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Smart ionic liquid/water mixture system with dual stimuli-response to temperature and CO_(2)

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Nano Research 2023年第3期16卷 4152-4159页

作者： Xiaoqing Yuan ju.Liu Jingyu Qin Weili ma Guangyong Liu Yanlei Wang Hongyan He Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex SystemsCAS Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Green manufacture Chinese Academy of SciencesBeijing 100190China

Stimuli-responsive materials have important applications in chemistry and chemical ***,we synthesized five different polyetheramine-fatty acids(PEFA)ionic liquids(ILs),possessing the dual stimuli-responsive ability to temperature and CO_(2).These PEFA ILs have reversible lower critical solution temperature(LCST)phase behavior over a wide temperature range of 37-91℃,and reversible heterogeneous-homogeneous phase transition towards the addition and removal of CO_(2).Furthermore,the droplet size of the IL-water mixture system increased from 6.5 to 21.0 nm as the temperature increased from 25 to 56℃,and then recovered to 6.5 nm when the temperature decreased to 25℃.The addition and removal of CO_(2)also reversibly modulated the droplet size of the *** from nuclear magnetic resonance(NMR)and Fourier transform infrared(FTIR)spectra further showed that the temperature-dependent conformation of polyether amine chain in the cation dominates the temperature response,while the reversible formation of bicarbonate and fatty acids(FA)from CO_(2)and anion controls the CO_(2)-based reversible phase *** simulations revealed a microscopic response mechanism of the IL-water system to temperature and CO_(2),and a synergistic effect between the dual stimuli of temperature and CO_(2).These findings may provide a basis for the rational design and understanding of ILs-based stimuli-responsive materials and nanoreactors.

关键词： stimuli-responsive ionic liquids phase transitions temperature CO_(2)

Energy Band Structure of the Electron Gas in Periodic Quantum Wells

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Chinese Physics Letters 2012年第8期29卷 221-224页

作者： maO Sheng-Hong ma Yu-Ting XUE ju.Kui Key Laboratory of Atomic&Molecular Physics and Functional materials of Gansu Province College of Physics and Electronics EngineeringNorthwest Normal UniversityLanzhou 730070

The energy band structure and current density of electron gas with an exchange-correlation effect in periodic quantum wells are *** is found that the energy band shows a swallowtail structure at the boundary of the first Brillouin zone when the electron exchange-correlation effect is presented and the average electron density is smaller than a critical *** energy band structure is closely related to the current density of the system.

关键词： value exchange structure

Groundwater Evolution and its Influenceon the Fragile Ecology in the South Edge of Tarim Basin

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中国沙漠 2000年第2期20卷 44-48页

作者： ma Jinzhu Qian ju.Gao Qianzhao 兰州大学甘肃兰州 73 0 0 0 0 中科院寒区与旱区环境与工程所甘肃兰州 73 0 0 0 0

塔里木盆地南缘第四系松散沉积物以第三系弱透水层为隔水底板构成良好的储水场所 ,含水层厚 2 0 0～90 0 m,主要由冲洪积卵砾石、砂砾石和细砂组成。地下水位埋深由山前倾斜平原的 5 0～ 10 0 m逐渐过渡为细土平原的 1～ 3m,矿化度相应... 详细信息

塔里木盆地南缘第四系松散沉积物以第三系弱透水层为隔水底板构成良好的储水场所 ,含水层厚 2 0 0～90 0 m,主要由冲洪积卵砾石、砂砾石和细砂组成。地下水位埋深由山前倾斜平原的 5 0～ 10 0 m逐渐过渡为细土平原的 1～ 3m,矿化度相应地由 1～ 3g· L- 1 变化到 3～ 5 g· L- 1 。大部分地下水由地表径流和渠系、田间灌溉水入渗转化而成 ,约占地下水补给总量的 94%以上。人类历史时期 ,气候在地下水演变中依旧起着主导作用。随着人类社会文明的进步 ,人类活动对水资源系统的影响在环境变迁中表现出越来越显著的作用。 195 0— 1995年的 46 a中 ,塔里木盆地南缘地下水的开发利用比较有限 ,仅占 2 .3%左右 ,但地下水补给量减少了 2 6 .2 % ,与此同时 ,地下水位下降了 3～ 5 m,泉水递减了 2 8.7%。适于荒漠植物生长的地下水位埋深为 3～ 4m,高于此埋深将引起土壤盐渍化 ,低于此埋深植被会衰退进而导致土地沙漠化。因此 ,在开发利用水资源促进区域经济发展的同时 ,要重视地下水的保护和环境的改善。

关键词：地下水脆弱生态水资源开发塔里木盆地

Source Apportionment Research of Fine Particulate matter in the Atmosphere by PAHs

