Chem. J. Chinese Universities-Forthcoming Articles

Synthesis, Crystal Structure, and Catecholase Activity of N,N,N Tridentate Schiff base Ligand Based Copper(II) Complexes

BAI Yize, LIU Ruiduan, LU Qiuran, ZHAO Haiyan — 2024-04-19 00:00:00.0

Four complexes, [Cu(L1)Cl2] (1), [Cu(SCN) 2] (2), [Cu(L1)bpy](ClO4)2·CH3OH (3), and [Cu(L2)bpy](ClO4)2 (4) were synthesized by reacting the NNN tridentate Schiff base ligands, 2-((1H-benzimidazol-2-yl-ethylimino)-methyl) pyridine (L1) or 2-((1H-benzimidazol-2-yl-propylimino)-methyl) pyridine (L2) with Cu(II) salts in methanol (where bpy = 2, 2’-bipyridine). The structures of the complexes were characterized by elemental analysis, infrared spectroscopy, powder X-ray diffraction, single-crystal X-ray diffraction and thermal gravimetric analysis. In the solid state, complexes 1-4 are mononuclear Cu(II) complexes and the Cu(II) ions exhibit distorted square pyramidal coordination geometry, with τ values ranging from 0.088 to 0.34. Catecholase activity of the complexes has been studied using 3, 5-di-tert butyl catechol (3, 5-DTBC) as model substrate, and kinetic parameters (Vmax, Kcat, KM) were calculated using the Michaelis-Menten model and Lineweaver-Burk plot. The results demonstrate that all complexes exhibit catecholase activity, with the catechol oxidation rates following the order of 2>3≈4>1. The oxidation rates depend on the distortion of the Cu(II) coordination environment and the bond lengths of the leaving group of Cu(II) ions.

Theoretical Research of Two-dimensional Semiconductor R57-BN as Anode Material of Sodium-ion Battery

WANG Wenchun, MA Tianci, LIU Chunsheng — 2024-04-19 00:00:00.0

As promising alternatives to lithium-ion batteries (LIBs), sodium-ion batteries (SIBs) have garnered significant interest owing to the abundant resources, low cost, and similar storage mechanism with LIBs. However, the lack of suitable anode materials is a major bottleneck of SIBs. Two-dimensional (2D) materials are promising anode materials for batteries due to their large surface area and short diffusion paths. In this paper, a pentagonal and heptagonal 2D semiconductor structure R57-BN composed of B and N atom is predicted, and the electrochemical properties of R57-BN as anode material of SIBs is systematically study based on first-principles calculations. 2D R57-BN shows great stability in dynamic and thermodynamic aspects. The computation results reveal that Na atom can be adsorbed on R57-BN without clustering, and the adsorbed energy of Na-ion on the R57-BN is 1.55 eV. Even at low intercalated Na concentration, the Na adsorbed R57-BN system demonstrates metallic characteristics, showing good electronic conductivity. The diffusion barrier of Na diffusion on the surface of R57-BN is as low as 0.55 eV. Meanwhile, R57-BN has high specific capacity (662.40 mA h g-1) and suitable average OCV (0.50 V). Based on the above results, R57-BN can serve as a potential anode material for SIBs. The present research can provide a good theoretical basis and thus conduce to guiding the developing of good Na storage materials, and also supply strong background for experimental researches.

An Electrically Responsive Multiple Chiroptical Switching System Based on a Rhodol Derivative

WANG Tongtong, WANG Tiefeng, XU Fei, YU Yang — 2024-04-17 00:00:00.0

In this study，a chiral aniline structure was introduced into the Rhodol (3’-amino-6’-hydroxyspiro[2-benzofuran-3,9’-xanthene]-1-one) derivative main molecule，which exhibits pH (acid and base)-responsive color changes. Then，based on the proton-coupled electron transfer mechanism，a novel electrically responsive multiple chiroptical switching system was constructed by integrating the functional Rhodol derivative with electro-acid/base molecules. Controlled by suitable voltages，this system could switch among three circular dichroism absorption states reversibly: in the visible light range，no circular dichroism signal at the initial state，positive circular dichroism signal under a significant positive voltage，and negative circular dichroism signal under a considerable negative voltage. More importantly，all the switching processes were totally reversible. This research opens a new route to achieve the development of electrically responsive multiple chiroptical switching systems，and offers an important insight on the design and application of innovative materials for multiple chiroptical switches.

Detection of Perfluorooctane Sulfonate in Aqueous Environment Based on Molecular Imprinting Coupled Bipolar Electrochemiluminescence Sensor

HUANG Shengxiu, LIU Liyang, YANG Weiqiang, WANG Qingxiang, NI Jiancong — 2024-04-17 00:00:00.0

MIP/BPECL sensor was constructed for the detection of perfluorooctane sulfonic acid (PFOS) in sewage by combining the specific recognition ability of molecular imprinting (MIP) and the high sensitivity and anti-interference characteristics of bipolar electrochemical luminescence sensing (BPECL). Using PFOS as the template molecule and O-phenylenediamine (o-PD) as the functional monomer, the molecular-imprinted polymer was specifically identified by negative extreme electropolymerization of bipolar electrodes. The electrodes were characterized by scanning electron microscopy and cyclic voltammetry. The MIP/BPECL sensing system was constructed with Ruthenium bipyridine/tri-n-propylamine (Ru(bpy)32+/TPrA) as output signal at the positive extremity of the bipolar electrode. Under optimized conditions, the electrochemical sensor displayed a wide linear range from 1 to 1000 nM with the low limit of detection of 0.43 nM (S/N=3). The sensor is applied to the actual sample of environmental water labeling recovery test, and the result is good. The constructed MIP/BPECL has the advantages of high sensitivity, good specificity and strong anti-interference ability. By changing the template molecule of molecular imprinting, it is expected to realize the application of this sensor in the detection of other environmental pollutants.

