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A combination of straw incorporation and polymer-coated urea offsets soil ammonia and nitrous oxide emissions in winter wheat fields
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作者 Xiaoyun Wang Yajie Tian +3 位作者 Qianhui Zhang Zhengxin Zhao Rui Wang Huanjie Cai 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1718-1736,共19页
The combined effects of straw incorporation(SI)and polymer-coated urea(PCU)application on soil ammonia(NH_(3))and nitrous oxide(N_(2)O)emissions from agricultural fields have not been comprehensively evaluated in Nort... The combined effects of straw incorporation(SI)and polymer-coated urea(PCU)application on soil ammonia(NH_(3))and nitrous oxide(N_(2)O)emissions from agricultural fields have not been comprehensively evaluated in Northwest China.We conducted a two-year field experiment to assess the effects of combining SI with either uncoated urea(U)or PCU on soil NH_(3)emissions,N_(2)O emissions,winter wheat yields,yield-scaled NH_(3)(/NH_(3)),and yield-scaled N_(2)O(/N_(2)O).Five treatments were investigated,no nitrogen(N)fertilizer(N_(0)),U application at 150 kg N ha-1 with and without SI(SI+U and S_(0)+U),and PCU application at 150 kg N ha^(-1) with and without SI(SI+PCU and S_(0)+PCU).The results showed that the NH_(3);emissions increased by 20.98-34.35%following Sl compared to straw removal,mainly due to increases in soil ammonium(NH_(4)^(+)-N)content and water-flled pore space(WFPS).SI resulted in higher N_(2)O emissions than under the So scenario by 13.31-49.23%due to increases in soil inorganic N(SIN)contents,WFPS,and soil microbial biomass.In contrast,the PCU application reduced the SIN contents compared to the U application,reducing the NH_(3)and N_(2)O emissions by 45.99-58.07 and 18.08-53.04%,respectively.Moreover,no significant positive effects of the SI or PCU applications on the winter wheat yield were observed.The lowest /NH_(3) and /N_(2)O values were observed under the S_(0)+PCU and SI+PCU treatments.Our results suggest that single PCU applications and their combination with straw are the optimal agricultural strategies for mitigating gaseous N emissions and maintaining optimal winter wheat yields in Northwest China. 展开更多
关键词 straw incorporation polymer-coated urea NH_(3)and N_(2)O emissions winter wheat yields
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Magnesium incorporation activates perovskite cobaltites toward efficient and stable electrocatalytic oxygen evolution 被引量:2
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作者 Siyu Pan Zilin Ma +6 位作者 Wenying Yang Biaokui Dongyang Huizhi Yang Shimin Lai Feifei Dong Xixian Yang Zhan Lin 《Materials Reports(Energy)》 2023年第3期55-61,共7页
Cobalt-rich perovskite oxides play a paramount role in catalyzing oxygen evolution reaction(OER)on account of their acceptable intrinsic activity but are still challenging due to the high costs and undesired stability... Cobalt-rich perovskite oxides play a paramount role in catalyzing oxygen evolution reaction(OER)on account of their acceptable intrinsic activity but are still challenging due to the high costs and undesired stability.In response to the defects,herein,the Mg-incorporated perovskite cobaltite SrCo_(0.6)Fe_(0.3M)g_(0.1)O_(3-δ)(SCFM-0.1)is proposed as a novel earth-abundant and durable OER electrocatalyst.A well-consolidated cubic-symmetry structure and more active oxygen intermediates are enabled upon Mg substitution.Hence,the optimized SCFM-0.1 perovskite oxide achieves prominent OER electrocatalytic performance,that is,a low overpotential of only 320 mV at 10 mA cm^(-2),a small Tafel slope of 65 mV dec^(-1),as well as an outstanding durability within 20 h,substantially outperforming that of the pristine SrCo_(0.7)Fe_(0.3)O_(3-δ)and benchmark Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)and IrO_(2) catalysts.The strong pHdependent behavior associated with lattice oxygen activation mechanism for SCFM-0.1 catalyst is also confirmed.This work paves a unique avenue to develop cost-effective and robust perovskite cobaltites for efficient OER electrocatalysis. 展开更多
关键词 PEROVSKITE Oxygen evolution reaction ELECTROCATALYST Mg incorporation Lattice oxygen activation
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Carbon Dioxide, Methane, and Nitrous Oxide Emissions from a Rice-Wheat Rotation as Affected by Crop Residue Incorporation and Temperature 被引量:29
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作者 ZOU Jianwen(邹建文) +7 位作者 HUANG Yao(黄耀) ZONG Lianggang(宗良纲) ZHENG Xunhua(郑循华) WANG Yuesi(王跃思) 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第5期691-698,共8页
