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201. Extracavity Frequency Doubled Red Laser with Single Frequency

Author

葛青 Ge Qing, 谢常德 Xie Changde, 于琳 Yu Lin, 贾晓军 Jia Xiaojun, 苏晓龙 Su Xiaolong, and 彭堃墀 Peng Kunchi

Subjects
Optics, Materials science, Red laser, business.industry, Electrical and Electronic Engineering, business, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials
Published
2009
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214. Investigation of the CO2Flooding Behavior and Its Collaborative Controlling Factors

Author

Niu, Qinghe, Wang, Wei, Liang, Jingjing, Yuan, Wei, Wen, Lei, Chang, Jiangfang, Ji, Zhongmin, Zhou, He, Wang, Zhenzhi, and Jia, Xiaojun

Abstract

CO2injection to enhance coalbed methane (CO2-ECBM) production is a promising technology for realizing the efficient exploitation of new energy resource, but its effect is cooperatively affected by miscellaneous influencing factors. To elucidate the mechanism and increase the efficiency of the displacement of CH4by CO2, CO2flooding experiments under the influence of the injection pressure, confining pressure, and temperature were conducted. The results show that an increase in the injection pressure enlarges the pore-fracture network of the coal matrix and promotes its gas adsorption ability and seepage capacity, while an increase in the confining pressure compresses the coal body and reduces the adsorption capacity and permeability. Increasing the temperature enhances kinetic energy and induces the thermal swelling effect, which disfavors the adsorption and seepage processes. The CO2adsorption capacity is larger than the CH4adsorption capacity due to the higher adsorption affinity of CO2, but the CO2permeability is lower than the CH4permeability due to the severe adsorption swelling effect. The CO2flooding process is characterized by three parameters (equal percentage displacement time, displacement rate, and displacement efficiency) and can be divided into the CO2driving stage, replacement and displacement stage, and equilibrium stage. The injection pressure and temperature decrease the displacement time and increase the displacement rate and displacement efficiency, while confining pressure shows the opposite trends. Multifactor interaction models of the displacement efficiency of coal seams at various buried depths were established and demonstrated to appropriately predict the displacement efficiency of CO2-ECBM in deep coal seams. The displacement efficiency is controlled by the reservoir performance, geological characteristics, and CO2injection technology. The selection of a high-permeability coal reservoir and coal seams with an appropriate buried depth and the development of a reasonable injection plan are suggested for the implementation of CO2-ECBM extraction.

Published
2020
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227. An index of financial safety of China

Author

Jia, Xiaojun, Li, Menggang, Jia, Xiaojun, and Li, Menggang

Abstract

Purpose: This paper combines a synthetic index system by the variables and evaluates China’s financial safety through the change of indexes in a comprehensive way. First of all, it builds the financial industry evaluation index system composed of 25indicators in terms of the operation of the financial industry and external economic environment and particularly takes into consideration factors which might trigger liquidity risks such as off-balance-sheet business, interbank business and shadow banking; then it selects 10 indicators to conduct empirical analysis and identifies the indicator weight through principal component analysis; finally it combines the financial safety indexes through the linear weighted comprehensive evaluation model. Design/methodology/approach: Synthesis of indexes is made by constructing a proper comprehensive evaluation mathematical model, integrating a number of evaluation indexes into one comprehensive evaluation index and then obtaining corresponding comprehensive evaluation results. In this paper, it selects 10 indexes to conduct empirical analysis and identifies the index weight through principal component analysis; finally it combines the financial safety indexes through the linear weighted comprehensive evaluation model. Principal component analysis (PCA) is a statistical procedure that uses an orthogonal transformation to convert a set of observations of possibly correlated variables into a set of values of linearly uncorrelated variables called principal components. PCA was invented in 1901 and was later independently developed (and named) by Harold Hotelling in the 1930s. Findings: From 2003 to 2013 China’s financial safety indexes fluctuated. From 2003 to 2007 indexes rose, which indicates China’s financial safety status gradually improved; from 2007 to 2009 indexes declined, which indicates due to the impact of subprime crisis, China’s financial safety status took a turn for the worse; from 2009 to 2012 indexes rose, which indic, Peer Reviewed

Published
2015

232. Pure Quantum Correlations Between Bright Optical Beams

Author

Shang, Yana, Yan, Zhihui, Jia, Xiaojun, Su, Xiaolong, Xie, Changde, and Peng, Kunchi

Subjects
Quantum Physics, FOS: Physical sciences, Quantum Physics (quant-ph)
Abstract

The pure quantum correlations totally independent of the classical coherence of light have been experimentally demonstrated. By measuring the visibility of the interference fringes and the correlation variances of amplitude and phase quadratures between a pair of bright twin optical beams with different frequencies produced from a non-degenerate optical parametric oscillator, we found that when classical interference became worse even vanished, the quadrature quantum correlations were not influenced, completely. The presented experiment obviously shows the quantum correlations of light do not necessarily imply the classical coherence.

