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81.
巯基乙酸自组装膜DNA电化学传感器对转基因NOS的定量检测 总被引:5,自引:1,他引:5
以转基因植物中常用的根癌农杆菌终止子(NOS)为检测对象, 将巯基乙酸自组装于金电极表面形成巯基乙酸自组装单分子膜, 再利用乙基-(3-二甲基氨丙基)碳二亚胺盐酸盐(EDC)和N-羟基琥珀酰亚胺(NHS)的活化作用将NOS探针ssDNA序列固定于金电极表面形成NOS电化学生物传感器, 以亚甲基蓝(MB)为杂交指示剂, 对NOS靶基因相关序列进行了定量检测. 相似文献
82.
Synthesis and properties of liquid crystalline polyurethanes 总被引:1,自引:0,他引:1
1,4-Bis(p-hydroxybenzoate)phenylene was prepared using 1,4-bis(trimethylsiloxy)benzene and p-hydroxybenzoyl chloride as starting materials. A series of novel 1,4-bis(p-hydroxyalkoxybenzoate)phenylene were synthesized by reaction of 1,4-bis(p-hydroxybenzoate) phenylene with 3-brompropanol and 4-bromobutanol, respectively. The liquid crystal polyurethanes were prepared
by 1,4-bis(p-hydroxyalkoxybenzoate)phenylene with MDI (p-methylene diphenylenediisocyanate) and 2,4-TDI(2,4-toluenediisocyanate), respectively. The thermotropic properties, the melting
point (T
m) and the isotropization temperature (T
i) of the synthesized polyurethanes were characterized by DSC, IR and POM. It showed that all of the polyurethane polymers
exhibited thermotropic liquid crystalline properties between 144°C and 260°C. The transition temperature (T
m and T
i) decreased with an increase in the length of the methylene spacer.
__________
Translated from Journal of Qingdao University of Science and Technology, 2006, 27(1) (in Chinese) 相似文献
83.
Electrochemical studies on the interaction of heparin with crystal violet and its analytical application 总被引:1,自引:0,他引:1
In this paper, crystal violet (CV) was used to determine heparin concentration by linear sweep voltammetry on a dropping mercury
electrode (DME). In Britton-Robinson (B-R) buffer solution, pH 3.0, CV had a well-defined second-order derivative linear sweep
voltammetric reductive wave at −0.74 V (vs. SCE). After the addition of heparin to the CV solution, the reductive peak current
decreased greatly with the positive movement of the peak potential and without appearance of new peaks in the scanning potential
range. Based on the decrease in the reductive peak current, a new voltammetric method for the determination of heparin was
established. The conditions for the interaction and the electrochemical detection were optimized, and interfering substances
were investigated. Under the optimal conditions, the decrease in reductive peak currents of CV was proportional to heparin
concentration in the range 0.1–8.0 mg/L with the linear regression equation Δip″(nA) = 400.42 + 1563.11c (mg/L), (n = 14, γ = 0.993). The detection limit was 0.092 mg/L. This new method was further successfully applied to the determination of heparin
content in heparin sodium injection samples with satisfactory results. The binding ratio and binding mechanism were also studied
by the electrochemical method.
The text was submitted by the authors in English. 相似文献
84.
85.
Multi-dimple phenomena in TEHL point contacts 总被引:3,自引:0,他引:3
Theoretical analysis and experimental measurement of the multiple dimples in thermal elastohydrodynamic lubrication (TEHL) point contacts have been carried out. Good agreement is found between the theoretical and experimental results. A thermal multi-spike theory is proposed to explain the multi-dimple phenomena. 相似文献
86.
《Radiation Physics and Chemistry》2007,76(8-9):1308-1311
In this work, blends of a difunctional epoxy monomer and a thermoplastic toughening agent are E-beam irradiated at two different dose rates and two different total absorbed doses. The influence of the processing conditions on the thermal properties and on the morphology of the obtained matrices has been investigated. In particular, it is shown how the increase of the dose rate causes an increase of the temperature during irradiation, thus inducing a simultaneous thermal and radiation curing. On the contrary, at low-dose rate the system mainly undergoes to radiation curing, thus making the cured material very sensible to a post-irradiation thermal treatment with a significant improvement of the thermal properties. 相似文献
87.
88.
《中国化学快报》2020,31(5):1281-1287
Extensive structure-activity relationships (SARs) study of JND3229 was conducted to yield a series of new reversible 2-oxo-3,4-dihydropyrimido[4,5-d]pyrimidine privileged scaffold as EGFRC797S inhibitors. One of the most potent compound 6i potently suppressed EGFRL858R/T790M/C797S kinase with an IC50 value of 3.1 nmol/L, and inhibited the proliferation of BaF3 cells harboring EGFRL858R/T790M/C797S and EGFR19D/T790M/C797S mutants with IC50 values of 290 nmol/L and 316 nmol/L, respectively. Further, 6i dose-dependently induced suppression of the phosphorylation of EGFRL858R/T790M/C797S and EGFR19D/T790M/C797S in BaF3 cells. Compound 6i may serve as a promising lead compound for further drug discovery overcoming the acquired resistance of non-small cell lung cancer (NSCLC) patients. 相似文献
89.
《Tetrahedron: Asymmetry》2006,17(2):287-291
Racemic α′-acetoxy α,β-unsaturated cyclopentanone and cyclohexanone have been resolved into the corresponding enantiomerically enriched α′-hydroxylated and acetoxylated compounds with 96–97% ee via PLE hydrolysis. Stereoselectivity in the palladium(II)-catalyzed reaction between the enantiomerically enriched α′-acetoxylated compounds and diazomethane has been investigated. In the α′-acetoxylated cyclopentenone, preferential cyclopropanation occurs in the anti-form, whereas α′-acetoxylated cyclohexenone affords both syn- and anti-products (syn:anti, 61:36%). The relative configuration of the products was determined by NOE experiments. 相似文献
90.
CHU Yongbao GAO Baoyu YUE Qinyan WANG Yan & WANG Shuguang . School of Environmental Science Engineering Shandong University Jinan China . College of Material Environment Qingdao University of Science Technology Qingdao China 《中国科学B辑(英文版)》2006,(4)
Polyaluminum chloride (PAC) coagulant has been developed and widely used in water and wastewater treatment industry since the 1980s[1]. PAC is normally made by partial hydrolysis of acid aluminum chloride solution using slow alkaline titration method. However, this method would result in many different Al species. Among these Al species, it seems that tridecamer (Al13O4(OH) 724 , often denoted by Al13) is the most effective and stable polymeric Al species for water and wastewater treatme… 相似文献