Separation Science Plus
·
2019
·Vol. 2
·期 10
·384-391
·
IF 0
Zhongping Huang,Xiaoli Huang,Huijun Liu,Lili Wang,Yilei Fan,Charles Liu,Yiping Ren
A new method of direct analysis in real-time integrated with mass spectrometry was established and applied to the rapid determination of ferulic acid in Chinese herbs. Instrument parameter settings were optimized to obtain the sensitive and accurate determination of ferulic acid. At the sample introduction speed of 0.5 mm/s, high signal intensity of [M-H] − ( m/z 193) for ferulic acid was achieved in the negative ion mode by utilization of high purity helium gas at 350°C. The calibration curve was linear over the range of 5 – 100 mg/L with the correlation coefficient r = 0.9846 and relative standard deviation (n = 6) in the range of 2.0 to 6.1%. The limit of detection ( S/N = 3) and limit of quantitation ( S/N = 10) were 0.4 and 1.2 mg/L respectively. The recoveries were in the range of 90.6–114.2%. The results of direct analysis in real time-mass spectrometry were in agreement with those obtained by high performance liquid chromatography. The proposed direct analysis in real time mass spectrometry method is a simple, rapid and high-throughput approach for the determination of ferulic acid in Chinese herbs.
研究领域:
中药学
·
分析化学
✓ 已验证
DOI
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2024
·
IF 1.5
Gao Kai,Shi Yunfeng,An Kexin,Tan Jun,Zhang Yanna,Dong Jiajie,Yu Weiyue,Lin Haipeng
A hydrothermal method which can convert free cesium ions into stable pollucite at low temperatures was established in this work, avoiding any evaporation pollution during the disposal of cesium containing waste. Meanwhile, rapid synthesis under hydrothermal conditions was achieved using seed guidance, which shorten the growth time of pollucite crystals to 8 h, and making the treatment and disposal of cesium containing wastewater faster. Standard leaching test results show that the leaching rate of Cs was very low (< 3.5 × 10 −7 g·m 2 ·d), it still has good thermal stability at a temperature of 1300 °C, when the cesium content in pollucite reaches 20%.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Optical Materials
·
2024
·Vol. 12
·期 22
·2400648
·
IF 8
Shiwei Zhang,Jiurong Li,Xiao Gong
Carbon nanodots (CDs) possess exceptional fluorescence properties, which have been extensively studied in the fields of fluorescence detection and anti-counterfeiting information. However, the exploration of CDs with simple and fast synthesis paths, secure, and efficient encryption properties, remains a challenge. The rapid synthesis of orange CDs (O-CDs) is reported with a high photoluminescence quantum yield (PLQY) of 57.6% within 10 min at atmospheric pressure using a one-step pyrolysis method. The O-CDs exhibit a dual-emission property, with a blue emission peak at 425 nm and a strong orange emission peak at 590 nm. The dual-emission peaks of O-CDs can allow for fast orange/blue switching of fluorescence color with changes in the acid-base environment. O-CDs can serve as effective fluorescent probes for pH detection, depending on their fluorescence wavelength and intensity. Additionally, O-CDs have potential for fluorescence anti-counterfeiting. When exposed to NH 3 gas, O-CDs fluorescent ink rapidly (1 s) transitions from orange fluorescence to blue fluorescence, and then quickly (4 s) reverts back to orange fluorescence when the gas environment changes to HCl gas atmosphere. Thus, O-CDs fluorescent inks offer several advantages, including high fluorescence intensity, fast response, recyclability, and lossless encryption/decryption in “on-off-on” double encryption anti-counterfeiting.
