The oxygen evolution reaction on cobalt atom embedded nitrogen doped graphene electrocatalysts: a density functional theory study.

The oxygen evolution reaction (OER) is essential for the development of renewable energy conversion and storage technologies. Eight N-doped graphenes containing variable numbers of embedded cobalt atoms (Coxy-NG, x = 1-4, y = 1-3, where x represents the number of embedded Co atoms and y represents different configurations) were designed and their OER electrocatalytic activities were systematically studied through density functional theory calculations. The significant roles of the number of Co atoms and their configuration in their OER performance were discussed in detail. Co31-NG occupies the peak of the activity volcano plot with a low overpotential of 0.31 V, which is smaller than Co11-NG with only one Co atom and even superior to the widely used IrO2 (0.56 V). The electronic structure and electron density analysis reveal that the outstanding electrocatalytic performance is due to the orbital hybridization between Co and N atoms and the increased positive charge on in-plane Co due to the out-of-plane Co atoms/clusters. This work clarifies the important role of transition atoms and provides excellent examples for reducing the overpotential through embedding several transition metal atoms onto single-atom electrocatalysts.

Brassisterol A, a new ergosterol from co-cultivation of fungi attenuates neuroinflammation via targeting NLRP3/caspase-1/GSDMD pathway.

Three new ergosterol derivatives brassisterol A-C (1-3) and two new epimeric bicycle-lactones brassictones A and B (4 and 5), were isolated from the co-cultivation of Alternaria brassicicola and Penicillium granulatum. The absolute configurations of these isolates were confirmed by extensive NMR spectra, TD-DFT ECD calculation, and the single crystal XRD data analysis. Amongst the metabolites, compound 1 exhibited potential anti-Parkinson's disease activity in both MPTP-induced zebrafish and MPP+-induced SH-SY5Y cells. Molecular mechanism studies in vitro showed that 1 attenuated the increase of α-synuclein, NLRP3, ASC, caspase-1, IL-1ß, IL-18, and GSDMD expression in the MPP+ induced PD model. Molecular docking in silico simulations exhibited that 1 was well accommodated to one of the binding pockets of NLRP3 8ETR in an appropriate conformation via forming typical hydrogen bonds as well as possessing a high negative binding affinity (-8.97 kcal/mol). Thus, our work suggested that 1 protected dopaminergic cell from neuroinflammation via targeting NLRP3/caspase-1/GSDMD signaling pathway.

Tuning the Photophysical Properties of Acceptor-Donor-Acceptor Di-2-(2-oxindolin-3-ylidene) Malononitrile Materials via Extended π-Conjugation: A Joint Experimental and Theoretical Study.

Many optoelectronic applications require organic semiconductor (OSC) materials with high electron affinity. In this work, a series of novel acceptor-donor-acceptor (A-D-A) materials with low-lying LUMO energy levels were designed and characterized. In this strategy, two acceptor dyes, bis-isatin and di-2-(2-oxindolin-3-ylidene) malononitrile, were connected by various π-bridges (benzene ring, benzo[c][1,2,5]thiadiazole, monothiophene, trithiophene). We varied the length of the π-conjugation of the central core and the linkage position of the acceptor core (4- vs. 6-position of the phenyl ring) to investigate the effect on the optical and electrochemical properties of the materials. We performed density functional theory (DFT) and time-dependent DFT (TD-DFT) studies to gain insight into the dyes' electronic properties by determining the energy levels. Our findings demonstrate that with increasing acceptor strength and π-conjugation length of the core, the wavelength of the longest absorption maximum as well as their respective extinction coefficients are enhanced, which results in band-gap reduction either by lowering the LUMO and/or raising the HOMO energy level of the molecules. The potential practical utility of these materials as electron-transport materials for perovskite solar cells (PSCs) has been demonstrated.

Metalloporphyrin-Based Metal-Organic Frameworks for the Ultrasensitive Chemiresistive Detection of NO2: Effect of the Central Metal on Tuning the Sensing Performance.

