This paper presents a method of measuring local slip in bamboo-reinforced concrete beams.Local slips(so)are calculated by reducing the elongation of the bamboo reinforcement(ebo)with the elongation of the concrete(eco...This paper presents a method of measuring local slip in bamboo-reinforced concrete beams.Local slips(so)are calculated by reducing the elongation of the bamboo reinforcement(ebo)with the elongation of the concrete(eco).The elongation of bamboo reinforcement(ebo)is determined in two ways,namely,read directly through a straingauge mounted on the bamboo reinforcement and calculated based on the force analysis or curvature moment as a control.The elongation of the concrete(eco)is calculated using force analysis or curvature moment.The process of calculating curvature moments and bond stress employs the Excel program.The steps in calculating the elongation of concrete(eco)consist of calculating the curvature moment,calculating the bond-stress at the initial crack,and calculating the bond-stress at the second crack until the beam collapses.Further,the results of the calculation of the elongation of the concrete(eco)and the elongation of the bamboo reinforcement(ebo)resulting from the reading of the strain-gauge are substituted in the local slip calculation equation.The results of the calculation analysis show that the local slip is approaching the local slip resulting from the experiment.The relationship behavior of bond-stress vs.slip indicates conformity with the experimental results.The local slip calculation based on the moment-curvature can be considered as control of the experiment result.展开更多
An experiment is made to detect the land-cover change in the area located to the south of Aksu in the northern Taklimakan desert through analyses of satellite data pixel by pixel basis. The analyzed data are those obs...An experiment is made to detect the land-cover change in the area located to the south of Aksu in the northern Taklimakan desert through analyses of satellite data pixel by pixel basis. The analyzed data are those observed in the late summer and early autumn of 1973, 1977, 1993 and 1995. As a parameter of land-cover, SAVI (Soil Adjusted Vegetation Index) derived from the data of Landsat MSS and JERS-1 OPS (Optical Sensor) is used. The result indicates the increase of vegetation in the oasis areas, confluent area of the Yarkant and Kashgar Rivers and around reservoirs while little change occurs in the desert area. The 1973 satellite image shows the abundant flow in the Yarkant River while the river is almost dried up in the satellite images of later years. The trend of the decrease in the Hotan River flow is recognized although not so dramatic as that of the Yarkant River.展开更多
[Objectives]This study was conducted to screen out reasonable pruning methods of walnut,and provide practical guidance for high-yield cultivation of walnut.[Methods]Xinfeng and Xinguang were used to study the effects ...[Objectives]This study was conducted to screen out reasonable pruning methods of walnut,and provide practical guidance for high-yield cultivation of walnut.[Methods]Xinfeng and Xinguang were used to study the effects of mechanical and artificial pruning methods on shoot growth,chlorophyll content in leaves,net photosynthetic rate and fruit quality.[Results]The results showed that:①the pruning method had a significant impact on the number of new shoots,and the number of new shoots of mechanical pruning was significantly higher than that of manual pruning;②the pruning method had a significant impact on the chlorophyll content,and the chlorophyll content of Xinguang of mechanical pruning was significantly higher than that of manual pruning;③the pruning method had a significant impact on the net photosynthetic rate of leaves,and the net photosynthetic rate of manual pruning was significantly higher than that of manual pruning;④Pruning methods had a significant effect on the number of walnut fruit,and the fruit trees pruned manually were significantly higher than those pruned mechanically;⑤the pruning method had no significant impact on the single fruit weight;⑥Pruning methods had a significant effect on the shell yield of a single walnut plant.The shell yield of single walnut plant pruned manually was significantly higher than that pruned mechanically;⑦pruning mode had a significant impact on the yield of walnut per plant,and the yield of artificially pruned walnut per plant was significantly higher than that of mechanical pruning;and⑧Xinfeng s chlorophyll content,net photosynthetic rate,fruit number,shell yield per plant and kernel yield per plant were all better than that of Xinguang,in addition,the growth and development of new shoots,the fruit quantity and quality of fruit also were affected by the interaction effect of genotype and pruning mode×variety.[Conclusions]It can be seen that different pruning methods have significant effects on the growth and development of new shoots and fruit yield a展开更多
