The geometry of an inductively coupled plasma (ICP) etcher is usually considered to be an important factor for determining both plasma and process uniformity over a large wafer. During the past few decades, these pa...The geometry of an inductively coupled plasma (ICP) etcher is usually considered to be an important factor for determining both plasma and process uniformity over a large wafer. During the past few decades, these parameters were determined by the "trial and error" method, resulting in wastes of time and funds. In this paper, a new approach of regression orthogonal design with plasma simulation experiments is proposed to investigate the sensitivity of the structural parameters on the uniformity of plasma characteristics. The tool for simulating plasma is CFD-ACE+, which is commercial multi-physical modeling software that has been proven to be accurate for plasma simulation. The simulated experimental results are analyzed to get a regression equation on three structural parameters. Through this equation, engineers can compute the uniformity of the electron number density rapidly without modeling by CFD-ACE+. An optimization performed at the end produces good results.展开更多
The thermal induced errors can account for as much as 70% of the dimensional errors on a workpiece. Accurate modeling of errors is an essential part of error compensation. Base on analyzing the existing approaches of ...The thermal induced errors can account for as much as 70% of the dimensional errors on a workpiece. Accurate modeling of errors is an essential part of error compensation. Base on analyzing the existing approaches of the thermal error modeling for machine tools, a new approach of regression orthogonal design is proposed, which combines the statistic theory with machine structures, surrounding condition, engineering judgements, and experience in modeling. A whole computation and analysis procedure is given. Therefore, the model got from this method are more robust and practical than those got from the present method that depends on the modeling data completely. At last more than 100 applications of CNC turning center with only one thermal error model are given. The cutting diameter variation reduces from more than 35 μm to about 12 μm with the orthogonal regression modeling and compensation of thermal error.展开更多
In this paper, the influence of plasma arc powder surfacing technical parameters on the property of layer is defined using the orthogonal design. By the orthogonal polynomial regression, when plasma arc powder surfaci...In this paper, the influence of plasma arc powder surfacing technical parameters on the property of layer is defined using the orthogonal design. By the orthogonal polynomial regression, when plasma arc powder surfacing is used on the surface of the X65 steel plate with the Fe-07 alloy powder, the optimum technical parameters are the following: I=180~190 A , G=41.5 g/min , v=102 mm/min , T_0=350 ℃ , Q_l=280 L/h , Q_s=400 L/h . Further, analysis of the cracking test data showed that the cracking preheat temperature is 350 ℃ .展开更多
A three levels orthogonal table-L9(34) was used,namely,impact angle,rotating speed,erodent size,and surface configuration were considered.The three bionic surface configurations are pit,groove,and ring.The experimen...A three levels orthogonal table-L9(34) was used,namely,impact angle,rotating speed,erodent size,and surface configuration were considered.The three bionic surface configurations are pit,groove,and ring.The experimental results indicate the experiment factors affecting erosive rate are,in their sequence of contribution,erodent size,impact angle,configuration,and rotating speed;the erosive rate increased with increase in rotating speed,erodent size;the erosion resistance of the sample with ring structure is higher than that of the other two samples.Based on this result,regression orthogonal experiment was carried out to select the optimal erosion resistance condition with respect to the ring bionic surface configuration.Regression equations between erosive rate and experimental factors of ring surface configurations were obtained.展开更多
Background:Blood stasis syndrome is one of the major syndromes in the development of chronic conditions in traditional Chinese medicine.Blood stasis syndrome is closely related to microcirculation dysfunction and thro...Background:Blood stasis syndrome is one of the major syndromes in the development of chronic conditions in traditional Chinese medicine.Blood stasis syndrome is closely related to microcirculation dysfunction and thrombosis.Trigonaceae,as a representative traditional Chinese medicine for promoting blood circulation and removing blood stasis,there are many studies on its anticoagulant,antiplatelet aggregation and antithrombotic effects.Methods:Optimization of sparganin compounds,comprising sparganin A,sparganin B,and sparganin C for the characterization of drug pair effects against blood stasis syndrome was carried out.Ternary quadratic regression orthogonal combination design was carried out in a mouse model of blood stasis syndrome.The concentrations of thromboxane B2,plasminogen activator inhibitor 1,fibrinogen,and endothelin 1 were evaluated by enzyme linked immunosorbent assay.Thymus,hepatic,and spleen indices were also assessed.The outcomes of the evaluations aided in identifying optimum parameter values for the most favorable precipitation against blood stasis syndrome.Subsequently,Cytoscape 3.7.1 was used for network pharmacology to predict the key targets of sparganins and disease.Results:After