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Preparation,characterization and catalytic behavior of hierachically porous CuO/α-Fe_2O_3/SiO_2 composite material for CO and o-DCB oxidation

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Journal of Natural Gas Chemistry 2011年第6期20卷 618-622页

作者： Xiaodong Ma Xi feng xuan He Hongwen Guo Lu Lu Key Laboratory of Environmental Pollution Process and Standard Ministry of Education Tianjin Key Laboratory of Environmental Remediation and Pollution Control College of Environmental Science and Engineering Nankai University Tianjin 300071 China

Hierachically porous （HP） CuO/α-Fe2O3/SiO2 composite material was fabricated by sol-gel method and multi-hydrothermal processes using HP-SiO2 as *** resulting material was characterized by N2 adsorption-desorption,X-ray diffraction and scanning electron *** as-prepared CuO/Fe2O3/HP-SiO2 sample,with α-Fe2O3 and CuO nanocrystals,possessed a co-continuous skeleton,through-macroporous and mesoporous *** catalytic behavior for CO and o-DCB oxidation was *** result showed that CuO/Fe2O3/HP-SiO2 catalyst exhibited high catalytic activity for both CO and o-DCB oxidation,indicating its potential application in combined abatement of CO and chlorinated volatile organic compounds.

关键词： CO and o-DCB oxidation hierachically porous CuO/α-Fe2O3/HP-SiO2 monolith

A review of physical supply and EROI of fossil fuels in China

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Petroleum Science 2017年第4期14卷 806-821页

作者： Jian-Liang Wang Jiang-xuan feng Yongmei Bentley Lian-Yong feng Hui Qu School of Business Administration China University of PetroleumBeijing 102249China University of Bedfordshire Business School Luton LUI 3JUUK Petroleum Industry Press CNPCBeijing lO0011China

This paper reviews China’s future fossil fuel supply from the perspectives of physical output and net energy output. Comprehensive analyses of physical output of fossil fuels suggest that China’s total oil production will likely reach its peak, at about 230 Mt/year(or 9.6 EJ/year),in 2018; its total gas production will peak at around350 Bcm/year(or 13.6 EJ/year) in 2040, while coal production will peak at about 4400 Mt/year(or 91.9 EJ/year)around 2020 or so. In terms of the forecast production of these fuels, there are significant differences among current studies. These differences can be mainly explained by different ultimately recoverable resources assumptions, the nature of the models used, and differences in the historical production data. Due to the future constraints on fossil fuels production, a large gap is projected to grow between domestic supply and demand, which will need to be met by increasing imports. Net energy analyses show that both coal and oil and gas production show a steady declining trend of EROI(energy return on investment) due to the depletion of shallow-buried coal resources and conventional oil and gas resources, which is generally consistent with the approaching peaks of physical production of fossil fuels. The peaks of fossil fuels production, coupled with the decline in EROI ratios, are likely to challenge the sustainable development of Chinese society unless new abundant energy resources with high EROI values can be found.

关键词： Peak production Fossil fuels Net energy EROI China

Automatically Identifying Calling-Prone Higher-Order Functions of Scala Programs to Assist Testers

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Journal of Computer Science & Technology 2020年第6期35卷 1278-1294页

作者： Yi-Sen Xu Xiang-Yang Jia Fan Wu Lingbo Li Ji-feng xuan School of Computer Science Wuhan UniversityWuhan 430072China Turing Intelligence Technology Limited LondonEC2Y 9STU.K.

