检索结果-南通市图书馆

A pulsed switching peroxi-coagulation process to control hydroxyl radical production and to enhance 2,4-dichlorophenoxyacetic acid degradation

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2018年第5期12卷 86-90页

作者： Yaobin Lu Songli He Dantong Wang Siyuan Luo Aiping Liu Haiping Luo Guangli Liu Renduo Zhang Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology School of Environmental Science and EngineeringSun Yat-sen UniversityGuangzhou 510006China Zhaoqing Environmental Monitoring Station Zhaoqing Institute of Environmental ScienceZhaoqing 526040China Nanjing Institute of Environmental Sciences Ministry of Environmental ProtectionNanjing 210042China

The aim of this study was to develop a new pulsed switching peroxi-coagulation system to control hydroxyl radical(∙OH)production and to enhance 2,4-dichlorophenoxyacetic acid(2,4-D)*** system was constructed with a sacrifice iron anode,a Pt anode,and a gas diffusion *** of H_(2)O_(2) and Fe^(2+)was controlled separately by time delayers with different pulsed switching *** current densities of 5.0 mA/cm^(2)(H_(2)O_(2))and 0.5 mA/cm^(2)(Fe^(2+)),the∙OH production was optimized with the pulsed switching frequency of 1.0 s(H_(2)O_(2)):0.3 s(Fe^(2+))and the ratio of H_(2)O_(2) to Fe^(2+)molar concentrations of *** the optimal condition,2,4-D with an initial concentration of 500 mg/L was completely removed in the system within 240 *** energy consumption for the 2,4-D removal in the system was much lower than that in the electro-Fenton process(686 vs.13610 kWh/kg TOC).The iron consumption in the system was~20 times as low as that in the peroxi-coagulation process(19620 vs.3940400 mg/L)within 240 *** system should be a promising peroxi-coagulation method for organic pollutants removal in wastewater.

关键词： Pulsed switching peroxi-coagulation system Energy consumption Hydroxyl radical production 2,4-dichlorophenoxyacetic acid

Selective removal of 2,4-dichlorophenoxyacetic acid from water by molecularly-imprinted amino-functionalized silica gel sorbent

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2010年第2期22卷 237-241页

作者： Deman Han ,Wenping Jia,Huading Liang Department of Chemistry,Taizhou University,Linhai 317000,China. Department of Chemistry Taizhou University Linhai 317000 China

A molecularly-imprinted amino-functionalized sorbent for selective removal of 2,4-dichlorophenoxyacetic acid （2,4-D） was prepared by a surface imprinting technique in combination with a sol-gel process. The 2,4-D-imprinted amino-functionalized silica sorbent was characterized by FT-IR, nitrogen adsorption and static adsorption experiments. The selectivity of the sorbent was investigated by a batch competitive binding experiment using an aqueous 2,4-D and 2,4-dichlorophenol （2,4-DCP） mixture or using an aqueous 2,4-D and 2,4- dichlorophenylacetic acid （DPAC） mixture. The largest selectivity coefficient for 2,4-D in the presence of 2,4-DCP was found to be over 18, the largest relative selectivity coefficient between 2,4-D and 2,4-DCP over 9. The static uptake capacity and selectivity coefficient of the 2,4-D-imprinted functionalized sorbent are higher than those of the non-imprinted sorbent. The imprinted functionalized silica gel sorbent offered a fast kinetics for the extraction/stripping of 2,4-D, 73% of binding capacity （200 mg/L 2,4-D onto 20 mg of imprinted sorbent） was obtained within 5 min and the adsorbed 2,4-D can be easily stripped by the mixture solution of ethanol and 6 mol/L HC1 （V：V =1：1）. In a test of five extraction/stripping cycles, the adsorption capacity of the sorbent was all above 93% of that of the fresh sorbent. Experimental result showed the potential of molecularly-imprinted amino-functionalized sorbent for selective removal of 2,4-D.

