Ultra-low emission of nitrogen oxide(NO_(x))is an irreversible trend for the development of waste-to-energy industry.But traditional approaches to remove NO_(x) face significant challenge s,such as low denitration eff...Ultra-low emission of nitrogen oxide(NO_(x))is an irreversible trend for the development of waste-to-energy industry.But traditional approaches to remove NO_(x) face significant challenge s,such as low denitration efficiency,complex denitration system,and high investment and operating cost.Here we put forward a novel polymer non-catalytic reduction(PNCR)technology that utilized a new type of polymer agent to remove NO_(x),and the proposed PNCR technology was applied to the existing waste-to-energy plant to test the denitration performance.The PNCR technology demonstrated excellent denitration performance with a NO_(x) emission concentration of<100 mg/Nm^(3) and high denitration efficiency of>75%at the temperature range of 800-900℃,which showed the application feasibility even on the complex and unstable industrial operating conditions.In addition,PNCR and hybrid polymer/selective non-catalytic reduction(PNCR/SNCR)technology possessed remarkable economic advantages including low investment fee and low operating cost of<10 CNY per ton of municipal solid waste(MSW)compared with selective catalytic reduction(SCR)technology.The excellent denitration performance of PNCR technology forebodes a broad industrial application prospect in the field of flue gas cleaning for waste-to-energy plants.展开更多
In this paper,a wideband true time delay line for X-band is designed to overcome the beam dispersion problem in a high-resolution spaceborne synthetic aperture radar phased array antenna system.The delay line loads th...In this paper,a wideband true time delay line for X-band is designed to overcome the beam dispersion problem in a high-resolution spaceborne synthetic aperture radar phased array antenna system.The delay line loads the electromagnetic bandgap structure on the upper surface of the substrate integrated waveguide.This is equivalent to including an additional inductance-capacitance for energy storage,which realizes the slow-wave effect.A microstrip line-SIW tapered transition structure is introduced to achieve a low loss and a large bandwidth.In the frequency band between 8-12 GHz,the measured results show that the delay multiplier of the delay line reaches 4 times,i.e.,delay line’s delay time is 4 times larger than 50Ωmicrostrip line with same length.Furthermore,the delay fluctuation,i.e.,the difference between the maximum and minimum delay as a percentage of the standard delay is only 2.5%,the insertion loss is less than-2.5 dB,and the return loss is less than-15 dB.Compared with the existing delay lines,the proposed delay line has the advantages of high delay efficiency,low delay error,wide bandwidth and low loss,which has good practical value and application prospects.展开更多
BACKGROUND In 2017,our institution implemented a high efficiency(HE)pathway for lower limb orthopedic surgery.The employed strategy included patient selection,surgical instrument standardization,preoperative surgical ...BACKGROUND In 2017,our institution implemented a high efficiency(HE)pathway for lower limb orthopedic surgery.The employed strategy included patient selection,surgical instrument standardization,preoperative surgical nerve blocks,avoidance of general anesthesia and bypassing phase one recovery.We conducted a historic cohort study whose primary outcome was the postoperative recovery time between the HE and traditional(T)pathway.AIM To determine whether the implementation of a HE pathway was correlated with a reduction in postoperative recovery time.METHODS Patients who had unilateral elective lower limb orthopedic procedures through the T and HE pathway were screened between 2017 to 2019.Patients were at least 18 years old,and American Society of Anesthesiologists(ASA)Physical Status I to III without major systemic comorbidities were included.Propensity score was generated using multivariable regression taking age,body mass index,sex,ASA class and surgical type as covariates using nearest neighbour methods between the two pathways.Mann Whitney U test were used to analyzed total postoperative time.RESULTS There was an associated reduction in total postoperative recovery time of 63 minutes(95%CI:-69 to-57)in the HE group.The operating room time and total length of stay also had an associated decrease of 20 minutes(95%CI:-23 to-17)and 84 minutes(95%CI:-92 to-75)respectively.CONCLUSION Utilizing multifaceted strategies to improve perioperative efficiency was associated with a reduction in the postoperative recovery time in our retrospective study.This model can be a potential strategy to deal with surgical backlog in the face of ongoing human resource challenges.展开更多
Chinese cabbage(Brassica rapa subsp.pekinensis)is a widely cultivated vegetable crop in Asia with significant economic importance(Li et al.,2024;Yu et al.,2024).As a potyvirus with the broad host range,turnip mosaic v...Chinese cabbage(Brassica rapa subsp.pekinensis)is a widely cultivated vegetable crop in Asia with significant economic importance(Li et al.,2024;Yu et al.,2024).As a potyvirus with the broad host range,turnip mosaic virus(TuMV)is a major pathogen affecting Chinese cabbages,leading to severe yield losses(Li et al.,2019).Traditional control measures have shown limited efficacy,and the long-term use of chemical pesticides has led to significant issues such as environmental pollution and pathogen resistance(Samara et al.,2021;Lu et al.,2022).Biologicallyderived pesticides have garnered considerable attention owing to their eco-friendly attributes(Ayilara et al.,2023).γ-Aminobutyric acid(GABA),initially discovered in potato tubers,has been proven to regulate immune responses and enhance resistance to fungal and bacterial pathogens by modulating reactive oxygen species and stress-related hormone signals(Tarkowski et al.,2020;Wang et al.,2025).But biologically-derived agents typically face challenges such as large particle size and instability,which limit their practical application and bioavailability(Daraban et al.,2023).展开更多
The delayed nitrogen application technology is a crucial method for achieving high yield and efficiency in wheat cultivation.Specifically,more nitrogen is supplied to the middle and late growth stages of wheat by adju...The delayed nitrogen application technology is a crucial method for achieving high yield and efficiency in wheat cultivation.Specifically,more nitrogen is supplied to the middle and late growth stages of wheat by adjusting the application time and proportion of nitrogen fertilizer.This approach helps improve the tiller-bearing percentage and increase the number of grains per ear and the thousand-grain weight,while also reducing nitrogen loss and enhancing fertilizer use efficiency.This paper systematically elaborated on the high-yield and high-efficiency cultivation technology system with delayed nitrogen application for wheat,covering variety selection,soil management,sowing technology,the principle and implementation methods of delayed nitrogen application,integrated water and fertilizer management,field management,and comprehensive pest and disease control.Considering the ecological characteristics of major wheat-growing regions in China,tailored technical solutions were proposed,and operational key points of critical technological steps were introduced in detail.Through scientific variety distribution,precise nitrogen management,and integrated pest control,wheat yield and quality can be enhanced while achieving cost saving,improved efficiency,and ecological environmental protection.This paper provides systematic theoretical guidance and practical references for promoting thedelayed nitrogen application technology in wheat,thereby supporting the sustainable development of China s wheat industry.展开更多