Review on allergen detection in aquatic products

Zuo Chunqian, Xu Ruirui, Bi Hongyan — 2024-04-17 00:00:00.0

Food allergy is an abnormal reaction of the body's immune system to certain foods. It is a health problem that has gained widespread attention around the world. Food allergies commonly occur as a result of the immune system's response to specific foods, often mediated by immunoglobulin E or immune cells. Allergens play a key role in triggering these reactions, underscoring the importance of detecting and identifying allergens to maintain food safety. As an important source of protein, aquatic products are an indispensable part of people's daily diet, the detection of allergens in aquatic products is highly necessary. This review briefly describes the research progress of allergen detection in aquatic products such as fish and shellfish in recent years, and summarizes common allergens, detection methods and technologies, as well as challenges in current research and future development trends. At present, the detection methods for common food allergens currently face challenges, including limitations associated with low detection efficiency, reduced accuracy and high overall costs. These constraints underscore the need for ongoing research and innovation in this area to address these shortcomings. Combining different technical methods to establish efficient, accurate and low-cost allergen detection methods is still an important trend in the development of this research field.

Phase transfer catalyzed toluene of oxidation to benzaldehyde using tetrameric quaternary ammonium polyoxometalates

QIAN Shu, YU Fengli, GU Xue, YUAN Bing, XIE Congxia, YU Shitao — 2024-04-12 00:00:00.0

The oxidation of toluene to benzaldehyde in industrial applications typically involves toxic reagents or the generation of various difficult-to-separate byproducts. In this study, starting materials such as ethylenediamine, epichlorohydrin, and N,N-dimethyldodecylamine were used to synthesize tetrameric quaternary ammonium chloride. Subsequently, an anion exchange reaction with Keggin-type tungstovanadophosphoric heteropolyacid was conducted to prepare tetrameric quaternary ammonium polyoxometalates. These polyoxometalate catalysts were then evaluated via the oxidation of toluene to benzaldehyde using H2O2 (30 wt.%) in acetonitrile. The introduction of four nucleated cations not only modulated the redox properties of the heteropolyanions but also provided the catalyst with densely packed cooperative catalytic active sites. Additionally, the resulting catalyst exhibited excellent amphiphilic phase-transfer catalytic capabilities, significantly enhancing the reaction rate and enabling easy catalyst recovery for repeated use. After seven repeated uses, the catalyst's performance showed minimal decline, maintaining acceptable toluene conversion (40%) and benzaldehyde selectivity (75%). Therefore, this study has developed an environmentally friendly process for the catalytic oxidation of hydrocarbons relevant to industry, laying a theoretical foundation for practical industrial applications.

Untargeted Lipidomics Reveals Lipid Metabolism Dysfunction During Macrophage Foaming

WANG Zengyu, LIU Baohong, QIAO Liang, LIN Ling — 2024-04-12 00:00:00.0

Atherosclerosis is a multifactorial chronic complex disease characterized by the accumulation of lipids, inflammatory responses, and ultimately fibrous plaque formation within arterial walls. Plaque formation begins with the abnormal accumulation of lipids engulfed by macrophages within arterial walls, forming so-called foam cells. Despite the pivotal role of foam cell formation in the pathophysiological remodeling process of blood vessels, in-depth research into lipid metabolism disturbances during macrophage foam cell formation is still relatively lacking. In this study, we constructed and optimized a lipidomics analysis workflow, applying it to analyze metabolic reprogramming during macrophage foam cell formation. A total of 645 lipid molecules belonging to 16 lipid subclasses were identified. Principal component analysis, time-series pattern analysis, and volcano plot analysis revealed significant differences in lipid levels at different stages of foam cell formation. As incubation time with oxidized low-density lipoprotein increased, the degree of lipid metabolism dysfunction in foam cells increased. Triglycerides, hemolytic phospholipids, and ether phospholipids were upregulated, while phosphatidylserine was downregulated. The significant accumulation of triglycerides enhanced the inflammatory response of macrophages, promoting foam cell formation by further engulfing oxidized low-density lipoprotein. Meanwhile, the synthesis of phosphatidylserine and hemolytic phosphatidylcholine increased significantly in the late stages of foam cell formation, indicating a positive correlation between foam cell formation and cell apoptosis. These lipid molecules may serve as signaling molecules to attract macrophages for the clearance of apoptotic cells. Our study not only reveals the significant upregulation of inflammatory responses during foam cell formation but also elucidates the close connection between lipid metabolism disturbances and cell apoptosis signaling.

Preparation of Electro-nanofiltration Membranes with High Li+/Mg2+ Separation Performance via Sequential Interfacial Polymerization

2024-04-12 00:00:00.0

Highly selective electro-nanofiltration membranes (ENFMs) were prepared by regulating the aqueous-phase monomers of interfacial polymerization (IP) and constructing the positively charged surface by sequential interfacial polymerization (SIP) for the separation of lithium and magnesium by selective electrodialysis processes. The IP reaction was carried out using different aqueous-phase monomers with trimesoyl chloride to achieve the regulation of the pore size and charging property of the separation membranes. The optimum Li+/Mg2+ separation performance (4.75) of the membrane was achieved when piperazine was used as the aqueous-phase monomer. Subsequently, the SIP reaction was utilized to introduce positively charged aqueous-phase monomer polyethyleneimine (PEI, M.W. =70 kDa) of different concentrations on the optimal IP membrane surface, which converted the charge of the membrane surface from negative to positive. With the increase of PEI concentration, the positive charge density on the membrane surface increased significantly; the optimal SIP membrane achieved outstanding selectivity for Li+/Mg2+ (15.9) and high Li+ flux (3.26 × 10-8 mol·cm-2·s-1), which breaks the traditional “Trade-off” effect and lays the foundation for the subsequent research and application of Li+/Mg2+ separation salt-lake brines.

