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InfoMat 2024年第2期6卷 99-106页

作者： Tao Jin Long Yang Xinyue Zhang wen li Yanzhong Pei Interdisciplinary Materials Research Center School of Materials Science and EngineeringTongji UniversityShanghaithe People's Republic of China

The crystal-structure symmetry in real space can be inherited in the reciprocal space,making high-symmetry materials the top candidates for thermoelectrics due to their potential for significant electronic band degeneracy.A practical indicator that can quantitatively describe structural changes would help facilitate the advanced thermoelectric material *** face-centered cubic structures,the spatial environment of the same crystallographic plane family is isotropic,such that the distances between the close-packed layers can be derived from the atomic distances within the *** by this,the relationship between inter-and intra-layer geometric information can be used to compare crystal structures with their desired cubic *** close-packed layer spacing was found to be a practical guideline of crystal structure symmetry in IV-VI chalcogenides and I-V-VI_(2) ternary semiconductors,both of which are historically important *** continuous structural evolution toward high symmetry can be described by the layer spacing when temperature or/and composition change,which is demonstrated by a series of pristine and alloyed thermoelectric materials in this *** layerspacing-based guideline provides a quantitative pathway for manipulating crystal structures to improve the electrical and thermal properties of thermoelectric materials.

关键词： phase transition structure manipulation thermoelectric materials x-ray diffraction

A novel method to prepare metal oxide electrode:Spin-coating with thermal decomposition

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Chinese Chemical Letters 2011年第3期22卷 354-357页

作者： Hao Xu wei Yan Cheng li Tang Department of Environmental Science and Technology Xi'an Jiaotong University Xi'an 710049 China

In this work,we propose a new spin-coating method coupling with high thermal decomposition,to prepare the tin-antimony（Sn-Sb） oxide *** character of the spin-coating electrode was compared with the dip-coating electrode through X-ray diffraction（XRD）,scanning electron microscopy（SEM）,accelerated life test,cyclic voltammetry,and electrolytic degradability. The results showed that the spin-coating electrode had a better defined crystal form,a smoother and more compact surface than that of the dip-coating *** time of the spin-coating electrode was determined to be longer than 15 h,and it was less than 2 min for the dip-coating *** characterization analysis showed that the electrolytic degradability of the spin-coating electrode is better than that of the dip-coating electrode.

关键词： Spin-coating Dip-coating Thermal decomposition Electro properties

New Delhi Metallo-β-Lactamase-Mediated Carbapenem Resistance： Origin, Diagnosis, Treatment and Public Health Concern

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Chinese Medical Journal 2015年第14期128卷 1969-1976页

作者： wen-Juan wei Hai-Fei Yang Ying Ye Jia-Bin li Department of Infectious Disease The First Affiliated Hospital of Anhui Medical University Hefei Anhui 230022 China Department of Infectious Disease Chaohu Hospital of Anhui Medical University Hefei Anhui 238000 China Department of Molecular Biology Institute of Bacterium Resistance Anhui Medical University Hefei Anhui 230022 China Anhui Center for Surveillance of Bacterial Resistance. Hefei. Anhui 230022. China

Objective： To review the origin, diagnosis, treatment and public health concern of New Delhi metallo-β-lactamase （NDM）-producing bacteria. Data Sources： We searched database for studies published in English. The database of PubMed from 2007 to 2015 was used to conduct a search using the keyword term ＂NDM and Acinetobacter or Enterobacteriaceae or Pseudomonas aeruginosa.＂ Study Selection： We collected data including the relevant articles on international transmission, testing methods and treatment strategies of NDM-positive bacteria. Worldwide NDM cases were reviewed based on 22 case reports. Results： The first documented case of infection caused by bacteria producing NDM- 1 occurred in India, in 2008. Since then, 13 blaNDM variants have been reported. The rise of NDM is not only due to its high rate of genetic transfer among unrelated bacterial species, but also to human factors such as travel, sanitation and food production and preparation. With limited treatment options, scientists try to improve available therapies and create new ones. Conclusions： In order to slow down the spread of these NDM-positive bacteria, a series of measures must be implemented. The creation and transmission of blaNDM are potentially global health issues, which are not issues for one country or one medical community, but for global priorities in general and for individual wound care practitioners specifically.

