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Novel Zwitterionic Surfactants: Synthesis and Surface Active Properties of N-(3-Alkoxy-2-Hydroxypropyl)-N, N-Dimethyl glycine Betaines 被引量:1
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作者 Jing Qu GUAN Xi You LI Chen Ho TUNG (Institute of Photographic Chemistry. Chinese Academy of Sciences. Beijing 100101) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第6期499-502,共4页
Five new zwitterionic surfactants with long chain alkyl betaine structure incorporated with hydroxylpropyl group have been synthesized. Their structures were identified by elemental analysis, IR (HNMR)-H-1, and (CNMR)... Five new zwitterionic surfactants with long chain alkyl betaine structure incorporated with hydroxylpropyl group have been synthesized. Their structures were identified by elemental analysis, IR (HNMR)-H-1, and (CNMR)-C-13. Surface tension experiments showed that these surfactants have higher surface activity than those without hydroxypropyl group. The values of CMC and gamma(CMC) of these surfactants have been determined. 展开更多
关键词 ppm Synthesis and Surface Active Properties of N Novel Zwitterionic Surfactants OH OCH n-dimethyl glycine Betaines Alkoxy-2-Hydroxypropyl
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ELECTROCHEMICAL AND SPECTROELECTROCHEMICAL CHARACTERIZATION OF p-TRICYANOETHENYL-N,N-DIMETHYL ANILINE
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《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第4期305-306,共2页
The redox behaviours of a donor-acceptor model compound. p-tricyano-ethenyl-N, N-dimethyl aniline was investigated by electrochemical and spectroelectrochemical methods. The results indicate that charge transfer betwe... The redox behaviours of a donor-acceptor model compound. p-tricyano-ethenyl-N, N-dimethyl aniline was investigated by electrochemical and spectroelectrochemical methods. The results indicate that charge transfer between the donor(amino) and the acceptor(cyanoethenyl) groups takes place in the process of oxidation of this compound. 展开更多
关键词 SCE ELECTROCHEMICAL AND SPECTROELECTROCHEMICAL CHARACTERIZATION OF p-TRICYANOETHENYL-N n-dimethyl ANILINE Chen
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Synthesis, Crystal Structure and Biological Activities of 3-Bromo-5-(4-chlorophenyl)-4-cyanopyrrole-N,N-dimethyl-2-carboxamide
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作者 许庆博 华云涛 +3 位作者 唐强 周宝晗 陈坤 徐保明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第5期747-752,共6页
