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Characteristics of phytoliths in Leymus chinensis from different habitats on the Songnen Plain in Northeast China and their environmental implications

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Science China Earth Sciences 2010年第7期53卷 984-992页

作者： JIE DongMei liu ZhaoYang SHI LianXuan liu HongMei GE Yong College of Urban and Environmental Science Northeast Normal UniversityChangchun 130024China School of Life Sciences Northeast Normal UniversityChangchun 130024China

The characteristics of phytoliths in Leymus chinensis leaves from five different pH-value habitats from Songnen Plain in China were analyzed to reveal their environmental implications and possible use for quantitative reconstruction of the paleoenvironment. The phytoliths in leaves of L. chinensis from the five habitats showed a non-linear correlation with soil pH. The main types of phytoliths from the different habitats were exactly the same, including silicified stomata, hat-shaped, lanceolate, elongated, multilateral-plate, and tooth-shaped. However, there were significant differences in the contents of each shape of phytoliths among the five habitats. The amount and the volume of weakly tooth-shaped, lanceolate phytoliths and silicified stomata increased with increased pH, while the total amount of phytoliths was reduced. In addition, there were different types of phytoliths in the L. chinensis leaves from the five habitats of different pH, suggesting that the types of phytoliths were controlled, at least in part, by soil pH. The changes of size and percentage of phytoliths were most remarkable at pH 10.15–10.18, indicating that this is the highest pH value that L. chinensis can tolerate.

关键词： phytolith pH habitat Leymus chinensis Songnen Plain environmental implications

Identification of coexistence of biological and non-biological aerosol particles with DAPI (4′,6-diamidino-2-phenylindole) stain

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Particuology 2023年第1期72卷 49-57页

作者： Ting liu Jiaquan Zhang Junji Cao Han Zheng Changlin Zhan Hongxia liu Lili Zhang Kai Xiao Shan liu Dong Xiang Daizhou Zhang School of Environmental Science and Engineering Hubei Polytechnic UniversityHubei Key Laboratory of Mine Environmental Pollution Control and RemediationHuangshi 435003China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China School of Computer Science and Artificial Intelligence Wuhan University of TechnologyWuhan 430063China Faculty of Environmental and Symbiotic Sciences Prefectural University of KumamotoKumamoto 862-8502Japan

The fluorescent dye 4′,6-diamidino-2-phenylindole (DAPI) has been widely used to stain microorganisms in various environment media. We applied DAPI fluorescence enumeration to airborne microorganisms and found that non-biological particles, including organic compounds, minerals, and soot, were also visible upon exposure to UV excitation under fluorescence microscope. Using laboratory-prepared biological particles as the control, we investigated the feasibility of identifying both biological and non-biological particles in the same sample with DAPI staining. We prepared biological (bacterial, fungi, and plant detritus) and non-biological (biochar, soot, mineral, metal, fly ash, salt) particles in the laboratory and enumerated the particles and their mixture with DAPI. We found that mineral particles were transparent, and biochar, soot, metals and fly ash particles were black under a filter set at excitation 350/50 nm and emission 460/50 nm bandpass (DAPI-BP), while biological particles were blue, as expected. Particles of the water-soluble salts NaCl and (NH_(4))_(2)SO_(4) were yellow under a filter set at excitation 340–380 nm and emission 425 nm long pass (DAPI-LP). Case studies with samples of dustfall, atmospheric aerosols and surface soils could allow for the quantification of the relative number of different types of particles and particles with organic matter or salt coating as well. Fluorescence enumeration with DAPI stain is thus able to identify the co-existence of biological and non-biological particles in the air, at least to the extent of those examined in this study.

关键词： 4',6-diamidino-2-phenylindole(DAPI) Biological particles Nonbiological particles Atmospheric aerosols

Methylene green-mediated sensor highly sensitive to hydrogen peroxide based on entrapment of horseradish peroxidase in composite membrane of regenerated silk fibroin and poly(vinyl alcohol)

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Chinese Journal of Chemistry 1996年第4期14卷 359-366页

作者： Wu, YX liu, HY Qi, DY liu, YC Qian, JH liu, SH Yu, TY Deng, JQ SHANGHAI UNIV DEPT CHEM & CHEM ENGNSHANGHAI 200072PEOPLES R CHINA FUDAN UNIV DEPT MACROMOL SCI & CHEMSHANGHAI 200433PEOPLES R CHINA

A novel composite membrane of poly(vinyl alcohol) and regenerated silk fibroin was employed to immobilize horseradish peroxidase (HRP) and IR was used to give a useful insight into the structure of the composite membrane before and after ethanol treatment. A methylene green-mediated sensor sensitive to hydrogen peroxide was fabricated, based on the composite membrane as immobilization matrix for HRP. Cyclic voltammetry and amperometric measurement were for the first time utilized to demonstrate the suitability of methylene green as an electron transfer mediator between immobilized HRP and a glassy carbon electrode in bioelectrocatalytic reduction of hydrogen peroxide. Performance and characteristics of the sensor were evaluated in respect to response time, detection limit, applied potential and concentration of the mediator. The sensor possesses a variety of characteristics including good sensitivity, rapid response time and low detection of limit of 0.1 mu mol/L.

