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A method of calculating the continuously variable crown work roll contour and the relevant constraint conditions under CVC cyclical shifting mode are proposed. The finite element model is built to calculate the roll gap crowns and the adjustment coefficients of bending force for different strip widths. Improvement in the continuously variable crown work roll contour has been implemented on the 1800-mm compact strip production line. This has resulted in the shifting stroke for the main strip width increasing by 30 %, the work roll wear being more uniform and the strip cross-section shape being better. The qualified rate of strip crown has risen from 98 to 99.5 %, and the qualified rate of strip head flatness has increased from 80 to 91 %.

A method of calculating the continuously variable crown work roll contour and the relevant constraint conditions under CVC cyclical shifting mode are proposed. The finite element model is built to calculate the roll gap crowns and the adjustment coefficients of bending force for different strip widths. Improvement in the continuously variable crown work roll contour has been implemented on the 1800-mm compact strip production line. This has resulted in the shifting stroke for the main strip width increasing by 30 %, the work roll wear being more uniform and the strip cross-section shape being better. The qualified rate of strip crown has risen from 98 to 99.5 %, and the qualified rate of strip head flatness has increased from 80 to 91 %.

A method of calculating the continuously variable crown work roll contour and the relevant constraint conditions under CVC cyclical shifting mode are proposed. The finite element model is built to calculate the roll gap crowns and the adjustment coefficients of bending force for different strip widths. Improvement in the continuously variable crown work roll contour has been implemented on the 1800-mm compact strip production line. This has resulted in the shifting stroke for the main strip width increasing by 30 %, the work roll wear being more uniform and the strip cross-section shape being better. The qualified rate of strip crown has risen from 98 to 99.5 %, and the qualified rate of strip head flatness has increased from 80 to 91 %.

A method of calculating the continuously variable crown work roll contour and the relevant constraint conditions under CVC cyclical shifting mode are proposed. The finite element model is built to calculate the roll gap crowns and the adjustment coefficients of bending force for different strip widths. Improvement in the continuously variable crown work roll contour has been implemented on the 1800-mm compact strip production line. This has resulted in the shifting stroke for the main strip width increasing by 30 %, the work roll wear being more uniform and the strip cross-section shape being better. The qualified rate of strip crown has risen from 98 to 99.5 %, and the qualified rate of strip head flatness has increased from 80 to 91 %.

In this paper, we propose a mechanism to achieve multi-user (MU) MIMO downlink spatial diversity gain for both frequency flat and selective fading channel. The MU interference is first cancelled by precoding the signal with the null space (basis) of other users' propagation space and then the diversity gain is achieved by using the dominant eigen transmission (DET) method on the composite space of the regular MIMO space and the MU interference null space. We prove both in theory and simulations that a diversity gain of an order equal to Nknk is achieved for MU MIMO, where Nk is the # of Rx antennas at the MS and nk is the rank of the MU interference null space. When nk > 1 and Nk= 1, DET reduces to transmit maximal ratio combining (TMRC). When nk= 1 and Nk > 1, DET reduces to receive MRC (RMRC). Selection combining (SC) can also be applied to MU SIMO or MU MISO. © 2015 IEEE.

In this paper, we propose a mechanism to achieve multi-user (MU) MIMO downlink spatial diversity gain for both frequency flat and selective fading channel. The MU interference is first cancelled by precoding the signal with the null space (basis) of other users' propagation space and then the diversity gain is achieved by using the dominant eigen transmission (DET) method on the composite space of the regular MIMO space and the MU interference null space. We prove both in theory and simulations that a diversity gain of an order equal to Nknk is achieved for MU MIMO, where Nk is the # of Rx antennas at the MS and nk is the rank of the MU interference null space. When nk > 1 and Nk= 1, DET reduces to transmit maximal ratio combining (TMRC). When nk= 1 and Nk > 1, DET reduces to receive MRC (RMRC). Selection combining (SC) can also be applied to MU SIMO or MU MISO. © 2015 IEEE.

