Protoplasts derived from common wheat (Triticum aestivum L,. cv. Jinan 177) were fused with UV-treated protoplasts of Agropyron elongatum. (Host) Nevski by PEG method, and fertile asymmetric somatic hybrid plants rese...Protoplasts derived from common wheat (Triticum aestivum L,. cv. Jinan 177) were fused with UV-treated protoplasts of Agropyron elongatum. (Host) Nevski by PEG method, and fertile asymmetric somatic hybrid plants resembling wheat morphology were obtained. The F-2 hybrid plants could be divided into 3 types according to their morphology. Type I hybrids had high and loosely standing stalks with big spikes and grains. Type ii hybrids were dwarf and compact in shape with high tillering ability and smaller spikes. Type III hybrids were similar to type I as a whole but had more compact and erect spikes. All the F-2 hybrid lines were superior to wheat in seed protein content, although some difference existed between themselves. Protein analysis of immature embryos and flag leaves from hybrids by two-dimensional electrophoresis showed that they possessed characteristic proteins of both parents and some new proteins. There existed also some different kinds of proteins in different lines.展开更多
Magnesium ion batteries(MIBs)are a potential field for the energy storage of the future but are restricted by insufficient rate capability and rapid capacity degradation.Magnesium-sodium hybrid ion batteries(MSHBs)are...Magnesium ion batteries(MIBs)are a potential field for the energy storage of the future but are restricted by insufficient rate capability and rapid capacity degradation.Magnesium-sodium hybrid ion batteries(MSHBs)are an effective way to address these problems.Here,we report a new type of MSHBs that use layered sodium vanadate((Na,Mn)V_(8)O_(20)·5H_(2)O,Mn-NVO)cathodes coupled with an organic 3,4,9,10-perylenetetracarboxylic diimide(PTCDI)anode in Mg^(2+)/Na^(+)hybrid electrolytes.During electrochemical cycling,Mg^(2+)and Na^(+)co-participate in the cathode reactions,and the introduction of Na^(+)promotes the structural stability of the Mn-NVO cathode,as cleared by several ex-situ characterizations.Consequently,the Mn-NVO cathode presents great specific capacity(249.9 mA h g^(−1)at 300 mA g^(−1))and cycling(1500 cycles at 1500 mA g^(−1))in the Mg^(2+)/Na^(+)hybrid electrolytes.Besides,full battery displays long lifespan with 10,000 cycles at 1000 mA g^(−1).The rate performance and cycling stability of MSHBs have been improved by an economical and scalable method,and the mechanism for these improvements is discussed.展开更多
Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realiz...Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realized the defect regulation of crystal NiCo_(2)S_(4) in the core.Taking advantage of the flexible protection of an amor-phous shell and the high capacity of a conductive core with defects,the v-NCS@MS electrode exhibited high specif-ic capacity(1034 mAh·g^(-1) at 1 A·g^(-1))and outstanding rate capability.Moreover,a hybrid supercapacitor was assembled with v-NCS@MS as cathode and activated carbon(AC)as anode,which can achieve remarkably high specific energy of 111 Wh·kg^(-1) at a specific power of 219 W·kg^(-1) and outstanding capacity retention of 80.5%after 15000 cycling at different current densities.展开更多
Renewable energy driven N_(2) electroreduction with air as nitrogen source holds great promise for realizing scalable green ammonia production.However,relevant out-lab research is still in its infancy.Herein,a novel S...Renewable energy driven N_(2) electroreduction with air as nitrogen source holds great promise for realizing scalable green ammonia production.However,relevant out-lab research is still in its infancy.Herein,a novel Sn-based MXene/MAX hybrid with abundant Sn vacancies,Sn@Ti_(2)CTX/Ti_(2)SnC–V,was synthesized by controlled etching Sn@Ti_(2)SnC MAX phase and demonstrated as an efficient electrocatalyst for electrocatalytic N2 reduction.Due to the synergistic effect of MXene/MAX heterostructure,the existence of Sn vacancies and the highly dispersed Sn active sites,the obtained Sn@Ti2CTX/Ti_(2)SnC–V exhibits an optimal NH_(3) yield of 28.4μg h^(−1) mg_(cat)^(−1) with an excellent FE of 15.57% at−0.4 V versus reversible hydrogen electrode in 0.1 M Na_(2)SO_(4),as well as an ultra-long durability.Noticeably,this catalyst represents a satisfactory NH3 yield rate of 10.53μg h^(−1) mg^(−1) in the home-made simulation device,where commercial electrochemical photovoltaic cell was employed as power source,air and ultrapure water as feed stock.The as-proposed strategy represents great potential toward ammonia production in terms of financial cost according to the systematic technical economic analysis.This work is of significance for large-scale green ammonia production.展开更多