Renal Clearance of Sodium Alginate Stabilized Au Nanoclusters

WANG Tianyuan, ZHANG Huazhen, ZHAO Pin, WANG Kai, LIN Min — 2024-04-10 00:00:00.0

In this work, biocompatible and biodegradable sodium alginate (SA) was used to stabilize Au nanoclusters (NCs). Combined with the chemical inertness of Au, SA-AuNCs of 4.2±0.9 nm in diameter exhibited extremely low cytotoxicity. After administrated into mice, SA could delay the renal clearance of SA-AuNCs and prolong the half-life to 8.2±0.2 h in blood circulation. Thus the tumor uptake rate was increased to 10.4% ID/g. When tumor area contained high concentration of calcium ions, the tumor uptake rate could be further improved to 14.5% ID/g due to cross-link between Ca2+ and SA. The SA-AuNCs were mainly excreted through renal clearance, which only involved minor, but recoverable interference to the renal function. This indicates good biosafety of SA-AuNCs. This work can solves the contradiction between the renal clearance and tumor uptake of nanoclusters by using functional of ligands, which provides theoretical guidance for other high-performance diagnostic and therapeutic nanomaterials.

Broadband Dielectric Spectroscopy Study of Dynamics of Telechelic Polypropylene Glycol Melts

BAI Rong, LI Shangwei, CHEN Quan, SUN Zhaoyan, XU Wensheng — 2024-04-10 00:00:00.0

Excellent polymer electrolytes require a combination of high ionic conductivity and mechanical strengths. An in-depth understanding of the relationship between polymers’ microscopic structure and dynamics and macroscopic conductive and mechanical properties is essential for the molecular design of high-performance polymer electrolytes. In the present paper, we selected low Tg and non-crystalline telechelic polypropylene glycol melts as a model system to investigate the molecular dynamics of associating polymers. Allyl-terminated polypropylene glycols having molecular weights of 1000, 2000 and 4000 g/mol were synthesized by chemically modifying the end groups, and the influence of chain-end interaction strength and molecular weight on their multi-scale dynamics was investigated using broadband dielectric spectroscopy. The polypropylene glycols with two different end groups exhibit both the α-relaxation associated with the segmental motion and the normal mode relaxation associated with the global motion of the chain. End group interactions influence both two relaxations; stronger interactions lead to larger relaxation times at the same temperature. This effect becomes more pronounced for the lower-molecular-weight samples, because the motion has been suppressed for the denser end groups therein. The generalized entropy theory was utilized to study the glass formation of telechelic polymer melts having variable sticky interaction strength and molecular mass, and theoretical predictions were shown to be in qualitative agreement with experimental results. These dynamic details can be used in guiding the molecular design of polymer electrolytes.

Preparation of Superhydrophobic Porous Organic Polymers and Application of its Oil-Water Separation Performance

2024-04-08 00:00:00.0

In the course of this investigation, a superhydrophobic porous organic polymer denominated as LNU-40 was synthesized via a Suzuki coupling reaction. The aforementioned reaction involved the utilization of 4-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-N,N-bis[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]aniline, 3,6-Dibromocarbazole, Tetrakis(triphenylphosphine)palladium, and N,N-Dimethyl-2-(piperazin-1-yl)benzamide oxalate. LNU-40 possesses a specific surface area of 32 m2g-1 and manifests thermal stability. Dissolution or decomposition does not occur when it is dispersed in commonly encountered organic solvents. LNU-40 is characterized by a low surface energy and a water contact angle of 152.4°, demonstrating excellent resistance to acidic and alkaline environments. This property enables the fabrication of a superhydrophobic surface with outstanding self-cleaning capabilities. The superhydrophobic flexible fabric, fabricated using LNU-40, achieves a separation efficiency of over 90% for organic solvents and exhibits an oil adsorption capacity ranging from 3 to 8 times its own weight. The superior adsorption and separation performance make it suitable for the treatment of oily wastewater containing organic solvents in industries such as petrochemicals, food, and pharmaceuticals.

Preparation of porous carbon nanofiber loaded copper-platinum alloy catalysts and their electrocatalytic hydrogen evolution performance

CHEN Xin, LIU Jingyuan, YU Jing — 2024-04-07 00:00:00.0

In this investigation, a series of PtCu nano-alloy catalysts with varying alloy ratios were prepared on porous carbon nanofibers (PCNFs) using electrostatic spinning and staged heat treatment methods. The effect of the geometrical morphology of the alloy particles and the Cu-Pt-Cu structure on the hydrogen evolution efficiency were discovered. The study determined that the most effective hydrogen evolution performance was achieved using a PtCu additive mass ratio of 1:2 under acidic conditions, resulting in an overpotential of 37 mV at 10 mA cm-2 and exhibiting robust long-term stability. This research presents an innovative approach for producing binary alloy nanocatalysts of PCNFs impregnated with transition metals and Pt.

A Mechanism upon Conversion of Syngas Catalyzed by Single Atom Mo Supported on Graphene: Role of Carbon Component and Impact from Mo-C Interactions

KONG Xue, ZHANG Haiping, XIA Wensheng, ZHANG Qinghong, WAN Huilin — 2024-04-07 00:00:00.0

The catalytic behaviors of metal for syngas conversion is related to the carbonization of the metal, however, the formed metallic carbides are of complicated composition and structures, making the identification of the active phase of the catalysts be challengeable, so it is significant to investigate the role of the carbon component of the catalysts. In this work, we studied computationally mechanisms of syngas conversion to alcohols on single atom Mo supported on pristine graphene (Mo/pri-graphene) and single-carbon vacant graphene (Mo/sv-graphene) by means of density functional theory (DFT) method to explore the regulated effect of carbon component on C-O activation. The results show that it is significantly different for mechanisms of syngas conversion on Mo/pri-graphene with weak Mo-C interactions and Mo/sv-graphene with strong Mo-C interactions. On Mo/pri-graphene the preferred pathway is, CO → HCO → CH2O → CH3O → CH3/CH4, and species CH3O is of some stability due to high activation free energy of its further transformation into CH3/CH4, while on Mo/sv-graphene the preferred pathway is, CO → HCO → CH2O → CH2OH → CH3OH/CH3(CH4), and the coexistence of species CH3OH and CH3(CH4) provides a possibility for the following carbon chain propagation. The activation free energy of the elementary steps of CO hydrogenation on Mo/sv-graphene is generally lower than on Mo/pri-graphene. The reasons are the lower interactions between Mo/sv-graphene and the substrate, and the participation of the carbon component of Mo/sv-graphene during the activation/transformation of the substrate. Thus, the carbon component of catalysts can regulate (and/or take participate in) the interaction of the catalysts with the substrates, and then make an improvement on the activity and selectivity.

