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A parametric bootstrap approach for one-way classification model with skew-normal random effects

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Applied Mathematics(A Journal of Chinese Universities) 2019年第4期34卷 423-435页

作者： YE Ren-dao xu li-jun LUO Kun JIANG ling School of Economics Hangzhou Dianzi UniversityHangzhou 310018China Alibaba Business College Hangzhou Normal UniversityHangzhou 310016China

In this paper,several properties of one-way classification model with skew-normal random effects are obtained,such as moment generating function,density function and noncentral skew chi-square distribution,*** on the EM algorithm,we discuss the maximum likelihood(ML)estimation of unknown *** testing problem of fixed effect,a parametric bootstrap(PB)approach is ***,some simulation results on the Type I error rates and powers of the PB approach are obtained,which show that the PB approach provides satisfactory performances on the Type I error rates and powers,even for small *** illustration,our main results are applied to a real data problem.

关键词： parametric bootstrap EM algorithm one-way classification model skew-normal distribution skew chi-square distribution

Glacier changes since the early 1960s, eastern Pamir, China

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Journal of Mountain Science 2016年第2期13卷 276-291页

作者： ZHANG Zhen xu jun-li liU Shi-yin GUO Wan-qin WEI jun-feng FENG Tong State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of Sciences Beijing 100049 China

Glaciers in the eastern Pamir are important for water resources and the social and economic development of the *** the last 50 years,these glaciers have shrunk and lost ice mass due to climate *** order to understand recent glacier dynamics in the region,a new inventory was compiled from Landsat TM/ETM+ images acquired in2009,free of clouds and with minimal snow cover on the glacierized *** first glacier inventory of the area was also updated by digitizing glacier outlines from topographical maps that had been modified and verified using aerial *** glacier area decreased by 10.8%±1.1%,mainly attributed to an increase in air temperature,although precipitation,glacier size and topographic features also combined to affect the general shrinkage of the *** 19.3–21.4 km^3 estimated glacier mass loss has contributed to an increase in river runoff and water resources.

关键词： Glacier change Glacier inventory Eastern Pamir Remote sensing Mass loss

Synthesis,Characterization and Standard Molar Formation Enthalpy of [Sm(C_7H_5O_3)_2(C_4H_6NO_2S)]·2H_2O

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Chemical Research in Chinese Universities 2009年第4期25卷 564-568页

作者： li xu YANG De-jun li Qiang-guo li Ai-tao YE li-juan JIANG Jian-hong Department of Chemistry and life Science Xiangnan University Chenzhou 423000 P. R. China

[Sm（C7H5O3）2（C4H6NO2S）]·2H2O was synthesized from the reaction of samarium chloride hexahydrate with salicylic acid and thioproline,and characterized by IR,elemental analysis and thermogravimatric *** standard molar enthalpies of the solutions of SmCl3·6H2O（s）,2[C7H6O3（s）],[C4H7NO2S（s）] and [Sm（C7H5O3）2·（C4H6NO2S）·2H2O（s）] in a mixed solvent of absolute ethyl alcohol,dimethyl formamide（DMF） and 3 mol/L HCl were,respectively,determined by calorimetry to be ΔsHm^Θ [SmCl3·6H2O（s）,298.15 K]=（-46.68±0.15） kJ/mol,ΔsHm^Θ [2C7H6O3（s）,298.15 K]=（25.19±0.02） kJ/mol,ΔsHm^Θ [C4H7NO2S（s）,298.15 K]=（16.20±0.17） kJ/mol and ΔsHm^Θ {[Sm（C7H5O3）2（C4H6NO2S）]·2H2O（s）,298.15 K}=（-81.24±0.67） kJ/*** enthalpy change of the reaction SmCl3·6H2O（s）＋2C7H6O3（s）＋C4H7NO2S（s）=[Sm（C7H5O3）2（C4H6NO2S）]·2H2O（s）＋3HCl（g）＋4H2O（l） was determined to be ΔrHm^Θ =（123.45±0.71） kJ/*** the data in the literature,the standard molar formation enthalpy of [Sm（C7H5O3）2（C4H6NO2S）]·2H2O（s） was estimated to be Δf Hm^Θ {[Sm（C7H5O3）2（C4H6NO2S）]·2H2O（s）,298.15 K}=（-2912.03±3.1） kJ/mol through Hess＇ law.

