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Online since: November 2013
Authors: Jian Jiao, Hai Peng Qiu, Ming Wei Chen, Wei Gang Zhang, Ruo Gu Wang
The IR data is consistent with the IR standard spectrum of tetrahydrofuran.
MS data for the ZrC precursor: m/z=72 (tetrahydrofuran), m/z=58(acetone), m/z=44 (carbon dioxide).
FTIR (Fig. 1) and MS (Fig. 2) data: the wavelengths of 2360cm-1 (carbon dioxide), 3014cm-1 (methane), m/z=16(methane), m/z=44(carbon dioxide).
At relatively low reaction temperature, it could not provide enough activation energy for occurrence of carbothermal reduction.
When the temperature increased from 1000°C to 1200°C, carbothermal reduction occurred, and a little of the ZrO2 was reduced to ZrC.
MS data for the ZrC precursor: m/z=72 (tetrahydrofuran), m/z=58(acetone), m/z=44 (carbon dioxide).
FTIR (Fig. 1) and MS (Fig. 2) data: the wavelengths of 2360cm-1 (carbon dioxide), 3014cm-1 (methane), m/z=16(methane), m/z=44(carbon dioxide).
At relatively low reaction temperature, it could not provide enough activation energy for occurrence of carbothermal reduction.
When the temperature increased from 1000°C to 1200°C, carbothermal reduction occurred, and a little of the ZrO2 was reduced to ZrC.
Online since: July 2011
Authors: Kontan Tarigan, D. S. Yang, S. C. Yu
Structural data were obtained by using an X-ray diffractometer with the Cu-Kα radiation and Extended X-ray absorption fine structure (EXAFS).
Based on XRD data, the crystallite size and the lattice parameters of the samples were estimated by the Scherrer and Bragg equations of the Fe(110) peak.
EXAFS data were collected from the 3C1 EXAFS beam line of the Pohang Light Source (PLS).
After that, the EXAFS data were analyzed by making use of the IFEFFIT software.
Based on these XRD data, the crystallite size and the lattice parameter (a) can be evaluated from the Scherrer and Bragg equations, Figure 3.
Based on XRD data, the crystallite size and the lattice parameters of the samples were estimated by the Scherrer and Bragg equations of the Fe(110) peak.
EXAFS data were collected from the 3C1 EXAFS beam line of the Pohang Light Source (PLS).
After that, the EXAFS data were analyzed by making use of the IFEFFIT software.
Based on these XRD data, the crystallite size and the lattice parameter (a) can be evaluated from the Scherrer and Bragg equations, Figure 3.
Online since: June 2014
Authors: Yong Kang Xu, Zheng Jing Wan, Ji Lan Zhang, Jia Ju Wu
The relational mapping tabla has a large data size, and the data access to this table mainly positions the only data by two fields of TableName and OID, so these two fields are used to create the index.
Because the index of main memory database is created based on the plaintext data table and the index of relational mapping table is also created based on the plaintext, the plaintext index has solved other complicated ciphertext index problems in other database encryption schemes, and the failure in effective using or the performance reduction of index caused by the loss of original partial ordering relation among data due to the encryption will never occur. 3.2 Encryption and Decryption Synchronous Layer The data which need to be encrypted are plaintext data rows in the main memory database and ciphertext files in the relational database, so in order to keep the consistency to the application system of data in the two databases, the encryption and decryption synchronous layer is required to realize the data synchronization.
As for the data adding, the basic service of adding ciphertext file data will be called; as for the data deletion, the basic service of deleting ciphertext file data will be called; as for the data modification, the basic service of deleting ciphertext file data will be called firstly, and then the basic service of adding ciphertext file data will be called.
As for adding data, the basic service of adding ciphertext data will be called to increase the data in the relational mapping table and generate the files in the operating system; as for deleting data, the basic service of deleting ciphertext data will be called to delete the data in the relational mapping table and the files in the operating system; as for modifying data, the basic service of deleting ciphertext data will be firstly called to delete the data and files before modification, and then the basic service of adding ciphertext data will be called to generate the data and files after modification. 2) Ciphertext loaded to plaintext when starting: when the application system starts, this functional service can firstly decrypt all ciphertext data in the relational database and then load into the corresponding plaintext table in the main memory database.
