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1

Research on the influence of performance parameters on the super high speed permanent magnet synchronous generator external characteristic

Qiu H., Tang B., Yang C., Cui G.

Archives of Electrical Engineering

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2018

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Vol. 67, nr 1

179--192

EN

Super high speed permanent magnet generators (SHSPMG) usually operate at high frequency. The external characteristic of the SHSPMG under condition of high frequency operation is quite different from that of conventional generators. Therefore, it is necessary to study the external characteristic of the SHSPMG. Based on the finite element method, this paper studied the factors that affect the external characteristic of the SHSPMG. Combining the vector method and the finite element method, the external characteristic of the SHSPMG with the inductive load and the resistance load was studied. The variation law of the generator terminal voltage with the change of the load and current was obtained, and the key factors affecting the external characteristic of the SHSPMG were determined. The influences of the armature resistance, power factor, frequency and permanent magnet performance on the external characteristic of the SHSPMG were studied. The influence mechanism of different parameters on the generator external characteristic was revealed. The influence degree of each factor on the voltage regulation was determined. The conclusions can provide reference for the design and research of the SHSPMG.

2

Preparation and characterization of (Co0:3Zn0:7)(Ti1–xSnx)Nb2O8 microwave dielectric ceramics

Tang B., Zhang X., Fang Z., Liu Q., Zhang S.

Materials Science Poland

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2017

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Vol. 35, No. 2

405--411

EN

Zn0.7Co0.3 (Ti1-xSnx)Nb2O8 (x = 0.1, 0.15, 0.2, 0.25, 0.3, 0.35) microwave ceramics were prepared by traditional solidstate reaction method. The influences of Sn substituted for Ti on the phase constitution, crystal structure and microwave dielectric properties of Zn0.7Co0.3 (Ti1-xSnx)Nb2O8 ceramics were discussed. The XRD patterns revealed the main phase of ZnTiNb2O8 and little content of Zn0.17Ti0.5Nb0.33O2 secondary phase. With further substitution of Sn, the lattice constant, volume and apparent density of the ceramics increased, the ceramic structure reached a maximal compactness at x = 0.2 which was shown on SEM. Tremendous improvement of Q × f and a declining trend of Ɛr and τf were obtained with increasing x value. Appropriate substitution value (x = 0.10) would ensure excellent microwave dielectric properties (Ɛr = 34.1, Q × f = 40562 GHz, τf =-5 ppm/°C) of the ceramics sintered at 1080 °C.

3

Preparation and properties of low temperature sintered CaO-B2O3-SiO2 microwave dielectric ceramics using the solid-state reaction

Zhou X., Li E., Yang S., Li B., Tang B., Yuan Y., Zhang S.

Materials Science Poland

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2013

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Vol. 31, No. 3

404--409

EN

The LTCC CaO–B2O3–SiO2 (CBS) ceramics were synthesized via solid-state reaction process without any sintering aid. The effects of different sintering temperatures and B2O3 content on the microwave and mechanical properties were investigated. The results show that the best sintering temperature is around 950 °C and increasing amount of B2O3 promotes the crystallization of CaB2O4 enhancing the flexure strength of the CBS ceramics. However, the dielectric and mechanical properties deteriorated rapidly while the amount of B2O3 exceeded 25 wt.%. The sample with 20.5 wt.% B2O3 sintered at 950 °C had the best properties with er = 6.06; tand = 0.0015 (1 MHz) and a high flexure strength qf > 180 MPa.

4

Fast and sensitive spectrofluorimetric determination of trace amount of Pb(II) in sludge using o-vanilin-8-aminoquinoline

Tang B., Yue T., Wu J., Ding Y., Dong Y., Wang H.

Chemia Analityczna

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2005

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Vol. 50, No. 3

631-639

EN

o-Vanillin-8-am inoqu incline (OVAQ) — a novel fluorescent reagent has been synthesised and applied to the determination of Pb(II). In ethanol-water medium of pH 9.00 Pb(ll) reacted with OVAQ (&lambdaex/em= 278/318 nm) to form a 1; 1 non-fluorescent complex. Fluorescence quenching was proportional to the concentration of Pb(ll) in the range from 5.3 to 180 &mug L-1. Detection limit was 1.6 μg L-1. Interfering effect of 25 foreign ions on the determination results were studied. The method was successively applied to the determination of lead in sludge.

PL

Zsyntetyzowano nowy odczynnik fiuorymetryczny o-wanilino-8-aminochinolinę (OVAQ) 1 wyznaczono jego stale dysocjacji kwasowej. Zbadano reakcję fluorescencji odczynnika w obecności jonów oiowiu. W wodno-etanolowym roztworze o pH 9.0 Pb(II) reaguje 2 fluoryzującym (&lambdaex/em= 278/318 nm) odczynnikiem tworząc nie fluoryzujący kompleks o składzie 1:1. Wyznaczono liniowy zakres wykresu analitycznego od 5,3 do 180 μg -1 i granicę wykrywalności wynoszącą 1,6 μg L-1. Badano interferencje 25 jonów. Metoda jest prosta i została z powodzeniem zastosowana do oznaczania ołowiu w osadach.

5

Study and Application of HRP-like Catalyst Copper 2-Hydroxy-1-naphthaldehyde-2-aminothiazole {Cu II-(HNATS)2]

Tang B., Yue T. X., Du M., Wang Y., Chen Z. Z., Wang H. J.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 11

1527-1535

EN

2-Hydroxy-1-naphthaldehyde-2-aminothiazole (HNATS) and its copper complex [CuII-(HNATS)2] had been synthesized. The complex of [CuII-(HNATS)2] was used to mimic the active group of horseradish peroxidase (HRP). The catalytic characteristics of this HRP-like catalyst in the H2O2-phenol- 4-AAP redox coupling reaction was studied, and the catalytic activity of [CuII-(HNATS)2] was compared with those of HRP and other Schiff base metal complexes. It was found that [CuII-(HNATS)2] exhibits a good catalytic activity and could be used as a novel catalyst in the determination of hydrogen peroxide (H2O2). The reaction mechanism, optimal experimental conditions and interferences of coexisting substances were discussed. Under the experimental conditions established, the linear relationship between the absorbance at 504 nm (A504) and H2O2 concentration was in the range of 5.6×10-6~1.1×10-4 mol/L, with a correlation coefficient (r) of 0.9990. The linear regression equation was A504 = 2540×C (mol/L) - 3.0×10-3 with a detection limit of 1.7×10-6 mol/L. In this paper, the complex [CuII-(HNATS)2] was applied successfully with catalytic spectrophotometric method to the determination of (-O-O-H) in polyethylene glycol.