Search2006 Vol. 13, No. 3
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2006, vol. 13, no. 3, pp.
193-198.
https://doi.org/10.1016/S1005-8850(06)60042-X
Abstract:
On the basis of the theories of mechanics of explosive and rock fracture mechanics, the mechanism of crack initiation and its expansion of directional fracture controlled blasting with shaped charges in rock were studied, then the blasting parameters were designed and tested by a model test in laboratory and field experiment. The experimental and test results showed that the energy from blasting is directionally concentrated for the cumulative action. The directional expansion of cracks is satisfactory, the results of the model test and field test suggested that the orientation fracture blasting with shaped charge is a good means of excavating tunnels or cutting rock.
On the basis of the theories of mechanics of explosive and rock fracture mechanics, the mechanism of crack initiation and its expansion of directional fracture controlled blasting with shaped charges in rock were studied, then the blasting parameters were designed and tested by a model test in laboratory and field experiment. The experimental and test results showed that the energy from blasting is directionally concentrated for the cumulative action. The directional expansion of cracks is satisfactory, the results of the model test and field test suggested that the orientation fracture blasting with shaped charge is a good means of excavating tunnels or cutting rock.
2006, vol. 13, no. 3, pp.
199-206.
https://doi.org/10.1016/S1005-8850(06)60043-1
Abstract:
The transmission ratio along the radian direction normal to the joints was studied in the Universal Distinct Element Code (UDEC). The variation of the transmission ratio with the ratio of joint spacing to wavelength was generalized into a general curve, which was determined by two critical points. The relationship between the two critical points and the affecting factors, quantity of joints and the normalized normal stiffness of joints, were obtained. A prediction model of the transmission ratio in the radian direction normal to the joints was proposed. The proposed model was applied to a field explosion test. The estimated values of the peak particle velocity from the prediction model were compared with the field records. The comparisons showed that the prediction model of the transmission ratio in the direction normal to the joints in the process of 2-D compressional wave propagation through multiple parallel joints is reliable.
The transmission ratio along the radian direction normal to the joints was studied in the Universal Distinct Element Code (UDEC). The variation of the transmission ratio with the ratio of joint spacing to wavelength was generalized into a general curve, which was determined by two critical points. The relationship between the two critical points and the affecting factors, quantity of joints and the normalized normal stiffness of joints, were obtained. A prediction model of the transmission ratio in the radian direction normal to the joints was proposed. The proposed model was applied to a field explosion test. The estimated values of the peak particle velocity from the prediction model were compared with the field records. The comparisons showed that the prediction model of the transmission ratio in the direction normal to the joints in the process of 2-D compressional wave propagation through multiple parallel joints is reliable.
2006, vol. 13, no. 3, pp.
207-212.
https://doi.org/10.1016/S1005-8850(06)60044-3
Abstract:
To solve the technical cruxes of the conventional system in deep rock mass, an automatic testing system for hydraulic fracturing that includes a single tube for hydraulic loop, a pressure-relief valve, central-tubeless packers, and a multichannel real-time data acquisition system was used for in-situ stresses measurement at great depths (over 1000 m) in a coalfield in Juye of Northern China. The values and orientations of horizontal principal stresses were determined by the new system. The virgin stress field and its distributing law were decided by the linear regression from the logged 37 points in seven boreholes. Besides, the typical boreholes arranged in both the adjacent zone and far away zone of the faults were analyzed, respectively. The results show that a stress concentration phenomenon and a deflection in the orientation of the maximal horizontal stress exist in the adjacent zone of the faults, which further provides theoretical basis for design and optimization of mining.
To solve the technical cruxes of the conventional system in deep rock mass, an automatic testing system for hydraulic fracturing that includes a single tube for hydraulic loop, a pressure-relief valve, central-tubeless packers, and a multichannel real-time data acquisition system was used for in-situ stresses measurement at great depths (over 1000 m) in a coalfield in Juye of Northern China. The values and orientations of horizontal principal stresses were determined by the new system. The virgin stress field and its distributing law were decided by the linear regression from the logged 37 points in seven boreholes. Besides, the typical boreholes arranged in both the adjacent zone and far away zone of the faults were analyzed, respectively. The results show that a stress concentration phenomenon and a deflection in the orientation of the maximal horizontal stress exist in the adjacent zone of the faults, which further provides theoretical basis for design and optimization of mining.
2006, vol. 13, no. 3, pp.