Scheme Evaluation This scheme administrates the running state and storage state of data separately, and even the medium is stolen or lost, the running-state plaintext data administrated by the main memory database will be protected due to the data loss caused by the memory outage, and the storage-state ciphertext data administrated by the relational database will be protected due to the data encryption, so as to avoid the data leakage effectively.
Because the index of main memory database is created based on the plaintext data table and the index of relational mapping table is also created based on the plaintext, the plaintext index has solved other complicated ciphertext index problems in other database encryption schemes, and the failure in effective using or the performance reduction of index caused by the loss of original partial ordering relation among data due to the encryption will never occur. 3.2 Encryption and Decryption Synchronous Layer The data which need to be encrypted are plaintext data rows in the main memory database and ciphertext files in the relational database, so in order to keep the consistency to the application system of data in the two databases, the encryption and decryption synchronous layer is required to realize the data synchronization.
As for the data adding, the basic service of adding ciphertext file data will be called; as for the data deletion, the basic service of deleting ciphertext file data will be called; as for the data modification, the basic service of deleting ciphertext file data will be called firstly, and then the basic service of adding ciphertext file data will be called.
As for adding data, the basic service of adding ciphertext data will be called to increase the data in the relational mapping table and generate the files in the operating system; as for deleting data, the basic service of deleting ciphertext data will be called to delete the data in the relational mapping table and the files in the operating system; as for modifying data, the basic service of deleting ciphertext data will be firstly called to delete the data and files before modification, and then the basic service of adding ciphertext data will be called to generate the data and files after modification. 2) Ciphertext loaded to plaintext when starting: when the application system starts, this functional service can firstly decrypt all ciphertext data in the relational database and then load into the corresponding plaintext table in the main memory database.
Scheme Evaluation This scheme administrates the running state and storage state of data separately, and even the medium is stolen or lost, the running-state plaintext data administrated by the main memory database will be protected due to the data loss caused by the memory outage, and the storage-state ciphertext data administrated by the relational database will be protected due to the data encryption, so as to avoid the data leakage effectively.
Online since: January 2012
Authors: Zhan Huang, Feng Xing, Zhuo Ni, Xue Xiao Du, Shuai Wang
The pore size distribution and surface area of the cement composite with microcapsule are analyzed, showing a reduction in the pore content of cement composite and makes the pores smaller, which would improve durability and impermeability for designed materials.
The usage of microcapsules in the concrete composites leads to a recovery in the bending strength while a steady reduction in the properties for the cement materials, showing that the microcapsules can be effectively applied in the design of self-healing concrete composites.
It is observed that both the initial setting time and the final setting time show no change when these microcapsules were added into the cement, respectively being 2.8 hours and 3.6 hours, which are the same as the data for the cement.
The experimental data indicate that the usage of microcapsules in the concrete composites leads to a recovery in the bending strength while a steady reduction in these properties for the cement materials.
The data of pore size and surface area indicate that the application of microcapsule in cement composite can improve the durability and impermeability for concrete structure [8].
The usage of microcapsules in the concrete composites leads to a recovery in the bending strength while a steady reduction in the properties for the cement materials, showing that the microcapsules can be effectively applied in the design of self-healing concrete composites.
It is observed that both the initial setting time and the final setting time show no change when these microcapsules were added into the cement, respectively being 2.8 hours and 3.6 hours, which are the same as the data for the cement.
The experimental data indicate that the usage of microcapsules in the concrete composites leads to a recovery in the bending strength while a steady reduction in these properties for the cement materials.
The data of pore size and surface area indicate that the application of microcapsule in cement composite can improve the durability and impermeability for concrete structure [8].
Online since: November 2015
Authors: Xue Mei Ding, Li Zhu Chen, Lu Lu Xu
Textile printing and dyeing enterprises are the main governance object and they carried out a series of energy/water conversation and emission/pollution reduction projects and measures.
The textile printing and dyeing enterprises have carried out a series of energy and water conservation as well as emission reduction projects.
