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Pr/N co-doped biomass carbon dots with enhanced fluorescence for efficient detection of 2,4-dinitrophenylhydrazine
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作者 SUN Xuehua MA Min +4 位作者 LIU Jianting TIAN Rui CHAI Hongmei CUI Huali GAO Loujun 《无机化学学报》 北大核心 2025年第3期561-573,共13页
We used the natural product chamomile as a carbon source to synthesize praseodymium(Pr) and nitrogen(N) co-doped biomass carbon dots(Pr/N-BCDs) with remarkable luminescence properties by one-step hydrothermal method.C... We used the natural product chamomile as a carbon source to synthesize praseodymium(Pr) and nitrogen(N) co-doped biomass carbon dots(Pr/N-BCDs) with remarkable luminescence properties by one-step hydrothermal method.Compared with single N-doped BCDs(N-BCDs) and Pr-doped BCDs(Pr-BCDs),Pr/N-BCDs not only showed better fluorescence properties and stability but also achieved a significant increase in quantum yield of 12%.More importantly,under certain conditions,Pr/N-BCDs and 2,4-dinitrophenylhydrazide(2,4-DNPH) had significant fluorescence internal filtration effect(IFE) and dynamic quenching effect,and in the concentration range of0.50-20 μmol·L^(-1),the concentration of 2,4-DNPH had a good linear relationship with the fluorescence quenching signal,and the detection limit was as low as 2.1 nmol·L^(-1). 展开更多
关键词 co⁃doped carbon dots 2 4⁃DNPH fluorescence detection
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Spectrophotometric Determination of Chlordiazepoxide Using Its Charge-transfer Complex with 2,4-Dinitrophenol 被引量:3
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作者 李彦威 赵彦生 +1 位作者 宣春生 魏文珑 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第4期196-199,共4页
A new simple, rapid and sensitive spectrophotometric method for the determination of chlordiazepoxide is described, based on the reaction with 2,4-dinitrophenol in water medium, apparently by a charge-transfer mechani... A new simple, rapid and sensitive spectrophotometric method for the determination of chlordiazepoxide is described, based on the reaction with 2,4-dinitrophenol in water medium, apparently by a charge-transfer mechanism, to yield 1:1 complex with maximum absorption at 444 nm. Optimum experimental conditions for the determination have been studied. The linear calibration range, apparent molar absorptivity and relative standard deviation are 2.8~96.0 mgmL-1, 1.48103 and 0.32%, respectively. The method is accurate and has been successfully applied to the determination of chlordiazpoxide in tablets. The results are in good agreement with those obtained with the official method. 展开更多
关键词 CHLORDIAZEPOXIDE 2 4-dinitropheNOL Charge-trandfer reaction SPECTROPHOTOMETRY
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An Abnormal Reaction of N- (2,4-dinitrophenyl)-L-proline with Thionyl Chloride
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作者 Zhi Bin +3 位作者 XU Zong Ru GUO 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第2期133-134,共2页
N- (2,4-Dinitrophenyl)-4-amino-n-butyl aldehyde 3 was obtained with high yield of 80% when N- (2,4-dinitrophenyl)-L-proline 1 reacted with SOCl2 at room temperature. However, the anticipated product N- (2,4-dinitroph... N- (2,4-Dinitrophenyl)-4-amino-n-butyl aldehyde 3 was obtained with high yield of 80% when N- (2,4-dinitrophenyl)-L-proline 1 reacted with SOCl2 at room temperature. However, the anticipated product N- (2,4-dinitrophenyl)-tetrahydropyrrolyl-2- (4-methylthiophenyl) ketone 2 did not be produced. The mechanism was discussed in this article. 展开更多
关键词 L-PROLINE 1-fluoro-2 4-dinitrobenzene(FDNB) N-(2 4-dinitrophenyl)-4-amino-n-butyl aldehyde.