The title compound 3-bromo-5-(4-chlorophenyl)-4-cyanopyrrole-N,N-dimethyl-2-amide(3) was synthesized with 4-bromo-2-(4-chlorophenyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile(1) and N,N-dimethylformamide... The title compound 3-bromo-5-(4-chlorophenyl)-4-cyanopyrrole-N,N-dimethyl-2-amide(3) was synthesized with 4-bromo-2-(4-chlorophenyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile(1) and N,N-dimethylformamide(2) by the α-C acylation reaction catalyzed by potassium t-butoxide, and characterized by IR, 1H-NMR and X-ray single-crystal diffraction. It crystallizes in monoclinic, space group P2(1/n)with a = 12.789(2), b = 13.783(2), c = 17.980(3) °, β = 109.230(3)°, V = 2992.5 A3, Mr = 352.62, Dc = 1.565 mg/m3, Z = 8, m = 2.924 mm-1, F(000) = 1408, the final R = 0.0424 and w R = 0.0973 for 3518 observed reflections with I 〉 2σ(I). A total of 23559 reflections were collected, of which 6242 were independent(Rint = 0.0566). The insecticidal, herbicidal and antibacterial activities of compound 3 were determined, and the experimental results showed that the mortality of 3 at the concentration of 100 ppm on the Fipronil against Linnaeus was 76.6%, the growth inhibition rate of 3 against Cynodon Dactylon under the condition of 100 ppm was 35.8% and the inhibitory activity of 3 at the concentration of 25 ppm against Fusarium graminearum reached 50.9%. Hence, the title compound has the value of further research and application prospect. 展开更多
关键词 3-bromo-5-(4-chlorophenyl)-4-cyanopyrrole-N n-dimethyl-2-amide SYNTHESIS crystal structure biological activity
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Synthesis,Crystal Structure and Photoluminescence Property of Ag(I)with N,N-dimethyl-4-(pyridine-4-yldiazenyl)aniline
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作者 徐凌云 梅啸 闫春辉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第3期355-360,共6页
A 2D plane coordination compound [Ag_2(Dpya)_2.(NO_3)_2]n was synthesized and characterized by FT-IR,elemental analysis and TG analysis.The red crystal was obtained via solvent diffusion method at room temperature... A 2D plane coordination compound [Ag_2(Dpya)_2.(NO_3)_2]n was synthesized and characterized by FT-IR,elemental analysis and TG analysis.The red crystal was obtained via solvent diffusion method at room temperature and is slightly soluble in organic solvents.Its structure was determined by single-crystal X-ray diffraction analysis.It crystallizes in monoclinic,space group P1 with a = 10.7995(13),b = 7.4748(8),c = 18.364(2) A,β = 98.916(4)o,V = 1464.5(3) A^3,Z = 2,C_(26)H_(28)Ag_2N_(10)O_6,M_r = 792.32,Dc = 1.302 Mg/m^3,F(000) = 792,μ(Mo Ka) = 1.356 mm^-1,R = 0.0575 and w R = 0.0826.The compound [Ag_2(Dpya)_2.(NO_3)_2]_n is a two-dimensional structure and there are two kinds of coordination configurations about the Ag atoms in the compound.The Ag(1) center is tetrahedrally coordinated with two O atoms of NO_3^-and two N atoms from the ligand Dpya.Meanwhile,the Ag(2) is five-coordinated by five O atoms from three NO_3^-anions.The Ag centers(Ag(1) and Ag(2)) connect to themselves as well as with each other by the bridging NO_3^-anions.And the coordination compound shows photoluminescence with an emission peak at 530 nm(λex = 450 nm) as the ligand Dpya. 展开更多
