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Characteristics of air pollution by polychlorinated dibenzo-p-dioxins and dibenzofurans in the typical industrial areas of Tangshan City,China

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Journal of Environmental Sciences 2011年第2期23卷 228-235页

作者： Zhiyuan Ren Bing Zhang pu Lu cheng Li Lirong Gao Minghui Zheng Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

The ambient air in vicinity of different industrial sources for PCDD/PCDFs was sampled by TSP/PM10 active samplers and passive puF disk samplers in Tangshan City, a metropolis containing clusters of various industrial plants. The TEQ concentrations of PCDD/PCDFs ranged from 44.2 to 394.1 fg I-TEQ/m^3 with an average of 169.9 fg I-TEQ]m^3. 2,3,4,7,8-PeCDF was the dominant contributor to ∑TEQ, contributing 41% （12% to 55%）, while 1,2,3,4,6,7,8-HpCDE OCDD and OCDF were the major congeners for the total concentrations. The ratios of ∑PCDF/∑PCDD reached 2.54 on average, suggesting that de novo synthesis in thermal processes played an important role to the airborne pollution of PCDD/PCDFs. The similarities congener profiles indicated that TSP and PM10 active sampling methods are comparable for the determination of the PCDD/PCDFs in ambient air, and the ratios of concentrations determined by the two methods suggested that the PCDD/PCDFs tended to stay in fine particles. It was found that 2,3,7,8-TCDF and OCDD were the dominating congeners in the passive puF disks samples. Through principal components analysis, the coke industry was suggested to be a relatively high potential emission source for PCDD/PCDFs in the ambient air of Tangshan, which was possibly formed by de novo synthesis mechanism. In this study, the atmospheric impacts to the environment from different industrial sources could be ranked as follows （from high to low）： coking, iron sintering, steel making, power generation and chlorinate alkali chemical production industries.

关键词： ambient air dioxins inhalable particles total suspended particles metropolis

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Research on Multi-robot Coordination Searching Ignition Sources Approach

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 50-54页

作者： Jun Li Wen-Long Song pu-cheng Zhou College Mechanical and Electrical Northeast Forestry University Dept. of Information Engineering Artillery Academy of PLA

For the purpose of study on forecasting forest fire behavior,a probability approach was presented to search ignition sources by multi-robot coordination. Firstly,the environment map is built based on Bayes rules. Then,the probability searching strategy based on the environment map was designed. Every grid of the searching area was assigned searching expectation value, and robots selected the grid with the highest expectation value as its searching target. The simulation results show the search time reduces greatly,which proves the feasibility and validity of the given algorithm under unknown fire condition.

关键词： fire-fighting robots Bayes rules multi-robot coordination

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Separation of lithium and nickel using ionic liquids and tributyl phosphate

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Chinese Journal of Chemical Engineering 2023年第11期63卷 63-70页

作者： Kun Wang Guoquan Zhang Linye Li Yuzhang Li Xiangxin Liao pu cheng Mingzhi Luo School of Chemical Engineering Sichuan UniversityChengdu 610065China

With the vigorous development of the electronics industry,the consumption of lithium continues to increase,and more lithium needs to be mined to meet the development of the *** content of lithium in the solution is much higher than that of minerals,but the interference of impurity ions increases the difficulty of extracting lithium ***,we prepared an imidazole-based ionic liquid(1-butyl-3-methylImidazolium bis(trifluoromethyl sulfonyl)imide)(IL)for efficient lithium extraction from aqueous solutions by solvent *** an extraction consisting of 10%IL,85% tributyl phosphate(TBP),and 5% dichloroethane and an organic to aqueous phase ratio(O/A)of 2/1,over 64.23% of Li were extracted,and the extraction rate after five-stage extraction could reach more than 96%.The addition of ammonium ions to the solution inhibited the extraction of Ni,and the separation coefficient between lithium and nickel approached infinity,showing a very perfect separation *** infrared spectroscopy and slope methods were used to analyze the changes that occurred during extraction,revealing possible extraction *** addition,the LiCl solution generated during the preparation of ionic liquids was mixed with the stripping solution,and the battery-grade lithium carbonate was prepared by Na_(2)CO_(3) precipitation,with a purity of 99.74%.This study provides an efficient and sustainable strategy for recovering lithium from the solution.

