[Objective]This paper aims to study the heredity and parental correlation of the oil content of the beginning of the generation at highoil content soybean.[Methods]Seven high yield or high-oil content soybean are sele...[Objective]This paper aims to study the heredity and parental correlation of the oil content of the beginning of the generation at highoil content soybean.[Methods]Seven high yield or high-oil content soybean are selected and eight crosses are made according to the NCII design.[Results]The variation of oil content in F5 relates with the difference between parents.The more the differences between both parents have,the more variations of the oil content of F5 become.When the oil content of both parents are high,and the maturating time of them are very different,the probability of high-oil plant in F5 derived from these cross are high.The oil content of F5 generation has negative correlation with the different between both parents and has positive correlation with the oil content of male parent and significant positive correlation with the oil content of female parent and mid-parent.[Conclusions]This study result provide reference for the seedling of High-oil Content Soybean.展开更多
Technological parameters of asymmetric cast-rolling under multi-energy field were investigated on horizontal twin roll caster(d400 mm×500 mm), and their effects on structures and properties of 1050 strips were ...Technological parameters of asymmetric cast-rolling under multi-energy field were investigated on horizontal twin roll caster(d400 mm×500 mm), and their effects on structures and properties of 1050 strips were analyzed by comparing with traditional cast-rolling. Results show that when length of cast-rolling area is 70 mm, melt temperature of head box is 670 °C, cast rolling speed is 1.3 m/min, exciting current is 10 A, center frequency is(13±1) Hz, ultrasonic power is 200 W and ultrasonic frequency is(20±0.2) kHz, the 1050 strip with the best microstructure can be prepared successfully; its center segregated layer disappears; the average grain size is reduced by about 40%; the crystal grains are distributed evenly; micro segregation decreases obviously; the precipitated phases are distributed along the grain boundaries evenly; and the tensile strength, yield strength, elongation and micro-hardness of cast-rolled strip are improved by 22.6%, 23.66%, 38.75% and 9.90%, respectively.展开更多
The heredity of aluminum melt under the action of pulse electric field was investigated by means of the remelt experiment. A new hereditary criterion under this condition was proposed; in the meantime, the differentia...The heredity of aluminum melt under the action of pulse electric field was investigated by means of the remelt experiment. A new hereditary criterion under this condition was proposed; in the meantime, the differential transferability of genetic carrier in activated melt among filial generations was validated with the aid of DSC.展开更多
Using S-rough sets, this paper gives the concepts off-heredity knowledge and its heredity coefficient, and f-variation coefficient of knowledge; presents the theorem of f-attribute dependence of variation coefficient ...Using S-rough sets, this paper gives the concepts off-heredity knowledge and its heredity coefficient, and f-variation coefficient of knowledge; presents the theorem of f-attribute dependence of variation coefficient and the relation theorem of heredity-variation. The attribute dependence of f-variation coefficient and the relation of heredity-variation are important characteristics of S-rough sets. From such discussion, this paper puts forward the heredity mining off-knowledge and the algorithm of heredity mining, also gives its relative application.展开更多
Several risk factors,which include heredity,ultra-violet (UV) light and chronic inflammation,contribute to pterygium development.However,there is no report integrating these factors in the pathogenesis of pterygium.Th...Several risk factors,which include heredity,ultra-violet (UV) light and chronic inflammation,contribute to pterygium development.However,there is no report integrating these factors in the pathogenesis of pterygium.The aim of this review is to describe the connection between heredity,UV,and inflammation in pterygium development.Existing reports indicate that sunlight exposure is the main factor in pterygium occurrence by inducing growth factor production or chronic inflammation or DNA damage.Heredity may be a factor.Our studies on factors in pterygium occurrence and recurrence identify that heredity is crucial for pterygium to develop,and that sunlight is only a trigger,and that chronic inflammation promotes pterygium enlargement.We propose that genetic factors may interfere with the control of fibrovascular proliferation while UV light or(sunlight)most likely only triggers pterygium development by inducing growth factors which promote vibrant fibrovascular proliferation in predisposed individuals.It also just triggers inflammation and collagenolysis,which may be promoters of the enlargement of the fibrovascular mass.Pterygium probably occurs in the presence of exuberant collagen production and profuse neovascularisation.展开更多
Salt stress is one of the major abiotic stresses affecting soybean growth. Genetic improvement for salt tolerance is an effective way to protect soybean yield under salt stress conditions. Successful improvement of sa...Salt stress is one of the major abiotic stresses affecting soybean growth. Genetic improvement for salt tolerance is an effective way to protect soybean yield under salt stress conditions. Successful improvement of salt tolerance in soybean relies on identifying genetic variation that confers tolerance in soybean germplasm and subsequently incorporating these genetic resources into cultivars. In this review, we summarize the progress in genetic diversity and genetics of salt tolerance in soybean, which includes identifying genetic diversity for salt tolerant germplasm; mapping QTLs conferring salt tolerance; map-based cloning; and conducting genome-wide association study(GWAS) analysis in soybean. Future research avenues are also discussed, including high throughput phenotyping technology, the CRISPR/Cas9 Genome-Editing System, and genomic selection technology for molecular breeding of salt tolerance.展开更多
