查找使用阿拉丁产品的科研文献

γ-aminobutyric acid (GABA) treatment alleviates off-flavor in postharvest waxed citrus fruit by enhancing peel gas permeance

Zhiquan Wang,Junchao Wang,Lu Qin,Zhen Huang,Xinxin Xu,Zhifeng Zhu,Jingjie Tang,Xiaojie Cui,Rangwei Xu,Feng Zhu,Yanping Fu,Xiuxin Deng,Quan Sun,Yunjiang Cheng

Postharvest wax coating reduces water loss and enhances visual appeal but impairs gas exchange in citrus fruit, inducing anaerobic fermentation and off-flavor development. This study demonstrates that exogenous γ-aminobutyric acid (GABA) mitigates these physiological disorders. GABA enhanced peel gas permeance by 1.7- to 2.2-fold through suppression of C25-C31 cuticular alkane biosynthesis and enlargement of stomatal apertures, thereby alleviating internal hypoxia. This metabolic shift from anaerobic fermentation toward aerobic respiration was mediated by GABA shunt reprogramming and amino acid metabolic remodeling, which reduced ethanol accumulation by 57% while preserving key flavor compounds. Transcriptomic analysis revealed coordinated regulation of genes associated with wax synthesis, fermentation, and hypoxia responses. This simple amino acid treatment preserves citrus fruit flavor and nutritional quality under waxing-induced hypoxia by mitigating physiological disorders.

Boosting CO2 separation from flue gas through two-dimensional interface engineering of MOFs promoters via hydrate-based method

Fang Wang,Jixin Dong,Jinchi Mu,Xiaosheng An,Jiandong Chen,Shuai Leng,Ying Zhou

Hydrate-based technology offers an environmentally friendly and energy-efficient route for CO 2 capture from flue gas, but its practical application is hindered by slow kinetics, high compression energy demand and limited separation efficiency. To address these challenges, this study introduces three-dimensional (3D) nanoporous metal-organic frameworks (MOFs) as kinetic promoters for enhanced CO 2 capture from the simulated flue gas (20% CO 2 /80% N 2 ). Particularly, we functionalize 3D MIL-100(Fe) with 2D boron nitride oxide (BNO) to construct a BNO/MIL-100(Fe) 2D/3D hybrid architecture featuring substantially enhanced specific surface area and optimized pore characteristics. Compared to unmodified MIL-100(Fe), 2D Ni/Fe layered double hydroxide (Ni/Fe-LDH), graphitic carbon nitride (g-C 3 N 4 ) and one-dimensional (1D) multi-walled carbon nanotubes (MWCNTs), the BNO/MIL-100(Fe) hybrid exhibits superior kinetic promotion performance, owing to the specific surface area as high as 1001.81 m 2 /g and tailored porosity that facilitate efficient CO 2 mass transfer and provide abundant nucleation sites, thereby accelerating hydrate formation. Consequently, the induction time is shortened by approximately 51% compared with pure tetrahydrofuran in the control group and the overall CO 2 hydrate growth is significantly accelerated. Under a low operating pressure of 2.5 MPa and at 275 K, BNO/MIL-100(Fe) achieves a CO 2 storage capacity of 3.99 mmol CO 2 /mol H 2 O and a high separation efficiency of 82.57%, substantially outperforming most reported hydrate-based promoters. This work highlights the strong potential of MOF-based kinetic promoters and provides new insights into the design of advanced materials that integrate 2D modifiers with 3D nanoporous frameworks for efficient CO 2 separation.

Foam stabilized by SiO2/AOS adsorbed at the gas–liquid interface: influence of the degree of nanoparticle modification

Jiali Wang,Zhongbin Ye,Nanjun Lai,Yuaojie Huang,Hongwei Xu

Flame-retardant polybenzoxazine nanocomposites with suppressed smoke and toxic gas emission enabled by copper-embedded laser-induced graphene