研究领域:
材料科学
·
化学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2016
·
IF 4.12
Erwei Leng,Yang Wang,Xun Gong,Biao Zhang,Yang Zhang,Minghou Xu
The influence of KCl and CaCl 2 on the primary reactions of cellulose pyrolysis is studied using a wire-mesh reactor from 250 °C to 600 °C, focusing on the reaction intermediates. A pre- column derivatization with benzoyl chloride prior to HPLC analysis is applied for the quantification of anhydro-sugars (levoglucosan, cellobiosan, maltosan) from pyrolysis. At low temperatures, the additions of inorganics salts, especially CaCl 2 , weakens hydrogen bonds, resulting in high yields of levoglucosan and cellobiosan from the cleavage of glycosidic bonds rather than from dehydration reactions . At elevated temperatures, dehydration reactions in the sugar units are mainly responsible for the destruction of sugar rings followed by the scission of pyran rings, leading to the weight-loss of CaCl 2 -loaded cellulose in the form of low molecular weight organic species. Meanwhile, accumulated unsaturated structures suppress the cleavage of glycosidic bonds, leading to the formation of char. However, KCl appears to catalyze the cleavage of glycosidic bonds or the scission of pyran rings directly, which perhaps occurs through a homolytic mechanism, leading to low molecular weight species. Furthermore, maltosan is shown to be a secondary product and is catalyzed by KCl and CaCl 2 indirectly through the repolymerization of levoglucosan in the solid phase. A modified mechanism is also proposed regarding cellulose pyrolysis and the primary catalysis of KCl and CaCl 2 .
研究领域:
化学工程
·
能源科学
✓ 已验证
DOI
高影响因子
Foods
·
2022
·Vol. 11
·期 17
·2650
·
IF 5.561
Hongfang Li,Jie Chen,Baowei Huang,Lingwei Kong,Feifei Sun,Lin Li,Chuanyi Peng,Huimei Cai,Ruyan Hou
Rongalite was reported illegally used as a food additive for bleaching purposes and improving the tenderness of foodstuffs, which may endanger public health. At present, rongalite was mostly detected by indirect methods via derivatization or determining its decomposition products. In this study, we developed a new fluorescence sensor for the direct quantification of rongalite based on the principles: (1) dopamine reacts with resorcinol and generates strong fluorophore (azamonardine); (2) rongalite could inhibit the production of fluorophores and then result in lower fluorescence intensity. Hence, the rongalite concentration was inversely proportional to fluorescence intensity of fluorophore. Several crucial reaction conditions of fluorescence sensor were further optimized, such as dopamine and resorcinol concentration, pH values, and reaction time. Under the optimal conditions, the limit of detection of fluorescence sensor was 0.28–0.38 μg/g in vermicelli, wheat and rice powder samples, exhibiting almost 3.5-fold improvement compared to that of lateral flow immunoassay. Moreover, the detection time was substantially decreased to 20 min. The recoveries in spiked samples were 80.7–102.1% with a coefficient of variation of less than 12.6%. In summary, we developed a direct, high throughput, selective and accurate fluorescence sensor that poses a promising application for the rapid detection of rongalite in foodstuffs.Keywords:rongalite;fluorescence sensor;rapid detection;foodstuffs
研究领域:
食品科学
·
分析化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2018
·
IF 4.513
Xiufang He,Zhansheng Wu,Zhonghai Sun,Xinhui Wei,Zhilin Wu,Xinyu Ge,Giancarlo Cravotto
A novel hybrid material was prepared by grafting β-cyclodextrin (β-CD) onto the surface of oxidized AC for the rapid adsorption of naphthalene . AC and CDACs were characterized using the N 2 adsorption–desorption method, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and solid state CP MAS 13 C NMR. All the results demonstrate that β-CD grafted successfully onto AC. Batch experimental adsorption datas had a higher correlation to Freundlich isotherm model and the pseudo-second-order model. The adsorption equilibrium capacity of 178.73 mg·g −1 was reached in just 10 s at an AC/β-CD grafting ratio value of 1:1. It had a faster adsorption rate than many reported adsorbents. Additionally, the positive free energy change (∆G°), and the positive enthalpy change (∆H°) suggest that it is a viable, spontaneous and endothermic process, which will provided a new path to a highly-efficient and fast-adsorption-rate adsorbent for naphthalene or its analogues discharged into the environment.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
COMBUSTION AND FLAME
·
2019
·
IF 4.12
Bin Hu,Qiang Lu,Zhen-Xi Zhang,Yu-Ting Wu,Kai Li,Chang-Qing Dong,Yong-Ping Yang
The fast pyrolysis mechanism of xylose , xylobiose and xylan was investigated with combined fast pyrolysis experiments and quantum chemistry calculations. The results indicate that acyclic d -xylose is an important intermediate for the formation of the major pyrolytic products in xylose pyrolysis, i.e., 1,4-anhydro- d -xylopyranose (ADX), furfural (FF) and hydroxyacetaldehyde (HAA). ADX derives from the successive cyclization of d -xylose which is the only source for ADX formation. 3-Deoxy-xylose is the most important intermediate for FF formation. HAA results from the C C bond scission by retro-aldol and cyclic Grob fragment. In addition, the five-membered intermediate derived from the ring-contraction reaction can transform into FF with high selectivity. The dehydrated xylose is also another source for HAA formation. The fast pyrolysis mechanism of xylobiose is similar to that of xylose, and thus similar pyrolytic product distribution can be obtained from them. However, the pyrolytic products of xylan differ significantly from those of xylose and xylobiose, which is ascribed to its high degree of polymerization and the branches in it.