Assembly of Functionalized MIL-101-loaded Quartz Crystal Microbalance Gas Sensors for Formic Acid Detection

2024-04-07 00:00:00.0

Volatile organic compounds (VOCs) are considered as one of the major components in atmospheric pollutants, and pose serious hazards to both human health and the environment. It is urgent to develop new high-efficient detection techniques for VOCs. In this work, ethylenediamine (ED) and ethanolamine (EA) were grafted into MIL-101(Cr) to obtain ED- and EA-derived MIL-101(Cr) materials (labeled as MIL-101(Cr)-ED and MIL-101(Cr)-EA), respectively. Then, these three MIL-101(Cr) materials were loaded on the surface of quartz crystal through dip coating to assemble three kinds of MIL-101(Cr)-modified quartz crystal microbalance (QCM) gas sensor, respectively. Moreover, the sensing and recognition performances of these QCM sensors toward methanol, ethanol, 2-propanol, acetone, cyclohexane, diethylamine, formic acid, formaldehyde, ammonia, and acetic acid have been studied in detail. As indicated, MIL-101(Cr)-ED- and MIL-101(Cr)-EA-loaded QCM sensors showed better sensing performance for formic acid in comparison with the original MIL-101(Cr)-based sensor, and the oscillation frequency of these two sensors decreased by 375.6 Hz and 232.1 Hz when the concentration of formic acid was 350 ppm, respectively. ?f value was linearly related to the concentration of formic acid in the range from 5 ppm to 350 ppm. In addition, the sensitivity of MIL-101(Cr)-ED-loaded gas sensor was estimated to be 0.95 Hz·ppm-1 and the limit of detection was 0.95 ppm. As a result, this MIL-101(Cr)-modified QCM gas sensor demonstrated high sensitivity, low detection limit, and good repeatability. In brief, this research would provide some useful information for developing new QCM gas sensors in real-time VOCs detection. As a result, this MIL-101(Cr)-modified QCM gas sensor demonstrated high sensitivity, low detection limit, and good repeatability. In brief, this research would provide some useful information for developing new QCM gas sensors in real-time VOCs detection.

Probing the Size Effect on “Hot Spot” of Au Nanoparticle Dimer-Au Plate Coupling System

ZENG Ziqiang, ZHANG Chenjie, XU Minmin, YAO Jianlin — 2024-04-07 00:00:00.0

The "hot spot" effect has been attracted considerable attention in surface enhanced spectroscopy and relevant fields, especially for the controllable fabrication of the dynamic "hot spot" by using the size and excitation wavelength dependent transfer effect. Herein, the coupling system of spherical dimer of gold nanoparticles and gold plate is theoretically simulated by finite element method (FEM), and the effects of excitation wavelengths and nanoparticle sizes on the electromagnetic field enhancement at different gaps of the system are systematically investigated. The results demonstrated that the two modes of surface plasmon resonance was observed. As the size of nanoparticle is 30 nm and the excitation wavelength is 450 nm~535 nm and 670 nm~950 nm, the two plasmon resonance modes were mainly dominated by a cooperative effect, and “hot spot” mainly located in the particle-particle gap. As the size of nanoparticles was increased to 85 nm or even 105 nm, a competition effect between the two plasmon resonance modes was occurred for the excitation wavelengths of 670 nm~695 nm and 725 nm~755 nm. It resulted in the transformation of “hot spot” from particle-particle to particles-gold plate gaps successfully. It was anticipated that the theoretical simulation provided an alternative approach for control and transfer on the “hot spot” and it was beneficial to design and fabricate the substrate with high performance of surface enhanced optical effect.

Acidic Ionic Liquid Preparation and Its Catalytic Synthesis of Biobased Poly(ethylene 2,5-furandicarboxylate)

ZHOU Qiao, ZHAO Yuanyuan, GUO Liying, SHI Yafei, ZHENG Rongrong — 2024-04-02 00:00:00.0

Five acidic ionic liquid catalysts ([DA-2PS][X]2) were prepared, characterized and tested for their chemical structures, Br?nsted acidity and thermal properties using a fourier transform infrared (FT-IR) spectrometer, a nuclear magnetic resonance instrument (1H NMR), ultraviolet (UV-Vis) spectroscopy, and thermal gravimetric analyser(TGA), replacing conventional metal catalysts to catalyze the direct esterification of 2,5 furanodicarboxylic acid (FDCA) with ethylene glycol (EG) to Poly(ethylene 2,5-furandicarboxylate) (PEF), and the effect of the strength of Br?nsted acidity on the catalytic performance was discussed, in which the [DA-2PS][HSO4]2 with the strongest Br?nsted acidity had the best catalytic performance. The optimum process parameters were investigated by orthogonal tests, the catalyst dosage was 0.10 mol% of the amount of FDCA, the feeding ratio was EG:FDCA=2.0:1, the esterification temperature was 210 ℃, the polycondensation temperature was 240 ℃, and the polycondensation time was 6 h. Experiments were carried out under the optimum process parameters, and the conversion rate of FDCA was 98.1%, the characteristic viscosity of PEF was 0.63 dL·g-1 ,the number average molecular weight of PEF reached 25592g·mol-1. The structural characterization and thermal properties of PEF were tested by fourier transform infrared (FT-IR) spectrometer, a nuclear magnetic resonance instrument (1H NMR), thermal gravimetric analyser(TGA)and differential scanning calorimetry (DSC) analyzer, and the structure of PEF was correct, and it had the comparable thermal properties to those of PEF synthesized by the traditional metal catalysts.

