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1.
建立了HPLC分析聚合酶链反应(PCR)产物的方法,探讨了梯度、流速、柱温等条件对相对分子质量参照物λ-DNA-HindⅢ分离的影响,NaCl以40~50mmol/min的梯度变化,流速为1mL/min时分离效果最佳。该法精密度和回收率高、线性良好,可用于PCR扩增条件优化时的相对定量分析。  相似文献   

2.
邓凡政  石影 《分析化学》1998,26(9):1115-1117
在pH4.0~6.0的HAc-NaAc缓冲溶液中,Co(Ⅱ),Fe(Ⅲ),Ni(Ⅱ),Cu(Ⅱ)等金属离子与亚硝基R盐可形成稳定络合物,加入HCl适当提高溶液酸度(HCl浓度在0.3~0.6mol/L)用聚乙二醇2000(PEG)-硫酸铵-亚硝基R盐体系萃取,Co(Ⅱ)可被PEG相几乎完全萃取,而Fe(Ⅲ),Ni(Ⅱ),Cu(Ⅱ)基本上不被萃取,实现了Co(Ⅱ),Fe(Ⅲ),Ni(Ⅱ),Cu(Ⅱ)  相似文献   

3.
利用高效DEAE离子交换液相色谱法分离纯化了绿脓杆菌标准菌株PAO1外膜蛋白。流动相为pH8.0Tris-HCl缓冲液,色谱柱为TSKgel-DEAE-5PW(0.75cm×7.5cmi.d.)。通过纯化外膜蛋白,可以为研究绿脓杆菌外膜通透性与抗生素耐药性之间的关系及缩短研究周期提供有效的方法。  相似文献   

4.
EDTA金属螯合物阴离子交换色谱行为研究   总被引:1,自引:0,他引:1  
本文报道Zn(Ⅱ)、Cr(Ⅲ)、Fe(Ⅲ)等金属-EDTA螯合物的阴离子交换色谱行为.采用PRP-100阴离子色谱柱,以2.0mL/min.流速、4mmol/L苯甲酸为淋洗液,电导检测器检测,可以很好地分离Zn-EDTA2-、Cr-EDTA-、Fe-EDTA-.方法可用于废水中金属离子的检测.  相似文献   

5.
廖杰  赵玉兰  董芳霆  杨军  郝秀华 《色谱》1999,17(5):491-492
建立了分离逆转录聚合酶链反应(RT PCR)产物的高效液相色谱方法,反应液直接进样,用TSKgelDEAE NPR柱分离,Tris HCl缓冲溶液(pH90) 氯化钠线性梯度洗脱,于260nm处检测。用所建立的方法分析了大鼠肠缺血/再灌注损伤后外周血中性粒细胞(PMN)磷脂酶A2mRNA的表达。  相似文献   

6.
左联  周建忠  姚天爵 《色谱》1999,17(1):46-48
 利用高效DEAE离子交换液相色谱法分离纯化了绿脓杆菌标准菌株PAO1外膜蛋白。流动相为pH8.0Tris-HCl缓冲液,色谱柱为TSKgel-DEAE-5PW(0.75cm×7.5cmi.d.)。通过纯化外膜蛋白,可以为研究绿脓杆菌外膜通透性与抗生素耐药性之间的关系及缩短研究周期提供有效的方法。  相似文献   

7.
研究了脱氧核糖核酸的极谱伏安行为,在0.1mol.L^-1NH4Cl溶液中DNA产生一良好的极谱峰,峰电位Ep=-1.65V(vs.Ag/AgCl),且峰电流ip与DNA的浓度在4.5*10^-5-3.7*10^-4mol.LO^-1范围内呈线性关系,可望用于DNA的定量分析。  相似文献   

8.
双金属杂原子分子筛CrCoBEA的合成、波谱及催化性能研究   总被引:4,自引:0,他引:4  
采用水热晶化法首次合成出BEA结构含铬、钴,双金属杂原子分子筛CrCoBEA,对晶化时间,晶化温度,成胶配比等合成条件进行了优化研究,采用XRD,FTIR,UV-VisDRS,ESR及催化反应等方法测试其物相、波谱性质和催化性能,结果表明物质的量比为TEOS:0.017「Cr(acac)3」:0.017「Co(acac)3」:(0.58-0.64)TEAOH:0.01Al(NO3)3:(16-20  相似文献   

9.
PMBP为载体的乳状液膜提取钪的研究   总被引:4,自引:0,他引:4  
研究了以1-苯基-3-甲基-4-苯甲酰基吡唑酮-5(PMBP)为流动载体的乳状液膜(ELM)法提取钪,确定最佳液膜体系组成为0.4%PMBP-3%Span80-5%液体石蜡-煤油-3mol/LHCl,Roi=1:1(油内比).Rwe(水乳比)可达20:1.用该体系对钪与混合稀土进行分离,钪的回收率可达95.5%,分离系数β(SC/RE)=32.0。  相似文献   

10.
本文研究了铕(Ⅲ)在乙二酸双(α─氨基乙基)醚四乙酸(简称GBETA)-NaCl介质中的极谱行为及测定最佳条件,GBETA浓度为0.01mol/L,NaCl浓度为0.4mol/L,通N2除O25min。最低检出限为4.2×10-7mol/L,测定了发光材料BaFCl(Eu)中Eu(Ⅱ)的含量。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

14.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

15.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

16.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

17.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

18.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

19.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

20.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

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