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Effects of humic acid coatings on phenanthrene sorption to black carbon

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Journal of Environmental Sciences 2007年第10期19卷 1189-1192页

作者： WU Cheng ZHANG xiao-li li Guan-bin School of Chemistry and Chemical Engineering Shandong University Jinan 250100 China Shandong Agro-Environment Protection Station Jinan 250100 China

Black carbon （BC） can strongly adsorb hydrophobic organic compounds （HOCs）. The HOC sorption to coated BC could be attenuated in soil and sediment compared with that of the parent BC. To study the potential causes of the sorption attenuation, humic acid （HA） and BC were isolated. Phenanthrene （PHE） was selected as the representative of HOCs. BC was coated with the precipitated HA. The PHE sorption to the HA-coated BC was determined. The HA coatings on BC could result in the significant sorption attenuation of PHE to BC. The attenuation varied in different HA origin and was positively correlated to the aromaticity of HA. The attenuation could be explained by the direct competition between HA and PHE for the available sorption sites on BC and the reduction of the available sorption sites as a result of the pore blockage of BC caused by the HA coatings. Therefore, the HA coatings on BC was one potential cause of the attenuation of HOC sorption to BC in soil and sediment.

关键词： black carbon humic acid phenanthrene sorption attenuation

Masses and Widths of light Scalar Mesons in Chiral Perturbation Theory

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Communications in Theoretical Physics 2008年第2期49卷 451-455页

作者： CHEN xiao-Zhao li xiao-Ya LU xiao-Fu Department of Physics Sichuan University Chengdu 610064 China Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China China Center of Advanced Science and Technology （World Laboratory） Beijing 100080 China

Based on the diquark model, we assume that the light scalar mesons are q^2q^-2 states rather than qq^-. The chiral effective Lagrangian for the light scalar meson is constructed, and the mass relations are obtained： the isotriplet （a0） and the isosinglet （f0） are the heaviest and are degenerate, the isodoublets （κ） are heavier and the other isosinglet （σ） is the lightest; and 2Mκ^2 = Mα0^2＋ Mσ^2. Using experimental value for a0 and σ mass, we obtain Mκ=794 MeV, which is consistent with the experimental value. Then taking Г（a0^0 →ηπ^0） = 90 MeV and Г（f0→π^0π^0） = 20 MeV, we get the width of σ is： Г（σ0→π^＋π^-）= 150 MeV.

关键词： scalar meson honer diquark model chiral perturbation theory

Non-human Primate Models for Brain Disorders – Towards Genetic Manipulations via Innovative Technology

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Neuroscience Bulletin 2017年第2期33卷 247-250页

作者： Zilong Qiu xiao li Institute of Neuroscience Key Laboratory of Primate Neurobiology State Key Laboratory of Neuroscience Center for Excellence in Brain Science and Intelligence TechnologyShanghai Institute for Biological Sciences Chinese Academy of Sciences

Modeling brain disorders has always been one of the key tasks in neurobiological studies. A wide range of organisms including worms, fruit ？ies, zebra？sh, and rodents have been used for modeling brain disorders. However,whether complicated neurological and psychiatric symptoms can be faithfully mimicked in animals is still *** this review, we discuss key ？ndings using non-human primates to address the neural mechanisms underlying stress and anxiety behaviors, as well as technical advances for establishing genetically-engineered non-human primate models of autism spectrum disorders and other *** the close evolutionary connections and similarity of brain structures between non-human primates and humans, together with the rapid progress in genome-editing technology, non-human primates will be indispensable for pathophysiological studies and exploring potential therapeutic methods for treating brain disorders.