关键词： Bacterial Carbapenem Resistance Drug Resistance New Delhi Metallo-β-Lactamase

Time Lags between the 22 and 37 GHz Bursts of 48 Radio-loud AGNs

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Chinese Journal of Astronomy and Astrophysics 2008年第2期8卷 195-203页

作者： wen-Guo Deng Jin-Ming Bai li Zhang Xian Yang National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Physics Department Yunnan University Kunming 650091

Based on the light curves at 22 and 37 GHz from the Metsahovi monitoring program, we investigate the time lags between the two radio bands for 48 radio-loud AGNs. DCF and ZDCF analyses are applied to the data. Our results show that there is a strong correlation between the two radio frequencies for all the sources, with the variations in the light curves at 37 GHz leading the ones at 22 GHz in general. There is no obvious differences between different sub-class AGNs as regards the time lag. In two sources, it was found that the bursts at the lower frequency lead the ones at the higher frequency. One possible explanation is that electron acceleration dominates the light curve until the radiation reaches the maximum. Some sources, such as 3C 273, 3C 279, 3C 345 and 3C 454.3, have good enough data, so we can calculate their lags burst-by-burst. Our calculations show that different outbursts have dif- ferent lags. Some bursts have positive lags, most of bursts have no clear lags, and a few have negative lags. This result means that different bursts are triggered by different mechanisms, and the interpretation for the result involves both an intrinsic and a geometric mechanism. The positive lags are well consistent with the shock model, and we use these lags to calculate the typical magnetic field strength of the radiating region.

关键词： galaxies: active -- galaxies: individual (3C 273 3C 279 3C 345 3C 454.3) --methods: data analysis

Enantioseparation of Racemic Anti-hepatitis New Drug Bicyclol with Crystallization

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Chinese Chemical Letters 2005年第11期16卷 1471-1473页

作者： wei HU Yan li Chun Zhen ZHANG Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050

The enantioseparation of anti-hepatitis new drug （±）-bicyclol was performed by optically active alkaloid. The alcoholic acid, the hydrolysate of bicyclol was reacted with optically active alkaloid, such as brucine, strychnine, quinidine etc., the diastereoisomeric salts were obtained by fractional recrystallization, then separately decomposed and esterified to obtain the two enantiomers of bicyclol. The pharmacological study showed that the effect of （-）-bicyclol was more potent than racemic bicyclol two times and the potency of （＋）-bicyclol was incative.

关键词： (±)-Bicyclol,4,4'-dimethoxy-2,3,2 3'-bis(methylenedioxy)-6-hydroxymethyl-6'-methoxy-carbonyl biphenyl anti-hepatitis resolution.

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

Optimized Separation of Nine Xanthones by Microemulsion Electrokinetic Chromatography

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Chinese Chemical Letters 2002年第9期13卷 877-880页

作者： Tao BO Hu wei liU Ke An li Chemistry Department Peking UniversityBeijing 100871

A microemulsion electrokinetic chromatography method has been firstly used for the separation of the therapeutically important xanthones from Securidaca inappendiculata. The separation of the nine xanthones was systematically optimized with respect to pH, composition of microemulsion, addition of cyclodextrins, applied voltage and column temperature. Baseline separation was successfully achieved for the nine xanthones, which was also compared with that by micellar electrokinetic chromatography.

关键词： Separation xanthones Securidaca inappendiculata microemulsion electrokinetic chromatography micellar electrokinetic chromatography.

