The current study of minimum quantity lubrication(MQL)concentrates on its performance improvement.By contrast with nanofluid MQL and electrostatic atomization(EA),the proposed nanofluid composite electrostatic sprayin...The current study of minimum quantity lubrication(MQL)concentrates on its performance improvement.By contrast with nanofluid MQL and electrostatic atomization(EA),the proposed nanofluid composite electrostatic spraying(NCES)can enhance the performance of MQL more comprehensively.However,it is largely influenced by the base fluid of external fluid.In this paper,the lubrication property and machining performance of NCES with different types of vegetable oils(castor,palm,soybean,rapeseed,and LB2000 oil)as the base fluids of external fluid were compared and evaluated by friction and milling tests under different flow ratios of external and internal fluids.The spraying current and electrowetting angle were tested to analyze the influence of vegetable oil type as the base fluid of external fluid on NCES performances.The friction test results show that relative to NCES with other vegetable oils as the base fluids of external fluid,NCES with LB2000 as the base fluid of external fluid reduced the friction coefficient and wear loss by 9.4%-27.7%and 7.6%-26.5%,respectively.The milling test results display that the milling force and milling temperature for NCES with LB2000 as the base fluid of external fluid were 1.4%-13.2%and 3.6%-11.2%lower than those for NCES with other vegetable oils as the base fluids of external fluid,respectively.When LB2000/multi-walled carbon nanotube(MWCNT)water-based nanofluid was used as the external/internal fluid and the flow ratio of external and internal fluids was 2:1,NCES showed the best milling performance.This study provides theoretical and technical support for the selection of the base fluid of NCES external fluid.展开更多
The technology for spraying a sintering bed and thus improving sinter quality indicators while reducing the emission of flue gas pollutants has recently become an important research topic.The impacts on sinter quality...The technology for spraying a sintering bed and thus improving sinter quality indicators while reducing the emission of flue gas pollutants has recently become an important research topic.The impacts on sinter quality and emissions when spraying the sintering surface with different amounts and flow rates of steam were investigated in this study.The sinter quality indicators were most effectively improved by spraying 180 g of steam flow continuously at a rate of 0.02 m^(3)/min for 15 min after ignition for 8 min.The optimal effect on emission reduction was obtained by spraying 90 g of steam flow continuously at a rate of 0.01 m^(3)/min for 15 min after ignition for 8 min.展开更多
The Fe-based amorphous metallic matrix coating (Fe-AMMC) was fabricated with the powder mixtures of Fe-based metallic glass synthesized with industrial raw materials, NiCr alloy and WC particle by high velocity oxy-...The Fe-based amorphous metallic matrix coating (Fe-AMMC) was fabricated with the powder mixtures of Fe-based metallic glass synthesized with industrial raw materials, NiCr alloy and WC particle by high velocity oxy-fuel (HVOF) spraying. The corrosion resistance of Fe-AMMC was investigated by potentiodynamic polarization tests in 1 mol/L HCl, NaCl, H2SO4 and NaOH solutions, respectively. The surface morphologies corroded were observed by SEM. The results indicate that Fe-AMMC exhibits excellent corrosion resistance, higher corrosion resistance than 304L stainless steel in the chloride solutions. The low corrosion current density and passive current density of Fe-AMMC with a wide spontaneous passivation region are about 132.0μA/cm2 and 9.0 mA/cm2 in HCl solution, and about 2.5 μA/cm2 and 2.3 mA/cm2 in NaCl solution. The excellent corrosion resistance demonstrates that Fe-based amorphous metallic matrix powder is a viable engineering material in practical anti-corrosion and anti-wear coating applications.展开更多
In order to explore the effect of spraying fertilizers after flowering on grain weight and nutritional quality of different winter wheat cultivars, twenty wheat culti- vars in wheat zones along Yellow River and Huai R...In order to explore the effect of spraying fertilizers after flowering on grain weight and nutritional quality of different winter wheat cultivars, twenty wheat culti- vars in wheat zones along Yellow River and Huai River, were used to investigate the change of thousand kernel weight (TKW), phytic acid content (PAC), contents of Fe, Zn and Mg and bioavailability by spraying zinc and nitrogen fertilizers after flowering. The results showed that both of TKW and protein content in grains in- creased by spraying Zn and N fertilizers, and the effect of N fertilizer proved more significant. The PAC decreased significantly after Zn treatment, for example, PAC of "955159", a wheat cultivar, decreased by 27.95%. However, PAC was in- significantly influenced by N fertilizer. On the other hand, Zn content in wheat grains were improved after spraying Zn fertilizer and the increase aveaged 54.38%. Furthermore, Fe and Zn contents grew significantly after spraying N fertilizer, and the increase averaged 36.88% and 11.25% respectively. However, Mg content in grains declined by N fertilizer. Still, the bioavailability of zinc in grains was enhanced after spraying Zn fertilizer, and of Fe was also increased greatly after spraying N fertilizer. In conclusion, grain weight, and content and effectiveness of mineral ele-ments can be improved simultaneously by rational spraying of N and Zn fertilizers to improve quality of grains.展开更多
