RAPID COMMUNICATIONS IN MASS SPECTROMETRY
·
2017
·Vol. 32
·期 4
·342-348
·
IF 1.998
Mengmeng Chen,Guohua Zhu,Jiaxiang Xu,Huarong Zhang,Jinsong Liu,Kezhi Jiang
Rationale Carcinogenic o -methylaniline is one of the banned aromatic amines in azo dyes, but it is very difficult to distinguish it from its noncarcinogenic isomers due to their identical retention time on chromatography and similar mass spectra. Methods Imidization of the isomeric methylanilines was carried out by treatment with benzaldehyde under mild conditions. The formed derivatives were analyzed by gas chromatography/mass spectrometry (GC/MS). Theoretical calculations were carried out on the Gaussian 03 program by using the density functional theory method at the B3LYP/6-311+G(d,p) level. Results Imidization of methylanilines occurred easily and gave rise to the corresponding N -methylbenzylidene benzenamines. The isomeric derivatives were completely separated by GC, and thus the three isomeric methylanilines could be determined simultaneously. Due to the ortho effect, the derivative from o -methylaniline has a characteristic fragment ion at m/z 118 with a stable bicyclic structure, and it could be easily differentiated from the meta - and para -isomers in electron ionization mass spectrometry. Conclusions These results provided a promising solution for simultaneous determination of isomeric methylanilines.
研究领域:
化学
·
毒理学
·
分析化学
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DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 62
·39127-39137
·
IF 3.108
Hao Wu,Xiao-Lin Chen,Xiang Huang,Hui-Min Ruan,Yan-Li Ji,Li-Fen Liu,Cong-Jie Gao
In this work, a novel semi-aromatic polyamide RO membrane was fabricated by using a new self-made dendritic molecule trimesoylamidoamine (TMAAM) as a key functional amine monomer that combined 1,3-diamino-2-propanol (DAP) to react with trimesoyl chloride (TMC) through interfacial polymerization technology. By adjusting the TMAAM concentration and amine-immersion mode, this new TMAAM-based semi-aromatic polyamide RO membrane exhibits simultaneously improved water permeability, antifouling and chlorine-tolerant properties. The introduced TMAAM units in polyamide chains can enhance the TMAAM-based membrane's water flux due to its dendritic structure as well as rich hydrophilic groups, and the DAP–TMAAM–TMC membrane prepared via the new two-step amine-immersion mode has 1.9 times more water flux without loss of salt rejection than the pristine DAP–TMC membrane and also shows higher water flux than the hand-cast conventional aromatic polyamide MPD–TMC membrane, respectively. At the same time, the regularly distributed hydroxyl groups and aliphatic amide bonds in TMAAM units contribute to the improved hydrophilicity and chlorine-tolerant property of the resultant DAP–TMAAM–TMC membrane, respectively. It is also demonstrated that the new two-step amine-immersion mode leads to a much smoother surface which endows the resultant DAP–TMAAM–TMC membrane with a favorable antifouling ability. This research provides us with a promising functional amine monomer and a new membrane formation method to fabricate a high performance RO membrane.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Xinyao Liu,Liangjie Wang,Feng Qian,Zhuolin Qing,Xiaolin Xie,Yonghui Song
Nitrogen-doped carbon materials can effectively activate peroxymonosulfate (PMS) to degrade organic pollutants. In this study, one or more of the following raw ingredients, ferric nitrate, dopamine hydrochloride and melamine, were used as raw materials to prepare different carbon-based catalysts. The different effects of each raw ingredient on the performance of the catalyst were studied. Characterization by X-ray diffract grams spectra, Raman spectroscopy and X-ray photoelectron spectroscopy found that Fe(NO 3 ) 3 ·9H 2 O in the catalyst is beneficial to promote the degree of graphitization, and melamine can increase the nitrogen content in the catalyst. The prepared Fe-DA-CN catalyst, prepared with three materials has the highest activity. When the catalyst dose was 50 mg/L and the PMS concentration was 0.25 mM, the removal rate of 5 mg/L sulfamethoxazole (SMX) reached more than 99% after 30 min of reaction; furthermore, the pH, presence of inorganic anions (HPO 4 2- , NO 3 – , CO 3 2– , Cl - ) and presence of humic acid had little effect on the SMX removal rate. Repeated use experiments show that the catalyst has good stability. Through electron paramagnetic resonance and quenching tests, it is found that the main active substances that activate PMS to degrade SMX are free radicals (·OH, SO 4 ·- ) bound on the catalyst surface and a small part of singlet oxygen ( 1 O 2 ).