Heredity of high pure aluminum melts under different pulse electric field was investigated by means of repetitious remelt experiment. The results indicate that the genetic coefficient by measurement of grain size of c...Heredity of high pure aluminum melts under different pulse electric field was investigated by means of repetitious remelt experiment. The results indicate that the genetic coefficient by measurement of grain size of cast structure has a close relation with pulse voltage. Moreover, the hereditary law accords with the function of In = 1+ e^-an+β. The stability of genetic carrier (cluster) comprises in the competition between repetitious cooling and heating impulse and the effect of electric pulse modification.展开更多
Cu/Al clad strips are prepared using solid?liquid cast-rolling bonding(SLCRB)technique with a d160mm×150mm twin-roll experimental caster.The extent of interfacial reactions,composition of the reaction products,an...Cu/Al clad strips are prepared using solid?liquid cast-rolling bonding(SLCRB)technique with a d160mm×150mm twin-roll experimental caster.The extent of interfacial reactions,composition of the reaction products,and their micro-morphology evolution in the SLCRB process are investigated with scanning electron microscope(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD).In the casting pool,initial aluminized coating is first generated on the copper strip surface,with the diffusion layer mainly consisting ofα(Al)+CuAl2and growing at high temperatures,with the maximum thickness of10μm.After sequent rolling below the kiss point,the diffusion layer is broken by severe elongation,which leads to an additional crack bond process with a fresh interface of virgin base metal.The average thickness is reduced from10to5μm.The reaction products,CuAl2,CuAl,and Cu9Al4,are dispersed along the rolling direction.Peeling and bending test results indicate that the fracture occurs in the aluminum substrate,and the morphology is a dimple pattern.No crack or separation is found at the bonding interface after90°-180°bending.The presented method provides an economical way to fabricate Cu/Al clad strip directly.展开更多
The heredity of clusters in rapidly cooled(Zr_(50)Cu_(50))_(100-x)Al_x melts and its correlation with glass-forming ability(GFA)are studied via molecular dynamics simulations.Pair distribution function and the largest...The heredity of clusters in rapidly cooled(Zr_(50)Cu_(50))_(100-x)Al_x melts and its correlation with glass-forming ability(GFA)are studied via molecular dynamics simulations.Pair distribution function and the largest standard cluster(LSC)are adopted to characterize the local atomic structures in the(Zr_(50)Cu_(50))_(100-x)Al_(x)systems.The[12/555]icosahedra and their medium-range order(IMRO)play an important role in forming(Zr_(50)Cu_(50))_(100-x)Al_(x)metallic glasses(MGs).The fraction of[12/555],the number of IMRO,and the maximum size of IMRO in MGs increase significantly with increasing x.A tracking study further reveals that the configuration heredity of icosahedral clusters starts from supercooled liquids.No direct correlation exists between the GFA and the onset temperature of continuous or stated heredity.Instead,a larger hereditary supercooled degree of icosahedra matches with better GFA of Al-doped Zr_(50)Cu_(50)alloys.展开更多
Based on twin-roll casting, a cast-rolling force model was proposed to predict the rolling force in the bimetal solid-liquid cast-rolling bonding(SLCRB) process. The solid-liquid bonding zone was assumed to be below t...Based on twin-roll casting, a cast-rolling force model was proposed to predict the rolling force in the bimetal solid-liquid cast-rolling bonding(SLCRB) process. The solid-liquid bonding zone was assumed to be below the kiss point(KP). The deformation resistance of the liquid zone was ignored. Then, the calculation model was derived. A 2D thermal-flow coupled simulation was established to provide a basis for the parameters in the model, and then the rolling forces of the Cu/Al clad strip at different rolling speeds were calculated. Meanwhile, through measurement experiments, the accuracy of the model was verified. The influence of the rolling speed, the substrate strip thickness, and the material on the rolling force was obtained. The results indicate that the rolling force decreases with the increase of the rolling speed and increases with the increase of the thickness and thermal conductivity of the substrate strip. The rolling force is closely related to the KP height. Therefore, the formulation of reasonable process parameters to control the KP height is of great significance to the stability of cast-rolling forming.展开更多
The remarkable heredity of liquid aluminum modified by electric pulse (EP, EPM) has been uncovered. For better understanding from all aspects on the hereditary properties, the present research deals with the heredity ...The remarkable heredity of liquid aluminum modified by electric pulse (EP, EPM) has been uncovered. For better understanding from all aspects on the hereditary properties, the present research deals with the heredity destruction and the secondary EPM procedure. It is shown that the secondary EPM is capable of preventing the heredity reduction of EP-modified liquid aluminum, and that the final refining effect has a close relationship with technique parameters of the secondary EPM. Furthermore, at a certain superheated temperature depending on the initial EPM technique parameters, the heredity relationship of EP-modified liquid aluminum can be cut off during remelting. High temperature X-ray diffraction combining with the DSC tests also indicates that the EP-induced structure changes have almost disappeared at an elevated remelting temperature.展开更多