213-217.
https://doi.org/10.1016/S1005-8850(06)60045-5
Abstract:
The sulphide capacity of CaO-SiO2-Al2O3-MgO-FetO slags was studied at 1773 K using gas-slag equilibrium techniques. Utilizing a Pt crucible, the slag was equilibrated with a mixture of gases, namely, CO, CO2, SO2 and N2 to provide the partial pressure of oxygen and sulphur. It was shown that at fixed FetO and Al2O3 contents and a fixed {(%CaO)+(%MgO)}/(%SiO2) ratio, the sulphide capacity decreases with increasing MgO content. At a constant (%CaO)/(%SiO2) ratio and constant MgO and Al2O3 contents, increasing the FetO content of the slags also results in an increase of the sulphide capacity. The rising basicity of (%CaO)/(%SiO2) from 1.0 to 1.4 at fixed MgO, FetO and Al2O3 contents significantly increases the sulphide capacity.
The sulphide capacity of CaO-SiO2-Al2O3-MgO-FetO slags was studied at 1773 K using gas-slag equilibrium techniques. Utilizing a Pt crucible, the slag was equilibrated with a mixture of gases, namely, CO, CO2, SO2 and N2 to provide the partial pressure of oxygen and sulphur. It was shown that at fixed FetO and Al2O3 contents and a fixed {(%CaO)+(%MgO)}/(%SiO2) ratio, the sulphide capacity decreases with increasing MgO content. At a constant (%CaO)/(%SiO2) ratio and constant MgO and Al2O3 contents, increasing the FetO content of the slags also results in an increase of the sulphide capacity. The rising basicity of (%CaO)/(%SiO2) from 1.0 to 1.4 at fixed MgO, FetO and Al2O3 contents significantly increases the sulphide capacity.
2006, vol. 13, no. 3, pp.
218-221.
https://doi.org/10.1016/S1005-8850(06)60046-7
Abstract:
The overall decarburization mechanism can be divided into the decarburization in bulk molten steel and floating of CO against static pressure, the decarburization on the surface of argon bubbles and splashing particles. On the basis of each conception the RH-MFB decarburization mathematical model has been built according to the thermodynamic and mass conservation principle, and contributions of every decarburization mechanism were discussed and analyzed.
The overall decarburization mechanism can be divided into the decarburization in bulk molten steel and floating of CO against static pressure, the decarburization on the surface of argon bubbles and splashing particles. On the basis of each conception the RH-MFB decarburization mathematical model has been built according to the thermodynamic and mass conservation principle, and contributions of every decarburization mechanism were discussed and analyzed.
2006, vol. 13, no. 3, pp.
222-225.
https://doi.org/10.1016/S1005-8850(06)60047-9
Abstract:
On the basis of the Langevin equation and the Fokker-Planck equation, a stochastic model of bubble distribution in a gas-solid fluidized bed was developed. A fluidized bed with a cross section of 0.3 m×0.02 m and a height of 0.8 m was used to investigate the bubble distribution with the photographic method. Two distributors were used with orifice diameters of 3 and 6 mm and opening ratios of 6.4% and 6.8%, respectively. The particles were color glass beads with diameters of 0.3, 0.5 and 0.8 mm (Geldart group B particles). The model predictions are reasonable in accordance with the experiment data. The research results indicated that the distribution of bubble concentration was affected by the particle diameter, the fluidizing velocity, and the distributor style. The fluctuation extension of the distribution of bubble concentration narrowed as the particle diameter, fluidizing velocity and opening ratio of the distributor increased. For a given distributor and given particles the distribution was relatively steady along the bed height as the fluidizing velocity changed.
On the basis of the Langevin equation and the Fokker-Planck equation, a stochastic model of bubble distribution in a gas-solid fluidized bed was developed. A fluidized bed with a cross section of 0.3 m×0.02 m and a height of 0.8 m was used to investigate the bubble distribution with the photographic method. Two distributors were used with orifice diameters of 3 and 6 mm and opening ratios of 6.4% and 6.8%, respectively. The particles were color glass beads with diameters of 0.3, 0.5 and 0.8 mm (Geldart group B particles). The model predictions are reasonable in accordance with the experiment data. The research results indicated that the distribution of bubble concentration was affected by the particle diameter, the fluidizing velocity, and the distributor style. The fluctuation extension of the distribution of bubble concentration narrowed as the particle diameter, fluidizing velocity and opening ratio of the distributor increased. For a given distributor and given particles the distribution was relatively steady along the bed height as the fluidizing velocity changed.
