Wyniki wyszukiwania - BazTech

1

Enhancing SO2 removal efficiency by lime modified with sewage sludge in a novel integrated desulfurization process

Qin L., Han J., Chen W., Liu Z., He M., Xing F.

Environment Protection Engineering

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2017

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Vol. 43, nr 4

17--27

EN

In China, the sintering process annually emitted around 1.5 million t SO2, representing 70% of SO2 produced from the iron and steel industry. Lime based sorbent was modified with municipal sewage sludge (MSS) and the influence of the modification on the desulfurization efficiency was investigated in a laboratory-scale novel integrated desulfurization (NID) reactor. The properties of modified sorbent were characterized by the Brunauer–Emmett–Teller (BET) analyzer and X-ray fluorescence (XRD) analyzer. BET surface area was increased from 17.48 to 46.68 m2g–1. when the MSS/lime ratio increased from 0 to 0.08. Ca4Al8Si8O32, Ca1.5SiO3.5, Na2Si2O5 and CaSiO3 found in the modified lime benefited for the increase of the BET surface area and pore volume. The effects of sewage sludge/CaO weight ratio, calcination temperature and hydration time on the desulfurization efficiency were also studied. SO2 removal efficiency was increased from 88.7% to 97.3% after using the lime modified with sewage sludge.

2

Tree-Ring Response to Snow Cover and Reconstruction of Century annual Maximum Snow Depth for Northern Tianshan Mountains, China

Qin L., Yuan Y., Zhang R., Wei W., Yu S., Fan Z., Chen F., Zhang T., Shang H.

Geochronometria

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2016

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Vol. 43, no. 1

9--17

EN

Heavy snowfall and extreme snow depth cause serious losses of human life and property in the northern Tianshan Mountains almost every winter. Snow cover is an important indicator of climate change. In this study, we developed five tree-ring-width chronologies of Schrenk spruce (Picea schrenkiana Fisch. et Mey) from the northern Tianshan Mountains using standard dendrochronological methods. Correlation analyses indicated that radial growth of trees in the northern Tianshan Mountains is positively affected by annual maximum snow depth. This relationship was validated and models of annual maximum snow depth back to the 18th century were developed. The reconstruction explains 48.3% of the variance in the instrumental temperature records during the 1958/59–2003/04 calibration periods. It indicates that quasi-periodic changes exist on 2.0–4.0-yr, 5.3-yr, 14.0-yr, and 36.0-yr scales. The reconstructed series shows that maximum snow depth exhibits obvious stages change, the periods characterized by lower maximum snow depth were 1809/10–1840/41, 1873/74– 1893/94, 1909/10–1929/30, 1964/65–1981/82, and the periods characterized by higher maximum snow depth were 1841/42–1872/73, 1894/95–1908/09, 1930/31–1963/64, and 1982/83–present. The lower period of annual maximum snow depth during the 1920s–1930s is consistent with the severe drought that occurred at this time in northern China. From the 1970s to the present, the maximum snow depth has increased clearly with the change to a warmer and wetter climate in Xinjiang. The reconstruction sheds new light on snow cover variability and change in a region where the climate history for the past several centuries is poorly understood.

3

Investigation of HFC-134a decomposition by combustion and its kinetic characteristics in a laboratory scale reactor

Mi T., Han J., He X., Qin L.

Environment Protection Engineering

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2015

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Vol. 41, nr 4

143--150

EN

Thermal decomposition of HFC-134a at 900–1000 K was investigated using a laboratory scale reactor. The experimental results indicate that the lower initial HFC-134a concentration and higher reaction temperature could enhance HFC-134a decomposition efficiency. Based on the results of measurements, it seems that the reaction order is around 1. Its activation energy (Ea) and the frequency factor (A) in the investigated temperature range are 300.5 kJ·mol–1 and 2.96×1014, respectively. The results demonstrate that 99.9% destruction efficiency could be achieved when HFC-134a/LPG is below 0.5 and the excess air ratio – above 0.6.

4

Tree-ring based temperature reconstruction for the west Qinling Mountains (China): linkages to the High Asia, solar activity and Pacific-Atlantic Ocean

Chen F., Yuan Y., Wei W., Yu S., Shang H., Zhang T., Zhang R., Wang H., Qin L.

Geochronometria

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2014

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Vol. 41, no. 3

234--244

EN

We developed a Faxon fir (Abies faxoniana) tree-ring width chronology at the timberline in the western Qinling Mountains, China. Herein February–July mean temperature was reconstructed for Zhouqu in the western Qinling Mountains back to AD 1650 based on the standard chronology. The climate/tree-growth model accounts for 43.5% of the instrumental temperature variance during the period 1972–2006. Spatial correlation analyses with the gridded temperature data shows that the tem-perature reconstruction captures regional climatic variations over central and southeast China, and strong teleconnections with the nearby High Asia. There is a good agreement with cold and warm pe-riods previously estimated from tree-rings in Nepal, India and southwest China. The temperature re-construction indicates that there was pronounced cooling in Zhouqu during the Maunder Minimum (late 1600s to early 1700s). The cold period (1813–1827) of the temperature reconstruction coincide with the volcanic eruptions. Significant spectral peaks are found at 56.9, 22.3, 11.4, 2.9, 2.8, 2.6, 2.2 and 2.0 years. The spatial correlation patterns between our temperature reconstruction and SSTs of the Atlantic and Pacific Oceans suggest a connection between regional temperature variations and the atmospheric circulations. It is thus revealed that the chronology has enough potential to reconstruct the climatic variability further into the past.

5

Decision Prediction Using Visual Patterns

Qin L., Zhong N., Lu S., Li M.

Fundamenta Informaticae

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2013

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Vol. 127, nr 1-4

545--560

EN

Lack of understanding of users' underlying decision making process results in the bottleneck of EB-HCI (eye movement-based human-computer interaction) systems. Meanwhile, considerable findings on visual features of decision making have been derived from cognitive researches over past few years. A promising method of decision prediction in EB-HCI systems is presented in this article, which is inspired by the looking behavior when a user makes a decision. As two features of visual decision making, gaze bias and pupil dilation are considered into judging intensions. This method combines the history of eye movements to a given interface and the visual traits of users. Hence, it improves the prediction performance in a more natural and objective way. We apply the method to an either-or choice making task on the commercial Web pages to test its effectiveness. Although the result shows a good performance only of gaze bias but not of pupil dilation to predict a decision, it proves that hiring the visual traits of users is an effective approach to improve the performance of automatic triggering in EB-HCI systems.

6

Ta-doped In2O3 transparent conductive films with high transmittance and low resistance

Wang B., Hu L. M., Liu F. M., Qin L., Liu Y., Wang L. J.

Optica Applicata

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2010

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Vol. 40, nr 1

25--31

EN

Ta-doped In2O3 transparent conductive oxide (TCO) thin films are deposited on glass substrates by radio-frequency (RF) sputtering at room-temperature. The influence of sputtering power on the structural, morphologic, electrical, and optical properties of the films is investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Hall measurement, and optical transmission spectroscopy. The obtained films are polycrystalline with a cubic structure and preferentially oriented in the (222) crystallographic direction. The minimum resistivity of 2.8×10-4 ?cm is obtained from the film deposited at the sputtering power of 170 W. The average optical transmittance of the films is over 90%.