关键词： 2,4-dichlorophenoxyacetic acid molecular imprinting functionalized silica gel

Synthesis,Structural,Spectroscopic Characterization and Biological Properties of the Zn(Ⅱ),Cu(Ⅱ),Ni(Ⅱ),Co(Ⅱ),and Mn(Ⅱ)Complexes With the Widely Used Herbicide 2,4-dichlorophenoxyacetic acid

在线全文

学校读者我要写书评

暂无评论

光谱学与光谱分析 2021年第6期41卷 1982-1987页

作者： Lamia A.Albedair Department of Chemistry College of SciencePrincess Nourah Bint Abdulrahman UniversityRiyadh 11671Saudi Arabia

2,4-dichlorophenoxyacetic acid(2,4-D)is a board-leaf selective herbicide and globally used in agricultural *** mode,spectroscopic investigations and biological properties of complexes formed between 2,4-D(C_(6)H_(3)Cl_(2)OCH_(2)·COOH;HL)with Zn(Ⅱ),Cu(Ⅱ),Ni(Ⅱ),Co(Ⅱ),and Mn(Ⅱ)metal ions were *** characterize the binding mode between 2,4-D and the metal ions,many physicochemical approaches were *** complexes obtained are characterized quantitatively and qualitatively by using micro elemental analysis,FTIR spectroscopy,UV-Vis spectroscopy,1H-NMR,and magnetic susceptibility *** of these approaches suggested that the gross formula of the complexes obtained with the metal ions were[ZnL_(2)](2H_(2)O(1),[CuL_(2)(H_(2)O)_(2)](2),[NiL_(2)](3H_(2)O(3),[CoL_(2)(H_(2)O)_(2)](4),and[MnL_(2)(H_(2)O)_(2)](5).In all complexes,two L-anion were coordinated the metal ion by their bidentate carboxylate *** the spectral study,all the complexes obtained as monomeric structure and the metals center moieties are six-coordinated with octahedral geometry except Ni(Ⅱ)and Zn(Ⅱ)complexes which existed as a tetrahedral and square pyramidal geometry *** complexes were screened in vitro against several microbes(fungi and bacteria)using Kirby-Bauer disc diffusion method,and data has demonstrated that complex 3 showed excellent antifungal activity.

关键词： 2,4-dichlorophenoxyacetic acid Complexes Spectroscopy FTIR Antimicrobial screening

Proline and Glutamine Improve in vitro Callus Induction and Subsequent Shooting in Rice

在线全文

学校读者我要写书评

暂无评论

Rice science 2015年第6期22卷 283-289页

作者： Bhausaheb PAWAR Prashant KALE Jyoti BAHURUPE Ashok JADHAV Anil KALE Sharad PAWAR State Level Biotechnology Centre Mahatma Phule Agricultural University

This study was conducted to evaluate the effects of proline and glutamine on in vitro callus induction and subsequent regeneration and to develop a reproducible and highly efficient plant regeneration protocol in four rice genotypes, viz. Pawana, Jaya, Indrayani and Ambemohar. Considerable variation in response to plant growth regulators and amino acid supplements used was observed in all the four genotypes. Medium supplemented with proline and glutamine was shown to be superior to medium without proline and glutamine. The best callusing from mature embryo was observed on Murashige and Skoog （MS） medium supplemented with 2.0 mg/L 2,4-dichlorophenoxyacetic acid （2,4-D）, 500 mg/L proline and 500 mg/L glutamine. Shoot induction was higher in the callus obtained from medium supplemented with 500 mg/L proline and 500 mg/L glutamine. The highest shoot regeneration frequency （83.2%） was observed on MS medium with 2.0 mg/L benzylaminopurine, 0.5 mg/L 1-naphthaleneacetic acid, 500 mg/L proline, and 500 mg/L glutamine in the callus obtained from MS medium supplemented with 2.0 mg/L 2,4-D, 500 mg/L proline and 500 mg/L glutamine. Among the four genotypes, Pawana has the highest regeneration efficiency （83.2%）, whereas the regeneration efficiency of the rest three rice genotypes was in the range of 32.0% to 72.3%. This optimized regeneration protocol can be efficiently used for Agrobacterium mediated genetic transformation in rice.

关键词： callus induction glutamine proline rice Agrobacterium mediated genetic transformation 2,4-dichlorophenoxyacetic acid Murashige and Skoog medium

Photochemical degradation of typical halogenated herbicide 2,4-D in drinking water with UV/H_(2)O_(2)/micro-aeration

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2009年第12期52卷 2351-2357页

作者： CHU WenHai GAO NaiYun LI Chong CUI Jing State Key Laboratory of Pollution Control and Resources Reuse Tongji UniversityShanghai 200092China Department of Civil and Structure Engineering Hong Kong Polytechnic UniversityHong KongChina

