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11.
Removal of phosphate by aluminum oxide hydroxide   总被引:17,自引:0,他引:17  
The development and manufacture of an adsorbent to remove phosphate ion for the prevention of eutrophication in lakes are very important. The characteristics of phosphate adsorption onto aluminum oxide hydroxide were investigated to estimate the adsorption isotherms, the rate of adsorption, and the selectivity of adsorption. Phosphate was easily adsorbed onto aluminum oxide hydroxide, because of the hydroxyl groups. The adsorption of phosphate onto aluminum oxide hydroxide was influenced by pH in solution: the amount adsorbed was greatest at pH 4, ranging with pH from 2 to 9. The optimum pH for phosphate removal by aluminum oxide hydroxide is 4. The selectivity of phosphate adsorption onto aluminum oxide hydroxide was evaluated based on the amount of phosphate ion adsorbed onto aluminum oxide hydroxide from several anion complex solutions. It is phosphate that aluminum oxide hydroxide can selectively adsorb. The selectivity of phosphate onto aluminum oxide hydroxide was about 7000 times that of chloride. This result indicated that the hydroxyl groups on aluminum oxide hydroxide have selective adsorptivity for phosphate and could be used for the removal of phosphate from seawater.  相似文献   
12.
We study reflection diffuse optical tomography using two-dimensional (2D) continuous-wave source-detector arrays on the surface of semi-infinite medium, aiming at imaging the perfusion and the hemoglobin oxygen saturation variation of human cerebral cortex with brain activation. We had previously formulated the inverse problem with Moore-Penrose inversion. When we use simple regularization in this inverse problem, the reconstruction sensitivity decreases markedly with the depth so that the signal in the deep range may be masked by an unwanted signal in the shallow range. In this paper, we propose a depth-adaptive regularized reconstruction, in which we assign a smaller regularization parameter with the depth. We demonstrate improvement of the three-dimensional (3D) reconstruction uniformity using the proposed scheme.  相似文献   
13.
In inertial confinement fusion research, uniform laser irradiation on a fusion target is a key issue. We propose a new method of beam smoothing in which we use three-directional spectral dispersion to reduce the coherent speckle that is unavoidable in the usual two-directional spectral-dispersion scheme. We have used this smoothing technique in a Nd:glass laser system and have demonstrated that the coherent speckle is reduced by a factor of 2.9 from that in two-directional spectral dispersion.  相似文献   
14.
Treatment of N-tosyliodoaziridine derivatives with Et(3)B efficiently produces various azahomoallyl radical (2-akenylamidyl radical) species which give oxygen-functionalized pyrrolidine derivatives through iodine atom transfer [3 + 2] cycloaddition with electron-rich alkenes such as enol ethers and ketene acetal. The present cycloaddition reaction proceeds regioselectively via C-N bond cleavage of an aziridinylalkyl radical intermediate and addition of the resulting azahomoallyl radicals to the terminal carbon of an alkene. The reaction of alkenes with the cyclohexenylamidyl radical generated from an optically active bicyclic iodoaziridine [(1S,2S,6S)-2-iodo-7-(p-toluenesulfonyl)-7-azabicyclo[4.1.0]heptane, 94% ee] also proceeds to give optically active octahydroindole derivatives (84-93% ee).  相似文献   
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Methylenecyclopropanes carrying a hydroxymethyl group at the ring underwent stereoselective allylindation with allylindium sesquiiodide to afford the allylated products, in which the allyl group was delivered at the external sp2 carbon via cyclopropylindium intermediates. The reaction of ethyl 2-cyclopropylideneacetate and triallylindium afforded the 1,4-adduct along with dimeric products.  相似文献   
17.
A novel molecular sensor using anthracene bearing two amidopyridines emits blue fluorescence in the presence of succinic acid and green fluorescence in the presence of malonic acid, and its fluorescence intensity increased upon binding. Using this molecular sensor, we succeeded in detecting the difference of one carbon atom between succinic acid and malonic acid with the naked-eye. Furthermore, when methylmalonic acid was dissolved in urine to provide a model system for methylmalonic aciduria, the fluorescence changed from blue to green, and methylmalonic acid was successfully detected with the naked-eye.  相似文献   
18.
In our photo‐induced immobilization technique for an antibody (IgG) using azopolymers, the introduction of COOH and NMe2 into the azopolymers, which can introduce surface charges, strongly affected the immobilization properties such as the efficiency of immobilization and the activity of the immobilized IgG (i.e., the orientation of the immobilized IgG). The introduction of COOH promoted a more active orientation of the immobilized IgG. The orientation was determined during the adsorption process onto the azopolymer surface in solution before photo‐immobilization, and was maintained during the photo‐immobilization. The surface charge of the azopolymer appears to be an important factor for IgG orientation, which involves electrostatic interactions between its Fab and the azopolymer surface.

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19.
The purpose of this article is to study an existence of p-bases and mainly to give some regularity criteria for semilocal rings essentially of finite type over fields.  相似文献   
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