Field measurements were made from June 2001 to May 2002 to evaluate the effect of crop residue application and temperature on CO2, CH4, and N2O emissions within an entire rice-wheat rotation season. Rapeseed cake and ... Field measurements were made from June 2001 to May 2002 to evaluate the effect of crop residue application and temperature on CO2, CH4, and N2O emissions within an entire rice-wheat rotation season. Rapeseed cake and wheat straw were incorporated into the soil at a rate of 2.25 t hm(-2) when the rice crop was transplanted in June 2001. Compared with the control, the incorporation of rapeseed cake enhanced the emissions of CO2, CH4, and N2O in the rice-growing season by 12.3%, 252.3%, and 17.5%, respectively, while no further effect was held on the emissions of CO2 and N2O in the following wheat-growing season. The incorporation of wheat straw enhanced the emissions of CO2 and CH4 by 7.1% and 249.6%, respectively, but reduced the N2O emission by 18.8% in the rice-growing season. Significant reductions of 17.8% for the CO2 and of 12.9% for the N2O emission were observed in the following wheat-growing season. A positive correlation existed between the emissions of N2O and CO2 (R-2 = 0.445, n = 73,p < 0.001) from the rice-growing season when N2O was emitted. A trade-off relationship between the emissions of CH4 and N2O was found in the rice-growing season. The CH4 emission was significantly correlated with the CO2 emission for the period from rice transplantation to field drainage, but not for the entire rice-growing season. In addition, air temperature was found to regulate the CO2 emissions from the non-waterlogged period over the entire rice-wheat rotation season and the N2O emissions from the nonwaterlogged period of the rice-growing season, which can be quantitatively described by an exponential function. The temperature coefficient (Q(10)) was then evaluated to be 2.3+/-0.2 for the CO2 emission and 3.9+/-0.4 for the N2O emission, respectively. 展开更多
关键词 emissions of CO2 CH4 and N2O rice-wheat rotation incorporation of crop residues temperature
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Impacts of Fertilization Alternatives and Crop Straw Incorporation on N_2O Emissions from a Spring Maize Field in Northeastern China 被引量:13
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作者 YANG Li WANG Li-gang +2 位作者 LI Hu QIU Jian-jun LIU Hui-ying 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第4期881-892,共12页
Spring maize is one of the most popular crops planted in northeastem China. The cropping systems involving spring maize have been maintaining high production through intensive management practices. However, the high r... Spring maize is one of the most popular crops planted in northeastem China. The cropping systems involving spring maize have been maintaining high production through intensive management practices. However, the high rates of nitrogen (N) fertilizers application could have introduced a great amount of nitrous oxide (N2O) into the atmosphere. It is crucial for sustaining the maize production systems to reduce N2O emissions meanwhile maintaining the optimum yields by adopting alternative farming management practices. The goal of this study was to evaluate effects of alternative fertilization and crop residue management practices on N2O emission as well as crop yield for a typical maize field in northeastern China. Field experiments were conducted during the 2010-2011 maize growing seasons (from early May to late September) in Liaoning Province, northeastern China. N2O fluxes were measured at the field plots with six different treatments including no N fertilizer use (CK), farmers' conventional N fertilizer application rate (FP), reduced N fertilizer rate (OPT), reduced N fertilizer rate combined with crop straw amendment (OPTS), slow-release N fertilizer (CRF), and reduced N fertilizer rate combined with nitrification inhibitor (OPT+DCD). The static chamber method combined with gas chromatography technique was employed to conduct the measurements of N2O fluxes. The field data showed that N2O emissions varied across the treatments. During the maize growing season in 2010, the total N2O emissions under the treatments of CK, FP, OPT, OPTS, and CRF were 0.63, 1.11, 1.03, 1.26, and 0.98 kg N ha-1, respectively. The seasonal cumulative N2O emissions were 0.54, 1.07, 0.96, 1.12, and 0.84 kg N ha1, respectively, under CK, FP, OPT, OPTS, and OPT+DCD in 2011. In comparison with FP, CRF or OPT+DCD reduced the N2O emissions by 12 or 21%, respectively, while the crop yields remained unchanged. The results indicate that the reduction of N-fertilizer application rate in combination with the slow-release fertilizer type or nitrification inhibitor could effectively mitigate N2O emissions from the tested field. The incorporation of crop residue didn't show positive effect on mitigating N2O emissions from the tested cropping system. The field study can provide useful information for the on-going debate on alternative N fertilization strategies and crop straw management in China. However, further studies would be needed to explore the long-term impacts of the alternative management practices on a wide range of environmental services. 展开更多
