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Particle size distribution and characteristics of polycyclic aromatic hydrocarbons during a heavy haze episode in Nanjing,China

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Particuology 2015年第1期13卷 127-134页

作者： Qingzi Meng Shuxian fan Jiabao He Jian Zhang Yu Sun Yue Zhang fan zu Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science and Technology Department of Atmospheric Physics Nanjing University of Information Science and Technology Jiangsu Institute of Meteorological Sciences

A heavy haze episode caused by agricultural burning occurred in Nanjing from November 7 to November 8, 2009. PM10 samples were collected on normal and hazy days from November I to November 14, 2009 at both city and suburban sites of Nanjing. Sixteen PAHs were measured during the day and at night. The results show that the concentrations of the particles were as high as 579.55 and 573.43 μg/m^3 during the haze episode at the city and suburban sites, respectively, 3-4 times higher than those on a normal day. The proportions of fine particles during the haze episode were also higher than those on a normal day. The changes in the concentrations of PAHs were in accordance with the concentrations of the particles. High- molecular-weight PAHs composed approximately 80% of the total PAHs on normal days and during the haze episode. The concentration of PAHs in fine fractions significantly increased during the haze episode, and this increase was most obvious at night at the city site, The proportion of total carcinogenic PAHs in fine particles was relatively high during the haze episode at both sampling sites, particularly at night at the city site.

关键词： Polycyclic aromatic hydrocarbons Agricultural burning Haze episode Particle size distribution Meteorological conditions Nanjing

Analytical general results for handoff dwell time distribution in wireless networks

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 29-33页

作者： ZHANG zu-fan DU Hui-ping JIANG Ze University of Posts and Telecommunications Chongqing 400065 China University of Electronic Science and Technology of China Chengdu 610065 China

This article presents a general evaluation of handoff dwell time distribution based on geometric analysis methods. Considering the geometric characteristic of the deployed sector pattern, and the distribution of the users＇ position and the moving direction in the given sector, the general formulas of the probability density function of sector handoff dwell time are derived. Some numerical results are also presented for illustration.

关键词： wireless networks handoff dwell time probability density function

High isolation dual-element modified PIFA array for MIMO application

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The Journal of China Universities of Posts and Telecommunications 2012年第3期19卷 1-6页

作者： LOU Si-yan LI Xiao-lin ZHANG zu-fan School of Communication and Information Engineering Chongqing University of Posts and Telecommunications Chongqing 400065 China Chongqing Information Technology Designing CO. LTD. Chongqing 400065 China

In this paper, we focus on antenna array design for mobile phone with finite volume and propose a novel antenna element structure by capacitive feeding and capacitive loading method based on the planar inverted F antenna （PIFA）. State-of-the-art development on this issue is reviewed. Then, a novel capacitively fed and capacitively loaded PIFA structure is proposed and studied. The results of the experiments showed that our structure can reduce the coupling of antenna elements from - 13.4 dB to -24.5 dB. Finally, a design with a bandwidth of 100 MHz centered at 2.35 GHz and envelopment correlation coefficient of 0.01 2 is provided and the diversity performance of the dual-element modified PIFA array is evaluated in both simulation and measurement. In a word, our novel design reaches broadband, miniaturization, high isolation and offers excellent diversity performance.

关键词： MIMO PIFA isolation capacitive feed capacitive load

Residual energy based multi-relay selection and power allocation scheme in two-way relay network

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The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 39-45页

作者： DAI Cui-qin LI Fu-jia ZHANG zu-fan Chongqing Key Lab of Mobile Communication Technology Chongqing University of Posts and Telecommunications

In this paper, we have proposed a multi-relay selection and power allocation scheme for two-way relay network which aims to maximize the sum-rate of two-way relay system. First, to prolong network lifetime, a multi-relay selection strategy is proposed in which both channel state information （CSI） and remaining energy （RE） are considered. Next, a multi-relay power allocation algorithm based on convex optimization （MRPA-CO） is presented. To reduce the computational complexity, it can be divided into two steps： terminal nodes power allocation （TNPA） and relay nodes power allocation （RNPA）. Simulation results indicate that the proposed relay selection strategy can significantly prolong network lifetime compared to other relay selection strategies which consider CSI only, and the MRPA-CO algorithm has great advantage over equal power allocation （EPA） on sum-rate in two-way relay network.

关键词： two-way relay remaining energy multi-relay selection power allocation sum-rate

Joint power allocation and subcarrier pairing in OFDM-based cooperative relaying system

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The Journal of China Universities of Posts and Telecommunications 2012年第1期19卷 24-30页

作者： DAI Cui-qin ZHAO Xiao-yu ZHANG zu-fan Chongqing Key Lab of Mobile Communication Technology Chongqing University of Posts and TelecommunicationsChongqing 400065China

This paper proposes rate-maximized （MR） joint subcarrier pairing （SP） and power allocation （PA）（MR-SP＆PA）, a novel scheme for maximizing the weighted sum rate of the orthogonal-frequency-division multiplexing （OFDM） relaying system with a decode-and-forward （DF） relay. MR-SP＆PA is based on the joint optimization of both SP and power allocation with total power constraint, and formulated as a mixed integer programming problem in the paper. The programming problem is then transformed to a convex optimization problem by using continuous relaxation, and solved in the Lagrangian dual domain. Simulation results show that MR-SP＆PA can maximize the weighted sum rate under total power constraint and outperform equal power allocation （EPA） and proportion power allocation （PCG）.