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Adsorption of 2,4-dinitrophenol and 2,4-dichlorophenol on Cationic Surfactant Modified Red Soil 被引量:3
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作者 廖敏 《Chinese Journal Of Geochemistry》 EI CAS 2004年第4期301-308,共8页
Adsorption isotherms of 2,4-dinitrophenol and 2,4-dichlorophenol on hexadecyltrimethylammonium (HDTMA) bromide modified red soil under different ionic strength, divalent cation Cu 2+ or different pH conditions were st... Adsorption isotherms of 2,4-dinitrophenol and 2,4-dichlorophenol on hexadecyltrimethylammonium (HDTMA) bromide modified red soil under different ionic strength, divalent cation Cu 2+ or different pH conditions were studied. All the adsorption isotherms were well fitted to the Freundlich equation. The adsorption capacities of 2,4-dinitrophenol or 2,4-dichlorophenol were dramatically enhanced by HDTMA treatment of red soil. The increase of ionic strength and the addition of divalent heavy metal cation Cu 2+ significantly enhanced the adsorption of 2,4-dinitrophenol or 2,4-dichlorophenol on the HDTMA-modified red soil. Adsorption capacities of HDTMA-modified red soil for 2,4-dinitrophenol and 2,4-dichlorophenol gradually increased with decreasing pH in the aqueous phase. 展开更多
关键词 2 4-二硝基酚 2 4-二氢氯化 红土 阳离子表面活性剂
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An Explosive Organic/Inorganic Hybrid: Synthesis and Thermal Property of Octa(2,4-dinitrophenyl)silsesquioxane 被引量:6
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作者 CHENHong-Ji 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第1期42-45,共4页
Octaphenylsilsesquioxane(OPhS) was prepared by a modifying method and a new core-shell nanocomposite, octa(2,4-dinitrophenyl)silsesquioxane, [(R_2PhSiO_ 1.5)_8, R=—NO_2, ODNPhS], was synthesized by nitration of OPh... Octaphenylsilsesquioxane(OPhS) was prepared by a modifying method and a new core-shell nanocomposite, octa(2,4-dinitrophenyl)silsesquioxane, [(R_2PhSiO_ 1.5)_8, R=—NO_2, ODNPhS], was synthesized by nitration of OPhS in a mixed acid solution of nitric and sulfuric acids at about 60 ℃. Their molecular structures were determined by DRIFTS, 1H NMR, 13C NMR spectra analysis. The thermal analysis shows that ODNPhS is an explosive that detonates at about 420 ℃. 展开更多
关键词 Core-shell nanocomposite Organic/inorganic hybrid Octa(2 4-dinitrophenyl)silsquioxane Thermal property
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Evaluation of efficacy of resin hemoperfusion in patients with acute 2,4-dinitrophenol poisoning by dynamic monitoring of plasma toxin concentration 被引量:3
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作者 Xue-hong ZHAO Jiu-kun JIANG Yuan-qiang LU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2015年第8期720-726,共7页