The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in orde...The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in order to provide ultimate wear resistance based on the laser-irradiation-induced inclusion of N_(2) gas during laser powder bed fusion.This is substantialized based on both the thermal diffusion-and chemical reactionbased metallurgy of the Mg_(2)Si–SiC/nitride hybrid composite.This study also proposes a functional platform for systematically modulating a functionally graded structure and modeling build-direction-dependent architectonics during additive manufacturing.This strategy enables the development of a compositional gradient from the center to the edge of each melt pool of the Mg_(2)Si–SiC/nitride hybrid composite.Consequently,the coefficient of friction of the hybrid composite exhibits a 309.3%decrease to–1.67 compared to–0.54 for the conventional nonreinforced Mg_(2)Si structure,while the tensile strength exhibits a 171.3%increase to 831.5 MPa compared to 485.3 MPa for the conventional structure.This outstanding mechanical behavior is due to the(1)the complementary and synergistic reinforcement effects of the SiC and nitride compounds,each of which possesses an intrinsically high hardness,and(2)the strong adhesion of these compounds to the Mg_(2)Si matrix despite their small sizes and low concentrations.展开更多
We compared the photosynthetic characteristics in relation to yield of two F1 cotton hybrids(Shiza 2-F1 and Xinluzao 43-F1), their parental lines(NT2, H2 and 4-14) and their F2 descendants at different growth and ...We compared the photosynthetic characteristics in relation to yield of two F1 cotton hybrids(Shiza 2-F1 and Xinluzao 43-F1), their parental lines(NT2, H2 and 4-14) and their F2 descendants at different growth and development stages. The two F1 exhibited heterobeltiosis in net photosynthetic rate(Pn) by 8.1-52.1%, canopy apparent photosynthetic rate(CAP) by 8.2-57.6% and canopy respiration rate(CR) by 3.0-78.7% during the growing season. They also exhibited mid-parent heterosis by 2.0-5.2% in leaf chlorophyll content(SPAD) during the late growth and development stages. Regression analysis showed that both parents contributed to increase in Pn, SPAD and CAP in the F1. A low CR in the F1 matched a low CR of the parental line. Photosynthetic characteristics in the F2 were mainly dependent upon the magnitude and degeneration rate of the F1. Mid-parent heterosis in CAP and in CR during the late growth and development stage reduced the degeneration of the F2. Average dry matter accumulation was 10.7-34.7% higher in the parental lines of Xinluzao 43-F1 than in the parental lines of Shiza 2-F1. Heterobeltiosis in dry matter accumulation was 7.0-23.1% greater for Xinluzao 43-F1 than for Shiza 2-F1. Dry matter accumulation in the F1 was affected by either the dry matter accumulation of parents or heterobeltiosis. Dry matter accumulation in the F2 was mainly influenced by dry matter accumulation in the F1. The yields of the two F1 were 39.1-46.3% higher than their respective parents and 26.4-45.9% higher than that of the conventional cultivar Xinluzao 33. The yields of the two F2 were 9.2-12.8% higher than the parents and 14.9-27.4% higher than that of Xinluzao 33. The photosynthetic production and yield of the F1 and F2 were higher than that of their parents. The increases in Pn and CAP of the F1 and F2 were dependent on the photosynthetic characteristics of their parents. It is thus concluded that the photosynthetic performance, light use efficiency and yield of the F1 can be improved by using at least one parent with low CR, but high CAP, Pn and SPAD. This strategy might also improve the value of the F2.展开更多
Electrochemical reduction of Bi-based metal oxides is regarded as an effective strategy to rationally design advanced electrocatalysts for electrochemical CO_(2)reduction reaction(CO_(2)RR).Realizing high selectivity ...Electrochemical reduction of Bi-based metal oxides is regarded as an effective strategy to rationally design advanced electrocatalysts for electrochemical CO_(2)reduction reaction(CO_(2)RR).Realizing high selectivity at high current density is important for formate production,but remains challenging.Herein,the BiIn hybrid electrocatalyst,deriving from the Bi2O3/In2O3heterojunction(MOD-Biln),shows excellent catalytic performance for CO_(2)RR.The Faradaic efficiency of formate(FEHCOO-) can be realized over 90% at a wide potential window from-0.4 to-1.4 V vs.RHE,while the partial current density of formate(jHCOO-) reaches about 136.7 mA cm^(-2)at-1.4 V in flow cell without IR-compensation.In additio n,the MOD-Biln exhibits superior stability with high selectivity of formate at 100 mA cm^(-2).Systematic characterizations prove the optimized catalytic sites and interface charge transfer of MOD-Biln,while theoretical calculation confirms that the hybrid structure with dual Bi/In metal sites contribute to the optimal free energy of*H and*OCHO intermediates on MOD-Biln surface,thus accelerating the formation and desorption step of*HCOOH to final formate production.Our work provides a facile and useful strategy to develop highly-active and stable electrocatalysts for CO_(2)RR.展开更多
