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Hadronic Transport Effects on Elliptic Flow

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Chinese Physics Letters 2011年第12期28卷 100-103页

作者： LI Na SHI shu-su Department of Physics Huazhong University of Science and TechnologyWuhan 430074 Institute of Particle Physics Central China Normal UniversityWuhan 430079 The Key Laboratory of Quark and Lepton Physics(Ministry of Education) Cental China Normal UniversityWuhan 430079

Elliptic flow v2 is considered as a probe to study partonic collectivity,and the measurement v2/εcan be used to describe the hydro behavior of the colliding *** study the the effect of the hadronic process on the momentum anisotropy parameter v2 in a multiphase transport *** is found that hadronic rescattering will depress the v2 signal built up at the partonic phase.A similar mass hierarchy is observed in the model as in the experiment at *** find that different particle species will approach the same ideal hydro limit if the hadronic process is excluded.

关键词： Elliptic hadron momentum

Polarization of ∧'s Produced in S+Pb Collisions at 200 GeV/c per Nucleon

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Chinese Physics Letters 1996年第5期13卷 351-354页

作者： YE Yun-xiu su shu-fang JI Gang Department of Modern Physics University of Science arid Technology of ChinaHefei 230027 Department of Special Class for Gifted Young University of Science arid Technology of ChinaHefei 230027

The ∧^(0) polarization is analyzed with the experinental data in S+Pb collisions at energy 200GeV per nucleon,which were produced at SPS of *** *** rxalue and thecorrelation betrween the transverse polarization and transverse momentum were obtained in Feyn-man parameter x_(F)>0,r_(F)sults show that the non-polarization of lamb-da appears in the vegion of larger transterse momenta,say,at 1-2 GeV/c in P_(T).The originsof polarization reduction are discussed.

关键词： GeV/c transverse Polarization

Exchange Rate Pass-through in China

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China & World Economy 2009年第1期17卷 33-46页

作者： Chang shu Xiaojing su Hong Kong Monetary Authority Hong Kong

During the second half of 2007 and early part of 2008 when there were intense inflationary pressures in China, RMB appreciation was advocated as a means of helping to curb inflation. The effectiveness of appreciation in controlling inflation depends on the impact of exchange rate movements on import and domestic prices. Our analysis finds fairly large and speedy exchange rate pass-through （ERPT） to import prices： 50 and 60percent for the short run and long run, respectively. However, the degree of ERPT decreases along the price chain from upstream to downstream prices. ERPT for consumer prices, the most downstream prices, is much milder and has substantial lags. A 10-percent rise in the nominal effective exchange rate will dampen consumer prices by 1.1 percent within a year, with very little pass-through in the first half year, and by 2.0percent over the long run. These findings, particularly the ERPT to consumer prices, suggest that RMB appreciation can help to reduce inflationary pressures over the longer term. However, it is unlikely to provide rapid relief to the current round of high inflation because of the long lags in ERPZ. The RMB needs to strengthen in effective terms to exert the desired dampening impact on prices.

关键词： exchange rate pass-through import prices inflation RMB appreciation

Spatial-temporal variations in net primary productivity in the Arctic from 2003 to 2016

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Acta Oceanologica Sinica 2019年第8期38卷 111-121页

作者： Haili Li Changqing Ke Qinghui Zhu su shu Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Nanjing University Nanjing 210023 China School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210023 China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210023 China Navigation College Dalian Maritime University Dalian 116026 China

The area of Arctic sea ice has dramatically decreased, and the length of the open water season has increased;these patterns have been observed by satellite remote sensing since the 1970 s. In this paper, we calculate the net primary productivity(NPP, calculated by carbon) from 2003 to 2016 based on sea ice concentration products,chlorophyll a(Chl a) concentration, photosynthetically active radiation(PAR), sea surface temperature(SST), and sunshine duration data. We then analyse the spatiotemporal changes in the Chl a concentration and NPP and further investigate the relations among NPP, the open water area, and the length of the open water season. The results indicate that(1) the Chl a concentration increased by 0.025 mg/m^3 per year;(2) the NPP increased by 4.29 mg/(m^2·d) per year, reaching a maximum of 525.74 mg/(m^2·d) in 2016;and(3) the Arctic open water area increased by 57.23×10^3 km^2/a, with a growth rate of 1.53 d/a for the length of the open water season. The annual NPP was significantly positively related to the open water area, the length of the open water season and the *** daily NPP was also found to have a lag correlation with the open water area, with a lag time of two *** global warming, NPP has maintained an increasing trend, with the most significant increase occurring in the Kara Sea. In summary, this study provides a macroscopic understanding of the distribution of phytoplankton in the Arctic, which is valuable information for the evaluation and management of marine ecological environments.

