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1.
In this paper we determine the projective unitary representations of finite dimensional Lie supergroups whose underlying Lie superalgebra is , where is a compact simple Lie superalgebra and A is a supercommutative associative (super)algebra; the crucial case is when is a Graßmann algebra. Since we are interested in projective representations, the first step consists in determining the cocycles defining the corresponding central extensions. Our second main result asserts that, if is a simple compact Lie superalgebra with , then each (projective) unitary representation of factors through a (projective) unitary representation of itself, and these are known by Jakobsen's classification. If , then we likewise reduce the classification problem to semidirect products of compact Lie groups K with a Clifford–Lie supergroup which has been studied by Carmeli, Cassinelli, Toigo and Varadarajan. 相似文献
2.
Considering an inhomogeneous brane embedded in a five dimensional constant curvature bulk, we find the non-static and spherically symmetric exact solutions of the Einstein equations on the brane. With different choices of the parameters, one interesting case/solution is studied. We show that an inhomogeneous brane model can explain the accelerated expansion of the universe at large distance scales and also the galaxy rotation curves of spiral galaxies without assuming the existence of dark matter or new modified theories at the galactic scales. 相似文献
3.
The domino Knoevenagel hetero-Diels-Alder reaction of the O-propargylated salicylaldehydes and 4-hydroxycoumarin leads to pyrano[2,3-c]coumarins 3 and pyrano[2,3-c]chromones 4 in high yield in the presence of CuI as a Lewis acid. In all cases, the reaction was shown to exhibit high regioselectivity and form product 3 as main product. 相似文献
4.
Nanomolar Determination of Methyldopa in the Presence of Large Amounts of Hydrochlorothiazide Using a Carbon Paste Electrode Modified with Graphene Oxide Nanosheets and 3‐(4′‐Amino‐3′‐hydroxy‐biphenyl‐4‐yl)‐acrylic Acid 下载免费PDF全文
A novel electrochemical sensor for sensitive detection of methyldopa at physiological pH was developed by the bulk modification of carbon paste electrode (CPE) with graphene oxide nanosheets and 3‐(4′‐amino‐3′‐hydroxy‐biphenyl‐4‐yl)‐acrylic acid (3,′AA). Applying square wave voltammetry (SWV), in phosphate buffer solution (PBS) of pH 7.0, the oxidation current increased linearly with two concentration intervals of methyldopa, one is 1.0×10?8–1.0×10?6 M and the other is 1.0×10?6–4.5×10?5 M. The detection limit (3σ) obtained by SWV was 9.0 nM. The modified electrode was successfully applied for simultaneous determination of methyldopa and hydrochlorothiazide. Finally, the proposed method was applied to the determination of methyldopa and hydrochlorothiazide in some real samples. 相似文献
5.
Saraji M Khalili Boroujeni M Hajialiakbari Bidgoli AA 《Analytical and bioanalytical chemistry》2011,400(7):2149-2158
Dispersive liquid–liquid microextraction (DLLME) and hollow fiber liquid–liquid–liquid microextraction (HF-LLLME) combined
with HPLC–DAD have been applied for the determination of three narcotic drugs (alfentanil, fentanyl, and sufentanil) in biological
samples (human plasma and urine). Different DLLME parameters influencing the extraction efficiency such as type and volume
of the extraction solvent and the disperser solvent, concentration of NaOH, and salt addition were investigated. In the HF-LLLME,
the effects of important parameters including organic solvent type, concentration of NaOH as donor solution, concentration
of H2SO4 as acceptor phase, salt addition, stirring rate, temperature, and extraction time were investigated and optimized. The results
showed that both extraction methods exhibited good linearity, precision, enrichment factor, and detection limit. Under optimal
condition, the limits of detection ranged from 0.4 to 1.9 μg/L and from 1.1 to 2.3 μg/L for DLLME and HF-LLLME, respectively.
For DLLME, the intra- and inter-day precisions were 1.7–6.4% and 14.2–15.9%, respectively; and for HF-LLLME were 0.7–5.2%
and 3.3–10.1%, respectively. The enrichment factors were from 275 to 325 and 190 to 237 for DLLME and HF-LLLME, respectively.
The applicability of the proposed methods was investigated by analyzing biological samples. For analysis of human plasma and
urine samples, HF-LLLME showed higher precision, more effective sample clean-up, higher extraction efficiency, lower organic
solvent consumption than DLLME. 相似文献
6.
