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Morphology and structure of BzK-selected galaxies at z ～ 2 in the CANDELS-COSMOS field

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Research in Astronomy and Astrophysics 2015年第6期15卷 819-827页

作者： guan-wen Fang Zhong-Yang Ma Yang Chen Xu Kong Institute for Astronomy and History of Science and Technology Dali University Key Laboratory for Research in Galaxies and Cosmology University of Science and Technology of China Chinese Academy of Sciences Center for Astrophysics University of Science and Technology of China SISSA via Bonomea 265 I-34136 Trieste Italy

Utilizing a BzK-selecfion technique, we obtain 14 550 star-forming galaxies （sBzKs） and 1763 passive galaxies （pBzKs） at z - 2 from the K-selected （KAB 〈 22.5） catalog in the COSMOS/UltraVISTA field. The differential number counts of sBzKs and pBzKs are consistent with the results from the literature. Compared to the observed results, semi-analytic models of galaxy formation and evolution provide too few （many） galaxies at the high （low） mass end. Moreover, we find that the star formation rate and stellar mass of sBzKs follow the relation of the main sequence. Based on HST/Wide Field Camera 3 F160W imaging, we find a wide range of morphological diversities for sBzKs, from diffuse to early-type spiral structures, with relatively high M20, large size and low G, while pBzKs have elliptical-like compact morphologies with lower M20, smaller size and higher G, indicating a more concentrated and symmetric spatial extent of stellar population distribution in pBzKs than sBzKs. Furthermore, the sizes of pBzKs （sBzKs） at z - 2 are on average two to three （one to two） times smaller than those of local early-type （late-type） galaxies with similar stellar mass. Our findings imply that the two classes have different evolution models and mass assembly histories.

关键词： galaxies evolution -- galaxies fundamental parameters -- galaxies structure -- galaxies high-redshift

Morphology and structure of extremely red objects at z ～ 1 in the CANDELS-COSMOS field

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Research in Astronomy and Astrophysics 2015年第6期15卷 811-818页

Using high-resolution HST/Wide Field Camera 3 F125W imaging from the CANDELS-COSMOS field, we report the structural and morphological properties of extremely red objects （EROs） at -z 1. Based on the UVJ color criteria, we sepa- rate EROs into two types： old passive galaxies （OGs） and dusty star-forming galaxies （DGs）. For a given stellar mass, we find that the mean size of OGs （DGs） is smaller by a factor of - 2 （1.5） than that of present-day early-type （late-type） galaxies at a rest-frame optical wavelength. We derive the average effective radii of OGs and DGs, corresponding to 2.09 ± 1.13 kpc and 3.27± 1.14 kpc, respectively. Generally, the DGs are heterogeneous, with mixed features including bulges, disks and irregular structures, with relatively high M20, large size and low G. By contrast, OGs have elliptical-like compact morphologies with lower M20, smaller size and higher G, indicating a more concentrated and symmetric spatial extent of the stellar population distribution in OGs than DGs. These findings imply that OGs and DGs have different evolutionary processes, and that the minor merger scenario is the most likely mechanism for the structural properties of OGs. However, the size evolution of DGs is possibly due to the secular evolution of galaxies.

关键词： galaxies evolution -- galaxies: fundamental parameters -- galaxies structure -- galaxies high-redshift

Preparations of TiO_2 film coated on foam nickel substrate by sol-gel processes and its photocatalytic activity for degradation of acetaldehyde

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Journal of Environmental Sciences 2007年第1期19卷 80-85页

作者： HU Hai XIAO wen-jun YUAN Jian SHI Jian-wei CHEN Ming-xia SHANG guan wen-feng Research Center for Combustion and Environment Technology Shanghai Jiao Tong University. Shanghai 200030 China

Anatase TiO2 films were successfully prepared on foam nickel substrates by sol-gel technique using tetrabutyl titanate as precursor. The characteristics of the TiO2 films were investigated by XPS, XRD, FE-SEM, TEM and UV-Vis absorption spectra. The photocatalytic activities of TiO2 films were investigated by photocatalytic degradation reactions of gaseous acetaldehyde, an indoor pollutant, under ultraviolet light irradiation. It was found that Ni^2＋ doping into TiO2 films due to the foam nickel substrates resulted in the extension of absorption edges of TiO2 films from UV region to visible light region. The pre-heating for foam nickel substrates resulted in the formation of NiO layer, which prevented effectively the injection of photogenerated electrons from TiO2 films to metal nickel. The TiO2 films displayed high photocatalytic activity for the degradation of acetaldehyde, and were enhanced by calcining the substrates and coating TiO2 films repeatedly. The high activity was mainly attributed to the improvement of the characteristics of substrate surface and the increase of active sites on photocatalyst.