关键词： sensor poly(vinyl alcohol) regenerated silk fibroin methylene green horseradish peroxidase hydrogen peroxide

Surface Organometallic Chemistry for Single-site Catalysis and Single-atom Catalysis

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Chemical Research in Chinese Universities 2022年第5期38卷 1139-1145页

作者： WU Fan liu Pengxin School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210P.R.China

Although driven by different research interests,single-site catalysts and single-atom catalysts are both believed to be model systems bridging homogeneous and heterogeneous *** two concepts are similar but *** this review,we will first explain the difference between single-atom catalysis and single-site catalysis,in terms of their goals,synthetic methods and coordination structures of corresponding ***,we will introduce the surface organometallic chemistry method,a method traditionally used for synthesizing single-site *** will explain why it might benefit the single-atom catalysis *** last,the choice of support to accommodate the method for synthesizing single-atom catalysts will be discussed.

关键词： Surface organometallic chemistry Single-atom catalyst Single-site catalyst Atomically dispersed catalyst Surface coordination structure

Model assessment of nutrient removal via planting Sesuvium portulacastrum in floating beds in eutrophic marine waters:the case of aquaculture areas of Dongshan Bay

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Acta Oceanologica Sinica 2019年第12期38卷 91-100页

作者： Xuehai liu Xinming Pu Donglian Luo Jing Lu Zili liu First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Fujian Fishery Research Institute Xiamen 361012China Laboratory of Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Key Laboratory of Marine Science and Numerical Modeling Ministry of Natural ResourcesQingdao 266061China Key Laboratory of Science and Engineering for the Marine Ecological Environment Ministry of Natural ResourcesQingdao 266061China

Many coastal seas are severely eutrophic and required to reduce nutrient concentrations to meet a certain water quality *** proposed a method for nutrient removal by planting Sesuvium portulacastrum at the water surface using the floating beds in the aquaculture area of the Dongshan Bay as an example,which is an important net-cage culture base in China and where dissolved inorganic nitrogen(DIN)and dissolved inorganic phosphate(DIP)reach 0.75 mg/L and 0.097 mg/L,respectively far exceeding China’s Grade IV water quality *** simulations were taken using the ecological model,field observations and field plantation experimental results to assess the environmental restoration effects of planting *** at some certain spatial *** field experiments suggested that the herbs can absorb 377 g/m^2 nitrogen and 22.9 g/m^2 phosphorus in eight months with an inserting density of^60 shoot/m^*** numerical experiments show that the greater the plantation area is,the more nutrient *** in^12%of the study area could lower nutrients to the required Grade II standards,i.e.,0.2 mg/L

关键词： phytoremediaton Sesuvium portulacastrum ecological model nutrient removal

A disaggregation approach for estimating high spatial resolution broadband emissivity for bare soils from Landsat surface reflectance

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International Journal of Digital Earth 2018年第7期11卷 691-702页

作者： Jie Cheng Shunlin Liang Hao liu Aixiu Nie Qiang liu State Key Laboratory of Remote Sensing Science Faculty of GeographyBeijing Normal UniversityBeijingPeople’s Republic of China Department of Geographical Sciences University of MarylandCollege ParkMDUSA State Key Laboratory of Remote Sensing Science College of Global Change and Earth System ScienceBeijing Normal UniversityBeijingPeople’s Republic of China

High spatial resolution land surface broadband emissivity(BBE)is not only useful for surface energy balance studies at local scales,but also can bridge the gap between existing coarser resolution BBE products and point-based field *** study proposes a disaggregation approach that utilizes the established BBE–reflectance relationship for estimating high spatial resolution BBE for bare soils from Landsat surface reflectance *** disaggregated BBE is compared to the BBE calculated from spatial–temporal matched Advanced Spaceborne Thermal Emission and Reflectance Radiometer emissivity *** results show that better agreement is achieved over relative homogeneous areas,but deteriorated over heterogeneous and cloud-contaminated *** addition,field-measured emissivity data over large homogeneous desert were also used to validate the disaggregated BBE,and the bias is *** comparison and validation results indicated that the disaggregation approach can obtain high spatial resolution BBE with better accuracy for homogeneous area.

