Advanced Composites and Hybrid Materials
·
2019
·Vol. 3
·期 1
·98-113
·
IF 0
Xu Guojie,Chen Xun,Zhu Ziming,Wu Peixuan,Wang Han,Chen Xindu,Gao Wei,Liu Zhen
Multi-needle electrospinning is an effective method to increase the productivity of nanofibers. In this paper, the number of single-needle jets was increased to further improve the production efficiency. As the traditional method for increasing the number of single-needle jets has poor controllability and persistence, we proposed a gas-assisted method to increase the yield of nanofibers. A coaxial gas auxiliary needle was designed with an intermediate shaft supplied gas and the outer shaft supplied solution. Innovatively using pulse gas to produce continuous and stable bubbles which are ruptured on the needle. The liquid film is continuously disturbed, which generates jets in the electric field, thereby increasing the number of jets of a single needle. After optimization of the single-needle gas-assisted electrospinning process, the stable spraying process of 16-pin multi-needle electrospinning has been realized. The gas-assisted electrospinning productivity was 4.7 times higher than that of without gas assistance. It provided a new idea for improving the stable production of the multi-needle electrospinning.
Graphical abstract
研究领域:
生物医学工程
·
材料科学
·
纳米技术
·
高分子化学
✓ 已验证
DOI
Materials
·
2024
·Vol. 17
·期 10
·2190
·
IF 3.1
Xuemin Luo,Yanhui Jiao,Hang Li,Qi Liu,Jinfeng Liu,Mingwei Wang,Yong Liu
Transition metal dichalcogenides (TMDs), particularly monolayer TMDs with direct bandgap properties, are key to advancing optoelectronic device technology. WSe2stands out due to its adjustable carrier transport, making it a prime candidate for optoelectronic applications. This study explores monolayer WSe2synthesis via H2-assisted CVD, focusing on how carrier gas flow rate affects WSe2quality. A comprehensive characterization of monolayer WSe2was conducted using OM (optical microscope), Raman spectroscopy, PL spectroscopy, AFM, SEM, XPS, HRTEM, and XRD. It was found that H2incorporation and flow rate critically influence WSe2’s growth and structural integrity, with low flow rates favoring precursor concentration for product formation and high rates causing disintegration of existing structures. This research accentuates the significance of fine-tuning the carrier gas flow rate for optimizing monolayer WSe2synthesis, offering insights for fabricating monolayer TMDs like WS2, MoSe2, and MoS2, and facilitating their broader integration into optoelectronic devices.
研究领域:
材料科学
·
化学工程
·
光学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CELLULOSE
·
2018
·Vol. 25
·期 10
·5511-5522
·
IF 3.809
Li Xingkang,Luo Yifan,Daroch Maurycy,Hou Juan,Gui Weiyang
Hemicellulose and lignin act as physical barriers impeding the hydrolysis of lignocellulosic biomass by cellulases. To develop a process which could simultaneously remove most hemicellulose and lignin in biomass, in this study, oxygen-assisted ethanol organosolv pretreatment (O 2 -EOP) of sugarcane bagasse (SCB) was carried out. The effects of temperature, time, oxygen pressure and ethanol concentration on the pH of the hydrolysate, the solubilization and the chemical composition of SCB were investigated. Compared with autocatalytic EOP and acid-catalyzed EOP, O 2 -EOP could remove most xylan and lignin from SCB at much milder conditions. At optimized conditions (40/60 ethanol/water (v/v), 1.5 MPa O 2 , 160 °C and 80 min), 82.9% xylan and 83.3% lignin were removed. Glucan content in the residue reached 86.3%, much higher than results obtained by autocatalytic EOP and acid-catalyzed EOP. In subsequent enzymatic hydrolysis (1% solid loading, 4.96 mg protein/g cellulose, 72 h), O 2 -EOP pretreated SCB produced 3.97 and 1.90 times more glucose than untreated material and N 2 -EOP pretreated SCB, respectively. O 2 -EOP also produced abundant organic acids, total amounts of formic acid and acetic acid in the hemicellulose hydrolysate reached 5.42 g/L. In conclusion, O 2 -assisted EOP was an effective process for the production of pulp with high cellulose purity and good accessibility to cellulases.