关键词 N n-dimethyl-4-(pyridine-4-yldiazenyl) aniline Ag compound X-ray diffraction structure photoluminescence
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Gaseous products of aqueous N,N-dimethyl hydroxylamine degraded by radiation
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作者 WANG Jinhua LI Chun +5 位作者 WU Minghong XU Gang BAO Borong ZHENG Weifang HE Hui ZHANG Shengdong 《Nuclear Science and Techniques》 SCIE CAS CSCD 2010年第4期233-236,共4页
In this work,the 0.1-0.5 mol·L-1 N,N-dimethylhydroxylamine(DMHA) were irradiated to 5-25 kGy,and gaseous products of mainly hydrogen,methane,ethane and n-butane were measured by gas chromatography.The results sho... In this work,the 0.1-0.5 mol·L-1 N,N-dimethylhydroxylamine(DMHA) were irradiated to 5-25 kGy,and gaseous products of mainly hydrogen,methane,ethane and n-butane were measured by gas chromatography.The results show that the volume fraction of hydrogen and methane increases with the concentration of DMHA and dose,and the latter does not change markedly at high doses. 展开更多
关键词 二甲基 气态产物 辐射降解 羟胺 气相色谱法 丁烷气体 体积分数
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Solvent extraction of U(Ⅵ) by N,N-dimethyl-N',N'-dioctylsuccinylamide and N,N-dimethyl-N',N'-didecylsuccinylamide in cyclohexane
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作者 Yu Cui Xiao-Feng Yang +3 位作者 Cheng Yang Ye-Xin Li Guo-Zhu Chen Guo-Xin Sun 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第3期68-73,共6页
The extraction of uranyl nitrate by novel extractants of N,N-dimethyl-N',N'-dioctylsuccinylamide(DMDOSA)and N,N-dimethyl-N',N'-didecylsuccinylamide(DMDDSA) from aqueous nitric/nitrate solutions was inv... The extraction of uranyl nitrate by novel extractants of N,N-dimethyl-N',N'-dioctylsuccinylamide(DMDOSA)and N,N-dimethyl-N',N'-didecylsuccinylamide(DMDDSA) from aqueous nitric/nitrate solutions was investigated.It was found both the concentration of HNO_3 and extractants had an effect on the U(Ⅵ) extraction distribution.The extraction mechanism was established,and stoichiometry of the main extracted species was confirmed to be UO_2(NO_3)_2·2DMDOSA and UO_2(NO_3)_2·2DMDDSA,respectively.Both of the extraction reactions are exothermic.FTIR spectral study of the U(Ⅵ) extracted species was also made. 展开更多
关键词 溶剂萃取 二甲基 环己烷 FTIR光谱 硝酸铀酰 化学计量比 O3浓度 萃取反应
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Qualitative and quantitative analysis of hydrogen and carbon monoxide produced by radiation degradation of N, N-dimethyl hydroxylamine
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作者 WANGJinhua BAOBorong +4 位作者 WUMinghong SUNXilian ZHANGXianye HUJingxin YEGuoan 《辐射研究与辐射工艺学报》 CAS CSCD 北大核心 2005年第2期110-110,共1页
