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Comparison of toxicity between lanthanum oxide nanoparticles and lanthanum chloride

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Journal of Rare Earths 2024年第2期42卷 424-430,I0007页

作者： Kun Huang Songchang Lai Miao guo xingwu Zhu Jiashuangwei Yuan Zhehao Liu Gonghua Hu Yanfang Gao School of Public Health and Health Management Gannan Medical UniversityGanzhou341000China

Due to the wide application of rare earth elements,lanthanum(La) is gradually accumulated in our living environment.Lanthanum can enter the body through a variety of routes,which has a series of effects on various systems.As a consequence,the safety of lanthanum deserves our attention.This study aims to compare the toxicity of lanthanum oxide nanoparticles(La_(2)O_(3) NPs) and lanthanum chloride(LaCl_(3)) and enrich the toxicity evaluation of lanthanum.Therefore,a 30 d intragastal experiment was conducted.C57BL/6j mice were given by La_(2)O_(3) NPs solution and LaCl_(3) solution respectively at doses of 0,30,60 and120 mg/kg BW(lanthanum content).The results show that,compared with the control group,both La_(2)O_(3)NPs and LaCl_(3) can reduce the body weight of female mice in the high-dose group,but for male mice,the high-dose La_(2)O_(3) NPs solution can increase the body weight,while LaCl_(3) has the opposite effect.The coefficients of liver,kidney,heart,lung,uterine and ovaries increase first and then decrease with the exposure dose,but testes and epididymides coefficient keep increasing with the exposure of LaCl_(3) and La_(2)O_(3) NPs.La_(2)O_(3) NPs and LaCl_(3) can reduce the concentration of triglycerides(TG) and increase the level of low density lipoprotein(LDL),but the effect of La_(2)O_(3) NPs is more obvious.La_(2)O_(3) NPs and LaCl_(3) can reduce the concentration of malondialdehyde(MDA),increase the total antioxidant capacity(T-AOC)and enhance the activity of catalase(CAT),but LaCl_(3) has more obvious protective effects on oxidative stress.La_(2)O_(3) NPs and LaCl_(3) have potential risks to liver,and the toxicity of La_(2)O_(3) NPs might be higher than that of LaCl_(3).

关键词： Rare earth elements Lanthanum oxide nanoparticles Lanthanum chloride Lipid metabolism Oxidative stress

Nutrient enrichment driven by canopy rainfall redistribution:Mechanism,quantification,and pattern

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Science China Earth Sciences 2024年第5期67卷 1529-1544页

作者： Chuan YUAN Xiaoping YUE Yafeng ZHANG Yu ZHANG Yanting HU Qiang TANG Li guo Shuai WANG xingwu DUAN Wenhua XIANG Xiaohua WEI Xiaoyan LI College of Forestry and Biotechnology Zhejiang A&F UniversityHangzhou 311300China Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station School of Geographical SciencesSouthwest UniversityChongqing 400715China Shapotou Desert Research and Experiment Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Geographical Sciences Hebei Normal UniversityShijiazhuang 050024China Faculty of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Institute of International Rivers and Eco-securityYunnan UniversityKunming 650091China Department of Earth Environmental and Geographic SciencesUniversity of British Columbia(Okanagan)KelownaBritish Columbia V1V 1V7Canada

Vegetation canopies intercept and redistribute rainfall into throughfall and stemflow,which transfer substantial amounts of elements into the soil,influencing soil microbial community,plant survival,and plant community succession.Despite advancements in ecohydrological research,the implication of nutrient enrichment resulting from this redistribution of rainfall by canopies remains largely unexplored.To address this gap,we conducted a systematic review of 1020 papers published between 2000 and 2022,gathering data on nutrient concentration and enrichment for critical ions(including K^(+),Na^(+),Ca^(2+),Mg^(2+),NH_(4)^(+),Cl^(-),NO_(3)^(-)and SO_(4)^(2-))from the Web of Science and Chinese Knowledge Infrastructure databases.We aimed to synthesize the mechanisms,quantify the enrichments,and identify global patterns of nutrient enrichment in stemflow and throughfall across climate zones,and vegetation types and ecosystems.The results of this study indicate that stemflow exhibits,on average,2.1times greater ion concentration(6.13 mg L^(-1))compared to throughfall.In particular,among the investigated ions,SO_(4)^(2-)(12.45and 6.32 mg L^(-1))for stemflow and throughfall,respectively,and Cl^(-)(9.21 and 4.81 mg L^(-1))exhibit the highest concentrations in both rainfall redistribution components,while K^(+)(13.7 and 5.8)and Mg^(2+)(5.6 and 2.8)have the highest enrichment factors.Across climate zones,throughfall and stemflow show the lowest ion concentrations but the highest enrichment factors in extremely humid regions.Along the temperature gradient,ion concentrations are the highest in cold climates with no clear patterns observed for enrichment factors with increasing temperature.In addition,shrubs,conifers,mixed forests,and artificial ecosystems demonstrate enrichment factors 1.1 to 3.0 times greater than those of trees,broad-leaved plants,pure forests,and natural ecosystems.These findings emphasize the need for increased attentions to artificial ecosystems,such as urban and agricultural ecosystems,which often received

