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Online since: January 2017
Authors: Shou Zhong Wang, Tong Zhang, Chun Hong Dong
The results are expected to provide useful experimental data and theoretical basis for the practical emergence disposal of methanol leakage.
However, at present no foam is reported in the emergency decontamination of methanol leakage and no relevant experimental data is available, so its actual application is limited.
The impact of the decontaminant amount and composition on the decontamination effect was studied, the decontamination mechanism of foam decontaminant on methanol was explored and the practicality of the foam decontaminant was assessed to provide experiment data and theoretical guidance for its application.
Experiment Results and Discussion The ratio between the reduction value of the methanol vapor concentration in the box after decontamination and the methanol vapor concentration in the air prior to decontamination is defined as the decontamination rate and is used as the decontamination efficiency assessment criteria
But the reduction of methanol vapor concentration is limited at a given water mist amount.
However, at present no foam is reported in the emergency decontamination of methanol leakage and no relevant experimental data is available, so its actual application is limited.
The impact of the decontaminant amount and composition on the decontamination effect was studied, the decontamination mechanism of foam decontaminant on methanol was explored and the practicality of the foam decontaminant was assessed to provide experiment data and theoretical guidance for its application.
Experiment Results and Discussion The ratio between the reduction value of the methanol vapor concentration in the box after decontamination and the methanol vapor concentration in the air prior to decontamination is defined as the decontamination rate and is used as the decontamination efficiency assessment criteria
But the reduction of methanol vapor concentration is limited at a given water mist amount.
Online since: October 2014
Authors: Viorel Goanta, Liviu Andrusca, Paul Doru Barsanescu
In theory, any material can be tested by stretching a biaxial cruciform specimen, but must be investigated in what way the shape of the specimen influence the data obtained.
In order to provide more useful data, cruciform specimens must satisfy a set of requirements: · possibility to align (center) the cruciform specimen in test system; · generation of homogeneous fields of biaxial stresses and strains in central part, large enough, so failure occur in the gage section; · localization of yielding in the central area; · possibility to observe evolution of stress state after yielding initiation; · to accept ratios of arbitrary biaxial loading, in order to generate an envelope of failure; · values of stresses in the region tested to be comparable to the nominal values obtained by dividing forces applied to the transverse area, etc.
To improve the biaxial stress state from the middle of the specimen was proceeded to a thickness reduction, the cutting up having various forms (Fig 1.b presents one of them).
By effectively combining three factors: geometrical shape, thickness reduction and introduction of the grooves can be obtained an optimal cruciform specimen.
Finite element modelling The concept of a multiaxial testing system capable of producing input data in constitutive relations for a particular type of material creates the perspective of reducing the number of tests performed, increasing the quality of the experiments and getting fast results that can be used later in the design process.
In order to provide more useful data, cruciform specimens must satisfy a set of requirements: · possibility to align (center) the cruciform specimen in test system; · generation of homogeneous fields of biaxial stresses and strains in central part, large enough, so failure occur in the gage section; · localization of yielding in the central area; · possibility to observe evolution of stress state after yielding initiation; · to accept ratios of arbitrary biaxial loading, in order to generate an envelope of failure; · values of stresses in the region tested to be comparable to the nominal values obtained by dividing forces applied to the transverse area, etc.
To improve the biaxial stress state from the middle of the specimen was proceeded to a thickness reduction, the cutting up having various forms (Fig 1.b presents one of them).
By effectively combining three factors: geometrical shape, thickness reduction and introduction of the grooves can be obtained an optimal cruciform specimen.
Finite element modelling The concept of a multiaxial testing system capable of producing input data in constitutive relations for a particular type of material creates the perspective of reducing the number of tests performed, increasing the quality of the experiments and getting fast results that can be used later in the design process.
Online since: October 2014
Authors: Lin Wu, Ting Ting Yang, Ming Wang Dong
Import the spiral curve data into SOLIDWORKS to complete the 3D modeling of cylindrical cam.
The institutions of this reducer is shown in Fig.1, consists of the box and the joint transmission reduction mechanism.
The secondary stage transmission is gear transmission, small gear linked with the rotating shaft though the spline and the meshing transmission of small gear and big gear can achieve the double reduction [7].
Considering the actual structure of cylindrical cam, select the spindle with keys as circumferential locating datum and radial locating datum when machining the cam, take spindle shoulder as axial positioning datum, tighten the cylindrical cam through the link between the nut and screw thread on the front of spindle.
First, take the box as datum, put in the assembled bearing cylindrical cam and orientate to prevent interference.