关键词： Ionic liquids Selective separation Solvent extraction Lithium

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Long-term outcomes in patients with ypT0 rectal cancer after neoadjuvant chemoradiotherapy and curative resection

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Chinese Journal of Cancer Research 2018年第2期30卷 272-281页

作者： Zhao Lu pu cheng Fu Yang Zhaoxu Zheng Xishan Wang Department of Colorectal Surgery National Cancer Center/Cancer Hospital Chinese Academy of Medical Sciences and Peking Union Medical College

Objective： For patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy（NCRT）, significant pathological response of the primary tumor has been proposed to identify candidates for organ preservation. However, this does not address metastatic lymph nodes in the mesorectum. The aim of this study was to assess the incidence of lymph node metastases in ypT0 patients treated with NCRT and curative resection and to explore risk factors associated with ***： This was a retrospective study of patients with ypT0 rectal cancer after NCRT and curative resection at a tertiary care center in China from 2005 to ***： A total of 60（18.6%） patients who underwent surgery after NCRT and achieved ypT0 were enrolled in this study; one patient was excluded owing to lack of follow-up. Of these 59 patients, lymph node metastases were found in the mesorectum（ypT0N＋） in eight（13.6%） patients. After a median follow-up of 52 months, 5-year recurrence-free survival（82.7% vs. 62.5%, P=0.014） and overall survival（OS）（90.9% vs. 70.0%, P=0.032） were much higher in ypN0 than yp N＋ patients. Multivariate analyses showed that ypN＋ status（P=0.009） and perioperative blood transfusion（BT）（P=0.001） were significantly independent risk factors associated with recurrence; however, no factor was correlated with 5-year ***： Patients with ypT0N0 rectal cancer can achieve excellent long-term outcomes; however, positive lymph nodes or tumor deposits can still be found in 13.6% of ypT0 patients. Nodal positivity in the mesorectum and perioperative BT are independent risk factors for recurrence.

关键词： Rectal cancer neoadjuvant chemoradiotherapy pathological response lymph node risk factor

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Deep-cryogenic-treatment-induced phase transformation in the Al-Zn-Mg-Cu alloy

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International Journal of Minerals,Metallurgy and Materials 2015年第1期22卷 68-77页

作者： Chun-mei Li Nan-pu cheng Zhi-qian Chen Ning Guo Su-min Zeng School of Materials Science and Engineering Central South University School of Materials Science and Engineering Southwest University

An aluminum alloy （Al-Zn-Mg-Cu） subjected to deep cryogenic treatment （DCT） was systematically investigated. The results show that a DCT-induced phase transformation varies the microstructures and affects the mechanical properties of the Al alloy. Both Guinier-Preston （GP） zones and a metastableη′phase were observed by high-resolution transmission electron microscopy. The phenomenon of the second precipitation of the GP zones in samples subjected to DCT after being aged was observed. The viability of this phase transfor-mation was also demonstrated by first-principles calculations.

关键词： aluminum alloys cryogenic treatment phase transformation microstructure

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Remote Sensing Data Processing Process Scheduling Based on Reinforcement Learning in Cloud Environment

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 1965-1979页

作者： Ying Du Shuo Zhang pu cheng Rita Yi Man Li Xiao-Guang Yue School of Computer and Information Engineering Henan UniversityKaifeng475004China Henan Province Engineering Research Center of Spatial Information Processing Henan UniversityKaifeng475004China School of Software Henan UniversityKaifeng475004China Department of Economics and Finance/Sustainable Real Estate Research Center Hong Kong Shue Yan UniversityHong Kong999077China Department of Computer Science and Engineering European University CyprusNicosia1516Cyprus CIICESI-ESTG Politécnico do PortoFelgueiras4610-156Portugal

Task scheduling plays a crucial role in cloud computing and is a key factor determining cloud computing *** solve the task scheduling problem for remote sensing data processing in cloud computing,this paper proposes a workflow task scheduling algorithm—Workflow Task Scheduling Algorithm based on Deep Reinforcement Learning(WDRL).The remote sensing data process modeling is transformed into a directed acyclic graph scheduling ***,the algorithm is designed by establishing a Markov decision model and adopting a fitness calculation ***,combine the advantages of reinforcement learning and deep neural networks to minimize make-time for remote sensing data processes from *** experiment is based on the development of CloudSim and Python and compares the change of completion time in the process of remote sensing *** results showthat compared with several traditionalmeta-heuristic scheduling algorithms,WDRL can effectively achieve the goal of optimizing task scheduling efficiency.

