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11.
R. Trettin T. Grischek G. Strauch G. Malleean W. Nestler 《Isotopes in environmental and health studies》2013,49(4):331-350
Abstract Flow times and infiltration behaviour are very important for water extraction from riverbank filtration. Both the chloride content and the isotopic composition of oxygen (δ18O) were found to be suitable indicators for the conditions encountered in the middle course of the River Elbe near Torgau. The ranges for Elbe water were measured to be 20–43 mg Cl/l (1995-97) and -11 to -8.5‰ δ18O (1993-97). Both methods permitted flow-time spectra at two adjacent sampling profiles incorporating river and production wells to be obtained, indicating the preferred flow paths and the vertical extension of the riverbank filtrate plume in the aquifer. However, since the differences between the mean values for river water and regional groundwater were too small the percentage of river water abstracted from production wells could not be calculated. 相似文献
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Ashu Chaudhary R. V. Singh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):615-626
Fourteen- to eighteen-membered tetraamide macrocyclic ligands N 4 L 1 -N 4 L 4 have been prepared by the condensation of 1,2-diaminoethane or 1,3-diaminopropane with malonic or succinic acid in the presence of condensing reagents dicyclohexylcarbodiimide and 4-dimethylaminopyridine. On reduction, these macrocyclic ligands give a new series of tetraazamacrocycles MacL 1 -MacL 4 which form complexes with tin(II) chloride. The ligands and their complexes were characterized by elemental analyses, molecular weight determinations, infrared and 1 H NMR spectral studies. The hexacoordinated state for tin has been confirmed by spectral studies. An octahedral geometry for these complexes has been proposed as the binding sites are the nitrogen atoms of the macrocycles. On the basis of the chemical composition the representation of the complexes as [Sn(MacL n )Cl 2 ] (n = 1-4) has been established. The ligands and their complexes also have been screened for their antifungal and antibacterial activities and the findings have been reported and explained. 相似文献
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Nadia Al-Saedi Manjree Agarwal Shahidul Islam Yong-Lin Ren 《Molecules (Basel, Switzerland)》2021,26(8)
Australian sweet lupin, the largest legume crop grown in Western Australia, is receiving global attention from the producers of new foods. To understand the effect of protein on cheese yield, lupin milk proteins were separated from the first, second, and third filtrations by cheesecloths. However, proteins from the first and second were analyzed using two-dimensional polyacrylamide gel electrophoresis; then, the isolated proteins associated with cheese production were identified. The research also focused on identifying the optimal method of cheese production based on the coagulation process, temperature, yield, and sensory evaluation. Lupin curds from the two cultivars, Mandelup and PBA Jurien, were produced using vinegar, lemon juice, starter culture, vegetable rennet enzyme as coagulant, as well as curd generated using starter culture and vegetable rennet enzyme. Cow’s milk was used as a control. The results indicated that first-time filtration produced better extraction and higher yield of lupin proteins and cheese than the second filtration. A sensory analysis indicated that lupin cheese produced from PBA Jurien lupin milk using vinegar, 7.80% expressed as acetic acid, and ground in 45 °C water, was the most acceptable. The cheeses were examined for their protein, carbohydrates, fat, ash, and moisture contents. The concentration of protein was approximately 27.3% and 20.6%, respectively, in the cheese from PBA Jurien and Mandelup. These results suggest that lupin milk can adequately supply the proteins needed in human diets and, thus, could be used in the production of many existing products that require animal milk as an input. 相似文献
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Osamu Takimura Hiroyuki Fuse Katsuzi Murakami Kazuo Kamimura Yukiho Yamaoka 《应用有机金属化学》1996,10(9):753-756
Uptake and reduction of arsenate [AS(V)] by Dunaliella sp. cells were determined to investigate the metabolic processes of arsenic in the alga. Cellular uptake of arsenic by Dunaliella sp. cells was markedly affected by the form of arsenic in the medium. The content of arsenic taken up by Dunaliella sp. cells increased rapidly with time on addition of As(V) to the medium. However, in the case of addition of arsenite [As(III)], the gradient of arsenic uptake by Dunaliella sp. cells was low, and arsenic content was small. In the water-soluble fraction of arsenic taken up by Dunaliella sp. cells with exposure to As(V), arsenic was in the forms of organic arsenic, As(V) and As(III). The content of As(V) in the water-soluble fraction increased with exposure time. The content of As(III) also increased with time, but remained constant after 5 h of exposure. On the other hand, organic arsenic content was small and did not increase with time. It was found that Dunaliella sp. takes up As(V) and readily reduces it to As(III) 相似文献
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We show that, if E is a commutative MU-algebra spectrum such that is Landweber exact over , then the category of -comodules is equivalent to a localization of the category of -comodules. This localization depends only on the heights of E at the integer primes p. It follows, for example, that the category of -comodules is equivalent to the category of -comodules. These equivalences give simple proofs and generalizations of the Miller-Ravenel and Morava change of rings theorems. We also deduce structural results about the category of -comodules. We prove that every -comodule has a primitive, we give a classification of invariant prime ideals in , and we give a version of the Landweber filtration theorem. 相似文献
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Ying Yang Jingxue Yin Chunhua Jin 《Mathematical Methods in the Applied Sciences》2014,37(12):1736-1754
This paper is concerned with the existence and attractivity of time periodic solutions for one‐dimensional Nicholson's blowflies model with nonlinear diffusion. By constructing some suitable Lyapunov functionals and combining with Leray–Schauder fixed point theorem, we establish the existence of nonnegative time periodic solutions. Using the method of upper and lower solutions and its associated monotone iterations, we obtain the existence of the attractor for this model. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献