关键词： Ecohydrology Rainfall redistribution Nutrients transport Enrichment characteristics Climate zones

Rainfall erosivity estimation over the Tibetan plateau based on high spatial-temporal resolution rainfall records

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International Soil and Water Conservation Research 2022年第3期10卷 422-432页

作者： Yueli Chen xingwu Duan guo Zhang Minghu Ding Shaojuan Lu State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijingChina Institute of International Rivers and Eco-security Yunnan UniversityKunmingChina CMA Earth System Modeling and Prediction Centre BeijingChina

The Tibetan Plateau(TP)in China has been experiencing severe water erosion because of climate warming.The rapid development of weather station network provides an opportunity to improve our understanding of rainfall erosivity in the TP.In this study,1-min precipitation data obtained from 1226 weather stations during 2018–2019 were used to estimate rainfall erosivity,and subsequently the spatial-temporal patterns of rainfall erosivity in the TP were identified.The mean annual erosive rainfall was 295 mm,which accounted for 53%of the annual rainfall.An average of 14 erosive events occurred yearly per weather station,with the erosive events in the wet season being more likely to extend beyond midnight.In these cases,the precipitation amounts of the erosive events were found to be higher than those of the daily precipitations,which may result in implicit bias as the daily precipitation data were used for estimating the rainfall erosivity.The mean annual rainfall erosivity in the TP was 528 MJ mm·ha^(-1)·h^(-1),with a broader range of 0–3402 MJ mm·ha^(-1)·h^(-1),indicating a significant spatial variability.Regions with the highest mean annual rainfall erosivity were located in the forest zones,followed by steppe and desert zones.Finally,the precipitation phase records obtained from 140 weather stations showed that snowfall events slightly impacted the accuracy of rainfall erosivity calculation,but attention should be paid to the erosion process of snowmelt in the inner part of the TP.These results can be used as the reference data for soil erosion prediction in normal precipitation years.

关键词： Erosive rain Rainfall erosivity Spatial-temporal patterns 1-Min precipitation data Tibetan Plateau

四川盆地德阳—安岳裂陷槽寒武系筇竹寺组超深层页岩气地质工程一体化高产井培育实践与勘探突破

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中国石油勘探 2024年第3期29卷 58-68页

作者：郑马嘉郭兴午伍亚赵文韬邓琪谢维扬欧志鹏中国石油西南油气田公司开发事业部中国石油西南油气田公司页岩气研究院中国石油西南油气田公司蜀南气矿

四川盆地德阳—安岳裂陷槽寒武系筇竹寺组超深层页岩储层地层时代老、埋藏深度大、热演化程度高,勘探开发难度大,国内外尚无可直接借鉴的经验。为此,基于地质工程一体化理念,探索建立筇竹寺组“部—钻—压—采”一体化高产井培育关键技... 详细信息