The institutions of this reducer is shown in Fig.1, consists of the box and the joint transmission reduction mechanism.
The secondary stage transmission is gear transmission, small gear linked with the rotating shaft though the spline and the meshing transmission of small gear and big gear can achieve the double reduction [7].
Considering the actual structure of cylindrical cam, select the spindle with keys as circumferential locating datum and radial locating datum when machining the cam, take spindle shoulder as axial positioning datum, tighten the cylindrical cam through the link between the nut and screw thread on the front of spindle.
First, take the box as datum, put in the assembled bearing cylindrical cam and orientate to prevent interference.
Online since: October 2022
Authors: Aigars Paze, Daniela Godina, Janis Rizhikovs, Rudolfs Berzins, Raimonds Makars, Arturs Teresko, Sanita Vitolina
The results indicate that the experimental data fits very well with the Langmuir adsorption model.
One procedure for particle size reduction is the top-down method, in which a micro- to nano- range betulin particle water dispersion can be obtained by high-energy mechanical breakdown.
In turn this leads to a reduction in specific surface area [16], which could be explained that there may be less electrostatic attraction between the MB cations and betulin particles surface, which may lead to a lower adsorption capacity.
In this study Langmuir adsorption model was used to describe the adsorption data.
The adsorption equilibrium data fits very well in a Langmuir isotherm model, which indicates that the surface of the studied betulin particles is energetically homogeneous and a monomolecular coverage was formed during adsorption.
One procedure for particle size reduction is the top-down method, in which a micro- to nano- range betulin particle water dispersion can be obtained by high-energy mechanical breakdown.
In turn this leads to a reduction in specific surface area [16], which could be explained that there may be less electrostatic attraction between the MB cations and betulin particles surface, which may lead to a lower adsorption capacity.
In this study Langmuir adsorption model was used to describe the adsorption data.
The adsorption equilibrium data fits very well in a Langmuir isotherm model, which indicates that the surface of the studied betulin particles is energetically homogeneous and a monomolecular coverage was formed during adsorption.
Online since: September 2011
Authors: Jing Hua Ding, Qian Yun Xi, Qing Yan Jiang, Yong Liang Zhang, Ping Gao, Xiao Tong Zhu, Hong Yi Li, Gang Shu, Song Bo Wang
These data showed that the 2 shRNA sequences were effective in suppressing SST expression and may provide an approach to down-regulate both in vitro and in vivo expression of porcine SST.
The data were considered to be acceptable when the coefficient of variance of 1 sample was smaller than 5%.
Data were expressed as mean ± standard error of the mean (SEM), and P values less than 0.05 were considered significant.
The results of the density analysis showed that the U6 levels in all the treatment groups were similar (P > 0.05); however, the expression of SST mRNAs in the LV-siRNA1- and LV-siRNA2-transfected cells showed significant reduction of 73.4% and 71.1% (P < 0.01) (Fig. 4C), respectively, in comparison with the expression levels in the negative control.
Different letters indicate that the differences were significant (P < 0.01).Expression of SST mRNAin LV-siRNA1- and LV-siRNA2-transfected cells showed significant reduction of 73.4% and 71.1% (P < 0.01).
The data were considered to be acceptable when the coefficient of variance of 1 sample was smaller than 5%.
Data were expressed as mean ± standard error of the mean (SEM), and P values less than 0.05 were considered significant.
The results of the density analysis showed that the U6 levels in all the treatment groups were similar (P > 0.05); however, the expression of SST mRNAs in the LV-siRNA1- and LV-siRNA2-transfected cells showed significant reduction of 73.4% and 71.1% (P < 0.01) (Fig. 4C), respectively, in comparison with the expression levels in the negative control.
Different letters indicate that the differences were significant (P < 0.01).Expression of SST mRNAin LV-siRNA1- and LV-siRNA2-transfected cells showed significant reduction of 73.4% and 71.1% (P < 0.01).
Online since: October 2011
Authors: Shu Lin Zhan, Jun Ying Lai, Fang Huang
To make the monitoring systems more efficient and capture structural damage characteristic data more accurately with help of optimal sensor placement (OSP).
Currently, the common traditional optimal sensor placement methods include effective independence method (EFI) [3], Guyan model reduction method, modal kinetic energy optimization method (EOT), eigenvalue sensitivity analysis etc.
(1) Establish a high-level finite element model and make numerical analysis to obtain the dynamic characteristic data, and extract the modal matrix of all the candidate points
The data of structure modal analysis were run in MATLAB environment combined with the method functions and obtain the optimal results of 4 to 19 degrees of freedom in X direction and Y direction.
