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Teaching and learning Chinese through Immersion:A Case Study from the North American Context

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Frontiers of Education in China 2020年第1期15卷 99-141页

作者： Chan lÜ Department of Asian languages&literature University of WashingtonSeattleWA 98195-3521USA

With the promise of achieving bilingualism,biliteracy,and cul.ural pluralism,Chinese immersion programs for students from kindergarten to 12th grade(K-12)in North America,especially the uS,have been proliferating in the past two *** on this rapidly growing population of non-native Chinese learners is also *** research synthesis focuses on 35 selected studies published in recent years on Chinese immersion in both Chinese and English language journals and *** review found that researchers are exploring a wide range of issues with respect to language and literacy development in Chinese immersion programs,including academic achievement in English,language and literacy acquisition in Chinese,instructional strategies and classroom interaction,as well as learners’language use and its sociolinguistic *** studies reflect a growing interest in and demand for learning more about the lesser-researched Chinese foreign language(CFl)learner population,and this review concludes with suggestions for future research on Chinese immersion based on its curricular features as well as specific considerations for conducting research with young,emergent bilingual and biliterate learners.

关键词： K-12 education Chinese immersion programs Chinese as a foreign language(CFl) academic achievement bilingual and biliteracy acquisition instructional strategies classroom interaction learner language

Microstructure of a Ni Matrix Composite Coating Reinforced by In-situ TiC Particles using Plasma Cladding

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材料热处理学报 2004年第05B期25卷 1041-1044页

作者： WuYu-ping WANGZe-hua lINPing-hua DepartmentofMaterialSciencesandEngineering HohaiUniversityNanjingChina DepartmentofMaterialSciencesandEngineering HohaiUniversityNanjingChina／／DepartmentofMaterialSciencesandEngineeringSoutheastUniversityNanjingChina

Plasma cladding process was used to prepare the TiC/Ni composite coating on the mild steel substrates. The TiC particles were synthesized in-situ. Microstructure and properties of the coating were investigated by optical microscopy, X-Ray diffraction, SEM, TEM and microhardness tester. The results show that the interface between the coating and the substrate is metal.urgically bonded. The coating was uniform and almost defect-free when [Ti+C] varied from 10% to 20% after ball milling. The microstructure of the coating is mainly composed of -Ni dendrite, interdendritic eutectic ( -Ni austenite, M23C6 and CrB) and TiC particles. Most of the TiC particles are spherical and a small fraction is blocky in size of l^2(im. The TiC particles are smaller at the bottom than near the top of the coating. The coating has a gradient microstructure and a highest hardness of lOOOHyO. 1.

关键词：显微结构等离子包覆复合涂层 TiC颗粒

Effect of Cyclic Annealing on Microstructure and Mechanical Properties of Medium Carbon Steel

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Journal of Iron and Steel Research International 2016年第2期23卷 145-150页

作者： Zhi-qing lÜ Hui-fang ZHANG Qing MENG Zhen-hua WANG Wan-tang Fu College of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina State Key laboratory of Metastable Material Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina

The microstructure and mechanical properties of medium carbon steel after cyclic heat treatment were in- vestigated. The effects of cyclic numbers and long time annealing on the microstructure and mechanical properties of the experimental steel were compared. A short duration （5 min） holding at 1023 K （above A1 temperature） and a short-duration （3 min） holding at 893 K are adopted in each cyclic heat treatment. The spheroidization is accelerated during cyclic heat treatment, and the spheroidizing ratio grows with cyclic numbers. After 12-cycle heat treatments, there are few incompletely spheroidized regions in the specimens, and cementite lamellae mostly change into cement- ite particles. The morphological character of cementite for 12 cycles is similar to that undergoing annealing for 10 h at 973 K. The strength of the experimental steel after 5-cycle heat treatment is the lowest in the following cyclic heat treatment, but it is still higher than that of specimens with subcritical annealing over a long period （10 h）. After 12- cycle heat treatment, the strength of the experimental steel is close to that of the normalized steel, and the plasticity is the best in all heat treated specimens.

