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Preparation and microstructure of CuO-CoO-MnO/SiO2 nanocomposite aerogels and xerogels as catalyst carriers

Progress in Natural Science:Materials International 2011年第4期21卷 330-335页

作者： Yue-qing ZHAO~1,Ying-hua LIANG~2,Xi-zhe ZHAO~3,Qian-yi JIA~4,Hong-sheng LI~4 1.college of Light Industry,Hebei United University,Tangshan 063000,china 2.college of Chemical engineering,Hebei United University,Tangshan 063009,china 3.college of Printing and Packaging engineering,Beijing institute of Graphic Communication,Beijing 102600,china 4.college of Materials Science and engineering,Hebei United University,Tangshan 063009,china [a] college of Light Industry Hebei United University Tangshan 063000 China [b] college of Chemical engineering Hebei United University Tangshan 063009 China [c] college of Printing and Packaging engineering Beijing Institute of Graphic Communication Beijing 102600 China [d] college of Materials Science and engineering Hebei United University Tangshan 063009 China

CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were prepared using tetraethyl orthosilicate（TEOS） as Si source,and aqueous solution of Cu,Co and Mn acetates as the precursor via sol-gel process,CO2supercritical drying（SCD） technique or ambient pressure drying *** microstructure of the CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were characterized by field emission scanning electron microscopy（FE-SEM）,transmission electron microscopy（TEM） and X-ray diffraction（XRD）.The specific surface area,pore size and pore size distribution of the nanocomposite aerogels and xerogels were determined by the Brunauer-Emmett-Teller（BET） *** results showed that CuO-CoO-MnO/SiO2nanocomposite aerogels are porous,with a pore size distribution of 2-50 nm,an average pore size of 19.4 nm,a specific surface area of 384.9 m2/g and a particle size distribution of 10-150 nm,whereas the pore size distribution of CuO-CoO-MnO/SiO2composite xerogels is 1.7-128.6 nm,the average pore size is only 9.9 nm,the specific surface area is only 99.1 m2/g,and the particle size distribution is 100-500 *** structure of CuO-CoO-MnO/SiO2nanocomposite aerogels is favorable to increase the loading of catalysts.

关键词： composite aerogel composite xerogel catalyst carrier preparation microstructure

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Pulmonary embolism and deep venous thrombosis in china

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Journal of Geriatric Cardiology 2024年第8期21卷 775-778页

作者： Sheng-Shou HU the Writing Committee of the Report on Cardiovascular Health and Diseases in china Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina 不详

The Annual Report on Cardiovascular Health and Diseases in china(2022) intricate landscape of cardiovascular health in *** connection with the previous section,this eighth section of the report offers a comprehensive analysis of pulmonary embolism and deep venous *** recent years,research in the field of pulmonary vessel in china has made great progress.A number of nationwide multi-center registry research results have filled the gaps in the epidemiology,diagnosis and treatment of pulmonary hypertension and venous *** types of pulmonary hypertension still need attention to the identification of risk factors and/or risk stratification,and venous thromboembolism needs attention in the prevention and the overall management inside and outside *** the future,we look forward to the publication of more high-quality research in china,which could be able to improve relevant guidelines for pulmonary vascular diseases both domestically and inter-nationally.

关键词： epidemiology prevention diagnosis

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Description to wear debris boundaries by radar graph fractal method

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Chinese Science Bulletin 2007年第16期52卷 2285-2290页

作者： LIU HongTao1,2 & GE ShiRong1 1 institute of Tribology and Reliability engineering,china University of Mining & technology,Xuzhou 221008,china 2 college of Mechanical and Electrical engineering,china University of Mining & technology,Xuzhou 221116,china institute of Tribology and Reliability engineering China University of Mining and Technology Xuzhou 221008 China

In this paper,radar graph fractal method is introduced to describe wear debris boundaries. Research results show that it is a nice way to describe wear debris boundaries. Since the longest axis is selected as the first coordinate axis,its center point selected as the center point of the radar graph,and the co-ordinate value of wear debris boundary selected as the measure parameter,the limitations existing in Yard fractal measure method can be avoided. For any wear debris,its radar graph fractal dimension value is one and only,and as the wear debris shape changes from round to strip,the radar graph fractal dimension value also changes from low to high,showing strong uniqueness and independence. Due to the fact that the researched wear debris is gotten in different wear states,the results also prove that radar graph fractal dimension value is correlated with frictional pairs work condition and wear state. Radar graph fractal method is compared with Yard fractal measure methods,and results show that ra-dar graph fractal dimension values gotten from different wear debris have enough value grads to avoid effect of errors,and provide higher sensitivity for wear debris shape. This paper also discusses the influencing factors for radar graph fractal method. With the increase of the decomposing degree value,the radar graph fractal dimension tends to keep stable at one certain value,showing the typical characteristic of the fractal theory. All this proves that radar graph fractal method is an effective description method for wear debris boundaries.

