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Prioritizing chemicals for environmental management in China based on screening of potential risks

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Frontiers of Earth Science 2014年第1期8卷 104-114页

作者： Xiangyi yu yan MAO Chemical Registration Center of Ministry of Environmental Protection Beijing 100012 China

The rapid development of China＇s chemical industry has created increasing pressure to improve the environmental management of chemicals. To bridge the large gap between the use and safe management of chemicals, we performed a comprehensive review of the international methods used to prioritize chemicals for environmental management. By comparing domestic and foreign methods, we confirmed the presence of this gap and identified potential solutions. Based on our literature review, we developed an appropriate screening method that accounts for the unique characteristics of chemical use within China. The proposed method is based on an evaluation using nine indices of the potential hazard posed by a chemical： three environmental hazard indices （persistence, bioaccumulation, and eco-toxicity）, four health hazard indices （acute toxicity, carcinogenicity, mutagenicity, and reproductive and developmental toxi- city）, and two environmental exposure hazard indices （chemical amount and utilization pattern）. The results of our screening agree with results of previous efforts from around the world, confirming the validity of the new system. The classification method will help decision- makers to prioritize and identify the chemicals with the highest environmental risk, thereby providing a basis for improving chemical management in China.

关键词： chemicals screening risk environmental management priority definition

Study on Dynamic Characteristics of Hydraulic Pumping Unit on Offshore Platform

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China Ocean Engineering 2017年第6期31卷 693-699页

作者： CHANG Zong-yu yu yan-qun QI Yao-guang College of Engineering Ocean University of ChinaQingdao 266100China College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China

A new technology of offshore oil rod pumping production is developed for offshore heavy oil recovery. A new type of miniature hydraulic pumping unit with long-stroke, low pumping speed and compact structure is designed based on the spatial characteristics of offshore platforms. By combining the strengths of sinusoidal velocity curve and trapezoidal velocity curve, a kinematical model of the acceleration, the velocity and displacement of the pumping unit＇s hanging point is established. The results show that the pumping unit has good kinematic characteristics of smooth motion and small dynamic load. The multi-degree-of-freedom dynamic model of the single-well pumping unit is established. The first and second order natural frequencies of the sucker rod string subsystem and the pumping unit subsystem are studied. The results show that the first and the second order natural frequencies among the pumping rod string, pumping unit-platform subsystem and the dynamic excitation have differences over 5 times from each other, indicating that resonance phenomenon will not appear during the operation and the dynamic requirements for field use are met in the system.

关键词： offshore platform platform pumping unit kinematic model dynamic model multiple degrees of freedom

Recent Progress on Modification Strategies of Alloy-based Anode Materials for Alkali-ion Batteries

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Chemical Research in Chinese Universities 2021年第2期37卷 200-209页

作者： WU Ying YAO yu WANG Lifeng yu yan Hefei National Laboratory for Physical Sciences at the Microscale Department of Materials Science and EngineeringCAS Key Laboratory of Materials for Energy ConversionUniversity of Science and Technology of ChinaHefei230026P.R.China Dalian National Laboratory for Clean Energy(DNL) Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023P.R.China

Alkali-ion batteries,including lithium-ion batteries(LIBs),sodium-ion batteries(NIBs)and potassium-ion batteries(KIBs),with alloy-based anodes exhibit huge potential in high energy density due to the natural abundance,high theoretical capacity as well as suitable operating ***,the practical application is severely hindered by the huge volume variation based on the alloying mechanism and inferior conductivity,especially for red phosphorus(P)and silicon(Si)anodes,which induces poor rate capability and fast capacity ***,we will briefly review fundamental advantages and challenges of alloy-based anode ***,effective modification strategies of alloy-based anode materials for boosting the performance would be emphasized and ***,we will share our perspectives and some opportunities to obtain high-performance alloy-based anode materials for further application.

关键词： Alloy-based anode Alkali-ion battery Modification strategy

Effects of PEG Molecular Weight on Its Interaction with Albumin

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Chinese Journal of Polymer Science 2015年第10期33卷 1373-1379页

作者： Jing-jing Lai Huai-yu yan yan Liu 黄延宾 Key Laboratory of Advanced Materials(MOE) Department of Chemical Engineering Tsinghua University

The fluorescence property of bovine serum albumin was investigated in the presence of PEGs of different molecular weights. Based on our results, we propose that PEGs of different molecular weights bind to albumin in the pH 7.4 aqueous solution, but only when the polymer size is larger than the protein size, one polymer chain may bind to multiple proteins and cause the proteins to aggregate.

关键词： Polyethylene glycol Bovine serum albumin Protein-polymer interactions Fluorescence analysis

Operation of a Rotary-valved Pulse Detonation Rocket Engine Utilizing Liquid-kerosene and Oxygen

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Chinese Journal of Aeronautics 2011年第6期24卷 726-733页

作者： WANG Ke FAN Wei yan yu ZHU Xudong yan Chuanjun School of Power and Energy Northwestern Polytechnical University Xi ＇an 710072 China

The pulse detonation rocket engine （PDRE） requires periodic supply of oxidizer, fuel and purge gas. A rotary-valve assembly is fabricated to control the periodic supply in this research. Oxygen and liquid aviation kerosene are used as oxidizer and fuel respectively. An ordinary automobile spark plug, with ignition energy as low as 50 mJ, is used to initiate combustion. Steady operation of the PDRE is achieved with operating frequency ranging from 1 Hz to 10 Hz. Experimentally measured pressure is lower than theoretical value by 13% at 1 Hz and 37% at 10 Hz, and there also exists a velocity deficit at different operating frequencies. Both of these two phenomena are believed mainly due to droplet size which depends on atomization and vaporiza-tion of liquid fuel.

