251 results match your criteria: "National Demonstration Center for Experimental Chemistry Education[Affiliation]"

The broad employment of clean hydrogen through water electrolysis is restricted by large voltage requirement and energy consumption because of the sluggish anodic oxygen evolution reaction. Here we demonstrate a novel alternative oxidation reaction of green electrosynthesis of valuable 3,3'-diamino-4,4'-azofurazan energetic materials and coupled with hydrogen production. Such a strategy could greatly decrease the hazard from the traditional synthetic condition of 3,3'-diamino-4,4'-azofurazan and achieve low-cell-voltage hydrogen production on WS/Pt single-atom/nanoparticle catalyst.

View Article and Find Full Text PDF

N-doped molybdenum oxide quantum dots as fluorescent probes for the quantitative detection of copper ions in environmental samples.

Anal Methods

November 2023

State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, National Demonstration Center for Experimental Chemistry Education, School of Chemistry and Chemical Engineering, Ningxia University, Yinchuan, 750021, China.

A novel, sensitive, and selective fluorescence sensor based on N-doped Mo oxide quantum dots (N-MoOx QDs) was fabricated for the detection of Cu ions in water. The presence of Cu induced dynamic fluorescence quenching of the N-MoOx QDs. The sensing conditions were optimized to enhance selectivity and sensitivity.

View Article and Find Full Text PDF

Rapid Analysis of Squalene, Tocopherols, and Sterols in Walnut Oils Based on Supercritical Fluid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry.

J Agric Food Chem

November 2023

Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, National Demonstration Center for Experimental Chemistry Education, Northwest University, Xi'an, Shaanxi 710127, People's Republic of China.

Quantification of liposoluble micronutrients in large-scale vegetable oil samples is urgently needed, because their health benefits are increasingly emphasized. However, current analytical methods are limited to either labor-intensive preparation processes or time-consuming chromatography separation. In this work, an online oil matrix separation strategy for direct, rapid, and simultaneous determination of squalene, tocopherols, and phytosterols in walnut oil (WO) was developed on the basis of the lipid class separation mode of supercritical fluid chromatography.

View Article and Find Full Text PDF

Synthesis of pH-Sensitive Nitrogen-Doped Carbon Dots with Biological Imaging Function and Their Application in Cu and Fe Determination by Ratiometric Fluorescent Probes.

ACS Omega

October 2023

Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, National Demonstration Center for Experimental Chemistry Education, Henan Engineering Laboratory for Bioconversion Technology of Functional Microbes, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, P. R. China.

pH-sensitive nitrogen-doped carbon dots (N-CDs) were synthesized using immature seeds of elm trees as a carbon source and ethylenediamine as a coreactant through a facile one-step hydrothermal method. The N-CDs were characterized using fluorescence spectroscopy, fluorescence lifetime, ultraviolet-visible absorption, X-ray photoelectron spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy, as well as transmission electron microscopy. The N-CDs displayed excellent fluorescence properties and responded to pH changes.

View Article and Find Full Text PDF

Scandium-Catalyzed Electrochemical Synthesis of α-Pyridinyl Tertiary Amino Acids and Esters.

Org Lett

October 2023

Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, National Demonstration Center for Experimental Chemistry Education, Nanjing University, Nanjing 210023, China.

α-Pyridyl tertiary amino acids have potential pharmaceutical applications because of their structural features. However, their synthesis is still highly limited. Herein, we report a straightforward approach for the electrochemical synthesis of tertiary α-substituted amino acid derivatives via three-component reductive coupling.

View Article and Find Full Text PDF

Gut microbiome and brain transcriptome analyses reveal the effect of walnut oil in preventing scopolamine-induced cognitive impairment.

Food Funct

October 2023

Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, National Demonstration Center for Experimental Chemistry Education, Northwest University, Xi'an, Shaanxi 710127, China.