2006, vol. 13, no. 3, pp.
226-229.
https://doi.org/10.1016/S1005-8850(06)60048-0
Abstract:
An efficient analytical decomposition technique was presented for solving the singular nonlinear boundary value problem arising in viscous flow when the Crocco variable was introduced. The approximate analytical solution may be represented in terms of a rapid convergent power series with elegantly computable terms. The reliability and efficiency of the approximate solutions were verified by numerical ones in the literature. The approximate analytical solutions can be successfully applied to give the values of skin friction coefficient.
An efficient analytical decomposition technique was presented for solving the singular nonlinear boundary value problem arising in viscous flow when the Crocco variable was introduced. The approximate analytical solution may be represented in terms of a rapid convergent power series with elegantly computable terms. The reliability and efficiency of the approximate solutions were verified by numerical ones in the literature. The approximate analytical solutions can be successfully applied to give the values of skin friction coefficient.
2006, vol. 13, no. 3, pp.
230-234.
https://doi.org/10.1016/S1005-8850(06)60049-2
Abstract:
Large quantity of fine Ti(C,N) particles, 15-30 nm in size, were observed in low carbon hot strips added to a small amount of Ti and produced by CSP process. The results showed that the precipitation of Ti(C,N) mostly took place during soaking and hot rolling, which is significantly different from that in the conventional production. These fine Ti carbonitride particles could be very effective on the austenite grain refinement by hindering grain growth of recrystallized austenite. Their precipitation behavior was discussed and compared with that of the steels produced in the conventional production.
Large quantity of fine Ti(C,N) particles, 15-30 nm in size, were observed in low carbon hot strips added to a small amount of Ti and produced by CSP process. The results showed that the precipitation of Ti(C,N) mostly took place during soaking and hot rolling, which is significantly different from that in the conventional production. These fine Ti carbonitride particles could be very effective on the austenite grain refinement by hindering grain growth of recrystallized austenite. Their precipitation behavior was discussed and compared with that of the steels produced in the conventional production.
Relationship of microstructure transformation and hardening behavior of type 17-4 PH stainless steel
2006, vol. 13, no. 3, pp.
235-239.
https://doi.org/10.1016/S1005-8850(06)60050-9
Abstract:
The relationship between the microstructure transformation of type 17-4 PH stainless steel and the aging hardening behavior was investigated. The results showed that, when 17-4 PH stainless steel aging at 595°C, the bulk hardness of samples attains its peak value (42.5 HRC) for about 20 min, and then decreases at all time. TEM revealed the microstructure corresponding with peak hardness is that the fine spheroid-shape copper with the fcc crystal structure and the fiber-shape secondary carbide M23C6 precipitated from the lath martensite matrix. Both precipitations of copper and M23C6 are the reasons for strengthening of the alloy at this temperature. With the extension of holding time at this temperature, the copper and secondary carbide grow and lose the coherent relationship with the matrix, so the bulk hardness of samples decreases.
The relationship between the microstructure transformation of type 17-4 PH stainless steel and the aging hardening behavior was investigated. The results showed that, when 17-4 PH stainless steel aging at 595°C, the bulk hardness of samples attains its peak value (42.5 HRC) for about 20 min, and then decreases at all time. TEM revealed the microstructure corresponding with peak hardness is that the fine spheroid-shape copper with the fcc crystal structure and the fiber-shape secondary carbide M23C6 precipitated from the lath martensite matrix. Both precipitations of copper and M23C6 are the reasons for strengthening of the alloy at this temperature. With the extension of holding time at this temperature, the copper and secondary carbide grow and lose the coherent relationship with the matrix, so the bulk hardness of samples decreases.
2006, vol. 13, no. 3, pp.
240-243.
https://doi.org/10.1016/S1005-8850(06)60051-0
Abstract:
An optimization strategy for high speed machining of hardened die/mold steel based on machining feature analysis was studied. It is a further extension of the previously presented study on the thermal mechanism of end milling and constant cutting force control. An objective function concerning machining cost and associated optimization algorithm based on machining time and cutting length calculation was proposed. Constraints to satisfy specific machining strategies when high speed machining the hardened die/mold steel, trochoid tool path pattern in slot end milling to avoid over-heat and feed rate adaptation to avoid over-load, were also discussed. As a case study, the tool selection problem when machining a die part with multiple machining features was investigated.