关键词：磨粒边界雷达图表分形法

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One-pot synthesis of crystalline SnO_2 nanoparticles and their low-temperature ethanol sensing characteristics

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1601-1605页

作者： CHEN YuJin1,2,3,ZHU ChunLing4,WANG LiJiao3 & WANG TaiHong2 1 School of Materials Science and engineering,Beijing institute of technology,Beijing 100081,china 2 Micro-Nano Technologies Research Center,Hunan University,Changsha 410082,china 3 college of Science,Harbin engineering University,Harbin 150001,china 4 college of Material Science and Chemical engineering,Harbin engineering University,Harbin 150001,china School of Materials Science and engineering Beijing Institute of Technology Beijing 100081 China Micro-Nano Technologies Research Center Hunan University Changsha 410082 China college of Science Harbin Engineering University Harbin 150001 China college of Material Science and Chemical engineering Harbin Engineering University Harbin 150001 China

Crystalline SnO2 nanoparticles(NPs) with a diameter less than 6 nm are synthesized using potassium stannate trihydrate as the precursor in a basic *** synthesized NPs can detect ethanol at a ppm level even at 100℃.Furthermore,the NPs have good selectivity to *** excellent ethanol sensing performances are attributed to the small size effect according to the space-charge model.

关键词： SnO2 nanoparticles sensing characteristics

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Investigation of 'chazi'(damaged-enamels)on Chenghua doucai Porcelains

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Science china(Technological Sciences) 2009年第6期52卷 1722-1729页

作者： DU Feng1 & SU BaoRu2 1 institute of Chemistry & Molecular engineering,Qingdao University of Science & technology,Qingdao,china 2 college of Information Science & technology,Qingdao University of Science & technology,Qingdao,china institute of Chemistry & Molecular engineering Qingdao University of Science & Technology Qingdao China college of Information Science & technology Qingdao University of Science & Technology Qingdao China

At the end of the 1950s,Sun Yingzhou considered that the 'chazi'(damaged colour)on Chenghua doucai imperial porcelain as a defect was originally produced in firing process during Chenghua period(1465―1487).Researchers in china have accepted his *** any fragment with the 'chazi' has never been found in several tons of Chenghua imperial sherds excavated from Ming imperial kiln site in *** china,few scholars have questioned the formation of 'chazi',and further investigated *** researchers at the Research Laboratory in the British Museum,employing unde-structive EDXRF,have analyzed the chemical composition of the 'chazi'(damaged colour)on a Chen-ghua doucai stem cup in the museum,and they have confirmed that the 'chazi'(damaged colour)was caused by the fire of the Jianfu palace in the Forbidden City in *** on their research,the authors studied the colour chemical principle of the 'chazi's' formation *** to the ceramic technology principle,scientific reasoning for the 'chazi' was carried *** the help of the history of Qing court,the brainteaser of the 'chazi' was totally uncovered,the misunderstanding for the 'chazi' has also been *** research also suggests that employing modern science and technology is a direction to study Chinese ancient ceramic further.

关键词： Chenghua doucai porcelains court eunuchs the set on fire at the Jianfu palace ’chazi’(damaged-enamels) the British Museum colour chemical principle archaeology using science and technology

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INFLUENCE OF TRACES OF WATER ON THE SYNTHESIS AND ELECTROLUMINESCENCE PROPERTIES OF POLY(2-METHOXY, 5- (2' -ETHYLHEXYL OXY)- 1, 4-PHENYLENE VINYLENE)

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Chinese Journal of Polymer Science 2002年第5期20卷 461-465页

作者： Yue-qi Mo Jian Huang Jia-xin Jiang Xian-yu Deng Yu-hua Niu Yong Cao institute of optoelectronic Materials & Devices Colleg of Material Science and engineering South china University of technology,Guangzhou 510640,china S china Univ Technol Coll Mat Sci & Engn Inst Optoelect Mat & Devices Guangzhou 510640 Peoples R China

It was found that traces of water in the reaction medium would result in a great increase of gel and a decrease of Molecular weight of the poly(2-methoxy,5-(2'-ethylhexyloxy)-1,4-phenylene vinylene) during the polymerization, which ultimately led to inferior film qualities and device properties. The device (ITO/PEDOT/MEH-PPV/Ba/Al) with MEH-PPV prepared under dry conditions has an external quantum efficiency of above 2.0%.

关键词： poly(phenylene vinylene) light-emitting diodes

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Implementation of the Fredkin gate with a three-qubit mixed-spin Heisenberg model

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Science china(Physics,Mechanics & Astronomy) 2010年第7期53卷 1276-1280页

作者： FAN QiuBo college of Mathematics and Physics,Xuzhou institute of technology,Xuzhou 221008,china 1. college of Mathematics and Physics Xuzhou Institute of Technology Xuzhou 221008 China

We show that a local unitary(LU) equivalent Fredkin gate can be obtained from the free evolution of three mixed-spin qubits by virtue of numerical simulation with only one *** spin-1 qubit acts as the control qubit,and two spin-1/2 qubits,which interact with the spin-1 qubit via the first neighbor spin interaction,respectively,play the role of target *** also examine the imperfect Fredkin gate operation by considering the effects of nonidentical coupling constants,uniform and inhomogeneous magnetic fields.

