SCIENCE OF THE TOTAL ENVIRONMENT
·
2019
·
IF 5.589
Hu Cheng,Yang Song,Yongrong Bian,Rongting Ji,Fang Wang,Chenggang Gu,Xinglun Yang,Mao Ye,Gangfeng Ouyang,Xin Jiang
There is urgent demand for the design of advanced coating materials for solid-phase microextraction (SPME) for water quality monitoring and assessment because of the global occurrence of chlorobenzenes (CBs). In this study, we proposed a dual-order activation method in which potassium hydroxide is used to modify pre-activated calcium citrate to synthesize a highly developed meso-/microporous carbon (MMC). The as-obtained MMC presented well-developed porosity with a super-high specific surface area (2638.09 m 2 g −1 ), abundant meso-/micropores (0.5–10 nm), high hydrophobicity , excellent thermal stability (>720 °C), and a partly graphitized structure. As a coating material for headspace-SPME, the MMC-coated fiber exhibited outstanding extraction capability for CBs (up to 48.5 times higher than that of commercial fibers), which may be attributed to multiple interactions between the MMC and the pollutants, including size selectivity , micropore filling, π-π stacking and hydrophobicity. Finally, a satisfactory method using an MMC-coated fiber coupled with gas chromatography and electron capture detection was developed with good linearity (1–1000 ng L −1 , R 2 > 0.9982), high enrichment efficiencies (enrichment factors, 861–7819), low limits of detection (0.003–0.072 ng L −1 ), excellent repeatability (0.7–5.3%) and reproducibility (1.7–5.1%), and outstanding recoveries (90.18–103.02%) when applied to determine trace CBs in real water samples. These results suggest that MMC is a promising coating material for the SPME of CBs.
研究领域:
环境科学
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分析化学
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2018
·
IF 3.412
Ke-Jian Li,Ren-Yu Qu,Yu-Chao Liu,Jing-Fang Yang,Ponnam Devendar,Qiong Chen,Cong-Wei Niu,Zhen Xi,Guang-Fu Yang
The issue of weed resistance to acetohydroxyacid synthase (EC 2.2.1.6, AHAS) inhibitors has become one of the largest obstacles for the application of this class of herbicides. In a continuing effort to discover novel AHAS inhibitors to overcome weed resistance, a series of pyrimidine–biphenyl hybrids (4aa–bb and 5aa–ah) were designed and synthesized via a scaffold hopping strategy. Among these derivatives, compounds 4aa (Ki = 0.09 μM) and 4bb (Ki = 0.02 μM) displayed higher inhibitory activities against Arabidopsis thaliana AHAS than those of the controls bispyribac (Ki = 0.54 μM) and flumetsulam (Ki = 0.38 μM). Remarkably, compounds 4aa, 4bb, 5ah, and 5ag exhibited excellent postemergence herbicidal activity and a broad spectrum of weed control at application rates of 37.5–150 g of active ingredient (ai)/ha. Furthermore, 4aa and 4bb showed higher herbicidal activity against AHAS inhibitor-resistant Descurainia sophia, Ammannia arenaria, and the corresponding sensitive weeds than that of bispyribac at 0.94–0.235 g ai/ha. Therefore, the pyrimidine–biphenyl motif and lead compounds 4aa and 4bb have great potential for the discovery of novel AHAS inhibitors to combat AHAS-inhibiting herbicide-resistant weeds.
研究领域:
植物学
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农学
·
分子生物学
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DOI
PubMed
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2014
·Vol. 37
·期 7
·861-867
·
IF 2.594
Meng Wang,Fa-Qiong Zhao,Bai-Zhao Zeng
A novel polycarbazole coating was prepared by cyclic voltammetry on a platinum wire. The solution for electropolymerization contained N , N -dimethylformamide, propylene carbonate (v/v = 1:9), 0.10 M carbazole and 0.10 M tetrabutylammonium perchlorate; the cyclic scan potential range was 0.8–2.0 V (versus Ag/AgCl). The resulting polycarbazole coating showed a porous structure and had a large specific surface area. When it was used for the headspace solid-phase microextraction of chlorobenzenes (i.e. chlorobenzene, 2-chlorotoluene, 1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,2,4-trichlorobenzene) followed by GC analysis, it presented excellent analytical performance. Under the optimized conditions the linear ranges were 0.25–250 μg/L with correlation coefficients >0.985, and the low detection limits were 15–61 ng/L (S/N = 3) for different chlorobenzenes. The RSDs were 2.4–4.9% for five successive measurements with a single fiber, and for fiber-to-fiber they were 6.3–13.1% ( n = 5). Furthermore, the polycarbazole coating displayed good thermal stability (>350°C) and durability (more than 250 times). The proposed method was successfully applied to the extraction and determination of chlorobenzenes in waste water and lake water, and the recoveries for standards added were 86–114% for different analytes.