In this study polyphosphate lubricant was introduced into steel rolling process. The friction coefficient reduced from 0.463 to 0.238 by the presence of polyphosphate lubricant as compared with unlubricated condition, calculated from 2-high Hille 100 rolling mill tests. A tribofilm of similar to 100 nm can be observed on the strip surface, greatly improving the surface finish. This tribofilm well adhered on the oxide layer/steel base by the interfacial reactions. Laser-scanning confocal microscope well confirmed the reactions of polyphosphate lubricant with the oxide scales occurring. Furthermore, a feasible mechanism the composition and structure of this lubricant during thermal reaction was proposed when exposed to different temperatures. (C) 2015 Elsevier B.V. All rights reserved.

In this paper, we propose a mechanism to achieve multi-user (MU) MIMO downlink spatial diversity gain for both frequency flat and selective fading channel. The MU interference is first cancelled by precoding the signal with the null space (basis) of other users' propagation space and then the diversity gain is achieved by using the dominant eigen transmission (DET) method on the composite space of the regular MIMO space and the MU interference null space. We prove both in theory and simulations that a diversity gain of an order equal to Nknk is achieved for MU MIMO, where Nk is the # of Rx antennas at the MS and nk is the rank of the MU interference null space. When nk > 1 and Nk= 1, DET reduces to transmit maximal ratio combining (TMRC). When nk= 1 and Nk > 1, DET reduces to receive MRC (RMRC). Selection combining (SC) can also be applied to MU SIMO or MU MISO.

Polyphosphate inorganic polymer is evaluated as a high-performance lubricant for steel/steel contacts at 600, 700, and 800 degrees C. In situ thermal tests of this lubricant indicate that liquid lubrication at the rubbing interface is occurring. Tribological testing indicates the molten polyphosphate is effective as a lubricant and, reduces friction and wear of the sliding steel/steel tribo pair substantially. The lubricated steel/steel pair shows desirable tribological performance that correlates closely with the temperature-dependent hierarchical structure of the tribo-interface under the combination of pressure, shear, and temperature. Morphological observation of worn surfaces and interfaces of steel discs is achieved using scanning electron microscopy and transmission electron microscopy (TEM). Compositional analysis and elemental distribution are performed using X-ray photoelectron spectroscopy and energy dispersive X-ray on a scanning TEM. These enable the tribochemical reactions at the rubbing surface and the formation mechanism of the hierarchical tribo-interface to be understood.

A new class of high temperature lubricant of inorganic alkali metal polyphosphate was developed for hot metal forming, which involved a fundamental knowledge of melt lubrication. At elevated temperature a 55% reduction in friction and a 50% decrease in wear were achieved by the presence of the molten polyphosphate lubrication, as well as the excellent anti-oxidation capability at the rubbing steel/steel interface, which closely correlated with the tribo-induced hierarchical structure at the rubbing interface. This inorganic polyphosphate lubricant can be called a smart polymeric material, which will be an eco-friendly alternative for high temperature applications. This journal is

Two new alkaloids, longphyllinesides A (1) and B (2), were isolated from Daphniphyllum longeracemosum. Their structures were elucidated using 1D and 2D NMR spectra. The key step in their biogenetic pathway is indicated to be Diels-Alder cycloaddition via asynchronous concerted mechanism by density functional theory calculations. The possibility of involvement of a Diels-Alderase is also discussed. (C) 2014 Elsevier Ltd. All rights reserved.

In order to analyze the mechanical behaviour of ultra-low carbon steel in warm rolling, the flow stress and pyroplastric behaviour were investigated on the Gleeble-3500 with the deformation temperatures in the warm range. The strain rates of 0.1, 1 and 10s-1 were applied to the temperatures above. A series of stress-strain curves were obtained after the compression Gleeble tests with different parameters. The result indicates the flow stress increases with the decreasing deformation temperatures during the compression. And it increases with the increasing strain rate as well. The constitutive equation, which includes the deformation activation energy Q and the Kelvin temperature T, was developed by using the concept that proposed by C. M. Sellars and W.J. M. Tegart. These equation results can be verified by the results of Gleeble compression test. It indicates the average error is reasonable and acceptable for predicting the flow stress and pyroplastic deformation behaviour of ultra-low carbon steel in warm temperature range. The achieved constitutive equation provides theoretical fundaments for designing the warm rolling process of ultra-low carbon steel. The experimental data also can be used as material property parameters for the establishment of finite element (FE) model. (2014) Trans Tech Publications, Switzerland.

