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1.
建立了测定2,4-二羟基二苯甲酮含量的分先先度法。实验表明,在pH为10的B—R缓冲溶液中,2,4-二羟基二苯甲酮在404nm波长下有最大吸收,8=4.36×10^4L/(m01.em).于1.0×10^-5mol/L~3.0×10^-4mol/L范围内其吸光度与浓度呈良好的线性关系,其线性回归方程为A=0.4361×10^4c(mol/L)+0.0083,相关系数为r=0.9996.用加入回收法进行试验,回收率为98.1%~104.7%.  相似文献   

2.
基于中性介质中,2,4-二氯苯酚对鲁米诺-铁氰化钾化学发光体系有明显的增敏作用,提出了流动注射化学发光法测定痕量2,4-二氯苯酚的方法.在优化的试验条件下,2,4-二氯苯酚的化学发光强度与其浓度在1.0×10-7~1.0×10-5 mol/L范围内呈线性关系,方法的检出限(3S/N)为1.060×10-8 mol/L.对浓度为1.0×10-5mol/L2,4-二氯苯酚溶液连续测定11次,测定值的相对标准偏差为2.1%.取工业废水水样,经固相萃取后用该法测定其中痕量2,4-二氯苯酚含量,同行业推荐标准方法对比,结果相近.  相似文献   

3.
报道了一种绿色、简易的合成甲苯-2,4-二氨基甲酸甲酯的方法.以廉价易得的非金属硒作催化剂,CO作羰基化试剂,通过硒催化2,4-二氨基甲苯和甲醇在一氧化碳和氧气存在下经“一锅法”的氧化羰基化反应来直接合成目标产物甲基-2,4-二氨基甲酸甲酯.并提出了硒催化羰基化合成甲苯-2,4-二氨基甲酸甲酯的机理.  相似文献   

4.
以2-氯吡啶为原料,经过取代反应、威廉森反应、劳森反应和缩合反应合成了5-{4-[2-(甲基-2-吡啶氨基)-乙氧基]-亚苄基}-4-硫代-2,4-噻唑烷二酮,4步反应的收率分别为65.49%、63.68%、68.83%和85.48%.中间体和目标化合物经MS、IR和1H-NMR确证是预期的化合物.  相似文献   

5.
生物淋洗法修复2,4-DNT-3-SA污染土壤   总被引:1,自引:0,他引:1  
采用静态生物淋洗法处理含2,4-二硝基甲苯-3-磺酸钠(2,4-DNT-3-SA)的土壤。考察供氧条件、土水比及温度对2,4-DNT-3-SA去除效果的影响,结果表明,在好氧、37oC、土水比为10:5的条件下,2,4-DNT-3-SA去除率最高,达到98.75%。采用高通量测序法分析土壤中微生物菌落结构及多样性,结果表明,土壤中的优势菌属主要为假单胞菌属、鞘脂菌属和芽孢乳杆菌属。  相似文献   

6.
用2,4-二羟基苯乙酮和氨基硫脲为原料,在微波辅助作用下固相合成了2,4-二羟基苯乙酮缩氨基硫脲,利用红外光谱及单晶X射线法对目标化合物进行了表征,该化合物为单斜晶系,空间群为C2/c,晶体学参数n=2.0900(2)nm,b=0.79290(8)nm,c=1.32481(14)nm;β=100.2090(10)°;F(000)=944,Z=8,V=2·1607(4)nm3,Dc=1.365g·cm^-3,Mr=225.27,最终结构偏离因子R=0.0460,Rw=0.1309,S=1.031,最终差值电子密度的最大值和最小值分别为401nm^-3。和-247nm^-3.  相似文献   

7.
A strong hydrogen-bond acidic (HBA) polymer linear fluoroalcoholic polysiloxane (PLF), synthesized by one-step hydrosilylation, was introduced for 2,4-dinitrotoluene (2,4-DNT) detection using surface acoustic wave (SAW) devices. FT-IR spectra and 1H NMR spectra char- acterizations confirmed its molecular structure. Then, PLF was dissolved in chloroform, and spray coated onto a 434 MHz SAW device. And subsequently, the sensitivity and selectivity of the fabricated sensor were studied based on a SAW test platform. To 2,4-DNT of 1 ppm and 100 ppb (for DNT, 1 ppm = 8.1 mg/m3; 1 ppb = 8.1 ;tg/m3), the responses of the sensor rose 7.7 and 1.5 kHz, respectively. Furthermore, compared with some common interference vapors at 10 mg/m3, the response of the sensor to 2,4-DNT at 1 ppm was 5 times stronger. The sensitive property was attributed to the hydrogen bond interaction between the hexafluoroisopropanol (HFIP) group in PLF and the basic lone electron pairs of nitro-groups in 2,4-DNT. Comparison between the PLF sensor and hydroxyl group functionalized polymer (carbowax and MOBCD)-coated sensors was investigated, and the results showed that the PLF sensor exhibited better sensitivity. In a word, the PLF sensor exhibited fast response, negligible baseline drifts and excellent reversibility, indicating good candidates of HFIP group functionalized HBA polymers for practical nitroaromatic explosives detection.  相似文献   