关键词： Non-human primates Brain disorders Genome editing Autism Neurological disorders Psychiatric disorders

‘‘Complexation–precipitation'' metal separation method system and its application in secondary resources

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Rare Metals 2014年第4期33卷 369-378页

作者： Zuo-Ren Nie li-Wen Ma xiao-li Xi College of Materials Science and Engineering Beijing University of Technology

Recovery processes of secondary resources usually encounter problems because of the diverse com- positions of wastes. To enhance the applicability of tradi- tional hydrometallurgical process toward secondary resources, the adjustment of components is necessary. In traditional hydrometallurgical separation, precipitation and complexation are extensively used. However, their com- bination as a specific metal separation method has not yet been studied in detail. This approach is very promising for solving problems caused by changeable components during recycling processes of secondary resources. This paper reviews the effects of precipitation and complexation in metal separation processes, and a metal separation method system of ＂complexation-precipitation＂ developed to adjust the components of secondary resources is introduced.

关键词： Secondary resources Complexation-precipitation Method system Metal separation

The Microstructure and Thermal Conductivity of Aluminum Nitride Ceramics Sintered at High Pressure with CaC_(2)

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Chinese Physics Letters 2012年第5期29卷 74-76页

作者： li xiao-Lei WANG li-Ying School of Material Science and Engineering Henan Polytechnic UniversityJiaozuo 454010

Aluminum nitride (AIN) ceramics are sintered by high-pressure technology at 5 GPa/30min/1500-1800℃,using aluminum nitride powder produced by direct nitriding methods and CaC_(2) (3wt%) powder as the starting material and sintering additive,*** sample sintered at 1800℃ shows relatively high density (99.09%) and thermal conductivity (113.7 W/(m.K).XRD patterns indicate that there are no obvious impurity phases in the sintered AIN *** of the microstruct ure by SEM shows that the AlN powder grows into full crystal grains with uniform size,the crystal particles are in a regular hexagonal structure,and the grain boundary phases are clean without gas *** results suggest that AIN ceramics sintered with CaC_(2) can achieve the desired microstructure and high thermal conductivity.

关键词： ceramics powder Microstructure

Comparison of cosmological models using standard rulers and candles

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Research in Astronomy and Astrophysics 2016年第5期16卷 125-134页

作者： xiao-Lei li Shuo Cao xiao-Gang Zheng Song li Marek Biesiada Department of Astronomy Beiiing Normal UniversityBeijing 100875China Department of Physics Capital Normal UniversityBeijing 100048China Department of Astrophysics and Cosmology Institute of PhysicsUniversity of SilesiaUniwersytecka 440-007KatowicePoland

In this paper, we used standard rulers and standard candles （separately and jointly） to explore five popular dark energy models under the assumption of the spatial flatness of the Universe. As standard rulers, we used a data set comprised of 118 galactic scale strong lensing systems （individual standard rulers if properly calibrated for the mass density profile） combined with BAO diagnostics （statistical standard ruler）. Type Ia supernovae served as standard candles. Unlike most previous statistical studies involving strong lensing systems, we relaxed the assumption of a singular isothermal sphere （SIS） in favor of its generalization： the power-law mass density profile. Therefore, along with cosmological model parameters, we fitted the power law index and its first derivative with respect to the redshift （thus allowing for mass density profile evolution）. It turned out that the best fitted ~/parameters are in agreement with each other, irrespective of the cosmological model considered. This demonstrates that galactic strong lensing systems may provide a complementary probe to test the properties of dark energy. The fits for cosmological model parameters which we obtained are in agreement with alternative studies performed by other researchers. Because standard rulers and standard candles have different parameter degeneracies, a combination of stan- dard rulers and standard candles gives much more restrictive results for cosmological parameters. Finally, we attempted an analysis based on model selection using information theoretic criteria （AIC and BIC）. Our results support the claim that the cosmological constant model is still best and there is no （at least statistical） reason to prefer any other more complex model.

关键词： (cosmology:) dark energy -- cosmology: observations -- (cosmology:) cosmological param-eters

Error Thresholds in Single-Peak Gaussian Distributed Fitness Landscapes

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Communications in Theoretical Physics 2007年第4X期48卷 763-768页

作者： FENG xiao-li GU Jian-Zhong li Yu-xiao ZHUO Yi-Zhong School of Physical Engineering Zhengzhou University Zhengzhou 450052 Ghina China Institute of Atomic Energy P.O. Box 275(18) Beijing 102413 China