The manufacturing industry is the core support for the development of the real economy.While promoting rapid economic growth,it also brings severe resource and environmental challenges.China's manufacturing indust...The manufacturing industry is the core support for the development of the real economy.While promoting rapid economic growth,it also brings severe resource and environmental challenges.China's manufacturing industry has ranked first in the world in terms of energy consumption,accounting for 56%of China's total energy consumption.Its electricity consumption exceeds 50%of the total social electricity consumption,and its carbon emissions reach 1.81 billion tons,accounting for 34% of the national total.Against this backdrop,enhancing the sustainability of high-end equipment manufacturing industries represented by aerospace has become a major strategic need for China's modernization,and it also provides strong support for solving global environmental problems.展开更多
The agricultural sector, encompassing agriculture, forestry, and land use, significantly contributes to global greenhouse gas(GHG) emissions, accounting for 23% of the total(IPCC 2019). It faces substantial challenges...The agricultural sector, encompassing agriculture, forestry, and land use, significantly contributes to global greenhouse gas(GHG) emissions, accounting for 23% of the total(IPCC 2019). It faces substantial challenges due to population growth and the urgent need to reduce its GHG emissions. Livestock husbandry, a crucial component of agriculture, accounts for a significant proportion of agricultural GHG emissions(Nugrahaeningtyas et al. 2024). Reducing emissions from livestock is essential not only for addressing climate change but also for protecting the ecological environment and achieving sustainable development. This is a critical task for the future of our planet and the well-being of future generations.展开更多
A novel Eu^(3+)-doped fluorapatite red phosphor Ca_(2)Y_(8)(BO_(4))_(2)(SiO_(4))_(4)F_(2)Eu^(3+)with pure phase was synthesized in this study.Density functional theory(DFT)calculation and diffuse reflection spectrum a...A novel Eu^(3+)-doped fluorapatite red phosphor Ca_(2)Y_(8)(BO_(4))_(2)(SiO_(4))_(4)F_(2)Eu^(3+)with pure phase was synthesized in this study.Density functional theory(DFT)calculation and diffuse reflection spectrum analysis reveal its potential as a matrix for phosphors excited by ultraviolet light.Eu^(3+)has a^(7)F_(0)→^(5)L_(6)transition at 394 nm,and the prepared phosphor exhibits a high emission intensity at 614 nm,which may be attributed to the^(5)D_(0)-^(7)F_(2)energy transition at the lower symmetry site of Eu^(3+).The optimal doping concentration of the phosphor is determined to be 11 mol%,with concentration quenching attributed to the exchange interaction mechanism.The overall color purity of the phosphor is up to 99.88%,with an internal quantum efficiency as high as 91.15%.Notably,Ca_(2)Y_(8)(BO_(4))_(2)(SiO_(4))_(4)F_(2):11 mol%Eu^(3+)(CYBSF:11 mol%Eu^(3+))phosphors exhibit good thermal stability,with a thermal quenching temperature(T1/2)of 552 K and the intensity of emission at 423 K still at 88.89%of that at 298 K.The activation energy of the phosphor is up to 0.30287 eV.Its comprehensive luminescence performance surpasses that of commercial red phosphor,making it suitable for near ultraviolet excited warm white light emitting diode(NUV-WLED)with a high color rendering index(Ra=82)and a correlated color temperature(CCT)of 4339 K.Moreover,the phosphor achieves latent fingerprint visualization and anti-counterfeiting ink on different material surfaces:glass,aluminum foil,plastic and paper.Overall,the fluorapatite CYBSF:11 mol%Eu^(3+)phosphor holds great potential for multimodal applications due to its high quantum efficiency and good thermal stability.展开更多
Conventional superconducting nanowire single-photon detectors(SNSPDs)have been typically limited in their applications due to their size,weight,and power consumption,which confine their use to laboratory settings.Howe...Conventional superconducting nanowire single-photon detectors(SNSPDs)have been typically limited in their applications due to their size,weight,and power consumption,which confine their use to laboratory settings.However,with the rapid development of remote imaging,sensing technologies,and long-range quantum communication with fewer topographical constraints,the demand for high-efficiency single-photon detectors integrated with avionic platforms is rapidly growing.We herein designed and manufactured the first drone-based SNSPD system with a system detection efficiency(SDE)as high as 91.8%.This drone-based system incorporates high-performance NbTiN SNSPDs,a self-developed miniature liquid helium dewar,and custom-built integrated electrical setups,making it capable of being launched in complex topographical conditions.Such a drone-based SNSPD system may open the use of SNSPDs for applications that demand high SDE in complex environments.展开更多
An easily stackable multi-layer quasi-zero-stiffness(ML-QZS)meta-structure is proposed to achieve highly efficient vibration isolation performance at low frequency.First,the distributed shape optimization method is us...An easily stackable multi-layer quasi-zero-stiffness(ML-QZS)meta-structure is proposed to achieve highly efficient vibration isolation performance at low frequency.First,the distributed shape optimization method is used to design the unit cel,i.e.,the single-layer QZS(SL-QZS)meta-structure.Second,the stiffness feature of the unit cell is investigated and verified through static experiments.Third,the unit cells are stacked one by one along the direction of vibration isolation,and thus the ML-QZS meta-structure is constructed.Fourth,the dynamic modeling of the ML-QZS vibration isolation metastructure is conducted,and the dynamic responses are obtained from the equations of motion,and verified by finite element(FE)simulations.Finally,a prototype of the ML-QZS vibration isolation meta-structure is fabricated by additive manufacturing,and the vibration isolation performance is evaluated experimentally.The results show that the vibration isolation performance substantially enhances when the number of unit cells increases.More importantly,the ML-QZS meta-structure can be easily extended in the direction of vibration isolation when the unit cells are properly stacked.Hence,the ML-FQZS vibration isolation meta-structure should be a fascinating solution for highly efficient vibration isolation performance at low frequency.展开更多
Solar steam generation(SSG)is widely regarded as one of the most sustainable technologies for seawater desalination.However,salt fouling severely compromises the evaporation performance and lifetime of evaporators,lim...Solar steam generation(SSG)is widely regarded as one of the most sustainable technologies for seawater desalination.However,salt fouling severely compromises the evaporation performance and lifetime of evaporators,limiting their practical applications.Herein,we propose a hierarchical salt-rejection(HSR)strategy to prevent salt precipitation during long-term evaporation while maintaining a rapid evaporation rate,even in high-salinity brine.The salt diffusion process is segmented into three steps—insulation,branching diffusion,and arterial transport—that significantly enhance the salt-resistance properties of the evaporator.Moreover,the HSR strategy overcomes the tradeoff between salt resistance and evaporation rate.Consequently,a high evaporation rate of 2.84 kg m^(-2) h^(-1),stable evaporation for 7 days cyclic tests in 20 wt%NaCl solution,and continuous operation for 170 h in natural seawater under 1 sun illumination were achieved.Compared with control evaporators,the HSR evaporator exhibited a>54%enhancement in total water evaporation mass during 24 h continuous evaporation in 20 wt%salt water.Furthermore,a water collection device equipped with the HSR evaporator realized a high water purification rate(1.1 kg m^(-2) h^(-1)),highlighting its potential for agricultural applications.展开更多