关键词： Broadband emissivity ASTER TM bare soil disaggregation

Continuous near-complete photocatalytic degradation of toluene by V/N-doped TiO_(2)loade d on honeycomb ceramics under UV irradiation

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Journal of Materials Science & Technology 2024年第7期174卷 188-194页

作者： Gang liu Lijuan Han Jingwei Wang Yongqiang Yang Zuoyan Chen Bilu liu Xingcai An Gansu Natural Energy Institute Lanzhou 730046China Shenzhen Geim Graphene Center Tsinghua-Berkeley Shenzhen Institute&Institute of Materials ResearchTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Photocatalytic degradation of volatile organic compounds(VOCs)is a significant applying aspect of *** the modulation of photocatalysts and the rational dispersion of them on supports are key for solar-driven VOC *** batch-type photoreactors have low efficiency while continuous-flow photoreactors suffer from the problem of incomplete removal of ***,aiming for continuous and complete degradation of toluene gas as the target contaminant,continuous-flow pho-tocatalytic degradation reactors were made by adhering the vanadium and nitrogen codoped TiO_(2)on honeycomb ceramics(V/N-TiO_(2)@HC)by a simple sol-gel *** such a reactor,the rich ordered pores in the HC accelerate mass transport of toluene,and the introduction of V/N dopants narrows the bandgap and widens the light absorption range of TiO_(2),together resulting in continuous and nearly-complete pho-tocatalytic degradation of *** unique and stable structure of HC allows the photocatalysts to be *** degradation rate of toluene gas can reach 97.8%,and after 24 rounds of photocatalytic degra-dation,there is still a degradation rate of 96.7%.The impacts of loading times and gaseous flow rate on the photocatalytic performance of V/N-TiO_(2)@HC are studied in *** study provides a practical so-lution for the continuous and complete photocatalytic degradation of VOCs and opens a new application field for HC.

关键词： Honeycomb ceramics V/N co-doped TiO_(2) Photocatalytic degradation Toluene gas Continuous and complete degradation

Vegetation Traits and Soil Properties in Response to Utilization Patterns of Grassland in Hulun Buir City, Inner Mongolia, China

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Chinese Geographical Science 2014年第4期24卷 471-478页

作者： liu Miao liu Guohua WU Xing WANG Hao CHEN Li State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sciences University of Chinese Academy of Sciences Monitoring Station for Eco-Environment of Hulun Buir

Numerous studies have focused on vegetation traits and soil properties in grassland, few of which concerned about effects of human utilization patterns on grassland yet. Thus, this study hypothesized that human disturbance(e.g., grazing, mowing and fencing) triggered significant variation of biomass partitioning and carbon reallocation. Besides, there existed some differences of species diversity and soil fertility. To address these hypotheses of grassland with diverse utilization patterns in Hulun Buir City, Inner Mongolia, China, we sampled in situ about aboveground biomass(AGB) and belowground biomass(BGB) to evaluate their biomass allocation. Species diversity and soil properties were also investigated. Subsequently, we discussed the relationship of species diversity with environmental conditions, using data collected from 23 sites during the ecological project period of Returning Grazing Lands to Grasslands(RGLG) program. The results were as follows: 1) both AGB and BGB were lower on grazing regime than those on fencing and mowing, but the ratio of root-to-shoot(R/S) was higher on grazing regime than the other two utilization patterns; 2) neither of evenness and Simpson Index was different significantly among all grassland utilization patterns in desert, typical, and meadow grassland at 0.05. In meadow grassland, species richness of fencing pattern was significantly higher than that of grazing pattern(p < 0.05); 3) both of soil organic carbon content and soil available phosphorous content were increased significantly on fencing pattern than grazing pattern(p < 0.05) in desert grassland, and mowing patterns increased the soil nutrients(soil organic carbon, soil total phosphorous, soil available phosphorous, and soil total nitrogen) significantly compared with grazing patterns(p < 0.05) in typical grassland. However, there were no significant differences among utilization patterns in meadow grassland. In conclusion, both of AGB and BGB were increased significantl

关键词： grassland utilization pattems biomass allocation species diversity soil properties temperate grassland Hulun Buir City

δ/γtransformation in non-equilibrium solidified peritectic Fe-Ni alloy

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Science China(Physics,Mechanics & Astronomy) 2007年第4期50卷 421-431页

作者： CHEN YuZeng liu Feng YANG GenCang liu Ning ZHOU YaoHe State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

Through phase transformation kinetic analysis and experimental observation,the δ/γtransformation occurring in the non-equilibrium peritectic Fe-4.33at.%Ni alloys was systematically *** to JMA solid-state transformation ki-netic theory,the Time-Temperature-Transformation(TTT)curves of the δ/γtrans-formation in peritectic Fe-Ni alloy were *** this basis,the physical cor-relation between the δ/γtransformation and the initial undercooling of melt(T)was *** results indicate that the change of T can alter not only the overall δ/γtransformation pathways but also the transformation fraction with re-spect to each transformation mechanism.

关键词： δ/γ transformation undercooling non-equilibrium solidification peritectic reaction Fe-Ni alloy