关键词： OFDM DF relaying power allocation SP MR-SP&PA

Interference-Limited Device-to-Device Multi-User Cooperation Scheme for Optimization of Edge Networking

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Journal of Computer Science & Technology 2016年第6期31卷 1096-1109页

作者： Hong-Cheng Huang Jie Zhang zu-fan Zhang Zhong-Yang Xiong College of Computer Science Chongqing University Chongqing 400044 China School of Communication and Information Engineering Chongqing University of Posts and Telecommunications Chongqing 400065 China

Device-to-device （D2D） communication is an emerging technology for improving cellular networks, which plays an important role in realizing Internet of Things （IoT）. The spectrum efficiency, energy efficiency and throughput of network can be enhanced by the cooperation among multiple D2D users in a self-organized method. In order to limit the interference of D2D users and load off the energy consumption of D2D users without decreasing communication quality, an interference- limited multi-user cooperation scheme is proposed for multiple D2D users to solve the energy problem and the interference problem in this paper. Multiple D2D users use non-orthogonal spectrums to form clusters by self-organized method. Multiple D2D users are divided into different cooperative units. There is no interference among different cooperative units so as to limit the interference of each D2D user in cooperative units. When the link capacity cannot meet the requirements of the user rate, it will produce an interrupt event. In order to evaluate the communication quality, the outrage probability of D2D link is derived by considering link delay threshold, data rate and interference. Besides the energy availability and signal-to-noise ratio （SNR） of each D2D user, the distance between D2D users is considered when selecting the relaying D2D users so as to enhance the signal-to-interference-plus-noise ratio （SINR） of D2D receiving users. Combining the derived outrage probability, the relationships among the average link delay threshold, the efficiency of energy and the efficiency of capacity are studied. The simulation results show that the interference-limited multiple D2D users cooperation scheme can not only help to offioad energy consumption and limit the interference of D2D users, but also enhance the efficiency of energy and the efficiency of capacity.

关键词： device-to-device (D2D) user cooperation relay selection efficiency of energy efficiency of capacity Internetof Things (IoT)

Inhibitory effect of norcantharidin on the growth of human gallbladder carcinoma GBC-SD cells in vitro

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Hepatobiliary & Pancreatic Diseases International 2007年第1期6卷 72-80页

作者： fan, Yue-zu Fu, Jin-Ye Zhao, Ze-Ming Chen, Chun-Qiu Tongji Univ Tongji Hosp Dept Gen Surg Shanghai 200065 Peoples R China Pudong Peoples Hosp Dept Surg Shanghai 201200 Peoples R China

BACKGROUND: Gallbladder carcinoma is a lethal malignant neoplasm with dismal surgical results. Unfortunately, the adjuvant therapies for gallbladder carcinoma such as chemotherapy and radiotherapy are also disappointing. We reported that norcantharidin (NCTD), a demethylated form of cantharidin, which is an active ingredient of the Chinese medicine Mylabris, was used against human gallbladder carcinoma GBC-SD cells. In the present study, we further studied the mechanism underlying the inhibitory effect of NCTD on growth of human gallbladder carcinoma GBC-SD cells in vitro. METHODS: Human gallbladder carcinoma GBC-SD cells were grown in cell culture and divided into a NCTD group and a control group. The inhibitory effect of NCTD on growth of GBC-SD cells was investigated by evaluation of proliferation, cell cycle, apoptosis and morphological changes of the cells. Cell proliferation was assessed by tetrazolium-based colorimetric assay. The induction of cell cycle arrest and apoptosis was measured by flow cytometry. The morphological changes of the cells were observed by light- and electron-microscopy. To elucidate the anticancer mechanism of NCTD, expression of the proliferation-related gene proteins PCNA, Ki-67, cyclin-D-1 and p27 and the apoptosis-related gene proteins Bcl-2, Bax and Survivin were determined by the streptavidin-biotin complex method and RT-PCR. RESULTS: NCTD inhibited the proliferation of GBCSD cells in a dose- and time-dependent manner, with an IC50 of 56.18 mu g/ml at 48 hours. The flow cytometric profiles revealed that NCTD (at the IC50 for 48 hours) significantly increased the proportion of cells in G(2)/M phase and significantly decreased the proportion of cells in S phase, with a significantly increased rate of cell apoptosis. After treatment with the 48-hour IC50 dose of NCTD, cell shrinkage, vacuolar cytoplasm, membrane budding, karyorrhexis, karyolysis, chromosome condensation and chromatin aggregation in some GBCSD cells were observed by l