Objective: The intoxications caused by 2,4-dinitrophenol (2,4-DNP), even death, have been frequently reported in recent years. This study aims to investigate the dynamic changes of plasma toxin concentration and ex... Objective: The intoxications caused by 2,4-dinitrophenol (2,4-DNP), even death, have been frequently reported in recent years. This study aims to investigate the dynamic changes of plasma toxin concentration and explore the clinical value of resin hemoperfusion (HP) in the treatment of patients with acute 2,4-DNP poisoning. Methods We reported 16 cases of acute 2,4-DNP poisoning through occupational exposure due to ignoring the risk of poisoning. The blood samples were collected from the 14 survivors. According to the different treatments of resin HP, the survivors were divided into routine HP (n=5) and intensive HP (n=9) groups. Ultra high performance liquid chromatography/ tandem mass spectroscopy (UPLC-MS/MS) was used to detect the 2,4-DNP concentration in plasma in this study. Results: The 14 survivors recovered very well after treatment. The initial plasma 2,4-DNP concentrations (C1) of survivors ranged from 0.25 to 41.88 pg/ml (mean (12.56+13.93) pg/ml). A positive correlation existed between initial plasma 2,4-DNP concentration (C1) and temperature. The elimination of 2,4-DNP was slow and persistent, and the total clearance rates of plasma toxin from the 1st to 3rd day (R3), the 3rd to 7th day (R3-7), and the 1st to 7th day (RT), were only (53.03±14.04)%, (55.25±10.50)%, and (78.29±10.22)%, respectively. The plasma toxin was cleared up to 25 d after poisoning in most of the patients. The R3, R3-7, and R7 in the intensive HP group were all apparently higher than those in the routine HP group, with statistical significance (P〈0.05). Simultaneously, the elimination half-life (tl/2) of 2,4-DNP in the intensive HP group was apparently shorter than that in the routine HP group, with statistical significance (P〈0.05). Conclusions: The clinicians should be aware of this slow and persistent process in the elimination of plasma 2,4-DNP. Higher initial plasma toxin concentration resulted in a more severe fever for the patient. According to the limited data, longer and more frequent resin HP may accelerate to eliminate the poison. 展开更多
关键词 2 4-dinitropheNOL POISONING HEMOPERFUSION PHARMACOKINETICS THERAPEUTICS
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Clinical features and treatment in patients with acute 2,4-dinitrophenol poisoning 被引量:2
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作者 Yuan-qiang LU Jiu-kun JIANG Wei-dong HUANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2011年第3期189-192,共4页