四川盆地德阳—安岳裂陷槽寒武系筇竹寺组超深层页岩储层地层时代老、埋藏深度大、热演化程度高,勘探开发难度大,国内外尚无可直接借鉴的经验。为此,基于地质工程一体化理念,探索建立筇竹寺组“部—钻—压—采”一体化高产井培育关键技术体系:(1)一体化井位部署,深化筇竹寺组“裂陷槽控藏”认识,明确优质储层分布模式,明确高产井实施技术界限,支撑井位优化部署;(2)一体化钻录定导,基于地质工程参数综合评价,优中选优确定靶体,优化井轨迹,强化地质钻井一体化精细管理,保障优质储层钻遇率;(3)一体化压裂增产,基于一体化压裂模型优化压裂设计,形成“促复杂+扩体积+强支撑+防套变”压裂工艺,有效实现裂缝均匀开启、高效扩展、全域支撑及储层改造体积最大化;(4)一体化精细返排,形成“四因子”返排增产技术,结合精细排采分析平台,实现降低储层伤害与气井增产“双突破”。基于上述技术体系,资201井首次在国内寒武系4500m以深的页岩储层测试获得高产工业气流,威页1H井成功实现高产井复制,初步落实埋深5000m以浅有利区面积近3000km2,资源量近2×10^(12)m^(3)。所形成的高产井培育技术和方法,为破解寒武系超深层页岩气规模效益开发难题奠定了坚实基础。

关键词：四川盆地寒武系筇竹寺组超深层页岩气地质工程一体化高产井培育

Novel approach for identifying Z-axis drift of RLG based on GA-SVR model

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Journal of Systems Engineering and Electronics 2014年第1期25卷 115-121页

作者： guo Wei Xudong Yu xingwu Long College of Optoelectric Science and Engineering National University of Defense Technology

This paper describes a novel approach for identifying the Z-axis drift of the ring laser gyroscope （RLG） based on ge-netic algorithm （GA） and support vector regression （SVR） in the single-axis rotation inertial navigation system （SRINS）. GA is used for selecting the optimal parameters of SVR. The latitude error and the temperature variation during the identification stage are adopted as inputs of GA-SVR. The navigation results show that the proposed GA-SVR model can reach an identification accuracy of 0.000 2 （？）/h for the Z-axis drift of RLG. Compared with the ra-dial basis function-neural network （RBF-NN） model, the GA-SVR model is more effective in identification of the Z-axis drift of RLG.

关键词： ring laser gyroscope （RLG） support vector regression （SVR） inertial navigation system （INS） genetic algo-rithm （GA）

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自动电位滴定法测定无糖饮料中的总酸含量

山东化工 2024年第5期53卷 132-134页

作者：郭玉楼柳樱华吴继强于娇娇苏兴武杜莹莹王小龙兰州石化职业技术大学甘肃兰州730060

基于自动电位滴定法分析测定了无糖饮料中的总酸含量,实验结果显示,当称取无糖气泡水50.0051 g、无糖茶饮品50.0227 g、无糖果汁50.0522 g时,其总酸含量分别为3.89,3.58,4.12 g/kg。该方法的加标回收率在94.0%~106.0%,RSD均小于2%,表明... 详细信息

基于自动电位滴定法分析测定了无糖饮料中的总酸含量,实验结果显示,当称取无糖气泡水50.0051 g、无糖茶饮品50.0227 g、无糖果汁50.0522 g时,其总酸含量分别为3.89,3.58,4.12 g/kg。该方法的加标回收率在94.0%~106.0%,RSD均小于2%,表明该方法准确度高、精密度好、可行性高。本文也简单探讨了测定过程中误差的来源及减免方法,其中误差主要来源于NaOH标准溶液的配制、无糖饮料待测试液的滴定分析及分析测试人员的操作。

关键词：无糖饮料总酸自动电位滴定法误差

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Oxygen vacancies enriched nickel cobalt based nanoflower cathodes: Mechanism and application of the enhanced energy storage

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Journal of Energy Chemistry 2021年第11期30卷 252-261,I0006页

作者： Jiahui Ye xingwu Zhai Long Chen Wen guo Tiantian Gu Yulin Shi Juan Hou Fei Han Yi Liu Changchun Fan Gang Wang Shanglong Peng Xuhong guo Key Laboratory for Green Process of Chemical Engineering of Xinjiang Bingtuan School of Chemistry and Chemical EngineeringShihezi UniversityShihezi 832003XinjiangChina Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology College of Materials Science and EngineeringHunan UniversityChangsha 410082HunanChina Institut für Chemie AG ElektrochemieTechnische Universität ChemnitzChemnitz 09111Germany National&Local Joint Engineering Laboratory for Optical Conversion Materials and Technology School of Physical Science and TechnologyLanzhou UniversityLanzhou 730000GansuChina State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China