Ferrite rolling of interstitial free steel strip in the temperature range 650-850°C can effectively reduce furnace costs and scale formation as a result of lower strip reheating temperatures. Different lubrication conditions of lubricating oil, solid lubricant and dry condition were used during ferrite rolling tests of thin interstitial free steel strip on a 2-high Hille 100 experimental rolling mill. Different rolling speed, rolling temperature and reductions were applied to the rolling process. The rolling force and roll roughness were affected by the lubrication conditions and rolling parameters. Solid lubricant indicated an improved performance in terms of the roll roughness, as well as the oxidation property of the strip surface during ferrite rolling.

In order to analyze the mechanical behaviour of ultra-low carbon steel in warm rolling, the flow stress and pyroplastric behaviour were investigated on the Gleeble-3500 with the deformation temperatures in the warm range. The strain rates of 0.1, 1 and 10s-1 were applied to the temperatures above. A series of stress-strain curves were obtained after the compression Gleeble tests with different parameters. The result indicates the flow stress increases with the decreasing deformation temperatures during the compression. And it increases with the increasing strain rate as well. The constitutive equation, which includes the deformation activation energy Q and the Kelvin temperature T, was developed by using the concept that proposed by C. M. Sellars and W.J. M. Tegart. These equation results can be verified by the results of Gleeble compression test. It indicates the average error is reasonable and acceptable for predicting the flow stress and pyroplastic deformation behaviour of ultra-low carbon steel in warm temperature range. The achieved constitutive equation provides theoretical fundaments for designing the warm rolling process of ultra-low carbon steel. The experimental data also can be used as material property parameters for the establishment of finite element (FE) model. (2014) Trans Tech Publications, Switzerland.

Ferrite rolling of interstitial free steel strip in the temperature range 650-850°C can effectively reduce furnace costs and scale formation as a result of lower strip reheating temperatures. Different lubrication conditions of lubricating oil, solid lubricant and dry condition were used during ferrite rolling tests of thin interstitial free steel strip on a 2-high Hille 100 experimental rolling mill. Different rolling speed, rolling temperature and reductions were applied to the rolling process. The rolling force and roll roughness were affected by the lubrication conditions and rolling parameters. Solid lubricant indicated an improved performance in terms of the roll roughness, as well as the oxidation property of the strip surface during ferrite rolling.

In order to analyze the mechanical behaviour of ultra-low carbon steel in warm rolling, the flow stress and pyroplastric behaviour were investigated on the Gleeble-3500 with the deformation temperatures in the warm range. The strain rates of 0.1, 1 and 10s-1 were applied to the temperatures above. A series of stress-strain curves were obtained after the compression Gleeble tests with different parameters. The result indicates the flow stress increases with the decreasing deformation temperatures during the compression. And it increases with the increasing strain rate as well. The constitutive equation, which includes the deformation activation energy Q and the Kelvin temperature T, was developed by using the concept that proposed by C. M. Sellars and W.J. M. Tegart. These equation results can be verified by the results of Gleeble compression test. It indicates the average error is reasonable and acceptable for predicting the flow stress and pyroplastic deformation behaviour of ultra-low carbon steel in warm temperature range. The achieved constitutive equation provides theoretical fundaments for designing the warm rolling process of ultra-low carbon steel. The experimental data also can be used as material property parameters for the establishment of finite element (FE) model. (2014) Trans Tech Publications, Switzerland.

Ferrite rolling of interstitial free steel strip in the temperature range 650-850°C can effectively reduce furnace costs and scale formation as a result of lower strip reheating temperatures. Different lubrication conditions of lubricating oil, solid lubricant and dry condition were used during ferrite rolling tests of thin interstitial free steel strip on a 2-high Hille 100 experimental rolling mill. Different rolling speed, rolling temperature and reductions were applied to the rolling process. The rolling force and roll roughness were affected by the lubrication conditions and rolling parameters. Solid lubricant indicated an improved performance in terms of the roll roughness, as well as the oxidation property of the strip surface during ferrite rolling.

