检索结果-南通市图书馆

Highly efficient P uptake by Fe3O4 loaded amorphous Zr-La (carbonate) oxides: Electrostatic attraction, inner-sphere complexation and oxygen vacancies acceleration effect

引用

Journal of environmental Sciences 2022年第10期34卷 18-29页

作者： Chenyang Liu Yili Wang Xiaolin Li Junyi Li Shuoxun Dong Haotian Hao Yao Tong Yanqing Zhou College of environmental Science and Engineering Beijing Key Lab for Source Control Technology of Water PollutionBeijing Forestry UniversityBeijing 100083China Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China Research Center for Eco-environmental Sciences Chinese Academy of SciencesBeijing 100085China

Bimetallic oxides composites have received an increasing attention as promising adsorbents for aqueous phosphate (P) removal in recent years. In this study, a novel magnetic composite MZLCO was prepared by hybridizing amorphous Zr-La (carbonate) oxides (ZLCO) with nano-FeOthrough a one-pot solvothermal method for efficient phosphate adsorption. Our optimum sample of MZLCO-45 exhibited a high Langmuir maximum adsorption capacity of 96.16 mg P/g and performed well even at low phosphate concentration. The phosphate adsorption kinetics by MZLCO-45 fitted well with the pseudo-second-order model, and the adsorption capacity could reach 79% of the ultimate value within the first 60 min. The phosphate adsorption process was highly p H-dependent, and MZLCO-45 performed well over a wide p H range of 2.0-8.0. Moreover, MZLCO-45 showed a strong selectivity to phosphate in the presence of competing ions (Cl^(-), NO_(3)^(-), SO_(4)^(2-), HCO_(3)^(-), Ca^(2+), and Mg^(2+)) and a good reusability using the eluent of Na OH/Na Cl mixture, then 64% adsorption capacity remained after ten recycles. The initial 2.0 mg P/L in municipal wastewater and surface water could be efficiently reduced to below 0.1mg P/L by 0.07 g/L MZLCO-45, and the phosphate removal efficiencies were 95.7% and 96.21%, respectively. Phosphate adsorption mechanisms by MZLCO-45 could be attributed to electrostatic attraction and the inner-sphere complexation via ligand exchange forming Zr/La-O-P, -OH and CO_(3)^(2-)groups on MZLCO-45 surface played important roles in the ligand exchange process. The existence of oxygen vacancies could accelerate the phosphate absorption rate of the MZLCO-45 composites.

关键词： Fe3O4 loaded amorphous Zr-La(carbonate)oxides Phosphate adsorption performance Regeneration Mechanism Real water treatment

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Performance evaluation of high/ultra-high-degree global geopotential models over Vietnam using GNSS/leveling data

引用

Geodesy and Geodynamics 2023年第5期14卷 500-512页

作者： Hoa Thi Pham Sten Claessens Michael Kuhn Joseph Awange school of Earth and Planetary Sciences Spatial Sciences DisciplineCurtin UniversityPerthAustralia Faculty of Surveying Mapping and Geographic InformationHanoi University of Natural Resources and EnvironmentHanoiViet Nam

The availability of many high-degree Global Geopotential Models(GGMs), namely EGM2008, EIGEN-6C4,GECO, SGG-UGM-1, SGG-UGM-2, XGM2019e_2159, and GGMPlus, challenges users regarding which model is best for Vietnam. This study, therefore, evaluates their performance by comparing them with GNSS/leveling data over Vietnam. Results show that their absolute and relative performances are largely independent of topographic conditions and geographical location and can be ranked into three classes:(1)XGM2019e_2159 has the highest accuracy,(2) the models EIGEN-6C4, GECO, SGG-UGM-1, SGG-UGM-2, and GGMPlus, have a very similar level of medium accuracy, while(3) EGM2008 is found to be the least accurate. In an absolute sense, the differences between GNSS/leveling and EGM2008-based height anomalies have a standard deviation(STD) of 0.290 ± 0.010 m, whereas, for XGM2019e_2159, this is 0.156 ± 0.006 *** other models have STDs of(0.18-0.19) ± 0.007 m. Regarding relative performance without fitting, all GGMs have comparable accuracies for baseline length of 5-20 km, while for baselines longer than 20 km,the STD of XGM2019e_2159 is 1.5 ppm-0.5 ppm(approximately 19%-40%) lower compared with EGM2008, and 0.5 ppm-0.25 ppm(approximately 7%-36%) lower compared with EIGEN6C4, GECO,SGG-UGM-1, SGG-UGM-2, and GGMPlus. In addition, the STDs decrease significantly from 20 to 12 ppm in the range of 5-10 km, slightly from 12 to 6 ppm for 10-35 km, very slightly from 6 to 2.5 ppm for35-200 km, and then remain almost unchanged for longer baselines. After fitting, the relative accuracies of all GGMs are at the same level with negligible STD/RMSE values. Furthermore, only EGM2008 experiences significant regional differences, while other GGMs show more homogeneous spatial variation of absolute accuracy over Vietnam. These findings can contribute to the development of local quasigeoid models in Vietnam and may be helpful with the improvement of GGMs in the future.