研究领域:
化学工程
·
生物质能
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF ANALYTICAL CHEMISTRY
·
2016
·
IF 0.566
Da-Peng GUO,Yong-Huan WANG,Tian-Bai XU,Yuan ZHANG,Ling-Feng Li,Jin-Kai CHEN,Xiao-Zhi WANG,Peng LI,Ji-Kui LUO
The microchip field asymmetric ion mobility spectrometry (FAIMS) technology was used for rapid analysis of phenylalanine (PHE) using the metal diffusion tube-microchip μ-FAIMS system. The test pressure was set at 0.25 MPa, and the temperature of the gas generator for the diffusion tube was at 190 °C. The ion characteristic spectra were acquired under the optimized conditions with a gas flow rate of 2000 mL min −1 , a dispersion voltage of 152.8 V and a compensation voltage of −0.62 V for phenylalanine in positive mode. Phenylalanine gas samples with different concentrations were analyzed in detail by FAIMS. The results showed that the ion intensity was linearly correlated with phenylalanine concentration in the range from 6 mg L −1 to 20 mg L −1 , with the detection limit of 5.93 mg L −1 for phenylalanine. This investigation shows the feasibility of FAIMS technique for rapid detection of phenylalanine. The FAIMS instrument is simple, and has high sensitivity and fast response, and shows great potential for rapid detection of phenylalanine.
研究领域:
分析化学
·
医学检验
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2021
·
IF 5.541
Jianjun Xiao,Minjiao Yang,Qingfeng Che,Yingquan Chen,Xu Chen,Haiping Yang,Pietro Bartocci,Francesco Fantozzi,Hanping Chen
The effect of potassium in biomass on the catalytic activity of ZSM-5 zeolite in the fast pyrolysis of biomass was investigated using 2-methylfuran (2-MF) as the typical model compound. The mechanism of action of potassium was explored in detail, along with the physicochemical properties of ZSM-5, including crystallinity, pore structure, and surface acidity. The physicochemical properties of ZSM-5 deteriorated to varying degrees after being tainted with different potassium sources (KOH, K 2 CO 3 , KAc, and KCl). Compared with neutral KCl and strong alkali KOH, K 2 CO 3 , and KAc, with weaker alkalinity but larger crystal structure, exerted a larger influence on ZSM-5. Changes in ZSM-5 tainted with K 2 CO 3 were the greatest, and crystallinity, surface area, acidity, and the corresponding yields of valuable aromatic hydrocarbons and gas products, all declined significantly, compared with raw ZSM-5. When the amount of K(CO 3 2− ) on ZSM-5 was less than 0.5 wt%, only minor (<10 %) changes were observed in crystallinity and surface area, but total acidity decreased by over 30 percent. The conversion of 2-MF was increased using ZSM-5 tainted with less than 0.5 wt% K(CO 3 2- ) and less liquid oxygenated compounds and more CO 2 were produced. Appropriate total acidity, adjusted by a tiny amount of K 2 CO 3 , could promote deoxygenation to CO 2. However, the decarbonylation reaction was inhibited, causing a negative effect on monocyclic aromatic hydrocarbons, which was attributed to the large-scale loss of both acidity and physical structure of ZSM-5 caused by more than 1.0 wt% K(CO 3 2- ).