In order to analyze the mechanical behaviour of ultra-low carbon steel in warm rolling, the flow stress and pyroplastric behaviour were investigated on the Gleeble-3500 with the deformation temperatures in the warm range. The strain rates of 0.1, 1 and 10s-1 were applied to the temperatures above. A series of stress-strain curves were obtained after the compression Gleeble tests with different parameters. The result indicates the flow stress increases with the decreasing deformation temperatures during the compression. And it increases with the increasing strain rate as well. The constitutive equation, which includes the deformation activation energy Q and the Kelvin temperature T, was developed by using the concept that proposed by C. M. Sellars and W.J. M. Tegart. These equation results can be verified by the results of Gleeble compression test. It indicates the average error is reasonable and acceptable for predicting the flow stress and pyroplastic deformation behaviour of ultra-low carbon steel in warm temperature range. The achieved constitutive equation provides theoretical fundaments for designing the warm rolling process of ultra-low carbon steel. The experimental data also can be used as material property parameters for the establishment of finite element (FE) model. (2014) Trans Tech Publications, Switzerland.

Ferrite rolling of interstitial free steel strip in the temperature range 650-850°C can effectively reduce furnace costs and scale formation as a result of lower strip reheating temperatures. Different lubrication conditions of lubricating oil, solid lubricant and dry condition were used during ferrite rolling tests of thin interstitial free steel strip on a 2-high Hille 100 experimental rolling mill. Different rolling speed, rolling temperature and reductions were applied to the rolling process. The rolling force and roll roughness were affected by the lubrication conditions and rolling parameters. Solid lubricant indicated an improved performance in terms of the roll roughness, as well as the oxidation property of the strip surface during ferrite rolling.

Two new alkaloids, longphyllinesides A (1) and B (2), were isolated from Daphniphyllum longeracemosum. Their structures were elucidated using 1D and 2D NMR spectra. The key step in their biogenetic pathway is indicated to be Diels-Alder cycloaddition via asynchronous concerted mechanism by density functional theory calculations. The possibility of involvement of a Diels-Alderase is also discussed. (C) 2014 Elsevier Ltd. All rights reserved.

In order to solve the serious backup roll spalling of roughing mill during ultra-wide stainless steel rolling process, a 3D elastic deformation finite element model of 4-high roll stacks was established for simulating the mechanical behavior during the hot rolling process. The asymmetric contact pressure between backup and work rolls is the key factor for the frequent roll spalling accidents. Based on the principle of homogenizing contact pressure between rolls, minimizing harmful contact zone in different strip widths and considering roll wearing as a whole, SCR (Smart Contact Backup Rolls) was developed. The simulation reveals when using the SMS200 backup roll contour, the peak position of contact pressure keeps consistent with the practical spalling position. Instead, the peak value of the roll contact pressure with SCR technology decreases significantly with various strip widths. The unevenness coefficients of roll contact pressure with SCR technology decline sharply from 1.36 and more to less than 1.18 with different strip widths. The roll consumption decreases from 0.1254kg/t to 0.055kg/t. During the continuous strip production of 20 million tons and more, non-occurring backup roll spalling, uniform roll wear and remarkable decrease in roll consumption have been validated by long-term industrial applications of the 2250 hot strip mill.

This thesis aims to investigate the tribological behaviours of the rubbing steel/steel pairs with a proposed polyphosphate lubricant at the temperatures of ferrite rolling and the effect of lubrication on the texture of interstitial free (IF) steel which is rolled in the ferrite temperature range. As complex tribological reactions at the sliding interface depend on the high load and temperature conditions, the thesis will provide a better insight into the possible tribochemical reactions of the given polyphosphate lubricant system which can reduce friction and wear, minimise oxidation, improve surface quality and texture for better drawability. The flow stress and pyroplastic behaviour of two kinds of IF steels were investigated systematically by the compression tests on Gleeble 3500 Simulator in the ferrite (warm) temperature range. Two different constitutive equations were developed from the experimental results and they can be used to reliably predict the flow stress and pyroplastic deformation behaviour of IF steel under ferrite rolling. The rolling of IF steel indicates a better lubrication performance of the polyphosphate lubricant can be achieved over lubricating oil and unlubricated condition. The influence of polyphosphate lubricant during ferrite rolling process was studied in the ferrite temperature range. Another two different lubrication conditions of lubricating oil and dry conditions were used to compare the lubrication performance with proposed lubricant. The rolling force, friction coefficient, roll and strip roughness and strip oxidation can be improved under lubricated conditions. The polyphosphate lubricant showed a better micro surface roughness than under lubricating oil and dry conditions. The mechanism of inorganic polyphosphate lubricant effect on the steel surface was studied to explain the improved lubrication performance during ferrite rolling of IF steel. A series of high temperature tests which included the in-situ thermal evolution tes

Two new alkaloids, longphyllinesides A (1) and B (2), were isolated from Daphniphyllum longeracemosum. Their structures were elucidated using 1D and 2D NMR spectra. The key step in their biogenetic pathway is indicated to be Diels-Alder cycloaddition via asynchronous concerted mechanism by density functional theory calculations. The possibility of involvement of a Diels-Alderase is also discussed. (C) 2014 Elsevier Ltd. All rights reserved.