UV/H2O2/micro-aeration is a newly developed process based on UV/H2O2. Halogenated pesticide 2,4-dichlorophenoxyacetic acid (2,4-D) photochemical degradation in aqueous solution was studied under various solution conditions. The UV intensity,initial 2,4-D concentrations and solution temperature varied from 183.6 to 1048.7 μW·cm-2,from 59.2 to 300.0 μg·L-1 and from 15 to 30℃,respectively. The concentration of hydrogen peroxide (H2O2) and pH ranged from 0 to 50 mg·L-1 and 5 to 9,and different water quality solutions (tap water,distilled water and deionized water) were examined in this study. With initial concentration of about 100 μg·L-1,more than 95.6% of 2,4-D can be removed in 90 min at intensity of UV radiation of 843.9 μW·cm-2,H2O2 dosage of 20 mg·L-1,pH 7 and room temperature. The removal efficiency of 2,4-D by UV/H2O2/micro-aeration process is better than UV/H2O2 process. The photodecomposition of 2,4-D in aqueous solution follows pseudo-first-order kinetics. 2,4-D is greatly affected by UV irradation intensity,H2O2 dosage,initial 2,4-D concentration and water quality solutions,but it appears to be slightly influenced by pH and temperature. There is a linear relationship between rate constant k and UV intensity and initial H2O2 concentration,which indicates that higher removal capacity can be achieved by the improvement of these factors. Finally,a preliminary cost analysis reveals that UV/H2O2/micro-aeration process is more cost-effective than the UV/H2O2 process in the removal of 2,4-D from drinking water.

关键词： 2,4-dichlorophenoxyacetic acid endocrine disrupting chemicals photochemistry advanced oxidation processes pollution control cost analysis

Qualitative and Quantitative Changes in Biochemical Constituents in the Rice Plant Treated with Different Xenobiotics

在线全文

学校读者我要写书评

暂无评论

Journal of Agricultural Science and Technology(B) 2013年第1期3卷 17-25页

作者： Mangalam Nantha kumar Vemuri Shashibhushan Vinnakota Jhansi Lakshmi Muthugonder Mohan Bellamkonda Ramesh Ainp on Pesticide Residues Acharya N. G.Ranga Agricultural University Hyderabad .4ndhra Pradesh 500030 India Directorate of Rice Research Hyderabad Andhra Pradesh 500030 lndia

Experiments were conducted at Entomology division of Directorate of Rice research to study the qualitative and quantitative changes in biochemical constituents in the rice plant treated with different xenobiotics, viz. insecticides like deltamethrin, imidacloprid, herbicide like 2,4-dichlorophenoxyacetic acid, fungicide like carbendazim, green manure Calotropis gigantea leaves, botanicals like Neem Seed Powder and fertilizer urea along with control plants of TN1, PTB33 and Swama varieties comprising of total 15 treatments. Application of butachlor, carbendazim, deltamethrin and excessive nitrogen fertilization resulted in increased population build up of brown plant hopper （BPH）. Significantly, lower honeydew excretion （13 mme area） in the BPH nymphs was observed on resistant PTB33 variety compared to susceptible TN1 and Swarna varieties （116 and 110 mm2 respectively）. In susceptible TN1 variety, the sucrose content was significantly higher （9.35 mg/g tissue） compared to BPH resistant PTB33 （5.32 mg/g tissue）. The BPH resistant PTB33 variety exhibited significantly lower free amino acid content （1.23 mg/g tissue） as compared to TN1 （2.51 mg/g）. The C/N ratio was comparatively high in the resistant PTB33 alone （4.32）, but was low in PTB33 applied with 2,4-D ＋ carbendazim （2.73）, 2,4-D ＋ imidacloprid ~ carbendazim （2.3）, excess urea fertilizer （2.18）. The total phenol contents measured in resistant PTB33 （7.5 mg/g dry wt）, susceptible TN1 （5.865 mg/g dry wt） and the popular variety Swarna （5.57 mg/g dry wt） were almost same and no statistical difference was observed. Further, treatment of these varieties with different xenobiotics and botanicals also did not significantly alter their total phenol content. However, the phenol content of the resistant PTB 33 alone and treated with xenobiotics was higher compared to the susceptible TN 1 and Swarna varieties alone and treated with xenobiotics. The plant biochemical constituents such as free amino acids, sucrose were lower

关键词： 2,4-dichlorophenoxyacetic acid Oryza sativa L. xenobiotics BPH.