Objective:To report clinical features and treatment of 16 cases of acute 2,4-dinitrophenol poisoning. Methods:A total of 16 patients suffering from acute poisoning due to non-oral exposure to 2,4-dinitrophenol were se... Objective:To report clinical features and treatment of 16 cases of acute 2,4-dinitrophenol poisoning. Methods:A total of 16 patients suffering from acute poisoning due to non-oral exposure to 2,4-dinitrophenol were sent to our hospital.Two died within 3 h after admission,while the other 14 responded to supportive treatment and he-moperfusion.Clinical features and treatment of the patients were retrospectively analyzed and presented.Results:Fourteen patients recovered and were discharged after four to six weeks of treatment.No obvious poisoning sequelae were found in the three-month follow-up.Conclusions:Non-oral exposure to 2,4-dinitrophenol is toxic.Hemoperfusion and glucocorticoid treatments may be efficient measures to prevent mortality,but this requires further study. 展开更多
关键词 2 4-dinitrophenol POISONING THERAPEUTICS HEMOPERFUSION GLUCOCORTICOID
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Early Changes of Peripheral Blood Lymphocyte Subpopulations in Patients with Occupational 2,4-dinitrophenol Poisoning 被引量:4
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作者 JIANG Jiu Kun FANG Wen +1 位作者 GU Lin Hui LU Yuan Qiang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第12期909-914,共6页
2,4-dinitrophenol (DNP), an organic compound which frequently used in industry, is considered to have high toxicity. This study aimed to investigate the early changes of lymphocyte subpopulations in patients with oc... 2,4-dinitrophenol (DNP), an organic compound which frequently used in industry, is considered to have high toxicity. This study aimed to investigate the early changes of lymphocyte subpopulations in patients with occupational 2,4-DNP poisoning. Totally 9 patients with acute occupational 2,4-DNP poisoning and 30 healthy volunteers as control were enrolled. The patients received immediately comprehensive supportive treatments, including large-dose glucocorticoid and repeated hemoperfusion (HP). The ratio of CD4+/CD8+ T cells were significantly higher in patients upon admission compared to healthy controls (P 〈 0.01); however, counts of total lymphocytes, CD3+, CD3+CD4+, CD3+CD8+, B (CD19+), and natural killer (NK) cells (CD16+CD56+) were significantly reduced (all P 〈 0.001). The NK cell count was negatively correlated with initial plasma 2,4-DNP concentration (r = -0.750, P = 0.026). Thus, acute occupational 2,4-DNP poisoning was accompanied by immediate complex immune cell reactions, especially NK cells might play important role in severe 2,4-DNP poisoning. 展开更多
关键词 DNP Early Changes of Peripheral Blood Lymphocyte Subpopulations in Patients with Occupational 2 4-dinitrophenol Poisoning
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Rapid, simple and selective determination of 2,4-dinitrophenol by molecularly imprinted spin column extraction coupled with fluorescence detection 被引量:4
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作者 Min Fang Fang Lei +2 位作者 Jia Zhou Yong-Ning Wu Zhi-Yong Gong 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第11期1492-1494,共3页
