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Four-step DOAS calibration method of SO_2 in flue gas

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Chinese Optics Letters 2009年第6期7卷 539-541页

作者：周涛刘斌孙长库 State Key Laboratory of Precision Measurement Technology and Instruments Tianjin University

SO2 monitoring in the flue gas of a coal burning boiler is important for environmental protection. The non- linearity of practical condition causes deviation from theoretical law. On the basis of the Lambert-Beer Law, a new four-step calibrntion method is introduced. This method includes cross section interpola- tion, weighting spectral region combination, acquiring the spectrum with new calibration devices, and least-square fitting. Compared with conventional methods, this new method is low cost, convenient, and accurate. In the proof test, SO2 samples with different concentrations are measured. The average errors are less than 1.5%, while the maximum deviation is less than 4.5%.

关键词： Beverages Calibration Flue gases

Closed-loop dynamic control allocation for aircraft with multiple actuators

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Chinese Journal of Aeronautics 2013年第3期26卷 676-686页

作者： Gai Wendong Wang Honglun Science and Technology on Aircraft Control Laboratory Beihang University

A closed-loop control allocation method is proposed for a class of aircraft with multiple actuators. Nonlinear dynamic inversion is used to design the baseline attitude controller and derive the desired moment increment. And a feedback loop for the moment increment produced by the deflections of actuators is added to the angular rate loop, then the error between the desired and actual moment increment is the input of the dynamic control allocation. Subsequently, the stability of the closed-loop dynamic control allocation system is analyzed in detail. Especially, the closedloop system stability is also analyzed in the presence of two types of actuator failures： loss of effectiveness and lock-in-place actuator failures, where a fault detection subsystem to identify the actuator failures is absent. Finally, the proposed method is applied to a canard rotor/wing （CRW） aircraft model in fixed-wing mode, which has multiple actuators for flight control. The nonlinear simulation demonstrates that this method can guarantee the stability and tracking performance whether the actuators are healthy or fail.

关键词： Canard rotor/wing aircraft Closed-loop control allocation Dynamic inversion Flight control systems Redundant actuators

Research of Compound Controller for Flight Simulator with Disturbance Observer

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Chinese Journal of Aeronautics 2011年第5期24卷 613-621页

作者： WU Yunjie LIU Xiaodong TIAN Dapeng Science and Technology on Aircraft Control Laboratory School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China

A compound controller is proposed to alleviate the considerable chattering in output of zero phase error tracking controller （ZPETC）, when the flight simulator losses command data of simulation signal. Besides, the shortcomings, caused by conventional differential methods in retrieving velocity and acceleration signals, are avoided to a certain extent. The compound controller based on disturbance observer （DOB） is composed of a feed-forward controller and a feedback controller. It estimates velocity and acceleration of unknown tracking signal, and also velocity response with an approximate method for differential. The experiments on a single-axis flight simulator show that the proposed method has strong robustness against parameter perturbations and external disturbances, owing to the introduced DOB. Compared with the scheme with ZPETC, the proposed scheme possesses more simple design and better tracking performance. Moreover, it is less sensitive to position command distortion of flight simulator.

关键词： compound controller zero phase error tracking controller flight simulators disturbance observer robustness

Mechanism of zinc damaging to blast furnace tuyere refractory

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Acta Metallurgica Sinica(English Letters) 2009年第6期22卷 454-460页

作者： Xuefeng FANG Mansheng CHU Fengman SHEN Zhuming ZHANG school of Minerals Processing and Bio-engineering Central South University Changsha 410083 China Technology Center Kunming Iron and Steel Limited Company Kunming 650302 China School of Materials and Metallurgy Northeastern University Shenyang 110004 China

The phenomena of tuyere upward-warp have been found at No.6 blast furnace in Kunming Steel Company China after its blow-in, which has made a great impact on the practical production of the furnace. Thus, a number of efforts have been made to elucidate the mechanism of this phenomenon. The results of investigation and tests revealed that the enrichment and expansion of zinc in the tuyere bricks is the main factor leading to the tuyere upward-warp. The eroding behavior of zinc is that the inner structure of the tuyere bricks turns from dense to loose with entering, enriching and expanding of zinc, which forms spot-like→stripe-like→ditch-like→vein-like→tumorlike eroding passage. Additionally, it is found that the sequence of deleterious ele- ments entering the tuyere refractory is K, Na, Zn and Pb, respectively. Finally, the phenomena and process of zinc crystallization and growth in the refractory have been clearly observed and recorded during this investigation.

