Wyniki wyszukiwania - Biblioteka Nauki

1

A Multi-Level Inverter for Ultra High Speed PM Motor Control Application

100%

Xu L. , Li Y. , Zheng Z. , Ma H. , Wang K.

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2012

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tom R. 88, nr 5b

11-16

EN

The general concepts of multi-level technology involve utilizing a higher number of semiconductor devices to achieve higher power conversion, eliminate harmonics and reduce the switching loss. This paper is concerned with applying multi-level techniques to a PM motor to achieve ultra high speed features with better quality waveforms and less dv/dt for an aerospace application. A three-level diode clamped inverter is used to control a low inductance, ultra high speed PM motor with an integrated designed load compressor. Results from a 15kW experimental prototype are presented to validate the reliability of the inverter, the stability of the DC-link voltage balance and the practicality of vector control in this application.

PL

W artykule opisano zastosowanie wielopoziomowego przekształtnika do sterowania silnikiem z magnesami trwałymi. Osiągnięto bardzo dobra jakość kształtu sygnału napięciowego I małe dV/dt. Dzięki temu uzyskano ultra duża szybkość do zastosowań lotniczych

2

Studies on the Configuration and Structural Stability for Subnitrosyl Fe(NO)n (n = 1–4)

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Wang W. , Zhou Z. , Ma H. , Zhao S. , Chen J.

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2007

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tom Vol. 81, nr 4

573-589

EN

The structural properties and vibrationalmode of the transitionmetal Fe subnitrosyl complexes Fe(NO)n (n = 1–4) have been examined by using HF, B3LYP, B3P86 and B3PW91 methods at 6-311G basis set level. Results indicate that the interaction between Fe and NO should be characterized as a dative bond, in whichmonosynapic basin of the nitrogen plays the role of the disynapic basin connecting the metal core to the nitrogen atom. It shows that Fe(NO)n (n = 1–4) species have two states. Interestingly, for FeNO and Fe(NO)3 molecules, they are doublet (2 ) and quartet (4 ) states, while for Fe(NO)2 and Fe(NO)4 molecules, they are triplet ( 3 ) and quintet (5 ) states. The ground state of FeNO is of doublet (2 ) symmetry, but we have found that the two states of FeNO are very close in energy at different computational levels, and they are both belonging to Cv point group. For Fe(NO)2 species, the two states (3 and 5 ) have v-type structures (C2v point group) and linear structures (Dh point group). The same as FeNO species, the two states have similar energies. According to the analysis of the bond lengths, the ground state is the quintet (5 ) statewith a linear structure. In Fe(NO)3 species, the doublet(2 ) state and quartet (4 ) state are also close in energies, and they both have planar structures. The difference is that the doublet (2 ) state has a equilateral triangle structure, belonging to D3h point group, while the quartet (4 ) state has a isoceles triangle structure. The Fe(NO)4 species have a cube (Td point group) structure in the triplet (3 ) state and a similar cube structure in thequintet ( 5 ) state.Detailed bonding analysis has implied that the existence of the polynitrosyl Fe with more NOs and of other similar transition metal nitrosyl complexes is possible.

3

Sensitive fluorimetric determination of protein with dibromohydroxyphenylfluorone-molybdenum(VI) comlex probe based on fluorescence quenching in non-ionic microemulsion

86%

Wei Q. , Li Y. , Yan T. , Duan C. , Ma H. , Bin D.

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2006

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tom Vol. 51, No. 5

691-700

EN

In this paper binding interaction between a new fluorescence probe dibromohydroxyphenyi-fluoronc-molybdenum(VI) (DBHPF-Mo(Vl) and a protein has been studied. In the presence of the cmulsifier OP microemulsion of pH 3.2 DBHPF-Mo(VI) complex binds the protein rapidly to form a stable compound of a maximum excitation wavelength (λex) of 468 nm and a maximum emission wavelength (λcm) of 527 nm. Fluorescence intensity of the probe is quenched by the protein. The magnitude of quenching is linearly proportional to the protein concentration. Under optimum conditions calibration plots for bovine serum albumin (BSA), human serum albumin (USA), and ovalburnin (Ova) have been constructed in the concentration ranges of 0∼6.00 μg mL-1, 0∼4.00 μg mL-1 and 0∼4.00 -1 , respectively. Addition of the OP microemulsion to the system during protein determination has increased significantly the sensitivity of the analysis by changing the microenvi-ronment. The corresponding detection limits of BSA, HSA and Ova were 3.4 ng mL-1, 3.6 ng mL-1 and 6.2 ng mL-1 The developed procedure has been satisfactorily applied to the determination of protein in urine.

PL

Zbadano oddziaływanie nowego odczynnika fluorescencyjnego: dibromohydroksyfluoron-molibden(VJ) (DBHPF-Mo(VI) z białkiem, W obecności emulgatora OP, przy pH 3,2 mikroemulsja kompleksu DBHPF-Mo(Vl) wiąże szybko białko, tworząc trwale połączenie o długości fali promieniowania wzbudzającego 468 nm i emitowanego 527 nm. Intensywność fiuorescencj i jest tłumiona w obecności białka. Wielkość tłumienia jest liniowo proporcjonalna do stężenia białka. W optymalnych warunkach otrzymano wykresy kalibracyjne dla albuminy surowicy wołowej (BSA), albuminy surowicy ludzkiej (HSA) i owalbuminy (Ova) w zakresach odpowiednio: 0∼6.00 μg mL-1, 0∼4.00 μg mL-1. Dodatek emulgatora OP zwiększa znacznie czułość metody. Granice wykrywalności BSA. HSA i Ova wy noszą odpowiednio mL-1, 3.6 ng mL-1 and 6.2 ng mL-1 . Opracowaną procedurę zastosowano do oznaczania białka w moczu.

4

iTRAQ-based quantitative proteomics analysis reveals inhibitory mechanismsof the antimicrobial peptide MDAP-2 against Salmonella gallinarum

71%

Zhang Y. , Yu S. , Ying X. , Jia B. , Liu L. , Liu J. , Kong L. , Pei Z. , Ma H. , Zhang Y. , Yu S. , Ying X. , Jia B. , Liu L. , Liu J. , Kong L. , Pei Z. , Ma H.

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nr 3