Li Jia,Yanan Zhang,Jinyue Dai,Yonggang Wu,Jingkai Liu,Xiaoqing Liu

The development of polymeric materials that integrate both flame retardancy and smoke suppression is crucial for upgrading fire protection level. Traditional flame-retardant methods generally introduce special elements or form intumescent carbon, which exacerbate the release of toxic smoke. Herein, a nanocomposite derived from daidzein-based benzoxazines (Dz-f) and nano-smoke suppressants (Cu@LIG) is reported, which enables the formation of a dense char barrier and facilitates the complete oxidation of carbon monoxide during combustion. Specifically, Cu@LIG features copper-embedded graphene structure was synthesized via laser-induced graphene technology using a polybenzoxazine precursor containing copper(II) acetylacetonate. This material was incorporated into Dz-f matrix via solvent-assisted molding to form a nanocomposite. With only 0.75 wt% Cu@LIG, the composite maintained good thermal stability, mechanical property, and fire safety, while significantly improving smoke suppression performances. It not only achieved a UL-94 V-0 rating and reduced total heat release from 65.4 to 60.9 MJ/m 2 . Furthermore, the maximum smoke density also decreased from 178.7 to 104.9, and the CO production was lowered by 16.3%. Mechanistic studies indicate that the copper species in Cu@LIG catalyze the oxidation of CO to CO 2 and participate in forming a dense char layer in the condensed phase. This work provides an effective strategy for balancing flame retardancy and smoke suppression and offers insights for designing advanced nano smoke suppressants.

W18O49 nanorods decorated with Ag/AgCl nanoparticles as highly-sensitive gas-sensing material and visible-light-driven photocatalyst

Shibin Sun,Xueting Chang,Lihua Dong,Yidong Zhang,Zhenjiang Li,Yanyan Qiu

A novel gas-sensing material and photocatalyst was successfully obtained by decorating Ag/AgCl nanoparticles on the W 18 O 49 nanorods through a clean photochemical route. The as-prepared samples were characterized using combined techniques of X-ray diffractometry, electron microscopy , energy dispersive X-ray spectrometry , and X-ray photoelectron spectroscopy. Gas-sensing measurements indicate that the Ag/AgCl/W 18 O 49 NRs sensors exhibit superior reducing gas-sensing properties to those of bare W 18 O 49 NRs, and they are highly selective and sensitive to NH 3 , acetone, and H 2 S with short response and recovery times. The Ag/AgCl/W 18 O 49 NRs photocatlysts also possess higher photocatalytic performance than bare W 18 O 49 NRs for degradation of methyl orange under simulated sunlight irradiation. Possible mechanisms concerning the enhancement of gas-sensing and photocatalytic activities of the Ag/AgCl/W 18 O 49 NRs composite were proposed.

Molecular insight into Al2O3 catalysts for blast furnace gas purification: K coordination and hierarchical pore enhanced COS hydrolysis

Yuting Lin,Yuran Li,Shining Wang,Jianshan Wang,Yanbin Cui,Tingyu Zhu

Blast furnace gas as a vital secondary energy in iron and steel industry, necessitates efficient removal of carbonyl sulfide (COS) to realize clean high-value utilization. However, conventional Al 2 O 3 catalysts suffer from low hydrolytic activity and poor sulfur resistance, limiting their industrial application. This work systematically elucidates the mechanisms of K coordination and hierarchical pore on COS hydrolysis. EXAFS and DFT reveal that appropriate K doping induces highly dispersed K species with four-coordinated K species featuring K-O-Al bonds, which increase the electron cloud density of O atom in surface hydroxyl groups (-OH) and significantly enhance the COS conversion by over 50%. For hierarchical pore catalysts, the introduction of expanding agent breaks the dense stacking of alumina particles, exposes more Al atoms and increases [AlO 6 ] coordination content, which synergistically enriches active -OH sites. More importantly, the interconnected hierarchical porous channels accelerate gaseous H 2 S desorption and effectively mitigate surface sulfur deposition, enabling the catalysts to maintain over 90% COS conversion for 8 h. This work provides atomic-level insights into K coordination and hierarchical pore, offering a rational strategy for designing high-efficiency and sulfur-resistant COS hydrolysis catalysts for blast furnace gas purification.

In situ construction of 1D/2D ZnO/graphdiyne oxide heterostructures for enhanced photocatalytic reduction in a gas phase

Jiangting Zhao,Zhuo Xiong,Junyi Wang,Yaqin Qiu,Yongchun Zhao,Pengfei Liu,Junying Zhang

In this study, a 1D/2D ZnO nanofiber/graphdiyne oxide heterojunction was designed for photocatalytic CO2 reduction, and the difference between graphdiyne and graphdiyne oxide was investigated as co-catalysts. The ZGDO heterostructure has strong reactant adsorption capacity due to the enlarged specific surface area and abundant hydrophilic oxygen-containing functional groups. DFT calculations, EPR, and in situ XPS further verified the S-scheme charge transfer mechanism in ZGDO. In contrast, the abilities of GD to adsorb CO2 and enhance light absorption are not as good as those of GDO, and the band structure of GD is not conducive to the formation of a favorable electric field drive at the interface with ZnO. The CO yield of ZGDO with only 3% GDO was up to 34.9 μmol h−1 g−1 in the gas–phase photocatalytic reduction of CO2, which was 4.4, 24, and 1.5 times that of ZnO, GDO, and ZnO/GD, respectively. This work opens new possibilities for the application of new non-metallic photocatalysts in the photoreduction of CO2.

