The problem with earth constructions is their low resistance to water. Step by step, the water degrades the exterior facings of the structures and ends up creating zones of weakness through the structures, making them...The problem with earth constructions is their low resistance to water. Step by step, the water degrades the exterior facings of the structures and ends up creating zones of weakness through the structures, making them collapse and creating enormous socio-economic problems, especially in rural areas. The solutions proposed to date, like the use of straw, cow dung, boiled skins, banana leaves, tar, cement soil, have shown their limits. Generally, the poor adhesion between the protected material and the protective layer means that the latter always ends up peeling off. This work, which is inspired by the traditional practice where plant tannins are used to brush the earthen walls to waterproof them, proposes a tri-layer coating composed of soil, powder and hydrolysable tannins extracted from the stem bark of Bridelia. This work focuses on the geotechnical characterization of the soil, the extraction of hydrolysable tannin, the manufacture of the micro-coating, the resistance tests carried out on the micro-coating, the technique of implementation and the test of evaluation of the performance of the tri-layer coating. The results obtained show that not only does the tri-layer coating adhere perfectly to the layer to protect, but it also waterproofs it and protects it against shocks.展开更多
One purpose of this study was to develop a paliperidone(PAL)tri-layer ascending release pushepull osmotic pump(TA-PPOP)tablet which could meet the needs of clinical applications.And another purpose was to investigate ...One purpose of this study was to develop a paliperidone(PAL)tri-layer ascending release pushepull osmotic pump(TA-PPOP)tablet which could meet the needs of clinical applications.And another purpose was to investigate whether different coating materials influenced in vivo performance of TA-PPOP.The ascending release mechanism of this trilayer delivery system on theory was elaborated.TA-PPOP was prepared by means of coating with cellulose acetate(CA)or ethyl cellulose(EC).Several important influence factors such as different core tablet compositions and different coating solution ingredients involved in the formulation procedure were investigated.The optimization of formulation and process was conducted by comparing different in vitro release behaviors of PAL.In vitro dissolution studies indicated that both the two formulations of different coating materials were able to deliver PAL at an ascending release rate during the whole 24 h test.The in vivo pharmacokinetics study showed that both self-made PPOP tablets with different coating had a good in vitro-in vivo correlation(IVIVC)and were bioequivalent with the brand product,which demonstrated no significant influence of the coating materials on the in vivo release acceleration of TA-PPOP.展开更多
The Fe_3O_4/Fe/Fe_3O_4 (MIM) tri-layer films (200 nm/12-93 nm/200 um) were prepared on Si(100) by DC-magnetron reactive-sputtering followed by air- or vacuum-annealing at 280-400℃ for 1.5 h, respectively. Magnetic pr...The Fe_3O_4/Fe/Fe_3O_4 (MIM) tri-layer films (200 nm/12-93 nm/200 um) were prepared on Si(100) by DC-magnetron reactive-sputtering followed by air- or vacuum-annealing at 280-400℃ for 1.5 h, respectively. Magnetic properties and phases under different sandwich and annealing conditions were studied. In MIM structure, the incorporation of the interlayer iron does increase the magnetization measured under 8 kOe (M_8K), but reduce coercivity (H_c). The H_c of asdeposited films decreases from 354 Oe to 74 Oe; while M_8K increases from 254 to 392 emu/cc. By annealing in air, the whole MIM tri-layer film becomes γ-F_e2O_3, H_c is about 550 O_e and M_8K is around 250 emu/cc. The coercivity mechanism of as-deposited and annealed MIM trilayer films belongs to domain-wall pinning type. δM plots show that when the interlayer Fe thickness is 12 um, the Fe and Fe_3O_4 layers are decoupled in the as-deposited and annealed states; while it is coupled in the as deposited state when the Fe thickness increases to 23 um. Vacuum annealing of the MIM films leads to increase in both coercivity and magnetization, and to enhance the exchange coupling between layers.展开更多
Sensitive magnetic field sensor with good performances can be fabricated utilizing the giant magneto-impedance (GMI) effect of soft magnetic multi-layer thin films. The transverse and longitudinal GMI effect in patter...Sensitive magnetic field sensor with good performances can be fabricated utilizing the giant magneto-impedance (GMI) effect of soft magnetic multi-layer thin films. The transverse and longitudinal GMI effect in patterned FeSiB/Cu/FeSiB tri-layer films with the change of external magnetic field and frequency were studied at the same time. The change of the impedance of the films with the external magnetic fieldand frequency was shown. Comparing the longitudinal and transverse effect, the transverse effect has a larger linear range from zero magnetic field to a quite large magnetic field at all frequencies, and the change still were not saturated until the external magnetic field reached 1.2×104A/m, which illustrated that the films can be utilized to detect larger magnetic fields than now presented GMI sensors.展开更多
