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Characterizing ionic species in PM_(2.5) and PM_(10) in four Pearl River Delta cities,South China

Journal of Environmental Sciences 2007年第8期19卷 939-947页

作者： lai Sen-chao ZOU Shi-chun CAO Jun-ji LEE Shun-cheng HO Kin-fai School of Chemistry and Chemical Engineering Sun Yat-sen University Guangzhou 510275 China. Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi＇ an 710075 China

PM2.5 and PM10 samples were collected at four major cities in the Pearl River Delta （PRD）, South China, during winter and summer in 2002. Six water-soluble ions, Na^＋, NH4＋, K^＋, Cl^-, NO3^- and SO4^2- were measured using ion chromatography. On average, ionic species accounted for 53.3% and 40.5% for PM2.5 and PM10, respectively in winter and 39.4% and 35.2%, respectively in summer. Secondary ions such as sulfate, nitrate and ammonium accounted for the major part of the total ionic species. Sulfate was the most abundant species followed by nitrate. Overall, a regional pollution tendency was shown that there were higher concentrations of sulfate, nitrate and ammonium in Guangzhou City than those in the other PRD cities. Significant seasonal variations were also observed with higher levels of species in winter but lower in summer. The Asian monsoon system was favorable for removal and diffusion of air pollutants in PRD in summer while highly loading of local industrial emissions tended to deteriorate the air quality as well. NO3^-/SO4^2- ratio indicated that mobile sources have considerably contribution to the urban aerosol, and stationary sources should not be neglected. Besides the primary emissions, complex atmospheric reactions under favorable weather conditions should be paid more attention for the control of primary emission in the PRD region.

关键词： water-soluble ions seasonal and spatial variations Pearl River Delta

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Syntheses and Crystal Structures of Cobalt(II) Chloride Complexes of 1,3-Bis(pyridyl-4-ylthio)propan-2-one

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Chinese Journal of Structural Chemistry 2006年第5期25卷 511-516页

作者： WU Ben-lai WU Ming-Yan GONG Ya-Qiong CHEN Bai-Quan HONG Mao-chun State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

Reactions of 1,3-bis（pyridyl-4-ylthio）propan-2-one L and COCl2·6H2O under different conditions gave two new cobalt（Ⅱ）-chloride-L complexes with distinct structures. Complex [Co（L）2Cl2]·0.5CH3OH}n 1 prepared by solvothermal treatment is a 3D network, whereas complex {[Co3（L）2Cl6（DMF）4]·2CH3OH·H2O} 2 obtained in DMF-diethyl ether system is a discrete acyclic trimer. Crystal data for 1： space group lbca, a = 15.993（4）, b = 18.454（5）, c = 21.506（6）A, V= 6347（3） ,A^3, Z = 8, Dc = 1.462 g/cm^3,μ = 1.005 mm^-1, F（000） = 2864, C26.5H26Cl2CoN4O2.5S4, Mr = 698.58, the final R = 0.0499 and wR = 0.1024. Crystal data for 2： space group P1^-, a = 9.9177（6）, b = 11.0871 （4）, c = 15.5490（12） ,A, α = 83.1834（14）,β = 88.910（13）, γ = 71.096（ 11 ）°, V = 1605.8（2） A^3, Z = 1, Dc = 1.362 g/cm^3,μ= 1.194 mm^-1, F（000） = 677, C40H62Cl6Co3N8O9S4, Mr = 1316.71, the final R = 0.0666 and wR =0.1575.

关键词： cobalt chloride complex 1,3-bis(pyridyl-4-ylthio)propan-2-one crystal structure

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Modeling of an Impinging Oxygen Jet on Molten Bath Surface in 150t EAF

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Journal of Iron and Steel Research International 2011年第9期18卷 13-20页

作者： HE chun-lai ZHU Rong DONG Kai QIU Yong-quan SUN Kai-ming Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China Tianjin Pipe (Group) Corporation Tianjin 300301 China

A transient three-dimensional mathematical model has been developed to analyze the three-phase flow in a 150 t EAF （electric arc furnace） using oxygen. VOF （multiphase volume of fluid） method is used to simulate the behaviors of molten steel and slag. Numerical simulation was conducted to clarify the transient phenomena of oxygen impingement on molten bath. When oxygen jet impinges on the surface of molten bath, the slag layer is broken and the penetrated cavity in molten steel is created. Simultaneously, the wave is formed at the surface of uncovered steel on which the slag layer is pushed away by jet. The result of numerical simulations shows that the area and velocity of uncovered steel created by impingement, jet penetration depth change from 0. 10 m2 , 0. 012 5 m/s, 3.58 cm to 0.72 m2 , 0. 1445 m/s, 11.21 cm, when the flow rate of an oxygen lance varies from 500 to 2000 m3/h. The results have been validated against water model experiments. More specially, the relation between the penetration depth and oxygen flow rate predicted by numerical simulation has been found to agree well with that concluded by water model.

