Beyond Density: Unveiling the Trade-Off in Catalytic Site Optimization Using Defect-Engineered UiO-66.

Enhancing intrinsic activity and increasing catalytic site density are two widely employed strategies to improve catalytic performance. Although typically considered independently, their interplay remains poorly understood. Here, two UiO-66 metal-organic frameworks (MOFs) with distinct catalytic site densities-linker-defective UiO-66L and cluster-defective UiO-66C-are synthesized and systematically compared.

Sulfur Conversion to Donor-Acceptor Ladder Polymer Networks through Mechanochemical Nucleophilic Aromatic Substitution for Efficient CO Photoreduction.

The development of synthetic methods capable of converting elemental sulfur into conjugated porous sulfur-rich polymers remains a great challenge, although direct utilization of this readily available feedstock can significantly enrich its uses and circumvent environmental problems during sulfur storage. We report herein mechanochemical (MC) nucleophilic aromatic substitution (SAr) that enables sulfur conversion into thianthrene-bridged porous ladder polymer networks with dense donor-acceptor (D-A) molecular junctions. We demonstrate that the key lies in the generation of bent thianthrene units through a solid-state ball-milling condensation reaction between 1,2-dihaloarenes and elemental sulfur.

A Cosolvent Electrolyte Boosting Electrochemical Alkynol Semihydrogenation.

Green electricity-driven alkenol electrosynthesis via electrocatalytic alkynol semihydrogenation represents a sustainable route to conventional thermocatalysis. Both the electrocatalyst and electrolyte strongly impact the semihydrogenation performance. Despite significant progress in developing sophisticated electrocatalysts, a well-designed electrolyte in conjunction with industrial catalysts is an attractive strategy to advance the industrialization process of electrocatalytic alkynol semihydrogenation, but remains unexplored.

Can Subsurface Oxygen Species in Oxides Participate in Catalytic Reactions? An O Solid-State Nuclear Magnetic Resonance Study.

The impacts of subsurface species of catalysts on reaction processes are still under debate, largely due to a lack of characterization methods for distinguishing these species from the surface species and the bulk. By using O solid-state nuclear magnetic resonance (NMR) spectroscopy, which can distinguish subsurface oxygen ions in CeO (111) nanorods, we explore the effects of subsurface species of oxides in CO oxidation reactions. The intensities of the O NMR signals due to surface and subsurface oxygen ions decrease after the introduction of CO into CeO nanorods, with a more significant decrease observed for the latter, confirming the participation of subsurface oxygen species.

Delocalized Orbitals over Metal Clusters and Organic Linkers Enable Boosted Charge Transfer in Metal-Organic Framework for Overall CO Photoreduction.

The conversion of CO to C through photocatalysis poses significant challenges, and one of the biggest hurdles stems from the sluggishness of the multi-electron transfer process. Herein, taking metal-organic framework (MOF, PFC-98) as a model photocatalyst, we report a new strategy to facilitate charge separation. This strategy involves matching the energy levels of the lowest unoccupied node and linker orbitals of the MOF, thereby creating the lowest unoccupied crystal orbital (LUCO) delocalized over both the node and linker.

Dynamic Evolution and Reversibility of a Single Au Nanocluster for the Oxygen Reduction Reaction.

Ultrasmall metallic nanoclusters (NCs) protected by surface ligands represent the most promising catalytic materials; yet understanding the structure and catalytic activity of these NCs remains a challenge due to dynamic evolution of their active sites under reaction conditions. Herein, we employed a single-nanoparticle collision electrochemistry method for real-time monitoring of the dynamic electrocatalytic activity of a single fully ligand-protected Au(PPh)(SCHPh)Cl nanocluster (Au NC) at a cavity carbon nanoelectrode toward the oxygen reduction reaction (ORR). Our experimental results and computational simulations indicated that the reversible depassivation and passivation of ligands on the surface of the Au NC, combined with the dynamic conformation evolution of the Au core, led to a characteristic current signal that involves "ON-OFF" switches and "ON" fluctuations during the ORR process of a single Au NC.

Highly Selective Photocatalytic Synthesis of Acetic Acid at 0-25 °C.

Acetic acid (AA), a vital compound in chemical production and materials manufacturing, is conventionally synthesized by starting with coal or methane through multiple steps including high-temperature transformations. Here we present a new synthesis of AA from ethane through photocatalytic selective oxidation of ethane by HO at 0-25 °C. The catalyst designed for this process comprises g-CN with anchored Pd single-atom sites.

Synthetic Leaves Based on Crystalline Olefin-Linked Covalent Organic Frameworks for Efficient CO Photoreduction with Water.

We report, for the first time, a new synthetic strategy for the preparation of crystalline two-dimensional olefin-linked covalent organic frameworks (COFs) based on aldol condensation between benzodifurandione and aromatic aldehydes. Olefin-linked COFs can be facilely crystallized through either a pyridine-promoted solvothermal process or a benzoic anhydride-mediated organic flux synthesis. The resultant COF leaf with high in-plane π-conjugation exhibits efficient visible-light-driven photoreduction of carbon dioxide (CO) with water (HO) in the absence of any photosensitizer, sacrificial agents, or cocatalysts.