关键词 辐射衰退 一氧化碳 气相色谱 二甲基羟胺
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Catalytic wet oxidation of N,N-dimethyl formamide over ruthenium supported on CeO_2 and Ce_(0.7)Zr_(0.3)O_2 catalysts 被引量:3
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作者 Jiawen Gong Dongzhi Li +4 位作者 Li Wang Wangcheng Zhan Yanglong Guo Yunsong Wang Yun Guo 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第3期265-272,共8页
A series of Ru supported on CeO_2 and Ce_(0.7)Zr_(0.3)O_2(CeZrO) was prepared by incipient-wet impregnation method and investigated in the catalytic wet oxidation of N,N-dimethyl formamide(DMF) in batch reactor. The p... A series of Ru supported on CeO_2 and Ce_(0.7)Zr_(0.3)O_2(CeZrO) was prepared by incipient-wet impregnation method and investigated in the catalytic wet oxidation of N,N-dimethyl formamide(DMF) in batch reactor. The physicochemical property of the catalysts was characterized by Brunauer-Emmett-Teller(BET), X-ray diffraction(XRD), H_2 temperature-programmed reduction(H_2-TPR), X-ray photoelectron spectroscopy(XPS) and thermogravimetry(TG). Compared with 3%Ru/CeO_2, 3%Ru/Ce_(0.7)Zr_(0.3)O_2 catalyst exhibits much higher performance for DMF degradation due to the promotion of Ru dispersion and the transfer of active oxygen, and 99% DMF conversion and 97% COD elimination are obtained at 453 K,2.5 MPa oxygen pressure after 5 h. The reaction mechanism of DMF degradation was suggested. The carbonaceous species deposition and oxidation of Ru can be responsible for catalyst deactivation. And the catalyst activity can be recovered by air calcination and H_2 reduction. 展开更多
关键词 Catalytic wet oxidation N n-dimethyl FORMAMIDE Ru Degradation Catalyst DEACTIVATION and regeneration Rare earths
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Theoretical study on the hydrolysis mechanism of N,N-dimethyl-N′-(2′,3′-dideoxy-3′-thiacytidine)formamidine
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作者 ZHANG Chang1 & XUE Ying2? 1 College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, China 2 College of Chemistry, Sichuan University, Chengdu 610064, China 《Science China Chemistry》 SCIE EI CAS 2008年第10期911-917,共7页
The hydrolysis mechanisms of N,N-dimethyl-N′-(2′,3′-dideoxy-3′-thiacytidine)formamidine (FA-3TC) in the gas phase and in aqueous solution were studied by use of the density functional theory B3LYP/6-31+G(d, p) met... The hydrolysis mechanisms of N,N-dimethyl-N′-(2′,3′-dideoxy-3′-thiacytidine)formamidine (FA-3TC) in the gas phase and in aqueous solution were studied by use of the density functional theory B3LYP/6-31+G(d, p) method. Two possible reaction pathways in the title reaction were considered. In one pathway water attacks the C=N double bond first (path A) while in the other water attacks the C—N single bond first (path B). The calculated results indicate that the first step in both pathways is the rate-limiting process and path A is more favorable than path B in the gas phase. The effect of solvent water on the title reaction was assessed at the B3LYP/6-31+G(d, p) level of theory based on the po-larizable continuum model (CPCM). In water the first mechanism (path A) is also favored. 展开更多
