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Petroleum Science 2018年第3期15卷 644-656页

作者： jie-Hui yuan Sheng Zhou Tian-Duo Peng Ge-Hua Wang Xun-Min Ou Institute of Energy Environment and Economy Tsinghua University China Automotive Energy Research Centre Tsinghua University

This study develops a bottom-up model to quantitatively assess the comprehensive effects of replacing traditional petroleum-powered vehicles with natural gas vehicles（NGVs） in China based on an investigation of the direct energy consumption and critical air pollutant（CAP） emission intensity, life-cycle energy use and greenhouse gas（GHG） emission intensity of NGV fleets. The results indicate that, on average, there are no net energy savings from replacing a traditional fuel vehicle with an NGV. Interestingly, an NGV results in significant reductions in direct CAP and life-cycle GHG emissions compared to those of a traditional fuel vehicle, ranging from 61% to 76% and 12% to 29%, respectively. Due to the increasing use of natural gas as a vehicle fuel in China（i.e. approximately 28.2 billion cubic metres of natural gas in2015）, the total petroleum substituted with natural gas was approximately 23.8 million tonnes（Mt）, which generated a GHG emission reduction of 16.9 Mt of CO2 equivalent and a CAP emission reduction of 1.8 Mt in 2015. Given the significant contribution of NGVs, growing the NGV population in 2020 will further increase the petroleum substitution benefits and CAP and GHG emission reduction benefits by approximately 42.5 Mt of petroleum-based fuel, 3.1 Mt of CAPs and 28.0 Mt of GHGs. By 2030, these benefits will reach 81.5 Mt of traditional petroleum fuel, 5.6 Mt of CAPs and 50.5 Mt of GHGs, respectively.

关键词： Natural gas vehicles Energy use Greenhouse gases Critical air pollutants China Life-cycle analysis

Magnetic nanoparticles used in headspace extraction coupled with DSI-GC-IT/MS for analysis of VOCs in dry Traditional Chinese Medicine

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Chinese Chemical Letters 2016年第1期27卷 178-184页

作者： Jing Nie yuan-jie Teng Zu-Guang Li Wen-Han Liu Maw-Rong Lee College of Chemical Engineering Zhejiang University of Technology Department of Chemistry National Chung-Hsing University

A novel magnetic method using polystyrene modified magnetic nanoparticles to perform thermoheadspace extraction was successfully developed for extraction and preconcentration of volatile organic components in dry Traditional Chinese Medicine（TCM） based on gas chromatography-ion trap/mass spectrometry with a Chromato Probe direct sample introduction device. The dried fruit of Amomum testaceum Ridl. was used as the object TCM. The optimum parameters of headspace magnetic solid-phase extraction were investigated, in which desorption solvent ethyl acetate played a key role in this method,and the headspace extraction temperature of 90℃ and the headspace extraction time of 15 min finally decided. Headspace solid-phase microextraction method was also used to analyze volatile compounds in the TCM to compare with the proposed method. The results show that 60 components were identified totally by two methods; most of the low boiling point chemical compounds are isolated by this new method. In this work, an environmental-friendly and cheap analytical method was established, and a new approach to analyze volatile compounds in dry Traditional Chinese Medicine was also provided.

关键词： Magnetic nanoparticles Direct sample introduction Volatile components Traditional Chinese Medicine

Review of some recent progress on materials science researches in China

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Science China Chemistry 2012年第12期55卷 2497-2502页

作者： TANG Mei GUO YingQing yuan jie WEI Qin SUN ShuJun ZHOU Wei ZHANG Yue Materials Science&Engineering School Beihang UniversityBeijing 100191China School of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing 210037China School of Civil Engineering Southeast UniversityNanjing 210096China National Natural Science Foundation of China Beijing 100085China Beijing Institute of Aeronautics Material Beijing 100095China College of Chemistry Chemical Engineering and Materials ScienceHeilongjiang UniversityHarbin 150080China

New materials have become one of the most important and fastest-growing industries all over the *** progress in materials science and technology has produced profound influences on the national economy,daily life and national defense of our *** this paper,we review the state of the art of materials science and technology in China,with emphasis on recent research focuses and advanced technology.

关键词： nano-materials semiconductor materials superconducting materials cement ceramic alloy intelligent materials

Laboratory Testing of Magnetic Tracers for Soil Erosion Measurement

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Pedosphere 2011年第3期21卷 328-338页

作者： HU Guo-Qing DONG yuan- jie WANG Hui QIU Xian-Kui WANG Yan-Hua College of Resources and Environment Shandong Agricultural University Tai'an 271018 (China)