研究领域:
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2016
·
IF 3.349
Chen Liu,Lu Bai,Jianming Zhang,Deng Hu,Meng Li,Gaofeng Zeng,Yanfeng Zhang,Wei Wei,Yuhan Sun
Rapid synthesis and characterization of all-silica Deca-Dodecasil 3 Rhombohedral (DD3R) zeolite were systematically studied with (NH 4 ) 2 SiF 6 as silica source. The effects of gel recipe, synthesis temperature and time, seeding, aging and silica source were investigated systematically. Big DD3R crystals (50–150 μm) with various morphologies (hexagonal plate, polyhedron and rhombohedron) were obtained by tuning the synthesis temperature, time, seeding and aging. Compared with other silica sources, (NH 4 ) 2 SiF 6 is very reactive which enhances the nucleation and crystal growth of DD3R zeolite significantly. At 220 °C, highly crystalline DD3R was obtained in 12 h without seeding, which is the fastest synthesis up to now. Aging and seeding reduced the synthesis time substantially and led to smaller crystals. With the help of seeding and aging, pure DD3R crystals were obtained in 6 d at 100 °C, which opens the door to synthesis at low temperature and ambient pressure. Mixed silica sources can reduce the consumption of expensive (NH 4 ) 2 SiF 6 . Higher calcination temperature is required for the complete template removal of the big DD3R crystals obtained in this study, which hinders the diffusion of oxidation products from the template. Zeolites SGT and DOH are competing phases in the synthesis of DD3R. The introduction of Al into the mother liquor led to the formation of zeolite SGT.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 15
·2259
·
IF 5.3
Haixia Wu,Zhenxu Lin,Jie Song,Yi Zhang,Yanqing Guo,Wenxing Zhang,Rui Huang
Zero-dimensional (0D) tin halide perovskites feature extraordinary properties, such as broadband emission, high photoluminescence quantum yield, and self-absorption-free characteristics. The innovation of synthesis approaches for high-quality 0D tin halide perovskites has facilitated the flourishing development of perovskite-based optoelectronic devices in recent years. However, discovering an effective strategy to further enhance their emission efficiency remains a considerable challenge. Herein, we report a unique strategy employing rapid heat treatment to attain efficient self-trapped exciton (STE) emission in Cs4SnBr6zero-dimensional perovskite. Compared to the pristine Cs4SnBr6, rapid thermal treatment (RTT) at 200 °C for a duration of 120 s results in an augmented STE emission with the photoluminescence (PL) quantum yield rising from an initial 50.1% to a substantial 64.7%. Temperature-dependent PL spectra analysis, Raman spectra, and PL decay traces reveal that the PL improvement is attributed to the appropriate electron–phonon coupling as well as the increased binding energies of STEs induced by the RTT. Our findings open up a new avenue for efficient luminescent 0D tin-halide perovskites toward the development of efficient optoelectronic devices based on 0D perovskites.Keywords:photoluminescence;self-trapped exciton;Cs4SnBr6;rapid thermal treatment
研究领域:
材料科学
·
光电学
·
光子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2022
·
IF 5.304
Wenjing Wang,Fei Zhai,Fupei Xu,Min Jia
Novel enzyme-free amplified dual-terminal labeled split aptamer (SPA) probes were developed to achieve one-step rapid and sensitive detection of bisphenol A (BPA). By rational split, the original aptamer was divided into two segments named SPA-a and SPA-b to achieve target-driven self-assembly and form BPA/SPA complex. To achieve enzyme-free signal amplification and improved sensitivity, SPA probes were dual-terminal labeled with 6-carboxyfluorescein (FAM) fluorophores and black hole quencher 2 (BHQ 2 ). Two dual-terminal labeled SPA probes were induced to assemble a ternary complex with BPA to produce fluorescence resonance energy transfer effect, generating the decreased fluorescence intensity. The detection limit of dual-terminal labeled SPA probes was 0.89 ng/mL, which was 24-fold lower than that of single-terminal modification. Meanwhile, these SPA probes showed a rapid response to BPA, which could be completed in 5 min for one-step detection without complex cleaning and separation progress. The recovery rates in real samples were 94.17% to 107.28%. In brief, the dual-terminal labeled SPA probes showed substantial potential for onsite detection of BPA.
研究领域:
分析化学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）