Experimental methods,including mercury pressure,nuclear magnetic resonance(NMR)and core(wateroil)displacement,are used to examine the effects of high-multiple water injection(i.e.water injection with high injected por...Experimental methods,including mercury pressure,nuclear magnetic resonance(NMR)and core(wateroil)displacement,are used to examine the effects of high-multiple water injection(i.e.water injection with high injected pore volume)on rock properties,pore structure and oil displacement efficiency of an oilfield in the western South China Sea.The results show an increase in the permeability of rocks along with particle migration,an increase in the pore volume and the average pore throat radius,and enhanced heterogeneity after high-multiple water injection.Compared with normal water injection methods,a high-multiple water injection is more effective in improving the oil displacement efficiency.The degree of recovery increases faster in the early stage due to the expansion of the swept area,and the transition from oil-wet to water-wet.The degree of recovery increases less in the late stage due to various factors,including the enhancement of heterogeneity in the rocks.Considering both the economic aspect and the production limit of water flooding,it is recommended to adopt other technologies to further enhance oil recovery after 300 PV water injection.展开更多
Organic-inorganic hybrid perovskite solar cells(PSCs)have garnered significant attention due to their high power conversion efficiency(PCE),low cost,and solution-processability.However,a substantial gap remains in the...Organic-inorganic hybrid perovskite solar cells(PSCs)have garnered significant attention due to their high power conversion efficiency(PCE),low cost,and solution-processability.However,a substantial gap remains in the certified efficiency of single-junction PSCs,primarily due to defects in perovskite films that accelerate nonradiative recombination of carriers.In this study,we designed a multifunctional thiourea derivative,amidinethiourea(ATU),as an additive to modulate the crystallization process of perovskite films and inhibit the formation of organic cations and iodine vacancies.Our work leverages the strong hydrogen-bonding interactions between guanidinium molecules and organic amine components,as well as the robust coordination effects between the C=S bonds in thiourea and Pb^(2+)ions.We demonstrate that ATU treatment significantly enhances the crystallinity of perovskite films,reduces defects,and improves charge transport properties.The ATU-treated PSCs achieved a PCE of 25.32%,with enhanced operational stability and reduced leakage current.Additionally,the ATU-treated perovskite films exhibited superior humidity and light-soaking stability,retaining 85.2%of their initial efficiency after 1500 h of exposure to ambient conditions.展开更多
The stability of perovskite solar cells(PSCs)is adversely affected by nonradiative recombination resulting from buried interface defects.Herein,we synthesize a polyionic liquid,poly(p-vinylbenzyl trimethylam-monium he...The stability of perovskite solar cells(PSCs)is adversely affected by nonradiative recombination resulting from buried interface defects.Herein,we synthesize a polyionic liquid,poly(p-vinylbenzyl trimethylam-monium hexafluorophosphate)(PTA),and introduce it into the buried interface of PSCs.The quaternary ammonium cation(N(-CH_(3))^(3+))in PTA can fill the vacancies of organic cations within the perovskite structure and reduce shallow energy level defects.Additionally,the hexafluorophosphate(PF6−)in PTA forms a Lewis acid-base interaction with Pb^(2+)in the perovskite layer,effectively passivating deep en-ergy level defects.Furthermore,hydrogen bonding can be established between organic cations and the PF6−anion,preventing the formation of shallow energy level defects.Through this synergistic mecha-nism,the deep and shallow energy level defects are effectively mitigated,resulting in improved device performance.As a result,the resulting treated inverted PSC exhibits an impressive power conversion ef-ficiency(PCE)of 24.72%.Notably,the PTA-treated PSCs exhibit remarkable stability,with 88.5%of the original PCE retained after undergoing heat aging at 85℃ for 1078 h,and 89.1%of the initial PCE main-tained following continuous exposure to light for 1100 h at the maximum power point.Synergistically suppressing multiple defects at the buried interface through the use of polyionic liquids is a promising way to improve the commercial viability of PSCs.展开更多
Li-rich Mn-based oxides(LRMOs)hold great promise as next-generation cathode materials for high-energy Li-ion batteries because of their low cost and high capacity.Nevertheless,the practical application of LRMOs is imp...Li-rich Mn-based oxides(LRMOs)hold great promise as next-generation cathode materials for high-energy Li-ion batteries because of their low cost and high capacity.Nevertheless,the practical application of LRMOs is impeded by their low initial Coulombic efficiency and rapid voltage decay.Herein,a V-doped layered-spinel coherent layer is constructed on the surface of a Co-free LRMO through a simple treatment with NH_(4)VO_(3).The layered-spinel coherent layer with 3D ion channels enhanced Li+diffusion efficiency,mitigates surface-inter-face reactions and suppresses irreversible oxygen release.Notably,V-doping significantly reduces the Bader charge of oxygen atoms,thereby impeding excessive oxidation of oxygen ions and further enhancing the stability of O-redox.The modified LRMO exhibites a remarkable initial Coulombic efficiency of 91.6%,signifi-cantly surpassing that of the original LRMO(74.4%).Furthermore,the treated sample showes an impressive capacity retention rate of 91.9%after 200 cycles,accompanied by a voltage decay of merely 0.47 mV per cycle.The proposed treatment approach is straightforward and significantly improves the initial Coulombic efficiency,voltage stability,and capacity stability of LRMO cathode materials,thus holding considerable promise for the development of high-energy Li-ion batteries.展开更多
Relaxor ferroic dielectrics have garnered increasing attention in the past decade as promising materials for energy storage.Among them,relaxor antiferroelectrics(AFEs)and relaxor ferroelectrics(FEs)have shown great pr...Relaxor ferroic dielectrics have garnered increasing attention in the past decade as promising materials for energy storage.Among them,relaxor antiferroelectrics(AFEs)and relaxor ferroelectrics(FEs)have shown great promise in term of high energy storage density and efficiency,respectively.In this study,a unique phase transition from relaxor AFE to relaxor FE was achieved for the first time by introducing strong-ferroelectricity BaTiO_(3)into NaNbO_(3)-BiFeO_(3)system,leading to an evolution from AFE R hierarchical nanodomains to FE polar nanoregions.A novel medium state,consisting of relaxor AFE and relaxor FE,was identified in the crossover of 0.88NaNbO_(3)–0.07BiFeO_(3)–0.05BaTiO_(3)ceramic,exhibiting a distinctive core-shell grain structure due to the composition segregation.By harnessing the advantages of high energy storage density from relaxor AFE and large efficiency from relaxor FE,the ceramic showcased excellent overall energy storage properties.It achieved a substantial recoverable energy storage density W_(rec)~13.1 J/cm^(3)and an ultrahigh efficiencyη~88.9%.These remarkable values shattered the trade-off relationship typically observed in most dielectric capacitors between W_(rec)andη.The findings of this study provide valuable insights for the design of ceramic capacitors with enhanced performance,specifically targeting the development of next generation pulse power devices.展开更多
