RAPID COMMUNICATIONS IN MASS SPECTROMETRY
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2021
·Vol. 36
·期 3
·e9218
·
IF 2.419
Mengying Du,Kailin Zhang,Luyang Jiao,Yicheng Xu,Xianglei Kong
Rationale The challenge of glycan identification due to their structural complexity and diversity has profited enormously from recent developments in mass spectrometry (MS)-related methods. For photodissociation MS, infrared (IR) and ultraviolet (UV) lasers can generate complementary fragment ions, so an effective combination of the two methods may provide rich and valuable fragmentation patterns for glycan analysis. Methods A 7.0 T Fourier transform ion cyclotron resonance (FTICR) mass spectrometer equipped with a double-beam laser system was applied for the experiments. 3,5-Diiodo-L-tyrosine was selected as the assistant molecule to form complex ions with ten isomeric disaccharides through electrospray ionization. The complex ions were further isolated and irradiated by IR and UV lasers separately or continuously in the FTICR cell. Results By combining the two complementary fragment spectra generated from the IR and UV lasers, a clear identification of all the ten isomers was achieved using their binary codes based on their fragmentation patterns. The double-beam method simplifies the experiment by introducing the two lasers sequentially in one experiment, providing richer fragmentation patterns and making the full discrimination easier. Conclusions This study demonstrates the capabilities of the combination of IR and UV photodissociation MS in the identification of diverse glycan isomers. The double-beam photodissociation method described here distinguished compositional, configurational and connectivity disaccharide isomers successfully. Compared with the data accumulation method based on separate IR and UV experiments, this method is simpler, faster, more flexible and also characterized by richer fragmentation patterns.
研究领域:
生物化学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2020
·
IF 5.778
Chao Song,Kai-Xin Zhang,Xiao-Juan Wang,Shan Zhao,Shu-Guang Wang
The residues of tetracycline in environment have raised increasing concern for the deleterious impact on ecological and human health. Natural organic matter (NOM), ubiquitous in natural waters, is unavoidable to encounter tetracycline, which might affect the fate of tetracycline in aquatic environment. In this study, we investigated the effect of natural organic matter (NOM) on the photolytic fate of tetracycline (TC). The photolysis kinetics of TC were evaluated with two representative NOM, tannic acid (TA) and gallic acid (GA). The presence of TA and GA obviously inhibited the removal of TC under UV irradiation with photolysis rate constant at 0.067 h −1 and 0.071 h −1 , respectively, which were 32.3% and 28.3% less than that without TA and GA (0.099 h −1 ). Furthermore, NOM exhibited different impacts on both indirect photolysis and direct photolysis. NOM promoted the formation of hydroxyl radical , induced the generation of triplet-excited state NOM and thus greatly enhanced the indirect photolysis of TC. However, direct photolysis was almost completely inhibited by NOM via inner filter effect and interacting with TC to form ground-state complex with low photoreactive. Moreover, similar intermediates were detected in the presence and absence of NOM, indicating that NOM exhibited limited influence on the degradation pathways of TC. This study reveals the multiple roles of NOM on tetracycline photolysis, contributing to better understand the photolytic fate of antibiotics in natural waters.
研究领域:
环境科学
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水污染控制
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生态毒理学
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2019
·Vol. 9
·期 8
·1143
·
IF 4.034
Hai-Tao Ren,Jing Han,Ting-Ting Li,Qi Lin,Jia-Horng Lin,Ching-Wen Lou
The fate of arsenic in the water environment is of great concern. Here, the influences of oxalic acid and UV light illumination on the dissolution of naked ferrihydrite (Fhy), Fhy loaded with As(V) [Fhy*-As(V)], as well as the fate of As(V) at pH 3.0 were studied. With the assistance of oxalic acid, complexes of Fe(III)-oxalic acid produced on Fhy/Fhy*-As(V) were reduced to Fe(II)-oxalic acid by photo-induced electrons under UV light irradiation. UV light has nearly no impact on the release of As(V) in the system of Fhy*-As(V) without the assistance of oxalic acid. Nevertheless, in the existence of oxalic acid, UV light illumination resulted in the contents of liberated As(V) decreased by 775–1300% compared to that without light. Considering the coexistence of As(V), oxalic acid as well as iron oxides in aquatic environments, the present study revealed that UV illumination could enhance the retention of As(V) on Fhy in the acidic water environment containing oxalic acid.Keywords:ferrihydrite;As(V);photodissolution;oxalic acid;fate
研究领域:
环境科学
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化学
✓ 已验证
DOI
PubMed
高影响因子
Royal Society Open Science
·
2019
·Vol. 6
·期 5
·
IF 2.515
Pingfeng Fu,Gen Li,Xiaoting Wu,Xiaofeng Lin,Bolan Lei