The highly sensitive and selective detection of trace hazardous gases at room temperature is very promising for health protection and environmental safety. Herein, chemiresistive sensors for NO2 were fabricated based on self-assembled films of the four metalloporphyrin (MPor)-based metal-organic frameworks PCN-222-M (M = Cu, Ni, Co, Fe) by the quasi-Langmuir-Shäfer method. It is found that the relative responses of the four PCN-222-M films are linearly related to the NO2 concentration, and the PCN-222-Cu possessed an unprecedented high response to NO2 with a sensitivity of 2209% ppm-1 in the 4-20 ppb range and a low limit of detection (LOD) of 0.93 ppb, achieving the best performance reported so far for NO2 detection at room temperature. Meanwhile, PCN-222-Ni showed the fastest recovery among the four PCN-222-M films, which can be used for the rapid detection of NO2. Excellent reproducibility, stability, selectivity, and moisture resistance are shown for both PCN-222-Cu and PCN-222-Ni. Combining the experimental study and density functional theory (DFT) calculation, the essential roles of MPor units and the MPor/Zr6 cluster hybrid material in tuning the Fermi level and the electron transfer between PCN-222-M and NO2 were further proved. These were less considered topics in previous studies on MOFs. This work explores the application of MPor-based MOFs in gas sensing by selecting appropriate MPor units, thus providing guidance for the development of MOF-based chemiresistive sensors.

Fractal Design of Hierarchical PtPd with Enhanced Exposed Surface Atoms for Highly Catalytic Activity and Stability.

Hierarchical assembly of arc-like fractal nanostructures not only has its unique self-similarity feature for stability enhancement but also possesses the structural advantages of highly exposed surface-active sites for activity enhancement, remaining a great challenge for high-performance metallic nanocatalyst design. Herein, we report a facile strategy to synthesize a novel arc-like hierarchical fractal structure of PtPd bimetallic nanoparticles (h-PtPd) by using pyridinium-type ionic liquids as the structure-directing agent. Growth mechanisms of the arc-like nanostructured PtPd nanoparticles have been fully studied, and precise control of the particle sizes and pore sizes has been achieved. Due to the structural features, such as size control by self-similarity growth of subunits, structural stability by nanofusion of subunits, and increased numbers of exposed active atoms by the curved homoepitaxial growth, h-PtPd displays outstanding electrocatalytic activity toward oxygen reduction reaction and excellent stability during hydrothermal treatment and catalytic process.

The effects of medicinal and food homologous substances on blood lipid and blood glucose levels and liver function in patients with nonalcoholic fatty liver disease: a systematic review of randomized controlled trials.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a prevalent chronic liver disorder worldwide. According to several previous studies, the treatment of patients with NAFLD using medicinal and food-homologous substances has consistent effects on the levels of blood lipids and blood glucose and liver function. OBJECTIVE: This systematic review was conducted to investigate the impact of medicinal and food homologous substances on blood lipid and glucose levels as well as liver function in patients with NAFLD. METHODS: A thorough search was conducted in eight databases, including China Science and Technology Journal Database (VIP), Chinese National Knowledge Infrastructure(CNKI), China Biomedical Literature Database (SinoMed), Wanfang Database, PubMed, Cochrane Library, Web of Science and Embase, for articles published from database inception until June 24, 2023. The methodological quality of the included studies was evaluated utilizing Cochrane Randomized Trial Risk Bias Tool, Edition 2 and GRADE methodology for assessment. RESULTS: A total of 13 randomized controlled trials, involving 829 patients with NAFLD, were included in the analysis, these studies included a total of 9 medicinal and food homologous substances. In the 13 studies, hawthorn (2), sea buckthorn (1), ginger (2), turmeric (4) (1 with chicory seeds), cinnamon (1), cardamom (1), purslane (1) and saffron (1) were included. The results of the included studies showed that medicinal and food homologous substances could improve high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglycerides (TGs), fasting blood glucose (FBG) and liver enzyme levels in patients with NAFLD to a certain extent, but the effect of turmeric on TC, liver enzyme levels is controversial. CONCLUSION: In patients with NAFLD, dietary intervention using medicinal and food homologous substances can ameliorate blood lipid and blood glucose levels and liver enzymes to some extent. In clinical work, medicinal and food homologous substances can be used to provide patients with NAFLD with a safe and effective dietary plan to help prevent and treat disease onset and progression.