Hollow poly（divinylbenzene-co-methacrylic acid） （P（DVB-co-MAA）） microspheres were prepared by the selective dissolution of the non-crosslinked poly（methacrylic acid） （PMAA） mid-layer in ethanol from the corr...Hollow poly（divinylbenzene-co-methacrylic acid） （P（DVB-co-MAA）） microspheres were prepared by the selective dissolution of the non-crosslinked poly（methacrylic acid） （PMAA） mid-layer in ethanol from the corresponding silica/PMAA/P（DVB-co-MAA） tri-layer hybrid microspheres, which were afforded by a three-stage reaction. Silica/PMAA core-shell hybrid microspheres were prepared by the second-stage distillation polymerization of methacrylic acid （MAA） via the capture of the oligomers and monomers with the aid of the vinyl groups on the surface of 3-（methacryloxy）propyl trimethoxysilane （MPS）-modified silica core, which was prepared by the Stober hydrolysis as the first stage reaction. The tri-layer hybrid microspheres were synthesized by the third-stage distillation precipitation copolymerization of functional MAA monomer and divinylbenzene （DVB） crosslinker in presence of silica/PMAA particles as seeds, in which the efficient hydrogen-bonding interaction between the carboxylic acid groups played as a driving force for the construction of monodisperse hybrid microspheres with tri-layer structure. The morphology and the structure of silica core, silica/PMAA core-shell particles, the tri-layer hybrid microspheres and the corresponding hollow polymer microspheres with movable silica cores were characterized by transmission electron microscopy （TEM）, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy （XPS）.展开更多
The corrosion behavior of environmental barrier coatings(EBCs)directly affects the service life and stability of ceramic matrix composite(CMC)structural parts in the aero-engines.The silicon carbide(SiC)whisker toughe...The corrosion behavior of environmental barrier coatings(EBCs)directly affects the service life and stability of ceramic matrix composite(CMC)structural parts in the aero-engines.The silicon carbide(SiC)whisker toughening phase and c-AlPO_(4) bonding phase are firstly used to improve the service life of novel tri-layer Yb_(2)Si_(2)O_(7)/mullite/SiC EBCs in the burner rig test.The formation of penetrating cracks in Yb_(2)Si_(2)O_(7)/mullite/SiC coating caused the failure of coating at 1673 K.The SiC whiskers in mullite middle coating significantly inhibited the formation of penetrating cracks in Yb_(2)Si_(2)O_(7)/mullite/SiC coating,and efficiently prevented the oxidation of carbon fiber reinforced silicon carbide(C_(f)/SiC)samples for 360-min thermal cycles(24 times)with a weight loss of 6.19×10^(−3) g·cm^(−2).Although c-AlPO_(4) particles further improved the service life of SiC_(w)-mullite(SM)coating,the overflow of PO_(x) gas aggravated the formation and expansion of cracks in the Yb_(2)Si_(2)O_(7) outer coating,and caused the service life of overall Yb_(2)Si_(2)O_(7)/c-AlPO_(4)-SiC_(w)-mullite(ASM)/SiC coating to be slightly lower than that of Yb_(2)Si_(2)O_(7)/SM/SiC coating.This study guides the design of modified tri-layer EBCs with long service life in high-temperature and high-speed gas environment.展开更多
The paper presents a new study on a tri-layer thin plate.Shadow moiré implemented with an advanced phase unwrapping technique is employed to obtain actual flexural deformation of a real-life plate sample subjecte...The paper presents a new study on a tri-layer thin plate.Shadow moiré implemented with an advanced phase unwrapping technique is employed to obtain actual flexural deformation of a real-life plate sample subjected to thermal loads.An analytical model is re-formulated to provide the plate with global closed-form solutions of the plate deflection as well as the interfacial stress and strain.With the measurements and the solutions available,an inverse iterative approach is developed to evaluate and maximize the correlation between the measured and the predicted thermal flexure,leading to ascertained materials' constitutive and thermal behaviour.The inverse search algorithm starts with estimated ranges of material property parameters and progressively updates them to finally approach the respective true values.The established model solutions along with the optimized material properties matrix enable an accurate evaluation of the interfacial stresses/strains for the specific plate sample.展开更多