WF=BWF+GWF+WFcaused by energy or material (1) Where: WF means the water footprint; BWF means the blue water footprint; GWF means the grey water footprint; WF caused by energy or material means the indirect water footprint of energy or material used by the enterprise; BWF=Vwithdrawl-Veffluent (2) Where: Vwithdrawl means the volume of the water withdrawal by the enterprise; Veffluent means the volume of the effluent the enterprise discharges to the centralized sewage treatment plant; GWF=Veffluent×Ceffl-Vwithdrawl×CwithdrawlCmax-Cnat (3) Where: Ceffl means the pollutant concentration of the effluent, we use the testing data of COD concentration in the effluent in this paper; Cwithdrawl means the pollutant concentration of the water withdrawal, we use the testing data of COD concentration in the water withdrawal in this paper;
Cmax means the ambient water quality standard for the pollutant, we use the limit value of COD concentration for the industrial water in GB 3838-2002 The surface water environment quality standard: 30 mg/L; Cnat means the natural concentration in the receiving water body, we use the annual average testing data of COD concentration of the receiving water body in Yangtze River in 2014: 2 mg/L.
Therefore, WF and CF are effective tools to evaluate the environmental performance of the energy/water conversation and emission/pollution reduction project that the production enterprises conduct.
The textile printing and dyeing enterprises have carried out a series of energy and water conservation as well as emission reduction projects.
WF=BWF+GWF+WFcaused by energy or material (1) Where: WF means the water footprint; BWF means the blue water footprint; GWF means the grey water footprint; WF caused by energy or material means the indirect water footprint of energy or material used by the enterprise; BWF=Vwithdrawl-Veffluent (2) Where: Vwithdrawl means the volume of the water withdrawal by the enterprise; Veffluent means the volume of the effluent the enterprise discharges to the centralized sewage treatment plant; GWF=Veffluent×Ceffl-Vwithdrawl×CwithdrawlCmax-Cnat (3) Where: Ceffl means the pollutant concentration of the effluent, we use the testing data of COD concentration in the effluent in this paper; Cwithdrawl means the pollutant concentration of the water withdrawal, we use the testing data of COD concentration in the water withdrawal in this paper;
Cmax means the ambient water quality standard for the pollutant, we use the limit value of COD concentration for the industrial water in GB 3838-2002 The surface water environment quality standard: 30 mg/L; Cnat means the natural concentration in the receiving water body, we use the annual average testing data of COD concentration of the receiving water body in Yangtze River in 2014: 2 mg/L.
Therefore, WF and CF are effective tools to evaluate the environmental performance of the energy/water conversation and emission/pollution reduction project that the production enterprises conduct.
Online since: August 2011
Authors: Shou Wen Yao, Jian Li Lv, Qing Dong Peng
According to the result of optimization, the CAD model of housing is rebuilt and the finite element analysis of the new housing is done.The results show that both the static and dynamic performance are improved besides the mass reduction, namely, dynamic topology optimization can significantly improve the product’s performance.
The dynamic load data of all bearings is the force boundary of the analysis, which is the priority of the dynamic analysis.
The time load data is transferred to frequency data by Fast Fourier Transformation (FFT).
Fig 3 Elements density contour of housing’s dynamic topology optimization CAD Model redesign and verification The mass of the new housing is 314.5kg after redesign CAD model of the housing according to structural optimization with 18.4kg less than the old one, in which the mass reduction of wall thickness is 13.1kg, about 71.2% of the total mass reduction.
The dynamic load data of all bearings is the force boundary of the analysis, which is the priority of the dynamic analysis.
The time load data is transferred to frequency data by Fast Fourier Transformation (FFT).
Fig 3 Elements density contour of housing’s dynamic topology optimization CAD Model redesign and verification The mass of the new housing is 314.5kg after redesign CAD model of the housing according to structural optimization with 18.4kg less than the old one, in which the mass reduction of wall thickness is 13.1kg, about 71.2% of the total mass reduction.
Online since: January 2018
Authors: Wen Zhong Zhao, Yi Hang Yu, Jun Zhang
The results show that the thicknesses and elastic modulus have a significant effects on TL, TL are enhanced with the thicknesses increasing of the poroelastic materials layers, a 4.9dB addition of TL is achieved when thickness is added from 2cm to 3cm; TL are enhanced with the reduction of the elastic modulus in considered frequency range, and TL are reduced with the declining of viscous lengths and with the addition of the flow resistivity when the frequencies are higher than 600Hz.