An optimization strategy for high speed machining of hardened die/mold steel based on machining feature analysis was studied. It is a further extension of the previously presented study on the thermal mechanism of end milling and constant cutting force control. An objective function concerning machining cost and associated optimization algorithm based on machining time and cutting length calculation was proposed. Constraints to satisfy specific machining strategies when high speed machining the hardened die/mold steel, trochoid tool path pattern in slot end milling to avoid over-heat and feed rate adaptation to avoid over-load, were also discussed. As a case study, the tool selection problem when machining a die part with multiple machining features was investigated.
2006, vol. 13, no. 3, pp.
244-249.
https://doi.org/10.1016/S1005-8850(06)60052-2
Abstract:
The low-cycle fatigue behavior of powder metallurgy Rene95 alloy containing surface inclusions was investigated by in-situ observation with scanning electron microscopy (SEM). The process of fatigue crack initiation and early stage of propagation behavior indicates that fatigue crack mainly occurs at the interface between the inclusion and the matrix. The effect of inclusion on the fatigue crack initiation and the early stage of crack growth was very obvious. The fatigue crack growth path in the matrix is similar to the shape of inclusion made on the basis of fatigue fracture image analysis. The empiric relation between the surface and inside crack growth length, near a surface inclusion, can be expressed. Therefore, the fatigue crack growth rate or life of P/M Rene95 alloy including the inclusions can be evaluated on the basis of the measurable surface crack length parameter. In addition, the effect of two inclusions on the fatigue crack initiation behavior was investigated by the in-situ observation with SEM.
The low-cycle fatigue behavior of powder metallurgy Rene95 alloy containing surface inclusions was investigated by in-situ observation with scanning electron microscopy (SEM). The process of fatigue crack initiation and early stage of propagation behavior indicates that fatigue crack mainly occurs at the interface between the inclusion and the matrix. The effect of inclusion on the fatigue crack initiation and the early stage of crack growth was very obvious. The fatigue crack growth path in the matrix is similar to the shape of inclusion made on the basis of fatigue fracture image analysis. The empiric relation between the surface and inside crack growth length, near a surface inclusion, can be expressed. Therefore, the fatigue crack growth rate or life of P/M Rene95 alloy including the inclusions can be evaluated on the basis of the measurable surface crack length parameter. In addition, the effect of two inclusions on the fatigue crack initiation behavior was investigated by the in-situ observation with SEM.
2006, vol. 13, no. 3, pp.
250-255.
https://doi.org/10.1016/S1005-8850(06)60053-4
Abstract:
The preparation of fine copper powders by chemical reduction method was investigated. The reaction of [Cu(NH3)4]2+ complex with hydrazine hydrate gives spherical monodispersed fine copper powders. The spherical copper powder with a uniform size of 3.5 ± 0.5 μm was processed to obtain flake copper powder having a uniform size of 8-10 μm, excellent dispersibility and uniform shape. The spherical copper powder of 2.5 ± 0.3 μm in size, flake copper, glass frit and vehicle were mixed to prepare copper paste, which was fired in 910-920°C to obtain BME-MLCC (base metal multilayer ceramic capacitor) with a dense surface of end termination, high adhesion and qualified electrical behavior. Polarized light photo and SEM were employed to observe the copper end termination of BME-MLCC. The rough interface from the interfacial reaction between glass and chip gives high adhesion.
The preparation of fine copper powders by chemical reduction method was investigated. The reaction of [Cu(NH3)4]2+ complex with hydrazine hydrate gives spherical monodispersed fine copper powders. The spherical copper powder with a uniform size of 3.5 ± 0.5 μm was processed to obtain flake copper powder having a uniform size of 8-10 μm, excellent dispersibility and uniform shape. The spherical copper powder of 2.5 ± 0.3 μm in size, flake copper, glass frit and vehicle were mixed to prepare copper paste, which was fired in 910-920°C to obtain BME-MLCC (base metal multilayer ceramic capacitor) with a dense surface of end termination, high adhesion and qualified electrical behavior. Polarized light photo and SEM were employed to observe the copper end termination of BME-MLCC. The rough interface from the interfacial reaction between glass and chip gives high adhesion.
2006, vol. 13, no. 3, pp.
