Wyniki wyszukiwania - BazTech

1

Effect of Sulfur and Acid Soluble Aluminum Content on Precipitate and Microstructure of Grain-Oriented Silicon Steel

Zhou B., Zhu C., Li G., Luo Z., Gao Y., Bao S., Schneider J.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 4

1701--1708

EN

The combined effect of sulfur (S) and acid soluble aluminum (Als ) content on precipitates and microstructures in grain-oriented silicon steel were investigated. The results show that there are dominant AlN and a little amount of MnS-AlN composite in annealed hot-rolled band, and the amount of precipitates increases distinctly with increasing Als content, while S content plays a negligible role. The inhibitors that precipitate during hot band annealing can restrain the grain growth during hot band annealing and primary annealing, and the smaller grains of annealed hot-rolled band can contribute to the formation of {111} <112> texture during primary annealing. Lower S content is conducive to the formation of {111} <112> texture during primary annealing by promoting the formation of Goss texture during hot rolling.

2

Rare Earth Elements supply vs. clean energy technologies: new problems to be solve

Zhou B., Li Z., Zhao Y., Zhang C., Wei Y.

Gospodarka Surowcami Mineralnymi

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2016

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T. 32, z. 4

29--44

EN

Rare earth elements (REEs) provide important properties to clean energy technologies such as wind turbine and hybrid electric vehicles. The global REE demand will grow rapidly during the global transformation toward a greener economy in the next decades. This high demand will require a steady supply chain in the long run. China has a monopoly of global REE production and extraction. The global REE supply chain runs the risk of disruption along with Chinese REE policy evolution. To overcome this supply chain vulnerability, new strategies and measures should be adopted to satisfy future REE supply/demand. There is a pressing need to explore REE deposits, develop efficient REE recycling techniques from end-of-life products, improve substitution technologies for REEs, and reduce the number of critical REEs used in devices. Such measures are facing significant challenges due to environmental factors and an unbalanced market, and overcoming them requires efforts from government and REE companies.

PL

Pierwiastki ziem rzadkich (Rare Earths Elements) mają istotne znaczenie dla rozwoju czystych technologii energetycznych, takich jak turbiny wiatrowe czy pojazdy hybrydowe. Światowy popyt na REE będzie wzrastał w związku z globalną transformacją w kierunku bardziej czystej (ekologicznej) gospodarki w okresie najbliższych dziesięcioleci. Wysoki popyt wymagać będzie stabilnego łańcucha dostaw REE w dłuższej perspektywie. Chiny mają monopol w zakresie globalnej produkcji i wydobycia REE. Światowe dostawy REE obarczone są jednak ryzykiem zakłóceń wynikających z chińskiej polityki w tym zakresie. W związku z tym, powinny być przyjęte nowe środki i strategie w celu zaspokojenia przyszłego popytu/podaży na REE. Istnieje pilna konieczność: poszukiwania nowych złóż, opracowania skutecznych technik recyklingu z wycofanych z eksploatacji produktów, poprawy technologii z zastosowaniem substytutów REE oraz zmniejszenie liczby krytycznych pierwiastków ziem rzadkich w stosowanych urządzeniach. Działania te stanowią poważne wyzwanie ze względu na czynniki środowiskowe i niezrównoważony rynek (monopol podaży). Przezwyciężenie ich wymaga odpowiednich działań ze strony rządu i firm zajmujących się produkcją REE.

3

Application of TVS in electrostatic protection for SCB initiators

Zhou B., Gang R., Li Y., Jia X., Wen L.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 8

133--136

EN

In an effort to avoid damages or unintentional firing of SCB initiators caused by ESD, three types of TVS chips are employed for electrostatic protection in this paper. The parameters and protection principles of TVS chips are analysed, and the appropriate TVS are selected to verify its ability for protecting SCB initiators from ESD. By electrostatic sensitivity experiments, the affection of TVS parameters on the electrostaticprotectioneffect is studied, the results show that the A type TVS chips can significantly protect SCB against static electricity, and the TVS chips with lower parasitic resistance and larger parasitic capacitance can enhance the anti-electrostatic capability of SCB initiators.

PL

W celu uniknięcia zniszczenia przez wypalenie inicjatora SCB sprawdzono trzy rodzaje zabezpieczeń TVS przed wyładowaniem elektrostatycznym. W wyniku eksperymentu stwierdzono że zabezpieczenie typu A chroni urządzenie przed wyładowaniem.

4

Speech Enhancement by Short-Time Spectrum Estimation with Multivariate Laplace Speech Model

Zhou B., Zhang X., Zou X., Zhao G.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 12a

338-342

EN

The paper presents a new short-time spectrum estimation algorithm for speech enhancement. A novel multivariate Laplace speech model is utilized to characterize the dependencies between adjacent DFT coefficients of speech, based on which a minimum mean-square error (MMSE) estimator of speech spectral components is derived. Moreover, the speech presence uncertainty is incorporated to modify the MMSE estimator. Experimental results show that the developed algorithm achieves better noise suppression and lower speech distortion compared to the existing speech enhancement methods.