关键词 nitrogen fertilization straw incorporation nitrous oxide crop yield spring maize
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Effects of the incorporation amounts of CdS and Cd(SCN_(2)H_(4))_(2)Cl_(2)on the performance of perovskite solar cells 被引量:5
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作者 Jihong Zheng Liangxin Zhu +4 位作者 Zhitao Shen Fumin Li Lanyu Ling Huilin Li Chong Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第2期283-291,共9页
An excellent organolead halide perovskite film is important for the good performance of perovskite solar cells(PSCs).However,defects in perovskite crystals can affect the photovoltaic properties and stability of solar... An excellent organolead halide perovskite film is important for the good performance of perovskite solar cells(PSCs).However,defects in perovskite crystals can affect the photovoltaic properties and stability of solar cells.To solve this problem,this study incorporated a complex of Cd S and Cd(SCN_(2)H_(4))_(2)Cl_(2)into the CH_(3)NH_(3)Pb I_(3)active layer.The effects of different doping concentrations of Cd S and Cd(SCN_(2)H_(4))_(2)Cl_(2)on the performance and stability of PSCs were analyzed.Results showed that doping appropriate incorporation concentrations of Cd S and Cd(SCN_(2)H_(4))_(2)Cl_(2)in CH_(3)NH_(3)Pb I_(3)can improve the performance of the prepared solar cells.In specific,Cd S and Cd(SCN_(2)H_(4))_(2)Cl_(2)can effectively passivate the defects in perovskite crystals,thereby suppressing the charge recombination in PSCs and promoting the charge extraction at the TiO_(2)/perovskite interface.Due to the reduction of perovskite crystal defects and the enhancement of compactness of the Cd S:Cd(SCN_(2)H4)_(2)Cl_(2):CH_(3)NH_(3)Pb I_(3)composite film,the stability of PSCs is significantly improved. 展开更多
关键词 perovskite solar cells charge extraction defect passivation incorporation concentration
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Effect of Manganese Incorporation Manner on an Iron-Based Catalyst for Fischer-Tropsch Synthesis 被引量:5
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作者 Tingzhen Li Yong Yang +5 位作者 Chenghua Zhang Zhichao Tao Haijun Wan Xia An Hongwei Xiang Yongwang Li 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第3期244-251,共8页
A systematic study was undertaken to investigate the effects of the manganese incorporation manner on the textural properties, bulk and surface phase compositions, reduction/carburization behaviors, and surface basici... A systematic study was undertaken to investigate the effects of the manganese incorporation manner on the textural properties, bulk and surface phase compositions, reduction/carburization behaviors, and surface basicity of an iron-based Fischer-Tropsch synthesis (FTS) catalyst. The catalyst samples were characterized by N2 physisorption, X-ray photoelectron spectroscopy (XPS), H2 (or CO) temperature-programmed reduction (TPR), CO2 temperature-programmed desorption (TPD), and M5ssbauer spectroscopy. The FTS performance of the catalysts was studied in a slurry-phase continuously stirred tank reactor (CSTR). The characterization results indicated that the manganese promoter incorporated by using the coprecipitation method could improve the dispersion of iron oxide, and decrease the size of the iron oxide crystallite. The manganese incorporated with the impregnation method is enriched on the catalyst's surface. The manganese promoter added with the impregnation method suppresses the reduction and carburization of the catalyst in H2, CO, and syngas because of the excessive enrichment of manganese on the catalyst surface. The catalyst added manganese using the coprecipitation method has the highest CO conversion (51.9%) and the lowest selectivity for heavy hydrocarbons (C12+). 展开更多
关键词 Fischer-Tropsch synthesis iron-based catalyst manganese promoter incorporation manner
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Perfection of Perovskite Grain Boundary Passivation by Rhodium Incorporation for Efficient and Stable Solar Cells 被引量:7
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作者 Wei Liu Nanjing Liu +7 位作者 Shilei Ji Hongfeng Hua Yuhui Ma Ruiyuan Hu Jian Zhang Liang Chu Xing’ao Li Wei Huang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第9期203-213,共11页