The effects of replacing fish meal or soy protein concentrate with wheat gluten on growth, whole-body composition, and the retention and apparent digestibility coefficient of amino acids in Japanese seabass (Lateolabrax japonicus).

The aim of this study was to evaluate the effects of replacing fish meal (FM) or soy protein concentrate (SPC) with wheat gluten on growth performance, feed utilization, and nutrient digestibility and retention in Japanese seabass (Lateolabrax japonicus). Seven isonitrogenous (441-456 g kg-1 crude protein) and isocaloric (21.5-22.0 MJ kg-1 gross energy) diets were produced to replace 0%, 33.3%, 66.7% and 100% of FM or SPC with a mixture of wheat gluten, wheat, and taurine (GWT, 77.5% wheat gluten, 20.5% wheat and 2.0% taurine). The gradual replacement of protein in FM with GWT had no significant effects on feed intake, whole-body composition, and the hepatosomatic and viscerosomatic indices, but resulted in a linear decrease in the weight gain rate, feed efficiency, and retention of nitrogen, energy, and essential amino acids (Arg, His, Ile, Leu, Lys, Met, Phe, Thr, and Val). The apparent digestibility of most essential amino acids (Cys, His, Leu, Lys, and Phe) and total amino acids increased linearly. Replacement protein in SPC with GWT had no significant effects on feed intake, growth, the feed conversion ratio, whole-body composition, and the hepatosomatic index, but resulted in a linear decrease in nitrogen, energy, and Met retention; the digestibility of Cys and Met increased linearly. Overall, wheat gluten is a more effective alternative for replacing protein in SPC than FM.

Evaluate of Wheat Gluten as a Protein Alternative for Fish Meal and Soy Protein Concentrate in Red Spotted Grouper Epinephelus akaara.

The aim of this study was to evaluate the effects of wheat gluten as a substitute for fish meal (FM) and soy protein concentrate (SPC) in the low-fishmeal-based extruded diet in red spotted grouper Epinephelus akaara. Eight isonitrogenous (441-456 g kg-1) and isocaloric (21.5-22.0 MJ kg-1) diets were produced, including the control diet (R0), three diets with 33.3, 66.7, and 100% FM being replaced by a mixture of wheat gluten, wheat, and taurine (GWT) (RF1, RF2, RF3), three diets with 33.3, 66.7, and 100% SPC replaced by GWT (RS2, RS2, RS3) and one diet with 50% FM and 50% SPC replaced by GWT (RFS). Results showed that feed intake (FI), weight gain (WG), protein retention efficiency, and liver superoxide dismutase activity increased linearly, while feed conversion ratio (FCR) decreased linearly with the decrease of dietary FM. Additionally, FI, WG, and FCR significantly increased with decreasing dietary SPC. Overall, 100% FM or 61.2% SPC can be safely replaced by wheat gluten in the red-spotted grouper diet containing 20.0% FM and 21.4% SPC.

Atomically Dispersed Ni-N4 Sites Assist Pt3 Ni Nanocages with Pt Skin to Synergistically Enhance Oxygen Reduction Activity and Stability.