: A program for combined quantum mechanical and molecular mechanical modeling and simulations.

Combined quantum mechanical and molecular mechanical (QM/MM) methods play an important role in multiscale modeling and simulations. is a general-purpose program for single-point calculations, geometry optimizations, transition state optimizations, and molecular dynamics (MD) at the QM/MM level. It calls a QM package and an MM package to perform the required single-level calculations and combines them into a QM/MM energy by a variety of schemes.

Level-Shifted Embedded Cluster Method for Modeling the Chemistry of Metal Oxides.

The embedded cluster method has been used extensively in the study of the chemical and physical properties of metal oxides. This method has been a popular tool due to its relatively high accuracy and low computational cost. An even more promising option may entail integrating the embedded cluster method with the combined quantum mechanical and molecular mechanical (QM/MM) approach, thereby enabling further consideration of interactions within the entire system for superior results.

Photo-Induced Active Lewis Acid-Base Pairs in a Metal-Organic Framework for H Activation.

The establishment of active sites as the frustrated Lewis pair (FLP) has recently attracted much attention ranging from homogeneous to heterogeneous systems in the field of catalysis. Their unquenched reactivity of Lewis acid and base pairs in close proximity that are unable to form stable adducts has been shown to activate small molecules such as dihydrogen heterolytically. Herein, we show that grafted Ru metal-organic framework-based catalysts prepared via N-containing linkers are rather catalytically inactive for H activation despite the application of elevated temperatures.

A comprehensive study on flocculation of anionic dyes using the bioflocculant produced by Bacillus thuringiensis: Kinetics, affecting factors, and perspectives.

Bioflocculants have received more and more attention as alternatives to chemical flocculants because of their innocuousness, environmental friendliness, and high effectiveness. This study aims to investigate various factors that influence the performance of the novel bioflocculant produced by Bacillus thuringiensis (BF-TWB10) and analyze its adsorption kinetics to optimize its flocculation performance for real applications. The best-fit kinetic model was pseudo-second order with R  = 0.

Uncovering Structure-Activity Relationships in Pt/CeO Catalysts for Hydrogen-Borrowing Amination.

The hydrogen-borrowing amination of alcohols is a promising route to produce amines. In this study, experimental parameters involved in the preparation of Pt/CeO catalysts were varied to assess how physicochemical properties influence their performance in such reactions. An amination reaction between cyclopentanol and cyclopentylamine was used as the model reaction for this study.

Exceptional Hydrogen Diffusion Rate over Ru Nanoparticle-Doped Polar MgO(111) Surface.

Hydrogen (H) conductivity on oxide-based materials is crucially important in fuel cells and related catalysis. Here, this work measures the diffusion rate of H generated from Ru nanoparticles loaded on polar MgO(111) facet particles under H at elevated temperatures without moisture and compares it to conventional nonpolar MgO(110) for the first time by in situ quasielastic neutron scattering (QENS). The QENS reveals an exceptional diffusion rate on the polar facet via a proton (H ) hopping mechanism, which is an order of magnitude superior to that of typical H -conducting oxides.

Unveiling the Surface Structure of ZnO Nanorods and H Activation Mechanisms with O NMR Spectroscopy.

ZnO plays a very important role in many catalytic processes involving H, yet the details on their interactions and H activation mechanism are still missing, owing to the lack of a characterization method that provides resolution at the atomic scale and follows the fate of oxide surface species. Here, we apply O solid-state NMR spectroscopy in combination with DFT calculations to unravel the surface structure of ZnO nanorods and explore the H activation process. We show that six different types of oxygen ions in the surface and subsurface of ZnO can be distinguished.

Curcumin combined with arsenic trioxide in the treatment of acute myeloid leukemia: network pharmacology analysis and experimental validation.

Purpose: This study aimed to evaluate the effects of curcumin by co-administration of arsenic trioxide (AsO) in acute myeloid leukemia (AML) treatment, using network pharmacology and experimental validation.

Methods: Using Pubchem database, Traditional Chinese Medicine Information Database (TCMID) database, and Swiss target prediction database to predict compound-related targets, AML-associated targets were determined using GeneCards and Online Mendelian Inheritance in Man (OMIM) databases. We identify overlapping common targets by comparing Compounds-related and AML-associated targets and using these targets to perform GO and KEGG functional enrichment analyses.

Surface differences of oxide nanocrystals determined by geometry and exogenously coordinated water molecules.

Determining the different surfaces of oxide nanocrystals is key in developing structure-property relations. In many cases, only surface geometry is considered while ignoring the influence of surroundings, such as ubiquitous water on the surface. Here we apply O solid-state NMR spectroscopy to explore the facet differences of morphology-controlled ceria nanocrystals considering both geometry and water adsorption.

[Antibiotic use in very low birth weight/extremely low birth weight infants in 15 hospitals in Jiangsu Province of China: a multicenter survey].