For the rapid development of internetware, functional programming languages, such as Haskell and Scala, can be used to implement complex domain-specific applications. In functional programming languages, a higher-order function is a function that takes functions as parameters or returns a function. Using higher-order functions in programs can increase the generality and reduce the redundancy of source code. To test a higher-order function, a tester needs to check the requirements and write another function as the test input. However, due to the complex structure of higher-order functions, testing higher-order functions is a time-consuming and labor-intensive task. Testers have to spend an amount of manual effort in testing all higher-order functions. Such testing is infeasible if the time budget is limited, such as a period before a project release. In practice, not every higher-order function is actually called. We refer to higher-order functions that are about to be called as calling-prone ones. Calling-prone higher-order functions should be tested first. In this paper, we propose an automatic approach, namely PHOF, which predicts whether a higher-order function of Scala programs will be called in the future, i.e., identifying calling-prone higher-order functions. Our approach can assist testers to reduce the number of higher-order functions of Scala programs under test. In PHOF, we extracted 24 features from source code and logs to train a predictive model based on known higher-order function calls. We empirically evaluated our approach on 4832 higher-order functions from 27 real-world Scala projects. Experimental results show that PHOF based on the random forest algorithm and the Synthetic Minority Oversampling Technique Processing strategy (SMOTE) performs well in the prediction of calls of higher-order functions. Our work can be used to support the scheduling of limited test resources.

关键词： higher-order function testing tool test management Scala program internetware

Simulation and characteristics analysis of a wavefield in a thermoelastic medium adopting the rotated staggered-grid pseudospectral method and L-S theory

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Science China Earth Sciences 2021年第8期64卷 1390-1408页

作者： Yuanxie LI Cai LIU Zhiqi GUO Yang LIU xuan feng You TIAN Qi LU College of Geo-exploration Science and Technology Jilin UniversityChangchun 130026China

The simulation of wave propagation in high-temperature media requires thermoelastic *** this paper,we apply the rotated-staggered-grid pseudo-spectral method(RSG-PSM)to solving thermoelastic governing equations based on L-S theory.A time splitting method is used to solve the stiffness problem of the equations,and we introduce the rotated staggered pseudo-spectral operator and centered pseudo-spectral operator to compute the first-order spatial derivatives and second-order spatial derivatives,*** the case of the heterogeneous-medium model,the Crank-Nicolson explicit method is used instead of the pseudo-spectral method to compute the *** properties and propagation of the thermal coupled wavefield are discussed,and we compare the simulation results obtained using the pseudo-spectral method,staggered-grid pseudo-spectral method,and *** the case of an isotropic homogeneous medium,we obtain stable and highly accurate results using the time splitting method combined with the ***,the algorithm cannot be applied with a large time step when the thermal conductivity changes dramatically,and the algorithm is unstable when the reference temperature has a gradient *** optimal combined application of the mesh generation mode and numerical algorithm is explored,laying a foundation for the extension of these methods to thermoporoelasticity,thermoviscoelasticity,and anisotropy.

关键词： Thermoelastic wave L-S theory Rotated-staggered-grid pseudo-spectral method Seismic wavefield simulation Time splitting method

Analysis of photonic crystal fiber sensor character

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Optoelectronics Letters 2007年第3期3卷 199-202页

作者： GUO xuan LIU feng BI Wei-hong College of lnformation Science and Engineering Yanshan University Qinhuangdao 066004 China

The special character of a PCF which is used as a gas or liquid sensor is discussed. The field distribution is analyzed when the solid core PCF is injected with different medium that has different relative dielectric constant （or refractive index）. And the experiential formulas of the relation between refractive index of some kinds of liquid and their concentration are given, in order to measure the concentration of the relative liquid. At the same time, the effect of propagation constant on PCF sensor character is also discussed. Furthermore, the photonic medium relative dielectric constant, when it is injected with . band-gap （PBG） of PCF （PBG-PCF） is calculated at different different medium. That is the principle basis for this kind of PCF sensors.