sparganin A,sparganin B,and sparganin C treatment,hepatic had a downward trend,while spleen indices and thymus had an upward trend.Compared with the model group,thromboxane B2,endothelin 1,plasminogen activator inhibitor 1,and fibrinogen were decreased(P<0.05).The blood stasis syndrome model regression equation was extremely significant,and the correlation coefficient of R was 0.939,indicating that sparganin A,sparganin B and sparganin C were positively correlated at all levels.According to the dosage of these three factors and test results,the equation was fitted and the maximum values of the three sparganin in the corresponding dose range were obtained as follows:A=0.2982 mg/10g,B=0.1438 mg/10g,C=0.0417 mg/10g.Thus,the optimum parameters were found to be 0.298:0.144:0.042 for synergistic drug combinations of sparganin compounds sparganin A,sparganin B,and sparganin C in blood stasis syndrome.The possible key targets of sparganins included matrix metalloproteinase 9,plasminogen,proto-oncogene tyrosine-protein kinase src,and akt serine/threonine kinase 1 in blood stasis syndrome.Conclusion:Our study for the first time found two novel cyclic peptide compounds sparganin B and sparganin C have an anti-blood stasis effect,and speculated sparganins key targets included matrix metalloproteinase 9,plasminogen,proto-oncogene tyrosine-protein kinase src,and akt serine/threonine kinase 1 in blood stasis syndrome.展开更多
[ Objective] To study the effects of combined application of different elements on alfalfa hay yield. [ Medthod] Potassium sulfate, ammonium chloride, superphosphate and magnesium oxide were applied to alfalfa field i...[ Objective] To study the effects of combined application of different elements on alfalfa hay yield. [ Medthod] Potassium sulfate, ammonium chloride, superphosphate and magnesium oxide were applied to alfalfa field in the experiment, and quaternary quadratic regression orthogonal combination was used to examine the effects of the experiment factors on hay yield of alfalfa. [ Result] The order of targets based on the effects on hay yield is as follows: potassium sulfate 〉 ammonium chloride 〉 magnesium oxide 〉 superphosphate. Among them, the potassium sulfate had a significant impact on alfalfa hay yield. The interaction between potassium sulfate and magnesium oxide also had a significant impact on alfalfa hay yield. [ Conclusion] The optimal cultivation measures for alfalfa hay yield of more than 19 224.6 kg/hm^2 are as follows: potassium sulfate, 163.253 - 181.679 kg/hm^2 ; ammonium chloride, 155.877 - 174.258 kg/hm^2 ; superphosphate, 566.177 - 632.924 kg/hm^2 ; and magnesium oxide, 30.060 - 33.628 kg/hm^2.展开更多
Effects of Mg^2+, NTPs and Taq DNA polymerase in pear SSR-PCR system were analyzed by quadratic regressive orthogonal rotational combinational design. Results showed: absolute IOD (Integrated OD of each band) valu...Effects of Mg^2+, NTPs and Taq DNA polymerase in pear SSR-PCR system were analyzed by quadratic regressive orthogonal rotational combinational design. Results showed: absolute IOD (Integrated OD of each band) value of target band reduced with concentration rising of Mg^2+ and Taq DNA polymerase, but heightened with concentration rising of dNTPs. The decay rate of absolute IOD value increased progressively with rising Mg^2+ concentration, decreased gradually with rising Taq DNA polymerase concentration; the rising speed would be slower than the dNTPs increase. Absolute IOD value would reduce with concentration rising of dNTPs at a low level of Mg^2+ concentration. Conversely it would rise with the increase of dNTPs while high Mg^2+ concentration. Absolute IOD value would generally rise with concentration rising of Taq DNA polymerase while low Mg^2+ concentration. On the contrary it would reduce with concentration rising of Taq DNA polymerase while high Mg^2+ concentration.展开更多
It is found that many biological organisms exhibit superior adhesion characteristics in wet environments. It has been observed that the foot pads of tree frogs and katydids are consist of a number of closely arranged ...It is found that many biological organisms exhibit superior adhesion characteristics in wet environments. It has been observed that the foot pads of tree frogs and katydids are consist of a number of closely arranged polygons, most of them are hexagonal. In this paper, the common structure of two kinds of biological foot pad was extracted to model the bionic surface structure of friction plates. The friction plate prototypes were also prepared. Through the multivariate orthogonal regression design, the optimum parameter combination of the friction performances of the prototypes of the bionic plates has been obtained. The hexagonal circumcircle size is 10 mm, the groove width is 1 mm, and the hexagonal diagonal angle is 90~. Then the maximum static friction coefficient, dynamic friction coefficient and wear amount of the optimal friction plate were tested and compared with the control group friction plates. The comparative analysis of the experiment findings demonstrated that the bionic structure with hexagonal ring grooves can significantly improve the friction performance of the friction plates.展开更多