A rapid, simple and selective method based on molecularly imprinted, spin column extraction coupled with fluorescence detection was successfully established for the determination of 2,4-dinitrophenol in serum samples.... A rapid, simple and selective method based on molecularly imprinted, spin column extraction coupled with fluorescence detection was successfully established for the determination of 2,4-dinitrophenol in serum samples. The 2,4-dinitrophenol imprinted polymers exhibited highly selective recognition for the template molecule and the maximum adsorption capacity was 138.9 mg/g. The results indicated that when water is used as the loading solution, only 2,4-dinitrophenol could be adsorbed on the spin column without the remaining structural analogs(2-nitrophenol, 4-nitrophenol and phenol). After eluting with acetonitrile/acetic acid(9/1, v/v), 2,4-dinitrophenol in serum samples could be determined by using the fluorescence spectrometer, based on the fluorescence enhancement of fluorescein by the template molecule. Under the optimal conditions, the spiked recovery ranged from 95.8% to 103.4% and the detection limit was 1 nmol/L. The results confirmed the reliability and practicality of the protocol and revealed a good perspective of this method for biological sample analysis. 展开更多
关键词 Molecularly imprinted solid phase extraction Indirect fluorescence detection Spin column 2 4-dinitrophenol
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Practical Chemoselective Aromatic Substitution:Highly Efficient Dinitrification of N-Phenylbenzenesulfonamide for Synthesis of N-(2,4-dinitrophenyl)benzenesulfonamide
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作者 Xu Xiaobo Yu Xiao +1 位作者 Xia Chengcai Ji Yafei 《有机化学》 SCIE CAS CSCD 北大核心 2024年第9期2915-2923,共9页
A novel route for dinitrification of N-phenylbenzenesulfonamide to synthesize N-(2,4-dinitrophenyl)benzenesulfonamide has been developed.The method features convenient operation and good functional group tolerance.Thi... A novel route for dinitrification of N-phenylbenzenesulfonamide to synthesize N-(2,4-dinitrophenyl)benzenesulfonamide has been developed.The method features convenient operation and good functional group tolerance.This reaction may go through a nitrogen dioxide radical(NO_(2)·)intermediate,which is generated by the thermal reaction process of sodium nitrate and ammonium persulfate.In addition,it provides direct approach for the preparation of 2,4-dinitroaniline derivatives which are crucial intermediate for the synthesis of benzimidazoles and quinoxaline derivatives. 展开更多
关键词 N-phenylbenzenesulfonamide dinitrification N-(2 4-dinitrophenyl)benzenesulfonamide
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氨氯吡啶酸、二氯吡啶酸和2,4-滴二甲胺盐在天然草原土壤和牧草中的消解动态 被引量:1
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作者 牛树君 王玉灵 +3 位作者 赵峰 余海涛 张新瑞 胡冠芳 《植物保护》 北大核心 2025年第2期141-146,共6页