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2023
·
IF 6.1
Qian Chen,Yuquan Pan,Chaochen Sun,Zongwen Wang,Yongning Wu,FengFu Fu
In reality, various sulfonamides (SAs) were alternately used in animal husbandry to avoid generating drug resistance. Thus, it is crucial to develop simple and high-throughput methods for detecting multiple or groups of SAs to realize rapid screening of total SAs residues in foods. We herein developed a sensitive and efficient MnO 2 nanosheets-mediated etching of gold nanobipyramids (AuNBPs), which can generate more vivid color changes, and further fabricated a high-throughput multicolor immunosensor for the visual screening/semi-quantitative detection of 6 different SAs including sulfamethazine (SMZ), sulfamethoxydiazine (SMD), sulfisomidine (SIM), sulfamerazine (SMR), sulfamonomethoxine (SMM) and sulfaquinoxaline (SQ) by using AuNBPs as signal and broad-specificity anti-SAs antibody as a bio-receptor. The immunosensor displays more vivid color changes, and has a lower visual detection limit and excellent specificity. It can be applied to detect as little as 1.0 ng/mL of SMZ, SMD, SMR and 2.0 ng/mL of SIM, SMM, SQ by bare eye observation, and 0.2 ng/mL of above 6 SAs by UV–visible spectrophotometry. The visual detection limit of the immunosensor is much lower than the maximum residue limit of total SAs (100 μg/kg) in edible tissues. The immunosensor was successfully applied to detect SMZ, SMD, SIM, SMR, SMM and SQ in milk with a recovery of 84%–106% and a RSD (n = 5) < 8%. The success of this study provided a promising assay for the on-site rapid screening of SMZ, SMD, SIM, SMR, SMM and SQ in food by bare eye observation. Importantly, the immunosensor may be expended as a general method for the visual screening/semi-quantitative detection of the group of other antibiotics by using the corresponding broad-specificity antibody as a bio-receptor.
研究领域:
分析化学
·
纳米技术
·
食品科学
·
免疫学
✓ 已验证
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Lifang Zhang,Wenting Yuan,Wangchao Zhao,Bo Yang,Xiaoqiao Jiao,Li Zhou,Shiqian Long,Jiwen Xu,Weilin Huang,Chenglin Liu,Guomao Zheng,Huizhong Shen,Jianhuai Ye,Lei Zhu,Tzung-May Fu,Xin Yang,Chen Wang
Carcinogenic nitrosamines have been widely studied due to their risk to human health. However, the universality and evolutionary processes of their generation, particularly concerning their secondary sources, remain unclear at present. We demonstrated through laboratory flow tube experiments that corresponding nitrosamines were generated from heterogeneous reactions of nitrous acid (HONO) with five structurally diverse amines commonly found indoors, including diphenylamine (DPhA), dibenzylamine (DBzA), dioctylamine (DOtA), N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD), and N-phenyl-1-naphthylamine (PANA). The heterogeneous reaction rate constants of DBzA and DOtA with HONO (∼70 ppb) were 1.21 × 10–3 and 2.13 × 10–3 min–1 at 30% relative humidity (RH), resulting in a lifetime of 13.8 and 7.8 h. As compared to higher RH (∼80%), more nitrosamines were produced from the reaction of HONO with surface-sorbed DBzA, DOtA, 6PPD, and PANA at lower RH (30%), with product yields ranging from <0.1% to 0.5%. Furthermore, we observed the formation of nitroso-6PPDs and nitro-6PPDs during room air exposure of 6PPD in a genuine indoor environment, in addition to various other transformation products indicative of reactions of 6PPD with HONO, NOx, and ozone indoors. This study confirmed the universality of the heterogeneous reaction of surface-sorbed amine with HONO as a source of nitrosamines indoors.