This paper reviews the recent progress in the understanding of the dynamics of Pb(B_(1/2)B0_(1/2))O_(3)-type relaxor ferroelectrics using of broadband micro-Brillouin scattering spectroscopy,which covers a large frequ...This paper reviews the recent progress in the understanding of the dynamics of Pb(B_(1/2)B0_(1/2))O_(3)-type relaxor ferroelectrics using of broadband micro-Brillouin scattering spectroscopy,which covers a large frequency range from 1 to 1000 GHz by a tandem multi-pass FabryPerot interferometer.In contrast to Pb(B_(1/3)B0_(2/3))O_(3)-type relaxors,there is no frustration on the B-site of perovskite structure and the degree of order of B-site cations depends on heat treatment.Remarkable softening of sound velocity and an intense central peak are observed above the Curie temperature TC owing to the polarization°uctuations in polar nanoregions(PNRs).Unlike the Pb(B_(1/3)B0_(2/3))O_(3)relaxors,Pb(B_(1/2)B'_(1/2))O_(3)does not undergoes a typical diffuse phase transition without lead vacancies on A-site which enhances randomfields.For the(1-x)Pb(B_(1/2)B'_(1/2))O_(3-x)PbTiO_(3)solid solutions,the long range polar order increases as the PbTiO_(3)content increases.Nevertheless,a central peak owing to dynamic PNRs still remains even for the composition near the MPB,and a critical slowing down is clearly observed in the vicinity of TC.展开更多
In this paper,we investigate a deteriorating system with single vacation of a repairman.The system is described by infinite differential-integral equations with boundary conditions.Firstly,by using functional analysis...In this paper,we investigate a deteriorating system with single vacation of a repairman.The system is described by infinite differential-integral equations with boundary conditions.Firstly,by using functional analysis methods,especially linear operator’s C;-semigroup theory,we prove the well-posedness of the system and the existence of a unique positive dynamic solution that satisfies probability condition.Next,by analyzing the spectral properties of the system operator,we prove that all points on the imaginary axis except zero belong to the resolvent set of the system operator.Lastly,we prove that zero is not an eigenvalue of the system operator,which implies that the steady-state solution of the system does not exist.展开更多
Room-temperature Raman scattering and x-ray difraction measurements together with first principles calculations were employed to invetigate the behavior of disordered Pb(In_(1/2)Nb_(1/2))O_(3)(PIN)under pressure up to...Room-temperature Raman scattering and x-ray difraction measurements together with first principles calculations were employed to invetigate the behavior of disordered Pb(In_(1/2)Nb_(1/2))O_(3)(PIN)under pressure up to 50GPa.Raman spectra show broad bands but a peak near the 380cm^(-1) increases its intensity with pressure.The linewidth of the band at 550cm^(-1) also increases with pressure,while two of the Raman peaks merge above 6GPa.Above 16 GPa,we observe additional splitting of the band at 50cm^(-1).The pressure evolution of the diffraction patterns for PIN shows obvious Bragg peaks splitting above 16GPa;consistent with a symmetry lowering transition.The transition at 0.5 GPa is identified as a pseudo-cubic to orthorhombic(Pbam)structural change whereas the transition at 16GPa is istructure and associated with changes in linear compresibility and octahedral titling,and the transition at 30 GPa is associated to an orthorhombic to monoclinic change.First-principles calculations indicate that the Pbam structure is ground state with antiferrodisdortion consistent with experiment.展开更多
文摘This paper presents a method of measuring local slip in bamboo-reinforced concrete beams.Local slips(so)are calculated by reducing the elongation of the bamboo reinforcement(ebo)with the elongation of the concrete(eco).The elongation of bamboo reinforcement(ebo)is determined in two ways,namely,read directly through a straingauge mounted on the bamboo reinforcement and calculated based on the force analysis or curvature moment as a control.The elongation of the concrete(eco)is calculated using force analysis or curvature moment.The process of calculating curvature moments and bond stress employs the Excel program.The steps in calculating the elongation of concrete(eco)consist of calculating the curvature moment,calculating the bond-stress at the initial crack,and calculating the bond-stress at the second crack until the beam collapses.Further,the results of the calculation of the elongation of the concrete(eco)and the elongation of the bamboo reinforcement(ebo)resulting from the reading of the strain-gauge are substituted in the local slip calculation equation.The results of the calculation analysis show that the local slip is approaching the local slip resulting from the experiment.The relationship behavior of bond-stress vs.slip indicates conformity with the experimental results.The local slip calculation based on the moment-curvature can be considered as control of the experiment result.
文摘An experiment is made to detect the land-cover change in the area located to the south of Aksu in the northern Taklimakan desert through analyses of satellite data pixel by pixel basis. The analyzed data are those observed in the late summer and early autumn of 1973, 1977, 1993 and 1995. As a parameter of land-cover, SAVI (Soil Adjusted Vegetation Index) derived from the data of Landsat MSS and JERS-1 OPS (Optical Sensor) is used. The result indicates the increase of vegetation in the oasis areas, confluent area of the Yarkant and Kashgar Rivers and around reservoirs while little change occurs in the desert area. The 1973 satellite image shows the abundant flow in the Yarkant River while the river is almost dried up in the satellite images of later years. The trend of the decrease in the Hotan River flow is recognized although not so dramatic as that of the Yarkant River.
基金the Project of Demonstration of Walnut Fine Variety Promotion and Standardized Management Technology in the Technology Promotion Demonstration Project of Central Finance Forest and Grass Science in 2020[Xin[2020]No.TG12].