除草剂混用组合2,4-滴二甲胺盐+氨氯·二氯能兼防天然草原狼毒Stellera chamaejasme、披针叶野决明Thermopsis lanceolata和黄花棘豆Oxytropis ochrocephala等多种毒草,施用除草剂后的安全放牧时间对确保家畜安全至关重要。本文采... 除草剂混用组合2,4-滴二甲胺盐+氨氯·二氯能兼防天然草原狼毒Stellera chamaejasme、披针叶野决明Thermopsis lanceolata和黄花棘豆Oxytropis ochrocephala等多种毒草,施用除草剂后的安全放牧时间对确保家畜安全至关重要。本文采用超高效液相色谱串联质谱检测方法,研究了甘肃省肃南县天然草原土壤和牧草中二氯吡啶酸、氨氯吡啶酸和2,4-滴二甲胺盐的残留消解动态,旨在确定施用除草剂后的安全放牧时间,并评价其在土壤和牧草中的残留期长短,为制定农药最大残留限量标准提供参考。结果表明,二氯吡啶酸、氨氯吡啶酸和2,4-滴二甲胺盐在天然草原土壤和牧草中的残留消解动态曲线符合一级动力学方程,3种除草剂在土壤中的半衰期分别为16.9、26.7 d和8.6 d,在牧草中的半衰期分别为18.2、1.8 d和12.0 d,2,4-滴二甲胺盐在土壤和牧草中均属于易降解除草剂,二氯吡啶酸在土壤和牧草中残留期相对较长,氨氯吡啶酸在土壤中残留期相对长,而在牧草中则属于易降解除草剂。参照3种除草剂在牧草中的残留量和相应除草剂在矮生浆果、蔬菜、小麦、大麦、燕麦和油菜籽中的国内外最大残留限量标准评价,在天然草原喷施2,4-滴二甲胺盐+氨氯·二氯防除草原毒草,施药后30~45 d二氯吡啶酸在牧草中的残留量为4.1~2.3 mg/kg,氨氯吡啶酸在0.5 mg/kg以下,2,4-滴二甲胺盐在0.56 mg/kg以下,此期放牧,对牛、羊等家畜安全。 展开更多
关键词 二氯吡啶酸 氨氯吡啶酸 2 4-滴二甲胺盐 消解动态 土壤 牧草
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高纯度2-(4-氨基苯基)-1H-苯并咪唑-5-胺的合成 被引量:1
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作者 金宁人 刘琛 +2 位作者 肖庆军 施云龙 倪哲明 《化工进展》 EI CAS CSCD 北大核心 2009年第5期847-851,863,共6页
以廉价的2,4-二硝基苯胺(DNBA)和对硝基苯甲酰氯(NBC)为原料,通过缩合、还原和环合反应制备了2-(4-氨基苯基)-1H-苯并咪唑-5-胺(ABIA)。研究结果表明:170~180℃下的熔融缩合是制备三硝基中间体N-(4'-硝基苯甲酰基)-2,4-二硝基苯胺(... 以廉价的2,4-二硝基苯胺(DNBA)和对硝基苯甲酰氯(NBC)为原料,通过缩合、还原和环合反应制备了2-(4-氨基苯基)-1H-苯并咪唑-5-胺(ABIA)。研究结果表明:170~180℃下的熔融缩合是制备三硝基中间体N-(4'-硝基苯甲酰基)-2,4-二硝基苯胺(NDBA)的优选工艺,提纯后可获得纯度97%以上的NDBA,收率68.40%;NDBA在HCl-H2O溶液中先Pd/C催化加氢还原成N-(4'-氨基苯甲酰基)-2,4-二氨基苯胺(ADBA),再碱性环合反应,经乙醇-H2O重结晶后获得纯度99.5%以上的聚合级单体,收率为64.87%;经FT-IR、1H-NMR和13C-NMR定性为ABIA,以NBC计聚合级ABIA的总收率为44.37%。 展开更多
关键词 2-(4-氨基苯基)-1H-苯并咪唑-5-胺 N-(4'-氨基苯甲酰基)-2 4-二氨基苯胺 N-(4'-硝基苯甲酰基)-2 4-二硝基苯胺 2 4-二硝基苯胺 熔融缩合
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γ-Fe_(2)O_(3)/ZnO@CNTs催化光耦合臭氧降解水体中2,4-二氯苯酚
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作者 曹玲 贾子钰 +2 位作者 杨誉名 孙威 杨春维 《复合材料学报》 北大核心 2025年第8期4518-4525,共8页
内分泌干扰物2,4-二氯苯酚(DCP)化学结构较稳定,传统水处理技术降解效率不高。光耦合臭氧高级氧化技术(PCO)具有高效快速处理水中有机污染物的能力,可能成为DCP有效处理技术之一。本文将γ-Fe_(2)O_(3)与ZnO结合共负载于碳纳米管(CNTs)... 内分泌干扰物2,4-二氯苯酚(DCP)化学结构较稳定,传统水处理技术降解效率不高。光耦合臭氧高级氧化技术(PCO)具有高效快速处理水中有机污染物的能力,可能成为DCP有效处理技术之一。本文将γ-Fe_(2)O_(3)与ZnO结合共负载于碳纳米管(CNTs)之上,开发出γ-Fe_(2)O_(3)/ZnO@CNTs催化剂用于催化PCO降解水中DCP。结果表明:该催化剂可以有效促进DCP的降解,当DCP初始浓度为20 mg/L,O_(3)投加量为72 mg/(L·h)^(-1),催化剂投加量为1 g/L,模拟太阳光光源功率密度为5000 W/cm^(2)时,反应90 min DCP去除率可达98.9%,降解过程遵循准一级动力学规律。研究还探究了DCP降解路径,并确定了羟基自由基(·OH)、电子空穴(h^(+))和超氧自由基(·O_(2)^(−))是主要氧化基团。本文为DCP及其他难降解有机污染物的有效处理提供了一种新的处理方案。 展开更多
关键词 γ-Fe_(2)O_(3) ZNO 催化剂 光催化耦合臭氧催化 降解 2 4-二氯苯酚 自由基
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2,4-表油菜素内酯对镉胁迫下胡萝卜幼苗生理特性的影响
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作者 周志国 樊双虎 +1 位作者 邓晨 冯雪 《生物技术通报》 北大核心 2025年第5期165-174,共10页
【目的】分析不同浓度的2,4-表油菜素内酯(2,4-EBR)对镉胁迫下胡萝卜幼苗的生长特性、生理指标及镉吸收转运相关基因表达的影响,为胡萝卜对镉抗性的相关研究提供理论支撑。【方法】以胡萝卜‘红芯四号’为试验材料,采用实验室水培的方法... 【目的】分析不同浓度的2,4-表油菜素内酯(2,4-EBR)对镉胁迫下胡萝卜幼苗的生长特性、生理指标及镉吸收转运相关基因表达的影响,为胡萝卜对镉抗性的相关研究提供理论支撑。【方法】以胡萝卜‘红芯四号’为试验材料,采用实验室水培的方法,研究不同浓度(0.1、0.5、1和1.5μmol/L)2,4-EBR对CdCl2胁迫下胡萝卜幼苗生长特性、光合作用、抗氧化酶活性以及镉吸收转运相关基因表达的影响。【结果】胡萝卜幼苗在0.1mmol/L镉胁迫条件下生长受到显著抑制,外源施加1μmol/L2,4-EBR可以抑制镉离子的吸收和转运,促进胡萝卜幼苗根长和株高的增加,提高叶片SOD、POD、CAT和APX的活性,增加光合色素含量并提高叶片光合效率,抑制镉吸收转运相关基因DcHMA3、DcHMA4、DcCAX2、DcCAX4的表达,维持植物体氧化还原代谢途径平衡。【结论】2,4-EBR可促进胡萝卜根茎生长,增强抗氧化酶活性,提高光合效率,调节GSH-PCs代谢途径以及调控相关基因表达量,从而缓解胡萝卜幼苗在镉胁迫下的伤害,而且最适宜的2,4-EBR处理浓度为1μmol/L。 展开更多