Fatemeh Vahedi Mojtaba Sankian Malihe Moghadam Maryam Mohaddesfar Sirous Ghobadi Abdol Reza Varasteh 《Applied biochemistry and biotechnology》2011,163(7):895-905
Chenopodium album is a weedy annual plant in the genus Chenopodium. C. album pollen represents a predominant allergen source in Iran. The main C. album pollen allergens have been described as Che a 1, Che a 2, and Che a 3. The aim of this work was to clone the Che a 1 in Escherichia coli to establish a system for overproduction of the recombinant Che a 1 (rChe a 1). In order to clone this allergen, the pollens
were subjected to RNA extraction. A full-length fragment encoding Che a 1 was prepared by polymerase chain reaction amplification
of the first-strand cDNA synthesized from extracted RNA. Cloning was carried out by inserting the cDNA into the pET21b (+)
vector, thereafter the construct was transformed into E. coli Top10 cells and expression of the protein was induced by IPTG. The rChe a 1 was purified using histidine tag in recombinant
protein by means of Ni–NTA affinity chromatography. IgE immunoblotting, ELISA, and inhibition ELISA were done to evaluate
IgE binding of the purified protein. In conclusion, the cDNA for the major allergen of the C. album pollen, Che a 1, was successfully cloned and rChe a 1 was purified. Inhibition assays demonstrated allergic subjects sera
reacted with rChe a 1 similar to natural Che a 1 in crude extract of C. album pollen. This study is the first report of using the E. coli as a prokaryotic system for Che a 1 cloning and production of rChe a 1. 相似文献
7.
Malihe Javan Khoshkholgh Hamid Reza Bijanzadeh Jürgen H. Gross 《Tetrahedron letters》2008,49(49):6965-6968
An efficient synthesis of tetracyclic uracil derivatives (polycyclic pyrans) is achieved via domino Knoevenagel-hetero-Diels-Alder reactions of O-propargylated salicylaldehyde derivatives with 1,3-dimethylbarbituric acid in water as solvent in the presence of CuI. The products are formed in good yields. 相似文献
8.
Samadi Morasae Zirak Mohammad Naseri Amene Kheirabadi Malihe Ebrahimi Mahdi Moshfegh Alireza Z. 《Research on Chemical Intermediates》2019,45(4):2197-2254
Research on Chemical Intermediates - Photocatalysis using semiconductors has emerged as a promising wastewater treatment process to overcome the major challenges faced by conventional technologies.... 相似文献
9.
Mohammad Saraji Malihe Khalili Boroujeni 《Analytical and bioanalytical chemistry》2014,406(8):2027-2066
During the past 7 years and since the introduction of dispersive liquid–liquid microextraction (DLLME), the method has gained widespread acceptance as a simple, fast, and miniaturized sample preparation technique. Owing to its simplicity of operation, rapidity, low cost, high recovery, and low consumption of organic solvents and reagents, it has been applied for determination of a vast variety of organic and inorganic compounds in different matrices. This review summarizes the DLLME principles, historical developments, and various modes of the technique, recent trends, and selected applications. The main focus is on recent technological advances and important applications of DLLME. In this review, six important aspects in the development of DLLME are discussed: (1) the type of extraction solvent, (2) the type of disperser solvent, (3) combination of DLLME with other extraction methods, (4) automation of DLLME, (5) derivatization reactions in DLLME, and (6) the application of DLLME for metal analysis. Literature published from 2010 to April 2013 is covered. 相似文献
10.
We have prepared a highly selective and efficient sorbent for the simultaneous separation and preconcentration of lead and cadmium ions from milk and water samples. An ionic liquid was deposited on the surface of magnetic nanoparticles (IL-MNPs) and used for solid phase extraction of these ions. The IL-MNPs carrying the target metals were then separated from the sample solution by applying an external magnetic field. Lead and cadmium were almost quantitatively retained by the IL-MNPs, and then eluted with nitric acid. The effect of different variables on solid phase extraction was investigated. The calibration curve is linear in the range from 0.3 to 20?ng mL?1 of Cd(II), and from 5 to 330?ng mL?1 of Pb(II) in the initial solution. Under optimum conditions, the detection limits are 1.61 and 0.122?μg?L-1 for Pb(II) and Cd(II) respectively. Relative standard deviations (n?=?10) were 2.87?% and 1.45?% for 0.05?μg?mL-1 and 0.2?μg?mL-1 of Cd (II) and Pb (II) respectively. The preconcentration factor is 200 for both of ions. Figure
A novel, highly selective and efficient sorbent, was prepared and applied for separation and preconcentration of lead and cadmium from real samples. Lead and cadmium could be quantitatively retained by ionic liquid-modified magnetite nanoparticles and then easily separated from the aqueous solution by applying an external magnetic field; so, no filtration or centrifugation was necessary. 相似文献