关键词： Cloud computing reinforcement learning remote sensing task scheduling

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New Thymol Derivate from Centipeda minima

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Chemical Research in Chinese Universities 2009年第1期25卷 125-126页

作者： pu Shou-cheng GUO Yuan-qiang GAO Wen-yuan ZHANG Tie-jun School of Pharmaceutical Science and Technology Tianjin University Tianjin 300072 P. R. China Department of Pharmaceutical Sciences Nankai University Tianjin 300071 P. R. China Tianjin Institute of Pharmaceutical Research Tianjin 300193 P. R. China

1 Introduction Centipeda minima（Compositae） is an annual herbaceous plant found in moist places throughout the plains mainly in the southern regions of the People＇s Republic of China, Eastern tropical Asia, Australia and the Pacific Islands. It is a commonly used Chinese folk medicine for colds, whooping cough, nasal allergy, malaria and asthma. A number of sesquiterpene lactones, flavonoids and triterpenes have previously been isolated from C. minima. During our study on searching for biological active components from this plant,

关键词： Centipeda minima Thymol derivate Thymohydroquinone 6-O-β-6'-acetyl-Glc

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Synergistic Effects of Gamma Irradiation,Tensile Stress and Moisture on the Radiolysis of Silicone Foam

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Chinese Journal of Polymer Science 2023年第12期41卷 1969-1978,I0011页

作者： pu-cheng Wang Qiang Liu Bo Liu Wei Huang You An Jian-Yong Liu Hong-Bing Chen Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621000China

The present work involves the investigation of the synergistic effects of gamma irradiation,tensile stress and absorbed moisture on the radiolysis behaviors of silicone foams by experiments and theoretical *** both the pristine and dehydrated samples,the permanent tensile set increases with the initial tensile *** analysis uncovers that the dehydrated samples exhibit greater permanent tensile sets,lower further elongation and higher Young’s modulus than the counterparts of the pristine samples with the same initial tensile strain and gamma dose,verifying the vital synergistic effects on crosslinking network and aggregation structures caused by moisture and gamma *** synergistic effects unveiled by reactive molecular dynamics at the atomic scale are due to the moisture-induced neutralization and stabilization of the macromolecular *** steric hindrance of moisture located at the interface of silica and polymer chains also conduces to the observed synergistic effects due to the inhibited crosslinking reactions.

关键词： Silicone foam Synergistic effect Gamma irradiation Tensile stress Moisture

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INTERDECADAL VARIABILITY OF QUASI-BIENNIAL OSCILLATION OF STRATOSPHERIC ZONAL WIND

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Journal of Tropical Meteorology 2019年第2期25卷 162-170页

作者： HAN pu-cheng JIAN Mao-qiu LIN Xiao-xia School of Atmospheric Sciences/Center for Monsoon and Environment Research/Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen University Guangdong Meteorological Observatory Guangdong Meteorological Observation Data Center

This study investigates the interdecadal variability of Quasi-biennial Oscillation(QBO) based on the sounding data in the stratosphere, ERA-40 and ERA-interim reanalysis data in the past 62 years. The QBO periodicity experiences a significant interdecadal variability; the longer(shorter) the mean period, the smaller(larger) the amplitude of variation is. The QBO amplitude varies in a cycle around 10 to 15 years and in an out-of-phase correlation with the period. In addition, there is an increasing trend of the QBO amplitude in 30 to 10 hPa, while a little declining trend in70 to 40 hPa. The deviation of the QBO zonal wind extremum centers from the equator also shows interdecadal variability. The deviation location of the easterly core is generally in the reverse side to the westerly core, which means that when the easterly core is on one side of a hemisphere, the westerly core is on the other side.

关键词： statistical feature QBO interdecadal variability zonal wind asymmetric feature

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Parameter self-adaptive synchronization control for a kind of financial chaotic systems

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重庆邮电大学学报（自然科学版） 2009年第2期21卷 217-221页

作者： pu Xing-cheng WANG Hai-ying Department of Mathematics and Physics Chongqing University of Posts and Telecommunications Chongqing 400065 P. R. China Chongqing University of Posts and Telecommunications Chongqing 400065 P. R. China

A parameter adaptive control approach was applied to a kind of financial chaotic *** to Lyapunov stability theorem,synchronization of two financial chaotic systems with different certain parameters or the same uncertain parameters were implemented through designing proper control functions and using parameters self-adaptive control *** sufficient synchronization conditions of the two financial systems were *** the situation of the same uncertain parameters,the synchronization system has simpler controller and better *** simulations show the effectiveness of the method.

关键词：自适应同步控制混沌系统金融体系 Lyapunov稳定性定理参数自适应控制不确定参数控制功能充分条件

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