Published
2008
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233. Experimental investigation to influence of pump phase fluctuation on phase-correlation of output optical fields from a non-degenerate parametric oscillator

Author

Wang, Dong, Shang, Yana, Yan, Zhihui, Wang, Wenzhe, Jia, Xiaojun, Xie, Changde, and Peng, Kunchi

Subjects
Quantum Physics, FOS: Physical sciences, Physics::Optics, Quantum Physics (quant-ph)
Abstract

The influence of the phase fluctuation of the pump laser on the phase-correlation between the signal and idler modes of the output fields from as non-degenerate optical parametric oscillator operating above oscillation threshold was experimentally investigated. The noise spectra of the intensity-difference and the phase-sum of the entangled optical beams were measured with a pair of unbalanced fiber Match-Zehnder interferometers specifically designed. The experimental results proved the previously theoretical prediction and are in reasonable agreement with the calculation based on semiclassical theory involving the phase fluctuation of pump laser., 15 pages

Published
2007

234. Experimental Preparation of Quadripartite Cluster and GHZ Entangled States for Continuous Variables

Author

Su, Xiaolong, Tan, Aihong, Jia*, Xiaojun, Zhang, Jing, Xie, Changde, and Peng, Kunchi

Subjects
Quantum Physics, FOS: Physical sciences, Quantum Physics (quant-ph)
Abstract

The cluster states and Greenberger-Horne-Zeilinger (GHZ) states are two different types of multipartite quantum entangled states. We present the first experimental results generating continuous variable quadripartite cluster and GHZ entangled states of electromagnetic fields. Utilizing four two-mode squeezed states of light and linearly optical transformations, the two types of entangled states for amplitude and phase quadratures of light are experimentally produced. The combinations of the measured quadrature variances prove the full inseparability of the generated four subsystems. The presented experimental schemes show that the multipartite entanglement of continuous variables can be deterministically generated with the relatively simple implementation.

Published
2006
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235. Maternal exposure to fine particulate matter and brain-derived neurotrophic factor (BDNF) in the fetus: A prospective cohort study.

Author

Wang, Cuiping, Jia, Xiaojun, Jin, Hong, Meng, Yu, Ye, Weiping, Zhang, Na, Wang, Weidong, Kan, Haidong, and Zhang, Jun

Subjects
BRAIN-derived neurotrophic factor, MATERNAL exposure, DELIVERY (Obstetrics), PARTICULATE matter, CORD blood, COHORT analysis, LONGITUDINAL method
Abstract

Maternal exposure to ambient fine particulate matter (PM 2.5) during pregnancy has been associated with impaired neurobehavioral development in children. However, the specific mechanism remains unclear. Brain derived neurotrophic factor (BDNF) is an important growth factor in the nervous system. We evaluated the associations of maternal PM 2.5 exposures with fetal BDNF in the umbilical cord blood in a prospective cohort study. A total of 711 eligible mother-infant pairs from the Shanghai Birth Cohort were included in the current study. Daily maternal exposures to ambient PM 2.5 were assessed with a gap-filling approach at 1 * 1 km2 resolution based on self-reported home addresses. The concentrations of BDNF in the cord blood were measured by ELISA. A linear regression model was applied to evaluate the association of maternal ambient PM 2.5 exposure with fetal BDNF level at birth. The median concentration of BDNF was 13,403 pg/ml. Vaginal deliveries and female infants had higher BDNF levels than cesarean deliveries and male infants. One natural log (ln) unit increase in maternal PM 2.5 exposure during the second trimester was significantly associated with − 0.20 (95% CI: −0.36, −0.05) ln-unit decrease in BDNF level in all births. These effects were stronger and more significant in vaginal deliveries and in male infants. Our study suggests that BDNF in the cord blood may serve as a potential biomarker in assessing the neurodevelopmental effects of maternal PM 2.5 exposure. • Limited evidence is available on maternal PM 2.5 exposures and fetal BDNF levels. • Maternal PM 2.5 exposure was negatively associated with fetal BDNF level at birth. • Delivery modes and infant sex may modify the association. [ABSTRACT FROM AUTHOR]

Published
2023
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236. Quantum Key Ditribution Based on Quantum Intensity Correlation of Twin Beams

Author

Jia, Xiaojun, Su, Xiaolong, Pan, Qing, Peng, Kunchi, and Xie, Changde

Subjects
Quantum Physics, FOS: Physical sciences, Quantum Physics (quant-ph)
Abstract

A new and simple quantum key distribution scheme based on the quantum intensity correlation of optical twin beams and the directly local measurements of intensity noise of single optical beam is presented and experimentally demonstrated. Using the twin beams with the quantum intensity correlation of 5dB the effective bit rate of $2\times 10^7bits/s$ is completed. The noncloning of quantum systems and the sensitivity of the existing correlations to losses provide the physical mechamism for the security against eavesdropping. In the presented scheme the signal modulation and homodyne detection are not needed., submitted to journal on March 22,2005

Published
2005

250. Application of a nanotechnology antimicrobial spray to prevent lower urinary tract infection: a multicenter urology trial

Author

He, Wei, primary, Wang, Dongmin, additional, Ye, Zhangqun, additional, Qian, Weihong, additional, Tao, Yan, additional, Shi, Xiaofeng, additional, Liu, Ling, additional, Chen, Jin, additional, Qiu, Ling, additional, Wan, Peng, additional, Jia, Xiaojun, additional, Li, Xia, additional, Gao, Caixia, additional, Ma, Xuexia, additional, Wen, Biyan, additional, Chen, Nianzhen, additional, Li, Ping, additional, Ren, Zhengzheng, additional, Lan, Li, additional, Li, Siyi, additional, Zuo, Yi, additional, Zhang, Hua, additional, Ma, Liming, additional, Zhang, Yueping, additional, Li, Zhicong, additional, Su, Weiping, additional, Yang, Qing, additional, Chen, Qingli, additional, Wang, Xuejing, additional, Ye, Zhenni, additional, Chen, JP, additional, Loo, Wings TY, additional, Chow, Louis WC, additional, Yip, Adrian YS, additional, Ng, Elizabeth LY, additional, Cheung, Mary NB, additional, and Wang, Zhiping, additional

Published
2012
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