Organic cation and halide anion defects are omnipresent in the perovskite films,which will destroy perovskite electronic structure and downgrade the properties of devices.Defect passivation in halide perovskites is cr... Organic cation and halide anion defects are omnipresent in the perovskite films,which will destroy perovskite electronic structure and downgrade the properties of devices.Defect passivation in halide perovskites is crucial to the application of solar cells.Herein,tiny amounts of trivalent rhodium ion incorporation can help the nucleation of perovskite grain and passivate the defects in the grain boundaries,which can improve efficiency and stability of perovskite solar cells.Through first-principle calculations,rhodium ion incorporation into the perovskite structure can induce ordered arrangement and tune bandgap.In experiment,rhodium ion incorporation with perovskite can contribute to preparing larger crystalline and uniform film,reducing trap-state density and enlarging charge carrier lifetime.After optimizing the content of 1% rhodium,the devices achieved an efficiency up to 20.71% without obvious hysteresis,from 19.09% of that pristine perovskite.In addition,the unencapsulated solar cells maintain 92% of its initial efficiency after 500 h in dry air.This work highlights the advantages of trivalent rhodium ion incorporation in the characteristics of perovskite solar cells,which will promote the future industrial application. 展开更多
关键词 Perovskite solar cells Grain boundary passivation Rhodium incorporation
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Long-term straw incorporation increases rice yield stability under high fertilization level conditions in the rice–wheat system 被引量:4
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作者 Jianwei Zhang Weiwei Li +4 位作者 Yan Zhou Yanfeng Ding Lei Xu Yu Jiang Ganghua Li 《The Crop Journal》 SCIE CSCD 2021年第5期1191-1197,共7页
Straw incorporation is a global common practice to improve soil fertility and rice yield.However,the effect of straw incorporation on rice yield stability is still unknown,especially under high fertilization level con... Straw incorporation is a global common practice to improve soil fertility and rice yield.However,the effect of straw incorporation on rice yield stability is still unknown,especially under high fertilization level conditions.Here,we reported the effect of straw returning on rice yield and yield stability under high fertilization levels in the rice–wheat system over nine years.The results showed that straw incorporation did not significantly affect the average rice yield of nine years.Straw incorporation reduced the coefficient of variation of rice yield by 25.8%and increased the sustainable yield index by 8.2%.The rice yield positively correlated with mean photosynthetically active radiation (PAR) of rice growth season and the effects of straw incorporation on rice yield depended on the PAR.Straw incorporation increased the rice yield by 5.4%in the low PAR years,whereas it did not affect the rice yield in the high PAR years.Long-term straw incorporation lowered soil bulk density but improved the soil organic matter,total N,available N,available P,and available K more strongly than straw removal.Our findings suggest that straw incorporation can increase rice yield stability through improving the resistance of rice plant growth to low PAR. 展开更多
关键词 Long-term straw incorporation Rice yield STABILITY Rice-wheat system PAR
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Effect of silicon precursor on silicon incorporation in SAPO-11 and their catalytic performance for hydroisomerization of n-octane on Pt-based catalysts 被引量:3
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作者 Zhichao Yang Jilong Li +1 位作者 Yunqi Liu Chenguang Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第4期688-694,共7页
SAPO-11 molecular sieves were synthesized using silica sol, hydrophilic fumed silica, and tetraethyl orthosilicate(TEOS) as silicon precursors. Their physicochemical properties were characterized using XRD,SEM, nitr... SAPO-11 molecular sieves were synthesized using silica sol, hydrophilic fumed silica, and tetraethyl orthosilicate(TEOS) as silicon precursors. Their physicochemical properties were characterized using XRD,SEM, nitrogen adsorption-desorption, Py-IR, NH;-TPD, EDS, and;Al,;P,;Si MAS NMR techniques. The catalytic performance was assessed in the hydroisomerization of n-octane. The results showed that the silicon precursors influenced the physicochemical properties and catalytic performance of SAPO-11. SAPO-11 synthesized using hydrophilic fumed silica as silicon precursor showed higher silicon distribution and had more medium acid sites. SAPO-11 synthesized using TEOS as silicon precursor had more silicon content, but more silicon islands formed in its framework. The depolymerization of silicon precursors might affect the silicon content and distribution in SAPO-11. In the hydroisomerization of n-octane, the catalytic activity strongly depended on the number of medium acid sites instead of the number of total acid sites.SAPO-11 synthesized using hydrophilic fumed silica as silicon precursor exhibited higher catalytic activity than the other samples because it has more medium acid sites. 展开更多
关键词 SAPO-11 Silicon precursor Silicon incorporation Acid sites HYDROISOMERIZATION N-OCTANE
