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Strategies for improving extraction capacity through preorganization structure:A novel 5,6-bicyclicmalonamide extractant(THPPD)

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Journal of Rare Earths 2024年第4期42卷 768-774页

作者： Miaomiao Zhang Zhen Yang Yuhua Cui Jianhui Su Heng Zhao Chengjin Xu Xiaolei Liu Guoxin Sun xiujing peng Yu Cui School of Chemistry and Chemical Engineering University of JinanJinan250022China Institute for Smart Materials&Engineering University of JinanJinan250022China Shandong Institute for Food and Drug Control Jinan250101China

Rational design of extractant structure to improve the extraction and separation capacity of rare earth elements(REEs)is a long-standing challenge.Herein,a new strategy was proposed to improve the stability of the chelating structure formed by malonamide and REEs.The stability of the chelating structure is greatly improved by using a double-ring framework structure which makes the two carbonyl groups of malonamide unable to rotate freely and both of them point to the metal ion position.Three benzyl groups were used to construct the hydrophobicity of the extractant and the organic shell of the extracted species.Tribenzylhexahydro-pyrrolo-pyridine-dione(THPPD)was designed and synthesized.The structure reduces the energy consumed by rotating carbonyl group in the coordination with metal ions and then improves the extraction ability of extractant.The crystal structure was preorganized as expected,with the two carbonyls pointing in a favorable coordination direction to the structural complement of the metal ion.The extraction behaviors of REEs with THPPD in a nitric acid medium were studied.Compared with N,N’-dibenzyl-N,N’-dimethylmalonamide(DBDM-MA)with a chain structure,the extraction capacity of THPPD is 360 times higher than that of DBDM-MA at 5.0 mol/L sodium nitrate.Furthermore,the binding energy and Gibbs free energy were investigated by density functional theory(DFT)in conjunction with the B3LYP.The theoretical results show that THPPD has more effective interaction with Pr(NO_(3))3 than DBDM-MA.The construction of chelating groups conformation is a worthy direction to improve the coordination ability and even selectivity of extractant.

关键词： Rare earth elements Extraction separation 5,6-bicyclicdiamide extractant

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Preparation of ultra-high pure scandium oxide with crude product from titanium white waste acid

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Journal of Rare Earths 2023年第5期41卷 764-770,I0005页

作者： xiujing peng Ling Li Miaomiao Zhang Yu Cui Xuchuan Jiang Guoxin Sun Institute for Smart Materials&Engineering University of JinanJinan 250022China School of Chemistry and Chemical Engineering University of JinanJinan 250022China

Recovery of scandium from titanium white waste acid is an essential source of scandium.Simple and economical production of high purity scandium remains a challenge.A new extractant,N,N,N’,N’-tetracyclohexyl-diglycolamide(TCHDGA),was synthesized,and the separation performance of scandium from impurity metal ions(Ti,Mn,Ba,Fe,Al and Mg)was investigated,The effects of mixing time,acid concentration and temperature on the scandium extraction were considered.The extraction mechanism was studied by infrared spectroscopy and the Equimole Series Method.Under optimized conditions,the extractant shows a strong affinity to scandium in the nitric acid medium and high extraction separation factors between scandium and these impurity metal ions,A process for the purification of scandium was established.The crude product obtained from titanium white waste acid,95%purity scandium oxide,can be purified to 99.99%after only one step of extraction,scrubbing,and stripping:This technology is economical and straightforward and can realize the high-value recovery of scandium in the titanium white waste acid.

关键词： TCHDGA Recovery Scandium Ultra-high pure Titanium white waste acid Rare earths

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Theoretical elucidation of rare earth extraction and separation by diglycolamides from crystal structures and DFT simulations

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Journal of Rare Earths 2021年第7期39卷 858-865,I0004页

作者： xiujing peng Jianhui Su Hao Li Yu Cui Jin Yong Lee Guoxin Sun Institute for Smart Materials&Engineering School of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China Department of Chemistry Sungkyunkwan UniversitySuwon 16419Republic of Korea