关键词 镉胁迫 2 4-表油菜素内酯 胡萝卜 生长和生理特性 基因表达
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气相色谱-负化学源质谱法对水中2-甲-4-氯和2,4-滴的测定 被引量:17
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作者 匡科 赵建亮 +3 位作者 应光国 袁永钦 杨小兵 李忠军 《分析测试学报》 CAS CSCD 北大核心 2008年第8期816-819,824,共5页
建立了气相色谱-负化学源质谱法(GC-NCI MS)测定水中2-甲-4-氯(MCPA)和2,4-滴(2,4-D)2种酸性除草剂的分析方法。水样经过Oasis HLB柱萃取后,进行五氟苄基溴(PFBBr)衍生化,用2,4-二氯苯乙酸(2,4-DCPA)作内标进行定量分... 建立了气相色谱-负化学源质谱法(GC-NCI MS)测定水中2-甲-4-氯(MCPA)和2,4-滴(2,4-D)2种酸性除草剂的分析方法。水样经过Oasis HLB柱萃取后,进行五氟苄基溴(PFBBr)衍生化,用2,4-二氯苯乙酸(2,4-DCPA)作内标进行定量分析,并以2-甲4-氯丙酸(mecoprop)作回收率指示物对整个分析过程进行监控,以保证分析结果的准确性。mecoprop、MCPA和2,4-D在5、100、200ng/L3个不同添加水平下的回收率在82%~135%范围内,RSD在1.3%~9.3%范围内,在1~200μg/L线性范围内,相关系数r大于0.997,MCPA、2,4-D的方法检出限分别为0.60、0.45ng/L。2007年11月采用GC-NCI MS方法对南方地区某河流中的MCPA和2,4-D含量进行调查,其质量浓度分别不大于19.4ng/L和6.2ng/L,监测结果表明,该河流水质没有受到MCPA和2,4-D酸性除草剂的污染。 展开更多
关键词 气相色谱-负化学源质谱法 2-甲4-氯 2 4-滴 五氟苄基溴 2 4-二氯苯乙酸 2-甲4-氯丙酸
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高温胁迫下2,4-表油菜素内酯和丛枝菌根真菌对四季杜鹃光合特性及激素代谢的影响
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作者 郭嘉 熊定伟 +1 位作者 杨丽娟 程建军 《河南农业科学》 北大核心 2025年第10期110-120,共11页
为探究高温胁迫下叶际施用2,4-表油菜素内酯(EBR)、接种丛枝菌根真菌(AMF)地表多样孢囊霉(Diversispora epigaea)及其复合处理对四季杜鹃耐热性的影响机制,以四季杜鹃(Rhododendron hybridum)云栖烟霞扦插苗为试验材料,采用室内盆栽试验... 为探究高温胁迫下叶际施用2,4-表油菜素内酯(EBR)、接种丛枝菌根真菌(AMF)地表多样孢囊霉(Diversispora epigaea)及其复合处理对四季杜鹃耐热性的影响机制,以四季杜鹃(Rhododendron hybridum)云栖烟霞扦插苗为试验材料,采用室内盆栽试验,研究对照(CK,正常温度,不添加AMF、EBR)、单独高温(HS)、HS+AMF、HS+EBR、HS+EBR+AMF处理对四季杜鹃光合色素含量、气体交换参数、叶绿素荧光参数以及激素含量的影响。结果表明,高温胁迫抑制四季杜鹃生长,外观表型上表现为叶片黄化变小,大部分叶片枯死。叶片喷施EBR可以促进AMF侵染率、丛枝着生率以及泡囊数的增加,但对侵入位点数无显著影响。与HS处理相比,HS+EBR+AMF处理下四季杜鹃叶绿素a、叶绿素b、总叶绿素和类胡萝卜素含量分别增加84.3%、182.3%、105.8%和150.6%,净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)和瞬时水分利用效率(WUE)提高129.5%、78.9%、32.7%和28.1%,胞间CO_(2)浓度(Ci)下降11.7%;同时,HS+EBR+AMF处理增加了四季杜鹃叶片中PSⅡ最大光化学量子效率(Fv/Fm)、PSⅡ潜在活性(Fv/Fo)以及光化学猝灭系数(qP),降低了非光化学猝灭系数(NPQ),对四季杜鹃叶片中单位反应中心用于电子传递的能量(E_(ETo/RC))、单位面积吸收的光能(E_(ABS/CSm))、捕获的光能(E_(TRo/CSm))、电子传递的量子产额(E_(ETo/CSm))具有促进作用。高温胁迫下,四季杜鹃叶片中玉米素(ZT)、赤霉素(GA_(3))、生长素(IAA)含量降低,而脱落酸(ABA)含量增加,HS+EBR+AMF处理后ZT、GA_(3)、IAA含量分别增加54.2%、43.2%和29.5%,ABA含量下降26.5%。综上,EBR可以促进AMF对植物的侵染,相较于单一AMF或者EBR处理,二者复合处理下增强四季杜鹃耐热性的效果最好。 展开更多
关键词 四季杜鹃 高温 2 4-表油菜素内酯 丛枝菌根真菌 叶绿素 激素代谢 光合作用
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麦草畏和2,4-滴二甲胺盐在天然草原土壤和牧草中的消解动态研究
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作者 王玉灵 牛树君 +3 位作者 赵峰 余海涛 张新瑞 胡冠芳 《寒旱农业科学》 2025年第9期866-872,共7页
除草剂混用组合麦草畏+2,4-滴二甲胺盐能有效防除天然草原优势毒草黄帚橐吾等,施用除草剂后的安全放牧时间对确保家畜安全至关重要。为确定施用除草剂后的安全放牧时间和制定农药最大残留限量标准提供参考,利用超高效液相色谱串联质谱... 除草剂混用组合麦草畏+2,4-滴二甲胺盐能有效防除天然草原优势毒草黄帚橐吾等,施用除草剂后的安全放牧时间对确保家畜安全至关重要。为确定施用除草剂后的安全放牧时间和制定农药最大残留限量标准提供参考,利用超高效液相色谱串联质谱检测方法,对甘肃碌曲天然草原土壤和牧草中480 g/L麦草畏水剂和55%2,4-滴二甲胺盐水剂的残留消解动态进行了研究。结果表明,480 g/L麦草畏水剂和55%2,4-滴二甲胺盐水剂在天然草原土壤和牧草中的残留消解动态曲线均符合一级动力学方程,在土壤中的半衰期分别为1.8、4.7 d,在牧草中的半衰期分别为6.5、13.6 d。且480 g/L麦草畏水剂较55%2,4-滴二甲胺盐水剂更易在土壤和牧草中快速消解,但二者均属于易降解除草剂。依据这2种除草剂在牧草中的残留量和国内外最大残留限量标准进行评价,认为在天然草原喷施除草剂组合480 g/L麦草畏水剂+55%2,4-滴二甲胺盐水剂防除草原优势毒草黄帚橐吾等时,在施药后30~45 d放牧,对牛、羊等家畜安全。 展开更多