[Objective] Changxuan 3S was thermo-sensitive genicmale sterile(TGMS)rice selected from irradiated seeds of Peiai 64S by 350 Gy^(60)Coγ-ray.The aim of the study was to confirm GA3 spraying dosage of Changxuan 3S ...[Objective] Changxuan 3S was thermo-sensitive genicmale sterile(TGMS)rice selected from irradiated seeds of Peiai 64S by 350 Gy^(60)Coγ-ray.The aim of the study was to confirm GA3 spraying dosage of Changxuan 3S with eui gene in its hybrid seed production.[Method] Changxuan 3S possessing eui gene and its parent Peiai 64S were chosen as materials.Comparison studies on sensitivity to GA3 in their hybrid seed production were carried out.[Result] The suitable stage for spraying GA3 in the hybrid seed production of Changxuan 3S was at 10% of panicles headed;The optimal dosage was 90 g/hm2 with 2 split sprayings,the first spraying of 45 g/hm2 at heading of 10% panicles and the second one of 45 g/hm2 on the following day.Under the condition of spraying GA3 at the rate of 90 g/hm2,the panicle neck exsertions of Changxuan 3S was +1.78 cm,and exserted stigma rate and seed setting rate of Changxuan 3S were 96.87% and 36.44%,being 21.46% and 16.33% more than those of Peiai 64S,respectively.The theoretical yield of "Changxuan 3S/9311" reached 2 931.90 kg/hm2,which was increased by 1 259.40 kg/hm2 comparing with "Peiai 64S/9311".[Conclusion] Compared with Peiai 64S,Changxuan 3S is more sensitive to GA3,which results in no or little using GA3 in seed production of Changxuan 3S.Moreover,Changxuan 3S showed higher yield potential than Peiai 64S.展开更多
The research introduced the flowchart of organic-material and plant seeds spraying and a case of "Dasi" Highway, the highway from Daxing to Sinan in Guizhou Province, a part of a National Highway from Hang...The research introduced the flowchart of organic-material and plant seeds spraying and a case of "Dasi" Highway, the highway from Daxing to Sinan in Guizhou Province, a part of a National Highway from Hangzhou to Ruili, cal ed Hangrui Highway, slope protection. The flowchart included slope cleaning, net preparation, anchor fixation, adding vegetation-growth plate, spraying organic materi-als, coverage of non-woven fabrics, and maintenance. The technique is proved much efficient in protecting and greening road sideslopes consisting of weathered rocks or hard rocks, which provides a solution for abrupt slope greening technology.展开更多
CuI thin films with nano-scale grains of about 35nm were deposited via spraying method with using acetonitrile as solvent. The influence of iodine doping concentration in acetonitrile solution on the structure, topogr...CuI thin films with nano-scale grains of about 35nm were deposited via spraying method with using acetonitrile as solvent. The influence of iodine doping concentration in acetonitrile solution on the structure, topographic and optical properties of CuI thin films was investigated. X-ray diffraction results showed that CuI iodine-doped films doped CuI:I2 were in γ-phase of zinc blende structure with (111) preferential plane. Scanning electron microscopy revealed that the microstructure of CuI films depended on the relative amount of doping iodine in the solution. When the iodine doping amount in acetonitrile solution was 0.025 g, the film was uniform and compact, the optical transmittance was 75.4% in the part of visible region and the energy band gap was close to 2.96 eV.展开更多
Simulation of the drying process in a top spraying fluidized bed is conducted.A wetting coefficient describing the wetted part of the particle surface is introduced.Using experimental data and the data regression met...Simulation of the drying process in a top spraying fluidized bed is conducted.A wetting coefficient describing the wetted part of the particle surface is introduced.Using experimental data and the data regression method,the modified function of the wetting coefficient is calculated.And this function is introduced to the mathematical model,which describes the heat and mass transfer process in a liquid sprayed gas fluidized bed.Through modeling,the gas humidity and temperature profiles as well as the particle temperature profile can be obtained.Compared with the experimental results,the wetting coefficient and the mathematical model are verified.展开更多
[Objective] This study aimed to investigate the effect of ALA applied by foliage spraying and root irrigation on banana plantlets exposed to cold stress. [Method] After applied by foliage spraying and root irrigation ...[Objective] This study aimed to investigate the effect of ALA applied by foliage spraying and root irrigation on banana plantlets exposed to cold stress. [Method] After applied by foliage spraying and root irrigation with 5-aminolevulinic acid (ALA) at four different concentrations, "Brazil banana" plantlets were placed in artificial climate boxes at 7 ℃ to imitate low-temperature stress. [Result] The results showed that ALA application by both foliage spraying and root application can significantly increase SOD and POD activities, and reduce O2- generation rate, MDA content and relative conductivity in leaves of banana plantlets, as well as raising proline content, soluble protein content and relative water content, and maintaining the stability of chlorophyll. Foliage application of ALA within concentration range of 0.505.00 mg/L had best effect, which increased the chlorophyll content and reduced the relative conductivity and MDA content significantly compared to root irrigation at the same concentration, and raised SOD and POD activities by 64.5% and 12.3% respectively at 5 mg/L compared to their counterparts by root irrigation. [Conclusion] Foliage spraying of ALA can better mitigate the injuries to banana plantlets caused by low-temperature stress.展开更多
This paper presents a new Pulse Width Modulation (PWM) controller for Unmanned Aerial Vehicle (UAV) precisionsprayer for agriculture using a TL494 fixed-frequency pulse width modulator together with a data acquisition...This paper presents a new Pulse Width Modulation (PWM) controller for Unmanned Aerial Vehicle (UAV) precisionsprayer for agriculture using a TL494 fixed-frequency pulse width modulator together with a data acquisition board and developedsoftware. An UAV can be remotely controlled or flown autonomously by pre-programmed flight plans. The PWMcontroller was implemented through the guidance system on the UAV with control commands sent between the UAV helicopterand the ground control station via a wireless telemetry system. The PWM controller was tested and validated using LabVIEW8.2. Several analyses were performed in a laboratory to test different control signals. The results show that the PWM controllerhas promise as a higher precision technique for spray applications, which will improve efficiency of pesticide application,especially in crop production areas.展开更多