研究领域:
生物化学
·
生物质能
·
可再生能源
✓ 已验证
DOI
高影响因子
ACS Materials Au
·
2025
·
IF 6.5
Man Liu,Weiwei Shi,Huili Liu,Yanzhen Guo,Baocheng Yang,Binbin Chang
Carbon capture has emerged as a pivotal carbon neutrality technology for addressing greenhouse effect challenges. Porous carbons are one of the most promising adsorbents for CO2 capture and separation from flue gas, yet their traditional synthesis necessitates inert atmospheres to avoid oxidation, which greatly restricts the large-scale production at a low cost and advanced industrial applications. Herein, we propose an innovative pathway for large-scale fabrication of porous carbons via one-step pyrolysis in an air environment. Porosity and surface chemistry can be concurrently tailored by controlling the air-assisted pyrolysis process, and the optimization mechanism is unveiled in detail. The resultant materials feature well-interconnected hierarchical porosity with highly proportioned ultramicroporosity, uniform spherical morphology, and high surface heteroatom doping levels. By leveraging porosity and surface chemistry, the optimal sample exhibits superior CO2 capture behaviors of satisfactory CO2 uptake and ultrahigh selectivity. CO2/N2 selectivity reaches up to 160 at 0.15 bar and 25 °C, and it still achieves up to 76 at 1.0 bar and 25 °C, ranking it in the top 5% of the reported porous carbons. We explore the correlations between porosity, surface heteroatoms, and CO2 capture behaviors. Porosity has a decisive function on CO2 capture capacity and selectivity, especially ultramicroporosity, and surface heteroatoms doping could have a positive promotion in selectivity caused by extra CO2-philic sites. This work pioneers a feasible approach for large-scale directional design of functional porous carbons through air-assisted pyrolysis under mild conditions.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
EUROPEAN FOOD RESEARCH AND TECHNOLOGY
·
2021
·Vol. 247
·期 11
·2777-2785
·
IF 2.998
Yang Yi,Yin Shuo,Wu Ling,Li Yongxin,Sun Chengjun
A novel ionic liquid-based air-assisted dispersive liquid–liquid microextraction combined with high-performance liquid chromatographic method was developed for the simultaneous analysis of oxytetracycline, tetracycline, demeclocycline, metacycline, chlortetracycline and doxycycline in honey. Tetracyclines in samples were extracted with ethyl acetate-[Bmim]PF 6 under acidic condition with the assistance of air. The analytes were separated on a C 18 column thermostated at 20 °C under gradient condition with a mobile phase consisted of methanol and oxalic acid. Parameters for the extraction (pH, dilution buffer, ionic strength, volumes of ionic liquid and ethyl acetate, assistance techniques and extraction time) were evaluated. The developed method showed good linearities over the range of 10.0–500 μg/L ( R 2 > 0.999). The enrichment factors were 16.6–41.2. The detection limits and quantification limits were 0.434–0.919 μg/kg and 1.45–3.06 μg/kg, respectively. The recoveries were 89.5–116%. The intra-day and inter-day RSDs were 0.644–6.44% and 2.35–15.9%, respectively. The developed method is sensitive, accurate, rapid, convenient, and is applicable for the determination of six tetracyclines in honey.
研究领域:
分析化学
·
食品科学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Zhoufei Luo,Jing Lu,Haipu Li,Yi Tu,Yuehao Wan,Zhaoguang Yang
A new, sensitive, and rapid method based on the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) approach and air-assisted liquid-liquid microextraction (AALLME) technology was developed for the determination of 20 endocrine-disrupting compounds (EDCs) in fish by high-performance liquid chromatography–tandem mass spectrometry. The method first integrates AALLME into QuEChERS to achieve clean-up and enrichment of the EDCs in one step. A self-made glass tube was enfolded with plasticine to withstand the high centrifugal force. The established method was developed by optimization of the parameters. High linearities (R 2 > 0.9924) and recoveries (78.2–118.6%) at three spiked levels (5, 10, and 20 ng g −1 ), and low relative standard deviation values (1.1–14.5%) and limits of detection (0.03–0.80 ng g −1 ) were obtained. The method comparison shows that the proposed method is superior as it involves less organic solvent usage, simple operation and high efficiency. This method was successfully applied to different fishes for analyzing EDCs.
