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排序方式: 共有170条查询结果,搜索用时 31 毫秒
121.
CdCO3 nanostructures were synthesized via simple hydrothermal method by Cd(NO3)2, ethylenediamine and hydrazine as reagents. The products were characterized with X-ray diffraction scanning electron microscopy, energy-dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy. Different parameter’s effect on product size and morphology were investigated. 相似文献
122.
A multicomponent, catalyst-free reaction for the synthesis of fused 6-amino-3-methyl-4-aryl-1H-pyrazolo [3,4-b] pyridine-5-carbonitrile from 3-amino-5-methylpyrazole, malononitrile, and substituted aldehydes under ultrasound irradiation in short reaction times (8–10 min) with good yields (85–98%) is reported.
123.
124.
Manouchehr Ghamsari David A. Herron 《Transactions of the American Mathematical Society》1999,351(8):3197-3216
We characterize bilipschitz homogeneous Jordan curves by utilizing quasihomogeneous parameterizations. We verify that rectifiable bilipschitz homogeneous Jordan curves satisfy a chordarc condition. We exhibit numerous examples including a bilipschitz homogeneous quasicircle which has lower Hausdorff density zero. We examine homeomorphisms between Jordan curves.
125.
Sina Sarikhani Manouchehr Mirshahi Mohammad Reza Gharaati Tooran Mirshahi 《Applied biochemistry and biotechnology》2010,162(5):1249-1257
As IgM is the first isotype of antibody which appears in blood after initial exposure to a foreign antigen in the pattern
of primary response, detection, and quantification of this molecule in blood seems invaluable. To approach these goals, generation,
and characterization of a highly specific mAb (monoclonal antibody) against human IgM were investigated. Human IgM immunoglobulins
were used to immunize Balb/c mice. Spleen cells taken from the immunized animals were fused with SP2/O myeloma cells using
PEG (polyethylene glycol, MW 1450) as fusogen. The hybridomas were cultured in HAT containing medium and supernatants from
the growing hybrids were screened by enzyme-linked immunosorbent assay (ELISA) using plates coated with pure human IgM and
the positive wells were then cloned at limiting dilutions. The best clone designated as MAN-1, was injected intraperitoneally
to some Pristane-injected mice. Anti-IgM mAb was purified from the animals’ ascitic fluid by protein-G sepharose followed
by DEAE-cellulose ion exchange chromatography. MAN-1 interacted with human IgM with a very high specificity and affinity.
The purity of the sample was tested by SDS-PAGE and the affinity constant was measured
( K\texta = \text3.\text5 ×\text10\text9\textM\text - 1 ) \left( {{K_{\text{a}}} = {\text{3}}.{\text{5}} \times {\text{1}}{0^{\text{9}}}{{\text{M}}^{{\text{ - 1}}}}} \right) . Immunoblotting and competitive ELISA were done and the results showed that the harvested antibody recognizes a conformational
epitope on the μ chain of human IgM and there was no cross-reactivity with other subclasses of immunoglobulins. Furthermore,
isotyping test was done and the results showed the subclass of the obtained mAb which was IgG1κ. 相似文献
126.
Peyman Salehi Minoo Dabiri Ali Zolfigol Ali Bodaghi Fard 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1113-1121
The nucleophilic ring opening reactions of epoxides by aliphatic alcohols and water are achieved efficiently in the presence of catalytic amounts of silica sulfuric acid with high degree of regioselectivity. The catalyst is reusable and can be applied several times without any decrease in the yield of reactions. 相似文献
127.
Manouchehr Zaker 《Discrete Mathematics》2006,306(23):3166-3173
Given a graph G, by a Grundy k-coloring of G we mean any proper k-vertex coloring of G such that for each two colors i and j, i<j, every vertex of G colored by j has a neighbor with color i. The maximum k for which there exists a Grundy k-coloring is denoted by Γ(G) and called Grundy (chromatic) number of G. We first discuss the fixed-parameter complexity of determining Γ(G)?k, for any fixed integer k and show that it is a polynomial time problem. But in general, Grundy number is an NP-complete problem. We show that it is NP-complete even for the complement of bipartite graphs and describe the Grundy number of these graphs in terms of the minimum edge dominating number of their complements. Next we obtain some additive Nordhaus-Gaddum-type inequalities concerning Γ(G) and Γ(Gc), for a few family of graphs. We introduce well-colored graphs, which are graphs G for which applying every greedy coloring results in a coloring of G with χ(G) colors. Equivalently G is well colored if Γ(G)=χ(G). We prove that the recognition problem of well-colored graphs is a coNP-complete problem. 相似文献
128.
129.
Mohammad Nikpassand Manouchehr Mamaghani Farhad Shirini Khalil Tabatabaeian 《Ultrasonics sonochemistry》2010,17(2):301-305
Fused polycyclic 4-aryl-3-methyl-4,7-dihydro-1H-pyrazolo[3,4-b]pyridines were obtained in a three-component regioselective reaction of 5-amino-3-methyl-1H-pyrazole, 2H-indene-1,3-dione and arylaldehydes in ethanol under ultrasound irradiation. This rapid method produced the products in short reaction times (4–5 min) and excellent yields (88–97%). 相似文献
130.
In this paper, a novel dispersion-shifted multi-clad optical fiber with very small bending loss and ultra-high bit-rate applicable for large capacity information transmission systems is presented. To decrease dispersion and higher-order dispersion effects at λ = 1.55 μm, a weighted pulse broadening factor and genetic algorithm (GA) optimization technique is used. Compared to the works reported previously, this method can precisely set the zero-dispersion wavelength. This kind of dispersion-shifted fibers has dispersion, dispersion slope, mode field diameter (MFD), effective area and quality factor within −1.40 × 10−4 to −8.44 × 10−2 ps/km nm, 3.06 × 10−2 to −4.07 × 10−2 ps/km nm2, 5.56−5.85 μm, 119.25−176.42 μm2 and 3.49-5.27 at λ = 1.55 μm, respectively. Besides, by applying dispersion at λ = 1.55 μm as the cost function, dispersion of about 1.31 × 10−8 ps/km nm is obtained. Thus, this novel optical fiber can be used in long-haul high information-transmission capacity communication systems. 相似文献