PL

W artykule przedstawiono nowy algorytm estymacji krótkookresowego spektrum głosu do poprawy dźwięku mowy. Wykorzystano wieloczynnikowy model Laplace'a w celu scharakteryzowania zależności pomiędzy składnikami DFT dźwięku mowy. Na tej podstawie obliczane jest minimum błędu średnio-kwadratowego dla estymatora. Wyniki eksperymentalne potwierdzają ulepszoną skuteczność eliminacji zakłóceń mowy, w porównaniu ze stosowanymi metodami.

5

Research on Damage Mechanism of SCB Initiators under RF

Chen F., Zhou B., Qin Z, Shen R.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 11a

188-190

EN

In order to elucidate the response characteristic of semiconductor bridge(SCB) initiators under radio frequency(RF), RF measurement system was used to test the RF sensitivity of SCBs, after that the energy stored in a 22?F was used to activate the SCB. It is inferred from the results of Bruceton-method firing experiment that RF energy does not damage the SCB chip, but can lead to the accidental ignition of SCB initiators or change the color of normal lead styphnate(NLS). RF can also passivate SCB significantly and the all-fire voltage increases from 6.71V to 7.72V. The experimental data of X-ray photoelectron spectroscopy(XPS) analysis, directly indicated that heat generated by RF changes the valence of Pb in NLS from +2 to +4. The decomposition of NLS is responsible for the loss in sensitivity of SCBs. The research results provide a theoretical guidance for the electromagnetic compatibility(EMC) design of SCB initiators.

PL

W artykule opisano badanie oddziaływania sygnałów częstotliwości radiowej (ang. Radio Frequency) na zapalniki zbudowane z mostka półprzewodnikowego. Przedstawiono omówienie teoretyczne oraz wyniki badań eksperymentalnych.

6

Research on the Mechanism of Pin-to-Pin ESD to SCB Initiators

Chen F., Zhou B., Qin Z.

Przegląd Elektrotechniczny

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2011

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R. 87, nr 12a

169-172

EN

By ESD experiment, SEM-EDXA and firing experiment, the electrostatic-response characteristic of SCB was studied and the electrical explosion performance after ESD was measured. Results show that surface-damage of bridge is not obviously visible when lower than 25kV, but part of samples coated with explosive fire; the V-type angles start to be damaged at 25kV. After ESD, the function time and firing energy required decrease significantly. 25kV is the critical damage-voltage of the bridge. When less than 25kV, the electrical energy can only make the polysilicon melting and at 25kV, the temperature reaches the boiling point of silicon to generate plasma.

PL

Analizowano odpowiedź elektrostatyczną i parametry inicjatora eksplozji. Uszkodzenia mostka są nie zawsze widoczne jeśli napięcie jest poniżej 25 kV. Dlatego stwierdzono że napięcie 25 kV jest krytyczne, poniżej powoduje topienie polisilikonu, ale powyżej skutkuje tworzeniem się plazmy.

7

Effective stimulation of tight gas and shale reservoirs with microemulsions

Zelenev A., Zhou B., Penny G.

Prace Naukowe Instytutu Nafty i Gazu

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2010

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nr 170 wyd. konferencyjne

297--301

EN

Effective production from tight gas formations is associated with overcoming high capillary pressure existing in such reservoirs. The latter causes a leak-off of completion fluids into a formation and results in formation damage due to pore blockage and in situ formation of emulsions. Chemical treatment with microemulsions significantly remediates formation damage, increases fluid flowback, and enhances formation permeability to gas, which has been demonstrated both in laboratory and field studies.

8

Leading edge skewed-swept diagonal compressor rotor and numerical analysis on its internal flow mechanism

Zhou B., You B., Wu W., Wu K-Q.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2009

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Vol. 13, No 1-2

33-43

EN

The structure of each part of a diagonal compressor directly affects its overall performance and internal flow. We introduce the Reynolds-averaged Navier-Stokes flow simulation for unit calculation on the whole system including a diagonal impeller, a vaneless diffuser and a volute. By analyzing different flow chromatograms of specific sections, we can compare the configuration of three types of diffusers and volutes and the meridian flow status of the corresponding diagonal compressors which serves as a basis for the impeller flow path as well as for its matching designs. Considering the interference between the rotor and the upstream and downstream stillness body, this thesis analyzes how the vaneless diffuser meridian flow path, the volute flow path and its section secondary flow affect the upstream rotor flow. Both the calculation and experimental data on the rotor outlet are compared, as well as the calculated numerical value of the meridian plane streamline distribution and the diffuser velocity distribution, upstream and downstream, coincides with the designed numerical value. Without changing the conventional quasi-three-dimensional design system, the thesis applies the annulus wall boundary layer theory and the velocity distribution diagram to sweep and skew the leading edge of the airfoil. A performance test shows that the leading edge skewed-swept diagonal rotor can better improve the stall characteristic in a low flow rate area and expand the surge margin, compared with conventional diagonal rotor. It can also efficiently restrain the low-momentum fluid conglomeration near the wall region and reduce the secondary flow loss by sweeping and skewing the blade properly. The purpose of the thesis is to make a contribution to optimizing the overall structure design of diagonal compressors and to study further the complex internal flow between the leading edge skewed-swept diagonal rotor and the cover.