The decomposition of toxic flotation reagents upon UV185+254 nm irradiation was attractive due to operational simplicity and no dosage of oxidants. In this work, the degradation of typical thiol collectors (potassium ethyl xanthate (PEX), sodium diethyl dithiocarbamate (SDD), O-isopropyl-N-ethyl thionocarbamate (IET) and dianilino dithiophoshoric acid (DDA)) was investigated by UV185+254 nm photolysis. The degradation efficiencies and mineralization extents of collectors were assessed. The formation of CS2 and H2S byproducts was studied, and the mechanisms of collector degradation were proposed under UV185+254 nm irradiation. The PEX, SDD and IET were decomposed with nearly 100% removal upon 75 min of UV185+254 nm irradiation. The decomposition rate constants decreased in the order SDD > PEX > IET ≫ DDA, and the DDA was the refractory collector. After 120 min of UV185+254 nm irradiation, 15−45% of carbon and 25−75% of sulfur of collectors were completely mineralized, and the mineralization extent decreased in the order PEX > SDD > IET > DDA. The percentage of gaseous sulfur (CS2 and H2S) ranged from 0.48 to 4.85% for four collectors, showing the fraction of emitted sulfur byproducts was small. The aqueous CS2 concentration increased in the first 10−20 min, and was decreased to a low level of 0.05–0.1 mg l−1 at 120 min. Two mechanisms, i.e. direct UV254 nm photolysis and indirect oxidation with free radicals, were responsible for collector decomposition in the UV185+254 nm photolysis.
研究领域:
环境科学
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化学工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2022
·
IF 5.895
Yuan Shi,Xiaokang An,Binbin Zhang,Xinglu Pan,Xiaohu Wu,Jun Xu,Wensheng Xiang,Fengshou Dong,Xiangjing Wang,Yongquan Zheng
Guvermectin is a biopesticide isolated from the secondary metabolites of Streptomyces sp. NEAU6, an endogenous actinomyces of a Chinese medicine named Paris polyphylla. However, the environmental degradation behavior and biotoxicity of guvermectin are still unclear, which may affect its rational application. Therefore, the degradation of guvermectin in water at different pH values (pH 4, pH 6, pH 7, and pH 9) and with or without light was investigated in the laboratory. The results showed that guvermectin could be degraded in pH 4 solution, and the presence of light irradiation enhanced the degradation process with a DT50 of 2.95 and 12 days for photolysis and hydrolysis, respectively. However, guvermectin was fairly stable in other conditions. Three products transformed from guvermectin degradation were identified by UPLC-QTOF/MS. Biotoxicity assessment was performed on Danio rerio and Daphnia magna Straus by ECOSAR prediction and in vivo biological tests. The test data showed that guvermectin and its transformation products exhibited low toxicities to D. rerio and D. magna Straus (LC50/EC50 > 100 mg a.i./L), and the transformation products had lower toxicity than their parent substance. The results provided a reference for elucidating the potential risk of guvermectin to nontarget organisms and promoting its rational use.
研究领域:
环境科学
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毒理学
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农药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Environmental Research and Public Health
·
2017
·Vol. 14
·期 12
·1564
·
IF 2.101
Wenchao Liao,Virender K. Sharma,Su Xu,Qingsong Li,Lei Wang
Degradation of norfloxacin (NOR) was studied using a combination of microwave and UV irradiation methods (MW/UV process). Remarkable synergistic effect was found between MW and UV light. The removal rate with the MW/UV process was much faster than that with UV light irradiation only. Degradation of NOR followed second-order kinetics and ~72% of NOR could be removed in the first 5 min of MW/UV reaction. Influence of inorganic ions (cations (K+, Mg2+, Ca2+, Cu2+) and anions (Cl−, SO42−, NO3−, CO32−)), humic acid (HA) and surfactants (cation, anion, and non-ionic) on the degradation of NOR by the MW/UV process was investigated. Among the ions, Cu2+and NO3−ions inhibited the degradation of NOR. The presence of HA and surfactants in water showed a slight inhibition on the NOR removal. Furthermore, the NOR degradation in the MW/UV process was primarily caused by the ·OH-photosensitization steps. Seven intermediates formed by the oxidation of NOR were identified and three reaction pathways were proposed. Removals of NOR in tap water (TW), synthetic wastewater (WW), river water (RW), and seawater (SW) were also studied, which demonstrated that the MW/UV process was an effective oxidation technology for degrading fluoroquinolone antibiotics in different water matrices.Keywords:antibiotics;photolysis;oxidation;microwave;synergistic effect
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Yiqun Gan,Shengcun Ma,Xiaoqi Guo,Baiyang Chen,David Jassby
Chloral hydrate (CH) is a common disinfection by-product found in treated water, and its effective control is important to human health. This study evaluated the effects of some environmental factors (e.g., pH, CH dosage, typical ions) and operational variables (e.g., lamp power, irradiation time) on CH photolysis efficiency via low-pressure mercury lamp–induced ultraviolet (LPUV) at 254 nm. The results demonstrated that the photolysis rate increased significantly with increasing pH from 7.0 to 10.5 and lamp power from 6 to 12 W. Meanwhile, the presence of nitrate, iodide, or free chlorine facilitated CH photolysis, whereas the existence of natural organic matter hindered the process. Together, these factors may help explain varying CH photolysis in different types of waters: seawater > ultrapure water > tap water > lake water. In addition, the initial CH dosage also played an important role, with higher CH being degraded more slowly. Mechanistically, although no catalyst or oxidant was added, CH photolysis was to some extent inhibited by a hydroxyl radical quencher, tert -butyl alcohol, suggesting that indirect photolysis was also responsible for CH loss. In terms of reaction products, the CH photolysis yielded primarily chloride ions and carbon dioxide, thus supporting mineralization as the key pathway. The results may help better understand the control of CH in water using UV.
