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Multi-face detection based on downsampling and modified subtractive clustering for color images

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 72-78页

作者： KONG Wan-zeng zhu shan-an School of Electrical Engineering Zhejiang University Hangzhou 310027 China

This paper presents a multi-face detection method for color images. The method is based on the assumption that faces are well separated from the background by skin color detection. These faces can be located by the proposed method which modifies the subtractive clustering. The modified clustering algorithm proposes a new definition of distance for multi-face detection, and its key parameters can be predetermined adaptively by statistical information of face objects in the image. Downsampling is employed to reduce the computation of clustering and speed up the process of the proposed method. The effectiveness of the proposed method is illustrated by three experiments.

关键词： Multi-face detection Skin color Modified subtractive clustering Downsampling

Effects on the mixing process of a coiled tube after a T-junction:Simulation and correlation

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2441-2447页

作者： shan zhu Kai Wang Yangcheng Lü State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University

Simulations were performed to examine the effects of a coiled tube after a T-junction on the mixing and flow characteristics. A coiled tube was found to have two effects: inducing a radial flow and flattening the axial velocity distribution, which enhances and weakens the mixing, respectively. In the straight tube section connecting the Tjunction and coiled tube, the latter may dominate and cause the mixing to deteriorate. An experiment was performed with the Villermaux/Dushman method to verify the simulation results. Based on a mixing performance simulation with various fluid and geometric structure parameters, a dimensionless correlation was obtained that can be used to determine the mixing intensity along the coiled tube with a deviation of less than 1.5%.These results provide guidance for designing a coiled tube or optimizing the operating conditions to meet the mixing requirements of specific chemical processes.

关键词： Mixing T-junction Simulation Coiled tube Correlation Flow

Hierarchically 1D CdS decorated on 2D perovskite-type La_(2)Ti_(2)O_(7) nanosheet hybrids with enhanced photocatalytic performance

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Rare Metals 2021年第5期40卷 1067-1076页

作者： Liang Mao Xiao-Yan Cai Ming-shan zhu School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China Jiangsu Province Engineering Laboratory of High Efficient Energy Storage Technology and Equipment China University of Mining and TechnologyXuzhou 221116China School of Environment Jinan UniversityGuangzhou 511443China

In this paper,a heterojunction of hierarchically one-dimensional(1D)cadmium sulfide(CdS)nanowires decorated on the two-dimensional(2D) La_(2)Ti_(2)O_(7) (LTO)has been fabricated by a simple two-step hydrothermal *** structure,morphology and surface chemical composition of CdS/LTO were studied by a variety of characterizations,in which the X-ray photoelectron spectroscopy(XPS)results showed a strong interaction between CdS and LTO through S-O *** typeⅡband alignment of CdS/LTO for favorable electron transfer from CdS to LTO and hole transfer from LTO to CdS was clarified by ultraviolet-visible(UV-Vis)diffuse reflectance spectroscopy and Mott-Schottky(M-S)plot *** the absence of any co-catalyst,H2 production from water splitting and Rhodamine B(RhB)decomposition in aqueous solution were carried out to evaluate the photocatalytic activities,showing that the photocatalytic performance of CdS/LTO was superior to that of pure LTO and CdS under visible light and simulated *** optimal CdS content in the CdS/LTO system was determined to be 7.5 wt%.The present results show an effective pathway to design a 1D/2D heterojunction photocatalyst in the face of overwhelming problems of energy crisis and environmental pollution.

关键词： Cadmium sulfide Lanthanum titanium oxide Heterojunction H_(2)production Dyes degradation

Extended hopanes and 8,14-secohopanes up to C_(40)in unbiodegraded marine oils from the Tarim Basin,NW China

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Petroleum Science 2022年第2期19卷 498-508页

作者： Jian-Ping Bao Cui-shan zhu Xi Yang Hubei Key Laboratory of Petroleum Geochemistry and Environment Key Lab.of Exploration Technologies for Oil&Gas ResourcesMinistry of EducationGeochemistry DepartmentYangtze UniversityWuhan430100HubeiChina