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Chemical Research in Chinese Universities 2016年第5期32卷 746-753页

作者： WANG ju.YANG Le ma Tianyi SUN Liyuan YU Liangui FANG Chunsheng Environmental Science Department College of Environment and Resources Jilin University Changchun 130012 P. R. China Key Laboratory of Groundwater Resources and Environment Ministry of EducationCollege of Environment and Resources Jilin University Changchun 130021 P. R. China College of Environmental Science and Engineering of Tong/i University Shanghai 200092 P. R. China Changchun Central Environmental Monitoring Station Changchun 130011 P. R. China

Haze weather frequently occurs in many cities in China. Polycyclic aromatic hydrocarbons（PAHs） in fine particulate matter（PM：.5） can adversely affect the environment and human health. In this paper, PM2.5 samples were collected at nine sites in a city in northeastern China from September 2013 to October 2014. Sixteen USEPA（US Evironment Protection Agency） priority PAHs in PM2.5 were analyzed to determine their spatial and temporal distri- bution characteristics. The source apportionment of PAHs was conducted with the Positive matrix Factorization（PMF） model. The results indicate that the concentrations of total PAHs（T-PAHs） in PM2.5 are within the range of 0.26 to 72.48 ng/m3. The seasonal variation of T-PAHs is winter〉spring〉autumn〉summer, and the space distribution of PAHs is JZP〉DP〉BFH〉LP〉EESA〉IPT〉CP〉HZMC〉JYP. In all types of PAils, three-ring and five-ring PAHs are signifi- cantly prominent（62%） in the heating period due to petrogenic sources and traffic emissions. Middle- and high-ring PAHs in the non-heating period are caused by coal combustion and vehicle exhaust, which accounts for 77% of the total emissions. The source apportionment results obtained by the diagnostic ratio of PAHs reflect that coal burning, traffic and other sources have a distinct influence on PAH emissions in this city. Six factors are defined by PMF v5.0, namely, coke oven emissions（7.7%）, biomass burning（44.3%）, petrogenic sources（10.7%）, coal combustion（10.4%）, gasoline engine emissions（16.7%）, and diesel engine emissions（10.3%）. The results indicate that the PAHs in PM2.5 in the city are primarily caused by combustion processes and vehicle exhaust.

关键词： Polycyclic aromatic hydrocarbon(PAH) Pollution characteristics Diagnostic ratio Positive matrix Factorization(PMF)

Microstructural evolution of carbon fiber reinforced SiC-based matrix composites during laser ablation process

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Journal of materials Science & Technology 2019年第12期35卷 2919-2925页

作者： Xiaolin Dang Xiaowei Yin Xiaomeng Fan Yuzhao ma Jiangtao Wang Panfei ju.Hongwei Song Science and Technology on Thermostructural Composite materials Laboratory Northwestern Polytechnical UniversityXi'an 710072China Key Laboratory for Mechanics in Fluid-Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China

In this work, four different carbon fiber reinforced SiC-based matrix composites(C/SiC) were prepared,and microstructure evolution during laser ablation process was characterized. Laser irradiation provided a special high-temperature environment up to 3500℃. For all four composites, different morphologies can be obtained in the transition region due to the oxidation of different matrices. While only needle-shaped carbon fiber and nanolayered carbon without any matrix remained in the central region, indicating that graphitization process occurred in the center, resulting from the high-temperature and low-oxygen environment in the laser process. Therefore, the laser ablation of C/SiC composites is controlled by chemical and physical erosion, and mainly by the physical erosion in the center.

关键词： Ablation performance C/SiC composite Laser ablation Mechanism

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Technical innovation in the “Beishan No. 1” hard rock tunnel boring machine for high-gradient spiral tunnels

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Frontiers of Engineering management 2024年第1期11卷 175-179页

作者： ju.WANG Mengxue QI Bin LONG Hongsu ma Beijing Research Institute of Uranium Geology Beijing 100029China China Railway 18th Bureau Group Tunnel Engineering Co. Ltd.Chongqing 400700China China Railway Construction Heavy Industry Co. Ltd.Changsha 410100China

1 Project overview The“Beishan No.1”,the world’s first-ever hard rock Tunnel Boring machine(TBM)tailored for high-gradient spiral tunnels,constitutes a pivotal element within the Beishan Underground Research Laboratory(URL)initiative in *** URL,the first URL for geological disposal of high level radioactive waste(HLW)in China,is a national key construction project listed in the“13th Five-Year Plan”.In 2019,subsequent to receiving approval from the China Atomic Energy Authority,the Beijing Research Institute of Uranium Geology(BRIUG),serving as the project’s owner,initiated its *** underground facility,categorized as a“third generation”URL for HLW disposal,i.e.,area-specific URL,was located in Beishan,Jiuquan City,Gansu Province,China,following more than three decades of rigorous research on site selection.

