The colored poly(m-phenylene isophthalamide)(PMIA)spinning solution was prepared by wet spinning and the die-swell of the colored PMIA spinning solution was done when it was extruded from a die in this experiment.The ...The colored poly(m-phenylene isophthalamide)(PMIA)spinning solution was prepared by wet spinning and the die-swell of the colored PMIA spinning solution was done when it was extruded from a die in this experiment.The properties and structures of colored PMIA fibers were characterized by scanning electron microscopy(SEM).The colored PMIA spinning dopes were first commixed in a pressurizer and then spun into a coagulation bath.The effect of die swell on the colored PMIA solution was resulted from the viscoelastic properties of the colored PMIA solution in the spinning process.The results showed that the die-swell ratio of the colored PMIA solution increased linearly with increasing the pressure and die length/diameter ratio(L/D).At the same pressure and L/D,the die-swell ratio decreased with the increase of filter layers and temperature.Also,optimized spinning parameters of the dopedyed PMIA fiber were obtained.展开更多
Research on the diffusion characteristics of swells contributes positively to wave energy forecasting, swell monitoring, and early warning. In this work, the South Indian Ocean westerly index(SIWI) and Indian Ocean sw...Research on the diffusion characteristics of swells contributes positively to wave energy forecasting, swell monitoring, and early warning. In this work, the South Indian Ocean westerly index(SIWI) and Indian Ocean swell diffusion effect index(IOSDEI) are defined on the basis of the 45-year(September 1957–August 2002) ERA-40 wave reanalysis data from the European Centre for Medium-Range Weather Forecasts(ECMWF) to analyze the impact of the South Indian Ocean westerlies on the propagation of swell acreage. The following results were obtained: 1) The South Indian Ocean swell mainly propagates from southwest to northeast. The swell also spreads to the Arabian Sea upon reaching low-latitude waters. The 2.0-meter contour of the swell can reach northward to Sri Lankan waters. 2) The size of the IOSDEI is determined by the SIWI strength. The IOSDEI requires approximately 2–3.5 days to fully respond to the SIWI. The correlations between SIWI and IOSDEI show obvious seasonal differences, with the highest correlations found in December–January–February(DJF) and the lowest correlations observed in June–July–August(JJA). 3) The SIWI and IOSDEI have a common period of approximately 1 week in JJA and DJF. The SIWI leads by approximately 2–3 days in this common period.展开更多
Thermal conductivity, water retention curve and swelling behavior of two MX80 bentonite samples were studied in the present work. The difference obtained from these two MX80 bentonite samples was then analyzed in term...Thermal conductivity, water retention curve and swelling behavior of two MX80 bentonite samples were studied in the present work. The difference obtained from these two MX80 bentonite samples was then analyzed in terms of mineralogical effects (effects of the proportion of quartz and montmorillonite). It was concluded that the mineralogical effect was significant on the thermal conductivity and the swelling capacity; on the contrary, it was negligible on the water retention property.展开更多
The Impact of Swelling Indices of Sokoto Clays on the Moulding Properties of the Clays in Sand Mixtures was investi- gated. Four clays (labeled A, B, C, D) from different locations in Sokoto state of Nigeria were samp...The Impact of Swelling Indices of Sokoto Clays on the Moulding Properties of the Clays in Sand Mixtures was investi- gated. Four clays (labeled A, B, C, D) from different locations in Sokoto state of Nigeria were sampled. The sampling method was that for each deposit five samples were taken at different positions and then mixed together. At the labora- tory they were washed to remove organic matter and then dried at 110°C in the oven. A laboratory ball mill was used to grind the dried clays. Each of the clay was then sampled for the determination of its swelling index. The determination of the moulding properties of the clays then followed. Only green compression strength, dry compression strength and green permeability, moulding properties were determined. The analysis of the result revealed that clay B has the highest green and dry strength values it had the highest green compression strength of 71.7 KN/m2 and the highest dry com- pression strength of 3225.75 KN/m2. Clay B also has the highest swelling index of 60% and very high degree of expan- siveness when compared to the other three clays. Clay B was followed by clay A with swelling index of 25%;the clay has high green and dry compression strength and a moderate degree of expansiveness. The inability of clay D with swelling index of 40% to be the next clay to clay B which has the highest swelling index of 60% among the four clays in terms of good moulding properties is an indication that high swelling index does not always mean good moulding properties in clay binders.展开更多