In order to optimize the pellet induration process parameters of rotary kiln, a mathematical model is developed and solved by using commercial software FLUENT. Orthogonal regression has been performed by using the sim...In order to optimize the pellet induration process parameters of rotary kiln, a mathematical model is developed and solved by using commercial software FLUENT. Orthogonal regression has been performed by using the simulated results of the pellet induration in rotary kiln. The functional relations between pellet induration quality and process parameters are obtained. The main parameters that affect the thermal process are also discussed. The results show that the high temperature zone is longer and the local high-temperature could be avoided while the velocity difference decreases between the secondary air and the carbon particle, which leads to more uniformed temperature distribution and better induration quality. The work gives a right direction onimproving of pellet production.展开更多
In order to optimize the parameters of bowl-tray rice precision seeder and improve its performance,three major factors respectively at five levels,including shaped hole diameter,vertical displacement of rice seeds and...In order to optimize the parameters of bowl-tray rice precision seeder and improve its performance,three major factors respectively at five levels,including shaped hole diameter,vertical displacement of rice seeds and rotating speed of cam,were tested,the quadratic orthogonal rotational regression experiments were conducted,and the effects on seeding rate,leakage sowing rate and the injury rate were investigated.The test results show that factors affecting rice seeding rate are in the order of shaped hole diameter,rotating speed of cam and vertical displacement of rice seeds.The factors affecting rice planting leakage rate are in the order of shaped hole diameter,vertical displacement of rice seeds and rotating speed of cam,and the factors affecting rice injury rate are in the order of rotating speed of cam,vertical displacement of rice seeds and shaped hole diameter.Optimal parameters(shaped hole diameter:10 mm,vertical displacement of rice seeds:27 mm,rotating speed of cam:13 r/min)and performance index(seeding rate:95.43%,leakage sowing rate:0.37%,injury rate:0.58%)provided the basis for design and performance improvement of the bowl-tray rice precision seeder.展开更多
The mass loss rate of CaF2-CaO-Al2O3-SiO2-MgO slag system originated from ANF-6 was studied with CaF2, CaO, Al2O3, SiO2 or MgO content as variables. The method of quadratic regression orthogonal design was used for th...The mass loss rate of CaF2-CaO-Al2O3-SiO2-MgO slag system originated from ANF-6 was studied with CaF2, CaO, Al2O3, SiO2 or MgO content as variables. The method of quadratic regression orthogonal design was used for the design and analysis of the experiment. The experimental results indicated that mass loss rate of slag can be increased by 6% with CaF2 changing from 50%to 65%. Mass loss increases with SiO2 , Al2O3 and MgO adding and decreases with CaO content increasing. Because of the reaction between oxide and fluoride in the slag pool, apparent mass loss of CaF2-Al2O3 CaO-SiO2 MgO slag system appears at melting point. This will cause obvious composition change of electroslag. In addition, the segregation occurs in the slag skin forming process. This is another reason causing the composition change of electroslag.展开更多
According to the requirement of assorted maize transplanting machine,a maize bud-seed precise sowing device was presented for use in cold areas.Experiments were performed to optimise the parameters of a maize bowl-tra...According to the requirement of assorted maize transplanting machine,a maize bud-seed precise sowing device was presented for use in cold areas.Experiments were performed to optimise the parameters of a maize bowl-tray precise seeder to improve the seed-filling performance.When the diameter of brush seed wheel was 78 mm,the clearance of brushing seed was 3 mm,with the maize varieties Demeiya 1,the moisture content about 40%,the depth of shaped hole 6 mm,the two major factors,the diameter of shaped hole and the velocity of seed box,were tested at five levels for each factor using the orthogonal rotational regression experiment.The effects on the single-seed rate,multi-seed rate,empty-seed rate,broken-bud rate and damage rate were investigated.The test results indicated that the factors affecting the single-seed rate and the multi-seed rate were the diameters of shaped hole and the velocity of seeds box,and the factor affecting the empty-seed rate was primarily the diameter of shaped hole.This study determined the optimal parameters,and verified the results,which provide the basis for the design and performance improvement of the maize bud-seed bowl-tray precision seeder.展开更多
基金supported by Important National Science & Technology Specific Projects of China (No.2) (Nos.2009ZX02001,2011ZX02403)
文摘The geometry of an inductively coupled plasma (ICP) etcher is usually considered to be an important factor for determining both plasma and process uniformity over a large wafer. During the past few decades, these parameters were determined by the "trial and error" method, resulting in wastes of time and funds. In this paper, a new approach of regression orthogonal design with plasma simulation experiments is proposed to investigate the sensitivity of the structural parameters on the uniformity of plasma characteristics. The tool for simulating plasma is CFD-ACE+, which is commercial multi-physical modeling software that has been proven to be accurate for plasma simulation. The simulated experimental results are analyzed to get a regression equation on three structural parameters. Through this equation, engineers can compute the uniformity of the electron number density rapidly without modeling by CFD-ACE+. An optimization performed at the end produces good results.