HU Ying[10] has been set up a finite element model for calculating the acoustic transmission performance of double-wall sound packages with the poroelastic materials, the sound transmission loss is achieved, and the numerical results matched well with the measured data.
TL are calculated for three elastic modulus with 440000N/m2(initial), 44000 N/m2 and 4400 N/m2, respectively, the curves of TL versus the elastic modulus is shown in Fig.3, Fig.3 show that the TL are increasing with reduction of elastic modulus in lower frequency such as less than 550Hz, but when frequency is higher than 550Hz TL of elastic modulus 4400 is lower than ones of elastic modulus 440000(initial).
(1) The thicknesses have a significant effects on TL, TL can be enhanced with the thicknesses increasing of the poroelastic materials layers, especially, TL can obviously be added at the acoustic insulation trough, and the frequency of the first acoustic insulation trough can also be added; (2) The reduction of the elastic modulus of the poroelastic materials can result to the addition of TL in considered frequency range; when frequency is less than 550Hz, the lesser value of the elastic modulus can result to a more addition of TL; (3) The flow resistivity have a little effects on TL when the frequencies are less than 300Hz, generally, TL can be reduced with the increasing of the flow resistivity when the frequencies are higher than 600Hz; (4) The reduction of the viscous length can result to the reduction of TL when the frequencies are higher than 600Hz, and the viscous lengths has almost non-effect on TL when the frequencies are lower than 300Hz.
[7] Rumpler.R , Deü.J-F, Göransson.P, A modal-based reduction method for sound absorbing porous materials in poro-acoustic finite element models, The Journal of the Acoustic Society of America, 132(5), 3162–3179, (2012)
HU Ying[10] has been set up a finite element model for calculating the acoustic transmission performance of double-wall sound packages with the poroelastic materials, the sound transmission loss is achieved, and the numerical results matched well with the measured data.
TL are calculated for three elastic modulus with 440000N/m2(initial), 44000 N/m2 and 4400 N/m2, respectively, the curves of TL versus the elastic modulus is shown in Fig.3, Fig.3 show that the TL are increasing with reduction of elastic modulus in lower frequency such as less than 550Hz, but when frequency is higher than 550Hz TL of elastic modulus 4400 is lower than ones of elastic modulus 440000(initial).
(1) The thicknesses have a significant effects on TL, TL can be enhanced with the thicknesses increasing of the poroelastic materials layers, especially, TL can obviously be added at the acoustic insulation trough, and the frequency of the first acoustic insulation trough can also be added; (2) The reduction of the elastic modulus of the poroelastic materials can result to the addition of TL in considered frequency range; when frequency is less than 550Hz, the lesser value of the elastic modulus can result to a more addition of TL; (3) The flow resistivity have a little effects on TL when the frequencies are less than 300Hz, generally, TL can be reduced with the increasing of the flow resistivity when the frequencies are higher than 600Hz; (4) The reduction of the viscous length can result to the reduction of TL when the frequencies are higher than 600Hz, and the viscous lengths has almost non-effect on TL when the frequencies are lower than 300Hz.
[7] Rumpler.R , Deü.J-F, Göransson.P, A modal-based reduction method for sound absorbing porous materials in poro-acoustic finite element models, The Journal of the Acoustic Society of America, 132(5), 3162–3179, (2012)
Online since: February 2011
Authors: Mohammed Rafiq Abdul Kadir, Mat Uzir Wahit, Mazatusziha Ahmad, Khairul Zaman Mohd Dahlan
Incorporation of PEG shows a synergism effect on the reduction of blends viscosity.
Viscosity Reduction of UHMWPE/HDPE/PEG Blends.
The flexural strength was maintained up to 60wt% of HDPE, with further reduction in strength observed with increasing HDPE concentration.
The reduction in strength from 70 to 90 wt% HDPE is expected for blends with high fractions of HDPE.
In this work the specific surface area of HA is 33.05 m²/g (from particle size distribution data) and the particle size is 7.51 µm, with its irregular shape (Fig. 3c) showing encouraging result and is favorable to improve surface contact between the filler and matrix, thereby increasing the strength of the composites.