关键词： rapid spheroidizing mechanical property cyclic annealing cementite medium carbon steel

Identification of Hammerstein systems with asymmetric dead-zone nonlinearities using canonical parameterized model

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控制理论与应用（英文版） 2012年第4期10卷 511-516页

作者： Xiaohua lü Xuemei REN School of Automation Beijing Institute of Technology

A non-iterative identification method with parameterization of the unknown dead-zone is proposed for Hammerstein systems in presence of asymmetric dead-zone nonlinearities. The canonical parameterized model which is a single expression without segmentation is utilized to describe the dead-zone, based on which a universal-type parametric model can be established to approximate the entire system. This model can be established without separating the nonlinear part from the linear part. The dead-zone parameters and the coefficients in the linear transfer function can be estimated simultaneously according to the proposed algorithm. Numerical experiments are presented to il.ustrate the effectiveness of the proposed scheme.

关键词： Hammerstein systems Asymmetric dead-zone nonlinearity Canonical parameterized model System identification

The comparison of ensemble or deterministic dispersion modeling on global dispersion during Fukushima Dai-ichi nuclear accident

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Science China Earth Sciences 2015年第3期58卷 356-370页

作者： SHENG li SONG ZhenXin Hu JiangKai lü Kai TONG hua lI Bing QIAO QingDang National Meteorological Center China Meteorological Administration Nuclear and Radiation Safety Center Ministry of Environmental Protection of the People's Republic of China

Ensemble forcasting,originally developed for weather prediction,is lately being extended to atmospheric dispersion applications,which is a new,effective methodology for improving the atmospheric dispersion numerical *** March 2011,due to the massive 9.0 earthquakes and ensuing tsunami that struck off the northern coast of the island of Honshu,the Fukushima Nuclear Plant I had the substantial leak of radioactive materials into surrounding environment and *** aim at the global dispersion modeling of atmospheric radionuclides from Fukushima Nuclear Accident,this paper presents two approaches of atmospheric dispersion forecasting:ensemble dispersion modeling(EDM) and deterministic dispersion modeling(DDM),conducts the globally dispersion modeling cases for Fukushima nuclear accident,and analyzes and evaluates the simulation results using observation *** this paper,EDM includes three different perturbation methods:meteorological perturbation method,turbulence perturbation method,and physical parameterization ensemble forecasting *** simulation results show that the trajectories from EDM have a better performance,which is in better agreement with the atmospheric circulation and observation data; the spread from DDM is slower and not as far as ***,the results from EDM display a better performance in the modeling of transport from Japan to China East Sea on April *** reasons for these results are:the techniques of MET and TuR are performed by adding perturbations on mean wind and turbulent velocity,respectively; the various different flow fields will result in far spreading in horizontal and the simulation results closer to observation; PHY is performed by using different diffusion physical parameterizations and produces the perturbations on vertical wind,which results the spreading in smaller range and discontinuous in ***,the comparative analysis between modeling results and observation data shows that all cases r

关键词： ensemble dispersion modeling deterministic dispersion modeling atmospheric dispersion Fukushima nuclear accident

leaching behavior of phosphorous compounds from sewage sludge ash based on quantitative X-ray diffraction analysis

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Waste Disposal and Sustainable Energy 2020年第2期2卷 113-125页

作者： Pinjing He Xiaotong Zhang Fan lü liming Shao hua Zhang Institute of Waste Treatment and Reclamation College of Environmental Science and EngineeringTongji UniversityShanghai 200092China State Key laboratory of Pol.ution Control and Resource Reuse Tongji UniversityShanghai 200092China Shanghai Institute of Pol.ution Control and Ecological Security Shanghai 200092China

Phosphorus(P)is an essential and limited *** sewage sludge ash(ISSA)contains a high amount of P,which can be recovered using chemical leaching ***,the recovery ratio depends on the speciation of P and the leaching *** this study,hydrochloric acid was used as a leaching agent,and the effects of the hydrochloric acid concentration,leaching time,temperature,and liquid-solid ratio on the P leaching ratio were ***,the co-leaching of macro-metals Ca,Al,Fe,and Mg was *** results showed that P leached rapidly within 30 min,where the leaching rate reached more than 80%and then gradually *** leaching concentrations of Ca and Mg had a significant correlation(correlation coefficient r^(2)>0.90),and both were leached *** and P had similar leaching patterns,where the leaching rates increased initially and then decreased with time at 0.2 mol/l *** to X-ray diffraction analysis and Rietveld refinement,the P in ISSA was mainly present in the forms of Mg_(3)Ca_(3)(PO_(4))_(4) and AlPO_(4).When leached using 0.2 mol/l HCl at 55℃ with a liquid-to-solid ratio of 20 l/kg,the AlPO_(4) and Fe_(3)(H_(2)O)_(3)(PO_(4))_(2) in ISSA dissolved initially and then precipitated on the surface of the solid phase,thereby impeding further P leaching.