关键词： photocatalyst TiO2 films foam nickel sol-gel acetaldehyde degradation

Oscillation properties of matter–wave bright solitons in harmonic potentials

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Chinese Physics B 2022年第8期31卷 317-324页

作者： Shu-wen guan Ling-Zheng Meng Li-Chen Zhao School of Physics Northwest UniversityXi’an 710127China NSFC–SPTP Peng Huanwu Center for Fundamental Theory Xi’an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi’an 710127China

We investigate the oscillation periods of bright soliton pair or vector bright soliton pair in harmonic potentials. We demonstrate that periods of low-speed solitons are greatly affected by the position shift during their collisions. The modified oscillation periods are described by defining a characterized speed, with the aid of asymptotic analysis on related exact analytic soliton solutions in integrable cases. The oscillation period can be used to distinguish the inter-and intra-species interactions between solitons. However, a bright soliton cannot oscillate in a harmonic trap, when it is coupled with a dark soliton(without any trapping potentials). Interestingly, it can oscillate in an anti-harmonic potential, and the oscillation behavior is explained by a quasi-particle theory. The modified period of two dark-bright solitons can be also described well by the characterized speed. These results address well the effects of position shift during soliton collision, which provides an important supplement for previous studies without considering phase shift effects.

关键词： matter–wave bright soliton harmonic potential oscillation period

Difference in normal corneal thickness and curvature between Mongolian and Han nationalities

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International Journal of Ophthalmology(English edition) 2015年第2期8卷 399-402页

作者： Hai-Xia Zhao Li Zhang wen-Ying guan Department of Ophthalmology the Affiliated Hospital of Inner Monogolia Medical University

AIM: To investigate the differences in central corneal thickness(CCT) and curvature in myopic patients with different genders between Mongolian and Han nationalities in the Inner Mongolia ***: Patients with myopia, among whom 122cases(244 eyes) were Mongolian and 150 cases(300eyes) were Han, were selected. Pentacam was used to measure the corneal curvature, whereas CCT was determined by Pentacam, Orbscan and ultrasound ***: Comparisons of the curvature of men and women in Mongolia showed a significant difference(P <0.05) by comparing of the CCT values measured by three methods in Han and Mongolian in Inner Mongolia, we can draw a conclusion that the CCT values measured by Pentacam are less than the values by Orbscan and ultrasound pachymetry, and there are statistically significant difference in CCT measurement among the instruments except between the Orbscan and ultrasound pachymetry. The CCT values of Mongolians are more than Han people, and the analysis exhibited statistical significance. The CCT values measured by Orbscan in Mongolia of women are more than men, the difference showed statistical ***: Corneal curvature in Mongolian females was significantly higher than that in males. However, no significant difference was observed among Han males and females. The CCT values of Mongolian females were higher than those of males. The normal CCT values measured by Pentacam in Mongolian myopic patients were smaller than those obtained by Orbscan or ultrasound. The normal CCT values of Mongolian patients with myopia were higher than those reported for domestic people.

关键词： pentacam orbscan mongolian nationality Han nationality gender central corneal thickness

Is it necessary to use the entire root as a donor when transferring contralateral C7 nerve to repair median nerve？

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Neural Regeneration Research 2018年第1期13卷 94-99页

作者： Kai-ming Gao Jie Lao wen-jie guan Jing-jing Hu Department of Hand Surgery Huashan Hospital Fudan University Shanghai China Key Laboratory of Hand Reconstruction Ministry of Health Shanghai China Shanghai Key Laboratory of Peripheral Nerve and Microsurgery Shanghai China Nursing Department Huashan Hospital Fudan University Shanghai China

If a partial contralateral C7 nerve is transferred to a recipient injured nerve, results are not satisfactory. However, if an entire contralateral C7 nerve is used to repair two nerves, both recipient nerves show good recovery. These findings seem contradictory, as the above two methods use the same donor nerve, only the cutting method of the contralateral C7 nerve is different. To verify whether this can actually result in different repair effects, we divided rats with right total brachial plexus injury into three groups. In the entire root group, the entire contralateral C7 root was transected and transferred to the median nerve of the affected limb. In the posterior division group, only the posterior division of the contralateral C7 root was transected and transferred to the median nerve. In the entire root ＋ posterior division group, the entire contralateral C7 root was transected but only the posterior division was transferred to the median nerve. After neurectomy,the median nerve was repaired on the affected side in the three groups. At 8, 12, and 16 weeks postoperatively, electrophysiological examination showed that maximum amplitude, latency, muscle tetanic contraction force, and muscle fiber cross-sectional area of the flexor digitorum superficialis muscle were significantly better in the entire root and entire root ＋ posterior division groups than in the posterior division group. No significant difference was found between the entire root and entire root ＋ posterior division groups. Counts of myelinated axons in the median nerve were greater in the entire root group than in the entire root ＋ posterior division group, which were greater than the posterior division group. We conclude that for the same recipient nerve, harvesting of the entire contralateral C7 root achieved significantly better recovery than partial harvesting, even if only part of the entire root was used for transfer. This result indicates that the entire root should be used as a dono

关键词： nerve regeneration peripheral nerve injury brachial plexus injury avulsion injury contralateral C7 transfer nerve root entire root partial root median nerve ulnar nerve animal experiment neural regeneration

Is the W-boson mass enhanced by the axion-like particle,dark photon,or chameleon dark energy?