Currently, the rarity and high cost of platinum (Pt)-based electrocatalysts seriously limit their commercial application in fuel cells cathode. Decorating Pt with atomically dispersed metal-nitrogen sites possibly offers an effective pathway to synergy tailor their catalytic activity and stability. Here active and stable oxygen reduction reaction (ORR) electrocatalysts (Pt3 Ni@Ni-N4 -C) by in situ loading Pt3 Ni nanocages with Pt skin on single-atom nickel-nitrogen (Ni-N4 ) embedded carbon supports are designed and constructed. The Pt3 Ni@Ni-N4 -C exhibits excellent mass activity (MA) of 1.92 A mgPt -1 and specific activity of 2.65 mA cmPt -2 , together with superior durability of 10 mV decay in half-wave potential and only 2.1% loss in MA after 30 000 cycles. Theoretical calculations demonstrate that Ni-N4 sites significant redistribute of electrons and make them transfer from both the adjacent carbon and Pt atoms to the Ni-N4 . The resultant electron accumulation region successfully anchored Pt3 Ni, that not only improves structural stability of the Pt3 Ni, but importantly makes the surface Pt more positive to weaken the adsorption of *OH to enhance ORR activity. This strategy lays the groundwork for the development of super effective and durable Pt-based ORR catalysts.

Synthesis of Pore-Wall-Modified Stable COF/TiO2 Heterostructures via Site-Specific Nucleation for an Enhanced Photoreduction of Carbon Dioxide.

Constructing stable heterostructures with appropriate active site architectures in covalent organic frameworks (COFs) can improve the active site accessibility and facilitate charge transfer, thereby increasing the catalytic efficiency. Herein, a pore-wall modification strategy is proposed to achieve regularly arranged TiO2 nanodots (≈1.82 nm) in the pores of COFs via site-specific nucleation. The site-specific nucleation strategy stabilizes the TiO2 nanodots as well as enables the controlled growth of TiO2 throughout the COFs' matrix. In a typical process, the pore wall is modified and site-specific nucleation is induced between the metal precursors and the organic walls of the COFs through a careful ligand selection, and the strongly bonded metal precursors drive the confined growth of ultrasmall TiO2 nanodots during the subsequent hydrolysis. This will result in remarkably improved surface reactions, owing to the superior catalytic activity of TiO2 nanodots functionalized to COFs through strong NTiO bonds. Furthermore, density functional theory studies reveal that pore-wall modification is beneficial for inducing strong interactions between the COF and TiO2 and results in a large energy transfer via the NTiO bonds. This work highlights the feasibility of developing stable COF and metal oxide based heterostructures via organic wall modifications to produce carbon fuels by artificial photosynthesis.

Tuning the water-splitting mechanism on titanium dioxide surfaces through hydroxylation.

Experimental research demonstrates that surface hydroxyl groups can boost TiO2's ability to split water but the water splitting mechanism and roles of hydroxyl groups are still not clear. The hydroxyl groups formed by H2O or H2 cracking on pure TiO2 surfaces are represented by types I (OH1) and II (OH2), respectively. Six types of hydroxylated TiO2 surfaces of anatase (101), rutile (110), and brookite (210) with OH1 and OH2 hydroxyl groups were constructed. The mechanism of the water oxidation process on the hydroxylated TiO2 surfaces was systematically investigated through density functional theory calculations. The variation and significant roles of hydroxyl groups in the mechanism of the oxygen evolution reaction (OER) and product selectivity were discussed. All hydroxylated TiO2 surfaces eventually tend to produce oxygen through a four-electron/proton process, which is fundamentally different from the OER process on pure Ti2O surfaces from a thermodynamic standpoint. The lowest surface overpotential of R-110-OH1 is 0.53 V, the highest surface overpotential of B-210-OH2 is 1.49 V, and the surface overpotentials of other hydroxylated TiO2 are between 0.5 and 1.5 V. Rutile (110) and brookite (210) have hydroxyl groups of the OH1-type that are more conducive to the OER process. This study investigates the mechanism of water splitting on the surface of hydroxylated TiO2, allowing for a deeper understanding of the function of surface hydroxyl groups in the OER process as well as providing instructions for future research into the development of effective water-splitting catalysts based on hydroxylated TiO2 surfaces.

Evaluation of intervention effects of dietary coenzyme Q10 supplementation on oxidized fish oil-induced stress response in largemouth bass Micropterus salmoides.