关键词 N n-dimethyl-N′-(2′ 3′-dideoxy-3′-thiacytidine)formamidine hydrolysis solvent effect B3LYP polarizable continuum model
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The thermal decomposition of N,N-dimethyl-3-oxa-glutaramic acid and the kinetics of its second-stage thermal decomposition reaction
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作者 SUN DaZhi CHEN Jing 《Science China Chemistry》 SCIE EI CAS 2008年第11期1127-1131,共5页
N,N-dimethyl-3-oxa-glutaramic acid was purified and characterized by 1H-NMR, Fourier transform in-frared spectroscopy (FT-IR) and elemental analysis. The thermal decomposition of the title compound was studied by mean... N,N-dimethyl-3-oxa-glutaramic acid was purified and characterized by 1H-NMR, Fourier transform in-frared spectroscopy (FT-IR) and elemental analysis. The thermal decomposition of the title compound was studied by means of thermogravimetry differential thermogravimetry (TG-DTG) and FT-IR. The ki-netic parameters of its second-stage decomposition reaction were calculated and the decomposition mechanism was discussed. The kinetic model function in a differential form, apparent activation energy and pre-exponential constant of the reaction are 3/2 [(1-α) 1/3-1]-1, 203.75 kJ-mol-1 and 1017.95s-1, respec-tively. The values of ΔS≠, ΔH≠ andΔG≠ of the reaction are 94.28 J-mol-1-K-1, 203.75 kJ-mol-1 and 155.75 kJ-mol-1, respectively. 展开更多
关键词 decomposition N n-dimethyl-3-oxa-glutaramic acid KINETICS
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掺混含氧燃料对混合燃料喷射特性的影响研究
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作者 罗福强 伍子旭 +1 位作者 王楚翘 金天宇 《车用发动机》 北大核心 2024年第5期18-24,41,共8页
为探究添加含氧燃料对燃料喷射特性的影响,将体积分数均为50%的聚甲氧基二甲醚(PODE)和正丁醇掺混于柴油制得PODE-柴油混合燃料和正丁醇-柴油混合燃料,标记为P50和B50。在高压共轨试验台上使用基于冲量法的喷射特性测试系统,研究了柴油... 为探究添加含氧燃料对燃料喷射特性的影响,将体积分数均为50%的聚甲氧基二甲醚(PODE)和正丁醇掺混于柴油制得PODE-柴油混合燃料和正丁醇-柴油混合燃料,标记为P50和B50。在高压共轨试验台上使用基于冲量法的喷射特性测试系统,研究了柴油、PODE-柴油混合燃料、正丁醇-柴油混合燃料三种燃料在多种工况下的喷射特性差异。结果表明,掺混含氧燃料对喷油速率有较大的影响:P50的体积流量小于柴油,而质量流量则相反;B50和柴油的喷油速率在低压下差异很小,但当压力升高至130 MPa时,二者的喷油速率差异明显;相同脉宽及喷射压力时与柴油相比,循环喷油量以体积计,B50大于柴油且差距随压力上升而增大,而P50则低于柴油且差距随压力上升而缩小;循环喷油量以质量计,P50和B50均高于柴油且差异率随压力上升而增大,但B50和柴油差异率的上升幅度比P50小;以喷射能量计,除小脉宽工况外,B50和P50的喷射能量均小于柴油,喷射能量由大到小排序为柴油、B50、P50。 展开更多
关键词 混合燃料 喷射特性 冲量法 聚甲氧基二甲醚 正丁醇
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阳离子型聚N-羟甲基丙烯酰胺水凝胶的制备及其对废水中甲基橙的吸附性能研究
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作者 从金月 黄超群 +3 位作者 贾伟娜 刘冰 王璇 于良民 《现代化工》 CAS CSCD 北大核心 2024年第S01期257-263,共7页