256-262.
https://doi.org/10.1016/S1005-8850(06)60054-6
Abstract:
The influences of interphase on dynamic effective properties of composites reinforced by randomly dispersed spherical par ticles were studied. A thin homogeneous elastic interphase with different shear and bulk moduli, located between the reinforced particle and the host matrix, was introduced to model the interfacial bonding state. The effects of such an interphase on the coherent plane waves were studied numerically. Numerical simulations were carried out for SiC-Al composites with four typical cases of interphase. It was found that the property of interphase has significant influences on the effective propagation constants of coherent waves and the dynamic effective elastic moduli of the composites. The influences on the coherent longitudinal wave and the coherent shear waves were different and dependent upon the frequency range. Moreover, several imperfect interface models, i.e., the spring model, mass model, and spring-mass model, were studied numerically and compared with the interphase model. It was found that the spring model is a more suitable model than the mass model for the light and weak interphase whereas the mass model is a more suitable model than the spring model for the heavy and strong interphase.
The influences of interphase on dynamic effective properties of composites reinforced by randomly dispersed spherical par ticles were studied. A thin homogeneous elastic interphase with different shear and bulk moduli, located between the reinforced particle and the host matrix, was introduced to model the interfacial bonding state. The effects of such an interphase on the coherent plane waves were studied numerically. Numerical simulations were carried out for SiC-Al composites with four typical cases of interphase. It was found that the property of interphase has significant influences on the effective propagation constants of coherent waves and the dynamic effective elastic moduli of the composites. The influences on the coherent longitudinal wave and the coherent shear waves were different and dependent upon the frequency range. Moreover, several imperfect interface models, i.e., the spring model, mass model, and spring-mass model, were studied numerically and compared with the interphase model. It was found that the spring model is a more suitable model than the mass model for the light and weak interphase whereas the mass model is a more suitable model than the spring model for the heavy and strong interphase.
2006, vol. 13, no. 3, pp.
263-266.
https://doi.org/10.1016/S1005-8850(06)60055-8
Abstract:
New aluminum matrix composites strengthened by Al2O3 particulates through stirring cast by adding NH4Al(SO4)2 to the molten aluminum have been fabricated. TEM observation shows that in-situ Al2O3 particulates are generally spherical and they are uniformly distributed in the Al matrix. Dry sliding wear test results show that the volume loss of the unreinforced Al matrix is about three times that of the Al2O3 reinforced metal matrix composite (MMC) and the volume loss of the MMC fabricated by adding Al2O3 is larger than that of the MMC by adding NH4Al(SO4)2. Lubricating sliding wear test results show that the volume loss of the MMCs increases more slowly than that of the matrix with the increasing of the load.
New aluminum matrix composites strengthened by Al2O3 particulates through stirring cast by adding NH4Al(SO4)2 to the molten aluminum have been fabricated. TEM observation shows that in-situ Al2O3 particulates are generally spherical and they are uniformly distributed in the Al matrix. Dry sliding wear test results show that the volume loss of the unreinforced Al matrix is about three times that of the Al2O3 reinforced metal matrix composite (MMC) and the volume loss of the MMC fabricated by adding Al2O3 is larger than that of the MMC by adding NH4Al(SO4)2. Lubricating sliding wear test results show that the volume loss of the MMCs increases more slowly than that of the matrix with the increasing of the load.
2006, vol. 13, no. 3, pp.
267-271.
https://doi.org/10.1016/S1005-8850(06)60056-X
Abstract:
SiCp/2014Al composites were bonded with the vacuum diffusion welding technique using Ni as the interlayer metal. Ni and Al were interdiffused and there were intermetallic compounds formed in the inter transition layer, which was composed of Ni3Al//NiAl//NiAl3. The relation between the diffusion distance and the element concentration was calculated according to Fick’s second law. The relations of the diffusion concentration and the diffusion welding technique parameters were calculated.
SiCp/2014Al composites were bonded with the vacuum diffusion welding technique using Ni as the interlayer metal. Ni and Al were interdiffused and there were intermetallic compounds formed in the inter transition layer, which was composed of Ni3Al//NiAl//NiAl3. The relation between the diffusion distance and the element concentration was calculated according to Fick’s second law. The relations of the diffusion concentration and the diffusion welding technique parameters were calculated.
2006, vol. 13, no. 3, pp.