The development of low-cost,robust and efficient non-noble metal electrocatalysts is still a pursuit for the hydrogen evolution reaction(HER).Herein,a self-standing electrocatalyst,Ni_(2)P/CoP nanosheet,was fabricated...The development of low-cost,robust and efficient non-noble metal electrocatalysts is still a pursuit for the hydrogen evolution reaction(HER).Herein,a self-standing electrocatalyst,Ni_(2)P/CoP nanosheet,was fabricated directly on three-dimensional Ni foams by two facile steps,which illustrated both high activity and stability for HER in different electrolytes.Benefiting from the porous structures of nanosheets with large specific surface area and the hybrid Ni_(2)P/CoP,the as-prepared electrocatalyst presented remarkable HER with overpotentials of 65.2 and 87.8 mV to reach a current density of-10 mA cm^(-2)in neutral and alkaline media,respectively.Density function theory calculations revealed a lower activation energy of water dissociation and efficient HER steps of hybrid Ni_(2)P/CoP nanosheets compared with mono CoP.The self-standing electrocatalyst maintained excellent chemical stability.Additionally,the HER process in domestic wastewater was realized with more impressive performance by using Ni_(2)P/CoP nanosheets compared with commercial Pt/C.Hydrogen was continuously generated for 20 h in mildly alkaline dishwashing wastewater.This work provides a feasible way to fabricate non-noble metal and self-standing hybrid bimetallic phosphides for HER in neutral and alkaline media,showing great potential for efficient hydrogen production by re-utilizing wastewater resources.展开更多
Together with the development of high-performance advanced electronics,flexible supercapacitors(SCs)with tailored nanostructures have great attraction.Electrochemically deposited nanosheet arrays of nickel magnesium s...Together with the development of high-performance advanced electronics,flexible supercapacitors(SCs)with tailored nanostructures have great attraction.Electrochemically deposited nanosheet arrays of nickel magnesium selenide(NixMg3-xSe4,NMgS)with high capacitance provide high potentials as a positive electrode in flexible SCs.To further enhance their electrochemical properties and long-term cycling stability,a promising strategy of surface engineering with conducting polymer poly(3,4-ethylenedioxythiophene)(PEDOT)is proposed.The present work proposes the construction of PEDOT shielded NMgS(P@NMgS-2)on a flexible carbon cloth substrate via a hierarchical electrodeposition technique.Benefitting from the synergistic effect,the P@NMgS-2 exhibits an excellent areal capacitance value of 1440 mF cm^(-2)at 4 mA cm^(-2).A novel shape-adaptable polymer gel electrolyte-assisted flexible quasi-solid-state hybrid SC(FQHSC)device constructed with P@NMgS-2 as a positive electrode and activated carbon as a negative electrode demonstrates the maximum power and energy density values of 14.13 mW cm^(-2)and 0.18 mWh cm^(-2),respectively,followed by outstanding cycling stability(∼100%capacitance retention over 50,000 cycles).Furthermore,the FQHSC device successfully powered electronic devices with no serious degradation upon bending and twisting for wearable electronic applications.展开更多
In this work,a two-dimensional hybrid model,which consists of a bulk fluid module,a sheath module and an ion Monte-Carlo module,is developed to investigate the modulation of ion energy and angular distributions at dif...In this work,a two-dimensional hybrid model,which consists of a bulk fluid module,a sheath module and an ion Monte-Carlo module,is developed to investigate the modulation of ion energy and angular distributions at different radial positions in a biased argon inductively coupled plasma.The results indicate that when the bias voltage amplitude increases or the bias frequency decreases,the ion energy peak separation width becomes wider.Besides,the widths of the ion energy peaks at the edge of the substrate are smaller than those at the center due to the lower plasma density there,indicating the nonuniformity of the ion energy distribution function(IEDF)along the radial direction.As the pressure increases from 1 to 10 Pa,the discrepancy of the IEDFs at different radial positions becomes more obvious,i.e.the IEDF at the radial edge is characterized by multiple low energy peaks.When a dual frequency bias source is applied,the IEDF exhibits three or four peaks,and it could be modulated efficiently by the relative phase between the two bias frequencies.The results obtained in this work could help to improve the radial uniformity of the IEDF and thus the etching process.展开更多
