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61.
Seaweeds can play a vital role in plant growth promotion. Two concentrations (5 and 10 mg/mL) of soluble polysaccharides extracted from the green macroalgae Ulva fasciata and Ulva lactuca were tested on Zea mays L. The carbohydrate and protein contents, and antioxidant activities (phenols, ascorbic, peroxidase, and catalase) were measured, as well as the protein banding patterns. The soluble polysaccharides at 5 mg/mL had the greatest effect on the base of all of the parameters. The highest effects of soluble polysaccharides on the Zea mays were 38.453, 96.76, 4, 835, 1.658, 7.462, and 38615.19, mg/mL for carbohydrates, proteins, phenol, µg ascorbic/mL, mg peroxidase/g dry tissue, and units/g tissue of catalase, respectively. The total number of protein bands (as determined by SDS PAGE) was not changed, but the density of the bands was correlated to the treatments. The highest band density and promoting effect were correlated to 5 mg/mL soluble polysaccharide treatments extracted from Ulva fasciata in Zea mays, which can be used as a biofertilizer.  相似文献   
62.
In this paper, we introduce a trivariate q-polynomials \(F_n(x,y,z;q)\) as a general form of Hahn polynomials \(\psi _n^{(a)}(x|q)\) and \(\psi _n^{(a)}(x,y|q)\). We represent \(F_n(x,y,z;q)\) by two operators: the homogeneous q-shift operator \(L(b\theta _{xy})\) given by Saad and Sukhi (Appl Math Comput 215:4332–4339, 2010), and the Cauchy companion operator \(E(a,b;\theta )\) given by Chen (q-Difference Operator and Basic Hypergeometric Series, 2009) to derive the generating function, symmetric property, Mehler’s formula, Rogers formula, another Roger-type formula, linearization formula, and an extended Rogers formula for the trivariate q-polynomials. Then, we give the corresponding formulas for our new definitions of Hahn polynomials \(\psi _n^{(a)}(x|q)\) and \(\psi _n^{(a)}(x,y|q)\) by representing Hahn polynomials by the operators \(L(b\theta _{xy})\) and \(E(a,b;\theta )\), and by a special substitution in the trivariate q-polynomials \(F_n(x,y,z;q)\).  相似文献   
63.
A vibrating sample magnetometer (VSM) has been used to study the field-dependent magnetization, M(H), of the d5?d7 metal acetates [M(OAc)2.nH2O], metal β?diketonate complexes [M(tba)2(H2O)2] and the macromolecular polymers [M(tba)2(4,4-bipy)]n (where, M = Mn(II), Fe(II), and Co(II), OAc = O2CCH3, tba = deprotonated 3-benzoyl-1.1.1-trifluoroacetone, and 4,4-bipy = 4,4′-bipyridine). The magnetic field strength (H) was applied in the range of 0?104 Oe at ambient temperature (ca. 23°C). The experimental results showed that the d5?d7 metal acetate, complexes and polymers exhibit low paramagnetic properties excepting [Fe(tba)2(4,4-bipy)]n polymer, which had negative magnetization M(emu/g) showing diamagnetic properties in the range 0?104 Oe. The magnetization was almost equal to zero without an applied magnetic field (H(Oe)) for each d5?d7 metal acetate, complex, and polymer. The linear M(H) curve had a magnetic saturation for iron and manganese acetate species at the magnetic field strengths of 3.1 × 103 and 4.7 × 103 Oe, respectively. The external magnetic field reached 9.0 × 103 Oe without any saturation magnetization for the cobalt compounds. The coordination effect of 3-benzoyl-1.1.1-trifluoroacetone (H-tba) and 4,4′-bipyridine (4,4′-bipy) ligands on the field-dependent magnetization M(H) and paramagnetic behavior of d5?d7 metal atoms is discussed. The field-dependent magnetization M(H) curves of metal β?diketonate complexes and the polymers including d5?d7 metal acetates showed a weak field octahedral geometry.  相似文献   
64.