研究领域:
分析化学
·
环境科学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF ANALYTICAL CHEMISTRY
·
2018
·
IF 0.824
Jing LU,Meng-Meng WANG,Qiang WANG,Hai-Pu LI,Zhao-Guang YANG
Benzotriazole and its derivatives are persistent contaminants and ubiquitous in aquatic environments. Here, a simple, reliable method based on air-assisted liquid-liquid microextraction coupled with high-performance liquid chromatography with a UV detector for determining 1H-benzotriazole, 5-methyl-1H-benzotriazole and 5-chloro-1H-benzotriazole in aqueous samples was developed. In this procedure, the analytes quickly entered into the extraction solvent via the bolus flow formed during the movement of the plunger without disperser solvent. 1-Hexanol was used as the extractant, thus avoiding chlorinated solvents, and a narrow-neck tube with round bottom was self-made to facilitate collection of the low-density extract phase and centrifugation at high speed. Those main parameters, including sample volume, type and volume of extraction solvent, number of suction-injection cycle, salt addition, and the pH were optimized. Under the optimized conditions, the pretreatment could be completed within two minutes with a good linearity ( r > 0.9996). Satisfactory intra-day (3.0%–4.3%, n = 5) and inter-day (5.9%–7.8%, n = 5) precisions were observed. Further, the method was applied in analysis of real samples including tap water, lake water, river water, and municipal waste water with good recoveries (73%−116%).
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2019
·
IF 5.439
Shaokai Zhang,Xun Ke,Tong Zeng,Yonghao Ni,Xiaolin Luo,Hui-Chao Hu,Lihui Chen,Liulian Huang
An ammonia-assisted headspace gas chromatography (HS-GC) method was developed to determine the N-methyl morpholine (NMM) concentration in biomass fractionation processes. The use of ammonia gas increased the detection sensitivity of NMM, and minimized the interfering effect of other substances during the analysis. Results showed that, by adding 1.5 mL ammonium hydroxide (28–30%, w/w) and a 0.125 mmol of sodium hydroxide into a 4.0 g of sample solution containing 43.3% N-methylmorpholine N-oxide (NMMO), the gas-liquid equilibration of NMM was obtained within 30 min at 80 °C. The optimum sample size and the NMMO content in the sample solutions were 6.0 g and 43.3%, respectively. The present method was proved to be of high precision (RSD = 4.33%), sensitivity (LOQ = 71.9 mg/kg), and with recovery accuracy of 96.0–102%. The present method was rapid, accurate, which will be a powerful tool to optimize the reaction conditions in NMMO-based biomass pretreatment process for enhancing the cost effectivity.