MgCl₂-AlCl₃-EMImBF₄/Organic Ether for Rechargeable Magnesium Battery Electrolytes

WEN Jiaxin, YE Junliu, WEI Xin, YANG Jingdong, YIN Xuejiao, LI Lingjie — 2024-03-29 00:00:00.0

Rechargeable magnesium batteries (RMBs) are considered to be one of the next most promising energy storage systems. The electrolyte has an important influence on the performance of RMBs. The RMBs electrolyte system of MACC-EMImBF4/organic ether was prepared by the addition of EMImBF4 into the MgCl2+AlCl3 electrolyte. The electrochemical performance and full cell performance of the MACCE electrolyte were tested by Cyclic voltammetry (CV), Linear scanning voltammetry (LSV), Electrochemical impedance spectroscopy (EIS), and Galvanostatic charge-discharge curves (GCD). The surface of the electrodes after circulation with MACCE electrolyte were analyzed by Field emission scanning electron microscopy (FE-SEM), X-ray Powder diffractometry (XRD) and X-ray photoelectron spectroscopy (XPS). The results show that the addition of EMImBF4 can effectively improve the electrolyte performance, and the optimum molar concentration ratios of MgCl2-AlCl3 to EMImBF4 is 5:1. MACCE electrolyte has superior electrochemical performances with a high ionic conductivity (~3.94 mS?cm-1), a low overpotential (~59 mV), a high Coulombic efficiency (more than 97.5%), a high anodic stability (~2.8 V, vs. Mg/Mg2+), and a long-term (more than 500 h) cycling stability. The analyses demonstrate that a nanoparticles layer can be formed on the surface of Mg anode during cycling, which is helpful to improve the cycling stability. MACCE displays good compatibility with the Mo6S8 cathode material. Moreover, the Mo6S8|MACCE|Mg full cell delivers a discharge specific capacity of 64.4 mAh?g-1 (12.88 mA?g-1, 0.1 C), which can retain ~73.2% even after 100 cycles. MACCE electrolyte is simple to be prepared, low cost, and can be applied to RMBs, which is of great significance to accelerate the commercial application of RMBs.

Synergistic Effects of Hierarchically Interconnected Porous Structure and Fe Modification on zeolite ZSM-5 for Efficient Benzyl Alcohol Alkylation

2024-03-25 00:00:00.0

Constructing hierarchically porous structure and embedding metal species into zeolite frameworks can effectively enable fast diffusion and synergistic catalysis. We report a one-step synthesis method to synthesize hierarchically macro-meso-microporous zeolite ZSM-5 single crystals containing Fe metal nanoclusters, that has advantages compared to multistep methods such as impregnation and ion exchange. Zeolite ZSM-5-Fe catalysts were prepared by steam-assisted crystallization with the addition of hierarchically porous carbon template and a Fe precursor. The catalyst was systematically characterized by XRD, UV-vis, H2-TPR, and XPS. The results indicated that isolated Fe(III) located at ion exchange sites and aluminum octahedral (six-coordinate) structures were the main redox-active centers. At a loading amount of 1 wt%, the highest benzyl alcohol conversion rate reached 59.3%, with a product selectivity of 83.2%, and a final yield of 49.3%. The catalyst maintained high catalytic activity even after five cycles, demonstrating its remarkable stability.

Recent Advances in Carbon Dots with Near-infrared Absorption/Emission

LIU Yupeng, YANG Junxiang, HAO Yiming, QU Songnan — 2024-03-22 00:00:00.0

Carbon dots are an emerging class of zero-dimensional carbon nano-optical materials that are shining in many fields. Compared with visible light, near-infrared light has deeper tissue penetration and lower scattering and has obvious advantages in fields such as biological imaging. With the exploration of scientific researchers, the regulation of the luminescence band gap of carbon dots has been continuously red-shifted from the initial blue-violet light to longer wavelengths. In recent years, carbon dots with near-infrared absorption/emission have been gradually reported. Based on a series of work of this research group in the near-infrared carbon dots, this review summarizes and reviews the latest progress in preparation strategies and applications of near-infrared carbon dots and prospected the future development directions.

Performance and simulation of dicumyl peroxide synthesis catalyzed by SBA-15 zeolites loaded p-toluenesulfonic acid

Zhang Xiaolong, Zhang Yicheng, LI Qingchao, Zha Fei, CHANG Yue, TANG Xiaohuan — 2024-03-22 00:00:00.0

SBA-15 zeolites loaded p-toluenesulfonic acid (TsOH/SBA-15) were prepared by impregnation method. Its catalytic activity in the formation of dicumyl peroxide (DCP) from α-methylstyrene (α-MS) reacted with isopropylbenzene hydroperoxide (CHP) was tested. The yield of DCP was 62.1% under the dosage of TsOH/SBA-15 was 0.15%, the feed molar ratio of n(α-MS) : n(CHP) was 2, and the reaction temperature and time were 44℃ and 2.5 h. Simulation calculation indicated that the reaction process may have two mechanisms as asynchronous synergistic reaction and step-by-step reaction. α-MS, CHP, and TsOH only need to go through one transition state to complete in asynchronous synergistic reaction while the reactants need to go through two transition states and one intermediate to complete in the step-by-step reaction, both of which involve H+ proton transformation. At 44℃, the ΔG of reaction energy barrier in asynchronous synergistic reaction is 121.8 kJ/mol, while ΔG (TS1)=74.1 kJ/mol and ΔG (TS2)=78.3 kJ/mol for the reaction energy barriers corresponding to the two transition states in the step-by-step reaction.