研究领域:
分析化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2024
·
IF 4.1
Qian Zhang,Xiaoqin Sun,Yuan Dang,Jun-Jie Zhu,Yuanzhen Zhou
In this work, Fe 3 O 4 -anchored nitrogen-doped carbon catalyst (Fe 3 O 4 @N–C) with abundant oxygen vacancies (V o ) and mesoporous structure was successfully synthesized for electro-Fenton (EF) catalytic process. The catalyst demonstrated impressive degradation efficiency towards nitroso-containing organics due to the superior electronic transfer of N–C skeleton and V o , making it easier for the electron-deficient –NO 2 groups to adsorb on the catalyst surface and oxidize rapidly. Typically, the degradation efficiency of p-nitrophenol (PNP) reached 95.6 % in natural pH. Notably, the catalyst exhibited excellent performance over a wide pH range (3 ∼ 11), and has strong anti-interference performance against anions and natural organic matter in water matrix. Mechanism analysis indicated that V o could promote the formation of highly active electron-rich Fe(II) species, and promote the activation of H 2 O 2 and O 2 as additional active sites, thus, a large amount of ·OH and O 2 ·- would be produced and then quickly converted into 1 O 2 . As a result, 1 O 2 is the main reactive species for PNP degradation in Fe 3 O 4 @N–C electro-Fenton reaction. The results will provide insights into the design of high-performance catalysts for the selective oxidation of organic pollutants in wastewater.
研究领域:
环境科学
·
催化材料
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产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2023
·
IF 4.8
Boying Yue,Xiyue Wang,Lili Lian,Yanyan Wang,Wenxiu Gao,Hao Zhang,Jinfeng Zhao,Dawei Lou
A needle-type extraction device (NTED) packed with ionic liquid-based molecularly imprinted polymers (MIP) coated copper fiber was produced for extraction of chlorobenzenes (CBs) in the aqueous environment followed by detection with GC-FID. Precipitation polymerization was performed to synthesize CBs imprinted polymers (CBs-MIP) with CBs as a mixed template, and 1-vinyl-3-aminoformylmethyl imidazolium chloride ionic liquid ([VAFMIM]Cl) as a functional monomer. Then CBs-MIP was coated on the braided copper fiber surface by sol–gel technology, which was served as a coated fiber to extract five trace CBs in drinking water, river water and industrial wastewater. The effects of several experimental conditions on extraction, including extraction time and temperature, pump flow rate, stirring speed, desorption time and temperature were studied by the single factor and experimental design method. A Plackett-Burman design (PBD) was used to screen the significant factors and a Box-Behnken design (BBD) was applied to optimize the significant variables to obtain the optimum extraction conditions. The limits of detection (0.0073–0.0130 μg L −1 ) and enrichment factors (2158–4087) for studied CBs were obtained after optimization. Moreover, the recoveries of CBs spiked in real water samples were 80.01–97.10% with RSD less than 7.70%. The experimental results confirmed that the NTED packed with CBs-MIP coated fiber is a promising device for extracting trace CBs from the water matrix.
研究领域:
环境科学
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分析化学
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产品关联
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2025
·
IF 3.6
Jiaxuan Dong,Yifan Lv,Yiyang Li,Kexin Xu,Xinrui Cui,Cun-Yue Guo,Baolin Li
Thienoacenes are a prominent class of fused-ring conjugated organic compounds and have attracted considerable attention due to their high coplanarity, good stability, high charge-carrier mobility, etc. However, most current synthetic methods toward thienoacenes require costly starting materials and reagents, as well as a lengthy synthetic procedure with low overall yields. Herein, a nonprecious copper-catalyzed system without additional ligands was developed to facilitate C–S coupling and 5-endo-dig thienannulation reaction, leading to the synthesis of a range of thienoacenes including dithieno[3,2-b:2′,3′-d]thiophenes (DTTs) and thieno[2′,3′:4,5]thieno[3,2-b]thiophene[2,3-d]thiophene (TTAs) with yields of up to 90% (for single-sided thienannulation reactions) and 65% (for double-sided thienannulation reactions). In addition, three π-extended DTTs were studied as potential thermoelectric materials, and their composites with single-walled carbon nanotubes (SWCNTs) exhibited high thermoelectric performance with the power factor up to 399.01 ± 16.26 μW m–1 K–2 at room temperature, which is the highest reported for thermoelectric composites comprising small-molecule thiophene derivatives and SWCNTs, signifying a step forward in the development of high-performance thermoelectric composites based on thiophene derivatives.