The kiwifruit trees(Actinidia deliciosa cv.Bruno)were sprayed with 5 mmol L-1 oxalic acid(OA)or water(as control)at 130,137 or 144 d after full-blossom,and then the fruit were harvested at commercial maturity and stor...The kiwifruit trees(Actinidia deliciosa cv.Bruno)were sprayed with 5 mmol L-1 oxalic acid(OA)or water(as control)at 130,137 or 144 d after full-blossom,and then the fruit were harvested at commercial maturity and stored at room temperature(20±1)℃ for 13 d.The effect of pre-harvest spraying of OA on postharvest quality of kiwifruit was evaluated during storage.The OA spraying slowed the increase in soluble solids content(SSC)and decrease in titratable acid(TA),as well as increased contents of ascorbic acid(AsA)and total-AsA accompanied with higher AsA/DHA ratio in kiwifruit during storage.Moreover,the OA spraying significantly reduced the contents of acetaldehyde and ethanol in kiwifruit,along with significant decrease in activities of enzymes involved in ethanol fermentation metabolism during the later period of storage,which was beneficial to control off-flavor associated with over accumulation of ethanol during postharvest.It was suggested that pre-harvest spraying of OA might maintain the postharvest quality of kiwifruit in relation to delay in fruit ripening,AsA maintenance and regulation of ethanol fermentation.展开更多
Fe/Mo composite coatings were prepared by air plasma spraying (APS) using Fe-based and Mo-based amorphous and nanocrys- talline mixed powders. Microstructural studies show that the composite coatings present a layer...Fe/Mo composite coatings were prepared by air plasma spraying (APS) using Fe-based and Mo-based amorphous and nanocrys- talline mixed powders. Microstructural studies show that the composite coatings present a layered structure with low porosity due to adding the self-bonded Mo-based alloy. Corrosion behaviors of the composite coatings, the Fe-based coatings and the Mo-based coatings were in- vestigated by electrochemical measurements and salt spray tests. Electrochemical results show that the composite coatings exhibit a lower polarization current density and higher corrosion potentials than the Fe-based coating when tested in 3.5wt% NaC1 solutions, indicating supe- rior corrosion resistance compared with the Fe-based coating. Also with the increase in addition of the Mo-based alloy, a raised corrosion re- sistance, inferred by an increase in corrosion potential and a decrease in polarization current density, can be found. The results of salt spray tests again show that the corrosion resistance is enhanced by adding the Mo-based alloy, which helps to reduce the porosity of the composite coatings and enhance the stability of the passive films.展开更多
A nanostructured thermal barrier coating is prepared by air plasma spraying using the 8wt% Y_2O_3 partially stabilized zirconia nano-powder with an average grain size of 40 nm. The microstructure and phase composition...A nanostructured thermal barrier coating is prepared by air plasma spraying using the 8wt% Y_2O_3 partially stabilized zirconia nano-powder with an average grain size of 40 nm. The microstructure and phase composition of feedstock nano-powder and coating are investigated using SEM, TEM and XRD. It is found that the as-sprayed zirconia coating has an average grain size of 67 nm and mainly consistes of metastable tetragonal phase, together with some monoclinic phase and tetragonal phase. Thermal treatment results show that the grains of the nanostructured coating grow slightly below 900℃, whereas over 1000℃ the gains grow rapidly and monoclinic phase noticeably appeares.展开更多
Effective removal of adhesive and fine dusts from flue gas is very difficult. A new method of electrostatic precipitation of the corona discharges with spraying water(CDSW) was introduced. A new electrode configuratio...Effective removal of adhesive and fine dusts from flue gas is very difficult. A new method of electrostatic precipitation of the corona discharges with spraying water(CDSW) was introduced. A new electrode configuration and the circulation spraying of water were employed in the method. The efficient electrostatic precipitation for adhesive and fine dusts can be accomplished without any drain water during a long operating period. The fundamental structure, discharge characteristics, mechanism of spraying and precipitation principle of the electrostatic precipitation using CDSW were described and analyzed. The V I characteristics, spraying state, supplying water quantity, influence of temperature and clean of the electrodes were researched in series experiments. The treating effects of circulating spraying using the corona plasma at the same time of electrostatic precipitation were investigated. The fundamental theories and experimental data were proposed, in order to effectively remove the adhesive dusts from flue gas using CDSW in practice.展开更多
According to the working condition of boiler tubes of power station, hot corrosion tests were carried out at two temperatures (650℃ and 800℃) to simulate the environment of coal fired boiler. The hot corrosion resis...According to the working condition of boiler tubes of power station, hot corrosion tests were carried out at two temperatures (650℃ and 800℃) to simulate the environment of coal fired boiler. The hot corrosion resistance and mechanism of three arc spraying coatings (SL30, 45CT and FeCrAl) have been studied. The result showed that coating SL30 and 45CT have a better protection ability against hot corrosion. It indicated that a protective Cr 2O 3 scale formed on the surface of coating SL30 and coating 45CT.展开更多