关键词： sea ice open water area chlorophyll a net primary productivity Arctic

Parameter optimization model in electrical discharge machining process

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 104-108页

作者： Qing GAO Qin-he ZHANG shu-peng su Jian-hua ZHANG School of Mechanical Engineering Shandong University Jinan 250061 China

Electrical discharge machining (EDM) process, at present is still an experience process, wherein selected parameters are often far from the optimum, and at the same time selecting optimization parameters is costly and time consuming. In this paper, artificial neural network (ANN) and genetic algorithm (GA) are used together to establish the parameter optimization model. An ANN model which adapts Levenberg-Marquardt algorithm has been set up to represent the relationship between material removal rate (MRR) and input parameters, and GA is used to optimize parameters, so that optimization results are obtained. The model is shown to be effective, and MRR is improved using optimized machining parameters.

关键词： Electrical discharge machining (EDM) Genetic algorithm (GA) Artificial neural network (ANN) Levenberg- Marquardt algorithm

Human bronchial epithelial cell injuries induced by fine particulate matter from sandstorm and non-sandstorm periods：Association with particle constituents

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Journal of Environmental Sciences 2016年第9期28卷 201-210页

作者： Bin Wang Ning Li Furong Deng Nicholas Buglak George Park shu su Aiguo Ren Guofeng Shen shu Tao Xinbiao Guo Institute of Reproductive & Child Health/Ministry of Health Key Laboratory of Reproductive Health School of Public Health Peking University Beijing 100192 China Department of Pathobiology & Diagnostic Investigation College of Veterinary Medicine Michigan State University East Lansing 48824 USA Department of Occupational & Environmental Health Sciences School of Public Health Peking University Beijing 100191 China Laboratory for Earth surface Processes College of Urban & Environmental Sciences Peking University Beijing 100871 China Jiangsu Provincial Academy of Environmental Science Nanjing 210036 China

Epidemiological studies have demonstrated the exacerbation of respiratory diseases following sandstorm-derived particulate matter（PM） *** presence of anthropogenic and biological agents on the sandstorm PM and the escalation of PM 〈 2.5 μm（PM2.5）pollution in China have led to serious concerns regarding the health effects of PM2.5during Asian *** investigated how changes in PM2.5composition,as the weather transitioned towards a sandstorm,affected human airway epithelial *** PM2.5samples covering two sandstorm events and their respective background and transition periods were collected in Baotou,an industrial city near the Gobi Desert in *** samples from all three periods had mild cytotoxicity in human bronchial epithelial cell line BEAS-2B,which was positively correlated with the contents of polycyclic aromatic hydrocarbons and several *** PM samples potently increased the release of interleukin-6（IL-6） and interleukin-8（IL-8）.Endotoxin in all samples contributed significantly to the IL-6 response,with only a minor effect on *** was positively correlated with both IL-6 and IL-8 release,while Si was only associated with the increase of *** study suggests that local agricultural and industrial surroundings in addition to the sandstorm play important roles in the respiratory effects of sandstorm-derived PM.

关键词： Sandstorm particles Human bronchial epithelial cells Particle constituents Inflammation Local environmental surroundings

Event plane determination from the zero degree calorimeter at the cooling storage ring external-target experiment

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Nuclear Science and Techniques 2023年第7期34卷 113-121页

作者： Li-Ke Liu Hua Pei Ya-Ping Wang Biao Zhang Nu Xu shu-su Shi Key Laboratory of Quark and Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China

The Cooling Storage Ring external-target experiment(CEE)spectrometer is used to study the nuclear matter created in heavy-ion collisions at√sNN=2.1-2.4 GeV with the aim to reveal the quantum chromodynamics phase structure in the high-baryon-density *** flow is considered an effective probe for evaluating the properties of media during high-energy nuclear *** of the main functions of the zero-degree calorimeter(ZDC),a subdetector system in the CEE,is to determine the reaction plane in heavy-ion *** step is crucial for measuring the collective flow and other reaction-plane-related *** this paper,we illustrate the procedures for event plane determination using the ***,isospin-dependent quantum molecular dynamics model-based predictions of the rapidity dependence of the directed and elliptical flows for p,d,t,3He,and 4He,produced in 2.1 GeV U+U collisions,are presented.