Rapid Room-temperature Synthesis and Tetracycline Adsorption of Novel Ga-based Metal-Organic Gels

LIU Zhi, GU Junhong, LI Ningning, LIU Zhisheng, LIU Bin, LI Yangxue — 2024-03-22 00:00:00.0

In this research, Ga-based metal-organic gels (Ga-TATB) were synthesized at room temperature through a rapid and simple strategy. Ga-TATB could effectively remove tetracycline (TC) from aqueous solution due to the large specific surface area, unique porous structure and excellent structural stability. The adsorption process of TC by Ga-TATB kept well to the pseudo-second-order kinetic model and the Freundlich isotherm model, and the maximum adsorption capacity could reach 149.92 mg/g at pH = 6.00 and temperature of 25 ℃. Furthermore, the effect of solution pH, Ga-TATB dosage, ionic strength, coexisting inorganic ions, contact time and TC concentration on the adsorption process were systematically investigated, and the possible mechanism of Ga-TATB adsorption towards TC was proposed based on the experimental results. It is worth noting that the strong anti-interference ability and stable reusability make Ga-TATB a good application prospect in tetracycline antibiotic wastewater remediation.

Interaction Between Hot Water Chemical Drive System and Thick Oil Components and Theoretical Simulation Research

HAN Yugui, LIU Changlong, ZHAO Peng, ZHENG Wenwen, LIU Yuepeng, LI Yi — 2024-03-22 00:00:00.0

To investigate the effects of temperature and polymer chemistry on the properties of thick oil, the thick oil fractions were analyzed by scanning electron microscopy, infrared spectrometer apparatus and rheometer. Scanning electron microscopy observed that the asphaltene surface morphology was irregular, and the colloid surface was rough and had a pore structure. Fourier infrared spectroscopy detected three thick oil fractions with characteristic absorption peaks of aromatic hydrocarbons. Rheological performance test was conducted to investigate the effects of polymer chemical addition, mineralization, temperature and pH on the rheological performance and interfacial film properties of thick oil. The experimental results showed that the polymer dosage had a significant effect on the energy storage modulus and loss modulus of the thick oil, while the increase of mineralization enhanced the complex viscosity of the thick oil, and the viscoelasticity of the thick oil was stronger under acidic and alkaline conditions than under neutral conditions. It was found through theoretical studies that the addition of polymer chemistries reduced the viscosity of thick oil and the effect was more pronounced at higher temperatures. The interaction between bitumen and polymer chemicals was the strongest, followed by colloid and the weakest interaction with oil components. The polymer chemical had no significant effect on the radial distribution function of the thick oil components, and mainly affected the thick oil components at the interface. Polymer chemicals and bitumen could form hydrogen bonds, and the addition of polymer chemicals decreased the number of hydrogen bonds within the bitumen and increased the number of hydrogen bonds with the polymer chemicals. The increase of temperature decreased the number of hydrogen bonds, especially between the asphaltene and the polymer chemical.

Continuous Flow Liquid-phase Peptide Synthesis Using Hydrophobic Silyl Tag

LIU Hao, LIU Dongmei, SUN Haotian, XIA Chao, SU Xianbin — 2024-03-20 00:00:00.0

A novel hydrophobic silyl tag bis(4-((tert-butyldiphenylsilyl)oxy)phenyl)methanamine (BPPM) was proposed for rapid liquid-phase peptide synthesis under continuous flow in a microreactor. The designed continuous flow device consists of a coupling unit (micro-channel reactor), a deprotection unit (packed-bed reactor) and a washing unit (micro-channel mixer). In this process, a green solvent (ethyl acetate instead of N,N-dimethylacetamide) and Cbz-protected amino acids (clean deprotection instead of piperidine Fmoc-deprotection) were used. Vialox peptide with high purity (>95% crude) was synthesized in an environmentally friendly way, with high synthesis efficiency (each amino acid per coupling <5min). The results of this work are easy to scale up and provide a new strategy for large-scale green and efficient synthesis of peptides.

Methodologies for the Precise Modification of Guest Molecules by Proteins

DAI Zhen, LIU Yu, LIU Tao — 2024-03-19 00:00:00.0

Precise modification of guest molecules on proteins is a crucial technological foundation for supramolecular modulation of protein activity. This is especially true for aromatic functional group guests containing positive charges, which can be efficiently bound to cucurbituril. However, precise modification of these molecules on proteins using non-canonical amino acid site specific modification technology can be challenging. The linkers of bioorthogonal reactions are often large, which can affect the recognition of the host and guest molecules. To address this issue, the target proteins were modified by adding iodine- or alkynyl-functional amino acids using the non-canonical amino acid site specific modification technology. The pyridine molecules with a positive charge were efficiently bound to cucurbituril molecules using the palladium-catalyzed Suzuki and Sonogashira coupling reaction. Subsequently, a non-natural amino acid with an alkynyl functional group was successfully incorporated into the target proteins using a series of reaction conditions. Furthermore, a Sonogashira coupling reaction was utilized to attach a positively charged pyridine molecule to the protein surface. These accomplishments establish a crucial technological basis for the chemical regulation of proteins through host-guest interactions.

A new method for large-scale enrichment and stepwise identification of RNA-protein complexes

DONG Peiying, LIU Tong, QIN Weijie — 2024-03-16 00:00:00.0

RNA-protein complexes (RPC) regulate various physiological processes in organisms and play a crucial role in the synthesis and degradation of RNA. For deep RPC profiling in addition to develop RNA-Binding Proteins (RBP) enrichment methods, some researchers also turned their attention to RNA-Associated Proteins (RAP), which interact with RBP via protein-protein interaction. However, previous methods often enrich all proteins in the RPC as a whole and cannot differentiate RBP from RAP. Therefore, we reported a new method using combination of 254nm UV crosslinking of RBP and RNA and DSP crosslinking of RBP and RAP. Next, RBP and RAP can be eluted in a stepwise way and separately identified by mass spectrometry. A total of 2007 high confidence RBP and 927 high confidence RAP were identified in HeLa cells, of which 243 RAP were identified for the first time. This method aims to refine the RNA-protein interaction network and provide a favorable foundation for subsequent biological investigations.