To explore the complex thermal-mechanical-chemical behavior in the solid-liquid cast-roll bonding(SLCRB) of Cu/Al cladding strip, numerical simulations were conducted from both macro and micro scales. In macro-scale, ...To explore the complex thermal-mechanical-chemical behavior in the solid-liquid cast-roll bonding(SLCRB) of Cu/Al cladding strip, numerical simulations were conducted from both macro and micro scales. In macro-scale, with birth and death element method, a thermo-mechanical coupled finite element model(FEM) was set up to explore the temperature and contact pressure distribution at the Cu/Al bonding interface in the SLCRB process. Taking these macro-scale simulation results as boundary conditions, we simulated the atom diffusion law of the bonding interface by molecular dynamics(MD) in micro-scale. The results indicate that the temperature in Cu/Al bonding interface deceases from 700 to 320 ℃ from the entrance to the exit of caster, and the peak of contact pressure reaches up to 140 MPa. The interfacial diffusion thickness depends on temperature and rolling reduction, higher temperature results in larger thickness, and the rolling reduction below kiss point leads to significant elongation deformation of cladding strip which yields more newborn interface with fresh metal and make the diffusion layer thinner. The surface roughness of Cu strip was found to be benefit to atoms diffusion in the Cu/Al bonding interface. Meanwhile, combined with the SEM-EDS observation on the microstructure and composition in the bonding interface of the experimental samples acquired from the castrolling bite, it is revealed that the rolling reduction and severe elongation deformation in the solid-solid contact zone below kiss point guarantee the satisfactory metallurgical bonding with thin and smooth diffusion layer. The bonding mechanisms of reactive diffusion, mechanical interlocking and crack bonding are proved to coexist in the SLCRB process.展开更多
Spotted leaf(spl)mutant is a type of leaf lesion mimic mutants in plants.We obtained some lesion mimic mutants from ethyl methane sulfonate(EMS)-mutagenized wheat(Triticum aestivum L.)cultivar Guomai 301(wild type,WT)...Spotted leaf(spl)mutant is a type of leaf lesion mimic mutants in plants.We obtained some lesion mimic mutants from ethyl methane sulfonate(EMS)-mutagenized wheat(Triticum aestivum L.)cultivar Guomai 301(wild type,WT),and one of them was named as white stripe leaf(wsl)mutant because of the white stripes on its leaves.Here we report the heredity and gene mapping of this novel wheat mutant wsl.There are many small scattered white stripes on the leaves of wsl throughout its whole growth period.As the plants grew,the white stripes became more severe and the necrotic area expanded.The mutant wsl grew only weakly before the jointing stage and gradually recovered after jointing.The length and width of the flag leaf,spike number per plant and thousand-grain weight of wsl were significantly lower than those of the WT.Genetic analysis indicated that the trait of white stripe leaf was controlled by a recessive gene locus,named as wsl,which was mapped on the short arm of chromosome 6 B by SSR marker assay.Four SSR markers in the F2 population of wsl×CS were linked to wsl in the order of Xgpw1079–Xwmc104–Xgwm508-wsl–Xgpw7651 at 7.1,5.2,8.7,and 4.4 c M,respectively and three SSR markers in the F2 population of wsl×Jimai 22 were linked to wsl in the order of Xgwm508–Xwmc494–Xgwm518-wsl at 3.5,1.6 and 8.2 c M,respectively.In comparison to the reference genome sequence of Chinese Spring(CS),wsl is located in a 91-Mb region from 88 Mb(Xgwm518)to 179 Mb(Xgpw7651)on chromosome 6 BS.Mutant wsl is a novel germplasm for studying the molecular mechanism of wheat leaf development.展开更多
Heredity of microstructure in AlTiC master alloy, grain refiners, was analyzed. It is found that, for morphologies and distributions of TiC particles, there are visible heredity which originates from raw materials or ...Heredity of microstructure in AlTiC master alloy, grain refiners, was analyzed. It is found that, for morphologies and distributions of TiC particles, there are visible heredity which originates from raw materials or processing methods of Al melt, and will ultimately be transferred to the solid state structure through the melt stage, and this phenomenon can cause hereditary influences on refinement: formation of chain like TiC morphology results in rapid refinement fading behavior; distribution of TiC along grain boundaries greatly reduces refinement efficiency. Controlling of structural heredity through proper selections of raw materials and processing parameters is of great importance in obtaining ideal microstructures and improving refinement behaviors of AlTiC master alloys.展开更多
Macroscopic texture and microscopic orientation in hot-rolled and annealed sheets of nonoriented electrical steel were studied by XRD and EBSD techniques. The microstructure of hot-rolled and annealed samples was stud...Macroscopic texture and microscopic orientation in hot-rolled and annealed sheets of nonoriented electrical steel were studied by XRD and EBSD techniques. The microstructure of hot-rolled and annealed samples was studied by OM. Experimental results indicate that a strong heredity is observed in texture evolution between hot-rolled texture and annealed texture. Typical elements have a large effect on the recrystallization microstructure and texture distribution. The texture distribution through thickness is highly affected by recrystallization in hot rolled sheets. The recrystallization is boosted by Si and Al. Goss grains originate from cracked initial 〈100〉 columnar grains. {110}〈112〉, {112}〈111〉 and {111}〈112〉 grains are related to Goss grains. In subsurface lay of hot rolled sheets, Al can strengthen Goss texture and weaken copper-type texture. {112}〈111〉 texture and {110}〈112〉 texture are strengthened by Si. In the central layers, {100}〈001〉 texture and {111}〈121〉 texture are weakened by Al. {100}〈011〉 texture is increased by Al. Si can increase the proportion of γ-fiber texture and decrease that of {100}〈011〉 texture. In annealed texture, {100}〈001〉 texture and Goss texture are decreased by Al and Si. γ-fiber texture is increased by Si and {111}〈121〉 texture is preferentially increased by Al. The recrystallized grain size is increased and iron loss of annealed sheets is reduced by Al and Si, which means that the magnetic properties are optimized by the Al and Si content.展开更多