关键词 麦草畏 2 4-滴二甲胺盐 天然草原 土壤 牧草 消解动态
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层状半导体氧化物Li_(2)MnO_(3)制备及光催化降解2,4-DCP研究
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作者 周颖 赖寒 +4 位作者 代朋 彭秦磊 郭熙川 杨顶峰 李园园 《无机盐工业》 北大核心 2025年第10期139-146,共8页
通过固相合成法制备了层状Li_(2)MnO_(3),并将其应用于光催化降解水中的2,4-二氯苯酚(2,4-DCP)。利用X射线衍射仪(XRD)、透射电子显微镜(TEM)、傅里叶变换红外光谱(FT-IR)表征了光催化剂的形貌与结构,利用紫外-可见漫反射光谱(UV-Vis D... 通过固相合成法制备了层状Li_(2)MnO_(3),并将其应用于光催化降解水中的2,4-二氯苯酚(2,4-DCP)。利用X射线衍射仪(XRD)、透射电子显微镜(TEM)、傅里叶变换红外光谱(FT-IR)表征了光催化剂的形貌与结构,利用紫外-可见漫反射光谱(UV-Vis DRS)和电化学阻抗谱(EIS)分析了光催化剂的光学和电化学性质。研究发现,在900℃烧结温度下合成的Li_(2)MnO_(3)样品(LMO-900)展现出优异的光催化性能,30 min内对2,4-DCP的降解率约为87%。紫外-可见漫反射光谱(UV-Vis DRS)和莫特肖特基曲线(Mott-Schottky)表明,Li_(2)MnO_(3)的带隙为2.07 eV,价带电位为1.68 V(vs.NHE),导带电位为-0.39 V(vs.NHE),表明其具有良好的光生电子与空穴还原氧化能力。电化学阻抗谱(EIS)揭示了烧结温度对载流子分离效率的影响,其中LMO-900具有最高的载流子分离效率。自由基捕获实验表明,空穴(h^(+))和超氧阴离子自由基(·O_(2)~-)是Li_(2)MnO_(3)光催化降解2,4-DCP过程中的主要活性物种。电子结构计算分析表明,Mn—O键是光催化活性中心的关键,对2,4-DCP的降解起着决定性作用。 展开更多
关键词 层状氧化物 Li_(2)MnO_(3) 光催化 2 4-二氯苯酚
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氯代烃2,4-DCP的光催化降解与机制分析
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作者 赖寒 周颖 +4 位作者 樊昊 杨华夏 高蕾 李小宁 郭熙川 《化学工程》 北大核心 2025年第5期11-17,共7页
为了探究不同烧结温度和时间对Li_(2)TiO_(3)光催化性能的影响,利用高温固相法合成在不同烧结条件下的Li_(2)TiO_(3)样品,并通过XRD(X射线衍射)、SEM(扫描电子显微镜)、UV-Vis(紫外-可见漫反射)、EIS(阻抗)及MS(莫特-肖特基)曲线等手段... 为了探究不同烧结温度和时间对Li_(2)TiO_(3)光催化性能的影响,利用高温固相法合成在不同烧结条件下的Li_(2)TiO_(3)样品,并通过XRD(X射线衍射)、SEM(扫描电子显微镜)、UV-Vis(紫外-可见漫反射)、EIS(阻抗)及MS(莫特-肖特基)曲线等手段进行表征。选取2,4-DCP(2,4-二氯苯酚)作为目标污染物,探究催化剂在光催化降解中的性能。结果表明:烧结温度和烧结时间会影响催化剂的催化性能,其中900℃烧结10 h的Li_(2)TiO_(3)(LTO-900)在20 min对2,4-DCP的降解效果最佳,降解率为100%。阻抗图结果显示,温度会影响载流子的分离效率,LTO-900样品具有较高的载流子分离效率。自由基捕获实验表明,空穴和超氧阴离子自由基是2,4-DCP降解过程中主要的活性自由基。电子局域函数、原子投影能带图及原子投影态密度图进一步揭示,光催化反应的活性中心与氧原子的2p轨道及Ti—O键紧密相关。 展开更多
关键词 光催化 氯代烃 2 4-二氯苯酚 Li_(2)TiO_(3) 理论计算
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气相色谱-电子捕获检测器法同时测定土壤中2,4-二硝基甲苯、2,4,6-三硝基甲苯和黑索金的含量
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作者 秦容 邹家素 +2 位作者 赵红静 邹志芬 钟声 《理化检验(化学分册)》 北大核心 2025年第11期1293-1299,共7页
为实现土壤中2,4-二硝基甲苯、2,4,6-三硝基甲苯、黑索金的同时、快速、准确测定,进行了题示研究。采集土壤样品,于-50℃、真空压力9 Pa下冷冻干燥约40 h。取20 g样品,混匀后采用萃取溶剂体积比1∶1的丙酮-正己烷混合溶液在萃取温度100... 为实现土壤中2,4-二硝基甲苯、2,4,6-三硝基甲苯、黑索金的同时、快速、准确测定,进行了题示研究。采集土壤样品,于-50℃、真空压力9 Pa下冷冻干燥约40 h。取20 g样品,混匀后采用萃取溶剂体积比1∶1的丙酮-正己烷混合溶液在萃取温度100℃、氮气吹扫时间20 s的条件下进行加压流体萃取。于40℃将萃取液浓缩至约1 mL,过活化好的硅酸镁小柱,收集流出液,常压氮吹浓缩至约0.5 mL后用体积比1∶1的丙酮-正己烷混合溶液定容至1.0 mL。所得溶液进入气相色谱仪,在DB-5和DB-17色谱柱上以程序升温条件分离目标物,电子捕获检测器检测。结果显示:3种目标物的质量浓度均在一定范围内和峰面积呈线性关系,检出限(3.143 s)分别为2,1,2μg·kg-1;按照标准加入法进行回收试验,回收率为71.6%~118%,测定值的相对标准偏差(n=6)为1.6%~13%。 展开更多
关键词 气相色谱法 加压流体萃取法 土壤 2 4-二硝基甲苯 2 4 6-三硝基甲苯 黑索金
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