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Science China(Physics,Mechanics & Astronomy) 2022年第12期65卷 145-152页

作者： guan-wen Yuan Lei Zu Lei Feng Yi-Fu Cai Yi-Zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei230026China Department of Astronomy School of Physical SciencesUniversity of Science and Technology of ChinaHefei230026China CAS Key Laboratory for Researches in Galaxies and Cosmology University of Science and Technology of ChinaHefei230026China

The W-boson mass(m W=(80.4335±0.0094)Ge V)measured by the Collider Detector at Fermilab Collaboration is greater than the standard model(SM)prediction at a confidence level of 7σ,strongly suggesting the presence of new particles or *** the literature,various new particles and/or fields have been introduced to explain the astrophysical and experimental data,and their presence,in principle,may also enhance the W-boson *** this study,we investigate axion-like particle(ALP),dark photon(DP),and chameleon dark energy(DE)models for a solution to the W-boson mass *** find that the ALP and DP interpretations have been significantly narrowed down by global electroweak *** possibility of attributing the W-boson mass anomaly to the chameleon DE is ruled out by other experiments.

关键词： W-boson mass axion-like particle dark photon chameleon dark energy

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Facile synthesis of metal-organic frameworks embedded in interconnected macroporous polymer as a dual acid-base bifunctional catalyst for efficient conversion of cellulose to 5-hydroxymethylfurfural

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Chinese Journal of Chemical Engineering 2022年第4期35卷 169-181页

作者： Yanan Wei Yunlei Zhang Bing Li wen guan Changhao Yan Xin Li Yongsheng Yan Institute of Green Chemistry and Chemical Technology School of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang 212000China Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang 212000China

5-Hydroxymethylfurfural(5-HMF),as a key platform compound for the conversion of biomass to various biomass-derived chemicals and biofuels,has been attracted extensive *** this research,using Pickering high internal phase emulsions(Pickering HIPEs)as template and functional metal-organic frameworks(MOFs,UiO-66-SO;H and UiO-66-NH;)/Tween 85 as co-stabilizers to synthesis the dual acid-base bifunctional macroporous polymer catalyst by one-pot process,which has excellent catalytic activity in the cascade reaction of converting cellulose to *** effects of the emulsion parameters including the amount of surfactant(ranging from 0.5%to 2.0%(mass)),the internal phase volume fraction(ranging from 75%to 90%)and the acid/base Pickering particles mass ratio(ranging from 0:6 to 6:0)on the morphology and catalytic performance of solid catalyst were systematically *** results of catalytic experiments suggested that the connected large pore size of catalyst can effectively improve the cellulose conversion,and the synergistic effect of acid and base active sites can effectively improve the 5-HMF *** highest 5-HMF yield,about 40.5%,can be obtained by using polymer/MOFs composite as catalyst(Poly-P12,the pore size of(53.3±11.3)μm,the acid density of 1.99 mmol·g^(-1)and the base density of 1.13 mol·g^(-1))under the optimal reaction conditions(130℃,3 h).Herein,the polymer/MOFs composite with open-cell structure was prepared by the Pickering HIPEs templating method,which provided a favorable experimental basis and theoretical reference for achieving efficient production of high addedvalue product from abundant biomass.

关键词： Catalyst Biomass Hydrolysis 5-Hydroxymethylfurfural Pickering high internal phase emulsions templated polymer Acid-base bifunctional site

Narrative Study on Witnesses1 Involvement in Their Statements

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Journal of Forensic Science and Medicine 2018年第1期4卷 31-39页

作者： wen guan Sr.Luping Zhang Department of English School of Foreign LanguagesChina University of Political Science and LawBeijingChina

The present study,based on Labov's narrative theory,focuses on how witnesses,involvement affects their narrative reconstruction of the criminal ***5 involvement is first subcategorized,and there are two circumstances concerning their involvements,one being single suspect versus victim(s)crime and the other multiple suspects versus victim(s)*** present study takes four witness statements from a single suspect malicious injury case as data to further analyze the effects exerted by different witness involvements on witness statements and their corresponding *** of the analysis indicate that how witnesses are involved in the criminal event exert different effects on witness statements in three aspects as follows:narrative structure,participant distribution,and language *** results of this study further revealed that the more legal responsibility a witness is likely to take for the criminal event,the more transformations he would make in his narrative reconstruction of the crime.

关键词： Language strategy narrative participant distribution witness statements witnesses'involvement