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Promotional effects of Er incorporation in CeO_2(ZrO_2)/TiO_2 for selective catalytic reduction of NO by NH_3 被引量:4
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作者 Qijie Jin Yuesong Shen +2 位作者 Shemin Zhu Xihong Li Min Hu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第9期1521-1529,共9页
A series CeO2(ZrO2)/TiO2 catalysts were modified with Er using a sol-gel method.The catalytic activity of the obtained catalysts in the selective catalytic reduction(SCR) of NO with NH3 was investigated to determi... A series CeO2(ZrO2)/TiO2 catalysts were modified with Er using a sol-gel method.The catalytic activity of the obtained catalysts in the selective catalytic reduction(SCR) of NO with NH3 was investigated to determine the appropriate Er dosage.The catalysts were characterized using X-ray diffraction,N2 adsorption,NH3 temperature-programmed desorption,H2 temperature-programmed reduction,photoluminescence spectroscopy,electron paramagnetic resonance spectroscopy,and X-ray photoelectron spectroscopy.The results showed that the optimum Er/Ce molar ratio was 0.10;this catalyst had excellent resistance to catalyst poisoning caused by vapor and sulfur and gave more than 90% NO conversion at 220–395 ℃ and a gas hourly space velocity of 71 400 h^-1.Er incorporation increased the Ti^3+ concentrations,oxygen storage capacities,and oxygen vacancy concentrations of the catalysts,resulting in excellent catalytic performance.Er incorporation also decreased the acid strength and inhibited growth of TiO2 and CeO2 crystal particles,which increased the catalytic activity.The results show that high oxygen vacancy concentrations and oxygen storage capacities,large amounts of Ti^3+,and low acid strengths give excellent SCR activity. 展开更多
关键词 CeO2(ZrO2)/TiO2 Erbium incorporation Selective catalytic reduction Nitrogen oxide Catalytic performance
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Effects of long-term straw incorporation on nematode community composition and metabolic footprint in a rice–wheat cropping system 被引量:3
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作者 CHEN Yun-feng XIA Xian-ge +4 位作者 HU Cheng LIU Dong-hai QIAO Yan LI Shuang-lai FAN Xian-peng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第8期2265-2276,共12页
Soil nematode communities can provide valuable information about the structure and functions of soil food webs,and are sensitive to agricultural practices,including short-term straw incorporation.However,currently,suc... Soil nematode communities can provide valuable information about the structure and functions of soil food webs,and are sensitive to agricultural practices,including short-term straw incorporation.However,currently,such effects under longterm straw incorporation conditions at different fertility levels are largely unknown.Thus,we conducted a 13-year ongoing experiment to evaluate the effects of long-term straw incorporation on the structure and functions of the soil food web in low and high fertility soils through analyzing its effects on nematode communities,food web indices and metabolic footprints.Four treatments were included:straw removal(–S)under non-fertilized(–NPK)or fertilized(+NPK)conditions;and straw incorporation(+S)under–NPK or+NPK conditions.Soil samples from a 0–20 cm depth layer were collected when wheat and rice were harvested.Compared with straw removal,straw incorporation increased the abundances of total nematodes,bacterivores,plant-parasites and omnivores-predators,as well the relative abundances of omnivores-predators with increases of 73.06,89.29,95.31,238.98,and 114.61%in–NPK soils and 16.23,2.23,19.01,141.38,and 90.23%in+NPK soils,respectively.Regardless of sampling times and fertilization effects,straw incorporation increased the diversity and community stability of nematodes,as indicated by the Shannon-Weaver diversity index and maturity index.Enrichment and structure index did not show significant responses to straw incorporation,but a slight increase was observed in the structure index.The analysis of nematode metabolic footprints showed that straw incorporation increased the plant-parasite footprint and structure footprint by 97.27 and 305.39%in–NPK soils and by 11.29 and 149.56%in+NPK soils,but did not significantly influence enrichment,bacterivore and fungivore footprints.In conclusion,long-term straw incorporation,particularly under a low fertility level,favored the soil nematodes and regulated the soil food web mainly via a top-down effect. 展开更多
关键词 soil nematodes community composition metabolic footprint straw incorporation rice-wheat cropping system top-down effect
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Al-incorporation into Li7La3Zr2O12 solid electrolyte keeping stabilized cubic phase for all-solid-state Li batteries 被引量:4