研究领域:
有机化学
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材料科学
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热电研究
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DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2024
·
IF 9.7
Shengtao Jiang,Haoyang Liu,Weixi Zhang,Ying Lu
Microbial fuel cell (MFC) is a promising device for water decontamination and energy generation. However, the correlation between power generation and pollutant degradation has not been clarified. Herein, a ruthenium–activated carbon (Ru–AC) bioanode was constructed for chlorobenzenes (CBs) treatment. The pollutant tolerance was improved by Ru–AC anode, and the minimum removal efficiencies of CB and ortho -dichlorobenzene ( o -DCB) reached 75.1 % and 69.3 %, respectively, which were considerably higher than those of other MFCs (16.3 %–39.7 %). Correspondingly, the maximum output voltage reached 360.7 mV for the Ru–AC anode, whereas the values obtained from others reached 45.2–149.6 mV. Interaction models were introduced to quantify the relationship between power generation and pollutant degradation. The conversion of highly toxic chlorophenols to organic acids could be accelerated by boosting the mass and electron transfer, thereby simultaneously enhancing CBs removal and power generation. This work provided important insights into pollutant-powered MFC development.
研究领域:
环境科学
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生物技术
·
能源工程
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产品关联
DOI
PubMed
高影响因子
Plants-Basel
·
2021
·Vol. 11
·期 1
·13
·
IF 3.935
Yuting Wang,Hongliang Zhang,Chao Wan,Xian He,Jinfeng Huang,Meiling Lyu,Yuan Yuan,Binghua Wu
Volatile benzenoid compounds are found in diverse aromatic bouquets emitted by most moth-pollinated flowers. The night-bloomingJasminum sambacis widely cultivated worldwide in the tropics and subtropics for ornamental and industrial purposes owing to its fragrant flowers. Benzylacetate is a characteristic constituent in jasmine scent which makes up to approximately 20–30% of the total emission in the headspace or extract, but the biosynthesis enzymes and the encoding genes have not yet been described. Here, we identify two cytosolic BAHD acyltransferases specifically expressed in the petals with a positive correlation closely to the emission pattern of the volatile benzenoids. Both JsBEAT1 and JsBEAT2 could use benzylalcohol and acetate-CoA as substrates to make benzylacetate in vitro. The recombinant GST-JsBEAT1 has an estimated apparentKmof 447.3 μM for benzylalcohol and 546.0 μM for acetate-CoA, whereas in the instance of the His-JsBEAT2, theKmvalues are marginally lower, being 278.7 and 317.3 μM, respectively. However, the catalytic reactions by the GST-JsBEAT1 are more efficient than that by the His-JsBEAT2, based on the steady-statekcatparameters. Furthermore, ectopic expression of JsBEAT1 and JsBEAT2 in the transgenicP. hybridaplants, driven by a flower-specific promotor, significantly enhances the biosynthesis of benzylbenzoate and benzylacetate, as well as the total VOCs.Keywords:Jasminum sambac;Oleaceae;BAHD acyltransferases family;benzyl alcohol O-acetyltransferase (BEAT);enzyme kinetics;floral scent;benzenoid;benzyl acetate
研究领域:
植物生物化学
·
分子生物学
·
酶学
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产品关联
DOI
PubMed
高影响因子
Food Chemistry-X
·
2024
·
IF 6.5
Tiehan Li,Yuming Wei,Mingxia Lu,Yida Wu,Yanqun Jiang,Han Ke,Aiju Shao,Jingming Ning
Piling fermentation (PF) is crucial for Pu-erh tea aroma, yet its microbial and moist-heat impact on aroma quality is poorly understood. Solid-phase microextraction, solvent-assisted flavor evaporation, and gas chromatography–mass spectrometry were used to detected and analyses the samples of sun-green green tea, sterile PF and spontaneous PF. Microbiological action promotes the formation of stale aromas. Moist-heat action promotes the formation of plum-fragrance and sweet aroma. 20 microbial markers and 28 moist-heat markers were screened from 184 volatile components. Combining odor activity values and gas chromatography-olfactometry, 22 aroma-active compounds were screened (1,2,3-trimethoxybenzene, linalool, 1,2,4-trimethoxybenzene …), and analyzed during PF processing. Aroma omission and addition experiments verified its importance. Gallic acid addition experiments successfully verified that microorganisms are the main contributors to the synthesis of methoxybenzenes. Finally, Blastobotrys, Rasamsonia , and Thermomyces showed positive correlation with the synthesis of 1-ethyl-4-methoxybenzene, 1,2,4-trimethoxybenzene, 1,2,3-trimethoxybenzene, and 1,2-dimethoxybenzene. The formation mechanism of Pu-erh tea's aroma was clarified. Exploring microbial and moist-heat effects on Pu-erh tea volatiles and understanding the methoxybenzene formation mechanism using molecular sensory science.