Soil erosion, which includes soil detachment, transport, and deposition, is one of the important dynamic land surface processes. The magnetic tracer method is a useful method for studying soil erosion processes. In this study, five types of magnetic tracers were made with fine soil, fly ash, cement, bentonite, and magnetic powder （reduced iron powder） using the method of disk granulation. The tracers were uniformly mixed with soil and tested in the laboratory using simulated rainfall and inflow experiments to simulate the interrill and rill components of soil erosion, in order to select one or more tracers which could be used to study detachment and deposition by the erosive forces of raindrops and surface flow of water on a slope. The results showed that the five types of magnetic tracers with high magnetic susceptibility and a wide range of sizes had a range of 0.99-1.29 gcm-3 in bulk density. In the interrill and rill experiments, the tracers FC1 and FC2 which consisted of fly ash and cement at ratios of 1：1 and 2：1, respectively, were transported in phase with soil particles since the magnetic susceptibility of sediment approximated that of the soil which was uneroded and the slopes of the regression equations between the detachment of sediment and magnetic tracers FC1 and FC2 were very close to the expected value of 20, which was the original soil/tracer ratio. The detachment and deposition on slopes could be accurately reflected by the magnetic susceptibility differences. The change in magnetic susceptibility depended on whether deposition or detachment occurred. However, the tracer FS which consisted of fine soil and the tracers FB1 and FB2 which consisted of fly ash and bentonite at ratios of 1：1 and 2：1, respectively, were all unsuitable for soil erosion study since there was no consistent relationship between sediment and tracer detachment for increasing amounts of runoff. Therefore, the tracers FC1 and FC2 could be used to study soil erosion by water.

关键词： magnetic susceptibility interrill erosion rill erosion runoff sediment

A Theoretical Insight into the Mechanism of Cu（I）-Catalyzed C--N Coupling between Aryl Halides and Aqueous Ammonia

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Chinese Journal of Chemistry 2015年第8期33卷 961-966页

作者： Ting Chen Mingkuan Yan Chao Zheng jie yuan Shen Xu Runfeng Chen Wei Huang Key Laboratory for Organic Electronics and Information Displays & Institute of Advanced Materials Jiangsu National Synergistic Innovation Center for Advaneed Materials Nanjing University of Posts & Telecommunications Nanjing Jiangsu 210023 China Key Laboratory of Flexible Electronics & Institute of Advanced Materials Jiangsu National Synergistic Innovation Center for Advanced Materials Nanjing Tech University Nanjing Jiangsu 211816 China

Computational investigations of Cu（I）-catalyzed C--N coupling between aryl halides and aqueous ammonia without addition of any base or ligand were reported. Density functional theory calculations were performed to re- veal the mechanism of the ligand-free amination reaction for the preparation of primary aromatic amines. Through systematic evaluation of the relative concentrations of possible Cu species in solution, we propose that the active catalyst is the neutral Cu（I） complexes rather than the Cu（I） cations; oxidative addition of aryl bromide is a facile step of the catalytic cycle; reactant （NH3） and solvent molecule （NMP） can act as ligands of Cu species to help re- duce the activation energy of the forward reaction and increase the activation energy of the reverse reaction; except for Pathway B, the deprotonation step is irreversible due to the extreme exothermic feature; the elimination of H20 is kinetically favored, while that of HBr is thermodynamically preferred. These findings should be valuable for the mechanism understandings of the ligand-free Cu-catalyzed C--N cross-coupling reactions and for the further de- velopment of highly efficient amination catalyst systems.

关键词： amination C-N cross coupling Cu(I)-catalyzed coupling DFT catalytic mechanism

Tunable superconductivity in parent cuprate Pr_2CuO_(4±δ) thin films

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Chinese Physics B 2019年第5期28卷 276-281页

作者： Xinjian Wei Ge He Wei Hu Xu Zhang Mingyang Qin jie yuan Beiyi Zhu yuan Lin Kui Jin Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences School of Physical Sciences University of Chinese Academy of Sciences Songshan Lake Materials Laboratory State Key Laboratory of Electronic Thin Films and Integrated Devices & Center for Information in Medicine University of Electronic Science and Technology of China Collaborative Innovation Center of Quantum Matter

We studied the role of oxygen in Pr2 CuO_(4±δ) thin films fabricated by the polymer assisted deposition method. The magnetoresistance and Hall resistivity of Pr2 CuO_(4±δ) samples were systematically investigated. It was found that with decreasing oxygen content, the low-temperature Hall coefficient(RH) and magnetoresistance changed from negative to positive, similar to those with the increase of Ce-doped concentration in R_(2-x)Ce_x CuO_4 (R = La, Nd, Pr, Sm, Eu). In addition, we observed that the dependence of the superconducting critical temperature Tc with RH for the Pr_(2-x) Ce_x CuO_4 perfectly overlapped with that of Pr_2 CuO_(4±δ) . These findings point to the fact that the doped electrons induced by the oxygen removal are responsible for the superconductivity of the T-phase parent compounds.

关键词： Pr2CuO4±δ thin film superconductivity polymer assisted deposition

The mobility improvement of organic thin film transistors by introducing Zn O-nanrods as an zctive layer

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Science China(Technological Sciences) 2016年第5期59卷 714-720页

作者： XIE Tao XIE Guang Zhong DU Hong Fei YE Zong Biao SU yuan jie CHEN Yu Yan School of Optoelectronic Information State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China (UESTC)

Organic thin film transistors(OTFTs) based on poly(3-hexylthiophene)(P3HT)/Zinc oxide(ZnO) nanorods composite films as the active layers were prepared by spray-coating process. The OTFTs with P3HT/ZnO-nanorods composite films owned higher carriers mobility than the OTFT based on pure P3 HT. It can be found that the mobility of OTFTs increased by 135% due to ZnO-nanorods doping. This was attributed to the improvement of the P3 HT crystallinity and the optimization of polymer chains orientation. Meanwhile, because of the distinction of work function between P3 HT and ZnO, the majority carriers would accumulate on either side of the P3HT-ZnO interface which benefited carrier transfer. The influence on the mobility of composite film was studied. In addition, the threshold voltage of devices changed positively with the increase of ZnO-nanorods due to the decrease of electrostatic potential for P3HT/ZnO-nanorods composite films. The effect could be explained by the energy level theory of semiconductor.