A hybrid heat pump(compression/absorption)with an integrated thermal photovoltaic unit is studied.The considered working fluids are organic mixtures:R245fa/DMAC and R236fa/DMAC,chosen for their low Global Warming Pote...A hybrid heat pump(compression/absorption)with an integrated thermal photovoltaic unit is studied.The considered working fluids are organic mixtures:R245fa/DMAC and R236fa/DMAC,chosen for their low Global Warming Potential.The main objective is the optimization of energy efficiency in order to minimize the environmental impact through the implementation of a sustainable strategy.It is shown that Exergy Analysis itself is a valuable tool in energy integration.Within the imposed framework of minimizing total annual costs,entropy analysis can be instrumental in determining the optimal plant concept,optimizing energy conversion and use,and improving profitability.The present results are discussed under the optimistic hope that they may help to define new energy and environmental policies.展开更多
Many plant species have a startling degree of morphological similarity,making it difficult to split and categorize them reliably.Unknown plant species can be challenging to classify and segment using deep learning.Whi...Many plant species have a startling degree of morphological similarity,making it difficult to split and categorize them reliably.Unknown plant species can be challenging to classify and segment using deep learning.While using deep learning architectures has helped improve classification accuracy,the resulting models often need to be more flexible and require a large dataset to train.For the sake of taxonomy,this research proposes a hybrid method for categorizing guava,potato,and java plumleaves.Two new approaches are used to formthe hybridmodel suggested here.The guava,potato,and java plum plant species have been successfully segmented using the first model built on the MobileNetV2-UNET architecture.As a second model,we use a Plant Species Detection Stacking Ensemble Deep Learning Model(PSD-SE-DLM)to identify potatoes,java plums,and guava.The proposed models were trained using data collected in Punjab,Pakistan,consisting of images of healthy and sick leaves from guava,java plum,and potatoes.These datasets are known as PLSD and PLSSD.Accuracy levels of 99.84%and 96.38%were achieved for the suggested PSD-SE-DLM and MobileNetV2-UNET models,respectively.展开更多
Multilevel phase-change memory is an attractive technology to increase storage capacity and density owing to its high-speed,scalable and non-volatile characteristics.However,the contradiction between thermal stability...Multilevel phase-change memory is an attractive technology to increase storage capacity and density owing to its high-speed,scalable and non-volatile characteristics.However,the contradiction between thermal stability and operation speed is one of key factors to restrain the development of phase-change memory.Here,N-doped Ge_(2)Sb_(2)Te_(5)-based optoelectronic hybrid memory is proposed to simultaneously implement high thermal stability and ultrafast operation speed.The picosecond laser is adopted to write/erase information based on reversible phase transition characteristics whereas the resistance is detected to perform information readout.Results show that when N content is 27.4 at.%,N-doped Ge_(2)Sb_(2)Te_(5)film possesses high ten-year data retention temperature of 175℃and low resistance drift coefficient of 0.00024 at 85℃,0.00170 at 120℃,and 0.00249 at 150℃,respectively,owing to the formation of Ge–N,Sb–N,and Te–N bonds.The SET/RESET operation speeds of the film reach 520 ps/13 ps.In parallel,the reversible switching cycle of the corresponding device is realized with the resistance ratio of three orders of magnitude.Four-level reversible resistance states induced by various crystallization degrees are also obtained together with low resistance drift coefficients.Therefore,the N-doped Ge_(2)Sb_(2)Te_(5)thin film is a promising phase-change material for ultrafast multilevel optoelectronic hybrid storage.展开更多
文摘Protoplasts derived from common wheat (Triticum aestivum L,. cv. Jinan 177) were fused with UV-treated protoplasts of Agropyron elongatum. (Host) Nevski by PEG method, and fertile asymmetric somatic hybrid plants resembling wheat morphology were obtained. The F-2 hybrid plants could be divided into 3 types according to their morphology. Type I hybrids had high and loosely standing stalks with big spikes and grains. Type ii hybrids were dwarf and compact in shape with high tillering ability and smaller spikes. Type III hybrids were similar to type I as a whole but had more compact and erect spikes. All the F-2 hybrid lines were superior to wheat in seed protein content, although some difference existed between themselves. Protein analysis of immature embryos and flag leaves from hybrids by two-dimensional electrophoresis showed that they possessed characteristic proteins of both parents and some new proteins. There existed also some different kinds of proteins in different lines.