Research on the Preparation of Efficient and Stable Perovskite Solar Cells Based on Amino Acid Derivative Hydrochloride Additives

HU Die, SUN Qing, MENG Xiangxin, LING Jinxiang, CHENG Bin, KANG Bonan — 2024-03-14 00:00:00.0

The rapid development of perovskite solar cells (PSCs) has made them one of the most competitive photovoltaic devices in the field of new energy. However, there is still great room for improvement in photoelectric conversion efficiency (PCE) and stability. Here, an amino acid derivative hydrochloride is introduced as an additive in perovskite, D-phenylglycine methyl ester hydrochloride (PGMECl). PGMECl contains a benzene ring, an ester group, -NH3+ terminal and Cl- ions. Multiple functional groups work together to react with uncoordinated Pb2+, passivating defects in perovskite. The perovskite grains become denser, surface roughness decreases, and non-radiative recombination of charge carriers is reduced. By adjusting the energy level arrangement, it is more suitable for charge transfer in inverted perovskite solar cells. The results show that the champion PCE of PGMECl modification device is 21.04%, which is much higher than that of control devices (17.79%). The decrease in hysteresis effect also indicates a decrease in ion migration. Under unencapsulated conditions, devices containing PGMECl additives can still maintain a PCE of 70% of the initial efficiency after aging in the dark in air (40 ± 5% relative humidity (RH)) for 1000 hours, while the efficiency of the basic device decreases to 50% after 500 hours of storage.

Preparation of FAU Zeolite Membrane Using Nanoseeds and Its Pervaporation Mechanism and Prediction of Separation Performance

WANG Qing, XU Nong, LIU Qiao, GUO Yu, WANG Bin, HU Kunhong, ZHOU Rongfei — 2024-03-12 00:00:00.0

FAU zeolite membranes were prepared on α-alumina supports using two types of seeds (i.e., 50 nm and 0.7~1.4 μm), respectively. The microstructures, morphologies, and separation performance of membranes were characterized by XRD, SEM, and pervaporation (PV). Compared with FAU membranes prepared using micro-seeds (0.7~1.4 μm), nano-seeds (50 nm) have higher activity, which could promote the rapid growth of the membrane layer and prepare pure-phase, defect-free, and high-performance versions. Subsequently, the separation mechanism of the nano-seed-derived FAU membrane was investigated through the relationship between the single-gas permeation, PV performance, and polarity index (affinity). The results demonstrate that single-gas permeation exhibited Knudsen selectivity; however, the PV performance had a good correlation with the polarity index, which indicates that the PV process through the FAU membrane was controlled by the adsorption-diffusion mechanism. Furthermore, this good correlation provides a novel, convenient, and environmentally friendly tool for predicting PV performance. FAU membranes had good reproducibility, excellent stability, and high PV dehydration performance and were expected to play a great role in organic solvent dehydration.

Study on Light Release and Antioxidant Activity of Avobenzone-Ferulic Acid (AB-FA)

ZHANG tianlong, CHEN guang — 2024-03-12 00:00:00.0

Ferulic acid is an effective antioxidant that is widely used in the cosmetics owing to its ability to resist oxidative stress and delay skin aging. However, its photosensitivity challenges its application. In order to overcome this limitation, we developed a binary molecule composed of avobenzone (AB) and ferulic acid (FA). This design is based on the existence of photoremovable benzoyl methyl in the avobenzone to protect ferulic acid from photodamage and maintain its antioxidant activity. The results showed that FA was successfully released, and AB had an effectively photoprotective effect on FA. In vitro experiments show that AB-FA molecules and their photolysis products have significant activity of scavenging free radical, while cell experiments confirm their low cytotoxicity and excellent ability to scavenge ROS scavenging.

Research progress on the molecular structure of amorphous chalcogen elements

SHI Wuyi, BAO Yu, CUI Shuxun — 2024-03-12 00:00:00.0

Chalcogen elements (including sulfur, selenium, and tellurium) are essential substances in the nature and have wide-range applications in photoelectric materials, batteries, semiconductors, and other fields. Chalcogen elements have two structural forms: crystalline and amorphous. While the molecular structure of crystalline chalcogen elements has been extensively investigated, the molecular structures of amorphous chalcogen elements remain uncertain. To better explore the potential applications of amorphous chalcogen elements, it is necessary to study their structure and properties. This paper summarizes recent advancements in understanding the molecular structure of amorphous chalcogen elements and envisages potential research directions. These efforts aim to contribute to a more comprehensive understanding of the properties of amorphous chalcogen elements and to foster their application across diverse fields.

Photoinduced Trifluoromethyl/Arylation Reaction of Double Bond involving CF3Br for the Synthesis of CF3-Substituted 1,1-Diaryl Alkane Derivatives

MA Ransong, BI Jili, HU Yulai — 2024-03-12 00:00:00.0

A synergistic catalytic strategy combining photocatalysis and transition metal catalysis was employed to achieve the double bond trifluoromethyl/arylation reaction in which the inexpensive and readily available bromotrifluoromethane and aromatic amines were used as substrates. A series of potentially biologically active CF3-substituted 1,1-diaryl alkane derivatives were synthesized. This job explores the possibility of aromatic amines as arylation reagents, enriches the types of arylation reagents, clarifies the conditions for the arylation process and explores the reaction mechanism. This method has the characteristics of simple operation, low cost and easy availability, providing a concise and effective approach for the synthesis of trifluoromethyl substituted 1,1-diaryl alkanes derivatives.