Diglycolamides(DGAs) show excellent application prospects for the extraction and separation of rare earth metals from highly radioactive liquid wastes and rare earth ores.The extraction ability of DGAs for rare earth ions in nitrate or chloride media increases with increasing atomic number of the rare earth metal.To understand the origin of this phenomenon,three binuclear crystals [Ln(TEDGA)_(3)][Ln(NO_(3))_(6)] of N,N,N’,N’-tetraethyldiglycolamide(TEDGA) with rare earth ions La(Ⅲ),Pr(Ⅲ) and Eu(III) were prepared and characterized crystallographically.The three complexes belong to the triclinic crystal system,P-1 space group.The bond lengths of Ln-O_(amide) are significantly shorter than those of Ln-O_(ether) in the same crystal.The Ln-O_(amide) and Ln-O_(enher) bond lengths gradually decrease with increasing atomic number of the rare earth ion.The dihedral angle formed by TEDGA and metal ions through the tridentate coordination gradually increases with increasing metal ion atomic number,tending toward the formation of sizeable planar coordination structures for the most massive rare earth ions.The structures of the compounds formed by the extractant and metal ion were optimized by means of DFT simulations.We find that the interaction between TEDGA and the rare earth ion is dominated by electrostatic interaction by analyzing binding energy,WBIs,Mulliken charge,natural electron configurations,and molecular orbital interaction.The covalent component of the Ln-O bonds of the complexes increases with increasing metal atomic number.The observed increase in extraction and separation capacity of diglycolamides for rare earth ions with increasing atomic number might be due to the formation of two fivemember rings by one tridentate ligand.The rare earth ions with large atomic numbers tend to form planar structures with large dihedral angles with DGA ligands.

关键词： Diglycolamide Extraction Separation Rare earth Crystal structures DFT simulations

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Subdaily to Seasonal Change of Surface Energy and Water Flux of the Haihe River Basin in China: Noah and Noah-MP Assessment

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Advances in Atmospheric Sciences 2019年第1期36卷 79-92页

作者： Fuqiang YANG Li DAN Jing peng xiujing YANG Yueyue LI Dongdong GAO Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences School of Atmospheric Sciences Chengdu University of Information Technology

The land surface processes of the Noah-MP and Noah models are evaluated over four typical landscapes in the Haihe River Basin(HRB) using in-situ observations. The simulated soil temperature and moisture in the two land surface models(LSMs) is consistent with the observation, especially in the rainy season. The models reproduce the mean values and seasonality of the energy fluxes of the croplands, despite the obvious underestimated total evaporation. Noah shows the lower deep soil temperature. The net radiation is well simulated for the diurnal time scale. The daytime latent heat fluxes are always underestimated, while the sensible heat fluxes are overestimated to some degree. Compared with Noah, Noah-MP has improved daily average soil heat flux with diurnal variations. Generally, Noah-MP performs fairly well for different landscapes of the HRB. The simulated cold bias in soil temperature is possibly linked with the parameterized partition of the energy into surface fluxes. Thus, further improvement of these LSMs remains a major challenge.

关键词：表面过程水流动精力季节土壤温度中国评价表面模型

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Spatiotemporal variations of carbon flux and nitrogen deposition flux linked with climate change at the centennial scale in China

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Science China Earth Sciences 2020年第5期63卷 731-748页

作者： Dongdong GAO Li DAN Guangzhou FAN Hanqin TIAN Jing peng xiujing YANG Fuqiang YANG Yueyue LI Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Atmospheric Science Chengdu University of Information EngineeringChengdu 610225China International Center for Climate and Global Change Research Auburn UniversityAL 36849USA Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The spatial and temporal variations of the vegetation carbon flux in China from 1901 to 2005 were studied using the vegetation net primary production(NPP)values from seven Earth-system models.In addition,the temporal and spatial changes in the nitrogen deposition flux in China were studied using the NHx and NOy fluxes from 1901 to 2005.The relationship between changes in the carbon flux,nitrogen flux and climate was analyzed.The results show that(1)over the past 100 years,NPP in China has shown an upward trend.The average trend coefficient is 0.88 and the NPP distribution trend is generally low in the north and high in the south,with a gradual increase from the northwest to the southeast.Temperature,precipitation and radiation are all conducive to plant growth in the direction of the gradient.The correlation coefficients between the ensemble model mean NPP and temperature,precipitation,longwave radiation and shortwave radiation are 0.88,0.73,0.91 and 0.67,respectively.(2)In the past 100 years,the NHx and NOy fluxes in China have shown an upward trend,with trend coefficients of 0.98 and 0.98,respectively,which pass the 99.9%confidence level of the t-test.NHx and NOy fluxes are also generally low in the north and high in the south,with a gradual increase from the northwest to the southeast in a step-like pattern.(3)The spatial distribution of the correlation coefficients between the NHx and NOy fluxes and air temperature is similar,with only slight differences in values.The spatial distribution of the correlation coefficients between the NHx and NOy fluxes and precipitation is similar in overall pattern,but the pattern is relatively complicated,with a positive-negative-positive-negative-positive pattern occurring across the monsoon region from north to south,and a negative-positive-negative-positive pattern occurring beyond the monsoon region from east to west.(4)The spatial distribution of the correlation coefficients between the NHx and NOy fluxes and NPP shows a generally consistent pattern,but the pattern is re

关键词： Net primary production(NPP) Temperature Precipitation NHx NOy

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Response of Growing Season Gross Primary Production to El Nino in Different Phases of the Pacific Decadal Oscillation over Eastern China Based on Bayesian Model Averaging

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Advances in Atmospheric Sciences 2021年第9期38卷 1580-1595页

