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9篇 您的检索式:作者名="Fengjiang LI"
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1The spatial pattern of farming and factors influencing it during the Peiligang culture period in the middle Yellow River valley, China显示文摘The Peiligang culture(ca.7000–5000 cal BC)is the earliest Neolithic culture in the middle Yellow River valley and represents the emergence of cereal farming in the region[1].It has long been considered representative of millet farming[2],which requires a dry field,a certain amount of rainfall,and minimal crop management,but new records reveal that mixed farming of millet and rice(Oryza sp.)took place during this period[3].Therefore,it is possibleCan Wang Houyuan Lu Wanfa Gu Naiqin Wu Jianping Zhang Xinxin Zuo Fengjiang Li Daojing Wang Yajie Dong Songzhi Wang Yanfeng Liu Yingjian Bao Yayi Hu 2017Science Bulletin2017,62,23:6
2Conductive photo-thermal responsive bifunctional hydrogel system with self-actuating and self-monitoring abilities显示文摘Despite enormous efforts in actuators,most researches are only limited to various actuation behaviors and demonstrations of soft materials.It has not yet been reported to capture and monitor its movement status in an invisible environment.Therefore,it is of great significance to develop a self-sensing and self-actuating dual-function hydrogel actuator system to realize real-time monitoring.Here,we report a bifunctional hydrogel system with self-actuating and self-monitoring abilities,which combines the functions of photothermal actuation and electrical resistance sensing into a single material.The bilayer tough conductive hydrogel synthesized by unconventional complementary concentration recombination and cryogenic freezing technique presents a dense conductive network and high-porosity structure,achieving high toughness at 190.3 kPa of tensile strength,high stretchability(164.3%strain),and the toughness dramatically(1,471.4 kJ·m^(−3)).The working mechanism of the monitoring and self-sensing system is accomplished through the integrated monitoring device of surface temperature–bending angle–electron current,to solve the problem of not apperceiving actuator motion state when encountering obstacles in an invisible environment.We demonstrated for the first time a photothermal actuator’s motion of a football player and goalkeeper to finish the penalty and a soft actuator hand,which can achieve the action of sticking to grab and release under photo-thermal actuation.When connected to the control closed circuit,the actuator realized closed-loop monitoring and sensing feedback.The development of bifunctional hydrogel systems may bring new opportunities and ideas in the fields of material science,circuit technology,sensors,and mechanical engineering.Neng Chen Yang Zhou Yinping Liu Yuanyuan Mi Sisi Zhao Wang Yang Sai Che Hongchen liu FengJiang Chen Chong Xu Guang Ma Xue Peng Yongfeng Li 2022Nano Research2022,15,8:3
3Generalized Switched-Capacitor Step-up Multilevel Inverter Employing Single DC Source显示文摘In this paper,a new generalized step-up multilevel DC-AC converter is proposed,which is suitable for applications with low-voltage input sources,such as photovoltaic power generation and electric vehicles.This inverter can achieve a high voltage gain by controlling the series-parallel conversion of the DC power supply and capacitors.Only one DC voltage source and a few power devices are employed.The maximum output voltage and the number of output levels can be further increased through the switched-capacitor unit’s extension and the submodule cascaded extension.Moreover,the capacitor voltages are self-balanced without complicated voltage control circuits.The complementary operating mechanism between each pair of switches simplifies the modulation algorithm.The inductiveload ability is fully taken into account in the proposed inverter.Additionally,a remarkable characteristic of the inverter is that the charging and discharging states among different capacitors are synchronous,which reduces the voltage ripple of the frontend capacitors.The circuit structure,the working principle,the modulation strategy,the capacitors and losses analysis are presented in detail.Afterwards,the advantages of the proposed inverter are analyzed by comparing with other recently proposed inverters.Finally,the steady-state and dynamic performance of the proposed inverter is verified and validated by simulation and experiment.Yaoqiang Wang Kaige Wang Gen Li Fengjiang Wu Kewen Wang Jun Liang 2022CSEE Journal of Power and Energy Systems2022,8,2:2
4Diffusion bonding of copper alloy to stainless steel with Ni and Cu interlayer 显示文摘 Wang Fengjiang Li Xiaoquan 2000Transactions of Nonferrous Metals Society of China (English Edition)2000,10,1:1