Through the polyacrylamide gel clectrophoresis analysis of thirty-two needle samples of ninty-years old pinus koraiensis in Harbin, seven typies of zone and distribution of the zone frequency, and some objective fact ...Through the polyacrylamide gel clectrophoresis analysis of thirty-two needle samples of ninty-years old pinus koraiensis in Harbin, seven typies of zone and distribution of the zone frequency, and some objective fact of heredity and variation were determined. These informations can be used as reference materials in the research of heredity and variation of pinus koraiensis.展开更多
A new concept of undercooling heredity is developed to evaluate the undercooling ability in a non catalytic nucleation coated mould, where alloy melts were highly undercooled previously. Before the heredity experiment...A new concept of undercooling heredity is developed to evaluate the undercooling ability in a non catalytic nucleation coated mould, where alloy melts were highly undercooled previously. Before the heredity experiment a non catalytic nucleation composite glass lined coating (B F) was prepared on the inner surface of mould and the Cu 70 Ni 30 alloy was selected to perform undercooling experiment in the B F non catalytic coating mould. Its ratio of undercooling heredity was 0.76. The results prove that the B F coating is an ideal non catalytic media for purified Cu 70 Ni 30 alloy melts due to its small contact angle between the melt and coating layer. Considering that various microstructures form under different undercoolings, two critical undercoolings, Δ T 1 and Δ T 2, and their corresponding microstructures of Cu 70 Ni 30 alloy are well defined. Moreover, it is found that the manned trigging solidification in the non catalytic coating mould could be used to get directional undercooling dendrite structure while the melt undercooling is larger than the critical undercooling Δ T 2.展开更多
Bruchid is a serious insect pest of mungbean [Vigna radiata (L.) Wilczek] and can inflict serious loss. A resistant variety from India, V2709, was crossed with a susceptible variety, Zhonglti 1, from the World Veget...Bruchid is a serious insect pest of mungbean [Vigna radiata (L.) Wilczek] and can inflict serious loss. A resistant variety from India, V2709, was crossed with a susceptible variety, Zhonglti 1, from the World Vegetable Center, Asian Vegetable Research and Development Center (AVRDC). Segregation of the F2, BC1F1, and F3 populations showed that bruchid resistance of V2709 is controlled by a single dominant locus. To find molecular marker linked with the resistant locus, 63 randomly amplified polymorphic DNA markers and 113 sets of SSR/STS primers were used in a bulked segregant analysis. Two of the markers, OPC-06 and STSbr2, were found to be linked with the locus (named as Br2). Further analysis suggested that the genetic distances between these two markers and Br2 were 11.0 and 5.8 cM, respectively.展开更多
The chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) of 16 Populus species (Section Leuce) and their F1 generation were detected using PCR-RFLP technique. The results show that cpDNA in the F1 generation of...The chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) of 16 Populus species (Section Leuce) and their F1 generation were detected using PCR-RFLP technique. The results show that cpDNA in the F1 generation of 22 hybrid combinations was inherited maternally, which supported the conclusions of the study of plasmid cytology. The mtDNA fragments amplified by PCR were consistent with the restriction maps in all hybrid combinations and no polymorphism was detected, indicating that the Section Leuce is highly conserved in mitochondrial gene sequences. These results provided direct evidence of maternal chloroplast inheritance in Populus tomentosa, P. bolleana, P. davidiana, P. adenopoda, P. tomentosa × P. bolleana, P. alba × P. glandulosa and P. alba × P. tomentosa.展开更多
Hereditary is one of the key risk factors of the Parkinson’s disease (PD) and children of individuals with the Parkinson’s carry a two-fold risk for the disease. In this article, chance of developing the Parkinson’...Hereditary is one of the key risk factors of the Parkinson’s disease (PD) and children of individuals with the Parkinson’s carry a two-fold risk for the disease. In this article, chance of developing the Parkinson’s disease is estimated for an individual in five types of families. That is, families with negative history of the PD (I), families with positive history where neither one of the parents (II), one of the parents (III-IV), or both parents (V) are diagnosed with the disease. After a sophisticated modeling, Maximum Likelihood and Bayesian Approach are used to estimate the chance of developing the Parkinson’s in the five mentioned family types. It is extremely important knowing such probabilities as the individual can take precautionary measures to defy the odds. While many physicians have provided medical opinions on chance of developing the PD, our study is one of the first to provide statistical modeling and analysis with real data to support the conclusions.展开更多
文摘[Objective]This paper aims to study the heredity and parental correlation of the oil content of the beginning of the generation at highoil content soybean.[Methods]Seven high yield or high-oil content soybean are selected and eight crosses are made according to the NCII design.[Results]The variation of oil content in F5 relates with the difference between parents.The more the differences between both parents have,the more variations of the oil content of F5 become.When the oil content of both parents are high,and the maturating time of them are very different,the probability of high-oil plant in F5 derived from these cross are high.The oil content of F5 generation has negative correlation with the different between both parents and has positive correlation with the oil content of male parent and significant positive correlation with the oil content of female parent and mid-parent.[Conclusions]This study result provide reference for the seedling of High-oil Content Soybean.
