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Land Use and Land Cover Change on Slope in Qiandongnan Prefecture of Southwest China

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Journal of Mountain Science 2014年第3期11卷 762-773页

作者： LU Liang guo luo ZHAO Song-ting College of Life and Environmental Science Minzu University of China Geomatics Centre of Zhejiang Beijing Institute of Landscape Architecture

This study uses DEM （Digital Elevation Model） data and remote sensing maps of the study area in 1993, 1999, and 2009 to analyze the slope gradient change of land use patterns in Qiandongnan Prefecture, Guizhou province, China. The land use data were classified into five types, forest, farmland, grassland, water and built-up, the slope gradients were divided into four grades. Indices for analyzing land use features were defined by their proportions, transformation matrixes, land use degree and changes The results showed that all land use types can be found at every gradient. Generally, with the slope degree increased, the area of forest being augmented as well, while the area of the other land use types （farmland, grassland and build-up） declined. Moreover, a mass of farmland were shifted from other land use types from o° to 25°, while a quantity of forest were transformed from the other land use types on 〉 25° from 2993 to 2009. In terms of land use degree and changes, the area of farmland and buildup land use types decreased when slope degree increased. Finally, we calculated the five landscape pattern metrics： Patch Density （PD） value, Largest Patch Index （LPI）, Shannon＇s Diversity Index （SHDI）, Area-Weighted Mean Shape Index （AWMSI） and Contagion Index （CONTAG）. The results of metricsanalysis showed that PD values, SHDI values and CONTA values had a similar variation trend, that is, they decreased when slope degree increased. There was no obvious variation trend on LPI value.

关键词： Land use Land cover change Spatialgradient slope Landscape metrics Qiandongnanprefecture

Blue Generation in a Periodically Poled LiTaO3 by Frequency Tripling and 1342 nm ND:YVO4 Laser

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Chinese Physics Letters 2002年第7期19卷 944-946页

作者： He Jing-Liang, Liu Jie, luo guo-Zhen Laboratory of Modern Optics Shandong Normal University Ji\'nan 250014 National Laboratory of Solid State Microstructure Nanjing University Nanjing 210093

We report on an efficient blue light generation in periodically poled LiTaO3 by the frequency tripling of a quasi-continuous 1342 nm Nd:YVO4 laser. The period of the sample was 14.778 μm. Blue light with an average power of 138 mW was generated from a 18 mm long crystal in a single-pass process under an average fundamental power of 713 mW. The internal conversion efficiency was 19.3%.

关键词： Tantalum compounds

Numerical simulation on characteristics of COREX shaft furnace with central gas distribution

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Journal of Iron and Steel Research International 2019年第6期26卷 567-577页

作者： Xing-sheng Zhang Zong-shu Zou Zhi-guo luo Department of Ferrous Metallurgy School of Metallurgy Northeastern University Shenyang 110819 Liaoning China Key Laboratory of Ecological Utilization of Multi-metallic Mineral of Education Ministry Northeastern University Shenyang 110819 Liaoning China

A three-dimensional steady-state mathematical model, considering the chemical reactions and transfers of momentum, heat and mass between the gas and solid phases, was developed to investigate the characteristics of the shaft furnace with the central gas distribution (CGD) device. The model was verified by the practical production data of a COREX-3000 shaft furnace, and then, it was used to study the inner characteristics of the shaft furnace with CGD. The results show that, compared with the COREX shaft furnace without CGD, the gas utilization rate (UR) and solid metallization rate (MR) increase from 33.66% to 34.18% and 60.4% to 61.8%, respectively. Especially, the standard deviation of solid MR decreases from 6.9% to 0.8%, which means that the MR of direct reduced iron from the furnace with CGD is more uniform than that without CGD. Additionally, the effects of operational conditions and CGD design on gas UR, solid MR and direct reduced iron uniformity were further discussed and the optimized conditions were suggested.

关键词： COREX shaft furnace Central gas distribution Gas utilization Solid metallization Direct reduced iron uniformity

Study on the quality of recombinant proteins using matrix-assisted laser desorption ionization time of flight mass spectrometry

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World Journal of Gastroenterology 1999年第3期5卷 235-240页

作者： ZHOU guo-Hua luo guo-An SUN guo-Qing CAO Ya-Cheng and ZHU Ming-Sheng 清华大学北京 100084 中科院南京土壤所江苏南京华东医学生物技术所江苏南京

AIM To study the possibility of matrix-assistedlaser desorption/ionization time of flight massspectrometry (MALDI--TOF MS) for controllingthe quality of recombinant *** By using MALDI--TOF MS, themoleCular weights and purity of recombinantbioactive proteins were *** The molecular weights and puritywere obtained in nine recombinant bioactiveproteins, including interleukin 2, tumor necrosisfactor Q, granulocyte--macrophage colonystimulating factor, interferon aZb, interferon al,erythropoietin, calmodulin and its fragment, andneuronal nitric oxide synthase were ***--TOF MS was also used to assay specificproteins in the mixtures and to characterize theerythropoietin tryptic *** The results showed that MALDITOF MS can be employed for the effective qualitycontrol of recombinant proteins.