This paper examines the effective stress in indurated clay rock theoretically and experimentally.A stress concept is derived from the analysis of the microstructure and of the pore water in the highly-indurated Callov...This paper examines the effective stress in indurated clay rock theoretically and experimentally.A stress concept is derived from the analysis of the microstructure and of the pore water in the highly-indurated Callovo-Oxfordian and Opalinus clay rocks,and subsequently validated by various experiments performed on these claystones.The concept suggests that the interparticle or effective stress in a dense clay ewater system is transferred through both the adsorbed interparticle pore water in narrow pores and the solidesolid contact between non-clay mineral grains.The experiments show that the adsorbed pore water in the claystones is capable of bearing deviatoric effective stresses up to the failure strength.The applied stresses are for the most part or even totally transferred by the bound pore water,i.e.the swelling pressure in the interparticle bound pore water is almost equivalent to the effective stress.This stress concept provides a reasonable view to the nature of the effective stress in argillaceous rock and forms the fundamental basis for studies of the hydro-mechanical properties and processes in clay formations.展开更多
We investigated the influence of the in-medium nucleon swelling on pion-nu-cleus scattering at energy above the Δ<sub>33</sub> resonance.An increased theoretical π<sup>+</sup>-<sup>12&l...We investigated the influence of the in-medium nucleon swelling on pion-nu-cleus scattering at energy above the Δ<sub>33</sub> resonance.An increased theoretical π<sup>+</sup>-<sup>12</sup>Cdifferential cross section at 800 MeV/c was found as a result of the nucleon swellingeffect.展开更多
In this paper exit.bend angle(tea-pot effect)has been analysed theoretically based on thebasic)aw of hydromechanics.It was proved that it is the transverse shear stress that causes exitbend angle while the bending dir...In this paper exit.bend angle(tea-pot effect)has been analysed theoretically based on thebasic)aw of hydromechanics.It was proved that it is the transverse shear stress that causes exitbend angle while the bending direction is along with the resultant force of the shear stresses andthe magnitude of the exit angle is directly proportional to the resultant force.The equation re·lating exit bend angle with the resultant force was set up and experiment verification of theequation was carried out with rational agreement to theoretical results.展开更多
文摘The colored poly(m-phenylene isophthalamide)(PMIA)spinning solution was prepared by wet spinning and the die-swell of the colored PMIA spinning solution was done when it was extruded from a die in this experiment.The properties and structures of colored PMIA fibers were characterized by scanning electron microscopy(SEM).The colored PMIA spinning dopes were first commixed in a pressurizer and then spun into a coagulation bath.The effect of die swell on the colored PMIA solution was resulted from the viscoelastic properties of the colored PMIA solution in the spinning process.The results showed that the die-swell ratio of the colored PMIA solution increased linearly with increasing the pressure and die length/diameter ratio(L/D).At the same pressure and L/D,the die-swell ratio decreased with the increase of filter layers and temperature.Also,optimized spinning parameters of the dopedyed PMIA fiber were obtained.
基金supported by the National Key R&D Program (No.2017YFC1405103)the Joint Funds of the National Natural Science Foundation of China (No.U170 6220)+1 种基金the National Natural Science Foundation of China (Nos.41901006, 41471005, and 41271016)the Natural Science Foundation of Shandong Province (No.ZR 2019BD005)。
文摘Research on the diffusion characteristics of swells contributes positively to wave energy forecasting, swell monitoring, and early warning. In this work, the South Indian Ocean westerly index(SIWI) and Indian Ocean swell diffusion effect index(IOSDEI) are defined on the basis of the 45-year(September 1957–August 2002) ERA-40 wave reanalysis data from the European Centre for Medium-Range Weather Forecasts(ECMWF) to analyze the impact of the South Indian Ocean westerlies on the propagation of swell acreage. The following results were obtained: 1) The South Indian Ocean swell mainly propagates from southwest to northeast. The swell also spreads to the Arabian Sea upon reaching low-latitude waters. The 2.0-meter contour of the swell can reach northward to Sri Lankan waters. 2) The size of the IOSDEI is determined by the SIWI strength. The IOSDEI requires approximately 2–3.5 days to fully respond to the SIWI. The correlations between SIWI and IOSDEI show obvious seasonal differences, with the highest correlations found in December–January–February(DJF) and the lowest correlations observed in June–July–August(JJA). 3) The SIWI and IOSDEI have a common period of approximately 1 week in JJA and DJF. The SIWI leads by approximately 2–3 days in this common period.