研究领域:
环境科学
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水处理工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Inorganic Chemistry Frontiers
·
2021
·Vol. 8
·期 16
·3863-3870
·
IF 6.569
Yuwei Zhang,Lina Wang,Xiaoxiang Xu
CuBi2O4 and CuWO4 films (2 × 2 cm) on an FTO substrate have been fabricated to construct an all-copper-based oxide tandem cell for solar-driven photoelectrochemical (PEC) water splitting. CuBi2O4 and CuWO4 films are of opposite semiconductivity, and exhibit a large difference in the onset potentials and matched light absorption, making them ideal for a tandem configuration for solar energy conversion. Under optimal conditions, the tandem cell (4 cm2) exhibits a water splitting photocurrent of 0.3 mA without an external bias under simulated solar insolation. The low cost, non-toxicity, good stability and easy manufacture of this copper-based oxide tandem cell warrant promising applications in the field of solar energy conversion.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2023
·
IF 12.8
Yifei Zhang,Zhechao Hua,Xuewen Zhang,Kaiheng Guo,Jingyun Fang
Solar photolysis of free chlorine (solar/chlorine) in bromide-containing water occurs under various scenarios, such as chlorinated reservoirs and outdoor swimming pools, and the formation of chlorate and bromate is an important issue in the system. We reported unexpected trends for the formation of chlorate and bromate in the solar/chlorine system. Excess chlorine inhibited the formation of bromate, i.e., increasing chlorine dosages from 50 to 100 μM reduced the bromate yield from 6.4 to 1.2 μM in solar/chlorine at 50 μM bromide and pH 7. The yield of bromate in solar/chlorine at 100 μM chlorine and 50 μM bromide in 240 min was 18.8% of that at 50 μM bromine only. The underlying mechanism was that HOCl can react with bromite (BrO 2 − ) to form HOClOBrO − , whose multi-step transformation finally formed chlorate as the major product and bromate as the minor product. This reaction overwhelmed the oxidation of bromite to form bromate by reactive species, such as • OH, BrO • and ozone. On the other hand, the presence of bromide greatly enhanced the formation of chlorate. Increasing bromide concentrations from 0 to 50 μM enhanced the chlorate yields from 2.2 to 7.0 μM at 100 μM chlorine. The absorbance of bromine was higher than that of chlorine, thus the photolysis of bromine formed higher levels of bromite at higher bromide concentrations. Then, bromite rapidly reacted with HOCl to form HOClOBrO − and it further transformed to chlorate. Additionally, 1 mg L − 1 NOM had a negligible effect on bromate yields in solar/chlorine at 50 μM bromide, 100 μM chlorine and pH 7. This study demonstrated a new pathway of chlorate and bromate formation in the solar/chlorine system with bromide.
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2021
·
IF 11.236
Lixiao Wang,Yajie Zheng,Yiran Zhou,Junhe Lu,Jean-Marc Chovelon,Yuefei Ji
Ketoprofen (KTF) is a nonsteroidal anti-inflammatory drug frequently detected in natural and engineering waters. Because KTF is particularly photolabile (half-life ∼4 min), knowledge of the fate and ecological risks of KTF photoproducts in the aquatic environment is especially essential. Herein, we systematically investigated the photophysics, photochemistry , and photosensitization of KTF photoproducts in aqueous solution under 365 nm irradiation (UV 365 ). Results show that KTF photolyzed rapidly and formed 3-ethyl- α -hydroxylbenzophenone (EtOH-BP), 3-ethyl- α -hydroperoxylbenzophenone (EtOOH-BP), 3-acetylbenzophenone (AcBP), and 3-ethylbenzophenone (EtBP), as identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and high-resolution mass spectrometry (HRMS). The presence of O 2 significantly affected the evolution of photoproducts during KTF photolysis. The photophysical properties of EtBP and AcBP were characterized by spectroscopic approaches. In particular, transient absorption spectra obtained by nanosecond laser flash photolysis (LFP) indicated that EtBP and AcBP were excited to triplet states with lifetimes of 28 and 2.4 µs, respectively. EtBP underwent further photodegradation , giving rise to EtOH-BP, EtOOH-BP, and AcBP upon UV 365 irradiation. The reaction is proposed to proceed through an excimer precursor ( 3 [EtBP···EtBP]*) followed by intramolecular H-abstraction. In contrast, AcBP was relatively photostable, particularly under aerated condition. Both EtBP and AcBP have strong photosensitizing activity, as evidenced by the triplet probe 4-( N,N -dimethylamino)benzonitrile (DMABN). ECOSAR program suggested that the photoproducts are more ecotoxic and bioaccumulative than the parent KTF. Results of this study underscore the need to scrutinize the formation and fate of KTF photoproducts in sunlit surface waters.
