amyloid fibril-templated aerogels for CO2 capture applications. The results indicate that the CO2 sorption properties of the aerogels depend on the mixing ratio of aminosilane featuring different amine groups and the type of amyloid fibril used. Notably, amine-functionalized β-lactoglobulin (BLG) fibril-templated aerogels show the highest CO2 adsorption capacity of 51.52 mg (1.17 mmol) CO2/g at 1 bar CO2 and 25.5 mg (0.58 mmol) CO2/g at 400 ppm; similarly, the CO2 adsorption capacity of chitosan-BLG fibril hybrid aerogels is superior to that of pure chitosan. This study provides a proof-of-concept design for an amyloid fibril-templated hybrid material facilitating applications of protein-based adsorbents for CO2 capture, including direct air capture.

Hydrogen Evolution of a Unique DNAzyme Composed of Cobalt‐Protoporphyrin IX and G‐Quadruplex DNA

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Molecular hydrogen (H2) is a clean and renewable fuel that has garnered significant interest in the search for alternatives to fossil fuels. Here, we constructed an artificial DNAzyme composed of cobalt-protoporphyrin IX (CoPP) and G-quadruplex DNA, possessing a unique H2Oint ligand between the CoPP and G-quartet planes. We show for the first time that CoPP-DNAzyme catalyzes photo-induced H2 production under anaerobic conditions with a turnover number (TON) of 1229 ± 51 over 12 h at pH 6.05 and 10°C. Compared with free-CoPP, complexation with G-quadruplex DNA resulted in a 4.7-fold increase in H2 production activity. The TON of the CoPP-DNAzyme revealed an optimal acid-base equilibrium with a pKa value of 7.60 ± 0.05, apparently originating from the equilibrium between Co(III)-H– and Co(I) states. Our results demonstrate that the H2Oint ligand can augment and modulate the intrinsic catalytic activity of H2 production catalysts. These systems pave the way to using DNAzymes for H2 evolution in the direct conversion of solar energy to H2 from water.

Calculation of the moscovium ground‐state energy by quantum algorithms

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Calculation of the moscovium ground-state energy by quantum algorithms

The possibility of simulating the electronic structure of ions and atoms by quantum algorithms is studied in the example of the moscovium atom. Among all tested approaches, the variational quantum eigensolver with the problem-inspired ansatz and Adam optimizer demonstrated the highest level of scalability while simultaneously providing a high level of accuracy for the ground-state energy.


Abstract

We investigate the possibility to calculate the ground-state energy of the atomic systems on a quantum computer. For this purpose we evaluate the lowest binding energy of the moscovium atom with the use of the iterative phase estimation and variational quantum eigensolver (VQE). The calculations by the VQE are performed with a disentangled unitary coupled cluster ansatz and with various types of hardware-efficient ansatze. The optimization is performed with the use of the Adam and quantum natural gradients procedures. The scalability of the ansatze and optimizers is tested by increasing the size of the basis set and the number of active electrons. The number of gates required for the iterative phase estimation and VQE is also estimated.