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91.
H-point standard addition method, HPSAM, with simultaneous addition of three analytes is proposed for the resolution of ternary mixtures. It is a modification of the previously described H-point standard addition method that permits the resolution of three species from a unique calibration set by making the simultaneous addition of the three analytes. The method calculates the analyte concentration from spectral data at two wavelengths where the two species selected as interferents present the same absorbance relationship. These wavelength pairs are easily found, and can be selected to give the most precise results. Diethyldithiocarbomate (DDC) in a cationic micellar solution of cetyltrimethylammonium bromide (CTAB) was used for determination of Fe(II), Co(II) and Cu(II) at pH 5.50. The results showed that simultaneous determination of Fe(II), Co(II) and Cu(II) could be preformed in the range of 0.0–6.0, 0.0–8.0 and 0.0–12.0 μg ml−1, respectively. The proposed method was successfully applied to the simultaneous determination of Fe(II), Co(II) and Cu(II) in several synthetic mixtures containing different concentration of Fe(II), Co(II) and Cu(II). 相似文献
92.
Titration calorimetry was used to construct the solid-liquid equilibrium line in ternary systems containing the solute and an aqueous mixed solvent by measuring the heat of dissolution of the solid solute during successive additions of the liquid solvent. The plot of cumulated heats versus the mole ratio, nsolvent/nsolute, yields two (almost) linear increases of different slopes. These two lines represent successively the enthalpy of dissolution then the enthalpy of dilution of the medium; their intersection gives the solubility and the enthalpy of dissolution of the solute. Phase diagrams have been established over the whole concentration range for o-anisaldehyde, 1,3,5-trimethoxybenzene and vanillin, in water + methanol, +ethanol, or +n-propanol at 303, 313 and 318 K. 相似文献
93.
According to the next-state equations of various ternary flip-flops(tri-flop),whichare based upon ternary modular algebra,various ternary flip-flops are implemented by usinguniversal-logic-modules,U_hs.Based on it,ternary sequential circuits are implemented by usingarray of universal-logic-modules,U_hs. 相似文献
94.
95.
用 pH电位滴定法测定了铂 (Ⅱ )与核苷酸NTP (NTP为腺苷 5′ 三磷酸和尿苷 5′ 三磷酸 )和另一芳环系列配体ArL形成的三元混配配合物Pt(ArL) (NTP) n -(ArL =Phen ,Bpy和Trp ;n =2或 3)在水溶液中的稳定常数 (I=0 .1mol/L ,KNO3 ;2 5℃ ) .用ΔlogKPt比较了二元和三元混配配合物的稳定性差异 ,认为三元混配配合物稳定性的增加可归因于π 酸与π 碱之间的合作效应和分子内芳环配体的堆积作用 相似文献
96.
R. Craigen 《Journal of Combinatorial Theory, Series A》2006,113(6):952-965
In [R. Craigen, C. Koukouvinos, A theory of ternary complementary pairs, J. Combin. Theory Ser. A 96 (2001) 358-375], we proposed a systematic approach to the theory of ternary complementary pairs (TCPs) and showed how all pairs known then could be constructed using a single elementary product, the natural equivalence relations, and a handful of pairs which we called primitive. We also introduced more new primitive pairs than could be inferred previously, concluding with some conjectures reflecting the patterns that were beginning to arise in light of the new approach.In this paper we take what appears to be the natural next step, by investigating these patterns among those lengths and weights that are within easy computational distance from the last length considered therein, length 14. We give complete results up to length 21, and partial results up to length 28. (Ironically, although we proceed analytically by weight first then length, for computational reasons we are bound, in this empirical investigation, to proceed according to length first.)Thus we provide support for the previous conjectures, and shed enough new light to speculate further as to the likely ultimate shape of the theory. Since short term work on TCPs will require massive acquisition of data about small pairs, we also discuss affixes—a computational strategy that arose out of the investigations culminating in this article. 相似文献
97.
S. P. Tretyakova Yu. E. Penionzhkevich H. -G. Ortlepp V. V. Trofimov Yu. V. Pyatkov Yu. M. Kulakov 《Radiation measurements》1997,28(1-6):303-304
Investigation of the 246Cm spontaneous ternary decay into nearly equal clusters using polyethyleneterephthalate track detectors has been carried out. The possibility of ternary cluster decay has been found out to be of less than 10−6 with respect to all fission modes of 246Cm. 相似文献
98.
We consider two analogues of associativity for ternary algebras: total and partial associativity. Using the corresponding ternary associators, we define ternary analogues of alternative and assosymmetric algebras. On any ternary algebra the alternating sum [a, b, c] = abc − acb − bac + bca + cab − cba (the ternary analogue of the Lie bracket) defines a structure of an anticommutative ternary algebra. We determine the polynomial identities of degree ?7 satisfied by this operation in totally and partially associative, alternative, and assosymmetric ternary algebras. These identities define varieties of ternary algebras which can be regarded as ternary analogues of Lie and Malcev algebras. Our methods involve computational linear algebra based on the representation theory of the symmetric group. 相似文献
99.
稀土与8-羟基喹啉三元配合物的合成研究Ⅱ.甲基丙烯酸稀土与8-羟基喹啉三元固态配合物的合成与表征王学智(安徽机电学院食品工程系芜湖241000)关键词稀土甲基丙烯酸8-羟基喹啉三元配合物Biryulina[1]首次报导了甲基丙烯酸稀土的合成与表征。8... 相似文献
100.
Ternary and quaternary fission produced in silver and bromine nuclei have been studied withK5 nuclear emulsion exposed to 1.8 GeV/cK
− beams. The frequency of the ternary events is found to be ∼0.08 of that of the binary events produced in the same volume
of the emulsion. The range ratio and range distribution of the fission fragments are studied and the angles between each pair
of the fragments are determined. Ranges are found to vary from 5 to 40μ with a maximum number lying between 5 and 10μ. The angles between the fission fragments are found to form a broad distribution extending from 40° to 180°. A few of the
events have also been analysed to give them a possible identity. A possible case of quaternary fission has also been reported.
This paper was presented at the Symposium on 3rd High Energy Physics held at Bhubaneswar during November 1976. 相似文献