Influence of Interface Adsorption on the Dewetting Kinetics of Polymer Liquid Films

ZHANG Yining, WEI Lai, SHI Tongfei, XU Lin — 2024-03-12 00:00:00.0

Widely used in coatings, optoelectronic devices, and sensing devices, polymer films have broad applications, with their interface stability being a key factor significantly affecting these applications. During their application, these films require stability not only in air but also under various environmental conditions, including in water or organic solvents. To date, the systematic elucidation of the influence of solvent-restricted interface adsorption of polymer films on their stability has not been fully explored. In this work, focusing on linear polystyrene (LPS) films and 3-arm star-shaped polystyrene (3SPS) films, we explored the influence of polymer chain interface adsorption in confined systems on the interfacial stability of polymer solution films. We found in our experimental results that the polymer chains adsorbed on the substrate form a drag force, which drives the dewetting of the film and increases the resistance to film dewetting. As the annealing time increases, the adsorption of linear and 3-arm star-shaped chains on the substrate gradually increases; LPS and 3SPS films transition from dewetting to stable existence in acetone vapor, with the edge becoming stable during the film dewetting process, the dewetting speed gradually decreasing, and the equilibrium contact angle progressively decreasing. At the same annealing time, 3SPS films exhibit a lower dewetting speed in acetone vapor than LPS films, and after dewetting, 3SPS films on the substrate have a smaller equilibrium contact angle than LPS films, indicating that the capillary driving force of 3SPS films is less than that of LPS films.

Room Temperature Driven Sodium Humate-protected Carbon Nanoclusters for Fluorescent and Colorimetric Sensing of Ag+ and Temperature

LI Lin, MA Jing, XU Changlin, CHEN Tongyao, GUO Hengyao, LI Ziyou, WU Wenxin — 2024-03-12 00:00:00.0

Based on hydrogen bonding self-assembly strategy, hypotoxicity and water-soluble cyan fluorescent carbon nanoclusters (HAN-CNCs) were successfully constructed employing a highly-efficient green economy and room temperature synthesis method, which used ascorbic acid and high biocompatibility coal-based sodium humate with abundant hydroxy as raw materials. The as-prepared HAN-CNCs can be specifically quenched by Ag+ at pH 5.0, with a wide detection range (0-300 μM) and a low detection limit of 27.5 nM. It was found that Ag+ can induce fluorescence static quenching of the HAN-CNCs, owing to the coordination interaction between Ag+ and amine groups or carbonyl group on the surface of HAN-CNCs. More interestingly, the colorimetric detection of Ag+ could be additionally realized by visible color conversion (yellowish-rubricans) under the daylight and the cyan fluorescence gradually changed to blue purple under ultraviolet lamp. From this, the HAN-CNCs was employed in fabrication portable test strip for colorimetry monitoring of Ag+ via the red-green-blue (RGB) analysis with the linear range of 0-150 μM. In addition, HAN-CNCs exhibit excellent reversible thermal response in the range of 20 °C to 85 °C and has potential as a temperature sensor. Furthermore, the HAN-CNCs exhibited low biotoxicity and excellent cell permeability when selectively detecting Ag+ in living cells by fluorescence microscopy imaging, indicating that the sensing system can be effectively applied to assess potential risks and health security.

[超分子纳米药物递送系统] Research Progress in Nanomaterial-Induced Cuproptosis in Tumor Cells

HE Kuo, DING Binbin, MA Ping’an, LIN Jun — 2024-02-21 00:00:00.0

Nanomaterials are considered as a promising cancer treatment method by selectively inducing programmed cell death (PCD) of tumor cells. Cuproptosis is a newly discovered PCD pattern caused by intracellular copper ion overload, characterized by the aggregation of acylated mitochondrial enzymes and the loss of Fe-S proteins. Various nanomaterials have been developed to induce cuproptosis in tumor cells as a treatment for cancer. Numerous studies have demonstrated that cuproptosis achieves better anti-tumor effects when combined with other tumor therapeutic modalities, showing a great potential. This paper introduces the mechanisms and characteristics of cellular cuproptosis, outlines the strategies and mechanisms of nanomaterial-induced cuproptosis in tumor cells, focuses on classifying and outlining the recent research progress of nanomaterial-induced cuproptosis combination therapy, and looks forward to the future prospects of this emerging therapeutic modality.

Nitrogen-doped Carbon Material MG-T Heterogeneous Catalyzed Hydrogenation of Nitrobenzene to Aniline

2024-02-19 00:00:00.0

Aniline, as an important chemical intermediate, is mainly prepared by catalyzing the hydrogenation of nitrobenzene. In this study, a sacrificial template MCA was prepared using melamine and cyanuric acid, and the precursor MG was synthesized using glucose as the carbon source, and nitrogen-doped carbon material MG-T(T denotes the carbonation temperature(℃)) was obtained by high-temperature carbonization, which was used in the heterogeneous catalytic nitrobenzene hydrogenation to aniline reaction. A preliminary study of the reaction mechanism was carried out by combining the results of material characterisation and catalytic evaluation. The experimental results indicated that the carbonisation temperature affects the change of nitrogen species configuration in MG-T, and the graphitic nitrogen plays a key role in the hydrogenation activity of the catalysts. The catalyst MG-800 reacted in ethanol solvent with hydrazine hydrate as the reducing agent at 80 ℃ for 4 h. The conversion of nitrobenzene was 96%, the product selectivity was 100%, and the catalyst could be recycled at least 9 times, with good stability and recyclability, which is a class of recyclable heterogeneous catalysts for the hydrogenation of nitrobenzene to aniline.

Research Progress in Efficient Azide Methods

LONG Lei, WEI Wei, LUO Yunjun, LI Xiaoyu — 2024-02-19 00:00:00.0

Organic azide compounds are a class of multifunctional compounds that are useful precursors for synthesizing a range of therapeutic drugs, bioactive compounds, functional materials, and high-energy compounds. They are widely used in click chemistry and Staudinger reactions. In the past few decades, a large number of synthesis strategies have been developed to prepare structurally diverse organic azides, but not all reactions can be carried out efficiently. As the concept of green chemistry deepens in people's hearts, traditional azide methods with low safety, universality, and efficiency are gradually being phased out, and the development of new and efficient azide methods is urgent. This review focuses on the efficient synthesis methods for preparing aliphatic azide compounds and azide polymers in recent years. A brief overview of the synthesis of aliphatic azide compounds is provided from the azide strategies of C-C multiple bonds and C-H bonds. The synthesis methods and potential novel synthesis strategies of azide polymers are also discussed, and the future development of azide chemistry is summarized and discussed.