Article Synopsis
  • Walnut Oil (WO) might help improve thinking skills, but scientists are still figuring out how it works.
  • In a study with mice, taking WO for 8 weeks helped stop problems with their brains caused by a chemical called scopolamine.
  • The researchers found that WO changes some brain chemicals and gut health, which helps the brain work better.
View Article and Find Full Text PDF

Characterization and metabolism pathway of volatile compounds in walnut oil obtained from various ripening stages via HS-GC-IMS and HS-SPME-GC-MS.

Food Chem

March 2024

Key Laboratory of Synthetic and Natural Functional Molecule of Ministry of Education, College of Chemistry and Materials Science, National Demonstration Center for Experimental Chemistry Education, Northwest University, Xi'an, Shaanxi 710127, China. Electronic address:

Volatile organic compounds (VOCs) of walnut oil (WO) samples obtained from 5 ripening stages were analyzed by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and HS-solid phase microextraction-GC-mass spectrometry (HS-SPME-GC-MS). A total of 75 VOCs were identified in WO, of which 24 VOCs were found to be the key aroma-active compounds for WO by using odor activity values (OAVs) analysis. Based on chemometrics methods, flavor of WO samples can be characterized into three categories, i.

View Article and Find Full Text PDF

Strong Bioactive Glass-Based Hybrid Implants with Good Biomineralization Activity Used to Reduce Formation Duration and Improve Biomechanics of Bone Regeneration.

Polymers (Basel)

August 2023

The Key Laboratory for Surface Engineering and Remanufacturing in Shaanxi Province, School of Chemical Engineering, Xi'an University, Xi'an 710065, China.

Developing bioactive implants with strong mechanical properties and biomineralization activity is critical in bone repair. In this work, modified cellulose nanofiber (mCNF)-reinforced bioactive glass (BG)-polycaprolactone (PCL) hybrids (mCNF-BP) with strong biomechanics and good apatite formation ability were reported. Incorporating mCNFs shortens the forming duration of the hybrid films and enhances the biomechanical performance and in vitro apatite-formation capability.

View Article and Find Full Text PDF

Palladium/Lewis Acid Co-catalyzed Cyclocarbonylation of (2-Aminoaryl)(aryl)methanols: An Access to 3-Aryl-indolin-2-ones.

J Org Chem

September 2023

Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, National Demonstration Center for Experimental Chemistry Education, College of Chemistry & Materials Science, Northwest University, 1 Xuefu Road, Xi'an, Shaanxi 710127, P. R. China.

A benign approach to valuable 3-aryl-indolin-2-ones was developed based on palladium(II)/Lewis acid-cocatalyzed cyclocarbonylation of readily available (2-aminoaryl)(aryl)methanols. The protocol features producing water as the only byproduct, mild reaction conditions, and good efficiency, constituting an array of 3-arylindolin-2-ones in yields of 35 to 90%. The reaction can be easily scaled up to the gram scale in good yields.

View Article and Find Full Text PDF

Preparation of Oxygen-Doping Nongraphitic Carbon Nitride via Efficiency Exfoliation for the Application of Photocatalytic Degradation.

Langmuir

August 2023

State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, National Demonstration Center for Experimental Chemistry Education, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, P. R. China.

E-OLCN photocatalyst was synthesized by oxygen doping of low molecular weight carbon nitride (LCN) with ethanol solvent stripping. The enhanced light absorption, fast electron transport rate, and photogenerated carrier separation efficiency of E-OLCN leads to the excellent photocatalytic degradation performance compared with the original materials. The synergistic effect of oxygen doping and ethanol solvent stripping plays a significant role for the modulation of electronic and structural properties of the prepared catalysts.

View Article and Find Full Text PDF

Enhancing photocatalytic overall water-splitting performance on dual-active-sites of the Co-P@MoS catalysts: a DFT study.

Phys Chem Chem Phys

August 2023

State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering, National Demonstration Center for Experimental Chemistry Education, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China.