From Fig. 4 and Fig. 5, we can see that at 6 point, MAC value has a sudden reduction and after 6 point the curve becomes gentle and the MAC value of the largest off-diagonal element is minimum when placing sensors to every point of the structure.
Currently, the common traditional optimal sensor placement methods include effective independence method (EFI) [3], Guyan model reduction method, modal kinetic energy optimization method (EOT), eigenvalue sensitivity analysis etc.
(1) Establish a high-level finite element model and make numerical analysis to obtain the dynamic characteristic data, and extract the modal matrix of all the candidate points
The data of structure modal analysis were run in MATLAB environment combined with the method functions and obtain the optimal results of 4 to 19 degrees of freedom in X direction and Y direction.
From Fig. 4 and Fig. 5, we can see that at 6 point, MAC value has a sudden reduction and after 6 point the curve becomes gentle and the MAC value of the largest off-diagonal element is minimum when placing sensors to every point of the structure.
Online since: November 2024
Authors: Lia-Nicoleta Botila, Ion Aurel Perianu, Emilia-Florina Binchiciu, Gabriela-Victoria Mnerie, Emilia Dobrin, Radu Nicolae Popescu
This joining process has multiple benefits, including the creation of very fine grains in the microstructure, uniform appearance of the welded surface, reduced surface roughness, elimination/reduction of the formation of brittle intermetallic compounds and coarse secondary phases, and facilitation of desired chemical reactions [2].
a) b) Fig. 6 Variants of taper pin welding tools chosen for the experimental part: a) smooth, b) with 4 flat bevels Put dimensions on the pictures of tool length, shoulder diameter, pin length, pin diameter (values are taken from the table of experimental data). 2.3.
Welding process parameters FSW and SFSW Data on joining materials, tools used and process parameters are given in Table 5.
Table 5 Data on materials, tools and process parameters of FSW and SFSW welding processes Welding process [-] Material tool [-] Diameter Sholder [Ø] Pin type [-] Diameter pin [Ø] Pin Length [-] Rotation tool speed [rpm] Welding speed [mm/min] Rotation sense[-] Water temperature for SFSW [0C] No. experiment [-] Befor welding After welding FSW P20S 22 Smooth taper pin 4,5 3,3 1200 60 Counter-clockwise NA NA 6(A) 1300 50 NA NA 6(B) SFSW 1200 60 18° 29° 6A/V3 (A) 1300 50 19° 30° 6A/V3 (B) FSW Taper pin with 4 flat bevels 5 3,82 1200 60 NA NA 7(A) 1300 50 NA NA 7(B) SFSW 1200 60 14° 17° 7A/V3 (A) 1300 50 19° 22° 7A/V3 (B) FSW welding in liquid medium was performed using an enclosure (2, Fig. 5) placed on the FSW welding machine.
In the case of SFSW with smooth taper pin resulted a significant reduction of the joint size compared to FSW, due to the liquid (water) environment in which the SFSW process took place; - Using a tapered pin with 4 flat weaves in the FSW process the values of the upper base approach those of the tool shoulder, and the values of the joint root have values approximately half of those of the lower base.
a) b) Fig. 6 Variants of taper pin welding tools chosen for the experimental part: a) smooth, b) with 4 flat bevels Put dimensions on the pictures of tool length, shoulder diameter, pin length, pin diameter (values are taken from the table of experimental data). 2.3.
Welding process parameters FSW and SFSW Data on joining materials, tools used and process parameters are given in Table 5.
Table 5 Data on materials, tools and process parameters of FSW and SFSW welding processes Welding process [-] Material tool [-] Diameter Sholder [Ø] Pin type [-] Diameter pin [Ø] Pin Length [-] Rotation tool speed [rpm] Welding speed [mm/min] Rotation sense[-] Water temperature for SFSW [0C] No. experiment [-] Befor welding After welding FSW P20S 22 Smooth taper pin 4,5 3,3 1200 60 Counter-clockwise NA NA 6(A) 1300 50 NA NA 6(B) SFSW 1200 60 18° 29° 6A/V3 (A) 1300 50 19° 30° 6A/V3 (B) FSW Taper pin with 4 flat bevels 5 3,82 1200 60 NA NA 7(A) 1300 50 NA NA 7(B) SFSW 1200 60 14° 17° 7A/V3 (A) 1300 50 19° 22° 7A/V3 (B) FSW welding in liquid medium was performed using an enclosure (2, Fig. 5) placed on the FSW welding machine.