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作者 Changbin Im Dongwon Park +1 位作者 Hosung Kim Jaeyoung Lee 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第5期1501-1508,共8页
We observe the influence of AI occupancies in Li sites on the formation process of the garnet solid elec- trolyte of Li_7La_3Zr_2O_12 (LLZO). A direct incorporation of AI is first promoted in a Li-insufficient garne... We observe the influence of AI occupancies in Li sites on the formation process of the garnet solid elec- trolyte of Li_7La_3Zr_2O_12 (LLZO). A direct incorporation of AI is first promoted in a Li-insufficient garnet solid electrolyte during the calcination process of 850 ℃ and then the cubic phase of LLZO is obtained after successive annealing step of 1000 ℃. Comparing to pristine LLZO, AI incorporated LLZO shows less formation of Li_2CO_3, keeping crystallographic and physicochemical properties. This AI incorporation im- proves both the ionic conductivity and interfacial resistance to poisoning procedure. 展开更多
关键词 Li_7La_3Zr_2O_12 AI incorporation Garnet solid electrolyte Cubic phase
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S Phase Cell Percentage Normalized BrdU Incorporation Rate, a New Parameter for Determining S Arrest 被引量:2
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作者 ZHAO Peng FU Juan Ling +2 位作者 YAO Bi Yun JIA Yong Rui ZHOU Zong Can 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第3期215-219,共5页
In this study, a new parameter, S phase cell percentage (S fraction) normalized BrdU (SFN-BrdU) incorporation rate, was introduced to detect $ arrest. The results showed a positive linear correlation between the B... In this study, a new parameter, S phase cell percentage (S fraction) normalized BrdU (SFN-BrdU) incorporation rate, was introduced to detect $ arrest. The results showed a positive linear correlation between the BrdU incorporation rate and the S fraction in unperturbed 16HBE cells. Theoretical analysis indicated that only S arrest could result in a decrease in the SFN-BrdU incorporation rate. Additionally, the decrease in SFN-BrdU incorporation rate and the activation of DNA damage checkpoints further demonstrated that S arrest was induced by diethyl sulfate treatment of 16HBE cells. In conclusion, $FN-BrdU incorporation rate can be used to detecting S arrest. 展开更多
关键词 BRDU RATE S Phase Cell Percentage Normalized BrdU incorporation Rate a New Parameter for Determining S Arrest
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Study of intracellular anabolism of 5-fluorouracil and incorporation in nucleic acids based on an LC-HRMS method 被引量:1
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作者 Christelle Machon Frederic Catez +7 位作者 Nicole Dalla Venezia Floriane Vanhalle Laetitia Guyot Anne Vincent Maxime Garcia Beatrice Roy Jean-Jacques Diaz Jerome Guitton 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第1期77-87,共11页
5-Fluorouracil(5-FU)is an anticancer drug extensively used for different cancers.Intracellular metabolic activation leads to several nucleoside and nucleotide metabolites essential to exert its cytotoxic activity on m... 5-Fluorouracil(5-FU)is an anticancer drug extensively used for different cancers.Intracellular metabolic activation leads to several nucleoside and nucleotide metabolites essential to exert its cytotoxic activity on multiple cellular targets such as enzymes,DNA and RNA.In this paper,we describe the development of a method based on liquid chromatography coupled with high resolution mass spectrometry suitable for the simultaneous determination of the ten anabolic metabolites(nucleoside,nucleotide and sugar nucleotide)of 5-FU.The chromatographic separationwas optimized on a porous graphitic carbon column allowing the analysis of the metabolites of 5-FU as well as endogenous nucleotides.The detection was performed on an Orbitrap■tandem mass spectrometer.Linearity of the method was verified in intracellular content and in RNA extracts.The limit of detection was equal to 12 pg injected on column for nucleoside metabolites of 5-FU and 150 pg injected on column for mono-and tri-phosphate nucleotide metabolites.Matrix effect was evaluated in cellular contents,DNA and RNA extracts for nucleoside and nucleotides metabolites.The method was successfully applied to i)measure the proportion of each anabolic metabolite of 5-FU in cellular contents,ii)follow the consequence of inhibition of enzymes on the endogenous nucleotide pools,iii)study the incorporation of metabolites of 5-FU into RNA and DNA,and iv)to determine the incorporation rate of 5-FUrd into 18 S and 28 S sub-units of rRNA. 展开更多
关键词 5-FLUOROURACIL LC-MS-HRMS NUCLEOTIDE RNA DNA incorporation rate
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Magnesium incorporation efficiencies in Mg_xZn_(1-x)O films on ZnO substrates grown by metalorganic chemical vapor deposition 被引量:1