基金the financial support from the National Natural Science Foundation of China, China (22005207, 52261160384)the Guangdong Basic and Applied Basic Research Foundation, Guangdong Province, China (2019A1515011819)+2 种基金the Outstanding Youth Basic Research Project of Shenzhen, Shenzhen, China (RCYX20221008092934093)the Joint Funds of the National Natural Science Foundation of China, China (U22A20140)the Science and Technology Development Fund, Macao SAR (0090/2021/A2 and 0049/2021/AGJ)
文摘Magnesium ion batteries(MIBs)are a potential field for the energy storage of the future but are restricted by insufficient rate capability and rapid capacity degradation.Magnesium-sodium hybrid ion batteries(MSHBs)are an effective way to address these problems.Here,we report a new type of MSHBs that use layered sodium vanadate((Na,Mn)V_(8)O_(20)·5H_(2)O,Mn-NVO)cathodes coupled with an organic 3,4,9,10-perylenetetracarboxylic diimide(PTCDI)anode in Mg^(2+)/Na^(+)hybrid electrolytes.During electrochemical cycling,Mg^(2+)and Na^(+)co-participate in the cathode reactions,and the introduction of Na^(+)promotes the structural stability of the Mn-NVO cathode,as cleared by several ex-situ characterizations.Consequently,the Mn-NVO cathode presents great specific capacity(249.9 mA h g^(−1)at 300 mA g^(−1))and cycling(1500 cycles at 1500 mA g^(−1))in the Mg^(2+)/Na^(+)hybrid electrolytes.Besides,full battery displays long lifespan with 10,000 cycles at 1000 mA g^(−1).The rate performance and cycling stability of MSHBs have been improved by an economical and scalable method,and the mechanism for these improvements is discussed.
文摘Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realized the defect regulation of crystal NiCo_(2)S_(4) in the core.Taking advantage of the flexible protection of an amor-phous shell and the high capacity of a conductive core with defects,the v-NCS@MS electrode exhibited high specif-ic capacity(1034 mAh·g^(-1) at 1 A·g^(-1))and outstanding rate capability.Moreover,a hybrid supercapacitor was assembled with v-NCS@MS as cathode and activated carbon(AC)as anode,which can achieve remarkably high specific energy of 111 Wh·kg^(-1) at a specific power of 219 W·kg^(-1) and outstanding capacity retention of 80.5%after 15000 cycling at different current densities.
基金This work was supported by the National Natural Science Foundation of China(Nos.22308139,52071171,52202248)Natural Science Foundation of Liaoning Province(2023-MS-140)+11 种基金Liaoning BaiQianWan Talents Program(LNBQW2018B0048)Shenyang Science and Technology Project(21-108-9-04)Young Scientific and Technological Talents Project of the Department of Education of Liaoning Province(LQN202008)Key Research Project of Department of Education of Liaoning Province(LJKZZ20220015)Foundation of State Key Laboratory of Clean and Efficient Coal Utilization,Taiyuan University of Technology(MJNYSKL202301)Foundation of State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering(KF2023006)Anhui Province Key Laboratory of Coal Clean Conversion and High Valued Utilization,Anhui University of Technology(CHV22-05)Australian Research Council(ARC)through Future Fellowship(FT210100298,FT210100806)Discovery Project(DP220100603)Linkage Project(LP210100467,LP210200504,LP210200345,LP220100088)Industrial Transformation Training Centre(IC180100005)schemesthe Australian Government through the Cooperative Research Centres Projects(CRCPXIII000077).
文摘Renewable energy driven N_(2) electroreduction with air as nitrogen source holds great promise for realizing scalable green ammonia production.However,relevant out-lab research is still in its infancy.Herein,a novel Sn-based MXene/MAX hybrid with abundant Sn vacancies,Sn@Ti_(2)CTX/Ti_(2)SnC–V,was synthesized by controlled etching Sn@Ti_(2)SnC MAX phase and demonstrated as an efficient electrocatalyst for electrocatalytic N2 reduction.Due to the synergistic effect of MXene/MAX heterostructure,the existence of Sn vacancies and the highly dispersed Sn active sites,the obtained Sn@Ti2CTX/Ti_(2)SnC–V exhibits an optimal NH_(3) yield of 28.4μg h^(−1) mg_(cat)^(−1) with an excellent FE of 15.57% at−0.4 V versus reversible hydrogen electrode in 0.1 M Na_(2)SO_(4),as well as an ultra-long durability.Noticeably,this catalyst represents a satisfactory NH3 yield rate of 10.53μg h^(−1) mg^(−1) in the home-made simulation device,where commercial electrochemical photovoltaic cell was employed as power source,air and ultrapure water as feed stock.The as-proposed strategy represents great potential toward ammonia production in terms of financial cost according to the systematic technical economic analysis.This work is of significance for large-scale green ammonia production.