The yield and nitrogen use efficiency(NUE)of hybrid rice combinations are closely related to restorer line.Therefore,it is essential to evaluate the agronomic characteristics of restorer lines with high yield and high...The yield and nitrogen use efficiency(NUE)of hybrid rice combinations are closely related to restorer line.Therefore,it is essential to evaluate the agronomic characteristics of restorer lines with high yield and high NUE(HYHN).However,it is unclear which restorer lines are HYHN,and neither have the common agronomic traits of the HYHN restorer lines been identified.Aiming to address this issue,we conducted two filed experiments using three nitrogen applications,which screened five HYHN restorer lines from 15 indica restorer lines.Yield,NUE and nutrient transportation of restorer lines with different yields and NUE types were examined.Yield and total nitrogen absorption in aboveground biomass(TNA)increased,whereas NUE for grain production decreased with increasing nitrogen application levels.The HYHN restorer lines had large spikelets and high weight per panicle that were significantly positively correlated with yield and NUE.Therefore,large sink potential may be beneficial for both yield and NUE.We further studied the differences in nutrient transportation to panicles between the HYHN and low yield and low NUE(LYLN)restorer lines and found that the former had a higher nitrogen absorption level and dry matter weight ratios of panicle in maturity.Moreover,the HYHN lines also had a higher root and neck-panicle node bleeding intensity per stem after heading and more developed vascular bundles of neck-panicle nodes and leaves than the LYLN lines,which could contribute to the transportation of nutrients from root to ground and from stem and leaf to spike.Therefore,the advantages of large sink potential of the HYHN restorer lines include large nutrient accumulation in and distribution to the panicles and smooth flow of nutrients along the transportation channels.展开更多
Studies for many years have indicated that the seed yield of (Glycine max L. Merr.) soybean can be increased by increasing photosynthetic efficiency. The yield of cultivars with high photosynthetic efficiency (HPE) in...Studies for many years have indicated that the seed yield of (Glycine max L. Merr.) soybean can be increased by increasing photosynthetic efficiency. The yield of cultivars with high photosynthetic efficiency (HPE) increased by 30% - 40% in comparison with the cultivars with normal photosynthetic efficiency, indicating that the breeding of soybean by increasing RPE may have a bright prospect. HPE breeding can be used as the temporal monitoring in the breeding process to avoid the divergency of the predetermined goal, although HPE breeding does not shorten the breeding time. It was observed that limited C-4 pathway exists in soybean leaf and pod, suggesting that by increasing the genetic expression of some C-4 enzymes in C-3 crops through traditional or genetic engineering techniques, new breakthroughs in increasing the photosynthetic efficiency of C-3 plant may be practicable in the future.展开更多
Two new AlTiN coated cemented carbide drills with Al content of 40% and 55% in weight are developed for high efficiency dry drilling of 40Cr. By studying tool durability, machined hole quality, tool wear mechanism, ch...Two new AlTiN coated cemented carbide drills with Al content of 40% and 55% in weight are developed for high efficiency dry drilling of 40Cr. By studying tool durability, machined hole quality, tool wear mechanism, chip deformation, and lubrication, the dry drilling performance of the two kinds of coated drills is analyzed. Experimental results show that the AlTiN coated drills are suitable for high efficiency dry drilling and can obtain higher quality of machined holes. The tool durability of the drill with 55% Al content is 1. 3 times of that of the drill with 40% Al content at the cutting speed of 90 m/min. The wear mechanism of two AlTiN coatings are studied in experiments. During dry drilling process, oxidative wear appears in both two kinds of drills. The oxide film is formed on the top of the coated drill containing Al content of 55%. And the oxide film helps to increase its high temperature resistance and decrease the coating flaking, thus the drill is failed because of coating subsidence. The drill with less Al content is failed due to peeling and breakage. The lubricated condition in dry drilling is improved by the high Al content coating. It helps to reduce the cutting deformation and benefits to improve the quality of machined holes. The AlTiN coating with higher Al content shows longer tool life and higher quality of machined holes in high efficiency dry drilling. Its tool life increases by 30% compared with that of the coating with less Al content.展开更多
[Objective] This study aimed to investigate differences in phosphorus effi-ciency between two-rowed barley and multiple-rowed barley and differences in phos-phorus efficiency among various agronomic traits, and to exp...[Objective] This study aimed to investigate differences in phosphorus effi-ciency between two-rowed barley and multiple-rowed barley and differences in phos-phorus efficiency among various agronomic traits, and to explore the relationship be-tween agronomic traits and row type with phosphorus efficiency. [Method] Under available phosphorus mass fractions of 1.32 and 36.6 mg/kg, 172 barley varieties, including 79 two-rowed foreign barley, 22 multiple-rowed foreign barley, 58 two-rowed Chinese barley and 13 multiple-rowed Chinese barley, were selected to com-pare differences in phosphorus efficiency-related agronomic traits. Plant height, spike length, number of unfil ed grains, number of unfil ed grains, main panicle weight, to-tal panicle weight, total stem weight, weight of aerial part and heading stage were surveyed for statistical analysis. [Result] The results showed that, various agronomic traits were larger under fertilization condition than under non-fertilization condition ex-cept number of unfil ed grains and heading stage. Plant high, spike length, weight of aerial part and heading stage varied greatly under non-fertilization condition; number of fil ed grains, number of unfil ed grains and total stem weight varied greatly under fertilization condition. In two-rowed barley, plant height and number of fil ed grains of Chinese varieties were higher than those of foreign varieties, while other agronomic traits such as spike length, number of unfil ed grains, main panicle weight, total panicle weight, total stem weight, weight of aerial part and heading stage of foreign varieties were higher than those of Chinese varieties. Spike length and weight of aerial part in multiple-rowed and two-rowed foreign barley were higher than those in Chinese barley. In multiple-rowed barley, plant height, number of unfil ed grains, total panicle weight and total stem weight of foreign varieties were higher under non-fer-tilization condition and lower under fertilization condition compared with those of Chi-nese varieties; number of fil ed grains, main panicle weight and heading stage of foreign varieties were lower under non-fertilization condition and higher under fertil-ization condition compared with those of Chinese varieties. [Conclusion] Heading stage, number of fil ed grains, number of unfil ed grains and total stem weight are more sensitive to phosphorus efficiency. Multiple-rowed barley is more sensitive to phosphorus efficiency than two-rowed barley.展开更多
基金supported by the National Natural Science Foundation of China(No.92367107)。
文摘Ultra-low emission of nitrogen oxide(NO_(x))is an irreversible trend for the development of waste-to-energy industry.But traditional approaches to remove NO_(x) face significant challenge s,such as low denitration efficiency,complex denitration system,and high investment and operating cost.Here we put forward a novel polymer non-catalytic reduction(PNCR)technology that utilized a new type of polymer agent to remove NO_(x),and the proposed PNCR technology was applied to the existing waste-to-energy plant to test the denitration performance.The PNCR technology demonstrated excellent denitration performance with a NO_(x) emission concentration of<100 mg/Nm^(3) and high denitration efficiency of>75%at the temperature range of 800-900℃,which showed the application feasibility even on the complex and unstable industrial operating conditions.In addition,PNCR and hybrid polymer/selective non-catalytic reduction(PNCR/SNCR)technology possessed remarkable economic advantages including low investment fee and low operating cost of<10 CNY per ton of municipal solid waste(MSW)compared with selective catalytic reduction(SCR)technology.The excellent denitration performance of PNCR technology forebodes a broad industrial application prospect in the field of flue gas cleaning for waste-to-energy plants.