In the practical cold-spraying process, a number of particles impact onto a substrate and then form a coating. To study the deformation behavior and multi-particle interactions, single-particle, two-particle, and thre...In the practical cold-spraying process, a number of particles impact onto a substrate and then form a coating. To study the deformation behavior and multi-particle interactions, single-particle, two-particle, and three-particle impacts were simulated using the ANSYS/LS-DYNA version 970. A copper coating was prepared and scanning electron microscopy (SEM) was employed to analyze the microstructures of the powders and the coating. Numerical results reveal that the critical deposition velocity is 600 m/s for a copper particle/copper substrate. The particles deform more fully due to multi-particle interactions, such as tamping, interlocking, and extrusion effects. The compression ratio increases from 40% to 70% as a result of the tamping effect. This is beneficial for achieving the cold-sprayed coating. The multi-particle morphology and compression ratio in the experiment are consistent with those of simulation results. Based on these results, the coating of high performance can be prepared through selecting appropriate parameters and suitable pre-treatment processes.展开更多
The robust magnesium surfaces with multi-functions are highly desirable,and the simple and scalable methods to construct such surfaces are urgently indispensable.Herein,we conducted a one-step spraying method to facil...The robust magnesium surfaces with multi-functions are highly desirable,and the simple and scalable methods to construct such surfaces are urgently indispensable.Herein,we conducted a one-step spraying method to facilely fabricate the robust coating with multi-functions on magnesium alloys.The as-sprayed magnesium alloys surface is superhydrophobic with a static water contact angle(WCA)of 157.0°and a roll-off angle of 6.0°.Such surface has excellent mechanical,chemical and thermal stabilities,even undergoing various physical and chemical damages,including sand impact(10 gmin^(-1),≥20 min),water impact(2 impacts s^(-1),≥180 min),abrasion(1.00 kPa,≥25 cycles),peeling(≥2.15 kPa),high temperature(200°C,≥24 h),strong acidic/salty/basic media(p H=113)and organic-solvent immersion(ethanol and n-hexane,≥24 h),demonstrating brilliant robustness.Notably,the surface displays multi-functions of corrosion protection,anti-fouling and heat insulation,which will undoubtedly promote the much wider applications of magnesium alloys.展开更多
In order to produce the hear-resistant inner layer of hot-forging die, the plasma spraying and plasma re-melting and plasma spray welding were adopted. Substrate material was W6Mo5Cr4V2, including 10%, 20%, 30% tungst...In order to produce the hear-resistant inner layer of hot-forging die, the plasma spraying and plasma re-melting and plasma spray welding were adopted. Substrate material was W6Mo5Cr4V2, including 10%, 20%, 30% tungsten carbide (WC) ceramic powder used as coating material to obtain different Nickel-based WC alloys coating. Micro-structure and micro-hardness analysis of the coating layer are conducted, as well as thermophysical properties for the coating layer were measured. The experimental results show that the coating prepared with 70%Ni60, 30%WC powder has the best properties with plasma spray welding, in which the micro-hardness can achieve 900HV, meanwhile it can improve the thermal property of hot-forging die dramatically.展开更多
Nanostructured and conventional Al2O3-13wt.%TiO2 ceramic coatings were prepared by plasma spraying with nanostructured agglomerated and conventional powders, respectively. The microstructure and microhardness of the c...Nanostructured and conventional Al2O3-13wt.%TiO2 ceramic coatings were prepared by plasma spraying with nanostructured agglomerated and conventional powders, respectively. The microstructure and microhardness of the coatings were investigated using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and microhardness measurement. Meanwhile, the friction and wear behaviors were analyzed and compared using a ball-on-disk tribometer. The results show that the conventional coating has lamellar stacking characteristic and has some pores. However, the nanostructured coating shows a bimodal microstructure, which is composed of both fully melted regions and partially melted regions. According to the microstructural difference, the partially melted regions can be divided into liquid-phase sintered regions (a three-dimensional net or skeleton-like structure: Al2O3-rich submicron particles embedded in the TiO2-rich matrix) and solid-phase sintered regions (remained nanoparticles). The microstructural characteristics of the liquid-phase sintered region are formed due to the selective melting of TiO2 nanoparticles during plasma spraying. On the other hand, the TiO2 and Al2O3 nanoparticles of the solid-phase sintered regions are all unmelted during plasma spraying. Due to the existence of nanostructured microstructures, the nanostructured coating has a higher microhardness, a lower friction coefficient, and a better wear resistance than the conventional coating.展开更多
In order to improve the in-flight characteristics of the atomizing droplets during high velocity wire arc spraying (HVAS), some changes have been operated on the original design of the HVAS gun configuration. A compar...In order to improve the in-flight characteristics of the atomizing droplets during high velocity wire arc spraying (HVAS), some changes have been operated on the original design of the HVAS gun configuration. A comparative study was carried out to investigate the microstructure and properties of the coatings produced by the original design spraying gun and the modified one, using 3Cr13 wires of 3 mm in diameter. The characteristics of their jets were examined during spraying. The results indicate that, the included angle between the two wires and the distance from the nozzle to the meeting point of the two vires may have a strong influence on the characteristics of the in-flight droplets and then the coatings. The jet divergence is found to be lower than that of the original one (about 12° against 25°). By modified gun, the adhesion strength, the microhardness and porosity of the coating deposited by modified gun are increased by 39% and 9% respectively. And the porosity of the coatings is decreased by 57%.展开更多
基金Supported by National Natural Science Foundation of China(Grant Nos.52175411 and 51205177)Jiangsu Provincial Natural Science Foundation(Grant Nos.BK20171307 and BK2012277).