Viscosity Reduction of UHMWPE/HDPE/PEG Blends.
The flexural strength was maintained up to 60wt% of HDPE, with further reduction in strength observed with increasing HDPE concentration.
The reduction in strength from 70 to 90 wt% HDPE is expected for blends with high fractions of HDPE.
In this work the specific surface area of HA is 33.05 m²/g (from particle size distribution data) and the particle size is 7.51 µm, with its irregular shape (Fig. 3c) showing encouraging result and is favorable to improve surface contact between the filler and matrix, thereby increasing the strength of the composites.
Recrystallization Texture of Copper as a Function of Layer Thickness in Roll-Bonded Cu-Nb Composites
Online since: July 2007
Authors: S.C.V. Lim, Anthony D. Rollett
Necker et al. [5] showed for OFE Cu rolled to reductions of 73% and 90%, that the
strength of the Cube recrystallization texture component increases with increasing rolling reduction.
Methods Table 1 details the composites studied, their respective names, percentage reduction imposed and thicknesses of the Cu layers.
The orientation distribution function (ODF) for the Cu layers was calculated by the harmonic method from incomplete {111}Cu, {200}Cu, {220}Cu, and {311}Cu, pole figures using the Los Alamos Preferred Orientation Package (popLA) after correction of the data with respect to measured background and calculated defocusing error.
(a) (b) Figure 4: Misorientation distribution plots for composite sample reduced to a) 73% reduction and b) 92% reduction
(a) (b) Figure 5: Grain diameter distribution plots for composite sample reduced to a) 73% reduction and b) 92% reduction
Methods Table 1 details the composites studied, their respective names, percentage reduction imposed and thicknesses of the Cu layers.
The orientation distribution function (ODF) for the Cu layers was calculated by the harmonic method from incomplete {111}Cu, {200}Cu, {220}Cu, and {311}Cu, pole figures using the Los Alamos Preferred Orientation Package (popLA) after correction of the data with respect to measured background and calculated defocusing error.
(a) (b) Figure 4: Misorientation distribution plots for composite sample reduced to a) 73% reduction and b) 92% reduction
(a) (b) Figure 5: Grain diameter distribution plots for composite sample reduced to a) 73% reduction and b) 92% reduction
Online since: July 2011
Authors: Li Ming Zhang, Zai Quan Wang
The experimental data are shown in Table 1.
Table 1 Experimental data of unloading rock specimens Rock specimens Confining pressure /MPa Failure confining pressure /MPa Failure axial stress /MPa Failure axial stress difference /MPa 1# 40 19.8 182 162.2 2# 30 0.4 149 148.6 3# 30 12.5 181 168.5 4# 20 0.7 192 191.3 5# 20 4.3 164 159.7 6# 20 6.3 199 192.7 7# 10 4.1 148 143.9 8# 10 5.4 181 175.6 Fig.1 (a) shows the relationship between axial stress and axial strain under unloading condition.
Application experimental results to underground Rockburst control In the confining pressure reduction test, a specimen will fail in confining pressure reduction at the point where the axial stress is greater than its strength.
From the experiments of confining pressure reduction, it shows that rock fail during the process of confining stress reduction, i.e. rock can also fail during the change of stress condition, not only during the loading process.
Table 1 Experimental data of unloading rock specimens Rock specimens Confining pressure /MPa Failure confining pressure /MPa Failure axial stress /MPa Failure axial stress difference /MPa 1# 40 19.8 182 162.2 2# 30 0.4 149 148.6 3# 30 12.5 181 168.5 4# 20 0.7 192 191.3 5# 20 4.3 164 159.7 6# 20 6.3 199 192.7 7# 10 4.1 148 143.9 8# 10 5.4 181 175.6 Fig.1 (a) shows the relationship between axial stress and axial strain under unloading condition.
Application experimental results to underground Rockburst control In the confining pressure reduction test, a specimen will fail in confining pressure reduction at the point where the axial stress is greater than its strength.
From the experiments of confining pressure reduction, it shows that rock fail during the process of confining stress reduction, i.e. rock can also fail during the change of stress condition, not only during the loading process.