关键词： GGM Evaluation GNSS/Leveling EGM2008 EIGEN-6C4 GECO SGG-UGM-1 SGG-UGM-2 XGM2019e_2159 GGMPlus

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Ecological Barrier Deterioration Driven by Human Activities Poses Fatal Threats to Public Health due to Emerging Infectious Diseases

引用

Engineering 2022年第3期8卷 155-166页

作者： Dayi Zhang Yunfeng Yang Miao Li Yun Lu Yi Liu Jingkun Jiang Ruiping Liu Jianguo Liu Xia Huang Guanghe Li Jiuhui Qu school of environment Tsinghua UniversityBeijing 100084China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

The coronavirus disease 2019(COVID-19)and concerns about several other pandemics in the 21st century have attracted extensive global *** emerging infectious diseases threaten global public health and raise urgent studies on unraveling the underlying mechanisms of their transmission from animals to *** numerous works have intensively discussed the cross-species and endemic barriers to the occurrence and spread of emerging infectious diseases,both types of barriers play synergistic roles in wildlife *** far,there is still a lack of a complete understanding of viral diffusion,migration,and transmission in ecosystems from a macro *** this review,we conceptualize the ecological barrier that represents the combined effects of cross-species and endemic barriers for either the natural or intermediate hosts of *** comprehensively discuss the key influential factors affecting the ecological barrier against viral transmission from virus hosts in their natural habitats into human society,including transmission routes,contact probability,contact frequency,and viral *** the significant impacts of human activities and global industrialization on the strength of the ecological barrier,ecological barrier deterioration driven by human activities is critically analyzed for potential *** climate change can trigger and expand the range of emerging infectious diseases,and human disturbances promote higher contact frequency and greater transmission *** addition,globalization drives more transmission routes and produces new high-risk regions in city *** review aims to provide a new concept for and comprehensive evidence of the ecological barrier blocking the transmission and spread of emerging infectious *** also offers new insights into potential strategies to protect the ecological barrier and reduce the wide-ranging risks of emerging infectious diseases to public health.

关键词： Emerging infectious diseases Virus Ecological barrier

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Digitalization of inverting filter shaping circuit for nuclear pulse signals

引用

Nuclear Science and Techniques 2020年第9期31卷 16-24页

作者： Huai-Qiang Zhang Hong-Tao Shi Zhuo-Dai Li Yu-Wen Li State Key Laboratory of Nuclear Resources and environment East China University of TechnologyNanchang 330013China school of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

In the design of filter shaping circuits for nuclear pulse signals,inverting filter shaping circuits perform better than non-inverting filter shaping *** these circuits facilitate changing the phase of a pulse signal,they are widely used in processing nuclear pulse *** this study,the transfer functions of four types of inverting filter shaping circuits,namely the common inverting filter shaping,improved inverting filter shaping,multiple feedback low-pass filter shaping,and third-order multiple feedback low-pass filter shaping,in the Laplacian domain,are *** establish the numerical recursive function models and digitalize the four circuits,obtain the transfer functions in the Z domain,and analyze the filter performance and amplitude-frequency response characteristics in the frequency *** on the actual nuclear pulse signal of the Si-PIN detector,we realize four types of inverting digital *** results show that under the same shaping parameters,the common inverting digital shaping has better amplitude extraction characteristics,the third-order multiple feedback low-pass digital shaping has better noise suppression performance,and the multiple feedback digital shaping takes into account both pulse amplitude extraction and noise suppression performance.