关键词： QCD phase structure Heavy-ion collisions Collective flow Reaction plane Zero-degree calorimeter

Classifier for centrality determination with zero-degree calorimeter at the cooling-storage-ring external-target experiment

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Nuclear Science and Techniques 2023年第11期34卷 168-173页

作者： Biao Zhang Li‑Ke Liu Hua Pei shu‑su Shi Nu Xu Ya‑Ping Wang Key Laboratory of Quark and Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China

The zero-degree calorimeter(ZDC)plays a crucial role toward determining the centrality in the Cooling-Storage-Ring External-target Experiment(CEE)at the Heavy Ion Research Facility in Lanzhou.A boosted decision tree(BDT)multi-classification algorithm was employed to classify the centrality of the collision events based on the raw features from ZDC such as the number of fired channels and deposited *** data from simulated^(238)U+^(238)U collisions at 500 MeV∕u,generated by the IQMD event generator and subsequently modeled using the GEANT4 package,were employed to train and test the BDT *** results showed the high accuracy of the multi-classification model adopted in ZDC for centrality determination,which is robust against variations in different factors of detector geometry and *** study demon-strates the good performance of CEE-ZDC in determining the centrality in nucleus-nucleus collisions.

关键词： ZDC Boosted decision trees Multi-classification IQMD Centrality determination

Grafting Increases the Copper Tolerance of Cucumber Seedlings by Improvement of Polyamine Contents and Enhancement of Antioxidant Enzymes Activity

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Agricultural Sciences in China 2010年第7期9卷 985-994页

作者： ZHANG Zi-kun LIU Shi-qi HAO shu-qin LIU su-hui State Key Laboratory of Crop Biology/Key Laboratory of Horticultural Crop Biology College of Horticulture Science and Engineering Shandong Agricultural University Tai＇an 271018 P.R. China

The aim of the study is to determine whether grafting could improve antioxidant enzyme activities and polyamine contents in leaves of cucumber plants（Cucumis sativus ***） under copper ***（using Cucurbita ficifolia as rootstock） and ungrafted cucumber seedlings were cultured in deep flow technique（DFT） with the Cu2＋ concentration of 40 μmol *** results showed that on the 9th day of copper stress treatment,the contents of malondialdehyde（MDA） and hydrogen peroxide（H2O2）,superoxide radical（） producing rate,and electrolyte leakage percentage were significantly lower in grafted seedlings in comparison to those of the ungrafted seedlings,whereas the activities of antioxidants such as superoxide dismutase（SOD,EC 1.***.1.1）,peroxidase（POD,EC 1.***.1.7）,ascorbate peroxidase（APX,EC 1.***.1.11）,catalase（CAT,EC 1.***.1.6）,glutathione reductase（GR,EC 1.***.4.2）,and monodehydroascorbate reductase（MDHAR,EC 1.***.5.4） of grafted seedlings were also significantly higher than that of ungrafted seedlings,and the contents of free proline and soluble protein of grafted seedlings were significantly higher than that of ungrafted ***2＋ treatment increased the putrescine（Put） level and lowered the spermidine（Spd） and spermine（Spm） levels,thereby reducing the Put/（Spd ＋ Spm） ratio in leaves of grafted and ungrafted *** markedly reversed these Cu-induced effects for all three PAs and partially restored the Put/（Spd ＋ Spm） ratio in *** results suggest that grafting can enhance the tolerance of cucumber seedlings to Cu2＋ stress by increasing the activities of antioxidants and the levels of endogenous Spd and Spm,decreasing the Put/（Spd ＋ Spm） ratio and the levels of ROS,promoting free proline and soluble protein synthesis in cucumber seedling leaves.

关键词： copper stress grafted cucumber seedling antioxidant enzymes polyamines lipid peroxidation