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161.
Garcia A Peniche-Covas C Chico B Simpson BK Villalonga R 《Macromolecular bioscience》2007,7(4):435-439
Chitosan was chemically branched with ferrocene moieties and further used as a support for the immobilization of horseradish peroxidase on a glassy carbon electrode. The reagentless biosensor device showed a linear amperometric response toward hydrogen peroxide concentrations between 35 x 10(-6) M and 2.0 x 10(-3) M. The biosensor reached 95% of the steady-state current in about 20 s and its sensitivity was 28.4 x 10(-3) microA x M(-1). The enzyme electrode retained 94% of its initial activity after 2 weeks of storage at 4 degrees C in 50 x 10(-3) M sodium phosphate buffer at pH 7.0. 相似文献
162.
We consider two problems regarding vanishing patterns in the Betti table of edge ideals I over any fixed field. First, we show that the j-strand is connected if \(j=3\) (for \(j=2\) this is easy and known), and give examples where the j-strand is not connected for any \(j>3\). Next, we apply our result on strand connectivity to establish the subadditivity conjecture for edge ideals, \(t_{a+b}(I)\le t_a(I)+t_b(I)\), in case \(b=2,3\) (the case \(b=1\) is known). Here \(t_i(I)\) denote the maximal shifts in the minimal free resolution of S / I over its polynomial algebra. 相似文献
163.
164.
Adsorption of strontium on illite type clay has been studied as a function of shaking time, the ratio of solution volume to weight of clay and the concentration of adsorbate, using 90Sr as a tracer. The adsorption experiments were carried out using the batch method and initial Sr2+ ion concentrations ranged from 10–6 to 10–1 M. The influence of Ca2+ and Ba2+ cations on Sr adsorption were also studied. These effects are correlated with the ionic radii of alkaline earth ions present in the solution. The Freundlich and Dubinin Radushkevich (D-R) isotherm have been applied to the data and the parameters of the isotherm equations were calculated. The mean energy of adsorption, E was also calculated from the adsorption energy constant, K and maximum capacity X
m values were determined from linearized D-R equation. From empirical Freundlich parameters a site distribution function was calculated. 相似文献
165.
166.
Mehmet Bilgin 《The Journal of chemical thermodynamics》2010,42(4):530-535
Experimental (liquid + liquid) equilibrium data for the mixtures of (heptane, or hexane, or cyclohexane + toluene + 1,3-dimethyl-2-imidazolidinone) were determined at T = 298.15 K and P = 101.3 kPa. The solubility (binodal) curves and tie-line end compositions are reported for the related mixtures and presented as complete phase diagrams. Distribution coefficients and separation factors were evaluated for the immiscibility region. The reliability of the experimental tie-line results was verified by using the Othmer–Tobias correlation. The experimental tie-line data were correlated by UNIQUAC model, which gave satisfactory representation for the systems. It was observed that the separation of toluene from cyclohexane is easier to achieve than from heptane and hexane. 相似文献
167.
A simple and convenient synthesis of orthogonally protected multi-tethered, optically pure 2-ketopiperazine, diketopiperazine, 2-ketodiazepane and 3-aminopyrrolidone scaffolds for Fmoc combinatorial chemistry has been developed. It utilizes accessible chiral amino acid precursors, sequentially applying reductive alkylation, dipeptide coupling and regioselective ring formation as key steps. These scaffolds are expansion of our ‘pool of privileged building blocks’ and can introduce valuable drug-like properties in three independent directions to any medicinally relevant piperazine-, diazepane- and pyrrolidone-based motif by ‘around-the-scaffold’ drug optimization. The synthetic routes reported in this work are general and applicable for the preparation of a diverse library of scaffolds, controlling chirality, arm position and length as well as the nature of functional moieties at the arms for further diversification in three independent directions. In addition, these building blocks have a wide application scope in managing fast and efficient multi-cyclic optimization processes in the combinatorial chemistry and drug design fields. 相似文献
168.
Maxime Gabella Jerome P. Gauntlett Eran Palti James Sparks Daniel Waldram 《Communications in Mathematical Physics》2010,299(2):365-408
We use the formalism of generalized geometry to study the generic supersymmetric AdS 5 solutions of type IIB supergravity that are dual to ${\mathcal{N}=1}We use the formalism of generalized geometry to study the generic supersymmetric AdS
5 solutions of type IIB supergravity that are dual to N=1{\mathcal{N}=1} superconformal field theories (SCFTs) in d = 4. Such solutions have an associated six-dimensional generalized complex cone geometry that is an extension of Calabi-Yau
cone geometry. We identify generalized vector fields dual to the dilatation and R-symmetry of the dual SCFT and show that they are generalized holomorphic on the cone. We carry out a generalized reduction
of the cone to a transverse four-dimensional space and show that this is also a generalized complex geometry, which is an
extension of K?hler-Einstein geometry. Remarkably, provided the five-form flux is non-vanishing, the cone is symplectic. The
symplectic structure can be used to obtain Duistermaat-Heckman type integrals for the central charge of the dual SCFT and
the conformal dimensions of operators dual to BPS wrapped D3-branes. We illustrate these results using the Pilch-Warner solution. 相似文献
169.
Eran Zahavy Vered Heleg-Shabtai Yossi Zafrani Daniele Marciano Shmuel Yitzhaki 《Journal of fluorescence》2010,20(1):389-399
Fluorescent semiconductor nanocrystals (q-dots) benefit from practical features such as high fluorescence intensity, broad
excitation band and emission diameter dependency. These unique spectroscopic characterizations make q-dots excellent candidates
for new fluorescent labels in multi-chromatic analysis, such as Flow-Cytometry (FCM). In this work we shall present new possibilities
of multi-labeling and multiplex analysis of pathogenic bacteria, by Flow-Cytometry (FCM) analysis and new specific IgG—q-dots
conjugates. We have prepared specific conjugates against B. anthracis spores (q-dots585-IgGαB. anthracis and q-dots655-IgGαB.anthracis). These conjugates enabled us to achieve double staining of B. anthracis spores which improve the FCM analysis specificity versus control Bacillus spores. Moreover, multiplexed analysis of B. anthracis spores and Y. pestis bacteria was achieved by using specific antibodies labeled with different q-dots to obtain: q-dots585-IgGαB. anthracis and q-dots655-IgGαY.pestis, each characterized by its own emission peak as a marker. Specific and sensitive multiplex analysis for both pathogens has
been achieved, down to 103 bacteria per ml in the sample. 相似文献
170.
Eran Nevo 《Geometriae Dedicata》2015,178(1):103-110