5Generation of high-energy narrowband 2.05 μm pulses for seeding a Ho:YLF laser显示文摘We experimentally demonstrate efficient generation of high-energy(82 μJ) narrowband 2.05 μm pulses pumped with 1 mJ broadband Ti:sapphire laser pulses, utilizing dual-chirped optical parametric amplification(DC-OPA)in a BBO crystal. The narrowband 2.05 μm pulses will be primarily used for seeding an Ho:YLF laser, which solves the synchronization issue when Ti:sapphire and Ho:YLF lasers are needed for developing midinfrared lasers. The narrowband 2.05 μm pulse from the unique DC-OPA design can seed the Ho:YLF laser much more efficiently than the broadband 2.05 μm pulse from traditional OPA technology.yanchun yin xiaoming ren yang wang fengjiang zhuang jie li zenghu chang 2018Photonics Research2018,9,1:0
6Bifunctional Mo-doped FeCo–Se aerogels catalysts with excellent OER and ORR activities for electro-Fenton process显示文摘Antibiotic pollution in aqueous solutions seriously endangers the natural environment and public health.In this work,Mo-doped transition metal FeCo–Se metal aerogels(MAs)were investigated as bifunctional catalysts for the removal of sulfamethazine(SMT)in solution.The optimal Mo_(0.3)Fe_(1)Co_(3)–Se catalyst can remove 97.7% of SMT within 60 min(SMT content:10 mg/L,current intensity:10 mA/cm 2).The unique porous cross-linked structure of aerogel confered the catalyst sufficient active sites and efficient mass transfer channels.For the anode,Mo_(0.3)Fe_(1)Co_(3)–Se MAs exhibits superior oxygen evolution reaction(OER)property,with an overpotential of only 235 mV(10 mA/cm 2).Compared with Fe_(1)Co_(3) MAs or Mo_(0.3)Fe_(1)Co_(3) MAs,density functional theory(DFT)demonstrated that the better catalytic capacity of Mo_(0.3)Fe_(1)Co_(3)–Se MAs is attributed to the doping of Mo species and selenization lowers the energy barrier for the*OOH to O_(2) step in the OER process.Excellent OER perfor-mance ensures the self-oxygenation in this system,avoiding the addition of air or oxygen in the traditional electro-Fenton process.For the cathode,Mo doping can lead to the lattice contraction and metallic character of CoSe_(2),which is beneficial to accelerate electron transfer.The adjacent Co active sites effectively adsorb*OOH and inhibit the breakage of the O–O bond.Rotating ring disk electrode(RRDE)test indicated that Mo_(0.3)Fe_(1)Co_(3)–Se MAs has an excellent 2e^(-)ORR activity with H_(2)O_(2) selectivity up to 88%,and the generated H_(2)O_(2) is activated by the adjacent Fe site through heterogeneous Fenton process to generate⋅OH.Fengjiang Chen Fan Yang Sai Che Hongchen Liu Chong Xu Neng Chen Yankun Sun Chunhui Yu Zhijie Wu Yongfeng Li 2023Green Chemical Engineering2023,4,3:0
7Forkhead box protein O1(FoxO1)regulates lipids metabolism and cell proliferation mediated by insulin and PI3K-Akt-mTOR pathway in goose primary hepatocytes显示文摘In order to explore the role of forkhead box protein O1(FoxO1)in the lipid metabolism and cell proliferation,goose primary hepatocytes were isolated and incubated with insulin or PI3K-Akt-mTOR pathway dual inhibitor NVPBEZ235,and then transfected with FoxO1 interference plasmid.The related parameters of lipid metabolism and cell proliferation were measured.The results firstly showed that FoxO1 interference increased the intracellular TG and lipids concentration(P<0.05);and increased the proliferative index(PI),cell DNA synthesis,protein expression of Cyclin D1 in goose primary hepatocytes(P<0.05).Secondly,the co-treatment of insulin and FoxO1 interference increased the mRNA level and protein content of Cyclin D1(P<0.05);however,there was no significant difference between the insulin treatment and the co-treatment of insulin and miR-FoxO1 interference in the intracellular TG and lipids concentration and PI(P>0.05).Lastly,the decrease of intracellular TG and lipids concentration and PI induced by NVP-BEZ235 was up-regulated by FoxO1 interference significantly(P<0.05).In summary,FoxO1 could regulate the lipids metabolism and cell proliferation mediated by PI3K-Akt-mTOR signaling pathway in goose primary hepatocytes.Further investigations are required to highlight the potential role of FoxO1 in the lipid metabolism and cell proliferation mediated by insulin in goose primary hepatocyte.RONGXUE WEI CHUNCHUN HAN FENGJIANG YE SHOUHAI WEI FANG HE HEHE LIU LIANG LI HONGYONG XU SHENQIANG HU XIANYIN ZENG 2022BIOCELL2022,46,1:0
8Eco-environmental changes in the Chinese Loess Plateau during low-eccentricity interglacial Marine Isotope Stage 19显示文摘Eco-environmental changes during interglacials with an astronomical background similar to that of the Holocene are potentially helpful for understanding the future climatic evolution.Marine oxygen isotope stage(MIS)19 is similar to the Holocene in astronomical background,both being characterized by a low eccentricity of the Earth’s orbit.However,MIS 19 has attracted research attention only recently and therefore less is known about eco-environmental changes during this interval,especially based on terrestrial records.In the Chinese Loess Plateau(CLP),the S7 paleosol can provide valuable terrestrial paleoclimatic and paleoenvironmental record for MIS 19.Here,high-resolution terrestrial snail records from the L8–L7 strata of the Huining,Xifeng and Luochuan sequences in the CLP were analyzed in order to characterize spatio-temporal changes in climate and eco-environment during MIS 20–18.The results show that in all three sections the late part of MIS 20 was dominated by abundant cold-aridiphilous mollusc