In this paper, we consider a quite general class of reaction‐diffusion equations with cubic nonlinearities and with random Neumann boundary conditions. We derive rigorously amplitude equations, using the natural separation of time‐scales near a change of stability and investigate whether additive degenerate noise and random boundary conditions can lead to stabilization of the solution of the stochastic partial differential equation or not. The nonlinear heat equation (Ginzburg–Landau equation) is used to illustrate our result. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
65.
66.
Journal of Radioanalytical and Nuclear Chemistry - The current work aims at the preparation and characterization of novel composite materials of acrylic acid/charcoal/montmorillonite (MMT) (PAACM...  相似文献   
67.
Photodegradation of tenoxicam was investigated under different reaction conditions. After 60 min of exposure to UV light, the photodegradation was extensive, and the maximum and minimum in the UV-visible spectrum were shifted to shorter and longer wavelengths, respectively. Ethanol exerted a photostabilizing effect on tenoxicam. Tenoxicam is more stable in acidic and basic media than in neutral solution. Increasing light intensity or temperature causes an increase in the rate of photodegradation. The photodegradation of tenoxicam was found to follow first-order kinetics under all these conditions.  相似文献   
68.
A new route has been devised, leading to the production of VOX3 molecules where X=F, Br and I by an on-line process using vanadium oxytrichloride, VOCl3 as a starting compound passed over the following heated salts NaF, KBr and KI at 375, 700 and 550°C, respectively. The products have been characterized by the IR spectra of their vapors. The low resolution gas phase on-line Fourier transform infrared spectra reported for the first time show strong bands with PQR type structure, centered at 1058, 1035, 1030 and 1025 cm−1 assigned to the ν1(a1), the O=V stretching fundamental mode of VOF3, VOCl3, VOBr3 and VOI3, respectively.  相似文献   
69.
In this paper we report the results of an extensive experimental kinetic study carried out on the novel ethylene trimerization catalyst system, comprising the chromium source [CrCl3(thf)3] (thf=tetrahydrofuran), a Ph2P‐N(iPr)‐P(Ph)‐N(iPr)H (PNPNH) ligand (Ph=phenyl, iPr=isopropyl), and triethylaluminum (AlEt3) as activator. It could be shown that the initial activity shows a first‐order dependency on the ethylene concentration. Also, a first‐order dependency was found for the catalyst concentration. The initial activity follows a typical Arrhenius behavior with an experimentally determined activation energy of 52.6 kJ mol?1. At elevated temperatures (ca. 80 °C), a significant deactivation was observed, which can be tentatively traced back to a ligand rearrangement in the presence of AlEt3. After a fast initial phase, a pronounced ‘kink’ in the ethylene‐uptake curve is observed, followed by a slow, almost linear, further increase of the total ethylene consumption. The catalyst composition, in particular the ligand/chromium and the cocatalyst/chromium molar ratio, has a strong impact on the catalytic performance of the trimerization of ethylene.  相似文献   
70.
Density, sound velocity, and viscosity of 1-ethyl-3-methylimidazolium bromide, [Emim][Br], in aqueous solutions of tri-potassium phosphate with salt weight fractions (ws = 0.00, 0.10, 0.15, and 0.20) have been measured as a function of concentration of [Emim][Br] at atmospheric pressure and T = (298.15, 303.15, 308.15, 313.15, and 318.15) K. The apparent molar volume, isentropic compressibility, apparent isentropic compressibility, and relative viscosity values have been evaluated from the experimental data. The partial molar volume and isentropic compressibility at infinite dilution, and viscosity B-coefficient obtained from these data have been used to calculate the corresponding transfer parameters for the studied IL from water to the aqueous tri-potassium phosphate solutions. Also, an empirical equation was satisfactorily used to correlate the experimental viscosity data.  相似文献   
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