The rational construction of photocatalysts possesses tremendous potential to solve the energy crisis and environmental pollution; however, designing a catalyst for solar-driven overall water-splitting remains a great challenge. Herein, we propose a new MoS-based photocatalyst (Co-P@MoS), which skillfully uses the cobalt (Co) atom to stimulate in-plane S atoms and employs the phosphorus (P) atom to stabilize the basal plane by forming the Co-P bands. Using density functional theory (DFT), it was found that oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) can occur at the P site and S2 site of the Co-P@MoS, respectively, and the dual-active sites successfully makes a delicate balance between the adsorption and dissociation of hydrogen.

View Article and Find Full Text PDF

Characterization of Type I/II g-CN/MoS van der Waals Heterostructures: A New Theoretical Insight.

J Chem Inf Model

August 2023

State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, National Demonstration Center for Experimental Chemistry Education, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, China.

The charge transfer mechanism of the g-CN/MoS heterojunction is still disputed. Some regard it as a type I pathway, some regard it as a type II pathway, and still some regard it as a Z-scheme pathway. Especially, the results obtained by density functional theory (DFT) calculations are not totally in agreement.

View Article and Find Full Text PDF

Design, Synthesis and Characterization of Palladium-Functionalized Covalent Organic Framework and Its Application as Heterogeneous Catalysis for C-H Arylation of Azoles.

Chemistry

August 2023

Hebei Key Laboratory of Organic Functional Molecules, National Demonstration Center for Experimental Chemistry Education, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang, 050024, P. R. China.

A novel triazine-based covalent organic framework (TFPT-Bz COF) has been constructed by the condensation of 2,4,6-tris(5-formyl-2-pyridinoxy)-1,3,5-triazine (TFPT) and benzidine (BZ) with deep eutectic solvent (DES) as the reaction medium. After the introduction of Pd ions through strong coordination to TFPT-Bz COF matrix, the constructed TFPT-Bz COF/Pd composite exhibited excellent catalytic activity for C-H arylation of azoles with aryl halides in 2-methyltetrahydrofuran. The protocol allows the arylation of a variety of substituted azoles with diverse aryl halides in high to excellent yield.

View Article and Find Full Text PDF

Multi-dimensional deep learning drives efficient discovery of novel neuroprotective peptides from walnut protein isolates.

Food Funct

July 2023

Beijing Key Laboratory of Food Processing and Safety in Forestry, Department of Food Science and Engineering, College of Biological Sciences and Biotechnology, Beijing Forestry University, 100083 Beijing, People's Republic of China.

Neurodegenerative diseases, such as Alzheimer's and Parkinson's, are multi-factor induced neurological disorders that require management from multiple pathologies. The peptides from natural proteins with diverse physiological activity can be candidates as multifunctional neuroprotective agents. However, traditional methods for screening neuroprotective peptides are not only time-consuming and laborious but also poorly accurate, which makes it difficult to effectively obtain the needed peptides.

View Article and Find Full Text PDF

A red fluorescence probe for reversible detection of HSO/HO and its application in food samples and bioimaging.

Spectrochim Acta A Mol Biomol Spectrosc

October 2023

College of Laboratory Medicine, Dalian Medical University, Dalian 116044, China. Electronic address:

Reducing agent SO and oxidant HO are two essential substances in cells, and the balance between them is closely related to the survival of cells. SO derivative HSO is often used as food additive. Therefore, simultaneous detection of SO and HO is of great significance in biology and food safety.

View Article and Find Full Text PDF

An aptamer-functionalized photonic crystal sensor for ultrasensitive and label-free detection of aflatoxin B1.

Talanta

August 2023

College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Nankai University, Tianjin, 300071, China; Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116011, China. Electronic address:

As a novel optical responsive material, photonic crystal is a promising sensing material in the recognition and detection of small molecules. Herein, a label-free composite sensor for aflatoxin B1 (AFB1) based on aptamer-functionalized photonic crystal arrays was successfully developed. Three-dimensional photonic crystals (3D PhCs) with a controllable number of layers were produced by a layer-by-layer (LBL) approach, and the introduction of gold nanoparticles (AuNPs) facilitated the immobilization procedure of recognition element aptamers, thus creating the AFB1 sensing detection system (AFB1-Apt 3D PhCs).