随着计算机及网络技术的飞速发展,企业为了提高效率、规范日常管理构建信息系统已成必然.以疗养院系统为背景,介绍了基于Web的B/S与基于分布式结构的三层C/S混合模式的管理信息系统(MIS)设计与实现方案,并从功能结构、体系结构及安全性...随着计算机及网络技术的飞速发展,企业为了提高效率、规范日常管理构建信息系统已成必然.以疗养院系统为背景,介绍了基于Web的B/S与基于分布式结构的三层C/S混合模式的管理信息系统(MIS)设计与实现方案,并从功能结构、体系结构及安全性等方面对系统进行了论述.系统采用SQL Server 2000作为后台数据库管理系统,采用PB 8.0结合HTML语言及ASP等技术实现前台界面的开发.完成的疗养院管理信息系统具有实用价值.展开更多
文摘The problem with earth constructions is their low resistance to water. Step by step, the water degrades the exterior facings of the structures and ends up creating zones of weakness through the structures, making them collapse and creating enormous socio-economic problems, especially in rural areas. The solutions proposed to date, like the use of straw, cow dung, boiled skins, banana leaves, tar, cement soil, have shown their limits. Generally, the poor adhesion between the protected material and the protective layer means that the latter always ends up peeling off. This work, which is inspired by the traditional practice where plant tannins are used to brush the earthen walls to waterproof them, proposes a tri-layer coating composed of soil, powder and hydrolysable tannins extracted from the stem bark of Bridelia. This work focuses on the geotechnical characterization of the soil, the extraction of hydrolysable tannin, the manufacture of the micro-coating, the resistance tests carried out on the micro-coating, the technique of implementation and the test of evaluation of the performance of the tri-layer coating. The results obtained show that not only does the tri-layer coating adhere perfectly to the layer to protect, but it also waterproofs it and protects it against shocks.
文摘One purpose of this study was to develop a paliperidone(PAL)tri-layer ascending release pushepull osmotic pump(TA-PPOP)tablet which could meet the needs of clinical applications.And another purpose was to investigate whether different coating materials influenced in vivo performance of TA-PPOP.The ascending release mechanism of this trilayer delivery system on theory was elaborated.TA-PPOP was prepared by means of coating with cellulose acetate(CA)or ethyl cellulose(EC).Several important influence factors such as different core tablet compositions and different coating solution ingredients involved in the formulation procedure were investigated.The optimization of formulation and process was conducted by comparing different in vitro release behaviors of PAL.In vitro dissolution studies indicated that both the two formulations of different coating materials were able to deliver PAL at an ascending release rate during the whole 24 h test.The in vivo pharmacokinetics study showed that both self-made PPOP tablets with different coating had a good in vitro-in vivo correlation(IVIVC)and were bioequivalent with the brand product,which demonstrated no significant influence of the coating materials on the in vivo release acceleration of TA-PPOP.
基金National Science Council of Taiwan-China! grant number NSC8&0208-M007-083PC.
文摘The Fe_3O_4/Fe/Fe_3O_4 (MIM) tri-layer films (200 nm/12-93 nm/200 um) were prepared on Si(100) by DC-magnetron reactive-sputtering followed by air- or vacuum-annealing at 280-400℃ for 1.5 h, respectively. Magnetic properties and phases under different sandwich and annealing conditions were studied. In MIM structure, the incorporation of the interlayer iron does increase the magnetization measured under 8 kOe (M_8K), but reduce coercivity (H_c). The H_c of asdeposited films decreases from 354 Oe to 74 Oe; while M_8K increases from 254 to 392 emu/cc. By annealing in air, the whole MIM tri-layer film becomes γ-F_e2O_3, H_c is about 550 O_e and M_8K is around 250 emu/cc. The coercivity mechanism of as-deposited and annealed MIM trilayer films belongs to domain-wall pinning type. δM plots show that when the interlayer Fe thickness is 12 um, the Fe and Fe_3O_4 layers are decoupled in the as-deposited and annealed states; while it is coupled in the as deposited state when the Fe thickness increases to 23 um. Vacuum annealing of the MIM films leads to increase in both coercivity and magnetization, and to enhance the exchange coupling between layers.
基金This work was supported by the Doctoral Training Foundation of the National Education Commission.
文摘Sensitive magnetic field sensor with good performances can be fabricated utilizing the giant magneto-impedance (GMI) effect of soft magnetic multi-layer thin films. The transverse and longitudinal GMI effect in patterned FeSiB/Cu/FeSiB tri-layer films with the change of external magnetic field and frequency were studied at the same time. The change of the impedance of the films with the external magnetic fieldand frequency was shown. Comparing the longitudinal and transverse effect, the transverse effect has a larger linear range from zero magnetic field to a quite large magnetic field at all frequencies, and the change still were not saturated until the external magnetic field reached 1.2×104A/m, which illustrated that the films can be utilized to detect larger magnetic fields than now presented GMI sensors.