文摘[Objectives]This study was conducted to screen out reasonable pruning methods of walnut,and provide practical guidance for high-yield cultivation of walnut.[Methods]Xinfeng and Xinguang were used to study the effects of mechanical and artificial pruning methods on shoot growth,chlorophyll content in leaves,net photosynthetic rate and fruit quality.[Results]The results showed that:①the pruning method had a significant impact on the number of new shoots,and the number of new shoots of mechanical pruning was significantly higher than that of manual pruning;②the pruning method had a significant impact on the chlorophyll content,and the chlorophyll content of Xinguang of mechanical pruning was significantly higher than that of manual pruning;③the pruning method had a significant impact on the net photosynthetic rate of leaves,and the net photosynthetic rate of manual pruning was significantly higher than that of manual pruning;④Pruning methods had a significant effect on the number of walnut fruit,and the fruit trees pruned manually were significantly higher than those pruned mechanically;⑤the pruning method had no significant impact on the single fruit weight;⑥Pruning methods had a significant effect on the shell yield of a single walnut plant.The shell yield of single walnut plant pruned manually was significantly higher than that pruned mechanically;⑦pruning mode had a significant impact on the yield of walnut per plant,and the yield of artificially pruned walnut per plant was significantly higher than that of mechanical pruning;and⑧Xinfeng s chlorophyll content,net photosynthetic rate,fruit number,shell yield per plant and kernel yield per plant were all better than that of Xinguang,in addition,the growth and development of new shoots,the fruit quantity and quality of fruit also were affected by the interaction effect of genotype and pruning mode×variety.[Conclusions]It can be seen that different pruning methods have significant effects on the growth and development of new shoots and fruit yield a
文摘This paper reviews the recent progress in the understanding of the dynamics of Pb(B_(1/2)B0_(1/2))O_(3)-type relaxor ferroelectrics using of broadband micro-Brillouin scattering spectroscopy,which covers a large frequency range from 1 to 1000 GHz by a tandem multi-pass FabryPerot interferometer.In contrast to Pb(B_(1/3)B0_(2/3))O_(3)-type relaxors,there is no frustration on the B-site of perovskite structure and the degree of order of B-site cations depends on heat treatment.Remarkable softening of sound velocity and an intense central peak are observed above the Curie temperature TC owing to the polarization°uctuations in polar nanoregions(PNRs).Unlike the Pb(B_(1/3)B0_(2/3))O_(3)relaxors,Pb(B_(1/2)B'_(1/2))O_(3)does not undergoes a typical diffuse phase transition without lead vacancies on A-site which enhances randomfields.For the(1-x)Pb(B_(1/2)B'_(1/2))O_(3-x)PbTiO_(3)solid solutions,the long range polar order increases as the PbTiO_(3)content increases.Nevertheless,a central peak owing to dynamic PNRs still remains even for the composition near the MPB,and a critical slowing down is clearly observed in the vicinity of TC.
基金supported by the National Natural Science Foundation of China(No.11761066)。
文摘In this paper,we investigate a deteriorating system with single vacation of a repairman.The system is described by infinite differential-integral equations with boundary conditions.Firstly,by using functional analysis methods,especially linear operator’s C;-semigroup theory,we prove the well-posedness of the system and the existence of a unique positive dynamic solution that satisfies probability condition.Next,by analyzing the spectral properties of the system operator,we prove that all points on the imaginary axis except zero belong to the resolvent set of the system operator.Lastly,we prove that zero is not an eigenvalue of the system operator,which implies that the steady-state solution of the system does not exist.
基金sponsored by the Carnegie/Department of Energy Alliance Center(CDAC,DE-FC03-03NA00144)Use of the Advanced Photon Source was supported by the U.S.Department of Energy under Contract No.DE-AC02-06CH11357+1 种基金HPCAT operations are supported by CIW,CDAC,UNLV,and LLNL through funding from DOENNSA and DOE-BES,with partial instrumentation funding by NSF.M.A.acknowledges ONR grants N00014-14-1-0561.S.P.acknowledges ONR grants N00014-12-1-1034The computations were possible,thanks to the Arkansas High Performance Computer Center at University of Arkansas.S.P.also appreciates Russian Foundation for Basic Research Grant No.14-02-90438_Ucr_a.
文摘Room-temperature Raman scattering and x-ray difraction measurements together with first principles calculations were employed to invetigate the behavior of disordered Pb(In_(1/2)Nb_(1/2))O_(3)(PIN)under pressure up to 50GPa.Raman spectra show broad bands but a peak near the 380cm^(-1) increases its intensity with pressure.The linewidth of the band at 550cm^(-1) also increases with pressure,while two of the Raman peaks merge above 6GPa.Above 16 GPa,we observe additional splitting of the band at 50cm^(-1).The pressure evolution of the diffraction patterns for PIN shows obvious Bragg peaks splitting above 16GPa;consistent with a symmetry lowering transition.The transition at 0.5 GPa is identified as a pseudo-cubic to orthorhombic(Pbam)structural change whereas the transition at 16GPa is istructure and associated with changes in linear compresibility and octahedral titling,and the transition at 30 GPa is associated to an orthorhombic to monoclinic change.First-principles calculations indicate that the Pbam structure is ground state with antiferrodisdortion consistent with experiment.