关键词： P3HT ZnO-nanorods composite film OTFT

Fast three-dimensional radiation field characterization in largescale nuclear installations

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Nuclear Science and Techniques 2017年第5期28卷 53-59页

作者： yuan-jie Bi Zhi-Ping Luo Jin-Sen Guo Chuan-Long Li Hong-Wei Yang Ling Chen China Institute of Atomic Energy Beijing 102413 China

The requirement of the fast three-dimensional radiation field calculation is raised during the decommissioning of large-scale nuclear installations. The most often used methods, such as the Monte Carlo and the discrete ordinates methods, have shortcomings in their simulations of such problems. The coupled Monte Carlo–point kernel computational scheme is developed to meet the requirement. The facility is separated into the source region and the bulk shielding region, with a common interface. The transport within the source region is simulated using the Monte Carlo method, which is by nature good at treating complex geometries. The radiation field in the bulk shielding region is treated by the point kernel approach to avoid the extremely expensive computation for deep penetration problems. The flow rate through the interface,which is given by the Monte Carlo simulation, is considered as the equivalent surface source for the point kernel calculation. Test calculations from simplified typical waste storage facilities have been performed to validate the coupled scheme by comparing them with the results conducted by the Monte Carlo method directly. The good agreement of the results, as well as the significant saving in computing time, indicates that the coupled method is suitable for the fast three-dimensional radiation field calculation.

关键词： Fast radiation field calculation Point kernel approach Monte Carlo method Coupled computational scheme

Probing structural and electronic properties of divalent metal Mg_(n+1) and SrMgn (n=2–12) clusters and their anions

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Chinese Physics B 2022年第1期31卷 465-471页

作者： Song-Guo Xi Qing-Yang Li Yan-Fei Hu Yu-Quan yuan Ya-Ru Zhao Jun-jie yuan Meng-Chun Li Yu-jie Yang School of Physics and Electronic Engineering Sichuan University of Science&EngineeringZigong 643000China Department of Applied Physics Chengdu University of TechnologyChengdu 610059China College of Physics&Optoelectronics Technology Baoji University of Arts and SciencesBaoji 721016China

Divalent metal clusters have received great attention due to the interesting size-induced nonmetal-to-metal transition and fascinating properties dependent on cluster size,shape,and *** this work,the combination of the CALYPSO code and density functional theory(DFT)optimization is employed to explore the structural properties of neutral and anionic Mg_(n+1) and SrMgn(n=2-12)*** results exhibit that as the atomic number of Mg increases,Sr atoms are more likely to replace Mg atoms located in the skeleton convex *** analyzing the binding energy,second-order energy difference and the charge transfer,it can be found the SrMg9 cluster with tower framework presents outstanding stability in a studied size ***,bonding characteristic analysis reveals that the stability of SrMg9 can be improved due to the strong s-p interaction among the atomic orbitals of Sr and Mg atoms.

关键词： SrMgn(n=2-12)clusters CALYPSO code density functional theory(DFT)optimization

Synthesis and properties of potassium 5,5'-azobis(1-nitraminotetrazolate)：A green primary explosive with superior initiation power

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Chinese Chemical Letters 2017年第1期28卷 117-120页

作者： Ya-Nan Li Bo-Zhou Wang yuan-jie Shu Lian-jie Zhai Sheng-Yong Zhang Fu-Qiang Bi Yu-Chuan Li Key Laboratory of Fluorine&Nitrogen Chemicals Xi'an Modern Chemistry Research InstituteXi'an 710065China School Of Material Science&Engineering Beijing Institute of TechnologyBeijing 100081China

Potassium 5,5＇-azobis（1-nitraminotetrazolate）,（K2ABNAT）, a new green primary explosive, was synthesized via a safe and convenient synthetic procedure based on methylcarbazate and cyanogen azide. The compound was characterized by single-crystal X-ray diffraction, IR spectroscopy, Raman spectroscopy, multinuclear NMR spectroscopy, elemental analysis, and differential scanning calorimetry（DSC）. With the calculated（CBS-4M） heat of formation（617.0 kJ/mol） and the room temperature X-ray density（2.11 g/cm^3）, impressive values for the detonation parameters such as detonation velocity（8367 m/s） and pressure（31.5 GPa） were computed using the EXPLO5 program. The superior calculated energetic performance show it could serve as a green replacement for the widely used primary explosive,lead（II） azide, which contains toxic ingredient.

关键词： Energetic materials Tetrazole Azo compounds Nitroamines Primary explosives