采用水溶液聚合法制备了阳离子型聚N-羟甲基丙烯酰胺水凝胶(CPNMA),并对其吸附废水中甲基橙(MO)的性能进行探究。利用SEM、FT-IR、TG及XPS对CPNMA进行表征。通过吸附动力学和吸附等温线模型拟合发现,在25℃下CPNMA对MO的吸附行为更符合... 采用水溶液聚合法制备了阳离子型聚N-羟甲基丙烯酰胺水凝胶(CPNMA),并对其吸附废水中甲基橙(MO)的性能进行探究。利用SEM、FT-IR、TG及XPS对CPNMA进行表征。通过吸附动力学和吸附等温线模型拟合发现,在25℃下CPNMA对MO的吸附行为更符合拟二级动力学和Langmuir等温吸附模型,吸附平衡时间为960 min,理论最大吸附量为371.6 mg/g。分析了吸附温度和溶液pH对吸附效果的影响,结果表明,在吸附温度为35℃及溶液pH=6时CPNMA可以呈现出最佳的吸附效果。综合分析,CPNMA的吸附机理包括氢键、静电作用、范德华力、n-π相互作用、表面吸附和孔隙填充。 展开更多
关键词 N-羟甲基丙烯酰胺 二甲基二烯丙基氯化铵 水凝胶 甲基橙 吸附
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硝基取代的芳香卤代烃在低共熔溶剂中的二甲氨基化反应
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作者 王婕 李珍珍 +4 位作者 潘彤 饶立航 黄甲想 蒋琪 盛文兵 《湖南中医药大学学报》 CAS 2024年第7期1213-1218,共6页
目的利用卤代芳烃的亲核取代反应在芳环中引入二甲氨基,探讨反应条件对硝基取代的芳香卤代烃胺化反应的影响。方法以2-溴-1-氟-4-硝基苯作为模型探究最佳反应条件,并用不同位置、不同卤原子取代的硝基苯探究反应底物的范围。结果反应最... 目的利用卤代芳烃的亲核取代反应在芳环中引入二甲氨基,探讨反应条件对硝基取代的芳香卤代烃胺化反应的影响。方法以2-溴-1-氟-4-硝基苯作为模型探究最佳反应条件,并用不同位置、不同卤原子取代的硝基苯探究反应底物的范围。结果反应最佳反应条件为使用1.00 mL的N,N-二甲基甲酰胺(N,N-dimethylformamide,DMF)为胺化剂,1.5倍当量KOH提供碱性环境,5.00 mL的低共熔溶剂(deep eutectic solvents,DESs)(氯化胆碱∶甘油=1∶2)为溶剂,在80℃下反应24 h。在底物范围扩展中有效得到一系列4-二甲氨基硝基苯化合物及其衍生物,经1H-NMR、13C-NMR确证其结构。结论DMF在DESs中可以有效充当二甲氨基化试剂,DESs溶剂选择性提高硝基对位上的卤原子的亲核取代反应活性,且不活化邻位卤原子,在优化后的最佳条件下反应,最高产率可达84%。这种特殊的区域选择性是其他溶剂中不具备的优势,同时该方法具有绿色环保、简单方便、产率适中的特点。 展开更多
关键词 低共熔溶剂 亲核取代反应 区域选择 N N-二甲基-4-硝基苯胺 N N-二甲基甲酰胺
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掺混含氧燃料对柴油模型燃料燃烧过程的影响
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作者 李铭迪 李广华 +2 位作者 陈健 胡焰彬 李友势 《华南师范大学学报(自然科学版)》 CAS 北大核心 2024年第2期11-17,共7页
采用Chemkin-Pro柴油机燃烧模型,以正庚烷作为柴油的模型燃料,构建了乙醇/二甲醚/正庚烷燃烧机理。研究乙醇和二甲醚这两种含氧燃料的不同掺混比(摩尔比)对正庚烷燃烧温度、燃烧压力以及燃烧产物的影响规律。结果表明:与掺混二甲醚相比... 采用Chemkin-Pro柴油机燃烧模型,以正庚烷作为柴油的模型燃料,构建了乙醇/二甲醚/正庚烷燃烧机理。研究乙醇和二甲醚这两种含氧燃料的不同掺混比(摩尔比)对正庚烷燃烧温度、燃烧压力以及燃烧产物的影响规律。结果表明:与掺混二甲醚相比,掺混乙醇对反应温度和压力的降低更为显著。而当乙醇和二甲醚同时掺混时,二甲醚的掺混比成为决定反应时刻的关键因素。随着二甲醚掺混比从15%增加到35%,燃烧反应提前了约10°(曲轴转角)。此外,二甲醚掺混比对氧化自由基的生成时刻具有显著影响,掺混比越高,自由基的生成时刻越早。在自由基摩尔分数峰值方面,乙醇掺混比例发挥着主导作用。随着乙醇掺混比的增加,3种自由基的摩尔分数峰值均呈现上升趋势。在燃烧产物方面,掺混乙醇能够有效降低甲醛和乙醛的生成量,而掺混二甲醚则能够减少乙醛的生成,但可能导致甲醛生成量的增加。当乙醇和二甲醚同时掺混,并增加二甲醚的比例时,甲醛和乙醛的摩尔分数峰值均下降,同时CO_(2)的最终生成量也有所减少。 展开更多
关键词 乙醇 二甲醚 正庚烷 数值模拟
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(3R,4R)-N,4-二甲基-1-(苯基甲基)-3-哌啶胺盐酸盐的制备
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作者 陈德响 左慧 +1 位作者 倪亚平 马良秀 《山东化工》 CAS 2024年第12期26-28,34,共4页
以a-乙酰-γ-丁内酯为起始原料与碘甲烷反应合成化合物II;化合物II与氢溴酸反应水解溴代化合物III;化合物III再与溴素反应得到二溴代产物IV;化合物IV与苄胺关环得到化合物V;化合物V在转氨酶作用下,甲胺作为氨源,得到ee值99.5%以上的化合... 以a-乙酰-γ-丁内酯为起始原料与碘甲烷反应合成化合物II;化合物II与氢溴酸反应水解溴代化合物III;化合物III再与溴素反应得到二溴代产物IV;化合物IV与苄胺关环得到化合物V;化合物V在转氨酶作用下,甲胺作为氨源,得到ee值99.5%以上的化合物I。考察催化剂、酶催化剂、物质的量比、反应温度对反应的影响,考察氢溴酸、溴素的回收利用情况。结果表明:化合物II的最佳工艺条件为碳酸钠为催化剂,碘甲烷为甲基化试剂,化合物III的最佳工艺条件氢溴酸既做反应试剂同时也作为溶剂;化合物IV最佳工艺条件酸性条件下溴素溴代得到二溴产物;化合物V的最佳工艺条件是与苄胺直接反应得到产物;化合物I的最佳工艺条件是常温下酶转化得到手性产品。 展开更多
关键词 (3R 4R)-N 4-二甲基-1-(苯基甲基)-3-哌啶胺盐酸盐 托法替布 合成 酶催化