文摘The current study of minimum quantity lubrication(MQL)concentrates on its performance improvement.By contrast with nanofluid MQL and electrostatic atomization(EA),the proposed nanofluid composite electrostatic spraying(NCES)can enhance the performance of MQL more comprehensively.However,it is largely influenced by the base fluid of external fluid.In this paper,the lubrication property and machining performance of NCES with different types of vegetable oils(castor,palm,soybean,rapeseed,and LB2000 oil)as the base fluids of external fluid were compared and evaluated by friction and milling tests under different flow ratios of external and internal fluids.The spraying current and electrowetting angle were tested to analyze the influence of vegetable oil type as the base fluid of external fluid on NCES performances.The friction test results show that relative to NCES with other vegetable oils as the base fluids of external fluid,NCES with LB2000 as the base fluid of external fluid reduced the friction coefficient and wear loss by 9.4%-27.7%and 7.6%-26.5%,respectively.The milling test results display that the milling force and milling temperature for NCES with LB2000 as the base fluid of external fluid were 1.4%-13.2%and 3.6%-11.2%lower than those for NCES with other vegetable oils as the base fluids of external fluid,respectively.When LB2000/multi-walled carbon nanotube(MWCNT)water-based nanofluid was used as the external/internal fluid and the flow ratio of external and internal fluids was 2:1,NCES showed the best milling performance.This study provides theoretical and technical support for the selection of the base fluid of NCES external fluid.
文摘The technology for spraying a sintering bed and thus improving sinter quality indicators while reducing the emission of flue gas pollutants has recently become an important research topic.The impacts on sinter quality and emissions when spraying the sintering surface with different amounts and flow rates of steam were investigated in this study.The sinter quality indicators were most effectively improved by spraying 180 g of steam flow continuously at a rate of 0.02 m^(3)/min for 15 min after ignition for 8 min.The optimal effect on emission reduction was obtained by spraying 90 g of steam flow continuously at a rate of 0.01 m^(3)/min for 15 min after ignition for 8 min.
基金Project(EA201103238)supported by Nanchang Hangkong University Doctor Startup Fund,China
文摘The Fe-based amorphous metallic matrix coating (Fe-AMMC) was fabricated with the powder mixtures of Fe-based metallic glass synthesized with industrial raw materials, NiCr alloy and WC particle by high velocity oxy-fuel (HVOF) spraying. The corrosion resistance of Fe-AMMC was investigated by potentiodynamic polarization tests in 1 mol/L HCl, NaCl, H2SO4 and NaOH solutions, respectively. The surface morphologies corroded were observed by SEM. The results indicate that Fe-AMMC exhibits excellent corrosion resistance, higher corrosion resistance than 304L stainless steel in the chloride solutions. The low corrosion current density and passive current density of Fe-AMMC with a wide spontaneous passivation region are about 132.0μA/cm2 and 9.0 mA/cm2 in HCl solution, and about 2.5 μA/cm2 and 2.3 mA/cm2 in NaCl solution. The excellent corrosion resistance demonstrates that Fe-based amorphous metallic matrix powder is a viable engineering material in practical anti-corrosion and anti-wear coating applications.
基金Supported by Special Fund for S&R in the Public Interest(200903007)Special Fund in the Public Interest(201203013)Henan Key Project(102101110200)~~
文摘In order to explore the effect of spraying fertilizers after flowering on grain weight and nutritional quality of different winter wheat cultivars, twenty wheat culti- vars in wheat zones along Yellow River and Huai River, were used to investigate the change of thousand kernel weight (TKW), phytic acid content (PAC), contents of Fe, Zn and Mg and bioavailability by spraying zinc and nitrogen fertilizers after flowering. The results showed that both of TKW and protein content in grains in- creased by spraying Zn and N fertilizers, and the effect of N fertilizer proved more significant. The PAC decreased significantly after Zn treatment, for example, PAC of "955159", a wheat cultivar, decreased by 27.95%. However, PAC was in- significantly influenced by N fertilizer. On the other hand, Zn content in wheat grains were improved after spraying Zn fertilizer and the increase aveaged 54.38%. Furthermore, Fe and Zn contents grew significantly after spraying N fertilizer, and the increase averaged 36.88% and 11.25% respectively. However, Mg content in grains declined by N fertilizer. Still, the bioavailability of zinc in grains was enhanced after spraying Zn fertilizer, and of Fe was also increased greatly after spraying N fertilizer. In conclusion, grain weight, and content and effectiveness of mineral ele-ments can be improved simultaneously by rational spraying of N and Zn fertilizers to improve quality of grains.