A Novel Strategy to Directly Quantify Polyethylene Microplastics in PM2.5 Based on Pyrolysis-Gas Chromatography–Tandem Mass Spectrometry

Peiru Luo,Mengke Bai,Qingyun He,Zifang Peng,Lingyun Wang,Chuan Dong,Zenghua Qi,Wenfen Zhang,Yanhao Zhang,Zongwei Cai

The broad application of plastic products has resulted in a considerable release of microplastics (MPs) into the ecosystem. While MPs in other environmental matrices (e.g., soil and water) have been studied for a long time, the atmospheric fine particulate matter (PM2.5)-bound MPs are rarely investigated due to the lack of an appropriate analytical approach. The prevalently used visual and spectroscopic means (e.g., optical microscopy, Fourier-transform infrared spectroscopy, and Raman spectroscopy) suffer from obvious drawbacks that cannot precisely detect MPs of tiny sizes and provide quantitative information. In the present study, a novel strategy that does not require sample pretreatment was developed to first effectuate accurate quantification of polyethylene MP (PE-MP) in PM2.5 based on pyrolysis-gas chromatography–tandem mass spectrometry (Pyr-GC-MS/MS). It featured acceptable recoveries (97%–110%), high sensitivity (LOD = 1 pg), and qualified precisions (RSD of 3%–13%). Employing this approach, for the first time, exact atmospheric concentrations of PE-MPs in PM2.5 from megacities in North (Zhengzhou and Taiyuan) and South (Guangzhou) China were obtained, and relatively serious pollution was found in Taiyuan. The 100% sample detection rates also suggested the widespread occurrence and possible human exposure risks of PM2.5-bound PE-MPs. In brief, the new strategy could conduct direct, sensitive, and accurate quantification of PE-MP in PM2.5, favoring further studies of environmental fates, distributions, and toxicities of atmospheric MPs.

Preparation and gas separation performance of seeding-free aqueous synthesis ZIF-8 membrane by homologous-like ligands method

Tao Yan,Jianhua Yang,Jinming Lu,Liang Zhou,Yan Zhang,Gaohong He

Due to the poor heterogeneous nucleation properties of MOFs crystal on ceramic substrates resulting from the absence of interaction of MOFs with support substrate surface, it is usually difficult to prepare well-intergrown MOF membranes on substrate by simple in situ growth. In this work, a novel synthesis strategy was used to prepare defect-free ZIF-8 membranes on α-Al 2 O 3 supports by depositing gold particles modified with 2-mercaptoimidazole which creates pseudo-surfaces to bridge the metal centers with support. The end groups of the 2-mercaptoimidazole guides the heterogeneous nuclei to the support surface as homologous-like ligands. Furthermore, investigation of the metal sources revealed that the ZIF-8 membranes prepared with Zn(OAc) 2 as the zinc source possessed more continuous and well-intergrown ZIF-8 membranes with a thickness of about 1 μm compared to other zinc sources. The results of gas separation performance show that the optimized ZIF-8 membranes possess high hydrogen permeance and thermal stability. The gas separation selectivity for binary H 2 /CH 4 mixture reached 20.8 at 150 °C and 1 bar, with a high H 2 permeance of about 6.15 × 10 −7  mol m −2  s −1 Pa −1 , which is promising for hydrogen separation and purification. Moreover, free-organic solvents and room temperature growth by our strategy dramatically reduces the difficulty of preparation and environmental destruction, thus offering a new avenue to prepare MOFs membrane with good separation performance.