关键词： Nuclear pulse signal Inverting filter shaping circuit Digital shaping Amplitude-frequency response

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Infl uencing Mechanism and Interaction of Muscovite on Thermal Decomposition of Ammonium Polyphosphate

引用

Journal of Wuhan University of Technology(Materials Science) 2016年第2期31卷 334-339页

作者：胡盛 CHEN Fei LI Junguo 沈强 ZHANG Lianmeng State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070 China school of Chemical and environment Engineering Hubei University for Nationalities Enshi 445000 China

The interaction mechanism and phase evolution of ammonium polyphosphate（APP）mixed with muscovite（APP/muscovite）were studied by TG,XRD and SEM,respectively,during *** the temperature is not higher than 300 ℃,muscovite has no effect on the thermaldecomposition of APP,and the initialdecomposition temperature of APP/muscovite at 283 ℃ is basically the same as the APP at 295 ℃,and the main thermaldecomposition products are polyphosphoric acid and NH_4H_2PO_4 at 300 ℃.The polyphosphoric acid,the decomposition products of APP,can enable K and Siout of muscovite and interact with muscovite chemically to generate Al_2O_3·2SiO_2,α-SiO_2 and phosphates（AlPO_4 and K_5P_3O_（10））compounds during 400 ℃-800 ℃,which own obvious adhesive phenomenon and porous structure with the apparent porosity of 58.4%.Further reactions between phosphates other than reactions among Al_2O_3·2SiO_2 and α-SiO_2 can generate KAlP_2O_7 at 1 000 ℃ and the density of residualproduct is improved by low melting point phosphate filling pore to form relatively dense structure and decrease the apparent porosity to 44.4%.The flame resistant and self-supported ceramic materials are expected to enhance the fire-retarding synergistic effect between APP and muscovite.

关键词： ammonium polyphosphate(APP) muscovite thermal decomposition influencing mechanism interaction

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Reproduction of Hedysarum scoparium (Fabaceae) in patched habitat is pollen limited,but not just pollinator limited

引用

Journal of Arid Land 2012年第1期4卷 19-28页

作者： ChengChen PAN LinDe LIU HaLin ZHAO JiLiang LIU YueLi HOU Li ZHANG Cold and Arid Regions environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China school of Life Sciences Ludong University Yantai 264039 China

Pollen limitation of plant reproduction occurs across Angiosperms, particularly those in patched habitats We investigated the, relationship between pollen limitation and patch variables （patch size, visitation frequency） in the desert plant Hedysarum scoparium （Fabaceae）, which is an important xerophyte in the arid and semi-arid regions of Northwest China and can grow well as a pioneer plant in shifting sand dunes. We observed insect visitation to H. scoparium over two flowering seasons and estimated pollen limitation using fruit set and seed production. Our results indicate that fruit set and seed production increased significantly with pollen supplementation compared with open pollination. Hedysarum scoparium was pollinated by over 8 species of bees, with 88.4% of visits made by introduced honeybees （Apis mellifera）. Bee visitation varied significantly among the patches of habitats, but not associated with patch size of habitat. In general, pollen limitation occurred more strongly during fruit set than during seed production. The patches that received higher rates of pollinator visits were less pollen limited for fruit set. Pollen limitation for seed production, however, was not associated with pollinator visitation frequency. We conclude that pollen limitation in H. scoparium was caused by more than one reason, not just pollinator visits.

关键词： Hedysarum scoparium pollen limitation pollinator limitation honeybees fruit set seed production

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Stress corrosion cracking behavior of buried oil and gas pipeline steel under the coexistence of magnetic field and sulfate-reducing bacteria

引用

Petroleum Science 2024年第2期21卷 1320-1332页

作者： Jian-Yu He Fei Xie Dan Wang Guang-Xin Liu Ming Wu Yue Qin College of Petroleum Engineering Liaoning Petrochemical UniversityFushun113001LiaoningChina Key Laboratory of Oil and Gas Storage and Transportation Technology in Liaoning Province Fushun113001LiaoningChina State Key Joint Laboratory of environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China PipeChina West East Gas Pipeline Company Shanghai200120China

Magnetic field and microorganisms are important factors influencing the stress corrosion cracking(SCC)of buried oil and gas pipelines. Once SCC occurs in buried pipelines, it will cause serious hazards to the soil environment. The SCC behavior of X80 pipeline steel under the magnetic field and sulfate-reducing bacteria(SRB) environment was investigated by immersion tests, electrochemical tests, and slow strain rate tensile(SSRT) tests. The results showed that the corrosion and SCC sensitivity of X80 steel decreased with increasing the magnetic field strength in the sterile environment. The SCC sensitivity was higher in the biotic environment inoculated with SRB, but it also decreased with increasing magnetic field strength, which was due to the magnetic field reduces microbial activity and promotes the formation of dense film layer. This work provided theoretical guidance on the prevention of SCC in pipeline steel under magnetic field and SRB coexistence.