8.
Nanoscale iron was detected by TEM, X-ray diffraction and X-ray photoelectron spectroscopy. It was found that the size of the nanoscale iron particles is in the range of 30–40 nm according to TEM image, and it contains abundant Fe3O4 as passivating layers on the surface of the core-shell structure. To improve its performance, dilute HCl was used for the removal of the passivating layers, and the degradation of 2,4-dichlorophenol (2,4-DCP) was measured for the nanoscale iron samples treated and untreated. Experimental results demonstrated that the removal of 2,4-DCP by untreated nanoscale iron is mainly due to the adsorption of 2, 4-DCP by nanoscale iron, and there are no degradation products detected by HPLC in the process. However, excellent dechlorination of 2,4-DCP was gained by HCl-treated nanoscale iron, and 2-chlorophenol, 4-chlorophenol and phenol were detected during the process. It was concluded that dechlorination is the key reaction pathway for the degradation of 2,4-DCP by activated nanoscale iron, and phenol is found to be the main product.  相似文献   

9.
提出了邻氯苯酚与2,4_二氯苯酚混合体系非线性吸光度表示式.非线性吸光度由2组分各自对吸光度的贡献和由于混合而导致的2组分各自贡献的改变以及交互作用项3部分构成.依据该式,利用非线性Kalman滤波法处理了42组邻氯苯酚与2,4_二氯苯酚的标准混合溶液在260~300nm区间的紫外光谱数据,在混酚的标准溶液中酚的质量浓度均在0.1~15mg/L范围内.利用偏最小二乘法,将其制作成扩展Kalman滤波标准工作系数矩阵.通过对非线性吸光度关系式Taylor级数展开进行线性化处理,得到其向量函数的Jacobi矩阵,从而完成了非线性Kalman滤波器的设置.回收实验显示,扩展Kalman滤波同时测量邻氯苯酚与2,4-二氯苯酚双组分体系是准确、稳定的.  相似文献   

10.
研究了Yb(OTF),催化剂对2,4-二氨基甲苯(TDA)与碳酸二甲酯甲氧羰基化反应合成2,4-甲苯二氨基甲酸甲酯(TDC)的催化活性,考察了反应温度和反应时间对Yb(OTF),催化活性的影响。在该催化剂的作用下,反应温度453K,反应时间5h时TDA转化率可达100%,TDC的产率达到23、6%,同时考察了Yb(OTF)3催化剂的寿命,经4次重复使用催化剂基本不失活。Ln(OTF)3(Ln=La,Nd,Yb)催化活性的比较表明催化剂Lewis酸性的强弱与TDC的产率成正比。  相似文献   

11.
在优化条件下,用NaH、n-BuLi、THF、芴、溴、二溴代烃、二酮为原料,通过溴代反应合成了新型的含芴发光材料前体9-(2,7-二溴-9-正丁基-9-H-芴)壬烷-2,4-二酮(DBBFOD);产物的收率为56%,纯度>99%,其结构经1H NMR、13C NMR、MS和元素分析确证.  相似文献   

12.
含β-D-糖苷的5-氟尿嘧啶类抗肿瘤药物的合成   总被引:2,自引:0,他引:2  
以糖为原料,经过乙酰化、溴化得到溴代糖.以所得的溴代糖与5-氟尿嘧啶-1-基-乙酸及N^1-(2-呋喃烷基)-5-氟尿嘧啶通过酯化、N-烷基化反应,合成了8个新型含糖苷的5-氟尿嘧啶类衍生物,采用IR、MS和^1H NMR表征了目标化合物的结构.  相似文献   

13.
建立了一个基于磁性荧光双探针基础上的免疫快速检测体系,以实现液相中快速检测食品中2,4-二氯苯氧乙酸(2,4-D)残留.该体系将2,4-D抗体结合Fe3O4@SiO2-NH2得到的复合物作为磁性探针和固相载体,2,4-D-OVA被标记CdTe@SiO2-NH2作为荧光探针以产生荧光信号,通过荧光探针与磁性探针复合物与2,4-D抗体竞争结合实现免疫快速检测.探讨了荧光探针最佳优化条件,在p H值8.2,2,4-D-OVA加入量为500μL,偶联时间为70 min时,偶联得到的荧光信号最强,双探针检测后得到该检测体系最低检测限为3.55×10-8.得到金磁、量子点荧光双探针免疫系统,绘出标准曲线,得到最低检测限达3.55×10-8.该检测体系与传统ELISA方法相比,可以大大缩短检测时间,放大检测信号.  相似文献   

14.
小鼠实验性接触性皮炎模型制作方法探讨   总被引:8,自引:0,他引:8  
目的探讨ICR小鼠实验性接触性皮炎模型制作方法。方法用不同浓度的2,4_二硝氯苯、在不同时间内对ICR小鼠皮肤进行致敏和激发实验,对皮损组织病理、皮损严重度和皮炎持续时间进行对比观察。结果第2组、4组组织病理与典型的接触性皮炎病理相符,其中第2组在最后一次激发后皮肤炎症持续时间较长。结论2组采用的方法为ICR小鼠实验性接触性皮炎模型的较理想制作方法。  相似文献   