The aim of this experiment was to investigate whether dietary coenzyme Q10 could alleviate stress response of Micropterus salmoides caused by oxidized fish oil. Four isonitrogenous and isoenergetic diets were formulated to contain 100% fresh fish oil (FFO), 50% fresh fish oil + 50% oxidized fish oil (BFO), 100% oxidized fish oil (OFO) and 100% oxidized fish oil + 0.1% coenzyme Q10 (QFO) and were fed to Micropterus salmoides (95 ± 0.60 g) for 70 days. Higher weight gain rate was recorded in fish fed diet supplemented with coenzyme Q10 (CoQ10). FFO and BFO significantly increased contents of fat and energy in whole-body, while protein and energy retention significantly decreased in fish fed OFO. Apparent digestibility of energy and fat showed a significant decrease trend with increased the proportion of dietary oxidized fish oil. Fish fed OFO significantly increased activities of superoxide dismutase and catalase, while CoQ10 supplementation significantly reduced activities of alanine aminotransferase and aspartate aminotransferase in plasma. Contents of n-3 polyunsaturated fatty acids and highly unsaturated fatty acids, especially EPA and DHA in liver and muscle significantly decreased in fish fed OFO. Transcriptome analysis indicated that a total of 1238, 1189 and 1773 differentially expressed genes (DEGs, |log2(fold change) | >= 1 and q-value<=0.001) were found in the three comparison groups (FFO vs. OFO, FFO vs. QFO, OFO vs. QFO), respectively. After KEGG enrichment, the main changed pathways in the two comparison groups (FFO vs. OFO, OFO vs. QFO) related to the immune system. Dietary OFO up-regulated the expression of immune-related genes and inflammatory factors, while dietary CoQ10 supplementation reduced these effects.

Hydrogen-Bond Regulation of the Microenvironment of Ni(II)-Porphyrin Bifunctional Electrocatalysts for Efficient Overall Water Splitting.

Accurately regulating the microenvironment around active sites is an important approach for boosting the overall water splitting performance of bifunctional electrocatalysts, which can drive both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) in the same electrolyte. Herein, pseudo-pyridine-substituted Ni(II)-porphyrins (o-NiTPyP, m-NiTPyP, and p-NiTPyP) with pseudo-pyridine N-atoms located at the ortho-, meta-, or para-position are prepared and used as model catalysts for alkaline water splitting. Experimental and theoretical results reveal that the pseudo-pyridine N-atom positions can regulate the microenvironment around the active sites and the adsorption free energy of H-donating substances by affecting the H-bonding interaction and the NNiN bond angles of active sites, and thus those pseudo-pyridine-substituted Ni(II)-porphyrins deliver better electrocatalytic activity than the Ni(II)-tetraphenylporphyrin (NiTPP) without pseudo-pyridine N-atoms. Among them, m-NiTPyP on carbon nanotubes delivers the lowest overpotentials of 267 and 138 mV at 10 mA cm-2 for the OER and HER, respectively. Specifically, m-NiTPyP as bifunctional electrocatalyst in an alkaline electrolyzer requires only 1.62 V to drive efficient overall water splitting at 10 mA cm-2 while remaining durable. This work proposes a new H-bond-regulating approach of the microenvironment of electrocatalysts for effectively boosting the overall water splitting activity and deeply understanding its related mechanism.

Construction of Photo-Responsive Pd2 L4 -Type Nanocages based on Feringa's Second-Generation Motor and Its Guest Binding Ability for C60.

We present the construction of a M2 L4 -type metal-organic nanocage featuring four endohedral Feringa's motor motifs and its adaptive encapsulation towards a C60 guest molecule. The structure of the cage, though complicated on the 1 H NMR spectrum due to the adoption of mixed ligands, was unambiguously characterized with a combination of ESI-MS, 2D DOSY, 13 C NMR and particularly the SAXS technique. The molecular motor within the cage demonstrated similar photophysical properties to the uncoordinated one, indicating the motor's function was not compromised when it was anchored in such a confined nanospace. Furthermore, the nanocage showed good guest encapsulation ability towards C60 , and a guest induced-fit behavior of the cage was revealed based on the extensive SAXS analysis and molecular dynamics simulation. The adaptive motorized nanocage reported here represents one of the very few examples of integrating individual motors into a discrete nanoconfined system and offers prospects to achieve its non-equilibrium functions.