Based on the Eigen and Crow-Kimura models with a single-peak fitness landscape, we propose the fitness values of all sequence types to be Gausslan distributed random variables to incorporate the effects of the fluctuations of the fitness landscapes （noise of environments） and investigate the concentration distribution and error threshold of quasispecies by performing an ensemble average within this theoretical framework. We find that a small fluctuation of the fitness landscape causes only a slight change in the concentration distribution and error threshold, which implies that the error threshold is stable against small perturbations. However, for a sizable fluctuation, quite different from the previous deterministic models, our statistical results show that the transition from quasi-species to error catastrophe is not so sharp, indicating that the error threshold is located within a certain range and has a shift toward a larger value. Our results are qualitatively in agreement with the experimental data and provide a new implication for antiviral strategies.

关键词： quasi-species error threshold Gaussian distributed fitness landscape

Prevalence of pulmonary embolism at autopsy among elderly patients in a Chinese general hospital

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Journal of Geriatric Cardiology 2016年第11期13卷 894-898页

作者： Ji-li YUN xiao-Ying li Medical School of Chinese PLA General Hospital Beijing China Department of Geriatric Cardiology Chinese PLA General Hospital Beijing China

Objectives To investigate the prevalence and characteristics of pulmonary embolism （PE） at autopsy in a Chinese general hospital over a period of 10 years, and to evaluate the antemortem achievement of the prophylaxis, diagnosis, and treatment of PE. Methods All medical records of deaths from the West Branch of the Chinese People＇s liberation Army （PLA） General Hospital were retrospectively re- viewed, for the period of January 1, 2006 to December 31, 2015. Cases in which autopsies had been performed were identified and further analyzed. The numbers and detailed characteristics of patients who had PEs were noted. Prophylactic measures, along with diagnosis and treatment of PE, were recorded, if performed. Results During the 10-year period, 1057 patients died in the study hospital and 278 necrop- sies were performed （autopsy rate： 26.3%）. Nine patients were found to have PE （3.2%）, and in seven of these patients （2.5%）, the PE was considered to be fatal. Embolisms were found in the trunk and bilateral main branches of the pulmonary artery tree in all seven of the fatal PE cases. Right intracardiac thrombosis was detected in five of the nine PE patients （55.6%）. All patients with PE had been hospitalized in medical departments, and only one had undergone surgery during hospitalization. Antemortem prophylaxis was performed in two of the nine PE cases （22.2%）. None of the 9 patients had received a clinical diagnosis of PE before death. Conclusions The incidence of and death rate associated with PE may vary among different races and regions. Continuous monitoring of PE by means of necropsy in certain representative medical institutions is necessary.

关键词： Autopsy Epidemiology Pulmonary embolism

Fast implementation of kernel simplex volume analysis based on modified Cholesky factorization for endmember extraction

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Frontiers of Information Technology & Electronic Engineering 2016年第3期17卷 250-257页

作者： Jing li xiao-run li li-jiao WANG liao-ying ZHAO College of Electrical Engineering Zhejiang University Institute of Computer Application Technology Hangzhou Dianzi University

Endmember extraction is a key step in the hyperspectral image analysis process. The kernel new simplex growing algorithm （KNSGA）, recently developed as a nonlinear alternative to the simplex growing algorithm （SGA）, has proven a promising endmember extraction technique. However, KNSGA still suffers from two issues limiting its application. First, its random initialization leads to inconsistency in final results; second, excessive computation is caused by the iterations of a simplex volume calculation. To solve the first issue, the spatial pixel purity index （SPPI） method is used in this study to extract the first endrnember, eliminating the initialization dependence. A novel approach tackles the second issue by initially using a modified Cholesky fac- torization to decompose the volume matrix into triangular matrices, in order to avoid directly computing the determinant tauto- logically in the simplex volume formula. Theoretical analysis and experiments on both simulated and real spectral data demonstrate that the proposed algorithm significantly reduces computational complexity, and runs faster than the original algorithm.

关键词： Endmember extraction Modified Cholesky factorization Spatial pixel purity index (SPPI) New simplex growingalgorithm (NSGA) Kernel new simplex growing algorithm (KNSGA)