研究领域:
环境化学
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室内空气质量
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大气科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MINERALS ENGINEERING
·
2025
·
IF 5
Panxing Zhao,Wenbao Liu,Wengang Liu,Lingyun Bao,Yanbai Shen,Stephen Butt,Yahui Zhang
Removal of quartz from hematite by reverse flotation using cationic collectors is an effective approach for iron concentrate upgrading. In this paper, three hydroxyl-containing cationic collectors, i.e., N-Dodecylethanolamine (NDEA), N-Dodecylpropanolamine (NDPA), and N-Dodecylbutanolamine (NDBA), were synthesized and characterized. The flotation performance and the structure-performance relationship of the collectors were systematically investigated by micro-flotation experiments and various surface analysis techniques. At the concentration of 20 mg/L, the flotation recoveries of quartz by NDEA, NDPA, and NDBA were 94.9 %, 93.5 %, and 93.3 %, respectively. Collectors with shorter hydroxyl-substituted carbon chains exhibited stronger collecting ability and enhanced hydrophobicity of quartz surface, as confirmed by contact angle measurements. Zeta potential measurements and molecular simulations revealed that the collectors adsorb onto the quartz surface through electrostatic and hydrogen bonding interactions. The introduced hydroxyl groups could enhance the formation of hydrogen bonds between collectors and mineral surface. However, as the carbon chain length increases, the adsorption area of a single collector on the mineral surface increases, the number of collector molecules adsorbed per unit area decrease, reducing the collecting ability of the collector for quartz. This research could provide theoretical guidance for the design of novel cationic collectors.
研究领域:
矿物加工工程
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表面化学
✓ 已验证
产品关联
DOI
高影响因子
Polymer Chemistry
·
2016
·Vol. 7
·期 40
·6241-6249
·
IF 5.687
Junjie Yan,Rongrong Wang,Donghui Pan,Runlin Yang,Yuping Xu,Lizhen Wang,Min Yang
Fluorescent poly(amide-imide)s are promising materials for use in photonics due to their controllable optical properties and excellent flexibility. Although unconventional fluorescent polymers have been flourishing recently, the fluorescence of aliphatic poly(amide-imide)s has never been realized until now. Their poor solubility and intolerance to reactive groups during synthesis prohibit access for the modification of poly(amide-imide)s. Here, we synthesize a functional thiolactone-maleimide monomer via copper(I)-catalyzed azide alkyne cycloaddition and employ a strategy combining aminolysis of thiolactones and amine-maleimide Michael addition for the synthesis of fluorescent aliphatic poly(amide-imide)s with 2-aminosuccinimide fluorophores. Moreover, in situ generated thiols enable the poly(amide-imide)s to undergo facile PEGylation via a thiol–methacrylate Michael addition reaction to accomplish excellent solubility in organic solvents and in water.
研究领域:
材料科学
·
化学合成
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2014
·Vol. 38
·期 10
·4931-4937
·
IF 3.159
Wei Xu,Yu Wang,Su Liu,Jinghua Yu,Hongzhi Wang,Jiadong Huang
In this work, we report a novel sandwich-type electrochemical aptasensor for sensitive and selective detection of antibiotic kanamycin. This aptasensor was constructed by assembling graphene–polyaniline (GR–PANI) and polyamidoamine dendrimer–Au nanoparticle (PAMAM–Au) nanocomposites on the surfaces of a glass carbon electrode, which as electrode materials exhibited excellent charge-transport property and loading capacity of biomolecules. Followed by the sandwich-type specific identification, kanamycin detection was realized by outputting a redox current from electro-reduction reaction of H2O2 catalyzed by HRP. It was demonstrated that the developed strategy had a wide linear response range from 5 × 10−6 to 4 × 10−2 μg mL−1 and a low detection limit of 4.6 × 10−6 μg mL−1. Additionally, this aptasensor had the advantages in its low cost, high sensitivity, and superb specificity. Thus, it might provide a useful tool for kanamycin determination and related food safety analysis and clinical diagnosis.