Electronic structures of hydroxylated low index surfaces of rutile and anatase-type titanium dioxide.

Different surface planes of various types of titanium dioxide (TiO2) crystals have diverse catalysis effects on the splitting of H2O and H2 and the electronic structures of the formed hydroxylated TiO2 vary significantly. A series of sixteen types of hydroxylated TiO2 surfaces containing two types of hydroxyls (OH1 and OH2) on four kinds of low index surfaces [(001), (100), (101), and (110)] of two types of crystals [anatase (A) and rutile (R)] are studied using first-principles density functional theory calculations. The catalyzed splitting of H2O and H2 on the eight low index surfaces is compared using Gibbs free energy. The geometries and electronic structures including the total and partial density of states and the charge density distribution of the sixteen hydroxylated surfaces are systematically described. The electronic structures of R-101, R-001, A-110, A-100, and A-001 surfaces are more significantly influenced by hydroxylation than other surfaces and the effects of OH2 are larger than those of OH1. In particular, the band gap values decrease and a new electronic energy state appears in R-001-OH2 and A-100-OH2. A new electronic state appears in the middle of the bands of R-101 and A-110 surfaces upon hydroxylation. The electron spin balance at the edge of the conduction band minimum of A-001-OH2 is disturbed. This research can provide theoretical guidance for experimental researchers to design surface hydroxylated TiO2 materials with tunable electronic structures and high catalytic performance.

Near-infrared irradiation controlled thermo-switchable polymeric photosensitizer against ß-amyloid fibrillation.

Photothermal therapy (PTT) is an emerging paradigm for the degradation of amyloid-ß (Aß) aggregations and has become an effective way of treating Alzheimer's disease (AD). A promising PTT therapeutic option requires control of at least two key functional aspects: controllable photoactivity and specific activation. In this work, a near-infrared (NIR)-activated thermo-switchable biopolymeric PTT agent was designed and synthesized by conjugating a molecular rotor-based boron dipyrromethene photosensitizer (BDP) to a temperature-responsive polymer backbone of biopolymeric hydroxypropyl cellulose (HPC). The as-synthesized BDP-HPC exhibited an ultra-high PCE of 78.1% along with prominent cycling stability of phase-transition behavior under NIR irradiation in the light of the lower critical solution temperature (LCST at 42.5 °C). Importantly, the NIR irradiation can manipulate the reversible phase transition behavior of the resultant BDP-HPC that reveals high effectiveness in inhibiting Aß aggregation together with the obvious ability to dissociate Aß aggregations. Our work reveals an accurate modulation strategy for versatile and high-performance AD treatment.

Novel Prenylated Indole Alkaloids with Neuroprotection on SH-SY5Y Cells against Oxidative Stress Targeting Keap1-Nrf2.

Oxidative stress has been implicated in the etiology of Parkinson's disease (PD). Molecules non-covalently binding to the Keap1-Nrf2 complex could be a promising therapeutic approach for PD. Herein, two novel prenylated indole alkaloids asperpenazine (1), and asperpendoline (2) with a scarce skeleton of pyrimido[1,6-a]indole were discovered from the co-cultivated fungi of Aspergillus ochraceus MCCC 3A00521 and Penicillium sp. HUBU 0120. Compound 2 exhibited potential neuroprotective activity on SH-SY5Y cells against oxidative stress. Molecular mechanism research demonstrated that 2 inhibited Keap1 expression, resulting in the translocation of Nrf2 from the cytoplasm to the nucleus, activating the downstream genes expression of HO-1 and NQO1, leading to the reduction in reactive oxygen species (ROS) and the augment of glutathione. Molecular docking and dynamic simulation analyses manifested that 2 interacted with Keap1 (PDB ID: 1X2R) via forming typical hydrogen and hydrophobic bonds with residues and presented less fluctuation of RMSD and RMSF during a natural physiological condition.