基金Project(2014CB046702)supported by National Basic Research Program of China
文摘Technological parameters of asymmetric cast-rolling under multi-energy field were investigated on horizontal twin roll caster(d400 mm×500 mm), and their effects on structures and properties of 1050 strips were analyzed by comparing with traditional cast-rolling. Results show that when length of cast-rolling area is 70 mm, melt temperature of head box is 670 °C, cast rolling speed is 1.3 m/min, exciting current is 10 A, center frequency is(13±1) Hz, ultrasonic power is 200 W and ultrasonic frequency is(20±0.2) kHz, the 1050 strip with the best microstructure can be prepared successfully; its center segregated layer disappears; the average grain size is reduced by about 40%; the crystal grains are distributed evenly; micro segregation decreases obviously; the precipitated phases are distributed along the grain boundaries evenly; and the tensile strength, yield strength, elongation and micro-hardness of cast-rolled strip are improved by 22.6%, 23.66%, 38.75% and 9.90%, respectively.
基金Item Sponsored by National Natural Science Foundation of China(50174028and50674054)
文摘The heredity of aluminum melt under the action of pulse electric field was investigated by means of the remelt experiment. A new hereditary criterion under this condition was proposed; in the meantime, the differential transferability of genetic carrier in activated melt among filial generations was validated with the aid of DSC.
基金This project was supported by the National Natural Science Foundation of China (60364001), the Shandong ProvincialNatural Science Foundation of China (Y2004A04) and Fujian Provincial Education Foundation of China(JA04268).
文摘Using S-rough sets, this paper gives the concepts off-heredity knowledge and its heredity coefficient, and f-variation coefficient of knowledge; presents the theorem of f-attribute dependence of variation coefficient and the relation theorem of heredity-variation. The attribute dependence of f-variation coefficient and the relation of heredity-variation are important characteristics of S-rough sets. From such discussion, this paper puts forward the heredity mining off-knowledge and the algorithm of heredity mining, also gives its relative application.
文摘Several risk factors,which include heredity,ultra-violet (UV) light and chronic inflammation,contribute to pterygium development.However,there is no report integrating these factors in the pathogenesis of pterygium.The aim of this review is to describe the connection between heredity,UV,and inflammation in pterygium development.Existing reports indicate that sunlight exposure is the main factor in pterygium occurrence by inducing growth factor production or chronic inflammation or DNA damage.Heredity may be a factor.Our studies on factors in pterygium occurrence and recurrence identify that heredity is crucial for pterygium to develop,and that sunlight is only a trigger,and that chronic inflammation promotes pterygium enlargement.We propose that genetic factors may interfere with the control of fibrovascular proliferation while UV light or(sunlight)most likely only triggers pterygium development by inducing growth factors which promote vibrant fibrovascular proliferation in predisposed individuals.It also just triggers inflammation and collagenolysis,which may be promoters of the enlargement of the fibrovascular mass.Pterygium probably occurs in the presence of exuberant collagen production and profuse neovascularisation.
基金supported by the National Natural Science Foundation of China (31401407)
文摘Salt stress is one of the major abiotic stresses affecting soybean growth. Genetic improvement for salt tolerance is an effective way to protect soybean yield under salt stress conditions. Successful improvement of salt tolerance in soybean relies on identifying genetic variation that confers tolerance in soybean germplasm and subsequently incorporating these genetic resources into cultivars. In this review, we summarize the progress in genetic diversity and genetics of salt tolerance in soybean, which includes identifying genetic diversity for salt tolerant germplasm; mapping QTLs conferring salt tolerance; map-based cloning; and conducting genome-wide association study(GWAS) analysis in soybean. Future research avenues are also discussed, including high throughput phenotyping technology, the CRISPR/Cas9 Genome-Editing System, and genomic selection technology for molecular breeding of salt tolerance.
