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991.
Sadin Özdemir M. Kadir Oduncu Ersin Kılınç Mustafa Soylak 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):185-193
Bacillus vallismortis and Bacillus mojavensis were loaded onto Amberlite XAD-4 resin and used for solid phase extraction (SPE) of uranium(VI). A quick and simple UV–Vis spectrophotometric method was used to determine U(VI) ion. The best experimental conditions were determined as being a pH of 5.0; a sample flow rate of 2.0 mL min?1; 200.0 mg of biosorbent; 800 mg of Amberlite XAD-4, and 5.0 mL of 1 mol L?1 HCl as desorption solution for both immobilized bacteria. The preconcentration factors were achieved as 80 for both solid phase extractor. The developed methods were validated by applying to reference water and tea samples. 相似文献
992.
Low-cost pistachio shells were used for the production of small pore carbon molecular sieves by the benzene deposition method. The prepared materials were characterized by the Brunauer–Emmett–Teller surface area and scanning electron microscopy. The deposition temperature and the deposition time parameters, which affect the formation of carbon molecular sieves, were examined. The effect of deposition temperature was examined in the range of 700–900°C, while deposition time was examined between 30 and 60?min. The optimum surface area of the carbon molecular sieve prepared by benzene deposition was 895?m2/g at 800°C. The average pore diameter of the carbon molecular sieve was 0.27?nm, principally denoted ultramicropore characteristics. The obtained values of the pore size distributions of the prepared carbon molecular sieves were in the range of 0.26–0.29?nm. 相似文献
993.
A New Table of Binary/Ternary Mixed Covering Codes 总被引:1,自引:0,他引:1
A table of upper bounds for K3,2(n1,n2;R), the minimum number of codewords in a covering code with n1 ternary coordinates, n2 binary coordinates, and covering radius R, in the range n = n1 + n2 13, R 3, is presented. Explicit constructions of codes are given to prove the new bounds and verify old bounds. These binary/ternary covering codes can be used as systems for the football pool game. The results include a new binary code with covering radius 1 proving K2(13,1) 736, and the following upper bound for the football pool problem for 9 matches: K3(9,1) 1356. 相似文献
994.
995.
Emin Özçag 《Proceedings Mathematical Sciences》1998,108(1):41-49
The existence of the neutrix convolution product of distributionx ? r Inx ? andx + ?3 is proved and some convolution products are evaluated. 相似文献
996.
Unruh's detector calculation is used to study the effect of the defect angle in a space-time with a cosmic string for both the excitation and deexcitation cases. It is found that a rotating detector results in a non-zero effect for both finite (small) and infinite (large) time. 相似文献
997.
Sabri Cevik Mehmet Poyraz Musa Sar Orhan Büyükgüng?r 《Journal of chemical crystallography》2007,37(7):497-502
The hydrothermal reaction of a mixture of VOSO4 · xH2O, 1,2,4,5-benzenetetracarboxylic acid (pyromellitic acid) and 0.1 M H2SO4 for 72 h at 160 °C gives blue needle like crystals of [VIV
2O2(H2O)2(C6H2(COO)4)] in 30% yield. The compound has a porous 3-D extended network structure having a rigid architecture which is held together
by the multidentate functionalities of 1,2,4,5-benzenetetracarboxylate ligand. Crystal data for the compound: monoclinic space
group C 2/c (No:15), a = 11.756(5) ?, b = 9.645(3) ?, c = 11.822(7) ?, β = 107.10(4)°, Z = 8. The compound constitutes the first example of a fully reduced oxovanadium based solid incorporating the organic ligand.
This article consists of synthesis, crystal structure and characterization of [VIV
2O2(H2O)2(C6H2(COO)4)]. 相似文献
998.
Mehmet Kabak Yalçin Elerman Süheyla Özbey Orhan Atakol 《Journal of chemical crystallography》1995,25(5):259-262
The crystal and molecular structure of the title complex, C18H19N2OSNi, has been determined by direct methods. The compound crystallizes in monoclinic crystal system witha=11.968(1),b=12.182(1),c=12.399(1) Å, =115.23(1)°, space group P21/n. Nickel is in a slightly distorted square-planar environment of two nitrogens [1.881(2) and 1.952(2) Å] and one oxygen [1.856(3) Å] and one sulphur [2.138(2) Å] atom. Ni is 0.005 Å out of the plane of its ligands. 相似文献
999.
Admittance (Ym) versus applied gate bias (VG) on MIS structure (Cr/a-SiNx:H/p-Si) was measured as a function of frequency (mHz-MHz)/temperature (77-400 K) as parameters to investigate minority carrier behavior. Strong frequency dispersion in measured capacitance at inverting gate bias (positive biases for p-type silicon substrate) and low frequency behavior in capacitance-voltage (C-V) curves under high measuring frequencies (above kHz) at 300-400 K temperature interval are reported. This phenomenon is interpreted via lateral hopping conductivity of self-inversion charges beyond the gate inside a-SiNx:H film near interface as generation mechanism of minorities with a lower activation energy (0.11 eV) rather than prevailing mechanisms of much higher activation energies (namely, generation-recombination and diffusion). 相似文献
1000.
Yalçin Elerman Mehmet Kabak Ingrid Svoboda Hartmut Fuess Orhan Atakol 《Journal of chemical crystallography》1995,25(5):227-230
Tris-(2,2,2)-triaminoethylamino-salicylidene iron(III) crystallizes in the monoclinic crystal system witha=7.766(2),b=25.423(5),c=13.318(5) Å, =118.04(3)°, space group P21/c,V=2320.8(6) Å3,Z=4, andD
x=1.464 g cm–3. The center of the axially distorted octahedron is occupied by the Fe atom which is coordinated by six donor nitrogen and oxygen atoms infac positions. The planes of coordinated atoms (N and O) with the Fe(III) atom are almost planar and the maximum elevated atom from these planes is O(1) (–0.1065 Å). 相似文献