文摘Thermal conductivity, water retention curve and swelling behavior of two MX80 bentonite samples were studied in the present work. The difference obtained from these two MX80 bentonite samples was then analyzed in terms of mineralogical effects (effects of the proportion of quartz and montmorillonite). It was concluded that the mineralogical effect was significant on the thermal conductivity and the swelling capacity; on the contrary, it was negligible on the water retention property.
文摘The Impact of Swelling Indices of Sokoto Clays on the Moulding Properties of the Clays in Sand Mixtures was investi- gated. Four clays (labeled A, B, C, D) from different locations in Sokoto state of Nigeria were sampled. The sampling method was that for each deposit five samples were taken at different positions and then mixed together. At the labora- tory they were washed to remove organic matter and then dried at 110°C in the oven. A laboratory ball mill was used to grind the dried clays. Each of the clay was then sampled for the determination of its swelling index. The determination of the moulding properties of the clays then followed. Only green compression strength, dry compression strength and green permeability, moulding properties were determined. The analysis of the result revealed that clay B has the highest green and dry strength values it had the highest green compression strength of 71.7 KN/m2 and the highest dry com- pression strength of 3225.75 KN/m2. Clay B also has the highest swelling index of 60% and very high degree of expan- siveness when compared to the other three clays. Clay B was followed by clay A with swelling index of 25%;the clay has high green and dry compression strength and a moderate degree of expansiveness. The inability of clay D with swelling index of 40% to be the next clay to clay B which has the highest swelling index of 60% among the four clays in terms of good moulding properties is an indication that high swelling index does not always mean good moulding properties in clay binders.
基金funded by the German Federal Ministry of Economics and Technology (BMWi) under contract 02E10377
文摘This paper examines the effective stress in indurated clay rock theoretically and experimentally.A stress concept is derived from the analysis of the microstructure and of the pore water in the highly-indurated Callovo-Oxfordian and Opalinus clay rocks,and subsequently validated by various experiments performed on these claystones.The concept suggests that the interparticle or effective stress in a dense clay ewater system is transferred through both the adsorbed interparticle pore water in narrow pores and the solidesolid contact between non-clay mineral grains.The experiments show that the adsorbed pore water in the claystones is capable of bearing deviatoric effective stresses up to the failure strength.The applied stresses are for the most part or even totally transferred by the bound pore water,i.e.the swelling pressure in the interparticle bound pore water is almost equivalent to the effective stress.This stress concept provides a reasonable view to the nature of the effective stress in argillaceous rock and forms the fundamental basis for studies of the hydro-mechanical properties and processes in clay formations.
基金The project supported by the National Natural Science Foundation of China and the Grant of Nankai University
文摘We investigated the influence of the in-medium nucleon swelling on pion-nu-cleus scattering at energy above the Δ<sub>33</sub> resonance.An increased theoretical π<sup>+</sup>-<sup>12</sup>Cdifferential cross section at 800 MeV/c was found as a result of the nucleon swellingeffect.
文摘In this paper exit.bend angle(tea-pot effect)has been analysed theoretically based on thebasic)aw of hydromechanics.It was proved that it is the transverse shear stress that causes exitbend angle while the bending direction is along with the resultant force of the shear stresses andthe magnitude of the exit angle is directly proportional to the resultant force.The equation re·lating exit bend angle with the resultant force was set up and experiment verification of theequation was carried out with rational agreement to theoretical results.