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Journal of Environmental Sciences 2011年第10期23卷 1729-1737页

作者： xun pan Zhimin Qiang Weiwei Ben Meixue Chen Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

This work describes a systematic approach to the development of a method for simultaneous determination of three classes of veterinary antibiotics in the suspended solids （SS） of swine wastewater, including five sulfonamides, three tetracyclines and one macrolide （tiamulin）. The entire procedures for sample pretreatment, ultrasonic extraction （USE）, solid-phase extraction （SPE）, and liquid chromatography-mass spectrometry （LC-MS） quantification were examined and optimized. The recovery efficiencies were found to be 76%-104% for sulfonamides, 81%-112% for tetracyclines, and 51%--64% for tiamulin at three spiking levels. The intra-day and inter-day precisions, as expressed by the relative standard deviation （RSD）, were below 17%. The method detection limits （MDLs） were between 0.14 and 7.14 μg/kg, depending on a specific antibiotic studied. The developed method was applied to field samples collected from three concentrated swine feeding plants located in Beijing, Shanghai and Shandong province of China. All the investigated antibiotics were detected in both SS and liquid phase of swine wastewater, with partition coefficients （logKd） ranging from 0.49 to 2.30. This study demonstrates that the SS can not be ignored when determining the concentrations of antibiotics in swine wastewater.

关键词： antibiotics swine wastewater suspended solids ultrasonic extraction solid-phase extraction mass spectrometry

Some New Solutions of Jacobi Elliptic Functions to mBBM Equation

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Communications in Theoretical Physics 2007年第5X期48卷 787-790页

作者： GONG Lun-xun pan Jun-Ting School of Science Guizhou Normal University Guiyang 550001 China

The modified mapping method is further improved by the expanded expression of u（ξ） that contains the terms of the first-order derivative of function f（ξ）. Some new exact solutions to the mBBM equation are determined by means of the method. We can obtain many new solutions in terms of the Jacobi elliptic functions of the equation.

关键词： further improved modified mapping method traveling wave solutions Jacobi elliptic functions

Some New Solitary Wave Solutions to a Compound KdV-Burgers Equation

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Communications in Theoretical Physics 2008年第7期50卷 51-52页

作者： GONG Lun-xun pan Jun-Ting School of Science Guizhou Normal University Guiyang 550001 China

Abstract In terms of the solutions of an auxiliary ordinary differential equation, a new algebraic method, which contains the terms of first-order derivative of functions f （ξ）, is constructed to explore the new solitary wave solutions for nonlinear evolution equations. The method is applied to a compound KdV-Burgers equation, and abundant new solitary wave solutions are obtained. The algorithm is also applicable to a large variety of nonlinear evolution equations.

关键词： traveling wave solutions compound KdV-Burgers equation solitary wave solution

A New Algebraic Method and Its Application to Nonlinear Klein-Gordon Equation

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Communications in Theoretical Physics 2008年第12期50卷 1276-1278页

作者： GONG Lun-xun pan Jun-Ting School of Science Guizhou Normal University Guiyang 550001 China

In terms of the solutions of the generalized Riccati equation,a new algebraic method,which contains theterms of radical expression of functions f(ξ),is constructed to explore the new exact solutions for nonlinear *** concise and straightforward,the method is applied to nonlinear Klein Gordon equation,and some newexact solutions of the system are *** method is of important significance in exploring exact solutions for othernonlinear evolution equations.

关键词： generalized Riccati equation travelling wave solutions nonlinear Klein-Gordon equation exactsolution

Adsorption behavior of sulfamethazine in an activated sludge process treating swine wastewater

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Journal of Environmental Sciences 2014年第8期26卷 1623-1629页

作者： Weiwei Ben Zhimin Qiang Xiaowei Yin Jiuhui Qu xun pan Key Laboratory of Aquatic Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of Sciences Foreign Economic Cooperation Office Ministry of Environmental Protection

Swine wastewater is an important pollution source of antibiotics entering the aquatic environment. In this work,the adsorption behavior of sulfamethazine（SMN）,a commonlyused sulfonamide antibiotic,on activated sludge from a sequencing batch reactor treating swine wastewater was investigated. The results show that the adsorption of SMN on activated sludge was an initially rapid process and reached equilibrium after 6 hr. The removal efficiency of SMN from the water phase increased with an increasing concentration of mixed liquor suspended solids,while the adsorbed concentration of SMN decreased. Solution pH influenced both the speciation of SMN and the surface properties of activated sludge,thus significantly impacting the adsorption process. A linear partition model could give a good fit for the equilibrium concentrations of SMN at the test temperatures（i.e.,10,20 and 30°C）. The partition coefficient（Kd） was determined to be 100.5 L/kg at 20°C,indicating a quite high adsorption capacity for SMN. Thermodynamic analysis revealed that SMN adsorption on activated sludge was an exothermic process. This study could help to clarify the fate and behavior of sulfonamide antibiotics in the activated sludge process and assess consequent environmental risks arising from sludge disposal as well.