关键词： norcantharidin gallbladder neoplasm growth proliferation cell cycle apoptosis proliferation- and apoptosis-related genes

Influence of sea-land breeze on the formation and dissipation of severe dense fog and its burst reinforcement in the Yellow Sea coastal area,China

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Science China Earth Sciences 2024年第2期67卷 432-449页

作者： Ya GAO Duanyang LIU Shuqi YAN Wenjun ZHOU Hongbin WANG fan zu Qin MEI Chuanxiang YI Ye SHENG Key Laboratory of Transportation Meteorology of China Meteorological Administration Nanjing210041China Yancheng Meteorological Bureau Yancheng224000China Nanjing Joint Institute for Atmospheric Sciences Nanjing210041China Key Laboratory of Disaster Weather Chinese Academy of Meteorological SciencesBeijing100086China

Based on the global reanalysis data of the National Centers for Environmental Prediction(NCEP)/National Center for Atmospheric Research,the surface meteorological observation data,sounding data and satellite observation data,this paper comprehensively analyzes the evolution process and formation mechanism of a persistent severe dense fog process occurred on February 15–17,2015 in Yancheng,eastern *** the numerical simulation experiment of Weather Research and Forecast(WRF)model,we further analyze the impact of sea-land breeze on the formation and burst reinforcement of *** show that the precipitation caused by the southwesterly airflow in front of the upper-level trough and the low-pressure inverted trough are conducive to the formation of early rain fog,while the nighttime clear radiance under the control of surface cold high and the infiltration of weak cold advection are conducive to the formation and development of later radiation-advection *** WRF model simulates the fog evolution process,which is basically consistent with the actual fog area,and the simulation results are credible to a certain *** simulation results show that the establishment of sea breeze has an advection cooling effect on the near surface layer,which is conducive to the formation and development of the inversion layer on the near surface,providing stable stratification conditions for the formation and burst reinforcement of *** one hand,the strengthening of sea breeze circulation can continuously transport water vapor to the study *** the other,the occurrence of ultra-low level jet is favorable for the accumulation of low-level water *** the same time,the inversion intensity further strengthens,which is in favor of the burst reinforcement and long-term maintenance of fog.

关键词： Radiation-advection fog Sea-land breeze Atmospheric boundary layer Fog burst reinforcement WRF model

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Norcantharidin inhibits growth of human gallbladder carcinoma xenografted tumors in nude mice by inducing apoptosis and blocking the cell cycle in vivo

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Hepatobiliary & Pancreatic Diseases International 2010年第4期9卷 414-422页

作者： fan, Yue-zu Zhao, Ze-Ming Fu, Jin-Ye Chen, Chun-Qiu Sun, Wei Tongji Univ Sch Med Tongji Hosp Dept Surg Shanghai 200065 Peoples R China Shanghai Jiao Tong Univ Peoples Hosp 9 Dept Surg Shanghai 200065 Peoples R China

BACKGROUND: Gallbladder carcinoma, a lethal malignant neoplasm with poor prognosis, has dismal results of surgical resection and chemoradiotherapy. We previously reported that norcantharidin (NCTD) is useful against growth, proliferation, and invasion of human gallbladder carcinoma GBC-SD cells in vitro. In this study, we further studied the inhibitory effect of NCTD on the growth of xenografted tumors of human gallbladder carcinoma in nude mice in vivo and the underlying mechanisms. METHODS: The tumor xenograft model of human gallbladder carcinoma in nude mice in vivo was established with subcutaneous GBC-SD cells. The experimental mice were randomly divided into control, 5-FU, NCTD, and NCTD+5-FU groups which were given different treatments. Tumor growth in terms of size, growth curve, and inhibitory rate was evaluated. Cell cycle, apoptosis, and morphological changes of the xenografted tumors were assessed by flow cytometry and light/electron microscopy. The expression of the cell cycle-related proteins cyclin-D1 and p27 as well as the apoptosis-related proteins Bcl-2, Box, and survivin were determined by the streptavidin-biotin complex (SABC) method and RT-PCR. RESULTS: NCTD inhibited the growth of the xenografted tumors in a dose- and time-dependent manner. Tumor volume decreased (5.61+/-0.39 vs. 9.78+/-0.61 cm(3), P=0.000) with an increased tumor inhibitory rate (42.63% vs. 0%, P=0.012) in the NTCD group compared with the control group. The apoptosis rate increased (15.08+/-1.49% vs. 5.49+/-0.59%, P=0.0001) along with a decreased percentage of cells in S phase (43.47+/-2.83% vs. 69.85+/-1.96%, P=0.0001) in the NTCD group compared with the control group. The morphological changes of apoptosis such as nuclear shrinkage, chromatin aggregation, chromosome condensation, and typical apoptosis bodies in the xenografted tumor cells induced by NCTD were observed by light and electron microscopy. The expression of cyclin-D1, Bcl-2 and survivin proteins/mRNAs decreased s

关键词： norcantharidin gallbladder neoplasm tumor growth apoptosis cell cycle