In the case of SFSW with smooth taper pin resulted a significant reduction of the joint size compared to FSW, due to the liquid (water) environment in which the SFSW process took place; - Using a tapered pin with 4 flat weaves in the FSW process the values of the upper base approach those of the tool shoulder, and the values of the joint root have values approximately half of those of the lower base.
Online since: January 2017
Authors: Siti Aslamyah, Haryati Haryati, Zainuddin Zainuddin
The data was collected then it was compiled and arranged based on statistic data from South Sulawesi book in Numeral [4].
Determine the fructose content Weigh the solid material which has been refined or 2,5-25 of liquid material which depends on reduction its glucose content.
Take 25 ml of free filtrate that has about 15-60 mg of reduction sugar and then add about 25 ml of Luff-Schoorl solution in Erlenmeyer.
Glucose determining seem like sugar reduction determining where it divided 0,9 weight of glucose which is mean a weight of starch.
The distribution map regional of carbohydrate material producer Based on survey finding and the investigation of data from BPS of South Sulawesi (2014), the carbohydrate production in South Sulawesi which can be seen in the Figure 1.
Determine the fructose content Weigh the solid material which has been refined or 2,5-25 of liquid material which depends on reduction its glucose content.
Take 25 ml of free filtrate that has about 15-60 mg of reduction sugar and then add about 25 ml of Luff-Schoorl solution in Erlenmeyer.
Glucose determining seem like sugar reduction determining where it divided 0,9 weight of glucose which is mean a weight of starch.
The distribution map regional of carbohydrate material producer Based on survey finding and the investigation of data from BPS of South Sulawesi (2014), the carbohydrate production in South Sulawesi which can be seen in the Figure 1.
Online since: October 2015
Authors: Andreas Sterzing, Markus Bergmann, Dirk Landgrebe
An alternating reduction and expansion occurs.
In the investigated angular die geometry (II) the effective strain value is calculated by summing up the reduction, upsetting and shearing steps.
The lower data series are measured on the samples before the material is significantly deformed.
The two higher data series show the hardness measurement of the completely deformed material.
The presented data displays initial analytical and experimental results.
In the investigated angular die geometry (II) the effective strain value is calculated by summing up the reduction, upsetting and shearing steps.
The lower data series are measured on the samples before the material is significantly deformed.
The two higher data series show the hardness measurement of the completely deformed material.
The presented data displays initial analytical and experimental results.
Online since: November 2015
Authors: Predrag Dašić, Adolfo Senatore, Mario Pisaturo
In fact, AMTs allow strong improvement in terms of safety, comfort, reliability, shifting quality, and driving performance, together with reduction of fuel consumption and pollutant emissions [1-6].
In fact, to reach high performances is fundamental to implement a dependable control scheme in order to achieve reduction of fuel consumption, short gearshift time, reduction of facing wear and passengers comfort.
Firstly, the inference of the temperature, of the contact pressure and of the sliding speed on the friction coefficient have been analyzed in order to get useful data about the behaviour of the clutch facings in a wide range of rubbing conditions.
Based on the experimental results in Fig. 3 [5], the function that better fits the experimental data, for strictly positive slip speed, is given by tanh function in (2); vs is the local sliding speed, Dm and g have been identified with the corresponding values equal to 0.09 and 2 s/m, respectively.
The calculation is referred to pull-type clutch system for passenger car with the following data: - inner-outer clutch disc diameter: 135-190 mm; - friction coefficient behaviour as in Fig. 3 and (2,3) for speed and pressure dependence; thermal behaviour as in [25]; - cushion spring load-deflection curve as in [4]; - number of lever spring elements: 8.
In fact, to reach high performances is fundamental to implement a dependable control scheme in order to achieve reduction of fuel consumption, short gearshift time, reduction of facing wear and passengers comfort.
Firstly, the inference of the temperature, of the contact pressure and of the sliding speed on the friction coefficient have been analyzed in order to get useful data about the behaviour of the clutch facings in a wide range of rubbing conditions.
Based on the experimental results in Fig. 3 [5], the function that better fits the experimental data, for strictly positive slip speed, is given by tanh function in (2); vs is the local sliding speed, Dm and g have been identified with the corresponding values equal to 0.09 and 2 s/m, respectively.
The calculation is referred to pull-type clutch system for passenger car with the following data: - inner-outer clutch disc diameter: 135-190 mm; - friction coefficient behaviour as in Fig. 3 and (2,3) for speed and pressure dependence; thermal behaviour as in [25]; - cushion spring load-deflection curve as in [4]; - number of lever spring elements: 8.