Objectives: To investigate the current status of antibiotic use in very low birth weight/extremely low birth weight infants in Jiangsu Province of China, and to provide a clinical basis for the quality and improvement of antibiotic management in the neonatal intensive care unit (NICU).

Methods: A retrospective analysis was performed on the data on general conditions and antibiotic use in the very low birth weight/extremely low birth weight infants who were admitted to 15 hospitals of Jiangsu Province from January 1, 2019 to December 31, 2020. A questionnaire containing 10 measures to reduce antibiotic use was designed to investigate the implementation of these intervention measures.

A comparison of DP-TOF Mass Spectroscopy (MS) and Next Generation Sequencing (NGS) methods for detecting molecular mutations in thyroid nodules fine needle aspiration biopsies.

Mutations in the B-Raf proto-oncogene, serine/threonine kinase (BRAF), have been linked to a variety of solid tumors such as papillary thyroid carcinoma. The purpose of this study was to compare the DP-TOF, a DNA mass spectroscopy (MS) platform, and next-generation sequencing (NGS) methods for detecting multiple-gene mutations (including BRAF) in thyroid nodule fine-needle aspiration fluid. In this study, we collected samples from 93 patients who had previously undergone NGS detection and had sufficient DNA samples remaining.

[Preadmission follow-up condition of neonates hospitalized due to severe hyperbilirubinemia after discharge from the department of obstetrics and influencing factors for follow-up compliance: a multicenter investigation].

Objectives: To investigate the preadmission follow-up condition of neonates hospitalized due to severe hyperbilirubinemia after discharge from the department of obstetrics and the influencing factors for follow-up compliance.

Methods: A multicenter retrospective case-control study was performed for the cases from the multicenter clinical database of 12 units in the Quality Improvement Clinical Research Cooperative Group of Neonatal Severe Hyperbilirubinemia in Jiangsu Province of China from January 2019 to April 2021. According to whether the follow-up of neonatal jaundice was conducted on time after discharge from the department of obstetrics, the neonates were divided into two groups: good follow-up compliance and poor follow-up compliance.

Unique catalytic mechanisms of methanol dehydrogenation at Pd-doped ceria: A DFT+U study.

Pd-doped ceria is highly active in promoting oxidative dehydrogenation (ODH) reactions and also a model single atom catalyst (SAC). By performing density functional theory calculations corrected by on-site Coulomb interactions, we systematically studied the physicochemical properties of the Pd-doped CeO(111) surface and the catalytic methanol to formaldehyde reaction on the surface. Two different configurations were located for the Pd dopant, and the calculated results showed that doping of Pd will make the surface more active with lower oxygen vacancy formation energies than the pristine CeO(111).

Clinical effect of different maintenance doses of caffeine citrate in the treatment of preterm infants requiring assisted ventilation: a pilot multicenter study.

Objectives: To explore the optimal maintenance dose of caffeine citrate for preterm infants requiring assisted ventilation and caffeine citrate treatment.

Methods: A retrospective analysis was performed on the medical data of 566 preterm infants (gestational age ≤34 weeks) who were treated and required assisted ventilation and caffeine citrate treatment in the neonatal intensive care unit of 30 tertiary hospitals in Jiangsu Province of China between January 1 and December 31, 2019. The 405 preterm infants receiving high-dose (10 mg/kg per day) caffeine citrate after a loading dose of 20 mg/kg within 24 hours after birth were enrolled as the high-dose group.

Synthesis of α-Aryl Primary Amides from α-Silyl Nitriles and Aryl Sulfoxides through [3,3]-Sigmatropic Rearrangement.

A simple and efficient protocol was developed for the preparation of challenging α-aryl primary amides. This metal-free coupling process was triggered by TfOH-promoted electrophilic activation of α-silyl nitrile to generate keteniminium ion species, followed by reaction with aryl sulfoxide through [3,3]-sigmatrophic rearrangement to provide the target product. To the best of our knowledge, α-silyl nitrile has been rarely used as a pro-electrophilic reagent.

Identification of CO adsorption sites on MgO nanosheets by solid-state nuclear magnetic resonance spectroscopy.

The detailed information on the surface structure and binding sites of oxide nanomaterials is crucial to understand the adsorption and catalytic processes and thus the key to develop better materials for related applications. However, experimental methods to reveal this information remain scarce. Here we show that O solid-state nuclear magnetic resonance (NMR) spectroscopy can be used to identify specific surface sites active for CO adsorption on MgO nanosheets.

Effects of Qinghuang Powder on Acute Myeloid Leukemia Based on Network Pharmacology, Molecular Docking, and In Vitro Experiments.

Qinghuang powder (QHP) is a traditional Chinese herbal medicine. This is a unique formula that is frequently used to treat malignant hematological diseases such as acute myeloid leukemia (AML) in modern clinical practice. An approach of network pharmacology and experimental validation were applied to investigate the pharmacological mechanisms of QHP in AML treatment.