基金Item Sponsored by National Natural Science Foundation of China (50174028 ,50674054)
文摘Heredity of high pure aluminum melts under different pulse electric field was investigated by means of repetitious remelt experiment. The results indicate that the genetic coefficient by measurement of grain size of cast structure has a close relation with pulse voltage. Moreover, the hereditary law accords with the function of In = 1+ e^-an+β. The stability of genetic carrier (cluster) comprises in the competition between repetitious cooling and heating impulse and the effect of electric pulse modification.
基金Project(51474189)supported by the National Natural Science Foundation of ChinaProject(QN2015214)supported by the Educational Commission of Hebei Province,China
文摘Cu/Al clad strips are prepared using solid?liquid cast-rolling bonding(SLCRB)technique with a d160mm×150mm twin-roll experimental caster.The extent of interfacial reactions,composition of the reaction products,and their micro-morphology evolution in the SLCRB process are investigated with scanning electron microscope(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD).In the casting pool,initial aluminized coating is first generated on the copper strip surface,with the diffusion layer mainly consisting ofα(Al)+CuAl2and growing at high temperatures,with the maximum thickness of10μm.After sequent rolling below the kiss point,the diffusion layer is broken by severe elongation,which leads to an additional crack bond process with a fresh interface of virgin base metal.The average thickness is reduced from10to5μm.The reaction products,CuAl2,CuAl,and Cu9Al4,are dispersed along the rolling direction.Peeling and bending test results indicate that the fracture occurs in the aluminum substrate,and the morphology is a dimple pattern.No crack or separation is found at the bonding interface after90°-180°bending.The presented method provides an economical way to fabricate Cu/Al clad strip directly.
基金the National Natural Science Foundation of China(Grant No.51701071)the Natural Science Foundation of Hunan Province,China(Grant Nos.2018JJ3100 and 2018JJ2078)the Project of the Hunan Educational Department,China(Grant No.19B122)。
文摘The heredity of clusters in rapidly cooled(Zr_(50)Cu_(50))_(100-x)Al_x melts and its correlation with glass-forming ability(GFA)are studied via molecular dynamics simulations.Pair distribution function and the largest standard cluster(LSC)are adopted to characterize the local atomic structures in the(Zr_(50)Cu_(50))_(100-x)Al_(x)systems.The[12/555]icosahedra and their medium-range order(IMRO)play an important role in forming(Zr_(50)Cu_(50))_(100-x)Al_(x)metallic glasses(MGs).The fraction of[12/555],the number of IMRO,and the maximum size of IMRO in MGs increase significantly with increasing x.A tracking study further reveals that the configuration heredity of icosahedral clusters starts from supercooled liquids.No direct correlation exists between the GFA and the onset temperature of continuous or stated heredity.Instead,a larger hereditary supercooled degree of icosahedra matches with better GFA of Al-doped Zr_(50)Cu_(50)alloys.
基金The authors are grateful for the financial supports from the National Natural Science Foundation of China(51974278)the Distinguished Young Fund of Natural Science Foundation of Hebei Province,China(E2018203446).
文摘Based on twin-roll casting, a cast-rolling force model was proposed to predict the rolling force in the bimetal solid-liquid cast-rolling bonding(SLCRB) process. The solid-liquid bonding zone was assumed to be below the kiss point(KP). The deformation resistance of the liquid zone was ignored. Then, the calculation model was derived. A 2D thermal-flow coupled simulation was established to provide a basis for the parameters in the model, and then the rolling forces of the Cu/Al clad strip at different rolling speeds were calculated. Meanwhile, through measurement experiments, the accuracy of the model was verified. The influence of the rolling speed, the substrate strip thickness, and the material on the rolling force was obtained. The results indicate that the rolling force decreases with the increase of the rolling speed and increases with the increase of the thickness and thermal conductivity of the substrate strip. The rolling force is closely related to the KP height. Therefore, the formulation of reasonable process parameters to control the KP height is of great significance to the stability of cast-rolling forming.
基金supported financially by the National Natural Science Foundation of China(No.51074087)the Liaoning BaiQianWan Talents Program(No.2010921096)
文摘The remarkable heredity of liquid aluminum modified by electric pulse (EP, EPM) has been uncovered. For better understanding from all aspects on the hereditary properties, the present research deals with the heredity destruction and the secondary EPM procedure. It is shown that the secondary EPM is capable of preventing the heredity reduction of EP-modified liquid aluminum, and that the final refining effect has a close relationship with technique parameters of the secondary EPM. Furthermore, at a certain superheated temperature depending on the initial EPM technique parameters, the heredity relationship of EP-modified liquid aluminum can be cut off during remelting. High temperature X-ray diffraction combining with the DSC tests also indicates that the EP-induced structure changes have almost disappeared at an elevated remelting temperature.
