A Zeolitic Octahedral Metal Oxide with Ultrahigh Porosity for High-temperature and High-humidity Alkyne/Alkene Separation.

Zeolitic octahedral metal oxide is a newly synthesized all-inorganic zeolitic material and has been used for adsorption, separation, and catalysis. Herein, a new zeolitic octahedral metal oxide was synthesized and characterized. The porous framework was established through the assembly of [P2Mo13O50] clusters with PO4 linkers. Guest molecules occupied the framework, which could be removed through heat treatment, thereby opening the micropores. The pore characteristics were controlled by the cations within the micropore, enabling the adjustment of the interactions with alkynes and alkenes. This resulted in good separation performance of ethylene/acetylene and propylene/propyne even under high temperature and humidity conditions. The high stability of the material enabled the efficient recovery and reuse without discernible loss in the separation performance. Due to the relatively weak interaction between the adsorbed alkyne and the framework, the adsorbent facilitated the recovery of a highly pure alkyne. This feature enhances the practical applicability of the material in various industrial processes.

A Zeolitic Octahedral Metal Oxide with Ultra-Microporosity for Inverse CO2 /C2 H2 Separation at High Temperature and Humidity.

Separation of CO2 /C2 H2 to obtain pure C2 H2 presents a challenge for the chemical industry. CO2 -selective adsorbents are favored because of the convenient separation process. However, there are only a few CO2 -selective adsorbents that can effectively isolate CO2 from CO2 /C2 H2 , and there is almost no research on CO2 /C2 H2 separation under harsh conditions, such as with high temperatures and humidities. Herein, a zeolitic octahedral metal oxide based on ϵ-Keggin polyoxometalates is utilized for separations of CO2 /C2 H2 at high temperatures and humidities. Single gas adsorption measurements show that the material only adsorbs CO2 with almost no C2 H2 taken up. Dynamic competitive adsorption experiments show that the material efficiently separates CO2 /C2 H2 , and highly pure C2 H2 is obtained directly. The robust material maintains a high separation performance at 333 K with 18.12 % water. The high stability of the material enables reuse without loss of separation performance.

Single-Atom-Thick Active Layers Realized in Nanolaminated Ti3(AlxCu1-x)C2 and Its Artificial Enzyme Behavior.

A Ti3(AlxCu1-x)C2 phase with Cu atoms with a degree of ordering in the A plane is synthesized through the A site replacement reaction in CuCl2 molten salt. The weakly bonded single-atom-thick Cu layers in a Ti3(AlxCu1-x)C2 MAX phase provide actives sites for catalysis chemistry. As-synthesized Ti3(AlxCu1-x)C2 presents unusual peroxidase-like catalytic activity similar to that of natural enzymes. A fabricated Ti3(AlxCu1-x)C2/chitosan/glassy carbon electrode biosensor prototype also exhibits a low detection limit in the electrochemical sensing of H2O2. These results have broad implications for property tailoring in a nanolaminated MAX phase by replacing the A site with late transition elements.

Direct, selective and ultrasensitive electrochemical biosensing of methyl parathion in vegetables using Burkholderia cepacia lipase@MOF nanofibers-based biosensor.

Methyl parathion is one of the most widely used pesticides in agricultural practices. It caused accumulation of acetylcholine and over-stimulation of receptors in synapses which eventually led to damage of the nervous system. Present study developed a direct, sensitive, rapid and reliable method for methyl parathion residues detection in vegetable samples. MOF nanofibers which demonstrated stable framework structure, good thermal/chemical stability, good electrochemical behavior, high porosity, surface area and pore volume was synthesized and used for fabrication of Burkholderia cepacia lipase (BCL)@MOF nanofibers biosensors. BCL@MOF nanofibers/chitosan/GCE biosensor demonstrated high sensitivity for methyl detection with a wide linear range (0.1-38 µM) and low limit of detection 0.067 µM. During the 3 weeks storage stability test at 4 °C, the fabricated biosensor demonstrated good reusability and excellent stability for methyl parathion detection with retainment of more than 80% of its initial response. When applied for detection of methyl parathion residues in vegetable samples, the BCL@MOF nanofibers/chitosan/GCE biosensors demonstrated good recovery rates.

Fingerprinting of Phospholipid Molecular Species from Human Milk and Infant Formula Using HILIC-ESI-IT-TOF-MS and Discriminatory Analysis by Principal Component Analysis.

Phospholipid composition in the milk fat globule membrane (MFGM) fluctuates during the entire lactation period in order to suit the growing needs of newborn infants. The present study elucidated and relatively quantified phospholipid molecular species extracted from human milk (HM), mature human milk (MHM), and infant formulas (with or without MFGM supplementation) using hydrophilic liquid chromatography-electrospray ionization-ion trap-time of flight-mass spectrometry (HILIC-ESI-IT-TOF-MS) system. Principal component analysis was used to clarify the differences between phospholipid composition in HM, MHM, and infant formulas. HM and MHM contained high concentrations of sphingomyeline (HM: 107.61 µg/mL, MHM: 227.18 µg/mL), phosphatidylcholine (HM: 59.96 µg/mL, MHM: 50.77 µg/mL), and phosphatidylethanolamine (PE) (HM: 25.24 µg/mL, MHM: 31.76 µg/mL). Significant concentrations (<300 ng/mL) of arachidonic, eicosapentanoic, and docosahexanoic acids were found to esterify to PE in HM and MHM. Meanwhile, all infant formulas were found to contain high concentrations of phosphatidic acids indicating the possibility of degradation of the fortified MFGM either during processing or storage of the infant formulas.