15.
首先, 以微孔结构的ZSM-5沸石为前驱物, 经碱液处理不同时间后与介孔模板剂十六烷基三甲基溴化铵(CTAB)混合, 水热处理后制备微孔-介孔ZSM-5分子筛, 并用X射线衍射(XRD)、 Fourier变换红外光谱(FT-IR)、 N2吸附 脱附和透射电镜(TEM)等方法表征微孔-介孔ZSM-5分子筛的理化性质. 其次, 将微孔 介孔ZSM-5分子筛作为苯酚叔丁醇烷基化反应的催化剂, 利用苯酚转化率与2,4-二叔丁基苯酚的选择性测试所得材料的催化性能. 结果表明: [JP2]碱处理1 h可获得微孔和介孔复合较好的ZSM-5, 且该催化剂具有较好的苯酚叔丁基化催化性能, 苯酚的转化率最高为86.2%, 大分子2,4 二叔丁基苯酚的选择性可达57.9%.  相似文献   

16.
采用液相还原法制备了纳米Fe/Ni双金属材料,分析了其催化降解2,4-二氯酚的机理、降解过程中Ni的作用及相关参数变化。结果表明,2,4-二氯酚被纳米Fe/Ni降解的主要途径是2,4-二氯酚直接被脱去2个氯原子生成苯酚,此外也可先脱去一个氯原子生成2-氯酚或4-氯酚,然后继续脱氯生成苯酚;纳米Ni可将纳米Fe腐蚀产生的氢气转化为活性氢原子,活性氢原子再对2,4-二氯酚进行脱氯降解。在反应初期,溶液氧化还原电位及溶解氧浓度快速降低,pH及溶解铁浓度急剧升高,随着反应的进行,上述各参数值趋于稳定。  相似文献   

17.
The conditions of color reaction of Aluminium(III) with a new organic reagent 2,3,7-trihydroxy-9-[2,4-dihydroxy)phenylazo] phenylfluorone (ARPF) in the presence of cetyltrimethyammonium bromide (CTMAB) were studied. It was found that Aluminium(III) reacts with ARPF and CTMAB in pH 6.5 HAc-NaAc buffer solution to form a 1∶2 red complex with maximum absorption at 562 nm. The molar absorptivity is 1.10×105 L·mol−1·cm−1. Beer’s law is obeyed in the range of 0–5.5 μg Al(III) per 25 mL. The method has been applied to determination of Aluminium in the limestone with satisfactory results. To whom Correspondence should be addressed Foundation item: Supported by Special Funds of State Education Committee for Doctorate Research Biography: Huang Ying-ping (1963-), male, Ph.D Candidate.  相似文献   

18.
Metal nanoparticles are effective for remediation of contamination with a range of compounds including chlorinated organics.However,the sorption process of the passivation oxide layers on the metal nanoparticle surfaces may result in incomplete degradation of contaminants.This phenomenon can be prevented by an acidic washing procedure or reaction in an acidic medium.In this paper,nickel nanoparticles manufactured via the carbonyl powder process were analyzed using scanning electron microscopy,transmission electron microscopy,X-ray diffraction and energy-dispersive X-ray spectroscopy.The sorption and degradation of 2,4-dichlorophenol (2,4-DCP) by nickel nanoparticles under acidic conditions was then investigated.Transmission electron microscopy and XRD results showed that the nickel nanoparticles range in size from 10 to 20 nm,and a thin passivation layer of NiO is present on the surface.This oxide layer can be removed by pretreatment washing with acidic solutions.It was indicated that dechlorination was the key reaction pathway for degradation of 2,4-DCP by nickel nanoparticles under acidic conditions.The main degradation products were 4-Chlorophenol,2-Chlorophenol,and Phenol,and among these,Phenol was dominant.The acidic medium promoted degradation by providing an appropriate pH,and H+ may be involved in the reaction.Dechlorination of 2,4-DCP by nickel nanoparticles under the acidic condition follows the second order kinetic model,and the rate constants at 298,306,316 K are 0.02,0.2 and 0.3 (g L h)-1,respectively.  相似文献   

19.
研究了龙山荞、浦江荞、美国荞和牡丹荞四种甜荞子叶和下胚轴的愈伤组织形成与分化的影响因子.结果表明:17.8μmol/L~26.6μmol/L(4.0 mg/L~6.0 mg/L)的BA与0.9μmol/L(0.2 mg/L)的2,4-D配合使用可有效促进甜荞愈伤组织中芽的分化和芽的生长;高浓度的蔗糖(4.5%~6.0%)促进甜荞愈伤组织根的分化和愈伤组织的生长;在培养基中附加活性炭抑制甜荞愈伤组织分化根.  相似文献   

20.
用2,4-二硝基氟苯与各种取代的苯肼在DMSO中通过亲核取代反应合成了一系列氢化偶氮苯类化合物,其中8个是未见报道的新化合物,反应条件温和,反应时间短,后处理简便,收率93%~98%.  相似文献   

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