基金Supported by the National Natural Science Foundation of China(61971401)。
文摘In this paper,a wideband true time delay line for X-band is designed to overcome the beam dispersion problem in a high-resolution spaceborne synthetic aperture radar phased array antenna system.The delay line loads the electromagnetic bandgap structure on the upper surface of the substrate integrated waveguide.This is equivalent to including an additional inductance-capacitance for energy storage,which realizes the slow-wave effect.A microstrip line-SIW tapered transition structure is introduced to achieve a low loss and a large bandwidth.In the frequency band between 8-12 GHz,the measured results show that the delay multiplier of the delay line reaches 4 times,i.e.,delay line’s delay time is 4 times larger than 50Ωmicrostrip line with same length.Furthermore,the delay fluctuation,i.e.,the difference between the maximum and minimum delay as a percentage of the standard delay is only 2.5%,the insertion loss is less than-2.5 dB,and the return loss is less than-15 dB.Compared with the existing delay lines,the proposed delay line has the advantages of high delay efficiency,low delay error,wide bandwidth and low loss,which has good practical value and application prospects.
文摘BACKGROUND In 2017,our institution implemented a high efficiency(HE)pathway for lower limb orthopedic surgery.The employed strategy included patient selection,surgical instrument standardization,preoperative surgical nerve blocks,avoidance of general anesthesia and bypassing phase one recovery.We conducted a historic cohort study whose primary outcome was the postoperative recovery time between the HE and traditional(T)pathway.AIM To determine whether the implementation of a HE pathway was correlated with a reduction in postoperative recovery time.METHODS Patients who had unilateral elective lower limb orthopedic procedures through the T and HE pathway were screened between 2017 to 2019.Patients were at least 18 years old,and American Society of Anesthesiologists(ASA)Physical Status I to III without major systemic comorbidities were included.Propensity score was generated using multivariable regression taking age,body mass index,sex,ASA class and surgical type as covariates using nearest neighbour methods between the two pathways.Mann Whitney U test were used to analyzed total postoperative time.RESULTS There was an associated reduction in total postoperative recovery time of 63 minutes(95%CI:-69 to-57)in the HE group.The operating room time and total length of stay also had an associated decrease of 20 minutes(95%CI:-23 to-17)and 84 minutes(95%CI:-92 to-75)respectively.CONCLUSION Utilizing multifaceted strategies to improve perioperative efficiency was associated with a reduction in the postoperative recovery time in our retrospective study.This model can be a potential strategy to deal with surgical backlog in the face of ongoing human resource challenges.
基金supported by the National Natural Science Foundation of China(Grant Nos.32402564,32330096,32372631)Hebei Natural Science Foundation(Grant No.C2024204246)+1 种基金the Pinduoduo-China Agricultural University Research Fund(Grant No.PC2023B02018)the 2115 Talent Development Program of China Agricultural University.
文摘Chinese cabbage(Brassica rapa subsp.pekinensis)is a widely cultivated vegetable crop in Asia with significant economic importance(Li et al.,2024;Yu et al.,2024).As a potyvirus with the broad host range,turnip mosaic virus(TuMV)is a major pathogen affecting Chinese cabbages,leading to severe yield losses(Li et al.,2019).Traditional control measures have shown limited efficacy,and the long-term use of chemical pesticides has led to significant issues such as environmental pollution and pathogen resistance(Samara et al.,2021;Lu et al.,2022).Biologicallyderived pesticides have garnered considerable attention owing to their eco-friendly attributes(Ayilara et al.,2023).γ-Aminobutyric acid(GABA),initially discovered in potato tubers,has been proven to regulate immune responses and enhance resistance to fungal and bacterial pathogens by modulating reactive oxygen species and stress-related hormone signals(Tarkowski et al.,2020;Wang et al.,2025).But biologically-derived agents typically face challenges such as large particle size and instability,which limit their practical application and bioavailability(Daraban et al.,2023).
基金Supported by The Key Science and Technology Project of Shangqiu City(2024056).
文摘The delayed nitrogen application technology is a crucial method for achieving high yield and efficiency in wheat cultivation.Specifically,more nitrogen is supplied to the middle and late growth stages of wheat by adjusting the application time and proportion of nitrogen fertilizer.This approach helps improve the tiller-bearing percentage and increase the number of grains per ear and the thousand-grain weight,while also reducing nitrogen loss and enhancing fertilizer use efficiency.This paper systematically elaborated on the high-yield and high-efficiency cultivation technology system with delayed nitrogen application for wheat,covering variety selection,soil management,sowing technology,the principle and implementation methods of delayed nitrogen application,integrated water and fertilizer management,field management,and comprehensive pest and disease control.Considering the ecological characteristics of major wheat-growing regions in China,tailored technical solutions were proposed,and operational key points of critical technological steps were introduced in detail.Through scientific variety distribution,precise nitrogen management,and integrated pest control,wheat yield and quality can be enhanced while achieving cost saving,improved efficiency,and ecological environmental protection.This paper provides systematic theoretical guidance and practical references for promoting thedelayed nitrogen application technology in wheat,thereby supporting the sustainable development of China s wheat industry.