Extended 17α(H),21β(H)-hopanes and three series of 8,14-secohopanes up to C_(40),including 8α(H),14α(H),17α(H),21β(H)-,8α(H),14α(H),17β(H),21α(H)-and 8α(H),14β(H),17β(H),21α(H)-,were detected by GC-MS-MS method in the branched/cyclic hydrocarbon fractions of some unbiodegraded marine oils from the Tazhong uplift in the Tarim Basin,NW *** coexistence of extended hopanes and 8,14-secohopanes up to C_(40)in unbiodegraded oils suggests that they are primary and independent on *** similarity of distribution and composition for extended hopanes and 8,14-secohopanes up to C_(40)in unbiodegraded oils proposes that they could be derived from a similar biological ***,an abrupt decrease up to 3-5 times in the relative abundance from C_(35)to C_(36)in C_(31-40)extended hopanes and extended 8,14-secohopanes suggests that C_(31-35)and C_(36-40)extended hopanes and extended 8,14-secohopanes should have their own biological *** known C35bacteriohopanetetrol should be biological precursor of C_(31-35)extended hopanes and 8,14-secohopanes,but an unknown C_(40)functionalized hopanoid could be biological precursor of C_(36-40)extended hopanes and 8,*** attention should be paid to their potential roles in oil-source correlation for severely biodegraded oils based on their widespread occurrence in various source rocks,unbiodegraded and severely biodegraded oils.

关键词： Extended hopanes Extended 8,14-secohopanes Biomarkers Bacteriohopanetetrol Unbiodegraded marine oils Tazhong Uplift Tarim Basin

Simulation of the mixing process in a straight tube with sudden changed cross-section

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Chinese Journal of Chemical Engineering 2016年第6期24卷 711-718页

作者： Yangcheng LU shan zhu Kai Wang Guangsheng Luo State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University Beijing 100084 China

In this work, we revised the expression of mixing intensity to describe the mixing output through a cross section in a flow system by considering heterogeneity of flow field, and carefully investigated the mixing process along a straight tube with expanding/contracting cross section by simulation method. The simulation results show that a sudden expansion of cross section has remarkable mixing intensification effect within a limited period(on the sub-second scale) or tube-length(on the millimeter scale), corresponding to the generation of considerable local vortices determined by both the flow capacity and the ratio of cross section change; a sudden contraction of cross section has instantaneous but weak mixing intensification effect; through introducing a local expansion structure with proper length, as the combination of sudden expansion and sudden contraction, their mixing intensification effects could be superposed. Besides, the rationality and importance are experimentally verified to explore the time profile of mixing intensity and carry out the vortex analysis by simulation for enhancing the selectivity of a complicated reaction system. These progresses may lead to more meaningful quantitative description of mixing process in a flow microreactor for some specific chemical processes.

关键词： MixingIntensificationSimulationSudden change in cross-sectionVortex

Properties of TRPO-HNO_3 complex used for direct dissolution of lanthanide and actinide oxides in supercritical fluid CO_2

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Science China Chemistry 2007年第6期50卷 759-763页

作者： DUAN WuHua zhu LiYang JING shan zhu YongJun Institute of Nuclear and New Energy Technology Tsinghua University Beijing 102201 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 102201 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 102201 China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 102201 China

The mixed trialkylphosphine oxide-nitric acid (TRPO-HNO3) complex prepared by contacting pure TRPO with concentrated HNO3 may be used as additives for direct dissolution of lanthanide and actinide ox- ides in the supercritical fluid carbon dioxide (SCF-CO2). Properties of the TRPO-HNO3 complex have been studied. Experimental results show when the initial HNO3/TRPO volume ratio is varied from 1:7 to 5:1, the concentration of HNO3 in the TRPO-HNO3 complex changes from 2.12 to 6.16 mol/L, the [HNO3]/[TRPO] ratio of the TRPO-HNO3 complex changes from 0.93 to 3.38, and the content of H2O in the TRPO-HNO3 complex changes from 0.97% to 2.70%. All of the density, viscosity and surface tension of the TRPO-HNO3 complex change with the concentration of HNO3 in the complex. The protons of HNO3 and H2O in the complex undergo rapid exchange to exhibit a singlet resonance peak in NMR spectra with D2O insert. When the TRPO-HNO3 complex dissolves in a low dielectric constant solvent, small droplets of HNO3 appear which can be detected by NMR.