文摘The thermal induced errors can account for as much as 70% of the dimensional errors on a workpiece. Accurate modeling of errors is an essential part of error compensation. Base on analyzing the existing approaches of the thermal error modeling for machine tools, a new approach of regression orthogonal design is proposed, which combines the statistic theory with machine structures, surrounding condition, engineering judgements, and experience in modeling. A whole computation and analysis procedure is given. Therefore, the model got from this method are more robust and practical than those got from the present method that depends on the modeling data completely. At last more than 100 applications of CNC turning center with only one thermal error model are given. The cutting diameter variation reduces from more than 35 μm to about 12 μm with the orthogonal regression modeling and compensation of thermal error.
文摘In this paper, the influence of plasma arc powder surfacing technical parameters on the property of layer is defined using the orthogonal design. By the orthogonal polynomial regression, when plasma arc powder surfacing is used on the surface of the X65 steel plate with the Fe-07 alloy powder, the optimum technical parameters are the following: I=180~190 A , G=41.5 g/min , v=102 mm/min , T_0=350 ℃ , Q_l=280 L/h , Q_s=400 L/h . Further, analysis of the cracking test data showed that the cracking preheat temperature is 350 ℃ .
基金Funded by the National Natural Science Foundation of China (No. 50635030)the Scientific and Technological Development Project of Jilin Province(No. 20090340)+2 种基金the Doctoral Program Foundation of Institutions of Higher Education of China(No.20100061110023)the Projects of Cooperation and Innovation to National Potential Oil and Gas for Production and Research,the Public Benefit Research Sector to Ministry and Resources(No. Sinoprobe09-01-07)the Graduate Innovation Fund of Jilin University(No.20091015)
文摘A three levels orthogonal table-L9(34) was used,namely,impact angle,rotating speed,erodent size,and surface configuration were considered.The three bionic surface configurations are pit,groove,and ring.The experimental results indicate the experiment factors affecting erosive rate are,in their sequence of contribution,erodent size,impact angle,configuration,and rotating speed;the erosive rate increased with increase in rotating speed,erodent size;the erosion resistance of the sample with ring structure is higher than that of the other two samples.Based on this result,regression orthogonal experiment was carried out to select the optimal erosion resistance condition with respect to the ring bionic surface configuration.Regression equations between erosive rate and experimental factors of ring surface configurations were obtained.
基金This work was supported by the National Natural Science Foundation of China(No.81773884,81473413,81274060)the National Science and Technology Major Project(No.2017ZX09301077)+1 种基金Guangzhou Science and Technology Project(No.201803010115)Technology Funds were obtained from the Key Unit of Chinese Medicine Digitalization Quality Evaluation of State Administration of Traditional Chinese Medicine.