关键词： Blast furnace Tuyere Refractory Zinc Erosion Deleterious elements

Impact of KRAS mutation and PTEN expression on cetuximab-treated colorectal cancer

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World Journal of Gastroenterology 2010年第46期16卷 5881-5888页

作者： Fang-Hua Li,Zhuang-Hua Li,Hui-Yan Luo,Miao-Zhen Qiu,Yu-Hong Li,Rui-Hua Xu,State Key Laboratory of Oncology in Southern China,Department of Medical Oncology,Sun YatSen university Cancer Center,Guangzhou 510060,Guangdong Province,China Fang-Hua Li,Department of Medical Oncology,Shengli Oil Field Central Hospital,Dongying 257034,Shandong Province,China Lin Shen,Department of GI Oncology,Peking university School of Oncology,Beijing Cancer Hospital and Institute,Beijing 100142,China Hui-Zhong Zhang,State Key Laboratory of Oncology in Southern China,Department of Pathology,Sun Yat-Sen university Cancer Center,Guangzhou 510060,Guangdong Province,China State Key Laboratory of Oncology in Southern China Department of Medical Oncology Sun Yat-Sen University Cancer Center Guangzhou 510060 Guangdong Province China. xurh@***

AIM:To investigate the prognostic value of KRAS mutation,and phosphatase and tensin (PTEN) expression in Chinese metastatic colorectal cancer metastatic colorectal cancer (mCRC) patients treated with ***:Ninety Chinese mCRC patients treated with cetuximab were evaluated for KRAS mutation and PTEN protein expression by DNA sequencing of codons 12 and 13 and immunohistochemistry,*** then selected 61 patients treated with cetuximab,either in combination with chemotherapy,or alone as a second-line or third-line regimen to assess whether KRAS mutation or PTEN protein expression is associated with the response and the survival time of mCRC patients treated with ***:KRAS mutation was found in 30 (33.3%) tumor samples from the 90 patients,and positive PTEN expression was detected in 58 (64.4%) of the 90 *** the 61 patients who were treated with cetuximab as a second-line or third-line regimen,the resistance to cetuximab was found in 22 patients with KRAS mutation and in 39 patients without KRAS mutation,with a response rate of 4.5% and 46.1% respectively (P=0.001),a shorter median progression-free survival (PFS) time of 14 ± 1.3 wk and 32 ± 2.5 wk respectively (P < 0.001),a median overall survival (OS) time of 11 ± 1.2 mo and 19 ± 1.8 mo respectively (P < 0.001),as well as in 24 patients with negative PTEN expression and in 37 patients with positive PTEN expression respectively (P < 0.001),with a responsive rate of 4.2% and 48.6% respectively,a shorter median PFS survival time of 17 ± 2.0 wk and 28 ± 1.9 wk respectively (P=0.07),and a median OS time of 11 ± 1.3 mo and 18 ± 1.9 mo respectively (P=0.004).Combined KRAS mutation and PTEN expression analysis showed that the PFS and OS time of patients with two favorable prognostic factors were longer than those of patients with one favorable prognostic factor or no favorable prognostic factor (P < 0.001).CONCLUSION:KRAS mutation and PTEN protein expression are significantly corr

关键词： Cetuximab Metastatic colorectal cancer KRAS mutation Phosphatase and tensin protein expression

Design and simulation of digital channelized receivers in fractional Fourier domain

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Journal of Systems Engineering and Electronics 2013年第1期24卷 36-43页

作者： Pengfei Tang Bin Yuan Qinglong Bao Zengping Chen ATR Key Lab School of Electronic Science and EngineeringNational University of Defense Technology

An approach is proposed to realize a digital channelized receiver in the fractional Fourier domain （FRFD） for signal intercept applications. The presented architecture can be considered as a generalization of that in the traditional Fourier domain. Since the linear frequency modulation （LFM） signal has a good energy concentration in the FRFD, by choosing an appropriate fractional Fourier transform （FRFT） order, the presented architecture can concentrate the broadband LFM signal into only one sub-channel and that will prevent it from crossing several sub-channels. Thus the performance of the signal detection and parameter estimation after the sub-channel output will be improved significantly. The computational complexity is reduced enormously due to the implementation of the polyphase filter bank decomposition, thus the proposed architecture can be realized as efficiently as in the Fourier domain. The related simulation results are presented to verify the validity of the theories and methods involved in this paper.