基金Supported by Technology Research and Development Program of Hunan Provincial Science&Technology Department(2008FJ3066)Study on Hormones Regulation of Uppermost Internode Elongation of Eui Tgms Rice Changxuan 3S and GA3 Spraying Dosoge in ItsHybrid Seed Production,Key Program of Hunan Provincial Department of Education(09A066)+1 种基金Natural Science Foundation of Hunan Province(07JJ6032)Study on Expansion Inuppermost Internode of Rice Male Sterile Line with Eui Geng~~
文摘[Objective] Changxuan 3S was thermo-sensitive genicmale sterile(TGMS)rice selected from irradiated seeds of Peiai 64S by 350 Gy^(60)Coγ-ray.The aim of the study was to confirm GA3 spraying dosage of Changxuan 3S with eui gene in its hybrid seed production.[Method] Changxuan 3S possessing eui gene and its parent Peiai 64S were chosen as materials.Comparison studies on sensitivity to GA3 in their hybrid seed production were carried out.[Result] The suitable stage for spraying GA3 in the hybrid seed production of Changxuan 3S was at 10% of panicles headed;The optimal dosage was 90 g/hm2 with 2 split sprayings,the first spraying of 45 g/hm2 at heading of 10% panicles and the second one of 45 g/hm2 on the following day.Under the condition of spraying GA3 at the rate of 90 g/hm2,the panicle neck exsertions of Changxuan 3S was +1.78 cm,and exserted stigma rate and seed setting rate of Changxuan 3S were 96.87% and 36.44%,being 21.46% and 16.33% more than those of Peiai 64S,respectively.The theoretical yield of "Changxuan 3S/9311" reached 2 931.90 kg/hm2,which was increased by 1 259.40 kg/hm2 comparing with "Peiai 64S/9311".[Conclusion] Compared with Peiai 64S,Changxuan 3S is more sensitive to GA3,which results in no or little using GA3 in seed production of Changxuan 3S.Moreover,Changxuan 3S showed higher yield potential than Peiai 64S.
文摘The research introduced the flowchart of organic-material and plant seeds spraying and a case of "Dasi" Highway, the highway from Daxing to Sinan in Guizhou Province, a part of a National Highway from Hangzhou to Ruili, cal ed Hangrui Highway, slope protection. The flowchart included slope cleaning, net preparation, anchor fixation, adding vegetation-growth plate, spraying organic materi-als, coverage of non-woven fabrics, and maintenance. The technique is proved much efficient in protecting and greening road sideslopes consisting of weathered rocks or hard rocks, which provides a solution for abrupt slope greening technology.
基金Project (2091003) supported by Beijing Natural Science Foundation, China
文摘CuI thin films with nano-scale grains of about 35nm were deposited via spraying method with using acetonitrile as solvent. The influence of iodine doping concentration in acetonitrile solution on the structure, topographic and optical properties of CuI thin films was investigated. X-ray diffraction results showed that CuI iodine-doped films doped CuI:I2 were in γ-phase of zinc blende structure with (111) preferential plane. Scanning electron microscopy revealed that the microstructure of CuI films depended on the relative amount of doping iodine in the solution. When the iodine doping amount in acetonitrile solution was 0.025 g, the film was uniform and compact, the optical transmittance was 75.4% in the part of visible region and the energy band gap was close to 2.96 eV.
文摘Simulation of the drying process in a top spraying fluidized bed is conducted.A wetting coefficient describing the wetted part of the particle surface is introduced.Using experimental data and the data regression method,the modified function of the wetting coefficient is calculated.And this function is introduced to the mathematical model,which describes the heat and mass transfer process in a liquid sprayed gas fluidized bed.Through modeling,the gas humidity and temperature profiles as well as the particle temperature profile can be obtained.Compared with the experimental results,the wetting coefficient and the mathematical model are verified.
基金Supported by the National Natural Science Foundation of China (30860170)Fund for the Youth of Hainan University(qujj1160)~~
文摘[Objective] This study aimed to investigate the effect of ALA applied by foliage spraying and root irrigation on banana plantlets exposed to cold stress. [Method] After applied by foliage spraying and root irrigation with 5-aminolevulinic acid (ALA) at four different concentrations, "Brazil banana" plantlets were placed in artificial climate boxes at 7 ℃ to imitate low-temperature stress. [Result] The results showed that ALA application by both foliage spraying and root application can significantly increase SOD and POD activities, and reduce O2- generation rate, MDA content and relative conductivity in leaves of banana plantlets, as well as raising proline content, soluble protein content and relative water content, and maintaining the stability of chlorophyll. Foliage application of ALA within concentration range of 0.505.00 mg/L had best effect, which increased the chlorophyll content and reduced the relative conductivity and MDA content significantly compared to root irrigation at the same concentration, and raised SOD and POD activities by 64.5% and 12.3% respectively at 5 mg/L compared to their counterparts by root irrigation. [Conclusion] Foliage spraying of ALA can better mitigate the injuries to banana plantlets caused by low-temperature stress.