基金the support of the National Natural Science Foundation of China(Nos.52205476 and 52175415)the Natural Science Foundation of Jiangsu Province(No.BK20242040)+1 种基金the Fundamental Research Funds for the Central Universities(No.NG2024008)the Fund of Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology(No.1005ZAA20003-14)。
文摘The manufacturing industry is the core support for the development of the real economy.While promoting rapid economic growth,it also brings severe resource and environmental challenges.China's manufacturing industry has ranked first in the world in terms of energy consumption,accounting for 56%of China's total energy consumption.Its electricity consumption exceeds 50%of the total social electricity consumption,and its carbon emissions reach 1.81 billion tons,accounting for 34% of the national total.Against this backdrop,enhancing the sustainability of high-end equipment manufacturing industries represented by aerospace has become a major strategic need for China's modernization,and it also provides strong support for solving global environmental problems.
文摘The agricultural sector, encompassing agriculture, forestry, and land use, significantly contributes to global greenhouse gas(GHG) emissions, accounting for 23% of the total(IPCC 2019). It faces substantial challenges due to population growth and the urgent need to reduce its GHG emissions. Livestock husbandry, a crucial component of agriculture, accounts for a significant proportion of agricultural GHG emissions(Nugrahaeningtyas et al. 2024). Reducing emissions from livestock is essential not only for addressing climate change but also for protecting the ecological environment and achieving sustainable development. This is a critical task for the future of our planet and the well-being of future generations.
基金supported by the National Natural Science Foundation of China(52372013)Natural Science Foundation of Shanghai(22ZR1460600)。
文摘A novel Eu^(3+)-doped fluorapatite red phosphor Ca_(2)Y_(8)(BO_(4))_(2)(SiO_(4))_(4)F_(2)Eu^(3+)with pure phase was synthesized in this study.Density functional theory(DFT)calculation and diffuse reflection spectrum analysis reveal its potential as a matrix for phosphors excited by ultraviolet light.Eu^(3+)has a^(7)F_(0)→^(5)L_(6)transition at 394 nm,and the prepared phosphor exhibits a high emission intensity at 614 nm,which may be attributed to the^(5)D_(0)-^(7)F_(2)energy transition at the lower symmetry site of Eu^(3+).The optimal doping concentration of the phosphor is determined to be 11 mol%,with concentration quenching attributed to the exchange interaction mechanism.The overall color purity of the phosphor is up to 99.88%,with an internal quantum efficiency as high as 91.15%.Notably,Ca_(2)Y_(8)(BO_(4))_(2)(SiO_(4))_(4)F_(2):11 mol%Eu^(3+)(CYBSF:11 mol%Eu^(3+))phosphors exhibit good thermal stability,with a thermal quenching temperature(T1/2)of 552 K and the intensity of emission at 423 K still at 88.89%of that at 298 K.The activation energy of the phosphor is up to 0.30287 eV.Its comprehensive luminescence performance surpasses that of commercial red phosphor,making it suitable for near ultraviolet excited warm white light emitting diode(NUV-WLED)with a high color rendering index(Ra=82)and a correlated color temperature(CCT)of 4339 K.Moreover,the phosphor achieves latent fingerprint visualization and anti-counterfeiting ink on different material surfaces:glass,aluminum foil,plastic and paper.Overall,the fluorapatite CYBSF:11 mol%Eu^(3+)phosphor holds great potential for multimodal applications due to its high quantum efficiency and good thermal stability.
基金the Innovation Program for Quantum Science and Technology(Grant No.2023ZD0300100)the National Key Research and Development Program of China(Grant Nos.2023YFB3809600 and 2023YFC3007801)+1 种基金the National Natural Science Foundation of China(Grant Nos.62301543 and U24A20320)the Shanghai Sailing Program(Grant No.21YF1455700).
文摘Conventional superconducting nanowire single-photon detectors(SNSPDs)have been typically limited in their applications due to their size,weight,and power consumption,which confine their use to laboratory settings.However,with the rapid development of remote imaging,sensing technologies,and long-range quantum communication with fewer topographical constraints,the demand for high-efficiency single-photon detectors integrated with avionic platforms is rapidly growing.We herein designed and manufactured the first drone-based SNSPD system with a system detection efficiency(SDE)as high as 91.8%.This drone-based system incorporates high-performance NbTiN SNSPDs,a self-developed miniature liquid helium dewar,and custom-built integrated electrical setups,making it capable of being launched in complex topographical conditions.Such a drone-based SNSPD system may open the use of SNSPDs for applications that demand high SDE in complex environments.
基金supported by the National Natural Science Foundation of China(Nos.12122206 and 12272129)the Natural Science Foundation of Hunan Province of China(No.2024JJ4004)the Zhejiang Provincial Natural Science Foundation of China(No.LQ24A020006)。
文摘An easily stackable multi-layer quasi-zero-stiffness(ML-QZS)meta-structure is proposed to achieve highly efficient vibration isolation performance at low frequency.First,the distributed shape optimization method is used to design the unit cel,i.e.,the single-layer QZS(SL-QZS)meta-structure.Second,the stiffness feature of the unit cell is investigated and verified through static experiments.Third,the unit cells are stacked one by one along the direction of vibration isolation,and thus the ML-QZS meta-structure is constructed.Fourth,the dynamic modeling of the ML-QZS vibration isolation metastructure is conducted,and the dynamic responses are obtained from the equations of motion,and verified by finite element(FE)simulations.Finally,a prototype of the ML-QZS vibration isolation meta-structure is fabricated by additive manufacturing,and the vibration isolation performance is evaluated experimentally.The results show that the vibration isolation performance substantially enhances when the number of unit cells increases.More importantly,the ML-QZS meta-structure can be easily extended in the direction of vibration isolation when the unit cells are properly stacked.Hence,the ML-FQZS vibration isolation meta-structure should be a fascinating solution for highly efficient vibration isolation performance at low frequency.
基金support provided by the Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone Shenzhen Park Project(HZQB-KCZYB-2020030)the Research Grants Council of Hong Kong(Project No:AoE/M-402/20.)+1 种基金the Open Project of Yunnan Precious Metals Laboratory Co.,Ltd(YPML-2023050248)the Hong Kong Innovation and Technology Commission via the Hong Kong Branch of National Precious Metals Material Engineering Research Center.
文摘Solar steam generation(SSG)is widely regarded as one of the most sustainable technologies for seawater desalination.However,salt fouling severely compromises the evaporation performance and lifetime of evaporators,limiting their practical applications.Herein,we propose a hierarchical salt-rejection(HSR)strategy to prevent salt precipitation during long-term evaporation while maintaining a rapid evaporation rate,even in high-salinity brine.The salt diffusion process is segmented into three steps—insulation,branching diffusion,and arterial transport—that significantly enhance the salt-resistance properties of the evaporator.Moreover,the HSR strategy overcomes the tradeoff between salt resistance and evaporation rate.Consequently,a high evaporation rate of 2.84 kg m^(-2) h^(-1),stable evaporation for 7 days cyclic tests in 20 wt%NaCl solution,and continuous operation for 170 h in natural seawater under 1 sun illumination were achieved.Compared with control evaporators,the HSR evaporator exhibited a>54%enhancement in total water evaporation mass during 24 h continuous evaporation in 20 wt%salt water.Furthermore,a water collection device equipped with the HSR evaporator realized a high water purification rate(1.1 kg m^(-2) h^(-1)),highlighting its potential for agricultural applications.