关键词： Fredkin gate mixed spin quantum computation

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Detection of bursts in neuronal spike trains by the mean inter-spike interval method

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Progress in Natural Science:Materials International 2009年第2期19卷 229-235页

作者： Lin Chena,b,Yong Deng c,Weihua Luo a,Zhen Wang a,Shaoqun Zenga,a Hubei Bioinformatics and Molecular Imaging Key Laboratory,Huazhong University of Science and technology,Wuhan 430074,china b college of Mechanical engineering,Guangxi University,Nanning,530004,china c college of optoelectronic Science of engineering,Huazhong University of Science and technology,Wuhan 430074,china [a]Hubei Bioinformatics and Molecular Imaging Key Laboratory Huazhong University of Science and Technology Wuhan 430074 China [b]College of Mechanical Engineering Guangxi University Nanning 530004 China [c]College of Optoelectronic Science of Engineering Huazhong University of Science and Technology Wuhan 430074 China

Bursts are electrical spikes firing with a high frequency,which are the most important property in synaptic plasticity and information processing in the central nervous system. However,bursts are difficult to identify because bursting activities or patterns vary with phys-iological conditions or external stimuli. In this paper,a simple method automatically to detect bursts in spike trains is described. This method auto-adaptively sets a parameter (mean inter-spike interval) according to intrinsic properties of the detected burst spike trains,without any arbitrary choices or any operator judgment. When the mean value of several successive inter-spike intervals is not larger than the parameter,a burst is identified. By this method,bursts can be automatically extracted from different bursting patterns of cultured neurons on multi-electrode arrays,as accurately as by visual inspection. Furthermore,significant changes of burst variables caused by electrical stimulus have been found in spontaneous activity of neuronal network. These suggest that the mean inter-spike interval method is robust for detecting changes in burst patterns and characteristics induced by environmental alterations.

关键词： Inter-spike interval Bursts Spike trains Multi-electrode arrays

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Investigation of Phase Excitation Effect on Mixing Control in Coaxial Jets

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Journal of Thermal Science 2009年第4期18卷 364-369页

作者： Yanming LIU,Baoguo WANG and Shuyan LIUSchool of Aerospace engineering,Beijing institute of technology,Beijing,100081,china School of Aerospace engineering Beijing Institute of Technology Beijing 100081 China

Detailed unsteady numerical simulation has been carried out to investigate the mechanism of adjacent syntheticjets and the influence of different phases on the mixing of coaxial jets. The results show the combined jet, formedby coupling the vortex pairs at the orifice of two adjacent actuators, can exhibit better controlling effect. Spanwisepressure difference appears because of the existence of phase difference between the left jet and right jet, whichresults in the variation of the combined jet. When the phase difference is greater than zero, mixing enhancementof coaxial jets can be achieved, but there are maximum phase difference and optimal phase difference. On thecontrary, application of adjacent synthetic jets always leads to the mixing reduction when phase difference is lessthan zero.

关键词： adjacent synthetic jets phase difference mixing controlling ability

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Raman Scattering and t-Phase Lattice Vibration of 3% (mole fraction) Y_2O_3-ZrO_2

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Journal of Materials Science & technology 2004年第5期20卷 485-489页

作者： Xinglun TANG and Xinhua ZHENGSchool of Materials Science and engineering, Beijing institute of technology, Beijing 100081, china Sch. of Mat. Sci. and Eng. Beijing Inst. of Technol. Beijing 100081 China

The Raman spectra of 3% (mole fraction) Y2O3-ZrO2 (3Y) are obtained at different temperature from 77 K to 853 K. The results show that 260 cm-1 Eg and 460 cm-1 Eg modes on the spectra shift toward lower wave number with the increase of temperature; meanwhile, the continuity of the Half Width at Half Maximum (HWHM) and wave number (frequency) of Raman bands are broken and t-phase only partially transforms to m-phase at 523 K. Based on the experimental results, this paper discusses the t-phase lattice vibration of 3Y and presents the images of vibration displacement of six Raman-active modes for t-phase of ZrO2. The analysis indicates that there are diversities existing in the displacement of the atomic vibration of Raman-active modes because of their different symmetries at various temperature, which leads to the different change tendencies of Raman bands. Furthermore, the abrupt changes of some Raman-active modes indicating the atomic displacement are assumed to be the condensations of phonon modes in the t→m phase transition.

关键词： Raman scattering Zirconia Phase transition Condensation of phonon

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