关键词： tunnel boring machine extremely hard rock continuous small-radius curves high gradient equipment technology innovation

The decrease of salinity in lakes on the Tibetan Plateau between 2000 and 2019 based on remote sensing model inversions

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International Journal of Digital Earth 2023年第1期16卷 2644-2659页

作者： Chong Liu Liping Zhu ju.bo Wang Jianting ju.Qingfeng ma Qiangqiang Kou State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijingPeople’s Republic of China Piesat Information Technology Co. Ltd.BeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China

Salinity is an essential factor of lake water environments and aquatic *** is also sensitive to climatic changes and human activities based on concentration variations of solved ***,there are few consecutively temporal studies on lake salinity variations on the Tibetan Plateau because the harsh environmental conditions make it diffcult to carry out in-situ observations for several *** this *** constructed a remote sensing retrieval model for lake salinity based on 87 in-situ lake investigations;moreover,interannual lake salinity and associated variations from 152 lakes larger than 50 km2 were analyzed on the Tibetan Plateau.A significant decreasing trend in lake salinity was observed between 2000 and 2019(pmanagement efficacy of water resources.

关键词： Optical remote sensing Tibetan Plateau lakes climate change salinity

Derivation and validation of soil total and extractable cadmium criteria for safe vegetable production

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Journal of Integrative Agriculture 2023年第12期22卷 3792-3803页

作者： LI Li-ju. LI Kun JIANG Bao LI ju.mei ma Yi-bing Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Sichuan Academy of Forestry Sichuan 610081P.R.China National Urban Environmental Pollution Control Engineering Research Center Beijing Municipal Research Institute of Environmental ProtectionBeijing 100037P.R.China National Observation and Research Station of Coastal Ecological Environments in macao/macao Environmental Research Institute Macao University of Science and TechnologyMacao SAR 999078P.R.China

Determining the appropriate soil cadmium(Cd)criteria for vegetable production is important for ensuring that the Cd concentrations of the vegetables meet food safety *** soil extractable Cd criteria for vegetable production are also essential for both food safety and environmental management,especially in areas with a high natural background *** the present study,soil total and extractable Cd criteria were derived using the approach of species sensitivity distribution integrated with soil aging and bioavailability as affected by soil properties.A dataset of 90 vegetable species planted in different soils was compiled by screening the published in literature in five bibliographic databases using designated search *** empirical soil-plant transfer model was applied to normalize the bioaccumulation *** normalization,the intra-species variability was reduced by 18.3 to 84.4%.The soil Cd concentration that would protect 95%(HC_(5))of the species was estimated by species sensitivity distribution curves that were fitted by the Burr III *** soil Cd criteria derived from the added approach for risk assessment were proposed as continuous criteria based on a combination of organic carbon and pH in the *** for total Cd and EDTA-extractable Cd in the soil ranged from 0.23 to 0.61 mg kg^(-1)and from 0.09 to 0.25 mg kg^(-1),*** experimental data were used to validate the applicability and validity of these *** of the predicted HC5 values in the field experimental sites were below the 1:1 *** results provide a scientific basis for soil Cd criteria for vegetable production that will ensure food safety.

关键词： Cd vegetables soil criteria species sensitivity distribution soil extractable Cd criteria

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Theoretical Studies on Intermolecular Interactions of 4-Amino-5-nitro-1,2,3-triazole Dimers

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Chinese Journal of Structural Chemistry 2006年第8期25卷 1004-1010页

作者： LU Ya-Lin GONG Xue-Dong ju.Xue-Hai ma Xiu-Fang XIAO He-Ming School of Chemical Engineering Nanjing Universityof Science and Technology Nanjing 210094 China

Seven optimized configurations and their electronic structures of 4-amino-5-nitro- 1,2,3-triazole dimers on their potential energy surface have been obtained by using density functional theory （DPT） method at the B3LYP/6-311＋＋G＊＊ level. The maximum intermolecular interaction energy is -35.42 kJ/mol via the basis set superposition error-correction （BSSE） and zero point energy-correction （ZPE）. Charge transfers between the two subsystems are small. The vibration analysis of optimized configurations was performed, and the thermodynamic property changes from monomer to dimer have been obtained with the temperature ranging from 200 to 800 K on the basis of statistical thermodynamics. It is found that the hydrogen bonds contribute to the dimers dominantly, and the extent of intermolecular interaction is mainly determined by the hydrogen bonds＇ strength rather than their number. The dimerization processes of Ⅳ, Ⅴand Ⅵ can occur spontaneously at 200 K.

关键词： 4-amino-5-nitro-1,2,3-triazole intermolecular interaction density functional theory thermodynamic properties

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