文摘This paper presents a new Pulse Width Modulation (PWM) controller for Unmanned Aerial Vehicle (UAV) precisionsprayer for agriculture using a TL494 fixed-frequency pulse width modulator together with a data acquisition board and developedsoftware. An UAV can be remotely controlled or flown autonomously by pre-programmed flight plans. The PWMcontroller was implemented through the guidance system on the UAV with control commands sent between the UAV helicopterand the ground control station via a wireless telemetry system. The PWM controller was tested and validated using LabVIEW8.2. Several analyses were performed in a laboratory to test different control signals. The results show that the PWM controllerhas promise as a higher precision technique for spray applications, which will improve efficiency of pesticide application,especially in crop production areas.
基金the financial support provided by the National Natural Science Foundation of China (31671908)the National Key Research and Development Program of China (2016YFD0400901)
文摘The kiwifruit trees(Actinidia deliciosa cv.Bruno)were sprayed with 5 mmol L-1 oxalic acid(OA)or water(as control)at 130,137 or 144 d after full-blossom,and then the fruit were harvested at commercial maturity and stored at room temperature(20±1)℃ for 13 d.The effect of pre-harvest spraying of OA on postharvest quality of kiwifruit was evaluated during storage.The OA spraying slowed the increase in soluble solids content(SSC)and decrease in titratable acid(TA),as well as increased contents of ascorbic acid(AsA)and total-AsA accompanied with higher AsA/DHA ratio in kiwifruit during storage.Moreover,the OA spraying significantly reduced the contents of acetaldehyde and ethanol in kiwifruit,along with significant decrease in activities of enzymes involved in ethanol fermentation metabolism during the later period of storage,which was beneficial to control off-flavor associated with over accumulation of ethanol during postharvest.It was suggested that pre-harvest spraying of OA might maintain the postharvest quality of kiwifruit in relation to delay in fruit ripening,AsA maintenance and regulation of ethanol fermentation.
基金financially supported by the Special Fund for Basic Scientific Research of Central Colleges, Chang’an University (No.CHD2011JC126)the Special Fund for Basic Research Support Plan of Chang’an Universitythe Open Fund of the Engineering Research Center of Transportation Materials, Ministry of Education of China
文摘Fe/Mo composite coatings were prepared by air plasma spraying (APS) using Fe-based and Mo-based amorphous and nanocrys- talline mixed powders. Microstructural studies show that the composite coatings present a layered structure with low porosity due to adding the self-bonded Mo-based alloy. Corrosion behaviors of the composite coatings, the Fe-based coatings and the Mo-based coatings were in- vestigated by electrochemical measurements and salt spray tests. Electrochemical results show that the composite coatings exhibit a lower polarization current density and higher corrosion potentials than the Fe-based coating when tested in 3.5wt% NaC1 solutions, indicating supe- rior corrosion resistance compared with the Fe-based coating. Also with the increase in addition of the Mo-based alloy, a raised corrosion re- sistance, inferred by an increase in corrosion potential and a decrease in polarization current density, can be found. The results of salt spray tests again show that the corrosion resistance is enhanced by adding the Mo-based alloy, which helps to reduce the porosity of the composite coatings and enhance the stability of the passive films.
文摘A nanostructured thermal barrier coating is prepared by air plasma spraying using the 8wt% Y_2O_3 partially stabilized zirconia nano-powder with an average grain size of 40 nm. The microstructure and phase composition of feedstock nano-powder and coating are investigated using SEM, TEM and XRD. It is found that the as-sprayed zirconia coating has an average grain size of 67 nm and mainly consistes of metastable tetragonal phase, together with some monoclinic phase and tetragonal phase. Thermal treatment results show that the grains of the nanostructured coating grow slightly below 900℃, whereas over 1000℃ the gains grow rapidly and monoclinic phase noticeably appeares.
文摘Effective removal of adhesive and fine dusts from flue gas is very difficult. A new method of electrostatic precipitation of the corona discharges with spraying water(CDSW) was introduced. A new electrode configuration and the circulation spraying of water were employed in the method. The efficient electrostatic precipitation for adhesive and fine dusts can be accomplished without any drain water during a long operating period. The fundamental structure, discharge characteristics, mechanism of spraying and precipitation principle of the electrostatic precipitation using CDSW were described and analyzed. The V I characteristics, spraying state, supplying water quantity, influence of temperature and clean of the electrodes were researched in series experiments. The treating effects of circulating spraying using the corona plasma at the same time of electrostatic precipitation were investigated. The fundamental theories and experimental data were proposed, in order to effectively remove the adhesive dusts from flue gas using CDSW in practice.
文摘According to the working condition of boiler tubes of power station, hot corrosion tests were carried out at two temperatures (650℃ and 800℃) to simulate the environment of coal fired boiler. The hot corrosion resistance and mechanism of three arc spraying coatings (SL30, 45CT and FeCrAl) have been studied. The result showed that coating SL30 and 45CT have a better protection ability against hot corrosion. It indicated that a protective Cr 2O 3 scale formed on the surface of coating SL30 and coating 45CT.