关键词：光子晶体光纤传感器性能分析介电常数

Transition-Metal-Free Catalyzed Dehydrative Coupling of Quinoline and Isoquinoline N-Oxides with Propargylic Alcohols

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Chinese Journal of Chemistry 2022年第1期40卷 71-78页

作者： Zhao-Nan Cai Xiang-xuan feng Yuecheng Zhang Cong-Cong Lu Ya-Ping Han Jiquan Zhao School of Chemical Engineering and Technology Hebei University of TechnologyTianjin 300130China

A novel,green,and transition-metal-free protocol for the facile modification of quinoline and isoquinoline derivatives is introduced,starting from readily available and environmentally benign quinoline and isoquinoline N-oxides with propargylic alcohols in the presence of Na_(2)S_(2)O_(8) or K_(2)S_(2)O_(8) at 100℃.The one-pot transformation features the advantages of good functional group compatibility,short reaction time,operational simplicity,and highly efficient reaction *** protocol,which produces water as the only byproduct,provides efficient and atom-economical access to a class of fascinating quinoline and isoquinoline products in satisfactory *** method is effective on the gram scale,thus highlighting the inherent practicality of this methodology.

关键词： Synthetic methods Alcohols Nitrogen heterocycles Transition-metal-free Solvent-free

Short-term prone positioning for severe acute respiratory distress syndrome after cardiopulmonary bypass:A case report and literature review

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World Journal of Clinical Cases 2022年第36期10卷 13435-13442页

作者： Jian-Hua Yang Shu Wang Yuan-Xiu Gan xuan-Yun feng Bai-Lin Niu Department of Intensive Care Medicine Chongqing University Central HospitalChongqing Emergency Medical CenterChongqing Key Laboratory of Emergency MedicineChongqing 400016China Department of Intensive Care Medicine Chongqing University Central HospitalChongqing Emergency Medical CenterChongqing 400016China

BACKGROUND Aortic dissection is a complex and dangerous cardiovascular disease,with many complications in the perioperative period,including severe acute respiratory distress syndrome(ARDS),which affects prognosis and increases *** the effect of prone positioning(PP)in improving oxygenation in patients with severe ARDS,reports about PP early after cardiac surgery are few and such an opt-ion may be an issue in cardiac surgery patients because of the recent *** SUMMARY A 40-year-old male patient diagnosed with acute type A aortic dissection on October 22,2021 underwent ascending artery replacement plus total aortic arch replacement plus stent elephant trunk implantation under cardiopulmonary ***,he developed ARDS on postoperative day *** comprehensive treatment with aggressive pulmonary protective ventilation,fluid management with continuous renal replacement therapy,the condition continued to deteriorate and rapidly progressed to severe ARDS with a minimum oxygenation index of *** are ready to implement salvage therapy,including PP and extracorporeal membrane oxygenation(ECMO).Due to the large amount of pericardial mediastinal and thoracic drainage after thoracotomy,ECMO may result in massive postoperative *** prone ventilation is often inappropriate after ***,we chose short-term PP for<6 ***,the oxygenation index greatly improved and the diffuse exudation in both lungs of the patient was significantly reduced with short-term prone *** Intermittent short-term PP can improve early postoperative severe ARDS after acute aortic dissection.

关键词： Aortic dissection Short-term prone positioning Acute respiratory distress syndrome Oxygenation index Cardiopulmonary bypass Case report

Occurrence and risk assessment of typical PPCPs and biodegradation pathway of ribavirin in wastewater treatment plants

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Environmental Science and Ecotechnology 2022年第3期11卷 74-82页

作者： Qixin Liu xuan feng Ning Chen Fei Shen Haichuan Zhang Shuo Wang Zhiya Sheng Ji Li Jiangsu Key Laboratory of Anaerobic Biotechnology School of Environment and Civil EngineeringJiangnan UniversityWuxi214122China Laboratory of Instrumental Analysis Jiangsu Wuxi Environmental Monitoring CenterWuxi214121China Jiangsu Engineering Laboratory for Biomass Energy and Carbon Reduction Technology Jiangnan UniversityWuxi214122China Jiangsu College of Water Treatment Technology and Material Collaborative Innovation Center Suzhou215009China Department of Civil and Environmental Engineering University of AlbertaEdmontonT6G 2W2Canada