研究领域:
分析化学
·
食品安全
·
临床诊断
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2018
·Vol. 42
·期 14
·12212-12221
·
IF 3.201
Yukun Sun,Dongyun Li,Hui Yang,Xingzhong Guo
Fe3O4@polydopamine@polyamidoamine (Fe3O4@PDA@PAMAM) core–shell nanocomposites were successfully fabricated through a monodispersed Fe3O4 nanoflower synthesis, PDA modification and PAMAM grafting. The as-prepared single Fe3O4@PDA@PAMAM nanocomposite possesses a high relevant saturation magnetization (Ms) (30.25 emu g−1), while the coercivity (Hc) (10.85 Oe) and retentivity (Mr) (0.9062 emu g−1) were extremely low. The obtained Fe3O4@PDA@PAMAM has an adsorption capacity as high as 97.18 mg g−1 for Cu(II), and the adsorption process is in conformity with pseudo-second-order kinetics and the Langmuir isotherm model. Moreover, the effect of pH and thermodynamics of the adsorption process is also discussed briefly.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2015
·Vol. 162
·期 10
·G87
·
IF 3.266
Hanli Ge,Yong Kong,Yan Pan,Linhong Deng,Dan Shou,Qingyun Lu
Dopamine was self-polymerized onto the surface of a glassy carbon electrode (GCE), and the obtained polydopamine (PDOA) functioned as a scaffold for the grafting of half-polyamidoamine (H-PAMAM) dendrimers, which is a new class of polymeric biomaterial as drug carriers. Aspirin was chosen as the model drug and loaded into the H-PAMAM dendrimers via ion pairing, hydrogen bonding and hydrophobic interaction. The synthesis of H-PAMAM dendrimers grafted PDOA was characterized by electrochemical impedance spectroscopy (EIS), attenuated total reflection infrared spectroscopy (ATR-IR), atomic force microscopy (AFM), transmission electron microscopy (TEM), UV-visible spectroscopy and water contact measurement. The process of aspirin loading and delivery was also monitored by EIS. The results demonstrate that PDOA films can be used as an excellent platform for grafting of H-PAMAM dendrimers, which is an ideal carrier for drug loading and delivery.
研究领域:
生物材料学
·
药剂学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2021
·
IF 3.498
Zhi-Juan Zhang,Peng-Wei Li,Lu-Ping Liu,Li-Hua Ru,Han-Xiao Tang,Wei-Sheng Feng
The analysis of breath VOC biomarkers is an efficient method for the early diagnosis of lung cancer. In this work, the zirconium UiO-66 was post-synthetically modified by using methylamine (MA), ethylenediamine (ED) and N,N′ -dimethylethylenediamine (MMEN), respectively. The modified UiO-66 materials were thoroughly characterized, including PXRD , FTIR, TGA , physical adsorption at 77 K by nitrogen and photoluminescence analysis. The sensing properties of the modified UiO-66 materials toward the selected five potential breath VOC biomarkers were investigated. Results showed that after modification, the BET surface area and total pore volume all decreased, and followed the order: UiO-66 > UiO-66-MA > UiO-66-MMEN > UiO-66-ED. Furthermore, the N–H group was successfully grafted into the modified UiO-66 samples. In comparison with UiO-66, the fluorescence intensities of UiO-66-MA, UiO-66-ED and UiO-66-MMEN toward hexanal , styrene and isoprene all obviously increased, while the fluorescence intensities of the modified UiO-66 materials toward 1-propanol and ethylbenzene all decreased a lot, accompanied by the frequency shift. In addition, the LOD of hexanal on UiO-66-MA was calculated to be as low as 12 ppm, which was obviously lower than that of UiO-66 (31 ppm). The fluorescence quenching of hexanal was mainly due to the FRET mechanism. The results of this study would provide information for the development of early breath diagnosis of lung cancer.
研究领域:
医学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2020
·
IF 3.862
Qingqing Ye,Baozhong Zhang,Yanhua Yang,Xiaoyu Hu,Yingzhong Shen
Two different aromatic diamines monomers (3, 5-diamino-N-(4'-phenyl-4''-triphenylamino)-N-(4''-benzyl-4'''-triphenylamino)benzamide (DPTBTB) and 3, 5-diamino-N-(4'-3'', 4'', 5''-trifluorobiphenyl)-N-(4''-benzyl-3''', 4''', 5'''-trifluorophenyl)benzamide (DTBTB)) containing flexible linkages were designed and synthesized, respectively. Four organo-solubility polyimides (PI-a, PI-b, PI-c, and PI-d) were prepared via a two-step procedure with pyromellitic dianhydride (PMDA) and 3, 3', 4, 4'-biphenyltetracarboxylic dianhydride (BPDA), respectively. The four PIs performed excellent thermal stability with the temperature of 5% weight loss in range of 370–420 ℃ at N 2 atmosphere. The Al/PI-a/ITO and Al/PI-b/ITO memory devices exhibited binary write-once-many-read (WORM) and rewritable (Flash) behavior, respectively. But the Al/PI-c/ITO and Al/PI-d/ITO memory devices showed ternary WORM and Flash behavior due to the deeper charge traps came from the fluorinated groups in the structure of PI-c and PI-d, respectively. The memory switching mechanism could be demonstrated through molecular simulation. The results gave an effective strategy that adjusting the structure of PI to achieve different memory effects.
研究领域:
材料科学
·
电子工程
✓ 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）