关键词： Sulfonamide antibiotics Activated sludge Adsorption Swine wastewater treatment

Comparison and analysis of mitigation ambitions of Parties’ updated Nationally Determined Contributions

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Advances in Climate Change Research 2023年第1期14卷 4-12页

作者： Hai-Lin WANG Yu-Yan WENG xun-Zhang pan Institute of Energy Environment and EconomyTsinghua UniversityBeijing 100084China Think Tank Center Tsinghua UniversityBeijing 100084China School of Economics and Management China University of PetroleumBeijing 102249China

Understanding mitigation ambitions of the Nationally Determined Contributions(NDCs)should include both the equity of supporting the Paris Agreement goals and the costs of achieving the proposed mitigation *** study presents a new framework that combines equity and economic costs to compare and analyze mitigation ambitions of Parties'updated *** representative 2℃ and 1.5℃ pathways,this framework uses multiple equity-principled allocations to derive the alignment of the updated NDCs with the Paris Agreement goals,and further applies a computable general equilibrium model to assess the economic costs of implementing the updated *** results show that global 2030 emissions may meet the selected global 2℃ pathway if all Parties achieve their most ambitious mitigation efforts,but there is still an emissions gap of 10-15 GtCO_(2) to follow the selected 1.5℃ *** the perspective of equity,the updated NDCs of the USA,the EU(including the UK in this study),and Japan lack ambition with respect to‘equal cumulative per capita emissions’under 2℃ and do not align with any equity principles under 1.5℃.The updated NDCs of China,India,Brazil and South Africa reflect their claims to‘equity’and‘common but differentiated responsibilities’.From the perspective of economic costs,the GDP and welfare losses of China,Brazil and South Africa incurred by achieving the updated NDCs are not lower than those of the three developed ***'s GDP loss is estimated at 0.43%-0.55%in 2030,which is higher than that of the USA(0.30%-0.38%)and the EU(0.25%-0.28%).This study suggests that developed Parties take the lead in further ratcheting up the NDCs and strengthen financial and technological support to developing countries so that the world could close the gap to 1.5℃.

关键词： Updated NDCs 2030 emissions Equity Economic costs Paris Agreement

Adsorptive removal of antibiotics from water using magneticion exchange resin

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Journal of Environmental Sciences 2017年第2期29卷 111-117页

作者： Tianyue Wang xun pan Weiwei Ben Jianbing Wang Pin Hou Zhimin Qiang Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Enuironmental SciencesChinese Academy of SciencesBeijing 100085China School of Chemical and Enuironmental Engineering Beijing CampusChina University of Mining and TechnologyBeijing 100083China Foreign Economic Cooperation Office Ministry of Environmental ProtectionBeijing 100035China

The occurrence of antibiotics in the environment has recently raised serious concern regarding their potential threat to aquatic ecosystem and human health. In this study, the magnetic ion exchange（MIEX） resin was applied for removing three commonly-used antibiotics, sulfamethoxazole（SMX）, tetracycline（TCN） and amoxicillin（AMX） from *** results of batch experiments show that the maximum adsorption capacities on the MIEX resin for SMX, TCN and AMX were 789.32, 443.18 and 155.15 μg/m L at 25°C,respectively, which were 2–7 times that for the powdered activated carbon. The adsorption kinetics of antibiotics on the MIEX resin could be simulated by the pseudo-second-order model（R^2= 0.99）, and the adsorption isotherm data were well described by the Langmuir model（R^2= 0.97）. Solution p H exhibited a remarkable impact on the adsorption process and the absorbed concentrations of the tested antibiotics were obtained around the neutral p *** MIEX resin could be easily regenerated by 2 mol/L Na Cl solution and maintained high adsorption removal for the tested antibiotics after regeneration. Anion exchange mechanism mainly controlled the adsorption of antibiotic and the formation of hydrogen binding between the antibiotic and resin can also result in the increase of adsorption capacity. The high adsorption capacity, fast adsorption rate and prominent reusability make the MIEX resin a potential adsorbent in the application for removing antibiotics from water.

关键词： Sulfamethoxazole Tetracycline Amoxicillin Antibiotics MIEX resin Adsorption

Understanding equityeefficiency interaction in the distribution of global carbon budgets

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Advances in Climate Change Research 2023年第1期14卷 13-22页

作者： xun-Zhang pan Fei TENG Yann ROBIOU DU PONT Hai-Lin WANG School of Economics and Management China University of PetroleumBeijing 102249China Institute of Energy Environment and EconomyTsinghua UniversityBeijing 100084China Institute for Sustainable Development and International Relations Sciences PoParis 75007France Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

Equity and efficiency are two important factors guiding the mitigation of anthropogenic emissions to achieve the Paris climate *** studies have proposed a range of allocations of global carbon budgets,but few have quantified the equity-efficiency *** on an investigation of the existing allocation literature,this study conducts a novel analysis using a‘mixed’allocation‘big-data’framework to understand the equityeefficiency interaction in the distribution of global carbon budgets under 2℃ and 1.5℃ warming *** a global scale,a carbon Gini coefficient and aggregate abatement costs are used as quantitative metrics to reflect equity and efficiency,*** show an equity-efficiency frontier that reflects the opportunity for the international community to co-improve equity and efficiency on top of existing ***,the frontier also features strong trade-offs to further improve equity and efficiency if national allocations are to be achieved *** analysis verifies that such trade-offs are sensitively dependent on the level of global connection and *** national mitigation actions and potentials can help promote equity-efficiency synergies and contribute to the efficient achievement of the Paris Agreement's temperature and equity goals.