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QuEChERS-EMR-GC/MS测定鱼肉制品中N-二甲基亚硝胺含量的方法学研究
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作者 张洁 董榕贵 《贵州科学》 2024年第4期71-75,共5页
目的:建立一种QuEChERS-EMR结合气相色谱串联质谱技术快速分析鱼肉制品中N-二甲基亚硝胺的方法。方法:样品加入内标,采用乙腈提取,经QuEChERS-EMR净化,VF-WaxMS(60 m×0.25 mm×0.25μm)色谱柱分离,在单离子检测(SIM)扫描,内标... 目的:建立一种QuEChERS-EMR结合气相色谱串联质谱技术快速分析鱼肉制品中N-二甲基亚硝胺的方法。方法:样品加入内标,采用乙腈提取,经QuEChERS-EMR净化,VF-WaxMS(60 m×0.25 mm×0.25μm)色谱柱分离,在单离子检测(SIM)扫描,内标法定量。结果:N-二甲基亚硝胺在2.0~50.0 ng/mL浓度范围内线性关系良好,相关系数r为0.9994,方法检出限为1.0μg/kg,方法定量限为3.3μg/kg,添加浓度水平分别为4.0μg/kg、20μg/kg、40μg/kg时,测定回收率在83.1%~104.3%之间,相对标准偏差在3.3%~6.1%之间。鱼肉基质对N-二甲基亚硝胺的基质效应为7.5%,表现为弱基质效应,可以忽略。结论:该方法操作简便,经济高效,环保,准确度高和重复性好,以及基质效应弱,适用于鱼肉制品中N-二甲基亚硝胺的测定。 展开更多
关键词 QuEChERS-EMR N-二甲基亚硝胺 鱼肉制品 气相色谱串联质谱
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动物性水产干制品中N -二甲基亚硝胺的防控
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作者 胡胜群 苏瑶瑶 +1 位作者 章智 曾为永 《农产品加工》 2024年第19期111-113,共3页
列举了近些年部分动物性水产干制品中N-二甲基亚硝胺检测不合格信息和处罚信息,介绍N-二甲基亚硝胺的安全风险及化学特性。就如何防控该指标限量方面,围绕加强原料控制、生产过程控制、N-二甲基亚硝胺前体物控制、加强生产人员管理知识... 列举了近些年部分动物性水产干制品中N-二甲基亚硝胺检测不合格信息和处罚信息,介绍N-二甲基亚硝胺的安全风险及化学特性。就如何防控该指标限量方面,围绕加强原料控制、生产过程控制、N-二甲基亚硝胺前体物控制、加强生产人员管理知识培训等方面提出个人见解,并建议生产经营企业建立健全食品质量安全管理体系,根据企业实际制定N-二甲基亚硝胺防控规范,以开展动态防控。 展开更多
关键词 水产干制品 N-二甲基亚硝胺 防控
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双烷链阳离子表面活性剂的合成与定量分析 被引量:33
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作者 施云海 陈啟斌 +2 位作者 童思 刘洪来 胡英 《分析化学》 SCIE EI CAS CSCD 北大核心 2003年第3期322-325,共4页
以N ,N 二甲基烷基叔胺和α,ω 二溴烷烃为原料 ,无水乙醇为溶剂合成阳离子型Gemini表面活性剂。反应产物以混合溶剂乙酸乙酯 乙醇重结晶纯化后 ,用红外光谱和核磁共振进行结构分析 ;以溴酚蓝为指示剂、二氯乙烷为分散相的两相化学滴定... 以N ,N 二甲基烷基叔胺和α,ω 二溴烷烃为原料 ,无水乙醇为溶剂合成阳离子型Gemini表面活性剂。反应产物以混合溶剂乙酸乙酯 乙醇重结晶纯化后 ,用红外光谱和核磁共振进行结构分析 ;以溴酚蓝为指示剂、二氯乙烷为分散相的两相化学滴定法测定其含量。结果表明 :7种已合成的阳离子型Gemini的活性物含量均在 97.5 展开更多
关键词 合成 定量分析 双烷链阳离子表面活性剂 亲核加成 成盐反应 化学滴定分析 二甲基烷基叔胺 二溴烷烃 GEMINI
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N,N-二甲基甲酰胺的生产与应用 被引量:61
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作者 刘兴泉 唐毅 +2 位作者 戴汉松 李淑华 何妮珍 《化工科技》 CAS 2002年第1期46-49,共4页
综述了N ,N 二甲基甲酰胺 (DMF)的生产工艺及其在国内外的应用领域 ,并对国内市场需要作出了简要的分析。指出了N ,N 二甲基甲酰胺的广阔发展前景。建议生产厂家采用一步法生产 ,以降低成本 ,提高产品质量 ,从而提高其市场竞争力。
关键词 N N-二甲基甲酰胺 DMF 生产工艺 应用 合成 酯化法 羰化法
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单甲脒农药的微生物降解代谢研究 被引量:31
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作者 王保军 刘志培 杨惠芳 《环境科学学报》 CAS CSSCI CSCD 北大核心 1998年第3期296-302,共7页
研究了门多萨假单胞菌DR8(PseudomonasmendocinaDR8)菌株对单甲脒农药的降解代谢.该菌利用单甲脒作为生长的唯一氮源.其对单甲脒的呼吸作用试验确证了该农药的生物可降解性.单甲脒对细菌生物氧化代... 研究了门多萨假单胞菌DR8(PseudomonasmendocinaDR8)菌株对单甲脒农药的降解代谢.该菌利用单甲脒作为生长的唯一氮源.其对单甲脒的呼吸作用试验确证了该农药的生物可降解性.单甲脒对细菌生物氧化代谢关联酶活性的影响研究表明,脱氢酶对单甲脒较敏感,而NADH氧化酶则耐受性较强.单甲脒生物降解特性研究表明,DR8菌株的单甲脒降解酶为组成酶,主要分布于细胞壁和细胞膜组分,该酶作用于单甲脒的Km值约为514mmol/L.经紫外吸收光谱和薄层层析等分析检测,单甲脒降解过程中形成氨和2,4二甲基苯胺.该菌对于单甲脒农药的降解属于共代谢作用. 展开更多
关键词 单甲脒 微生物降解 降解 代谢作用 农药
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