文摘Background:Blood stasis syndrome is one of the major syndromes in the development of chronic conditions in traditional Chinese medicine.Blood stasis syndrome is closely related to microcirculation dysfunction and thrombosis.Trigonaceae,as a representative traditional Chinese medicine for promoting blood circulation and removing blood stasis,there are many studies on its anticoagulant,antiplatelet aggregation and antithrombotic effects.Methods:Optimization of sparganin compounds,comprising sparganin A,sparganin B,and sparganin C for the characterization of drug pair effects against blood stasis syndrome was carried out.Ternary quadratic regression orthogonal combination design was carried out in a mouse model of blood stasis syndrome.The concentrations of thromboxane B2,plasminogen activator inhibitor 1,fibrinogen,and endothelin 1 were evaluated by enzyme linked immunosorbent assay.Thymus,hepatic,and spleen indices were also assessed.The outcomes of the evaluations aided in identifying optimum parameter values for the most favorable precipitation against blood stasis syndrome.Subsequently,Cytoscape 3.7.1 was used for network pharmacology to predict the key targets of sparganins and disease.Results:After sparganin A,sparganin B,and sparganin C treatment,hepatic had a downward trend,while spleen indices and thymus had an upward trend.Compared with the model group,thromboxane B2,endothelin 1,plasminogen activator inhibitor 1,and fibrinogen were decreased(P<0.05).The blood stasis syndrome model regression equation was extremely significant,and the correlation coefficient of R was 0.939,indicating that sparganin A,sparganin B and sparganin C were positively correlated at all levels.According to the dosage of these three factors and test results,the equation was fitted and the maximum values of the three sparganin in the corresponding dose range were obtained as follows:A=0.2982 mg/10g,B=0.1438 mg/10g,C=0.0417 mg/10g.Thus,the optimum parameters were found to be 0.298:0.144:0.042 for synergistic drug combinations of sparganin compounds sparganin A,sparganin B,and sparganin C in blood stasis syndrome.The possible key targets of sparganins included matrix metalloproteinase 9,plasminogen,proto-oncogene tyrosine-protein kinase src,and akt serine/threonine kinase 1 in blood stasis syndrome.Conclusion:Our study for the first time found two novel cyclic peptide compounds sparganin B and sparganin C have an anti-blood stasis effect,and speculated sparganins key targets included matrix metalloproteinase 9,plasminogen,proto-oncogene tyrosine-protein kinase src,and akt serine/threonine kinase 1 in blood stasis syndrome.
基金funded by the National Key Technology R&D Program (2006BAD04A10)the Major Scientific and Technological Innovation Projects of Hebei Province (07227146Z)the Earmarked Fund for Modern Agro-industry (Dairy Industry) Technology Research System (nycytx-10)
文摘[ Objective] To study the effects of combined application of different elements on alfalfa hay yield. [ Medthod] Potassium sulfate, ammonium chloride, superphosphate and magnesium oxide were applied to alfalfa field in the experiment, and quaternary quadratic regression orthogonal combination was used to examine the effects of the experiment factors on hay yield of alfalfa. [ Result] The order of targets based on the effects on hay yield is as follows: potassium sulfate 〉 ammonium chloride 〉 magnesium oxide 〉 superphosphate. Among them, the potassium sulfate had a significant impact on alfalfa hay yield. The interaction between potassium sulfate and magnesium oxide also had a significant impact on alfalfa hay yield. [ Conclusion] The optimal cultivation measures for alfalfa hay yield of more than 19 224.6 kg/hm^2 are as follows: potassium sulfate, 163.253 - 181.679 kg/hm^2 ; ammonium chloride, 155.877 - 174.258 kg/hm^2 ; superphosphate, 566.177 - 632.924 kg/hm^2 ; and magnesium oxide, 30.060 - 33.628 kg/hm^2.
文摘Effects of Mg^2+, NTPs and Taq DNA polymerase in pear SSR-PCR system were analyzed by quadratic regressive orthogonal rotational combinational design. Results showed: absolute IOD (Integrated OD of each band) value of target band reduced with concentration rising of Mg^2+ and Taq DNA polymerase, but heightened with concentration rising of dNTPs. The decay rate of absolute IOD value increased progressively with rising Mg^2+ concentration, decreased gradually with rising Taq DNA polymerase concentration; the rising speed would be slower than the dNTPs increase. Absolute IOD value would reduce with concentration rising of dNTPs at a low level of Mg^2+ concentration. Conversely it would rise with the increase of dNTPs while high Mg^2+ concentration. Absolute IOD value would generally rise with concentration rising of Taq DNA polymerase while low Mg^2+ concentration. On the contrary it would reduce with concentration rising of Taq DNA polymerase while high Mg^2+ concentration.
文摘It is found that many biological organisms exhibit superior adhesion characteristics in wet environments. It has been observed that the foot pads of tree frogs and katydids are consist of a number of closely arranged polygons, most of them are hexagonal. In this paper, the common structure of two kinds of biological foot pad was extracted to model the bionic surface structure of friction plates. The friction plate prototypes were also prepared. Through the multivariate orthogonal regression design, the optimum parameter combination of the friction performances of the prototypes of the bionic plates has been obtained. The hexagonal circumcircle size is 10 mm, the groove width is 1 mm, and the hexagonal diagonal angle is 90~. Then the maximum static friction coefficient, dynamic friction coefficient and wear amount of the optimal friction plate were tested and compared with the control group friction plates. The comparative analysis of the experiment findings demonstrated that the bionic structure with hexagonal ring grooves can significantly improve the friction performance of the friction plates.