基金supported by the Learning & Academic Research Institution for Master’s and Ph.D. Students and Postdocs (LAMP) Program of the National Research Foundation of Korea (NRF) grant funded by the Ministry of Education (No. RS-2023-00285353)supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) (NRF-2021R1A2C3006662, NRF-2022R1A5A1030054, and 2021R1A2C1091301)+3 种基金the support from Natural Sciences and Engineering Research Council of Canada (NSERC)Canada Foundation for Innovation (CFI)Atlantic Canada Opportunities Agency (ACOA)the New Brunswick Innovation Foundation (NBIF)
文摘The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in order to provide ultimate wear resistance based on the laser-irradiation-induced inclusion of N_(2) gas during laser powder bed fusion.This is substantialized based on both the thermal diffusion-and chemical reactionbased metallurgy of the Mg_(2)Si–SiC/nitride hybrid composite.This study also proposes a functional platform for systematically modulating a functionally graded structure and modeling build-direction-dependent architectonics during additive manufacturing.This strategy enables the development of a compositional gradient from the center to the edge of each melt pool of the Mg_(2)Si–SiC/nitride hybrid composite.Consequently,the coefficient of friction of the hybrid composite exhibits a 309.3%decrease to–1.67 compared to–0.54 for the conventional nonreinforced Mg_(2)Si structure,while the tensile strength exhibits a 171.3%increase to 831.5 MPa compared to 485.3 MPa for the conventional structure.This outstanding mechanical behavior is due to the(1)the complementary and synergistic reinforcement effects of the SiC and nitride compounds,each of which possesses an intrinsically high hardness,and(2)the strong adhesion of these compounds to the Mg_(2)Si matrix despite their small sizes and low concentrations.
基金the National Natural Science Foundation of China(U1203283,31060176)the Key Technologies R&D Program of China during the 11th Five-Year Plan period(2007BAD44B07)
文摘We compared the photosynthetic characteristics in relation to yield of two F1 cotton hybrids(Shiza 2-F1 and Xinluzao 43-F1), their parental lines(NT2, H2 and 4-14) and their F2 descendants at different growth and development stages. The two F1 exhibited heterobeltiosis in net photosynthetic rate(Pn) by 8.1-52.1%, canopy apparent photosynthetic rate(CAP) by 8.2-57.6% and canopy respiration rate(CR) by 3.0-78.7% during the growing season. They also exhibited mid-parent heterosis by 2.0-5.2% in leaf chlorophyll content(SPAD) during the late growth and development stages. Regression analysis showed that both parents contributed to increase in Pn, SPAD and CAP in the F1. A low CR in the F1 matched a low CR of the parental line. Photosynthetic characteristics in the F2 were mainly dependent upon the magnitude and degeneration rate of the F1. Mid-parent heterosis in CAP and in CR during the late growth and development stage reduced the degeneration of the F2. Average dry matter accumulation was 10.7-34.7% higher in the parental lines of Xinluzao 43-F1 than in the parental lines of Shiza 2-F1. Heterobeltiosis in dry matter accumulation was 7.0-23.1% greater for Xinluzao 43-F1 than for Shiza 2-F1. Dry matter accumulation in the F1 was affected by either the dry matter accumulation of parents or heterobeltiosis. Dry matter accumulation in the F2 was mainly influenced by dry matter accumulation in the F1. The yields of the two F1 were 39.1-46.3% higher than their respective parents and 26.4-45.9% higher than that of the conventional cultivar Xinluzao 33. The yields of the two F2 were 9.2-12.8% higher than the parents and 14.9-27.4% higher than that of Xinluzao 33. The photosynthetic production and yield of the F1 and F2 were higher than that of their parents. The increases in Pn and CAP of the F1 and F2 were dependent on the photosynthetic characteristics of their parents. It is thus concluded that the photosynthetic performance, light use efficiency and yield of the F1 can be improved by using at least one parent with low CR, but high CAP, Pn and SPAD. This strategy might also improve the value of the F2.