View Article and Find Full Text PDF

Amelioration of walnut-derived novel peptides against D-galactose-induced cognitive impairment by modulating the gut microbiota composition.

Food Funct

May 2023

Beijing Key Laboratory of Food Processing and Safety in Forestry, Department of Food Science and Engineering, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.

In this work, RLWPF (Arg-Leu-Trp-Pro-Phe) and VLRLF (Val-Leu-Arg-Leu-Phe) were investigated for the effects against D-galactose (D-gal) induced cognitive impairment by modulating the gut microbiota composition. The effects on serum metabolite production were further investigated. The two novel peptides derived from walnut protein alkaline protease hydrolysates were predicted by docking to acetylcholinesterase (AChE) with the highest binding affinities, -10.

View Article and Find Full Text PDF

Detection of walnut oil adulterated with high-linoleic acid vegetable oils using triacylglycerol pseudotargeted method based on SFC-QTOF-MS.

Food Chem

August 2023

Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, National Demonstration Center for Experimental Chemistry Education, Northwest University, Xi'an, Shaanxi 710127, China. Electronic address:

Authentication of walnut oil (WO) is challenging due to the adulteration of high-linoleic acid vegetable oils (HLOs) with similar fatty acid composition. To allow the discrimination of WO adulteration, a rapid, sensitive and stable scanning method based on supercritical fluid chromatography quadrupole time-of-flight mass spectrometry (SFC-QTOF-MS) was established to profile 59 potential triacylglycerol (TAGs) in HLOs samples within 10 min. Limit of quantitation of the proposed method is 0.

View Article and Find Full Text PDF

Construction of Stable Magnetic Vinylene-Linked Covalent Organic Frameworks for Efficient Extraction of Benzimidazole Fungicides.

ACS Appl Mater Interfaces

March 2023

College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Nankai University, Tianjin 300071, China.

Covalent organic frameworks (COFs) have attracted impressive interest in separation on aqueous media. Herein, we integrated the stable vinylene-linked COFs with magnetic nanosphere via the monomer-mediated in situ growth strategy to construct a crystalline FeO@v-COF composite for enrichment and determination of benzimidazole fungicides (BZDs) from complex sample matrices. The FeO@v-COF has a crystalline assembly, high surface area, porous character together with a well-defined core-shell structure, and serves as progressive pretreatment materials for magnetic solid phase extraction (MSPE) of BZDs.

View Article and Find Full Text PDF

Facile and Green Synthesis of Carbon Dots from Melia Azedarach Leaves for pH Sensing and Cell Imaging.

J Fluoresc

September 2023

Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, National Demonstration Center for Experimental Chemistry Education, Henan Engineering Laboratory for Bioconversion Technology of Functional Microbes, School of Chemistry and Chemical Engineering, College of Life Science, Henan Normal University, Xinxiang, 453007, People's Republic of China.

Carbon dots (CDs) have preeminent application prospects as a new star in the nanomaterials field. In this work, a green and facile method to synthesize the blue-emitting CDs was proposed with Melia azedarach leaves as the carbon precursors. Using nature materials without other expensive reagents and instruments, the processes were simple and environmental-friendly.

View Article and Find Full Text PDF

Competitive ELISA based on pH-responsive persistent luminescence nanoparticles for autofluorescence-free biosensor determination of ochratoxin A in cereals.

Anal Bioanal Chem

April 2023

State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering, National Demonstration Center for Experimental Chemistry Education, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan, 750021, China.

An accurate and sensitive competitive enzyme-linked immunosorbent assay (ELISA) based on persistent luminescence nanoparticles ZnGeO:Mn, Eu (ZGME) was developed for detecting ochratoxin A (OTA), a powerfully toxic mycotoxin usually found in grains. As a signal output element of autofluorescence-free biosensors, ZGME can be integrated into ELISA with glucose oxidase (GOx)-binding OTA molecules due to its excellent pH-responsive persistent luminescence. In the absence of OTA, the OTA-GOx conjugate was captured by the anti-OTA monoclonal antibody (anti-OTA mAb) pre-coated on the 96-well plate.