文摘Experimental methods,including mercury pressure,nuclear magnetic resonance(NMR)and core(wateroil)displacement,are used to examine the effects of high-multiple water injection(i.e.water injection with high injected pore volume)on rock properties,pore structure and oil displacement efficiency of an oilfield in the western South China Sea.The results show an increase in the permeability of rocks along with particle migration,an increase in the pore volume and the average pore throat radius,and enhanced heterogeneity after high-multiple water injection.Compared with normal water injection methods,a high-multiple water injection is more effective in improving the oil displacement efficiency.The degree of recovery increases faster in the early stage due to the expansion of the swept area,and the transition from oil-wet to water-wet.The degree of recovery increases less in the late stage due to various factors,including the enhancement of heterogeneity in the rocks.Considering both the economic aspect and the production limit of water flooding,it is recommended to adopt other technologies to further enhance oil recovery after 300 PV water injection.
基金financial support from various entities,including the National Natural Science Foundation of China[grant number 62405005]the Natural Science Research Project of Anhui Educational Committee[2024AH050314]+1 种基金the Foundation of Anhui Science and Technology University[grant number HCYJ202201]the Anhui Science and Technology University's Student Innovation and Entrepreneurship Training Program[grant numbers S202410879115,S202410879098]。
文摘Organic-inorganic hybrid perovskite solar cells(PSCs)have garnered significant attention due to their high power conversion efficiency(PCE),low cost,and solution-processability.However,a substantial gap remains in the certified efficiency of single-junction PSCs,primarily due to defects in perovskite films that accelerate nonradiative recombination of carriers.In this study,we designed a multifunctional thiourea derivative,amidinethiourea(ATU),as an additive to modulate the crystallization process of perovskite films and inhibit the formation of organic cations and iodine vacancies.Our work leverages the strong hydrogen-bonding interactions between guanidinium molecules and organic amine components,as well as the robust coordination effects between the C=S bonds in thiourea and Pb^(2+)ions.We demonstrate that ATU treatment significantly enhances the crystallinity of perovskite films,reduces defects,and improves charge transport properties.The ATU-treated PSCs achieved a PCE of 25.32%,with enhanced operational stability and reduced leakage current.Additionally,the ATU-treated perovskite films exhibited superior humidity and light-soaking stability,retaining 85.2%of their initial efficiency after 1500 h of exposure to ambient conditions.
基金supported by the Science,Technology,and Innovation Commission of Shenzhen Municipality(No.GJHZ20220913143204008)the Shccig-Qinling Program(No.SMYJY202300294C)+3 种基金National Natural Science Foundation of China(Nos.22261142666,52372225,52172237,22305191)the Shaanxi Science Fund for Distinguished Young Scholars(No.2022JC-21)the Research Fund of the State Key Laboratory of Solidification Processing(NPU)China(No.2021-QZ-02).
文摘The stability of perovskite solar cells(PSCs)is adversely affected by nonradiative recombination resulting from buried interface defects.Herein,we synthesize a polyionic liquid,poly(p-vinylbenzyl trimethylam-monium hexafluorophosphate)(PTA),and introduce it into the buried interface of PSCs.The quaternary ammonium cation(N(-CH_(3))^(3+))in PTA can fill the vacancies of organic cations within the perovskite structure and reduce shallow energy level defects.Additionally,the hexafluorophosphate(PF6−)in PTA forms a Lewis acid-base interaction with Pb^(2+)in the perovskite layer,effectively passivating deep en-ergy level defects.Furthermore,hydrogen bonding can be established between organic cations and the PF6−anion,preventing the formation of shallow energy level defects.Through this synergistic mecha-nism,the deep and shallow energy level defects are effectively mitigated,resulting in improved device performance.As a result,the resulting treated inverted PSC exhibits an impressive power conversion ef-ficiency(PCE)of 24.72%.Notably,the PTA-treated PSCs exhibit remarkable stability,with 88.5%of the original PCE retained after undergoing heat aging at 85℃ for 1078 h,and 89.1%of the initial PCE main-tained following continuous exposure to light for 1100 h at the maximum power point.Synergistically suppressing multiple defects at the buried interface through the use of polyionic liquids is a promising way to improve the commercial viability of PSCs.
基金Natural Science Research(Department of Education)Project of Higher Education Institutions in Guangdong Province(Grant No.2018KQNCX063)Applied Basic Research Fund of Guangdong Province(Grant No.2024B1515020071)+1 种基金National Natural Science Foundation of China(Grant Nos.52371217 and 52150410411)Guangdong Provincial Science and Technology Plan Project(Grant No.2023A0505020009)。
文摘Li-rich Mn-based oxides(LRMOs)hold great promise as next-generation cathode materials for high-energy Li-ion batteries because of their low cost and high capacity.Nevertheless,the practical application of LRMOs is impeded by their low initial Coulombic efficiency and rapid voltage decay.Herein,a V-doped layered-spinel coherent layer is constructed on the surface of a Co-free LRMO through a simple treatment with NH_(4)VO_(3).The layered-spinel coherent layer with 3D ion channels enhanced Li+diffusion efficiency,mitigates surface-inter-face reactions and suppresses irreversible oxygen release.Notably,V-doping significantly reduces the Bader charge of oxygen atoms,thereby impeding excessive oxidation of oxygen ions and further enhancing the stability of O-redox.The modified LRMO exhibites a remarkable initial Coulombic efficiency of 91.6%,signifi-cantly surpassing that of the original LRMO(74.4%).Furthermore,the treated sample showes an impressive capacity retention rate of 91.9%after 200 cycles,accompanied by a voltage decay of merely 0.47 mV per cycle.The proposed treatment approach is straightforward and significantly improves the initial Coulombic efficiency,voltage stability,and capacity stability of LRMO cathode materials,thus holding considerable promise for the development of high-energy Li-ion batteries.