关键词： pulse detonation rocket engines rotary-valve velocity deficit kerosene oxygen

Oil Body Biogenesis during Brassica napus Embryogenesis

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Journal of Integrative Plant Biology 2009年第8期51卷 792-799页

作者： yu-Qing He yan Wu Key Laboratory of Ministry of Education for Plant Developmental Biology College of Life Science Wuhan University Wuhan 430072 China

Although the oil body is known to be an important membrane enclosed compartment for oil storage in seeds, we have little understanding about its biogenesis during embryogenesis. In the present study we investigated the oil body emergence and variations in Brassica napus cv. Topas. The results demonstrate that the oil bodies could be detected already at the heart stage, at the same time as the embryos began to turn green, and the starch grains accumulated in the chloroplast stroma. In comparison, we have studied the development of oil bodies between Arabidopsis thaliana wild type （Col） and the low-seed-oil mutant wrinkled1-3. We observed that the oil body development in the embryos of Col is similar to that of B. napus cv. Topas, and that the size of the oil bodies was obviously smaller in the embryos of wrinkled1-3. Our results suggest that the oil body biogenesis might be coupled with the embryo chloroplast.

关键词： Arabidopsis thaliana Brassica napus chloroplast embryogenesis oil body

MoS2 embedded in 3D interconnected carbon nanofiber film as a free-standing anode for sodium-ion batteries

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Nano Research 2018年第7期11卷 3844-3853页

作者： Hai yang Min Wang Xiaowu Liu yu Jiang yan yu CAS Key Laboratory of Materials for Energy Conversion Department of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China

As a typical two-dimensional transition metal dichalcogenide, molybdenum disulfide （MoS2） is considered a potential anode material for sodium-ion batteries （NIBs）, due to its relatively high theoretical capacity （~ 670 mAh·g--1）. However, the low electrical conductivity of MoS2 and its dramatic volume change during charge/discharge lead to severe capacity degradation and poor cycling stability. In this work, we developed a facile, scalable, and effective synthesis method to embed nanosized MoS2 into a thin film of three-dimensional （3D）-interconnected carbon nanofibers （CNFs）, producing a MoS2/CNFs film. The free-standing MoS2/CNFs thin film can be used as anode for NIBs without additional binders or carbon black. The MoS2/CNFs electrode exhibits a high reversible capacity of 260 mAh·g^-1, with an extremely low capacity loss of 0.05 mAh·g^-1 per cycle after 2,600 cycles at a current density of 1 A·g^-1. This enhanced sodium storage performance is attributed to the synergistic effect and structural advantages achieved by embedding MoS2 in the 3D-interconnected carbon matrix.

关键词： MoS2 sodium ion batter flexible electrode three-dimensional (3D)interconnected carbon nanofiber

Recent progress in Li-S and Li-Se batteries

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Rare Metals 2017年第5期36卷 339-364页

作者： Lin-Chao Zeng Wei-Han Li yu Jiang yan yu Chinese Academy of Sciences Key Laboratory of Materials for Energy Conversion Department of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Li–S and Li–Se batteries have attracted tremendous attention during the past several decades, as the energy density of Li–S and Li–Se batteries is high（several times higher than that of traditional Li-ion batteries）.Besides, Li–S and Li–Se batteries are low cost and environmental benign. However, the commercial applications of Li–S and Li–Se batteries are hindered by the dissolution and shuttle phenomena of polysulfide（polyselenium）, the low conductivity of S（Se）, etc. To overcome these drawbacks, scientists have come up with various methods, such as optimizing the electrolyte, synthesizing composite electrode of S/polymer, S/carbon, S/metal organic framework（MOF） and constructing novelty structure of *** this review, we present a systematic introduction about the recent progress of Li–S and Li–Se batteries, especially in the area of electrode materials, both of cathode material and anode material for Li–S and Li–Se batteries. In addition, other methods to lead a high-performance Li–S and Li–Se batteries are also briefly summarized, such as constructing novelty battery structure, adopting proper charge–discharge conditions, heteroatom doping into sulfur molecules, using different kinds of electrolytes and binders. In the end of the review, the developed directions of Li–S and Li–Se batteries are also pointed out. We believe that combining proper porous carbon matrix and heteroatom doping may further improve the electrochemical performance of Li–S and Li–Se batteries. We also believe that Li–S and Li–Se batteries will get more exciting results and have promising future by the effort of battery community.

关键词： Li–S and Li–Se batteries Low cost Novelty battery structure Porous carbon matrix Heteroatom doping

Magnetism induced by Mn atom doping in SnO monolayer

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Chinese Physics B 2018年第11期27卷 581-585页

作者： Ruilin Han yu yan College of Physics and Electronic Engineering Shanxi UniversityTaiyuan 030006China Key Laboratory of Physics and Technology for Advanced Batteries(Ministry of Education) Department of PhysicsJilin UniversityChangchun 130012China

The structural,magnetic properties,and mechanism of magnetization of SnO monolayer doped with 3 d transition metal Mn atom were studied using first-principles *** calculated results show that the substitution doping is easier to realize under the condition of oxygen *** results reveal that the spin-splitting defect state of the Mn doped system is produced in the band gap and the magnetic moment of 5.0μB is *** induced magnetic moment by Mnsubis mostly derived from the 3 d orbital of the doped Mn *** magnetic coupling between magnetic moments caused by two Mn atoms in SnO monolayer is a long-range ferromagnetic,which is due to the hole-mediated p–p and p–d *** calculated results suggest that room-temperature ferromagnetism in a SnO monolayer can be induced after substitutional doping of a Mn atom.

关键词： SnO monolayer ferromagnetism first-principles doping