基金the National High Technology Research and Development Program(863) of China (No.2007AA05Z215)
文摘In order to optimize the pellet induration process parameters of rotary kiln, a mathematical model is developed and solved by using commercial software FLUENT. Orthogonal regression has been performed by using the simulated results of the pellet induration in rotary kiln. The functional relations between pellet induration quality and process parameters are obtained. The main parameters that affect the thermal process are also discussed. The results show that the high temperature zone is longer and the local high-temperature could be avoided while the velocity difference decreases between the secondary air and the carbon particle, which leads to more uniformed temperature distribution and better induration quality. The work gives a right direction onimproving of pellet production.
基金This work was supported by Science and Technology Research Projects of Education of the Heilongjiang Province of China(12531439)Natural Science Foundation of Heilongjiang Province of China(E201331)Heilongjiang Province Agricultural Reclamation Administration Science and Technology Projects(HNk11A-09-11-02).
文摘In order to optimize the parameters of bowl-tray rice precision seeder and improve its performance,three major factors respectively at five levels,including shaped hole diameter,vertical displacement of rice seeds and rotating speed of cam,were tested,the quadratic orthogonal rotational regression experiments were conducted,and the effects on seeding rate,leakage sowing rate and the injury rate were investigated.The test results show that factors affecting rice seeding rate are in the order of shaped hole diameter,rotating speed of cam and vertical displacement of rice seeds.The factors affecting rice planting leakage rate are in the order of shaped hole diameter,vertical displacement of rice seeds and rotating speed of cam,and the factors affecting rice injury rate are in the order of rotating speed of cam,vertical displacement of rice seeds and shaped hole diameter.Optimal parameters(shaped hole diameter:10 mm,vertical displacement of rice seeds:27 mm,rotating speed of cam:13 r/min)and performance index(seeding rate:95.43%,leakage sowing rate:0.37%,injury rate:0.58%)provided the basis for design and performance improvement of the bowl-tray rice precision seeder.
基金Item Sponsored by National Natural Science Foundation of China(50644040)
文摘The mass loss rate of CaF2-CaO-Al2O3-SiO2-MgO slag system originated from ANF-6 was studied with CaF2, CaO, Al2O3, SiO2 or MgO content as variables. The method of quadratic regression orthogonal design was used for the design and analysis of the experiment. The experimental results indicated that mass loss rate of slag can be increased by 6% with CaF2 changing from 50%to 65%. Mass loss increases with SiO2 , Al2O3 and MgO adding and decreases with CaO content increasing. Because of the reaction between oxide and fluoride in the slag pool, apparent mass loss of CaF2-Al2O3 CaO-SiO2 MgO slag system appears at melting point. This will cause obvious composition change of electroslag. In addition, the segregation occurs in the slag skin forming process. This is another reason causing the composition change of electroslag.
基金funded by the Science and Technology Research Project of Education Department of Heilongjiang Province(12531458)Specialized Research Fund for the Doctoral Program of Higher Education jointly funded subject(20132305110003)Natural Science Foundation of Heilongjiang Province(E201331).
文摘According to the requirement of assorted maize transplanting machine,a maize bud-seed precise sowing device was presented for use in cold areas.Experiments were performed to optimise the parameters of a maize bowl-tray precise seeder to improve the seed-filling performance.When the diameter of brush seed wheel was 78 mm,the clearance of brushing seed was 3 mm,with the maize varieties Demeiya 1,the moisture content about 40%,the depth of shaped hole 6 mm,the two major factors,the diameter of shaped hole and the velocity of seed box,were tested at five levels for each factor using the orthogonal rotational regression experiment.The effects on the single-seed rate,multi-seed rate,empty-seed rate,broken-bud rate and damage rate were investigated.The test results indicated that the factors affecting the single-seed rate and the multi-seed rate were the diameters of shaped hole and the velocity of seeds box,and the factor affecting the empty-seed rate was primarily the diameter of shaped hole.This study determined the optimal parameters,and verified the results,which provide the basis for the design and performance improvement of the maize bud-seed bowl-tray precision seeder.