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作者 胡启昌 丁凯 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期465-470,共6页
We investigate the magnesium(Mg) incorporation efficiencies in MgxZn1-xO films on c-plane Zn-face ZnO substrates by using metalorganic chemical vapor deposition(MOCVD) technique. In order to deposit high quality M... We investigate the magnesium(Mg) incorporation efficiencies in MgxZn1-xO films on c-plane Zn-face ZnO substrates by using metalorganic chemical vapor deposition(MOCVD) technique. In order to deposit high quality MgxZn1-xO films,atomically smooth epi-ready surfaces of the hydrothermal grown ZnO substrates are achieved by thermal annealing in O2 atmosphere and characterized by atomic force microscope(AFM). The AFM, scanning electron microscope(SEM),and x-ray diffraction(XRD) studies demonstrate that the MgxZn1-xO films each have flat surface and hexagonal wurtzite structure without phase segregation at up to Mg content of 34.4%. The effects of the growth parameters including substrate temperature, reactor pressure and Ⅵ/Ⅱ ratio on Mg content in the films are investigated by XRD analysis based on Vegard's law, and confirmed by photo-luminescence spectra and x-ray photoelectron spectroscopy as well. It is indicated that high substrate temperature, low reactor pressure, and high Ⅵ/Ⅱratio are good for obtaining high Mg content. 展开更多
关键词 MGXZN1-XO MOCVD incorporation efficiency ZnO bulk crystal
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Evaluation of Erythrocyte Iron Incorporation in Beijing Prepubertal Children Using a Single Stable Isotope Tracer Method 被引量:1
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作者 ZHANG Yu LI Ya Jie +5 位作者 REN Tong Xiang LIU Xiao Bing YANG Li Chen PAO Jian Hua WANG Jurr YANG Xiao Guang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第6期414-420,共7页
Objective To analyze the rate of erythrocyte iron incorporation and provided guidance for the iron nutrition for prepubertal children.Methods Fifty-seven prepubertal children of Beijing were involved in this study and... Objective To analyze the rate of erythrocyte iron incorporation and provided guidance for the iron nutrition for prepubertal children.Methods Fifty-seven prepubertal children of Beijing were involved in this study and each subject was orally administered 3 mg of 57 Fe twice daily to obtain a total of 30 mg 57 Fe after a 5-d period. The stable isotope ratios in RBCs were determined in 14 th day, 28 th day, 60 th day, and 90 th day. The erythrocyte incorporation rate in children was calculated using the stable isotope ratios, blood volume and body iron mass.Results The percentage of erythrocyte 57 Fe incorporation increased starting 14 th day, reached a peak at 60 d(boys: 19.67% ± 0.56%, girls: 21.33% ± 0.59%) and then decreased. The erythrocyte incorporation rates of 57 Fe obtained for girls in 60 th day was significantly higher than those obtained for boys(P < 0.0001).Conclusions The oral administration of 57 Fe to children can be used to obtain erythrocyte iron incorporation within 90 d. Prepubertal girls should begin to increase the intake of iron and further studies should pay more attention to the iron status in prepubertal children. 展开更多
关键词 Stable isotope tracer technique IRON Erythrocyte incorporation rate Beijing prepubertal children MC-ICP-MS
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N-Graphene Nanowalls via Plasma Nitrogen Incorporation and Substitution: The Experimental Evidence 被引量:1
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作者 Neelakandan MSanthosh Gregor Filipič +7 位作者 Eva Kovacevic Andrea Jagodar Johannes Berndt Thomas Strunskus Hiroki Kondo Masaru Hori Elena Tatarova UrošCvelbar 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第4期92-108,共17页
Incorporating nitrogen(N)atom in graphene is considered a key technique for tuning its electrical properties.However,this is still a great challenge,and it is unclear how to build N-graphene with desired nitrogen conf... Incorporating nitrogen(N)atom in graphene is considered a key technique for tuning its electrical properties.However,this is still a great challenge,and it is unclear how to build N-graphene with desired nitrogen configurations.There is a lack of experimental evidence to explain the influence and mechanism of structural defects for nitrogen incorporation into graphene compared to the derived DFT theories.Herein,this gap is bridged through a systematic study of different nitrogen-containing gaseous plasma post-treatments on graphene nanowalls(CNWs)to produce N-CNWs with incorporated and substituted nitrogen.The structural and morphological analyses describe a remarkable difference in the plasma–surface interaction,nitrogen concentration and nitrogen incorporation mechanism in CNWs by using different nitrogen-containing plasma.Electrical conductivity measurements revealed that the conductivity of the N-graphene is strongly influenced by the position and concentration of C–N bonding configurations.These findings open up a new pathway for the synthesis of N-graphene using plasma post-treatment to control the concentration and configuration of incorporated nitrogen for application-specific properties. 展开更多