关键词： digital channelized receiver fractional Fourier domain(FRFD) convolution theorem sampling theorem.

Preparation of Functional Gradient Material n-PbTe with Continuous Carrier Concentration

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Chinese Physics Letters 2010年第5期27卷 250-252页

作者：朱品文洪友良王欣陈立学今井义雄 State Key Lab for Superhard Materials Jilin University Changchun 130012 National Institute for Materials Science Tsukuba 305-0047 Japan

Functional gradient materials （FGMs） in thermoelectric materials can raise the maximal power output of the thermoelectric generator （TEG）. We report an FGM of n-PbTe with continuous carrier concentration successfully prepared by a unidirectional solidification method. The continuous carrier concentration for n-Pb Te was optimized by different dopants of PbI2, Al and Zr and solidifying temperature. The effective maximum outputting power for continuous FGM PbTe is about 30% larger than that for jointed FGM PbTe.

关键词： FUNCTIONALLY gradient materials LEAD telluride crystals THERMOPHYSICAL properties MATERIALS -- Electric properties SOLIDIFICATION TEMPERATURE effect

Ambient noise spectral properties in the north area of Xisha

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Acta Oceanologica Sinica 2014年第12期33卷 206-211页

作者： DA Lianglong WANG Chao HAN Mei ZHANG Lin Navy Submarine Academy Naval Underwater Battlefield Environment Institution

Ambient noise is very important in the prediction system of a sonar performance, because it determines the detection ranges always in a passive sonar and usually in an active sonar. In the uncertainty issue for the so-nar performance, it is necessary to know this factor＇s statistical characteristics that are only obtained by data processing from the underwater ambient noise measurements. Broad-band ambient noise signals from 16 hydrophones were amplified and recorded for 2 min every 1 h. The results show that the ambient noise is essentially depth independent. The cross correlation of the ambient noise levels （1, 6 and 12 h average） with a wind speed is presented. It was found that the correlation is excellent on the upper frequency band and the noise levels correlate better with high wind speed than with low wind speed.

关键词： ambient noise cross correlation wind speed

Facile preparation of bi-functional iron doped mesoporous materials and their application in the cycloaddition of CO2

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Journal of Energy Chemistry 2020年第2期29卷 52-59页

作者： Dan Liu Gang Li Hongchen Guo Jiaxu Liu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian J16024LiaoningChina

Two kinds of bi-functional transition metal doped mesoporous materials(Fe-HMS and Fe-MCM-41) are prepared using one-step hydrothermal method and then treated with hydrochloric acid ethanol *** N2 adsorption and HRTEM results show that both of Fe-HMS and Fe-MCM-41 possess mesoporous structure. The UV–vis results suggest that the Fe species are mainly located within the framework. The basicity of as-prepared samples was studied by temperature programmed desorption using CO2 as probe molecule(CO2-TPD). The catalytic performance of Fe-HMS and Fe-MCM-41 in CO2 cycloaddition largely depends on the amount of the accessible basic sites. The acid–base active sites, framework Fe and PDDA species cooperatively catalyze the CO2 cycloaddition for the production of cyclic carbonates under the condition without any co-catalyst. The conversion of epichlorohydrin(ECH) is 97.4% and the selectivity of chloropropene carbonate is 92.9% under optimal conditions. The approximate rate constant of cycloaddition reaction of CO2 with ECH under optimum reaction temperature is calculated. It is worth noting that the Fe-HMS material shows superior reusability than Fe-MCM-41. In addition, this work provides a facile way on the synthesis of bi-functional acid–base heterogeneous catalyst with outstanding catalytic performance for the fixation of CO2.

关键词： Mesoporous material Cationic polymers Acid-base catalyst Cycloaddition reaction Cyclic carbonate