基金Funded by the General Program of National Natural Science Foundation of China(Nos.51474189 and 51674222)the Excellent Youth Foundation of Hebei Scientific Committee,China(No.E2018203446)the Scientific Research Foundation of the Higher Education Institutions of Hebei Province,China(No.QN2015214)
文摘To explore the complex thermal-mechanical-chemical behavior in the solid-liquid cast-roll bonding(SLCRB) of Cu/Al cladding strip, numerical simulations were conducted from both macro and micro scales. In macro-scale, with birth and death element method, a thermo-mechanical coupled finite element model(FEM) was set up to explore the temperature and contact pressure distribution at the Cu/Al bonding interface in the SLCRB process. Taking these macro-scale simulation results as boundary conditions, we simulated the atom diffusion law of the bonding interface by molecular dynamics(MD) in micro-scale. The results indicate that the temperature in Cu/Al bonding interface deceases from 700 to 320 ℃ from the entrance to the exit of caster, and the peak of contact pressure reaches up to 140 MPa. The interfacial diffusion thickness depends on temperature and rolling reduction, higher temperature results in larger thickness, and the rolling reduction below kiss point leads to significant elongation deformation of cladding strip which yields more newborn interface with fresh metal and make the diffusion layer thinner. The surface roughness of Cu strip was found to be benefit to atoms diffusion in the Cu/Al bonding interface. Meanwhile, combined with the SEM-EDS observation on the microstructure and composition in the bonding interface of the experimental samples acquired from the castrolling bite, it is revealed that the rolling reduction and severe elongation deformation in the solid-solid contact zone below kiss point guarantee the satisfactory metallurgical bonding with thin and smooth diffusion layer. The bonding mechanisms of reactive diffusion, mechanical interlocking and crack bonding are proved to coexist in the SLCRB process.
基金supported by the National Natural Science Foundation of China(NSFC,31571646)the Science and Technology Project in Henan Province,China(182102110147)。
文摘Spotted leaf(spl)mutant is a type of leaf lesion mimic mutants in plants.We obtained some lesion mimic mutants from ethyl methane sulfonate(EMS)-mutagenized wheat(Triticum aestivum L.)cultivar Guomai 301(wild type,WT),and one of them was named as white stripe leaf(wsl)mutant because of the white stripes on its leaves.Here we report the heredity and gene mapping of this novel wheat mutant wsl.There are many small scattered white stripes on the leaves of wsl throughout its whole growth period.As the plants grew,the white stripes became more severe and the necrotic area expanded.The mutant wsl grew only weakly before the jointing stage and gradually recovered after jointing.The length and width of the flag leaf,spike number per plant and thousand-grain weight of wsl were significantly lower than those of the WT.Genetic analysis indicated that the trait of white stripe leaf was controlled by a recessive gene locus,named as wsl,which was mapped on the short arm of chromosome 6 B by SSR marker assay.Four SSR markers in the F2 population of wsl×CS were linked to wsl in the order of Xgpw1079–Xwmc104–Xgwm508-wsl–Xgpw7651 at 7.1,5.2,8.7,and 4.4 c M,respectively and three SSR markers in the F2 population of wsl×Jimai 22 were linked to wsl in the order of Xgwm508–Xwmc494–Xgwm518-wsl at 3.5,1.6 and 8.2 c M,respectively.In comparison to the reference genome sequence of Chinese Spring(CS),wsl is located in a 91-Mb region from 88 Mb(Xgwm518)to 179 Mb(Xgpw7651)on chromosome 6 BS.Mutant wsl is a novel germplasm for studying the molecular mechanism of wheat leaf development.
文摘Heredity of microstructure in AlTiC master alloy, grain refiners, was analyzed. It is found that, for morphologies and distributions of TiC particles, there are visible heredity which originates from raw materials or processing methods of Al melt, and will ultimately be transferred to the solid state structure through the melt stage, and this phenomenon can cause hereditary influences on refinement: formation of chain like TiC morphology results in rapid refinement fading behavior; distribution of TiC along grain boundaries greatly reduces refinement efficiency. Controlling of structural heredity through proper selections of raw materials and processing parameters is of great importance in obtaining ideal microstructures and improving refinement behaviors of AlTiC master alloys.