作者： Yueyue LI Li DAN Jing peng Junbang WANG Fuqiang YANG Dongdong GAO xiujing YANG Qiang YU Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of ScienceBeijing 100049China Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China National Ecosystem Science Data Center Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityShaanxi 712100China School of Life Sciences University of Technology SydneySydney 2007NSWAustralia

Gross primary production(GPP) plays a crucial part in the carbon cycle of terrestrial ecosystems.A set of validated monthly GPP data from 1957 to 2010 in 0.5°× 0.5° grids of China was weighted from the Multi-scale Terrestrial Model Intercomparison Project using Bayesian model averaging(BMA).The spatial anomalies of detrended BMA GPP during the growing seasons of typical El Nino years indicated that GPP response to El Nino varies with Pacific Decadal Oscillation(PDO) phases: when the PDO was in the cool phase,it was likely that GPP was greater in northern China(32°–38°N,111°–122°E) and less in the Yangtze River valley(28°–32°N,111°–122°E);in contrast,when PDO was in the warm phase,the GPP anomalies were usually reversed in these two regions.The consistent spatiotemporal pattern and high partial correlation revealed that rainfall dominated this phenomenon.The previously published findings on how El Nino during different phases of PDO affecting rainfall in eastern China make the statistical relationship between GPP and El Nino in this study theoretically credible.This paper not only introduces an effective way to use BMA in grids that have mixed plant function types,but also makes it possible to evaluate the carbon cycle in eastern China based on the prediction of El Nino and PDO.

关键词： East China Bayesian model averaging Gross primary production El Nino Pacific Decadal Oscillation Monsoon rainfall

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陆面模式中氮循环过程的引入2:中国碳氮通量基线数据与变化特征

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Atmospheric and Oceanic Science Letters 2020年第6期13卷 518-526页

作者： DAN Li YANG xiujing YANG Fuqiang peng Jing LI Yueyue GAO Dongdong JI Jinjun HUANG Mei Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina

在陆面模式AVIM中模拟了1979-2015年中国碳氮通量的时空特征,碳通量GPP和NPP的模拟优于MODIS和TRENDY资料的结果。与CMIP6和CABLE模式的结果相比,AVIM对氮沉降和生物固氮模拟效果良好,在中国南部地区大于4 g N m^-2yr^-1。模拟GPP和NPP... 详细信息

在陆面模式AVIM中模拟了1979-2015年中国碳氮通量的时空特征,碳通量GPP和NPP的模拟优于MODIS和TRENDY资料的结果。与CMIP6和CABLE模式的结果相比,AVIM对氮沉降和生物固氮模拟效果良好,在中国南部地区大于4 g N m^-2yr^-1。模拟GPP和NPP在中国南方地区变化可达300和200 g C m^-2yr^-1,这与MODIS和TRENDY结果有差异,反映了季风区碳氮耦合的难度和必要性。中国南部氮沉降和生物固氮标准差可达0.8-1.2 g N m^-2yr^-1,距平和标准差评估是减小碳氮通量模拟偏差的关键。

关键词： AVIM 氮循环动力学区域尺度碳氮通量

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陆面模式中氮循环过程的引入Ⅰ:模式介绍及站点验证（英文）

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Atmospheric and Oceanic Science Letters 2019年第1期12卷 50-57页

作者： YANG xiujing DAN Li YANG Fuqiang peng Jing LI Yueyue GAO Dongdong JI Jinjun HUANG Mei Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences School of Atmospheric Sciences Chengdu University of Information and Technology Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

陆地生态系统氮循环对碳循环过程及其对气候变化的反馈具有重要的影响,但当前陆面模式多数都没有考虑氮循环过程对碳循环过程的限制。本研究基于氮在土壤-植被-大气中的传输交换过程,将氮循环过程引入到陆面模式AVIM(Atmosphere-Vegetat... 详细信息

陆地生态系统氮循环对碳循环过程及其对气候变化的反馈具有重要的影响,但当前陆面模式多数都没有考虑氮循环过程对碳循环过程的限制。本研究基于氮在土壤-植被-大气中的传输交换过程,将氮循环过程引入到陆面模式AVIM(Atmosphere-Vegetation Interaction Model)中,发展形成包含碳氮耦合过程的新版模式AVIM-CN。与2004-05年当雄生态系统定位站通量观测数据相对比,模式中引入氮循环过程后,高寒草甸的总初级生产力模拟值从1.1403 gC m^(-2)d^(-1)降到了0.7073 gC m^(-2)d^(-1),前者更接近通量站的观测值0.5407 gC m^(-2)d^(-1)。生态系统呼吸的模拟值也从1.7695 gC m^(-2)d^(-1)降到了1.0572 gC m^(-2)d^(-1),更接近对应的通量观测值0.8034 gC m^(-2)d^(-1)。整体而言,在模式中考虑氮的限制作用后,当雄站的热量通量和碳通量的模拟值更接近实测值。不考虑氮过程对碳过程的限制,模式高估了约40%的陆地生态系统碳通量。