Researching pointing error effect on laser linewidth tolerance in space coherent optical communication systems.

In order to evaluate the pointing error effect on laser linewidth tolerance in a space coherent optical communication system, we derive a closed-form bit error rate (BER) model for binary phase-shift-keying (BPSK) modulation and heterodyne detection, under atmospheric turbulence, pointing error and laser phase noise. Based on the BER model, the linewidth tolerance is given, and numerical simulation is conducted. We find that laser linewidth tolerance decreases greatly with the increase of pointing error. Considering that pointing error consists of jitter and boresight, the effect of jitter and boresight are discussed separately and jointly in detail. Our results show that laser linewidth tolerance is more sensitive to the jitter variation than the boresight variation. In addition, with the increasing of the pointing error, the linewidth tolerance decreases faster under the large pointing error as compared to the case under the small pointing error. This paper is a good reference for designing space coherent optical communication systems.

Aspartic Acid-Assisted Size-Controllable Synthesis of Nanoscale Spherical Covalent Organic Frameworks with Chiral Interfaces for Inhibiting Amyloid-ß Fibrillation.

Covalent organic framework nanospheres (COF NSs) have garnered special attention due to their uniform sphere morphology, adjustable particle size, and mesoporous microenvironment. However, methods to control an optimal particle size scale while achieving solution dispersibility and specific surface properties remain underdeveloped, which precludes many of the biomedical applications. Here, we propose and develop a general strategy to access simultaneous size control and surface functionalization of uniform spherical COF NSs in a single step using aspartic acid (d-/l-Asp) that plays center roles in an acid catalyst, hydrophilicity, size-controllable synthesis, and chiral enantiomer. In this study, for the first time, we have employed a surface chemistry engineering study to create a variety of nanoscale spherical COFs and subsequently measure parameters to evaluate the effectiveness of Asp in the regulation of the particle size. Moreover, the potential utilization of the d/l-enantiomeric Asp-COF NSs in preventing ß-amyloid (Aß) aggregation is investigated by analyzing their interactions with Aß amyloids using a multitechnique experimental approach. To our knowledge, our strategy is the first synthesis of hydrophilic COF NSs with an optimal length scale and a chiral-selective targeting surface, which are crucial for the inhibition of Aß fibrillation for Alzheimer's disease prevention.

Solvent-Mediated Synthesis of Hierarchical MOFs and Derived Urchin-Like Pd@SC/HfO2 with High Catalytic Activity and Stability.

Carbon materials with hierarchical morphologies, pores, and compositions have attracted extraordinary attention due to their unique structural advantages and widespread applications. However, their controllable synthesis remains a grand challenge. Herein, a solvent-mediated strategy was demonstrated for the preparation of an urchin-like superstructure via modulating the hydrothermal condition (acetic acid/water ratio) of metal-organic frameworks (MOFs). The direct pyrolysis of a hierarchical NUS-6 precursor produced a well-defined carbon-based composite consisting of sulfur-doped carbon (SC) and HfO2 with an urchin-like morphology and micro-/mesoporosity, while the doped S sites and oxygen vacancies of HfO2 can help to anchor and activate Pd nanoparticles (NPs) through the strong host-guest interaction, which was further confirmed by the calculated results of the binding energy and differential charge density through density functional theory (DFT). The synthesized Pd@SC/HfO2 composite exhibited extremely high catalytic activity and stability toward the water-phase hydrodeoxygenation of vanillin (conversion >99%, selectivity >99%), as well as good universality for the hydrogenation of a series of unsaturated hydrocarbons in an aqueous system. Remarkably, the catalytic activity and structural stability of Pd@SC/HfO2 were largely maintained even after successive 10 cycles.