关键词： electric arc furnace three-phase flow numerical simulation

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New synthetic approach for the preparation of 2-aryl-thiazolo[4,5-b]pyridines via Liebeskind–Srogl reaction

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Chinese Chemical Letters 2015年第8期26卷 1016-1018页

作者： Yang-Qiu Peng lai-chun Luo Jiao Gong Jian Huang Qi Sun State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University

The potentially bioactive 2-aryl-thiazolo[4,5-b]pyridines were synthesized via palladium-catalyzed desulfitative cross-coupling reaction between multisubstituted thiazolo[4,5-b]pyridine thioethers and boronic acids. Y... 详细信息

关键词： palladium catalyzed pyridine carboxylate reserved potentially Srogl reaction bioactive entries fused

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A dermatoglyphic study of the Amis aboriginal population of Taiwan

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Science China(Life Sciences) 2008年第1期51卷 80-85页

作者： CHEN Yao-Fong ZHANG HaiGuo SHEN Chien-Fu lai chun-Hung Institute of Human Development Tzu Chi UniversityHualienTaiwan 970-74China Department of Medical Genetics School of MedicineShanghai Jiao Tong UniversityShanghai 200025China

Amis is the largest aboriginal population in Taiwan. The previous dermatoglyphic studies of the Amis only reported limited data. In this study, we collected and analyzed the dermatoglyphs of 200 Amis in-dividuals, and we reported a wide range of dermatoglyphic variables including total finger ridge count, a-b ridge count, atd angle, axial triradius percent distance, and frequencies of fingerprint pattern, pal-mar thenar pattern, palmar interdigital pattern, and simian line. This study is the first comprehensive dermatoglyphic research of Amis since 1960s, and its dermatoglyphic data will be useful for future re-search in anthropology, genetics and medicine.

关键词： Gaoshan Amis Taiwan aborigines dermatoglyphics anthropology

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Downside of a carbon tax for environment:Impact of information sharing

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Advances in Climate Change Research 2020年第2期11卷 92-101页

作者： NIE Jia-Jia SHI chun-lai XIONG Yu XIA Sen-Mao LIANG Jia-Min School of Economics and Management Southwest Jiaotong UniversityChengdu610031China Surrey Business School University of SurreyGuilfordGU27XHUK Business School Coventry UniversityCoventryCV15FBUK Newcastle Business School Northumbria UniversityNewcastleNE18STUK

Motivated by the observation that firms invest in carbon emissions reduction to decrease the cost of carbon tax as governments in numerous countries increasingly implement carbon tax to improve the environment,and broad researcher and practitioner agreement that carbon tax implementation always benefits the ***,we find that a carbon tax may actually hurt the environment based on a stylized game model with a better-informed retailer(one who controls the demand information sharing with the manufacturer)and a *** particular,we find that the carbon emissions reduction may harm the environment if the carbon tax is moderate or both the carbon tax and the demand fluctuation are *** further reveal free-riding behavior by the retailer,who may enjoy more profit sharing from the supply chain in the presence of carbon emissions *** on these observations,we argue that a carbon tax does not always benefit the environment when a manufacturer who receives demand information from the retailer responds better to market uncertainty.

关键词： Supply chain management Carbon emissions reduction Carbon tax Information sharing

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Effects of Nitrogen Application on Chlorophyll Fluorescence Parameters and Leaf Gas Exchange in Naked Oat

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Journal of Integrative Agriculture 2013年第12期12卷 2164-2171页

作者： LIN Ye-chun HU Yue-gao REN Chang-zhong GUO lai-chun WANG chun-long JIANG Ying WANG Xue-jiao Phendukani Hlatshwayo ZENG Zhao-hai College of Agronomy and Biotechnology China Agricultural University Baicheng Academy of Agricultural Sciences KZN Department of Agriculture