关键词：碳氮耦合氮限制陆面模式碳-氮-水循环

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三维成像装置在结肠镜检查中的可行性研究

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中华消化内镜杂志 2023年第3期40卷 196-200页

作者：马宗慧张倩邢洁李鹏张澍田孙秀静首都医科大学附属北京友谊医院消化内科、国家消化系统疾病临床医学研究中心、北京市消化疾病中心、首都医科大学消化病学系、消化疾病癌前病变北京市重点实验室北京100050

目的评估三维成像装置在结肠镜检查中的初步应用。方法纳入2019年11—12月于首都医科大学附属北京友谊医院行无痛结肠镜检查的患者共60例,每例患者先后进行两次结肠镜检查,按照随机码分为2组,其中30例患者纳入试验组(进镜均使用二维结肠... 详细信息

目的评估三维成像装置在结肠镜检查中的初步应用。方法纳入2019年11—12月于首都医科大学附属北京友谊医院行无痛结肠镜检查的患者共60例,每例患者先后进行两次结肠镜检查,按照随机码分为2组,其中30例患者纳入试验组(进镜均使用二维结肠镜,首次退镜使用三维结肠镜,再次退镜使用二维结肠镜),30例患者纳入对照组(进镜均使用二维结肠镜,首次退镜使用二维结肠镜,再次退镜使用三维结肠镜),观察2组息肉检出情况,并进行退镜时间、操作体验、图像质量及并发症的评价。结果试验组首次息肉检出率为77.3%(17/22),高于对照组的43.5%(10/23),2组间差异有统计学意义(χ^(2)=5.351,P=0.021)。试验组10例操作者合并头晕症状,而对照组操作者无头晕症状(P=0.001)。2组首次结肠镜检查检出息肉直径[0.50(0.70)cm比0.30(0.20)cm,U=57.000,P=0.170]、退镜时间[(4.6±1.5)min比(5.2±1.9)min,t=-1.189,P=0.239]、图像质量(2组病变性质识别3分均为27例,腔道识别3分均为28例,P=1.000)差异无统计学意义。2组均无并发症发生。结论三维成像装置在结肠镜检查息肉检出中具有一定的优势,且具有可操作性,可应用于临床。

关键词：结肠镜检查成像,三维可行性研究安全性

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帽状息肉病临床和内镜特征及内镜下切除治疗效果

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中华消化内镜杂志 2022年第10期39卷 838-840页

作者：陈淑佳祁胜宾孙秀静李鹏张澍田首都医科大学附属北京友谊医院消化内科国家消化系统疾病临床研究中心北京市消化疾病中心北京100050 石家庄市人民医院消化内科石家庄050011

为了探讨帽状息肉病的临床、内镜特征,并评价其内镜下切除治疗效果,对2017年6月—2021年2月首都医科大学附属北京友谊医院行内镜黏膜下剥离术(endoscopic submucosal dissection,ESD)或内镜黏膜切除术(endoscopic mucosal resection,EMR... 详细信息

为了探讨帽状息肉病的临床、内镜特征,并评价其内镜下切除治疗效果,对2017年6月—2021年2月首都医科大学附属北京友谊医院行内镜黏膜下剥离术(endoscopic submucosal dissection,ESD)或内镜黏膜切除术(endoscopic mucosal resection,EMR)结直肠息肉切除治疗,经术后病理证实为帽状息肉病的14例病例(共56枚息肉)进行了回顾性分析。结果显示:男8例,女6例;年龄14岁~74岁,其中<60岁7例,≥60岁7例;7例(50.0%)伴消化道症状;息肉多发4例,单发10例(71.4%);息肉位于直肠42枚(75.0%),乙状结肠13枚(23.2%),横结肠1枚;山田分型Ⅰ型44枚(78.6%),Ⅱ型3枚,Ⅲ型5枚,Ⅳ型4枚;内镜下息肉表面可见明显白色帽状覆盖物41枚(73.2%)、明显充血发红23枚,其中两者均可见8枚;2例行ESD治疗、12例行EMR治疗,均完全切除,均未出现出血、穿孔、感染等并发症;7例伴消化道症状者术后临床症状均获得缓解;11例(78.6%)随访期间完成肠镜复查,均未见息肉复发。由此可见,帽状息肉病无性别、年龄发病差异,息肉多单发,直肠及乙状结肠多见,形态以山田Ⅰ型为主,表面多有白色帽状覆盖物,患者可无明显消化道症状,内镜下切除治疗安全、有效。

关键词：肠息肉帽状息肉病临床特征内镜特征内镜黏膜下剥离术内镜黏膜切除术

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