This thesis aims to investigate the tribological behaviours of the rubbing steel/steel pairs with a proposed polyphosphate lubricant at the temperatures of ferrite rolling and the effect of lubrication on the texture of interstitial free (IF) steel which is rolled in the ferrite temperature range. As complex tribological reactions at the sliding interface depend on the high load and temperature conditions, the thesis will provide a better insight into the possible tribochemical reactions of the given polyphosphate lubricant system which can reduce friction and wear, minimise oxidation, improve surface quality and texture for better drawability. The flow stress and pyroplastic behaviour of two kinds of IF steels were investigated systematically by the compression tests on Gleeble 3500 Simulator in the ferrite (warm) temperature range. Two different constitutive equations were developed from the experimental results and they can be used to reliably predict the flow stress and pyroplastic deformation behaviour of IF steel under ferrite rolling. The rolling of IF steel indicates a better lubrication performance of the polyphosphate lubricant can be achieved over lubricating oil and unlubricated condition. The influence of polyphosphate lubricant during ferrite rolling process was studied in the ferrite temperature range. Another two different lubrication conditions of lubricating oil and dry conditions were used to compare the lubrication performance with proposed lubricant. The rolling force, friction coefficient, roll and strip roughness and strip oxidation can be improved under lubricated conditions. The polyphosphate lubricant showed a better micro surface roughness than under lubricating oil and dry conditions. The mechanism of inorganic polyphosphate lubricant effect on the steel surface was studied to explain the improved lubrication performance during ferrite rolling of IF steel. A series of high temperature tests which included the in-situ thermal evolution tes

This thesis aims to investigate the tribological behaviours of the rubbing steel/steel pairs with a proposed polyphosphate lubricant at the temperatures of ferrite rolling and the effect of lubrication on the texture of interstitial free (IF) steel which is rolled in the ferrite temperature range. As complex tribological reactions at the sliding interface depend on the high load and temperature conditions, the thesis will provide a better insight into the possible tribochemical reactions of the given polyphosphate lubricant system which can reduce friction and wear, minimise oxidation, improve surface quality and texture for better drawability. The flow stress and pyroplastic behaviour of two kinds of IF steels were investigated systematically by the compression tests on Gleeble 3500 Simulator in the ferrite (warm) temperature range. Two different constitutive equations were developed from the experimental results and they can be used to reliably predict the flow stress and pyroplastic deformation behaviour of IF steel under ferrite rolling. The rolling of IF steel indicates a better lubrication performance of the polyphosphate lubricant can be achieved over lubricating oil and unlubricated condition. The influence of polyphosphate lubricant during ferrite rolling process was studied in the ferrite temperature range. Another two different lubrication conditions of lubricating oil and dry conditions were used to compare the lubrication performance with proposed lubricant. The rolling force, friction coefficient, roll and strip roughness and strip oxidation can be improved under lubricated conditions. The polyphosphate lubricant showed a better micro surface roughness than under lubricating oil and dry conditions. The mechanism of inorganic polyphosphate lubricant effect on the steel surface was studied to explain the improved lubrication performance during ferrite rolling of IF steel. A series of high temperature tests which included the in-situ thermal evolution tes

High pressure torsion (HPT) is an important process for producing ultrafine grained materials, and while numerous experimental investigations of HPT have been carried out, most concentrated on microstructure, texture, or the mechanical properties of the processed materials, while few work has been carried out by using FEM because of extreme mesh distortion during deformation. In this paper, a FEM model of HPT with a mapping solution method of Abaqus has been established and used to investigate the plastic deformation of HPT process, the stress and equivalent strain distribution and evolution along the radius and axial directions were presented, inhomogeneous deformation was observed along the radius and axial directions and a homogenous deformation could be anticipated if the strain applied reached a high enough level. The FEM results agreed quite well with the experimental results. A FEM model with mapping solution method of Abaqus was established and used to investigate the plastic deformation, the stress and equivalent strain distribution and evolution of the HPT process. Inhomogeneous deformation was observed along the radius and axial directions and a homogenous deformation along the whole sample could be anticipated if the strain applied reached a high enough level.