View Article and Find Full Text PDF

Bio-Inspired FeMoS Microspheres as Bifunctional Electrocatalysts for Boosting Hydrogen Oxidation/Evolution Reactions in Alkaline Solution.

ACS Appl Mater Interfaces

March 2023

Hebei Key Laboratory of Organic Functional Molecules, National Demonstration Center for Experimental Chemistry Education, Hebei Key Laboratory of Inorganic Nanomaterials, Testing and Analysis Center, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang, Hebei 050024, P. R. China.

Developing robust and effectual nonprecious electrocatalysts for the bifunctional hydrogen oxidation and evolution reactions (HOR and HER) in alkaline electrolyte is of critical significance for the realization of future hydrogen economy but challenging. Herein, this work demonstrates a new routine for the preparation of bio-inspired FeMoS microspheres the one-step sulfuration of Keplerate-type polyoxometalate {MoFe}. The bio-inspired FeMoS microspheres feature potential-abundant structural defects and atomically precise iron doping and act as an effective bifunctional electrocatalyst for hydrogen oxidation/reduction reactions.

View Article and Find Full Text PDF

Micron-Scale Fabrication of Ultrathin Amorphous Copper Nanosheets Templated by DNA Scaffolds.

J Am Chem Soc

March 2023

School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Institute of Translational Medicine, Shanghai Jiao Tong University, Shanghai 200240, China.

Two-dimensional (2D) amorphous materials could outperform their crystalline counterparts toward various applications because they have more defects and reactive sites and thus could exhibit a unique surface chemical state and provide an advanced electron/ion transport path. Nevertheless, it is challenging to fabricate ultrathin and large-sized 2D amorphous metallic nanomaterials in a mild and controllable manner due to the strong metallic bonds between metal atoms. Here, we reported a simple yet fast (10 min) DNA nanosheet (DNS)-templated method to synthesize micron-scale amorphous copper nanosheets (CuNSs) with a thickness of 1.

View Article and Find Full Text PDF

Three-Component Domino Reaction of Thioamide, Isonitriles, and Water: Selective Synthesis of 1,2,4-Thiadiazolidin-3-ones and ()--(1,2-Diamino-2-thioxoethylidene)benzamides.

J Org Chem

June 2024

The State Key Laboratory of Applied Organic Chemistry, and College of Chemistry and Chemical Engineering, Lanzhou University, 222 Tianshui Road, Lanzhou 730000, P. R. China.

The three-component domino reaction of thioamides, benzyl isocyanide, and water in the presence of a catalytic amount of both Pd(dppf)Cl and Cu(OAc) afforded novel 1,2,4-thiadiazolidin-3-one cyclic compounds, whereas the same reaction with tertiary alkylisonitriles in the presence of rare earth metal salt [La(OTf)] resulted in ()--(1,2-diamino-2-thioxoethylidene)benzamide open-chain products. This divergent reaction enabled the one-pot construction of five (N-S, C-S, C-O, and two C-N) or four (C-S, C-N, C-O, and C-C) new chemical bonds. Mechanism studies indicate that the oxygen atom of the product was derived from HO.

View Article and Find Full Text PDF

Direct Z-scheme heterojunction Bi/BiS/α-MoO photoelectrocatalytic degradation of tetracycline under visible light.

Chemosphere

February 2023

State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, PR China. Electronic address:

A hot research topic in visible-light-driven photoelectrocatalytic (PEC) oxidation technology is the development of superior photoanode materials. The design of the photoanode system with a direct Z-scheme charge transfer mechanism is crucial to achieving effective charge separation for sustainable photoelectrocatalysis. Here, a novel Bi/BiS/α-MoO heterostructure was successfully assembled by a simple and feasible strategy.

View Article and Find Full Text PDF