研究领域:
食品科学
·
微生物学
·
感官科学
·
化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD SCIENCE
·
2024
·
IF 3.2
Liyang Wei,Qian Hu,Lei He,Guoping Li,Jiukai Zhang,Ying Chen
The folk proverb “the older, the better” is usually used to describe the quality of Citrus grandis “Tomentosa” (CGT) in China. In this study, CGT aged for 6-, 12-, 16-, and 19-years were collected for the investigation of infusion color, main bioactive components, antioxidant activity, metabolic composition, and pathway. The results found that infusion color, the total phenolic and flavonoid, and antioxidant activity of CGT were obviously changed by aging process. Through untargeted metabolomics, 55 critical metabolites were identified to in discrimination of CGT with different storage ages, mainly including phenylpropanoids, lipids, and organic oxygen compounds. Twenty compounds that showed good linear relationships with storage ages could be used for year prediction of CGT. Kyoto encyclopedia of genes and genomes enrichment pathway analysis uncovered important metabolic pathways related to the accumulation of naringin, kaempferol, and choline as well as the degradation of benzenoids, thus supporting that aged CGT might be more beneficial to health. Correlation analysis provided that some key metabolites with bitter taste and biological activity were involved in the darkening and reddening of CGT infusion during aging, and total phenolic and flavonoid were more strongly associated with the antioxidant activity of CGT. This study systematically revealed the quality changes and key metabolic pathways during CGT aging at first time. Practical Application This study reveals the differences in quality attributes and metabolic profile between CGT with different storage ages, providing guidance for consumers' consumption, and also providing more scientific basis for the quality evaluation and improvement of CGT.
研究领域:
食品科学
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代谢组学
·
药理学
·
植物科学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENT INTERNATIONAL
·
2022
·
IF 13.352
Yahui Liu,Zhijuan Wang,Wan Wang,Jiangtao Xing,Qing Zhang,Qiang Ma,Qing Lv
This paper reports the non-targeted analysis of unknown volatile chemicals in medical masks through headspace gas chromatography-Orbitrap high-resolution mass spectrometry. In view of the difficulties that may be encountered in the qualitative analysis of unknown substances, several typical cases and the corresponding reliable solutions are given from the perspective of comprehensive score and retention index, chemical ionization identification molecular formula, fragment ion detail comparison for distinguishing isomers, and identification of alkanes. With this method, 69 volatile substances were identified in 60 masks. The identified substances were divided into nine categories. Alkanes, esters, benzenes, and alcohols were the top four groups of substances identified in masks and accounted for 34.8%, 15.9%, 10.1%, and 7.2% of the total substances, respectively. In addition, ketones, ethers, phenolics, amides, and other substances were identified. Ethanol, 1,4-dichlorobenzene, toluene, m -xylene, dimethyl glutarate, and N,N-dimethylacetamide had high detection rates. The identified substances were further filtered and screened according to their detection rate, toxicity, and response intensity. Finally, 12 high-risk volatile chemicals in medical masks were listed. This study could serve as a reference for identifying unknown substances and a guide for monitoring volatile chemicals in masks and promoting chemical safety improvements in products.
研究领域:
分析化学
·
环境科学
·
毒理学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
Evidence-based Complementary and Alternative Medicine
·
2012
·
IF 4.774
Yuan-yuan Chai,Fang Wang,Yan-li Li,Ke Liu,Hui Xu
Rheum emodi Wall has been reported to possess protective effect in many inflammatory diseases and oxidative stress-related injuries. This study aims to investigate antioxidant power of stilbenoids from R. emodi and then explore the material basis for its antioxidant potential. The most abundant stilbenoid piceatannol-4′-O-β-D-glucopyranoside (PICG) and its aglycon piceatannol (PICE) were isolated from R. emodi rhizome. Using well-accepted antioxidant chemicals as reference, antioxidant activity of these stilbenoids was examined by measuring DPPH and superoxide anion radical scavenging, ferric reducing power, and inhibition of lipid peroxidation in vitro. Both PICG and PICE displayed promising antioxidant activity in all the four assays. Comparisons among the tested compounds indicated that PICE has the most potent antioxidant activity and the presence of 3′-hydroxyl group may enhance antioxidant activity of stilbenoids. The antioxidative effect of PICE at the cellular level was further demonstrated on the model of hydrogen-peroxide-induced H9c2 rat cardiomyoblasts injury. Taking into account the rapid in vivo metabolic transformation of PICG into PICE it can be inferred that the most abundant stilbenoid PICG may be an important constituent responsible for the antioxidant potential of R. emodi and promising to be developed as an antioxidant agent for supplementary or therapeutic use.
研究领域:
药理学
·
生物化学
·
药物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）