基金financially supported by the National Natural Science Foundation of China (Grant Nos. 22205205)the Zhejiang Provincial Natural Science Foundation of China (Grant Nos.LQ22B030008)the Science Foundation of Zhejiang Sci-Tech University (ZSTU)(Grant Nos. 21062337-Y and 22062312-Y)。
文摘Electrochemical reduction of Bi-based metal oxides is regarded as an effective strategy to rationally design advanced electrocatalysts for electrochemical CO_(2)reduction reaction(CO_(2)RR).Realizing high selectivity at high current density is important for formate production,but remains challenging.Herein,the BiIn hybrid electrocatalyst,deriving from the Bi2O3/In2O3heterojunction(MOD-Biln),shows excellent catalytic performance for CO_(2)RR.The Faradaic efficiency of formate(FEHCOO-) can be realized over 90% at a wide potential window from-0.4 to-1.4 V vs.RHE,while the partial current density of formate(jHCOO-) reaches about 136.7 mA cm^(-2)at-1.4 V in flow cell without IR-compensation.In additio n,the MOD-Biln exhibits superior stability with high selectivity of formate at 100 mA cm^(-2).Systematic characterizations prove the optimized catalytic sites and interface charge transfer of MOD-Biln,while theoretical calculation confirms that the hybrid structure with dual Bi/In metal sites contribute to the optimal free energy of*H and*OCHO intermediates on MOD-Biln surface,thus accelerating the formation and desorption step of*HCOOH to final formate production.Our work provides a facile and useful strategy to develop highly-active and stable electrocatalysts for CO_(2)RR.
基金China Scholarship Council/University College London for joint PhD scholarships,Engineering and Physical Sciences Research Council(EPSRC,EP/V027433/1,EP/L015862/1,EP/R023581/1)supported by the Royal Academy of Engineering under the Research Chairs and Senior Research Fellowships scheme(Brett and Shearing)the Royal Society(RGS\R1\211080,IEC\NSFC\201261)for funding support.
文摘The development of low-cost,robust and efficient non-noble metal electrocatalysts is still a pursuit for the hydrogen evolution reaction(HER).Herein,a self-standing electrocatalyst,Ni_(2)P/CoP nanosheet,was fabricated directly on three-dimensional Ni foams by two facile steps,which illustrated both high activity and stability for HER in different electrolytes.Benefiting from the porous structures of nanosheets with large specific surface area and the hybrid Ni_(2)P/CoP,the as-prepared electrocatalyst presented remarkable HER with overpotentials of 65.2 and 87.8 mV to reach a current density of-10 mA cm^(-2)in neutral and alkaline media,respectively.Density function theory calculations revealed a lower activation energy of water dissociation and efficient HER steps of hybrid Ni_(2)P/CoP nanosheets compared with mono CoP.The self-standing electrocatalyst maintained excellent chemical stability.Additionally,the HER process in domestic wastewater was realized with more impressive performance by using Ni_(2)P/CoP nanosheets compared with commercial Pt/C.Hydrogen was continuously generated for 20 h in mildly alkaline dishwashing wastewater.This work provides a feasible way to fabricate non-noble metal and self-standing hybrid bimetallic phosphides for HER in neutral and alkaline media,showing great potential for efficient hydrogen production by re-utilizing wastewater resources.
基金This work was supported by the National Research Foundation of Korea Grant funded by the Korea government(MSIP)(No.2018R1A6A1A03025708 and No.2020R1A2B5B01002318).
文摘Together with the development of high-performance advanced electronics,flexible supercapacitors(SCs)with tailored nanostructures have great attraction.Electrochemically deposited nanosheet arrays of nickel magnesium selenide(NixMg3-xSe4,NMgS)with high capacitance provide high potentials as a positive electrode in flexible SCs.To further enhance their electrochemical properties and long-term cycling stability,a promising strategy of surface engineering with conducting polymer poly(3,4-ethylenedioxythiophene)(PEDOT)is proposed.The present work proposes the construction of PEDOT shielded NMgS(P@NMgS-2)on a flexible carbon cloth substrate via a hierarchical electrodeposition technique.Benefitting from the synergistic effect,the P@NMgS-2 exhibits an excellent areal capacitance value of 1440 mF cm^(-2)at 4 mA cm^(-2).A novel shape-adaptable polymer gel electrolyte-assisted flexible quasi-solid-state hybrid SC(FQHSC)device constructed with P@NMgS-2 as a positive electrode and activated carbon as a negative electrode demonstrates the maximum power and energy density values of 14.13 mW cm^(-2)and 0.18 mWh cm^(-2),respectively,followed by outstanding cycling stability(∼100%capacitance retention over 50,000 cycles).Furthermore,the FQHSC device successfully powered electronic devices with no serious degradation upon bending and twisting for wearable electronic applications.