Global identification of chemical constituents and rat metabolites of Si-Miao-Wan by liquid chromatography-electrospray ionization/ quadrupole time-of-flight mass spectrometry

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Chinese Journal of Natural Medicines 2017年第7期15卷 550-560页

作者： LU Jin-Jin HU Xue-wen li Ping CHEN Jun State Key Laboratory of Natural Medicines China Pharmaceutical University Nanjing 210009 China

Si-Miao-Wan(SMW), a tradiational Chinese medicinal formula consisting of Atractylodis Rhizoma, Phellodendri Chinensis Cortex, Coicis Semen, and Achyranthis Bidentatae Radix, has been used for the treatment of gout and gouty arthritis for many years. In the present study, a liquid chromatography quadrupole-time-of-flight mass spectrometry(LC-Q-TOF/MS) method was established to identify the multiple constituents of SMW and its metabolites in rat biological samples after oral administration. A total of 48 compounds in SMW, including 21 alkaloids, 12 organic acids, 2 terpenes, 3 lactones, 2 phytosterols, and 8 other compounds, were tentatively characterized with the diagnostic-ion filtering strategy. Based on the diagnostic ions applied to identify compounds in SMW, 28 prototype compounds and 10 metabolic compounds were detected in the biological samples. This was the first comprehensive drug metabolism investigation of SMW in rats. The developed method could be a useful means for identifying the multi-components in SMW and the metabolic components. The results may help explore the possible metabolic processes and mechanism of action for SMW in vivo.

关键词： Si-Miao-Wan LC-Q-TOF/MS Chemical constituents Metabolites

Marine diatom Thalassirosira weissflogii nutrient drawdown and its physiological status variation challenged to zinc and cadmium exposure

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Acta Oceanologica Sinica 2007年第6期26卷 51-61页

作者： li Chundi LONG Aimin YAN wen MA Fujun CHEN Shaoyong Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Key Laboratory of Tropical Marine Environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Graduate School Chinese Academy of Sciences Beijing 100039 China

The uptake of zinc and cadmium by a species of marine diatom Thalassirosira weissflogii and the nutrient variation （ phosphorus and silicon） in the culture medium were estimated when exposed to zinc and cadmium stress under controlled laboratory conditions. It was found that low cadmium addition could stimulate the culture to grow with a relatively high rate and exert its toxicity at the elevated concentration. The cellular uptake of zinc and cadmium by the diatom varied in the ranges of 1.21 - 3.75 and 0. 060 - 0. 629 fmol per cell respectively in the whole cultivation period. The mean cellular phosphorus and silicon drawdowns were constant with 0. 26 - 0. 42 and 0. 30 - 0. 46 pmol per cell respectively in those healthy cultures. It is illustrated that the algal cells can adjust some physiological mechanisms to decrease metal accumulation and keep metal homeostasis in the organism. The correlation analysis results further indicate that the cellular cadmium uptake might be closely related with the cellular phosphorus, silicon drawdown and the growth rate of diatom （P 〈0. 05, 0. 001,0. 01 ） ; and the cultures grow better in good conditions, the lower amount of phosphorus, silicon materials are consumed by a single cell to keep a high efficiency of utilization.

关键词： zinc cadmium diatom replacement phosphate silicate

Equalization for continuous phase modulation over frequency-selective fading channels

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1884-1888页

作者： JIN Xiao-dong ZHAO Min-jian SUN ling SHEN wen-li Department of lnformation Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

This paper presents an equalization algorithm for continuous phase modulation （CPM） over frequency-selective channels. A specific training sequence is first embedded in each data packet. By recursive least-squares （RLS） estimation, the channel information parameters can be acquired, and a fractionally Simulation results show that the proposed algorithm can acquire the spaced equalizer performs joint decoding and equalization. channel information parameters rapidly and accurately, and that the fractionally spaced equalizer can eliminate the intersymbol interference （ISI） effectively, and is not sensitive to timing inaccuracy, so this algorithm can be exploited for demodulation system in burst mode.

关键词： M-ary continuous phase modulation (CPM) Channel-estimation Joint decoding and equalization Fractionally spaced