基金financially supported by the National Natural Science Foundation of China(Nos.52172181,22105017)Interdisciplinary Research Project for Young Teachers of USTB(No.FRFIDRY-21–002)。
文摘Relaxor ferroic dielectrics have garnered increasing attention in the past decade as promising materials for energy storage.Among them,relaxor antiferroelectrics(AFEs)and relaxor ferroelectrics(FEs)have shown great promise in term of high energy storage density and efficiency,respectively.In this study,a unique phase transition from relaxor AFE to relaxor FE was achieved for the first time by introducing strong-ferroelectricity BaTiO_(3)into NaNbO_(3)-BiFeO_(3)system,leading to an evolution from AFE R hierarchical nanodomains to FE polar nanoregions.A novel medium state,consisting of relaxor AFE and relaxor FE,was identified in the crossover of 0.88NaNbO_(3)–0.07BiFeO_(3)–0.05BaTiO_(3)ceramic,exhibiting a distinctive core-shell grain structure due to the composition segregation.By harnessing the advantages of high energy storage density from relaxor AFE and large efficiency from relaxor FE,the ceramic showcased excellent overall energy storage properties.It achieved a substantial recoverable energy storage density W_(rec)~13.1 J/cm^(3)and an ultrahigh efficiencyη~88.9%.These remarkable values shattered the trade-off relationship typically observed in most dielectric capacitors between W_(rec)andη.The findings of this study provide valuable insights for the design of ceramic capacitors with enhanced performance,specifically targeting the development of next generation pulse power devices.
基金the National Natural Science Foundation of China(31871564)the National Key R&D Program of China(2016YFD0300506 and 2017YFD0301700)the Sichuan Breeding Key Research Project,China(2016NYZ0051)。
文摘The yield and nitrogen use efficiency(NUE)of hybrid rice combinations are closely related to restorer line.Therefore,it is essential to evaluate the agronomic characteristics of restorer lines with high yield and high NUE(HYHN).However,it is unclear which restorer lines are HYHN,and neither have the common agronomic traits of the HYHN restorer lines been identified.Aiming to address this issue,we conducted two filed experiments using three nitrogen applications,which screened five HYHN restorer lines from 15 indica restorer lines.Yield,NUE and nutrient transportation of restorer lines with different yields and NUE types were examined.Yield and total nitrogen absorption in aboveground biomass(TNA)increased,whereas NUE for grain production decreased with increasing nitrogen application levels.The HYHN restorer lines had large spikelets and high weight per panicle that were significantly positively correlated with yield and NUE.Therefore,large sink potential may be beneficial for both yield and NUE.We further studied the differences in nutrient transportation to panicles between the HYHN and low yield and low NUE(LYLN)restorer lines and found that the former had a higher nitrogen absorption level and dry matter weight ratios of panicle in maturity.Moreover,the HYHN lines also had a higher root and neck-panicle node bleeding intensity per stem after heading and more developed vascular bundles of neck-panicle nodes and leaves than the LYLN lines,which could contribute to the transportation of nutrients from root to ground and from stem and leaf to spike.Therefore,the advantages of large sink potential of the HYHN restorer lines include large nutrient accumulation in and distribution to the panicles and smooth flow of nutrients along the transportation channels.
文摘Studies for many years have indicated that the seed yield of (Glycine max L. Merr.) soybean can be increased by increasing photosynthetic efficiency. The yield of cultivars with high photosynthetic efficiency (HPE) increased by 30% - 40% in comparison with the cultivars with normal photosynthetic efficiency, indicating that the breeding of soybean by increasing RPE may have a bright prospect. HPE breeding can be used as the temporal monitoring in the breeding process to avoid the divergency of the predetermined goal, although HPE breeding does not shorten the breeding time. It was observed that limited C-4 pathway exists in soybean leaf and pod, suggesting that by increasing the genetic expression of some C-4 enzymes in C-3 crops through traditional or genetic engineering techniques, new breakthroughs in increasing the photosynthetic efficiency of C-3 plant may be practicable in the future.
文摘Two new AlTiN coated cemented carbide drills with Al content of 40% and 55% in weight are developed for high efficiency dry drilling of 40Cr. By studying tool durability, machined hole quality, tool wear mechanism, chip deformation, and lubrication, the dry drilling performance of the two kinds of coated drills is analyzed. Experimental results show that the AlTiN coated drills are suitable for high efficiency dry drilling and can obtain higher quality of machined holes. The tool durability of the drill with 55% Al content is 1. 3 times of that of the drill with 40% Al content at the cutting speed of 90 m/min. The wear mechanism of two AlTiN coatings are studied in experiments. During dry drilling process, oxidative wear appears in both two kinds of drills. The oxide film is formed on the top of the coated drill containing Al content of 55%. And the oxide film helps to increase its high temperature resistance and decrease the coating flaking, thus the drill is failed because of coating subsidence. The drill with less Al content is failed due to peeling and breakage. The lubricated condition in dry drilling is improved by the high Al content coating. It helps to reduce the cutting deformation and benefits to improve the quality of machined holes. The AlTiN coating with higher Al content shows longer tool life and higher quality of machined holes in high efficiency dry drilling. Its tool life increases by 30% compared with that of the coating with less Al content.
基金Supported by China Agriculture Research System(CARS-05)National Natural Science Foundation of China(No.31260326)Personnel Training Plan of Technological Innovation of Yunnan Province(No.2012HB050)~~
文摘[Objective] This study aimed to investigate differences in phosphorus effi-ciency between two-rowed barley and multiple-rowed barley and differences in phos-phorus efficiency among various agronomic traits, and to explore the relationship be-tween agronomic traits and row type with phosphorus efficiency. [Method] Under available phosphorus mass fractions of 1.32 and 36.6 mg/kg, 172 barley varieties, including 79 two-rowed foreign barley, 22 multiple-rowed foreign barley, 58 two-rowed Chinese barley and 13 multiple-rowed Chinese barley, were selected to com-pare differences in phosphorus efficiency-related agronomic traits. Plant height, spike length, number of unfil ed grains, number of unfil ed grains, main panicle weight, to-tal panicle weight, total stem weight, weight of aerial part and heading stage were surveyed for statistical analysis. [Result] The results showed that, various agronomic traits were larger under fertilization condition than under non-fertilization condition ex-cept number of unfil ed grains and heading stage. Plant high, spike length, weight of aerial part and heading stage varied greatly under non-fertilization condition; number of fil ed grains, number of unfil ed grains and total stem weight varied greatly under fertilization condition. In two-rowed barley, plant height and number of fil ed grains of Chinese varieties were higher than those of foreign varieties, while other agronomic traits such as spike length, number of unfil ed grains, main panicle weight, total panicle weight, total stem weight, weight of aerial part and heading stage of foreign varieties were higher than those of Chinese varieties. Spike length and weight of aerial part in multiple-rowed and two-rowed foreign barley were higher than those in Chinese barley. In multiple-rowed barley, plant height, number of unfil ed grains, total panicle weight and total stem weight of foreign varieties were higher under non-fer-tilization condition and lower under fertilization condition compared with those of Chi-nese varieties; number of fil ed grains, main panicle weight and heading stage of foreign varieties were lower under non-fertilization condition and higher under fertil-ization condition compared with those of Chinese varieties. [Conclusion] Heading stage, number of fil ed grains, number of unfil ed grains and total stem weight are more sensitive to phosphorus efficiency. Multiple-rowed barley is more sensitive to phosphorus efficiency than two-rowed barley.