关键词： Magnetic field Sulfate-reducing bacteria Film layer Stress corrosion cracking Oil and gas pipelines

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Tillage Pedogenesis of Purple Soils in Southwestern China

引用

Journal of Mountain Science 2009年第2期6卷 205-210页

作者： HE Xiubin BAO Yuhai NAN Hongwei XIONG Donghong WANG Li LIU Yanfeng ZHAO Jingbo Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu 610041 China Graduate school of the Chinese Academy of Sciences Beijing 100049 China Shaanxi Normal University Xi'an 710062 China

Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO Taxonomy or Entisols in USDA Taxonomy, are formed from purple rocks of the Trias- Cretaceous system, have been developed or at least accelerated the development due to continual tillage operation, especially digging and ridging. The present study took micromorphological investigation on the sedimentary rocks and the soils under different operations of tillage. Results show that the purple rock of Feixiangguan Formation of the Trias system （Tlf） is the easiest to physical weathering and the most fertile soil material enriched in nutrients, and it has been, therefore, mostly cultivated and intensively tilled around the year. It has the fastest soil formation rate. Soil formation rate in the cropland with conventional tillage is higher than that in the forestiand and the grassland. It implies that the artificial brokenness and tillage disturbance play a great role in physical weathering and initiating soil formation processes.

关键词： Tillage impact pedogenesis purple soil micromorphology southwestern China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of low-energy proton on the microstructure, martensitic transformation and mechanical properties of irradiated Ni-rich TiNi alloy thin films

引用

International Journal of Minerals,Metallurgy and Materials 2020年第4期27卷 538-543页

作者： Hai-zhen Wang Yun-dong Zhao Yue-hui Ma Zhi-yong Gao Science and Technology on Materials Performance Evaluation in Space environment Laboratory School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China Lanzhou Seemine SMA Co.Ltd. Lanzhou 730010China

Ni–48.5at%Ti thin films were irradiated in the austenite phase by different energy-level protons at a dose rate of 1.85×1012 p/(cm2·s),and the total dose was 2.0×1016 p/*** microstructures of the thin films before and after irradiation were evaluated by transmission electron microscopy(TEM)and grazing-incidence X-ray diffraction(GIXRD),which showed that the volume fraction of Ti3Ni4 phase elevated with proton energy *** influence of proton irradiation on the transformation behavior of the TiNi thin films was investigated by differential scanning calorimetry(DSC).Compared with the unirradiation film,the reverse transformation start temperatures(As)decreased by about 3°C after 120 keV *** proton irradiation also had a significant effect on the mechanical properties of the TiNi thin *** 120 keV energy proton-irradiation,the fracture strength increased by 8.44%,and the critical stress increased by 21.1%.In addition,the nanoindenter measurement image showed that the hardness of the thin films increased with the increase of proton-irradiation *** may be due to the defects caused by irradiation,which strengthen the matrix.

关键词： TiNi thin film proton irradiation microstructure martensitic transformation mechanical properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Ultrafast photocatalytic degradation of nitenpyram by 2D ultrathin Bi2WO6:mechanism,pathways and environmental factors

引用

Rare Metals 2022年第7期41卷 2439-2452页

作者： Yuan-Hao Cheng Juan Chen Hui-Nan Che Yan-Hui Ao Bin Liu Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education College of EnvironmentHohai UniversityNanjing 210098China school of Chemical and Biomedical Engineering Nanyang Technological UniversitySingapore 637459Singapore

As a common insecticide,nitenpyram(NTP)seriously threatens the human health and environmental *** this work,a visible-light-responsive photocata-lyst two-dimensional(2D)Bi_(2)WO_(6) was synthesized and applied to degrade *** with bulk Bi_(2)WO_(6),the 2D Bi_(2)WO_(6)exhibits better photocatalytic performance for NTP degradation under visible-light *** enhanced activity can be ascribed to the unique 2D struc-ture which would induce to higher efficiency of carrier ***,hole(h+)plays a major role(and·O^(2-))in the degradation of *** on the interme-diates detected by high-performance liquid chromatogra-phy-mass spectrometry(HPLC-MS),the degradation pathway of NTP was *** addition,the influence of typical environmental factors(pH,water matrix,inorganic cations and common anions)on the degradation of NTP was also *** work not only helps people to understand the degradation of pesticides in actual water bodies,but also provides reference for the subsequent treatment of agricultural wastewater.

关键词： Photocatalysis Two-dimensional(2D)Bi_(2)WO_(6) Nitenpyram Degradation pathway

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：