Naked oat（Avena nuda L.） was originated from China,where soil nitrogen（N） is low *** responses of chlorophyll（Chl.） fluorescence parameters and leaf gas exchange to N application were analysed in this *** the N application rate ranged from 60 to 120 kg ha-1,variable fluorescence（F v）,the maximal fluorescence（F m）,the maximal photochemical efficiency（F v /F m）,quantum yield（Φ PS II） of the photosynthetic system II（PS II）,electron transport rate（ETR）,and photochemical quenching coefficient（qP） increased with N application level,however,non-photochemical quenching coefficient（qN） ***,there was no difference in initial fluorescence（F o） with further more N *** maximum net photosynthetic rate（P max）,apparent dark respiration rate（R d） and light saturation point（LSP） were improved with 40-56 kg N ha-1as basal fertilizer and 24-40 kg N ha-1as top dressing fertilizer applied at jointing *** quantum yield（α） was decreased with 24 kg N ha-1as basal fertilizer and 56 kg N ha-1as top dressing ***-leaf net photosynthetic rate（P n） was significantly enhanced at the jointing and heading stages with 40-56 kg N ha-1as basal fertilizer; in addition,increased at grain filling stage of naked oat with 40-56 kg N ha-1as top dressing fertilizer.90 kg N ha-1（50-70% as basal fertilizer and 30-50% as top dressing fertilizer） application is recommended to alleviate photodamage of photosystem and improve the photosynthetic rate in naked oat.

关键词： Avena nuda nitrogen fertilizer nitrogen application chlorophyll fluorescence gas exchange

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Data processing and error analysis for the CE-1 Lunar microwave radiometer

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Research in Astronomy and Astrophysics 2013年第3期13卷 359-372页

作者： Jian-Qing Feng Yan Su Jian-Jun Liu Yong-Liao Zou chun-lai Li National Astronomical Observatories Chinese Academy of Sciences

The microwave radiometer （MRM） onboard the Chang＇ E-1 （CE-I） lu- nar orbiter is a 4-frequency microwave radiometer, and it is mainly used to obtain the brightness temperature （TB） of the lunar surface, from which the thickness, temperature, dielectric constant and other related properties of the lunar regolith can be derived. The working mode of the CE-1 MRM, the ground calibration （including the official calibration coefficients）, as well as the acquisition and processing of the raw data are introduced. Our data analysis shows that TB increases with increasing frequency, decreases towards the lunar poles and is significantly affected by solar illumination. Our analysis also reveals that the main uncertainty in TB comes from ground calibration.

关键词： space vehicles -- instruments: microwave radiometer -- Moon: bright-ness temperature -- method: data processing -- error analysis

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Design of Waveguide Integrated Ge-Quantum-Well Electro-Absorption Modulators

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Chinese Physics Letters 2011年第1期28卷 102-105页

作者： ZHAO Hong-Wei HU Wei-Xuan XUE chun-lai CHENG Bu-Wen WANG Qi-Ming State Key Laboratory of Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083

We present two designs for a waveguide Oe-quantum-well electro-absorption modulator. In our designs, the strip SOI waveguides are butt-coupled and evanescent-coupled to the modulator, respectively. The proposed Gequantum-weB electro-absorption modulator is based on quantum-confined Stark effect （QCSE）, having a 3-dB bandwidth above 50GHz, as well as a low switching power （around 60fJ/bit at 1435nm）. In the butt-coupled design, the optimized extinction ratio is up to 11.4 dB, while the insertion loss is only 6. 74 dB. For the second one, which utilizes evanescent coupling, the extinction ratio and insertion loss are 9.18 dB and 6. 72 dB, respectively.

关键词： Optics quantum optics and lasers

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A Repressor in 5′-UTR of hKv4.3 Gene

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Chemical Research in Chinese Universities 2006年第2期22卷 197-200页

作者： LI Hao JIANG chun-lai YU Xiang-hui WU Yong-ge LI Wei KONG Wei College of Life Science Jilin University Changchun 130012 P. R. China Jilin Teacher＇s Institute of Engineering Technology Changchun 130052 P. R. China

The effect of repressors on ion channel gene expression was studied. The hKv4. 3 promoter and the sequence （＋ 2-- ＋ 160, S160） of 5＇-UTR of the hKv4. 3 gene was cloned into the pβ-gal-Basic vector. The transient expression of the pβ-gal vector and the analysis of the relative activity of β-galactosidase were carried out. The analysis of the mRNA level was carried out with the RT-PCR method. S160 could intensively repress the expression of the hKv4. 3 gene with position-specificity. The level of mRNA did not alter obviously. A repressor（ S160）, in 5＇-UTR of the hKv4. 3 gene was found and its repression to gene expression may play a role in the post-transcription process.

关键词： hKv4. 3 gene Repressor

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