关键词： Sewage sludge ash Acid leaching Phosphorous speciation Quantitative X-ray diffraction analysis Rietveld refinement

Co-Treatment of EFF and 1-MCP for Enhancing the Shelf-life and Aroma Volatile Compounds of Oriental Sweet Melons(Cucumis melo *** Makino)

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Journal of Integrative Agricul.ure 2014年第1期13卷 217-227页

作者： BAI Xiao-hang TENG lu-hua lü De-qing QI Hong-yan Key laboratory of Protected Horticul.ure Education Ministry and Liaoning ProvinceDepartment of HorticultureShenyang Agricultural University

Compared to other melon types, oriental sweet melon （Cucumis melo var. makuwa Makino） is quite a different species with a shorter shelf-life due to its typical climacteric behavior and thin pericarp. The purpose of this experiment is to explore the effects of co- treatment of enhanced freshness formulation （EFF） and 1-methylcyclopropene （1-MCP） on physiological changes and the content of aroma volatile compounds introduced by them of two oriental sweet melon cultivars （Yumeiren and Tianbao） during storage. The melons were stored in incubators with temperature of 15~C and a relative humidity of 85% for 24 d during which fruit quality and related physiological index were measured. Compared to the control, both treatments delayed fruit weight loss rate and kept the fruit firmness, water content and soluble solids content. Ascorbate peroxidase （APX） and phenylalanine ammonia lyase （PAl） activities showed fluctuations in treated melons, while lipoxygenase （lOX） activity （P〈0.01） and malondialdehyde （MDA） content （P〈0.05） decreased compared to control. During the early stage of storage, alcohols and aldehydes were the main volatile compounds, and esters gradually increased during storage. Of all the esters, acetic esters were the main components, followed by oxalic acid esters and other esters. The total content of aroma volatile compounds, esters, alcohols and aldehydes of co-treated melons were all higher than those of 1-MCP treated and control melons. In addition, the aroma volatile peak of co-treated melons occurred later than that of 1-MCP treated and control melons. In summary, co-treatment of EFF and 1-MCP was more beneficial than 1-MCP treatment to delay ripening and senescence, maintain fruit quality, enhance shelf-life and improve levels of aroma volatile compounds.

关键词： oriental sweet melon enhanced freshness formulation l-methylcyclopropene aroma volatile compounds shelf-life

Flow Injection Chemiluminescence Analysis of low level Concentration of Hydrazine

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Chinese Chemical letters 2001年第9期12卷 799-802页

作者： Zheng hua SONG lin WANG Ji Hong lü Tie Zhu ZHAO Department of Chemistry Northwest UniversityXi’an 710069 Xi’an Modern Chemistry Research Institute Xi’an 710060

Combined with flow-injection (FI) technology, a simple chemiluminescence (Cl) method was developed for hydrazine determination in this paper. It was found that hydrazine could greatly decrease the strong Cl signal produced by the reaction between luminol and hexacyanoferrate (III) in alkaline medium. The decreased Cl intensity was linear with hydrazine concentration in the range of 5.0×10-9 g·ml-1 to 4.0×10-5 g·ml-1, and the limit of detection was 2.0×10-9 g·ml-1 (3σ) with a relative standard deviation of 2.4~4.1% (n=5).

关键词： Hydrazine flow injection chemiluminescence

Investigation of natural VOC emitted from tropical vegetations in China

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Journal of Environmental Sciences 2005年第1期17卷 8-13页

作者： WANGZhi-hui BAIYu-hua l.uZhao-rong WANGXue-song lIQing-junt l.F.Klinger CollegeofEnvironmentalSciences PekingUniversityBeijing100871China XishuangbannaTropicalBotanicalGarden ChineseAcademyofSciencesKunming650223China InstituteofNoeticSciences 101SanAntonioRoadPetalumaCA94952USA

Twenty three kinds of typical plants in Xishuangbanna, the tropical area of southwestern China, were screened to estimate the emission rates of isoprene and monoterpenes by adopting bag enclosure and curette sampling methods followed by a GC FID analysis. It was found that the Ficus species were mainly emitting isoprene and most tropical vegetations were mainly releasing monoterpenes. The results also showed that the emissions of isoprene were affected by both temperature and PAR(Photosynthetic Active Radiation), while monoterpene emissions were mainly temperature dependent.

关键词： VOC isoprene monoterpenes emission factor Xishuangbanna