关键词： MALDI time

Mechanism and simulation of droplet coalescence in molten steel

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International Journal of Minerals,Metallurgy and Materials 2017年第11期24卷 1251-1259页

作者： Bing Ni Tao Zhang Hai-qi Ni Zhi-guo luo Department of Metallurgical Technology Central Iron and Steel Research Institute School of Metallurgy Northeastern University

Droplet coalescence in liquid steel was carefully investigated through observations of the distribution pattern of inclusions in solidified steel samples. The process of droplet coalescence was slow, and the critical Weber number(We) was used to evaluate the coalescence or separation of droplets. The relationship between the collision parameter and the critical We indicated whether slow coalescence or bouncing of droplets occurred. The critical We was 5.5, which means that the droplets gradually coalesce when We ≤ 5.5, whereas they bounce when We > 5.5. For the carbonate wire feeding into liquid steel, a mathematical model implementing a combined computational fluid dynamics(CFD)–discrete element method(DEM) approach was developed to simulate the movement and coalescence of variably sized droplets in a bottom-argon-blowing ladle. In the CFD model, the flow field was solved on the premise that the fluid was a continuous medium. Meanwhile, the droplets were dispersed in the DEM model, and the coalescence criterion of the particles was added to simulate the collision-coalescence process of the particles. The numerical simulation results and observations of inclusion coalescence in steel samples are consistent.

关键词： mechanism simulation droplet collision coalescence molten steel

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Journal of Integrative Plant Biology 2012年第10期54卷 814-827页

作者： guo luo Hongya Gu Jingjing Liu Li-Jia Qu State Key Laboratory for Protein and Plant Gene Research College of Life SciencesPeking-Tsinghua Center of Life SciencesPeking UniversityBeijing 100871China The National Plant Gene Research Center Beijing 100101China

Ubiquitination of proteins is one of the critical regulatory mechanisms in eukaryotes. In higher plants, protein ubiquitination plays an essential role in many biological processes, including hormone signaling, photomorphogenesis, and pathogen defense. However, the roles of protein ubiquitination in the repro- ductive process are not clear. In this study, we identified four plant-specific RING-finger genes designated Aberrant_Pollen Development 1_ （APD1） to APD4, as regulators of pollen mitosis II （PMII） in Arabidopsis thaliana （L.）. The apdl apd2 double mutant showed a significantly increased percentage of bicellular-like pollen at the mature pollen stage. Further downregulation of the APD3 and APD4 transcripts in apdl apd2 by RNA interference （RNAi） resulted in more severe abnormal bicellular-like pollen phenotypes than in apdl apd2, suggesting that cell division was defective in male gametogenesis. All of the four genes were expressed in multiple stages at different levels during male gametophyte development. Confocal analysis using green florescence fusion proteins （GFP） GFP-APD1 and GFP-APD2 showed that APDs are associated with intracellular membranes. Furthermore, APD2 had E2-dependent E3 ligase activity in vitro, and five APD2-interacting proteins were identified. Our results suggest that these four genes may be involved, redundantly, in regulating the PMII process during male gametogenesis.

关键词： Male gametogenesis pollen mitosis II RING-finger E3 ligase Arabidopsis.

Robust cubature Kalman filter method for the nonlinear alignment of SINS

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Defence Technology（防务技术） 2021年第2期17卷 593-598页

作者： Shi-luo guo Ying-jie Sun Li-min Chang Yang Li Department of Instrument Electric Aviation University Air ForceChangchunPeople’s Republic of China

Nonlinear initial alignment is a significant research topic for strapdown inertial navigation system(SINS).Cubature Kalman filter(CKF)is a popular tool for nonlinear initial *** CKF assumes that the statics of the observation noise are pre-given before the filtering ***,any unpredicted outliers in observation noise will decrease the stability of the *** view of this problem,improved CKF method with robustness is *** fading factors are introduced to rescale the observation noise *** the update stage of the filter can be autonomously tuned,and if there are outliers exist in the observations,the update should be less *** the Gaussian assumption of KF,the Mahalanobis distance of the innovation vector is supposed to be Chi-square *** a judging index based on Chi-square test is designed to detect the noise outliers,determining whether the fading tune are *** proposed method is applied in the nonlinear alignment of SINS,and vehicle experiment proves the effective of the proposed method.

关键词： SINS Nonlinear alignment Cubature Kalman filter Robust Multiple fading factors Hypothesis test

Reversible electrochemistry of DNA on multi-walled carbon nanotube modified electrode

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Chinese Chemical Letters 2007年第7期18卷 861-864页

作者： Hong Xia luo Zhi Xin guo Nan He Department of Chemistry Renmin University of China Beijing 100872 China

Calf thymus DNA was electrochemically oxidized at a multi-walled carbon nanotube modified electrode. The potentials for DNA oxidation at pH 7.0 were 0.71 and 0.81 V versus SCE, corresponding to the oxidation of guanine and adenine residues,respectively. The initial 6e-oxidation of adenine, observed in the first scan, resulted a quasi-reversible 2e-redox process of the oxidation product in the following scans.

关键词： Carbon nanotube DNA Cyclic voltammetry Reversible

Synthesis of nanosized tungsten carbide from phenol formaldehyde resin coated precursors

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Rare Metals 2008年第2期27卷 201-204页

作者： luo Ji guo Zhimeng GAO Yuxi LIN Tao School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Nanosized tungsten carbide was synthesized from phenol formaldehyde resin （PF） coated tungsten precursors. The process has three steps in which nanosized tungsten particles were first coated with PF, then the precursors were carburized at 950℃, and finally the carburized powders were treated in flowing wet hydrogen atmosphere at 940℃ to remove the uncombined carbon. The obtained powders were characterized using X-ray diffraction analysis （XRD）, field-emission scanning electron microscopy （FESEM）, small angle X-ray scattering （SAXS）, and combustion-gas-volume method. The results indicated that single-phase WC could be synthesized using excessive PF as carburizer at a much lower temperature compared with using mixed carbon black. After wet hydrogen treating, the mean size of the obtained WC particles was 94.5 nm and the total carbon content was 6.18 wt.%.

关键词： cemented carbide nanosized tungsten carbide carburization phenol formaldehyde resin