关键词： Samarium chloride hexahydrate Salicylic acid Thioproline Standard molar formation enthalpy

Mass Loss from Glaciers in the Chinese Altai Mountains between 1959 and 2008 Revealed Based on Historical Maps, SRTM, and ASTER Images

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Journal of Mountain Science 2015年第2期12卷 330-343页

作者： WEI jun-feng liU Shi-yin xu jun-li GUO Wan-qin BAO Wei-jia SHANGGUAN Dong-hui JIANG Zong-li State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences University of Chinese Academy of Sciences Department of Geography University of Zürich Hunan Province Key Laboratory of Coal Resources Clean-Utilization and Mine Environment Protection Hunan University of Science and Technology

Mass loss of glaciers in the Chinese Altai was detected using geodetic methods based on topographical maps(1959), the Shuttle Radar Topography Mission(SRTM) Digital Elevation Model(DEM)(2000), and the Advanced Space-borne Thermal Emission and Reflection Radiometer(ASTER) stereo images(2008). The results indicate that a continued and accelerating shrinkage has occurred in the Chinese Altai Mountains during the last 50 years, with mass deficits of 0.43 ± 0.02 and0.54 ± 0.13 m a-1 water equivalent(w.e.) during the periods 1959-1999 and 1999-2008, ***, the Chinese Altai Mountains have lost 7.06 ±0.44 km3 in ice volume(equivalent to-0.43 ± 0.03 m a-1 w.e.) from 1959-2008. The spatial heterogeneity in mass loss was potentially affected by comprehensive changes in temperature and precipitation, and had a substantial correlation withglacier size and topographic settings. Comparison shows that in the Chinese Altai Mountains glaciers have experienced a more rapid mass loss than those in the Tianshan and northwestern Tibetan Plateau(TP), and the mass balance of glaciers was slightly less negative relative to those in the Russian Altai, Himalaya, and southern TP.

关键词： Altai Mountains Geodetic method Glacier change Mass balance

Glacier change in the western Nyainqentanglha Range,Tibetan Plateau using historical maps and Landsat imagery:1970-2014

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Journal of Mountain Science 2016年第8期13卷 1358-1374页

作者： WU Kun-peng liU Shi-yin GUO Wan-qin WEI jun-feng xu jun-li BAO Wei-jia YAO Xiao-jun State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of ScienceLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

Glaciers in the western Nyainqentanglha Range are an important source of water for social and economic development. Changes in their area were derived from two Chinese glacier inventories; one from the 197o 1：5o,ooo scale Chinese Topographic Maps series and the other from Landsat TM/ETM＋ images acquired in 2009. Analyses also included boundaries from 2000 and 2014 Landsat TM/ETM＋ images. A continuing and accelerating shrinkage of glaciers occurred here from 1970 to 2014, with glacier area decreasing by 244.38±29.48 km^2 （27.4%±3.3%） or 0.62%±0.08% a^-1. While this is consistent with a changing climate, local topographic parameters, such as altitude, slope, aspect and debris cover, are also important influences. Recession is manifested by a rise in the elevation of the glacier terminus. The shrinkage of glaciers with NE, N and NW orientations exceeded that of other aspects, and glaciers with SE and S orientations experienced less shrinkage. Changes in the average positive difference of glaciation （PDG） show that the western Nyainqentanglha Range has unfavorable conditions for glacier maintenance which is being exacerbated by a warming climate since 1970.

关键词： Glacier change Glacier inventory Western Nyainqentanglha Range Remote sensing

Reduction of VOC emissions by a membrane-based gas absorption process

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Journal of Environmental Sciences 2009年第8期21卷 1096-1102页

作者： li Rui, xu jun, WANG lianjun, li Jiansheng, SUN Xiuyun School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China. [a]School of Chemical Engineering Nanjing University of Science and Technology Nanjing 210094 China. E-mail: drbeaneyes@***

A membrane-based gas absorption （MGA） process was evaluated for the removal of volatile organic compounds （VOCs） based on C6H6/N2 mixture. The absorption of C6H6 from a C6H6/N2 mixture was investigated using a hydrophobic polypropylene hollow fiber membrane contactor and the aqueous solution of N-formyl morpholine （NFM） as absorbent. The effects of various factors on the overall mass transfer coefficient was investigated. The experimental results showed that the removal efficiency of C6H6 could reach 99.5% in present studied system. A mathematical model based on resistance-in-series concept was presented to predict the value of overall mass transfer coefficient. The average error between the predicted and experimental values is 7.9%. In addition, conventional packed columns for VOCs removal was also evaluated for comparison.