关键词 GRAPHENE Graphene nanowalls Plasma post-treatment Nitrogen incorporation Raman spectroscopy Vacancy defects
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Detection of thiopurine s-methyltransferase mutations by template directed determinator in incorporation with fluorescence polarization (TDI-FP) 被引量:1
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作者 白玉杰 赵锦荣 +3 位作者 张文红 薛丽 郭晏海 闫小君 《Journal of Medical Colleges of PLA(China)》 CAS 2003年第6期F002-F002,392,393,共3页
Objective: To develop a new method for the detection of TPMT gene mutations and determine the frequencies of four TPMT alleles, TPMT *1, *3A , *3B and *3C in a healthy Chinese population. Methods: A TDI-FP assay syste... Objective: To develop a new method for the detection of TPMT gene mutations and determine the frequencies of four TPMT alleles, TPMT *1, *3A , *3B and *3C in a healthy Chinese population. Methods: A TDI-FP assay system was set up in out lab. To evaluate this system, 220 healthy individuals were analyzed for the polymorphic sites at positions 460(G→A)and 719(A→G)of the TPMP gene using our new TDI–FP method. Results: Three TPMP*3C(G 460→G 719) heterozygotes were identified, TPMP *3A and TPMP *3B were not found. All mutations were confirmed by conventional DNA sequencing analysis. Conclusion: TDI-FP method has proven to be very efficient as a rapid and accurate approach for TPMP genotyping. TPMP *3C was the only polymorphism identified in this clinical samples we have registered. 展开更多
关键词 thiopurine S-methyltransferase (TPMT) template- directed day-terminator incorporation (TDI) fluorescence polarization (FP) GENOTYPE polymorphism
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Effect of Incorporation of Chips and Wood Dust Mahogany on Mechanical and Acoustic Behavior of Brick Clay 被引量:1
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作者 Gilbert Ganga Timothee Nsongo +4 位作者 Hilaire Elenga Bernard Mabiala Thomas Tamo Tatsiete   Nzonzolo 《Journal of Building Construction and Planning Research》 2014年第3期198-208,共11页
An experimental study was carried out on bricks using local materials in order to take into account the waste wood management to protect the environment and to reduce the cost of the habitat. Chips and sawdust were bu... An experimental study was carried out on bricks using local materials in order to take into account the waste wood management to protect the environment and to reduce the cost of the habitat. Chips and sawdust were built-in clay bricks in order to study their influence on the compressive strength, Young’s modulus and the speed for soundproofing. Testings in compressive strength were made on the parallelepiped clay bricks, stabilized with different percentages of cement, with incorporation to various percentages of sawdust or wood chips (Mahogany), using a universal press. Young’s modulus was measured from the speed of sound by the ultrasonic method. The results obtained show that the incorporation of mahogany tree chips in the stabilized brick at 8% of cement, does not have much effect on the compressive strength. It was found that the incorporation of chips or sawdust on the clay brick, does not improve the compressive strength. The Young’s modulus decreases with increasing content of sawdust and practically remains constant regardless of the content of chips at 4% and 6% of cement. The clay brick mixed with 8% of mahogany sawdust can be an acoustic barrier. 展开更多
关键词 EFFECT of incorporation of CHIPS and Wood Dust MAHOGANY on MECHANICAL and Acoustic Behavior of BRICK CLAY
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SURFACE MODIFICATION OF PHOSPHOLIPID LIPOSOMES BY INCORPORATION OF GLYCOLIPID
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作者 Zi Chen LI Wei HE Fu Mian LI(Department of Chemistry, Peking Univerisity, Beijing 100871) 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第11期947-950,共4页
Two single-chain glycolipids, octadecyl-β-D-glucopyranoside(1) and 2-octadecanamido-2-deoxy-D-glucopyranose(2) were synthesized and their dispersing properties in water were studied. Incorporation of 1 into the phosp... Two single-chain glycolipids, octadecyl-β-D-glucopyranoside(1) and 2-octadecanamido-2-deoxy-D-glucopyranose(2) were synthesized and their dispersing properties in water were studied. Incorporation of 1 into the phospholipid liposomes could inhibit the aggregation of liposomes and improve the molecular packing in the bilayer membranes. 展开更多
关键词 SURFACE GLYCOLIPID incorporation LIPOSOMES MODIFICATION OF PHOSPHOLIPID BY
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