High pressure torsion (HPT) is an important process for producing ultrafine grained materials, and while numerous experimental investigations of HPT have been carried out, most concentrated on microstructure, texture, or the mechanical properties of the processed materials, while few work has been carried out by using FEM because of extreme mesh distortion during deformation. In this paper, a FEM model of HPT with a mapping solution method of Abaqus has been established and used to investigate the plastic deformation of HPT process, the stress and equivalent strain distribution and evolution along the radius and axial directions were presented, inhomogeneous deformation was observed along the radius and axial directions and a homogenous deformation could be anticipated if the strain applied reached a high enough level. The FEM results agreed quite well with the experimental results. A FEM model with mapping solution method of Abaqus was established and used to investigate the plastic deformation, the stress and equivalent strain distribution and evolution of the HPT process. Inhomogeneous deformation was observed along the radius and axial directions and a homogenous deformation along the whole sample could be anticipated if the strain applied reached a high enough level.

High pressure torsion (HPT) is an important process for producing ultrafine grained materials, and while numerous experimental investigations of HPT have been carried out, most concentrated on microstructure, texture, or the mechanical properties of the processed materials, while few work has been carried out by using FEM because of extreme mesh distortion during deformation. In this paper, a FEM model of HPT with a mapping solution method of Abaqus has been established and used to investigate the plastic deformation of HPT process, the stress and equivalent strain distribution and evolution along the radius and axial directions were presented, inhomogeneous deformation was observed along the radius and axial directions and a homogenous deformation could be anticipated if the strain applied reached a high enough level. The FEM results agreed quite well with the experimental results. A FEM model with mapping solution method of Abaqus was established and used to investigate the plastic deformation, the stress and equivalent strain distribution and evolution of the HPT process. Inhomogeneous deformation was observed along the radius and axial directions and a homogenous deformation along the whole sample could be anticipated if the strain applied reached a high enough level.

Here we report the rescue of a recombinant porcine reproductive and respiratory syndrome virus (PRRSV) carrying an enhanced green fluorescent protein (EGFP) reporter gene as a separate transcription unit. A copy of the transcription regulatory sequence for ORF6 (TRS6) was inserted between the N protein and 3′-UTR to drive the transcription of the EGFP gene and yield a general purpose expression vector. Successful recovery of PRRSV was obtained using an RNA polymerase II promoter to drive transcription of the full-length virus genome, which was assembled in a bacterial artificial chromosome (BAC). The recombinant virus showed growth replication characteristics similar to those of the wild-type virus in the infected cells. In addition, the recombinant virus stably expressed EGFP for at least 10 passages. EGFP expression was detected at approximately 10 h post infection by live-cell imaging to follow the virus spread in real time and the infection of neighbouring cells occurred predominantly through cell-to-cell-contact. Finally, the recombinant virus generated was found to be an excellent tool for neutralising antibodies and antiviral compound screening. The newly established reverse genetics system for PRRSV could be a useful tool not only to monitor virus spread and screen for neutralising antibodies and antiviral compounds, but also for fundamental research on the biology of the virus.

High pressure torsion (HPT) is an important process for producing ultrafine grained materials, and while numerous experimental investigations of HPT have been carried out, most concentrated on microstructure, texture, or the mechanical properties of the processed materials, while few work has been carried out by using FEM because of extreme mesh distortion during deformation. In this paper, a FEM model of HPT with a mapping solution method of Abaqus has been established and used to investigate the plastic deformation of HPT process, the stress and equivalent strain distribution and evolution along the radius and axial directions were presented, inhomogeneous deformation was observed along the radius and axial directions and a homogenous deformation could be anticipated if the strain applied reached a high enough level. The FEM results agreed quite well with the experimental results. A FEM model with mapping solution method of Abaqus was established and used to investigate the plastic deformation, the stress and equivalent strain distribution and evolution of the HPT process. Inhomogeneous deformation was observed along the radius and axial directions and a homogenous deformation along the whole sample could be anticipated if the strain applied reached a high enough level.