关键词： TRPO-HNO3 complex, property, supercritical fluid carbon dioxide, dissolution

Effects of the continuous cooling process conditions on the crystallization and liberation characteristics of anosovite in Ti-bearing titanomagnetite smelting slag

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International Journal of Minerals,Metallurgy and Materials 2019年第9期26卷 1120-1128页

作者： Zhen Wang Hao-yan Sun Qing-shan zhu State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

This study involved the investigation of the effects of the continuous cooling process conditions on the crystallization and liberation characteristics of anosovite in Ti-bearing titanomagnetite smelting slag. The samples were heated until melting and then the temperature was held at 1650℃ for nearly 0.5 h;subsequently, the samples were cooled at different cooling rates to different temperatures and water-quenched after being held for different times at these temperatures. Last, the obtained crystallized samples were used to analyze the crystallization and liberation characteristics. It was found that, during the continuous cooling process, anosovite particles were found to initially precipitate in the slag at a relatively high crystallization temperature, showing the characteristics of euhedral crystal. The precipitation and growth of anosovite grain is strong and the morphology of anosovite was basically not affected by the continuous cooling conditions. From the morphology perspective, the formed anosovite is an excellent Ti-rich phase to be selective separated. The formation of spinel and diopside is negative for the liberation and selective separation of the anosovite phase. The crystallization diagrams of TiO2-MgO-CaO-SiO2-Al2O3-FeO slag undergoing different continuous cooling processes were constructed to help to determine the optimal continuous cooling–quenching condition for selective separation of anosovite. Moreover, the addition of B2O3 can enlarge the range of the optimal continuous cooling–quenching conditions for selective separation of anosovite.

关键词： titanium-bearing slag crystallization anosovite liberation titanomagnetite

Adsorption behavior of Pd(Ⅱ) from aqueous solutions by D201 resin

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Rare Metals 2011年第5期30卷 470-476页

作者： XIONG Chunhua zhu shan YAO Caiping CHEN Qing Department of Applied Chemistry Zhejiang Gongshang University Hangzhou 310012 China

The adsorption and desorption behaviors of Pd（Ⅱ） on D201 resin were investigated. The effects of parameters including HCl concentrations, initial metal ion concentrations, contact time, and temperature on the adsorption of Pd（Ⅱ） were studied by batch method. The HCl concentration for studying the effects was set from 0.01 to 2 mol·L-1 and the optimal adsorption condition is in 0.01 mol·L-1 HCl solution. The adsorption isotherm of Pd（Ⅱ） on D201 resin was determined and the equilibrium data fitted the Langmuir model better than the Freundlich model. The maximum uptake capacity of Pd（Ⅱ） was 253 mg·g-1 at 298 K. The adsorption could be best described by the liquid film diffusion model. The enthalpy variation （ΔH） and entropy change （ΔS） of adsorption were equal to 2.49 kJ·mol-1 and 74.8 J·（mol·K）-1 respectively, indicating that the adsorption was endothermic in nature. Furthermore, the negative value of ΔG showed that movement of adsorbate from the solution to adsorbent surface was a spontaneous process. Pd（Ⅱ） could be eluted with 0.5 mol·L-1 HNO 3 solution. Thomas model was applied to experimental column data to determine the characteristic parameters of the column useful for process design.

关键词： adsorption palladium resins thermodynamics kinetics

Transcriptional divergence between cDC1s and cDC2s: an AP1–IRF composite element-dependent program

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Cellular & Molecular Immunology 2021年第7期18卷 1618-1619页

作者： shan zhu Chao Niu Jingtao Chen Key Laboratory of Organ Regeneration&Transplantation of the Ministry of Education The First Hospital of Jilin UniversityChangchun130061PR China Department of Cancer Center The First Hospital of Jilin UniversityChangchun130021PR China

Conventional dendritic cells(cDCs)are categorized into two main subsets,cDC1 and cDC2,distinguished by their differential expression of cell surface markers,and the development of these two cDC subsets is dependent on interferon regulatory factor 8(IRF8)and IRF4,respectively.1 Kim et al.2 recently reported that cDC1 can be distinguished from cDC2 based on an AP1–IRF composite element(AICE)-dependent gene ***8 at a high concentration engages AICEs at enhancer regions to direct a program toward establishing the cDC1 *** findings provide a molecular basis to explain the distinct transcriptional signatures of cDC1s and cDC2s.

关键词： al. interferon element