基金supported by the National Natural Science Foundation of China(No.20874049).
文摘Hollow poly（divinylbenzene-co-methacrylic acid） （P（DVB-co-MAA）） microspheres were prepared by the selective dissolution of the non-crosslinked poly（methacrylic acid） （PMAA） mid-layer in ethanol from the corresponding silica/PMAA/P（DVB-co-MAA） tri-layer hybrid microspheres, which were afforded by a three-stage reaction. Silica/PMAA core-shell hybrid microspheres were prepared by the second-stage distillation polymerization of methacrylic acid （MAA） via the capture of the oligomers and monomers with the aid of the vinyl groups on the surface of 3-（methacryloxy）propyl trimethoxysilane （MPS）-modified silica core, which was prepared by the Stober hydrolysis as the first stage reaction. The tri-layer hybrid microspheres were synthesized by the third-stage distillation precipitation copolymerization of functional MAA monomer and divinylbenzene （DVB） crosslinker in presence of silica/PMAA particles as seeds, in which the efficient hydrogen-bonding interaction between the carboxylic acid groups played as a driving force for the construction of monodisperse hybrid microspheres with tri-layer structure. The morphology and the structure of silica core, silica/PMAA core-shell particles, the tri-layer hybrid microspheres and the corresponding hollow polymer microspheres with movable silica cores were characterized by transmission electron microscopy （TEM）, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy （XPS）.
基金funded by the National Key R&D Program of China(Grant Nos.2021YFB3703800 and 2021YFB3703802)National Natural Science Foundation of China(Grant No.52102122)+1 种基金National Key Laboratory of Science and Technology on High-strength Structural Materials,Central South University(Grant No.SYSJJ2021LWS01)China Postdoctoral Science Foundation(Grant No.2022M711540).
文摘The corrosion behavior of environmental barrier coatings(EBCs)directly affects the service life and stability of ceramic matrix composite(CMC)structural parts in the aero-engines.The silicon carbide(SiC)whisker toughening phase and c-AlPO_(4) bonding phase are firstly used to improve the service life of novel tri-layer Yb_(2)Si_(2)O_(7)/mullite/SiC EBCs in the burner rig test.The formation of penetrating cracks in Yb_(2)Si_(2)O_(7)/mullite/SiC coating caused the failure of coating at 1673 K.The SiC whiskers in mullite middle coating significantly inhibited the formation of penetrating cracks in Yb_(2)Si_(2)O_(7)/mullite/SiC coating,and efficiently prevented the oxidation of carbon fiber reinforced silicon carbide(C_(f)/SiC)samples for 360-min thermal cycles(24 times)with a weight loss of 6.19×10^(−3) g·cm^(−2).Although c-AlPO_(4) particles further improved the service life of SiC_(w)-mullite(SM)coating,the overflow of PO_(x) gas aggravated the formation and expansion of cracks in the Yb_(2)Si_(2)O_(7) outer coating,and caused the service life of overall Yb_(2)Si_(2)O_(7)/c-AlPO_(4)-SiC_(w)-mullite(ASM)/SiC coating to be slightly lower than that of Yb_(2)Si_(2)O_(7)/SM/SiC coating.This study guides the design of modified tri-layer EBCs with long service life in high-temperature and high-speed gas environment.
基金The financial supports to this study by NSERC and OCE are acknowledged
文摘The paper presents a new study on a tri-layer thin plate.Shadow moiré implemented with an advanced phase unwrapping technique is employed to obtain actual flexural deformation of a real-life plate sample subjected to thermal loads.An analytical model is re-formulated to provide the plate with global closed-form solutions of the plate deflection as well as the interfacial stress and strain.With the measurements and the solutions available,an inverse iterative approach is developed to evaluate and maximize the correlation between the measured and the predicted thermal flexure,leading to ascertained materials' constitutive and thermal behaviour.The inverse search algorithm starts with estimated ranges of material property parameters and progressively updates them to finally approach the respective true values.The established model solutions along with the optimized material properties matrix enable an accurate evaluation of the interfacial stresses/strains for the specific plate sample.
文摘随着计算机及网络技术的飞速发展,企业为了提高效率、规范日常管理构建信息系统已成必然.以疗养院系统为背景,介绍了基于Web的B/S与基于分布式结构的三层C/S混合模式的管理信息系统(MIS)设计与实现方案,并从功能结构、体系结构及安全性等方面对系统进行了论述.系统采用SQL Server 2000作为后台数据库管理系统,采用PB 8.0结合HTML语言及ASP等技术实现前台界面的开发.完成的疗养院管理信息系统具有实用价值.