研究领域:
分析化学
·
生物质能
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2014
·
IF 4.835
Sujie Chang,Shigang Ruan,Erlong Wu,Weixin Huang
Oxide-on-metal particles with exposed interfaces exhibit wealthy structures and functions, but their facile synthesis remains as a challenge. Herein we report a facile O2-assisted hydrothermal method to synthesize CeO2-on-Ag particles with different CeO2 thicknesses. In this novel approach Ag particles catalyze the O2 + H2O reaction to form surface hydroxyls that induce the preferential nucleation of Ce(OH)3 on the surfaces of Ag particles, eventually forming CeO2 adlayers on Ag particles. CeO2-on-Ag particles exhibit the CeO2 thickness-dependent SERS effect in which their best SERS effect is 2 orders stronger than that of Ag particles. They also exhibit CeO2 thickness-dependent catalytic performance in CO oxidation in which the best one is as active as traditional CeO2-supported Ag catalyst. These results open up new opportunities to synthesize oxide-on-metal particles and explore their functions by tuning the oxide adlayer thickness.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2022
·Vol. 189
·期 2
·1-12
·
IF 6.408
Li Guofu,Xie Guoqiang,Gong Chong,Chen Di,Chen Xing,Zhang Qian,Dong Hongzhou,Zhang Yingchao,Li Chengjie,Hu Jing,Chen Yingjie,Yu Liyan,Dong Lifeng
Chains of nickel nanoparticles coated with few nitrogen-doped graphitic carbon layers (Ni@NC) are synthesized by hydrogen-assisted pyrolysis of Ni-ZIF. Hydrogen and temperature can play key roles in the formation of oriented Ni@NC nanoparticle chains, and carbon shells can protect Ni nanoparticles from external oxidation and aggregations. Under the optimized potential (0.60 V vs. Ag/AgCl), the Ni@NC7H nanoparticle chains obtained at 700 °C under H 2 /Ar atmosphere (Ni@NC7H) demonstrate outstanding performances, such as high sensitivity of 1.44 mA mM −1 cm −2 (RSD = 1.0%), low detection limit of 0.34 μM (S/N = 3), broad linear range from 1 μM to 1.81 mM, and excellent application potential in artificial sweat and human serum. Therefore, the findings above indicate that this study will provide a general methodology for the synthesis of chains-like core–shell nanoparticle electrocatalysts for non-enzymatic glucose detection. Graphical abstract
研究领域:
材料科学
·
电化学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2021
·
IF 7.514
Kaige Zhang,Yunhe Wang,Shuangying Li,Guifen Zhu
Deep eutectic solvents (DESs) are a new class of green “designer solvent”; its physicochemical properties can be easily tuned by adjusting DES′ constituents, chemical ratio and water content. In this study, three hydrophobic DESs with low viscosity, low density, and melting points close to room temperature were designed and synthesized. Based on these DESs , an air-assisted liquid–liquid microextraction technique was developed based on the solidification of floating DESs for the simultaneous determination of bisphenols and polycyclic aromatic hydrocarbons (PAHs) via HPLC. The microextraction parameters were optimized via the Plackett-Burman design and response surface methodologies. The method shows satisfactory linearity (R 2 ≥ 0.9928), a low limit of detection (0.16–0.75 μg L −1 ) and satisfactory precision (≤2.3%), and was successfully applied for the simultaneous determination of bisphenols and PAHs from tea infusions with satisfactory recoveries (82.0–116.6%). This method is simple, rapid, economical, environmentally compatible, dispersive solvent-frees and centrifugation-free, and has promising applications in food safety.
研究领域:
分析化学
·
食品安全
·
环境科学
✓ 已验证
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2022
·
IF 5.304
Kaige Zhang,Rong Guo,Yunhe Wang,Jing Wang,Qiujun Nie,Bin Li,Guifen Zhu
A novel and green microextraction technique, temperature-controlled air-assisted liquid–liquid microextraction based on the solidification of floating deep eutectic solvents (DESs), was developed and applied for the extraction of triclosan and alkylphenols in different environmental waters. Hydrophobic DESs composed of menthol and myristic acid with melting points slightly higher than room temperature (25 ± 2 °C) were prepared and used as extraction solvent . First, the solid DES was transformed into liquid DES while the aqueous sample was heated in a water bath. Then, fine droplets were formed by withdrawing and injecting the mixture of aqueous sample and DES with a 1 mL pipette several times. After extraction, the solidified DES phase was obtained in an ice water bath. And then the analyses were performed by HPLC-UV. The microextraction parameters were investigated by the Plackett-Burman design and central composite design. The analytical parameters of this method were investigated and good linear ranges (0.5/1.0–400 μg/L, R 2 ≥ 0.9950), limits of detection (0.1–0.5 μg/L) and precision (≤5.9 %) were obtained. This method was successfully applied for the determination of triclosan and alkylphenols from five water samples with satisfactory recoveries (80.0–104.3 %). Subsequently, the green profile of the method was assessed by analytical Eco-Scale and Complementary Green Analytical Procedure Index. This method has the advantages of simplicity, rapidity, low cost, high sensitivity and green, which expands the application of solid solvents in liquid–liquid microextraction and has a wide application prospect.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）