基金financially supported by National Natural Science Foundation of China(Nos.11935005 and 11875101)the Fundamental Research Funds for the Central Universities(No.DUT21LAB110)。
文摘In this work,a two-dimensional hybrid model,which consists of a bulk fluid module,a sheath module and an ion Monte-Carlo module,is developed to investigate the modulation of ion energy and angular distributions at different radial positions in a biased argon inductively coupled plasma.The results indicate that when the bias voltage amplitude increases or the bias frequency decreases,the ion energy peak separation width becomes wider.Besides,the widths of the ion energy peaks at the edge of the substrate are smaller than those at the center due to the lower plasma density there,indicating the nonuniformity of the ion energy distribution function(IEDF)along the radial direction.As the pressure increases from 1 to 10 Pa,the discrepancy of the IEDFs at different radial positions becomes more obvious,i.e.the IEDF at the radial edge is characterized by multiple low energy peaks.When a dual frequency bias source is applied,the IEDF exhibits three or four peaks,and it could be modulated efficiently by the relative phase between the two bias frequencies.The results obtained in this work could help to improve the radial uniformity of the IEDF and thus the etching process.
文摘A hybrid heat pump(compression/absorption)with an integrated thermal photovoltaic unit is studied.The considered working fluids are organic mixtures:R245fa/DMAC and R236fa/DMAC,chosen for their low Global Warming Potential.The main objective is the optimization of energy efficiency in order to minimize the environmental impact through the implementation of a sustainable strategy.It is shown that Exergy Analysis itself is a valuable tool in energy integration.Within the imposed framework of minimizing total annual costs,entropy analysis can be instrumental in determining the optimal plant concept,optimizing energy conversion and use,and improving profitability.The present results are discussed under the optimistic hope that they may help to define new energy and environmental policies.
基金funding this work through the Research Group Program under the Grant Number:(R.G.P.2/382/44).
文摘Many plant species have a startling degree of morphological similarity,making it difficult to split and categorize them reliably.Unknown plant species can be challenging to classify and segment using deep learning.While using deep learning architectures has helped improve classification accuracy,the resulting models often need to be more flexible and require a large dataset to train.For the sake of taxonomy,this research proposes a hybrid method for categorizing guava,potato,and java plumleaves.Two new approaches are used to formthe hybridmodel suggested here.The guava,potato,and java plum plant species have been successfully segmented using the first model built on the MobileNetV2-UNET architecture.As a second model,we use a Plant Species Detection Stacking Ensemble Deep Learning Model(PSD-SE-DLM)to identify potatoes,java plums,and guava.The proposed models were trained using data collected in Punjab,Pakistan,consisting of images of healthy and sick leaves from guava,java plum,and potatoes.These datasets are known as PLSD and PLSSD.Accuracy levels of 99.84%and 96.38%were achieved for the suggested PSD-SE-DLM and MobileNetV2-UNET models,respectively.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.62205231 and 22002102)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(Grant No.KYCX223271)Jiangsu Key Laboratory for Environment Functional Materials。
文摘Multilevel phase-change memory is an attractive technology to increase storage capacity and density owing to its high-speed,scalable and non-volatile characteristics.However,the contradiction between thermal stability and operation speed is one of key factors to restrain the development of phase-change memory.Here,N-doped Ge_(2)Sb_(2)Te_(5)-based optoelectronic hybrid memory is proposed to simultaneously implement high thermal stability and ultrafast operation speed.The picosecond laser is adopted to write/erase information based on reversible phase transition characteristics whereas the resistance is detected to perform information readout.Results show that when N content is 27.4 at.%,N-doped Ge_(2)Sb_(2)Te_(5)film possesses high ten-year data retention temperature of 175℃and low resistance drift coefficient of 0.00024 at 85℃,0.00170 at 120℃,and 0.00249 at 150℃,respectively,owing to the formation of Ge–N,Sb–N,and Te–N bonds.The SET/RESET operation speeds of the film reach 520 ps/13 ps.In parallel,the reversible switching cycle of the corresponding device is realized with the resistance ratio of three orders of magnitude.Four-level reversible resistance states induced by various crystallization degrees are also obtained together with low resistance drift coefficients.Therefore,the N-doped Ge_(2)Sb_(2)Te_(5)thin film is a promising phase-change material for ultrafast multilevel optoelectronic hybrid storage.