A large number of pharmaceuticals and personal care products(PPCPs)persist in wastewater,and the consumption of PPCPs for COVID-19 control and prevention has sharply increased during the *** study investigated the occurrence,removal efficiency,and risk assessment of six typical PPCPs commonly used in China in two wastewater treatment plants(WWTPs).Ribavirin(RBV)is an effective pharmaceutical for severely ill patients with COVID-19,and the possible biodegradation pathway of RBV by activated sludge was *** experimental results showed that PPCPs were detected in two WWTPs with a detection rate of 100%and concentrations ranging between 612 and 2323 ng L^(-1).The detection frequency and concentrations of RBV were substantially higher,with a maximum concentration of 314 ng L^(-1).Relatively high pollution loads were found for the following PPCPs from influent:ibuprofen>ranitidine hydrochloride>RBV>ampicillin sodium>clozapine>*** removal efficiency of PPCPs was closely related to adsorption and biodegradation in activated sludge,and the moving bed biofilm reactor(MBBR)had a higher removal capacity than the anoxic-anaerobic-anoxicoxic(AAAO)*** removal efficiencies of sulfamethoxazole,ampicillin sodium,ibuprofen,and clozapine ranged from 92.21%to 97.86%in MBBR process and were relatively low,from 61.82%to 97.62%in AAAO process,and the removal of RBV and ranitidine hydrochloride were lower than 42.96%in both MBBR and AAAO *** discrepancy in removal efficiency is caused by temperature,hydrophilicity,and hydrophobicity of the compound,and acidity and *** transformation products of RBV in activated sludge were detected and identified,and the biodegradation process of RBV could be speculated as follows:first breaks into TCONH_(2) and an oxygen-containing five-membered heterocyclic ring under the nucleosidase reaction,and then TCONH_(2) is finally formed into TCOOH through amide *** ecological risks

关键词： COVID-19 pandemic Ribavirin(RBV) Mass balance Pollution load estimation Risk assessment Biodegradation pathway

Utility of real-time 3D visualization system in the early stage of phacoemulsification training

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 577-582页

作者： Zhe Xu Dan Chen Jing-Wei Xu Yi-xuan feng Ce Shi Li Zhang Wen Xu Eye Center the Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009Zhejiang ProvinceChina Zhejiang Provincial Key Laboratory of Ophthalmology Hangzhou 310009Zhejiang ProvinceChina Zhejiang Provincial Clinical Research Center for Eye Diseases Hangzhou 310009Zhejiang ProvinceChina Zhejiang Provincial Engineering Institute on Eye Diseases Hangzhou 310009Zhejiang ProvinceChina

●AIM:To determine the teaching effects of a real-time three dimensional(3D)visualization system in the operating room for early-stage phacoemulsification training.●METHODS:A total of 10 ophthalmology residents of the first-year postgraduate were *** the residents were novices to cataract ***-time cataract surgical observations were performed using a custom-built 3D visualization *** training lasted 4wk(32h)in all.A modified International Council of Ophthalmology’s Ophthalmology Surgical Competency Assessment Rubric(ICO-OSCAR)containing 4 specific steps of cataract surgery was *** self-assessment(self)and expert-assessment(expert)were performed through the microsurgical attempts in the wet lab for each participant.●RESULTS:Compared with pre-training assessments(self 3.2±0.8,expert 2.5±0.6),the overall mean scores of posttraining(self 5.2±0.4,expert 4.7±0.6)were significantly improved after real-time observation training of 3D visualization system(P<0.05).Scores of 4 surgical items were significantly improved both self and expert assessment after training(P<0.05).●CONCLUSION:The 3D observation training provides novice ophthalmic residents with a better understanding of intraocular microsurgical *** is a useful tool to improve teaching efficiency of surgical education.

关键词： 3D visualization system phacoemulsification training wet lab