The rational design of oxygen vacancies and electronic microstructures of electrode materials for energy storage devices still remains a challenge. Herein, we synthesize nickel cobalt-based oxides nanoflower arrays assembled with nanowires grown on Ni foam via the hydrothermal process followed annealing process in air and argon atmospheres respectively. It is found that the annealing atmosphere has a vital influence on the oxygen vacancies and electronic microstructures of resulting NiCo_(2)O_(4) (NCO-Air) and CoNiO_(2) (NCO-Ar) products, which NCO-Ar has more oxygen vacancies and larger specific surface area of 163.48 m^(2)/g. The density functional theory calculation reveals that more oxygen vacancies can provide more electrons to adsorb –OH free anions resulting in superior electrochemical energy storage performance. Therefore, the assembled asymmetric supercapacitor of NCO-Ar//active carbon delivers an excellent energy density of 112.52 Wh/kg at a power density of 558.73 W/kg and the fabricated NCO-Ar//Zn battery presents the specific capacity of 180.20 mAh/g and energy density of 308.14 Wh/kg. The experimental measurement and theoretical calculation not only provide a facile strategy to construct flower-like mesoporous architectures with massive oxygen vacancies, but also demonstrate that NCO-Ar is an ideal electrode material for the next generation of energy storage devices.

关键词： NiCo_(2)O_(4) CoNiO_(2) Supercapacitor Oxygen vacancy defects Flower-like microstructure

Advances in 3D Bioprinting

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Chinese Journal of Mechanical Engineering(Additive Manufacturing Frontiers) 2022年第1期1卷 1-15页

作者： Yongcong Fang Yuzhi guo Tiankun Liu Runze Xu Shuangshuang Mao xingwu Mo Ting Zhang Liliang Ouyang Zhuo Xiong Wei Sun Biomanufacturing Center Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Biomanufacturing and Rapid Forming Technology Key Laboratory of Beijing Beijing 100084China “Biomanufacturing and Engineering Living Systems”Innovation International Talents Base(111 Base) Beijing 100084China Department of Mechanical Engineering and Mechanics Drexel UniversityPhiladelphiaPA 19104USA

Three-dimensional(3D)bioprinting has emerged as a promising approach for engineering functional tissues and organs by layer-by-layer precise positioning of biological materials,living cells,and biochemical components.Compared with nonbiological printing,3D bioprinting involves additional complexities and technical challenges owing to the processing of living cells,such as the appropriate biomaterials that fulfill the requirements for both printability and functionality.In this review,we first introduce the development course of 3D bioprinting,highlighting innovative forms of living building blocks and advances in enabling techniques of 3D bioprinting.We then summarize the state-of-the-art advancements in 3D bioprinting for biomedical applications,including macroscale tissue or organ bioprinting,disease modeling,microphysiological systems,biobots,and bioprinting in space.Despite the rapid development of 3D bioprinting over the past decades,most 3D bioprinted tissue or organ constructs are still far from being suitable for clinical translation,and it is necessary for the field of bioprinting to shift its focus from shape mimicking towards functionality development.Therefore,we provide our perspectives on this burgeoning field with an emphasis on functional maturation post printing and translational applications at the bedside.

关键词： 3D bioprinting Tissue engineering Disease model Organ-on-a-chip Biohybrid robots Space bioprinting

New determination of the position of the pulsar B0329+54 with Chinese VLBI network

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Science China(Physics,Mechanics & Astronomy) 2010年第8期53卷 1559-1564页

作者： guo Li ZHENG xingwu ZHANG Bo WANG WeiHua ZHENG WeiMin SHU FengChun LI JinLing YU Yun HAO LongFei YUAN JianPing XIA Bo Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Department of Astronomy Nanjing UniversityNanjing 210093China Yunnan Astronomical Observatory National Astronomical ObservatoryChinese Academy of SciencesKunming 650011China Urumqi Astronomical Observatory National Astronom

We present the first successful CVN (Chinese VLBI Network) phase-referencing observation of the pulsar B0329+54 on October 16, 2008 in S band. A new background source, J0347+5557, 2.5° away from the pulsar was employed as a position reference, which is closer to the pulsar and better for the ‘nodding’ mode than that used in previous observations. The position by fitting image of the pulsar relative to the calibrator is accurately determined at the level of tens of μas, which is comparable with the present differential VLBI astrometric accuracy, proving that CVN will be a potential powerful tool for astrometry and astrophysics.

关键词： ical Observatory Chinese Academy of Sciences Urumqi 830011 China