High-performance trimethylamine gas sensors based on defect-engineering MOF-derived ZnO nanoclusters with tunable surface oxygen vacancies

Shaoyuan Yu,Jingshi Dong,He Wang,Sirui Li,Hang Zhu,Tianye Yang

In this study, we have successfully fabricated high-performance trimethylamine (TMA) sensors. Defect-engineering (DE) strategy in which two organic ligands, i.e., dicarboxylate and tricarboxylate coordinated with Zn2+ ions, simultaneously, was adopted to obtain MOF-derived ZnO nanoclusters with tunable surface oxygen vacancies after the annealing process. The coordinate competition is expected to introduce more coordinate unsaturated metal sites (CUSs) in MOF materials and thus introduce more oxygen vacancies in MOF-derived materials. Results of gas sensing tests indicate that the dual ligand sensor (DL4) exhibits optimal TMA sensing performance including a high response value of 270.1, excellent selectivity, and good stability to 20 ppm TMA at a low operating temperature of 140 °C. Results of comprehensive characterization experiments including XPS, UV-vis spectra, PL spectra, and EPR indicate that the extraordinary TMA-sensing performance of the sensor can be attributed to abundant doubly positive oxygen vacancies on the ZnO nanocluster surface. The first-principles calculations including the TMA adsorption energy of the ZnO surface and the corresponding differential charge density were calculated using the software VASP (Vienna Ab initio Simulation Package), which further proved that the surface oxygen vacancy is beneficial to TMA sensing performance improvement. Furthermore, the TMA sensing mechanism is also discussed. The DE MOF-derived preparation strategy is a facile and effective method for designing high-performance metal oxide semiconductor gas sensing materials with tunable surface oxygen vacancies.

Adsorptive purification of NOx by HZSM-5 zeolites: Effects of Si/Al ratio, temperature, humidity, and gas composition

Yingshu Liu,Haiyang Tao,Xiong Yang,Xiaoyong Wu,Jinjuan Li,Chuanzhao Zhang,Ralph T. Yang,Ziyi Li

Adsorption is a promising technology for capturing nitrogen oxides (NO x ) from humid flue gases , for which as the preferred NO x adsorbent, zeolite with an appropriate silica to alumina (Si/Al) ratio provides the key step for success in practical applications. In this work, the effects of Si/Al ratio, temperature, relative humidity (RH), and feed gas (NO x -H 2 O(g)–CO 2 –O 2 -N 2 ) compositions on NO x sorption behavior on HZSM-5 zeolites were systematically investigated, based on a series of characterizations, fixed-bed adsorption and temperature programmed desorption (TPD) tests. The low-silica HZSM-5(25) showed the best performance (326.6 μmol/g and 39.2 μmol/g at dry and 90%RH) as compared to others with higher Si/Al ratios at each RH, in which the roll-up effect was positively correlated with the Si/Al ratios and humidity. O 2 enhanced NO x adsorption and reached an optimal adsorption capacity at the concentration of 14%, while CO 2 had little effect on NO x adsorption. The decrease in temperature increased NO x adsorption capacity on HZSM-5(25), benefitting from NO 2 physisorption as well as satisfactory NO oxidation within the active adsorbent structure. The facile thermal desorption of NO x and significant NO–NO 2 conversion on HZSM-5(25) was exhibited by bimodal TPD peaks at 343–353K and 533–543K respective for NO and NO 2 , in contrast to those on Silicalite-1. A potential “water-resistant” strategy via the enhancement of NO x adsorption competitiveness was revealed, providing a theoretical guideline for NO x adsorbent screening in industrial applications.

A powerless, gas-permeable, flexible and transparent carbon micromesh electrode for simultaneous ascorbic acid detection and pH monitoring

X. Liu,J. Song,B. Yin,T. Jiang,H. Pang,L. Yang,S. Wu

Ascorbic acid (AA) is a critical nutrition and chemical for humans, due to its crucial role in metabolic processes and medical treatments. It is necessary to develop a simple and rapid method for real-time tracking AA level in the body. In this work, we fabricated a powerless, gas-permeable, flexible and transparent AA biosensor based on carbon micromesh electrode (CME). The AA biosensor worked without an external power supply and exhibited excellent performances, including high transmittance (>95%), wide detection range (1 μM–1 mM), low limit of detection (10 nM), good selectivity and long-term storage stability (30 days). In addition, we integrated a pH-sensing electrode to correct the AA analysis. A layer of polyaniline (PANI) film was electrodeposited on the carbon micromesh as pH-sensing electrode that had an average sensitivity of 58.1 mV/pH with a high correlation coefficient ( R 2  = 0.997) within the physiological range of human body fluids (pH 4.0–8.7). To verify the availability of the CME in practical application, the Ag/C electrode was used as reference electrode to fabricate the integrated dual-functional biosensors for artificial tears detection. The CME-based biosensors showed good sensitivity, selectivity and correlation coefficient, indicating its excellent practicability towards wearable electronics.