species,indicating that cold and dry climatic conditions prevailed across the entire CLP,under the strong influence of the winter monsoon.The mollusc fauna of MIS 19 were dominated by warmth-loving and thermohumidiphilous species that enable the definition of two climatic stages.The early part of MIS 19(~790–778 ka)was marked by warm and humid conditions,as evidenced by high abundances of warmth-loving and thermo-humidiphilous species.This interval was slightly warmer than today and it lasted for^12 kyr.The climate of the later part of MIS 19(~778–761 ka)was more moderate,and increased proportions of cold-aridiphilous and warmth-loving species were recorded.The warmth of this period was similar to that of today,but the climatic fluctuations were stronger.During the early part of MIS 18(~761–745 ka),the Xifeng and Luochuan sections in the eastern CLP still maintained high abundances of warmth-loving and thermo-humidiphilous species,indicating that the moderate climatic conditions during late MIS 19 continued during early MIS 18,lasting for another^15 kyr,and that the influence of the summer monsoon remained strong in the eastern CLP during early MIS 18.However,in the western CLP,cold-aridiphilous species in the Huining section became dominant during early MIS 18,reflecting the prevalence of a cold and dry glacial climate,with the strong influence of the winter monsoon.These findings indicate that a steeper climatic gradient and a pronounced regional environmental difference existed between the eastern and western CLP during the early part of MIS 18.Comparison of our mollusc results with the variation of Earth orbital parameters suggested that climate changes in the CLP during MIS 20–18 were likely controlled mainly by insolation changes forced by the configuration of Earth orbital parameters.The unique orbital configuration during the low eccentricity interglacial-to-glacial transition could have strengthened the East Asian summer monsoon which favored the amelioration of the eco-environment in the CLP,especially in the eastern CLP where the summer monsoon exerted a strong influence.Thus we speculate that,under natural climatic conditions,the climate of the CLP may remain in a warm,humid state for another 30 kyr,although climatic instability and the seasonal differences between winter and summer could strengthen.Yueting ZHANG Naiqin WU Fengjiang LI Qingzhen HAO Yajie DONG Dan ZHANG Houyuan LU 2020Science China Earth Sciences2020,63,9:0
9Effects of Enclosure on Grassland Ecological and Economic Benefits in Northern China显示文摘Grasslands in northern China serve the country as both an ecological barrier and a livestock production base.There,installing enclosures has been becoming the major grassland restoration measure adopted by many local governments.However,the effects of restoration on both ecological and production benefits of grassland remain unclear for implemented grassland restoration policies.Therefore,a representative rangeland in northern China,the Maodeng pasture in Inner Mongolia Autonomous Region was selected as the study area,and remote sensing monitoring analyses were carried out to quantify the ecological benefits and economic benefits from 2015 to 2021.The results showed that:1) in terms of ecological benefits,the grassland area with a grassland coverage rate of more than 60% accounts for 32.3% of the regional area,and 86.4% of its grassland grew significantly better than the same period in2015,showing a significant improvement in grassland growth.Using the average amount of carbon per unit area as the ecological benefit evaluation index,it increased by 27.1% to 32.48Tg C/yr from 2015 to 2021.2) In terms of economic benefits,both theoretical grass production and livestock carrying capacity increased from 2015 to 2021.Compared to 2015,the theoretical grass production in 2021 increased by 24.8% to 71 900 t.The livestock carrying capacity reached 52 100 sheep units in 2021,nearly 11 000 sheep units more than that in 2015.During the study period,multiple economic indicators(on a per capita basis of permanent residents) for the pastoral area of Xilinhot City to which the Maodeng pasture belongs,have grown steadily.Per capita total income rose from 29 630 yuan(RMB) in2015 to 62 859 yuan(RMB) in 2021.Relying on grassland resources to develop the pastoral ecology also broadens the potential economic development space.Overall,the establishment of the reserve and the experiment of implanting an enclosure policy have had a significant and positive impact on Maodeng pasture’s development from both an ecological and economic perspective.With the support of scientific evidence,enclosure policy can be extended to more than 110 000 km~2 of grasslands in northern China with similar precipitation and temperature conditions,enhancing the productive and ecological potential of grasslands.The above research results will contribute to the scientific formulation of grassland pasture quality improvement plans in northern China.HU Bo WEN Qingke XI Fengjiang LI Mengyao WANG Libing REN Yuejuan 2024Chinese Geographical Science2024,34,1:0
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