关键词： VOCs removal membrane contactor membrane-based gas absorption mass transfer model

Case Report:Subglottic adenoid cystic carcinoma mistaken for asthma

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第9期10卷 707-710页

作者： Hua-lin WANG lin xu Fu-jun li Department of Otorhinolaryngology the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China

Adenoid cystic carcinoma rarely occurs within the subglottic larynx. In this study, a case of subglottic adenoid cystic carcinoma was reported. A 54 year-old Chinese woman developed a sudden onset of chest distress and cough worsening after physical exertion, and was diagnosed with, and treated as, bronchial asthma. Regular anti-asthmatic therapy did not improve the symptoms. Until a sudden dyspnea, a cervicothoracic computerized tomography （CT） revealed that her upper airway was obstructed by a laryngeal tumor. The patient was diagnosed with a subglottic adenoid cystic carcinoma and treated with complete surgical excision and adjuvant radiation therapy. Follow-up endoscopy and laryngeal magnetic resonance imaging （MR1） at six months showed no recurrence of the tumor. The diagnosis of subglottic adenoid cystic carcinoma should be considered in patients who are characterized by dyspnea, cough, and stridor, but do not respond to regular anti-asthmatic therapy.

关键词： Subglottic adenoid cystic carcinoma Larynx Asthma

Application of cathodoluminescence to zircon in FEG-ESEM

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Progress in Natural Science:Materials International 2006年第9期16卷 919-924页

作者： CHEN li , xu jun and SU li (Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China Geology Experimental Center, China University of Geoscience, Beijing 100083, China) [a]Electron Microscopy Laboratory School of Physics Peking University Beijing China [b]Geology Experimental Centre China university of Geoscience. Beijing China

Cathodoluminescence (CL) image analysis of zircon is a key step of mineral micro-area compositional investigation and U-(Th)-Pb dating. We introduce a system consisting of field emission ESEM and high performance cathodoluminescence. This system has obvious advantages in imaging resolution and CL spectrum. We acquired some zircon CL images and spectra to demonstrate the ability of this system. Our results show that this system has a great potential application to characterize and identify the genesis of zircon.

关键词： zircon cathodoluminescence ESEM.

L-type calcium channel blockers enhance 5-HTP-induced antinociception in mice

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Acta Pharmacologica Sinica 2004年第5期25卷 102-108页

作者： Jian-hui liANG1, jun-xu li, xu-hua WANG, Bi CHEN, Ying LU, Pan ZHANG, Rong HAN, Xiang-feng YEDepartment of Neuropharmacology, National Institute on Drug Dependence, Peking University, Beijing 100083, China Department of Neuropharmacology National Institute on Drug Dependence Peking University Beijing 100083 China

AIM: To investigate the involvement of L-type Ca2+ channels in antinociceptive action induced by the 5-HT precursor,5-hydroxytryptophan (5-HTP). METHODS: Female Kunming mice were treated with either 5-HTP (20-80 mg/kg,ip) alone, or the combination of 5-HTP and fluoxetine (2-8 mg/kg, ip), pargyline (15-60 mg/kg, ip), nimodipine (2.5-10 mg/kg, ip), nifedipine (2.5-10 mg/kg, ip), verapamil (2.5-10 mg/kg, ip), CaCl2 (5-20 mmol/L, icv), or EGTA(0.5-3 mmol/L, icv) prior to the hot-plate test (55 C, hind-paw licking latency). In addition, locomotor activity inmice treated with 5-HTP alone was measured using an ambulometer with five activity boxes. RESULTS: Ipinjection of 5-HTP alone had no influence on the spontaneous locomotor activity, whereas dose-dependently in-creased the latency to licking hind-paw in the hot-plate test in mice. The inhibitory effects of 5-HTP on nociceptiveresponse were significantly enhanced by fluoxetine in the mouse hot-plate test. At a sub-effective dose, pargylinecould cause a leftward shift in the dose-response curve of 5-HTP-induced antinociception. Co-administration with5-HTP and nimodipine, nifedipine, or verapamil obviously potentiated the antinociceptive effects elicited by ***, 5-HTP-induced antinociception was antagonized by CaCl2 and enhanced by EGTA injected icv in themouse hot-plate test. CONCLUSION: These findings suggest that systemic administration of 5-HTP may yield theantinociceptive effects, which are related to Ca2+ influx from extracellular fluid through L-type Ca2+ channels.

关键词： serotonin 5-hydroxytryptophan fluoxetine pargyline calcium channel blockers pain measure-ment