关键词： Equity-efficiency interaction Global carbon budgets Paris climate goals Cooperation and finance Frontier analysis

Multiblock poly(ether-b-amide)copolymers comprised of PA1212 and PPO-PEO-PPO with specific moisture-responsive and antistatic properties

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Chinese Journal of Chemical Engineering 2023年第1期53卷 421-430页

作者： Jie Jiang Wei Cheng Qiuyu Tang xun pan Jinjin Li Ling Zhao Zhenhao Xi Weikang Yuan State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast ChinaUniversity of Science and TechnologyShanghai 200237China Shanghai Key Laboratory of Multiphase Materials Chemical Engineering East China University of Science and TechnologyShanghai 200237China Flinders Institute for Nanoscale Science and Technology Flinders UniversitySA 5042Australia College of Chemistry and Chemical Engineering Xinjiang UniversityUrumqi 830046China

Functional multiblock poly(ether-b-amide)(PEBA)copolymers,comprised of PA1212(polyamide 1212)as hard segments and Jeffamine ED-2003 as soft segments,were successfully prepared via two-step melt polycondensation without any amidation ***,using diamino-terminated poly(propylene oxide)-poly(ethylene oxide)-poly(propylene oxide)(PPO-PEO-PPO),Jeffamine ED-2003,enhances the compatibility between polyamide oligomer and polyether,which is better than the traditional route using hydroxyl-terminated *** chemical structure of multiblock PEBAs,as well as the microphase separated structure with crystalline phase of polyamide and polyether,were confirmed by heteronuclear multiple-bond correlation spectrum,heteronuclear multiple quantum correlation spectrum,Fourier transform infrared spectroscopy(FT-IR),differential scanning calorimetry and dynamic mechanical *** hydrophilic PEBA copolymers showed water adsorption ranging from 87.3%to 17.1%depending on the polyether content,and specially showed moisture responsive behavior within seconds when exposed to *** corresponding mechanism was studied using time-resolved attenuated total reflectance FT-IR spectroscopy in the molecular level and the water diffusion coefficient was estimated to be 1.07×10^(–8)cm^(2)∙s^(-1).Two-dimensional correlation FT-IR spectra analysis was performed to confirm that the interaction between water and polyether phase was in preference to that between water and polyamide matrix,and water molecule only forms hydrogen bond with the polyether *** to the incorporation of PEO segments,the PEBAs have the surface resistivity varying from 5.6×10^(9)to 6.5×10^(10)Ω,which makes PEBA potential candidate as permanent antistatic agent.

关键词： Poly(ether-b-amide)s Moisture-responsive Antistatic In situ FT-IR 2D FT-IR analysis

Spillover of international crude oil prices on China's refined oil wholesale prices and price forecasting:Daily-frequency data of private enterprises and local refineries

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Petroleum Science 2022年第3期19卷 1433-1442页

作者： xun-Zhang pan Xi-Ran Ma Li-Ning Wang Ya-Chen Lu Jia-Quan Dai Xiang Li School of Economics and Management China University of PetroleumBeijing 102249China Economics&Technology Research Institute China National Petroleum CorporationBeijing 100724China Key Laboratory of Oil and Gas Market Simulation and Price Forecasting China National Petroleum CorporationBeijing 100724China Institue of Energy Peking UniversityBeijing 100080China

Compared with retail prices of state-owned companies used in almost all existing studies,China’s refined oil wholesale prices of private enterprises and local refineries are more affected by the market and better reflect the real supply-demand *** the first time,this paper applies own-monitored dailyfrequency wholesale prices of China’s private enterprises and local refineries during 2013-2020 to derive spillover effects of international crude oil prices on China’s refined oil prices through the VAR-BEKKGARCH(vector autoregression-Baba,Engle,Kraft,and Kroner-generalized autoregressive conditional heteroscedasticity)model,and then tries to forecast wholesale prices through the PCA-BP(principal component analysis-back propagation)neural network *** show that international crude oil prices have significant mean spillover and volatility spillover effects on China’s refined oil wholesale *** in crude oil prices are the Granger cause of changes in refined oil wholesale *** the improvement of China’s oil-pricing mechanism in 2016,the volatility spillover from the international crude oil market to China’s refined oil market gradually increases,and the BRENT price variation has an increasing impact on the refined oil wholesale price *** PCA-BP model could serve as a candidate tool for forecasting China’s refined oil wholesale prices.

关键词： Own-monitored daily-frequency data Refined oil wholesale prices Spillover effects VAR-BEKK-GARCH PCA-BP neural Network