基金supported by the National Natural Science Foundation of China (Nos.50871019 and 50874009)the National Superiority Discipline Innovation Platform Project (SKL-AMM-CS)
文摘In the practical cold-spraying process, a number of particles impact onto a substrate and then form a coating. To study the deformation behavior and multi-particle interactions, single-particle, two-particle, and three-particle impacts were simulated using the ANSYS/LS-DYNA version 970. A copper coating was prepared and scanning electron microscopy (SEM) was employed to analyze the microstructures of the powders and the coating. Numerical results reveal that the critical deposition velocity is 600 m/s for a copper particle/copper substrate. The particles deform more fully due to multi-particle interactions, such as tamping, interlocking, and extrusion effects. The compression ratio increases from 40% to 70% as a result of the tamping effect. This is beneficial for achieving the cold-sprayed coating. The multi-particle morphology and compression ratio in the experiment are consistent with those of simulation results. Based on these results, the coating of high performance can be prepared through selecting appropriate parameters and suitable pre-treatment processes.
基金supported by the National Natural Science Foundation of China(21773019,21972012)the Graduate Research and Innovation Foundation of Chongqing(CYB18044)the sharing fund of Chongqing University s Large-scale Equipment
文摘The robust magnesium surfaces with multi-functions are highly desirable,and the simple and scalable methods to construct such surfaces are urgently indispensable.Herein,we conducted a one-step spraying method to facilely fabricate the robust coating with multi-functions on magnesium alloys.The as-sprayed magnesium alloys surface is superhydrophobic with a static water contact angle(WCA)of 157.0°and a roll-off angle of 6.0°.Such surface has excellent mechanical,chemical and thermal stabilities,even undergoing various physical and chemical damages,including sand impact(10 gmin^(-1),≥20 min),water impact(2 impacts s^(-1),≥180 min),abrasion(1.00 kPa,≥25 cycles),peeling(≥2.15 kPa),high temperature(200°C,≥24 h),strong acidic/salty/basic media(p H=113)and organic-solvent immersion(ethanol and n-hexane,≥24 h),demonstrating brilliant robustness.Notably,the surface displays multi-functions of corrosion protection,anti-fouling and heat insulation,which will undoubtedly promote the much wider applications of magnesium alloys.
基金Funded by the National Natural Science Foundation of China(No.50675165)the National Key Technology R&D Program(No.2006BAF02A29)
文摘In order to produce the hear-resistant inner layer of hot-forging die, the plasma spraying and plasma re-melting and plasma spray welding were adopted. Substrate material was W6Mo5Cr4V2, including 10%, 20%, 30% tungsten carbide (WC) ceramic powder used as coating material to obtain different Nickel-based WC alloys coating. Micro-structure and micro-hardness analysis of the coating layer are conducted, as well as thermophysical properties for the coating layer were measured. The experimental results show that the coating prepared with 70%Ni60, 30%WC powder has the best properties with plasma spray welding, in which the micro-hardness can achieve 900HV, meanwhile it can improve the thermal property of hot-forging die dramatically.
基金supported by the National Natural Science Foundation of China (Nos. 59975046 and 50305010)the Key Natural Science Foundation of Ji-angsu Province, China (No. BK2004005)
文摘Nanostructured and conventional Al2O3-13wt.%TiO2 ceramic coatings were prepared by plasma spraying with nanostructured agglomerated and conventional powders, respectively. The microstructure and microhardness of the coatings were investigated using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and microhardness measurement. Meanwhile, the friction and wear behaviors were analyzed and compared using a ball-on-disk tribometer. The results show that the conventional coating has lamellar stacking characteristic and has some pores. However, the nanostructured coating shows a bimodal microstructure, which is composed of both fully melted regions and partially melted regions. According to the microstructural difference, the partially melted regions can be divided into liquid-phase sintered regions (a three-dimensional net or skeleton-like structure: Al2O3-rich submicron particles embedded in the TiO2-rich matrix) and solid-phase sintered regions (remained nanoparticles). The microstructural characteristics of the liquid-phase sintered region are formed due to the selective melting of TiO2 nanoparticles during plasma spraying. On the other hand, the TiO2 and Al2O3 nanoparticles of the solid-phase sintered regions are all unmelted during plasma spraying. Due to the existence of nanostructured microstructures, the nanostructured coating has a higher microhardness, a lower friction coefficient, and a better wear resistance than the conventional coating.
基金Project (50235030) supported by the National Natural Science Foundation of China
文摘In order to improve the in-flight characteristics of the atomizing droplets during high velocity wire arc spraying (HVAS), some changes have been operated on the original design of the HVAS gun configuration. A comparative study was carried out to investigate the microstructure and properties of the coatings produced by the original design spraying gun and the modified one, using 3Cr13 wires of 3 mm in diameter. The characteristics of their jets were examined during spraying. The results indicate that, the included angle between the two wires and the distance from the nozzle to the meeting point of the two vires may have a strong influence on the characteristics of the in-flight droplets and then the coatings. The jet divergence is found to be lower than that of the original one (about 12° against 25°). By modified gun, the adhesion strength, the microhardness and porosity of the coating deposited by modified gun are increased by 39% and 9% respectively. And the porosity of the coatings is decreased by 57%.