272-276.
https://doi.org/10.1016/S1005-8850(06)60057-1
Abstract:
Thin films of silicon carbide nitride (SiCN) were prepared on (111) oriented silicon substrates by pulsed high-energy density plasma (PHEDP). The evolution of the chemical bonding states between silicon, nitrogen and carbon was investigated as a function of discharge voltage using X-ray photoelectron spectroscopy. With an increase in discharge voltage both the C 1s and N 1s spectra shift to lower binding energy due to the formation of C-Si and N-Si bonds. The Si-C-N bonds were observed in the deconvolved C 1s and N 1s spectra. The X-ray diffractometer (XRD) results show that there were no crystals in the films. The thickness of the films was approximately 1-2 μm with scanning electron microscopy (SEM).
Thin films of silicon carbide nitride (SiCN) were prepared on (111) oriented silicon substrates by pulsed high-energy density plasma (PHEDP). The evolution of the chemical bonding states between silicon, nitrogen and carbon was investigated as a function of discharge voltage using X-ray photoelectron spectroscopy. With an increase in discharge voltage both the C 1s and N 1s spectra shift to lower binding energy due to the formation of C-Si and N-Si bonds. The Si-C-N bonds were observed in the deconvolved C 1s and N 1s spectra. The X-ray diffractometer (XRD) results show that there were no crystals in the films. The thickness of the films was approximately 1-2 μm with scanning electron microscopy (SEM).
2006, vol. 13, no. 3, pp.
277-280.
https://doi.org/10.1016/S1005-8850(06)60058-3
Abstract:
Bi2-xSbxTe3 thermoelectric films were electrochemically deposited from the solution containing Bi3+, HTeO2+ and SbO+. ESEM (environmental scanning electron microscope) investigations indicated that the crystalline state of Bi2-xSbxTe3 films transformed from equiaxed crystal to dendritic crystal with the negative shift of deposition potential. XRD and EDS were used to characterize the structure and composition of the electrodeposited films. The Seebeck coefficient and the temperature dependence of the resistance of Bi2-xSbxTe3 films were measured. The results showed that the composition of the film electrodeposited at ?0.5 V is Bi0.5Sb1.5Te3 with the largest Seebeck coefficient of 213 μV·K-1.
Bi2-xSbxTe3 thermoelectric films were electrochemically deposited from the solution containing Bi3+, HTeO2+ and SbO+. ESEM (environmental scanning electron microscope) investigations indicated that the crystalline state of Bi2-xSbxTe3 films transformed from equiaxed crystal to dendritic crystal with the negative shift of deposition potential. XRD and EDS were used to characterize the structure and composition of the electrodeposited films. The Seebeck coefficient and the temperature dependence of the resistance of Bi2-xSbxTe3 films were measured. The results showed that the composition of the film electrodeposited at ?0.5 V is Bi0.5Sb1.5Te3 with the largest Seebeck coefficient of 213 μV·K-1.
2006, vol. 13, no. 3, pp.
281-286.
https://doi.org/10.1016/S1005-8850(06)60059-5
Abstract:
Montmorillonite/cationic azobenzene dye (GTL) intercalation compounds were prepared by the conventional ion exchange method. As compared with that of pure GTL, the thermal stability of the intercalated GTL was greatly enhanced, and the absorption band corresponding to azobenzene group in intercalated GTL shifted towards a longer wavelength by 55 nm, which could be ascribed to the strong conjugation of GTL supramolecular order structure (J cluster) confined in a nanoscale space of montmorillonite interlayer gallery. The microstructures of the resulting intercalation compounds could be successfully controlled by varying the amount of dye loaded as evidenced by the basal spacing of the intercalation compounds. The intercalated azo dye in the montmorillonite interlayer space exhibited reversible trans-to-cis photoisomerization and thermal cis-to-trans reaction. FTIR proved the successful intercalation of GTL into the silicate layer.
Montmorillonite/cationic azobenzene dye (GTL) intercalation compounds were prepared by the conventional ion exchange method. As compared with that of pure GTL, the thermal stability of the intercalated GTL was greatly enhanced, and the absorption band corresponding to azobenzene group in intercalated GTL shifted towards a longer wavelength by 55 nm, which could be ascribed to the strong conjugation of GTL supramolecular order structure (J cluster) confined in a nanoscale space of montmorillonite interlayer gallery. The microstructures of the resulting intercalation compounds could be successfully controlled by varying the amount of dye loaded as evidenced by the basal spacing of the intercalation compounds. The intercalated azo dye in the montmorillonite interlayer space exhibited reversible trans-to-cis photoisomerization and thermal cis-to-trans reaction. FTIR proved the successful intercalation of GTL into the silicate layer.
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