基金Funded by the Fundamental Research Funds for the Central Universities(TP-A3)(No.:FRF-TP-15-063A3)
文摘Macroscopic texture and microscopic orientation in hot-rolled and annealed sheets of nonoriented electrical steel were studied by XRD and EBSD techniques. The microstructure of hot-rolled and annealed samples was studied by OM. Experimental results indicate that a strong heredity is observed in texture evolution between hot-rolled texture and annealed texture. Typical elements have a large effect on the recrystallization microstructure and texture distribution. The texture distribution through thickness is highly affected by recrystallization in hot rolled sheets. The recrystallization is boosted by Si and Al. Goss grains originate from cracked initial 〈100〉 columnar grains. {110}〈112〉, {112}〈111〉 and {111}〈112〉 grains are related to Goss grains. In subsurface lay of hot rolled sheets, Al can strengthen Goss texture and weaken copper-type texture. {112}〈111〉 texture and {110}〈112〉 texture are strengthened by Si. In the central layers, {100}〈001〉 texture and {111}〈121〉 texture are weakened by Al. {100}〈011〉 texture is increased by Al. Si can increase the proportion of γ-fiber texture and decrease that of {100}〈011〉 texture. In annealed texture, {100}〈001〉 texture and Goss texture are decreased by Al and Si. γ-fiber texture is increased by Si and {111}〈121〉 texture is preferentially increased by Al. The recrystallized grain size is increased and iron loss of annealed sheets is reduced by Al and Si, which means that the magnetic properties are optimized by the Al and Si content.
文摘Through the polyacrylamide gel clectrophoresis analysis of thirty-two needle samples of ninty-years old pinus koraiensis in Harbin, seven typies of zone and distribution of the zone frequency, and some objective fact of heredity and variation were determined. These informations can be used as reference materials in the research of heredity and variation of pinus koraiensis.
文摘A new concept of undercooling heredity is developed to evaluate the undercooling ability in a non catalytic nucleation coated mould, where alloy melts were highly undercooled previously. Before the heredity experiment a non catalytic nucleation composite glass lined coating (B F) was prepared on the inner surface of mould and the Cu 70 Ni 30 alloy was selected to perform undercooling experiment in the B F non catalytic coating mould. Its ratio of undercooling heredity was 0.76. The results prove that the B F coating is an ideal non catalytic media for purified Cu 70 Ni 30 alloy melts due to its small contact angle between the melt and coating layer. Considering that various microstructures form under different undercoolings, two critical undercoolings, Δ T 1 and Δ T 2, and their corresponding microstructures of Cu 70 Ni 30 alloy are well defined. Moreover, it is found that the manned trigging solidification in the non catalytic coating mould could be used to get directional undercooling dendrite structure while the melt undercooling is larger than the critical undercooling Δ T 2.
基金supported by the National Natural Science Foundation of China(30170635)Crop Germplasm Protection,China(NB04-22-12)National Facilities and Information Infrastructure for Scinece and Technology,China(2004DKA30380-08,National Key Technology Support Plan,China(2006BAD02B08),Science and Technology of Agricultural Vocation,China(nyhyzx07-017).
文摘Bruchid is a serious insect pest of mungbean [Vigna radiata (L.) Wilczek] and can inflict serious loss. A resistant variety from India, V2709, was crossed with a susceptible variety, Zhonglti 1, from the World Vegetable Center, Asian Vegetable Research and Development Center (AVRDC). Segregation of the F2, BC1F1, and F3 populations showed that bruchid resistance of V2709 is controlled by a single dominant locus. To find molecular marker linked with the resistant locus, 63 randomly amplified polymorphic DNA markers and 113 sets of SSR/STS primers were used in a bulked segregant analysis. Two of the markers, OPC-06 and STSbr2, were found to be linked with the locus (named as Br2). Further analysis suggested that the genetic distances between these two markers and Br2 were 11.0 and 5.8 cM, respectively.
基金the National Science Foundation of China (Grant Nos. 30771747 and 30640036)the Beijing Natural Science Foundation (No. 6042020)+1 种基金the research projects supported by the Hebei Education Department (No. Z2010102)the Baoding University (No. 2010Z02)
文摘The chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) of 16 Populus species (Section Leuce) and their F1 generation were detected using PCR-RFLP technique. The results show that cpDNA in the F1 generation of 22 hybrid combinations was inherited maternally, which supported the conclusions of the study of plasmid cytology. The mtDNA fragments amplified by PCR were consistent with the restriction maps in all hybrid combinations and no polymorphism was detected, indicating that the Section Leuce is highly conserved in mitochondrial gene sequences. These results provided direct evidence of maternal chloroplast inheritance in Populus tomentosa, P. bolleana, P. davidiana, P. adenopoda, P. tomentosa × P. bolleana, P. alba × P. glandulosa and P. alba × P. tomentosa.
文摘Hereditary is one of the key risk factors of the Parkinson’s disease (PD) and children of individuals with the Parkinson’s carry a two-fold risk for the disease. In this article, chance of developing the Parkinson’s disease is estimated for an individual in five types of families. That is, families with negative history of the PD (I), families with positive history where neither one of the parents (II), one of the parents (III-IV), or both parents (V) are diagnosed with the disease. After a sophisticated modeling, Maximum Likelihood and Bayesian Approach are used to estimate the chance of developing the Parkinson’s in the five mentioned family types. It is extremely important knowing such probabilities as the individual can take precautionary measures to defy the odds. While many physicians have provided medical opinions on chance of developing the PD, our study is one of the first to provide statistical modeling and analysis with real data to support the conclusions.