研究领域:
环境科学
·
光化学
·
毒理学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2022
·
IF 10.753
Shengyan Jin,Lingdong Kong,Kejing Yang,Chao Wang,Lianghai Xia,Yuwen Wang,Jie Tan,Lin Wang
Free radicals and nitrogen-containing species produced by nitrate photolysis can affect various atmospheric chemical processes, and thereby the photochemical behavior of atmospheric nitrate aerosols has been attracting much attention. However, the photolysis mechanism of NH 4 NO 3 and its products under different atmospheric conditions remain unclear. In this study, the effects of relative humidity (RH), pH, NH 3 , ultraviolet (UV) light intensity and halogen ions (Cl − , Br − and I − ) on the photolysis of particulate NH 4 NO 3 have been investigated through a flow tube reactor. The results show that RH can significantly enhance the production of gaseous NO 2 from the photolysis of NH 4 NO 3 when RH is higher than its deliquescence RH, but almost no NO 2 is generated under dry conditions. Under high RH and UV light, the main product of NH 4 NO 3 photolysis is NO 2 , rather than NO and HONO, and another main species HNO 3 which mainly comes from the hydrolysis of product NO 2 in the gas path was detected. Almost no NO 2 and HNO 3 are produced under high RH without UV light or low RH with UV light, showing the combined effect of high RH and UV irradiation on the photolysis of NH 4 NO 3 . In addition, under high RH, the lower the pH and the stronger the light intensity, the higher the NO 2 production. Furthermore, surprising yields of NO and HONO are detected in the presence of halogen ions, especially in the presence of I − , indicating the important role of halogen ion in the nitrate photolysis. These results provide new insights into the photolysis of atmospheric nitrate aerosols, and may contribute to elucidating the formation and migration of atmospheric nitrate aerosols and the potential mechanisms of the occurrence and evolution of atmospheric pollution and ozone pollution.
研究领域:
大气化学
·
环境科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Hong-Si Guo,Wenfeng Zhao,Qingmei Ge,Nan Jiang,Mao Liu,Hang Cong
A promising method for producing hydrogen from solar energy and converting it into chemical fuels is photoelectrochemical (PEC) water splitting. In this paper, a novel photoanode is prepared by hydrothermal growing of nanorod CdS/g-C 3 N 4 /Q[7] heterojunction on FTO substrate for photoelectrochemical water splitting to produce hydrogen. In this method, Q[7]-doped g-C 3 N 4 is tightly combined with CdS composite and substrate, which significantly improves the separation and migration of photogenerated carriers in g-C 3 N 4 /Q[7] and CdS, and effectively reduces the internal resistance of the photoanode. Compared with the free CdS NRs, the PEC performance of the heterojunction CdS/g-C 3 N 4 /Q[7]-10 is significantly enhanced with the improved photocurrent density of 1049.7 μA/cm 2 under AM 1.5 G (100 mW/cm 2 ) simulated sunlight, which is 3.6 times that of pristine CdS and 2.6 times that of FTO-CdS/g-C 3 N 4 under the same conditions. The external bias photocurrent conversion efficiency and photohydrogen conversion efficiency of CdS/g-C 3 N 4 /Q[7]-10 photoanode at 0.7 V (relative to RHE) are measured to be both 0.31 %, as 3.1 times high as that of the original CdS NRs (0.10 %), and 2.07 times high as that of FTO-CdS/g-C 3 N 4 (0.15 %). The generation of heterostructure with interfacial interaction reduces the recombination of photogenerated electron-hole pairs, to enhance the charge transfer of water oxidation kinetics, allowing electrons to quickly transfer through the external circuit to the counter electrode for H + reduction to produce H 2 . A schematic diagram of the photoelectrochemical water splitting hydrogen evolution process with the heterojunction CdS/g-C 3 N 4 /Q[7]-10 is systematically proposed.
研究领域:
材料科学
·
能源转换
·
光电化学
✓ 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）