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Online since: November 2011
Authors: Gong Shu Lu, Cun Bin Li, Xian Li
Because the power is generated by energy-saving units instead of high energy-consumption ones, the mechanism is conducive to achieve the objectives of energy saving and emission reduction.
As a policy risk factor under the premise of energy saving and emission reduction, generation right may lead to a series of risks especially for the participators.
In GRT market, energy saving and emission reduction generators will buy the generation right and the high energy consumption and large emission units sell their generation rights.
Based on the data in table 3, the Efficient frontier curves can be drawn as Figure 1.
Study on Optimal Generation Right Exchange Mechanism Based on Energy Saving and Emission Reduction.
As a policy risk factor under the premise of energy saving and emission reduction, generation right may lead to a series of risks especially for the participators.
In GRT market, energy saving and emission reduction generators will buy the generation right and the high energy consumption and large emission units sell their generation rights.
Based on the data in table 3, the Efficient frontier curves can be drawn as Figure 1.
Study on Optimal Generation Right Exchange Mechanism Based on Energy Saving and Emission Reduction.
Online since: November 2011
Authors: Mahdi Maarefdoust
The mathematical model developed using FLUENT software in almost real conditions of the process was solved and the results match well with the data resolution in the laboratory had a real case [5].
Theory and modeling problem: the issue in two cases and obtain the optimum angle of the form (in which the angular angle, with equal percentage reduction, less power is needed for extruded) for extruded sections together and form templates for the modeling and cross section be analyzed.
Percent reduction in cross section is considered.
According to the equal percentage reduction dies, curves (c), (b), (d) and (b) respectively for the minimum force need extruded billet.
Thus, using such methods can be a real industrial process with the lowest model simplification and reduction of heavy costs in the practical test design process and minimize problems in producing parts and optimizing effective step removal products.
Theory and modeling problem: the issue in two cases and obtain the optimum angle of the form (in which the angular angle, with equal percentage reduction, less power is needed for extruded) for extruded sections together and form templates for the modeling and cross section be analyzed.
Percent reduction in cross section is considered.
According to the equal percentage reduction dies, curves (c), (b), (d) and (b) respectively for the minimum force need extruded billet.
Thus, using such methods can be a real industrial process with the lowest model simplification and reduction of heavy costs in the practical test design process and minimize problems in producing parts and optimizing effective step removal products.
Online since: May 2011
Authors: Ji Min Zhai, Xi Wen Song, Fen Zhou, Sheng Li An
One effective approach for cost reduction is to decrease the operating temperature.
However, the reduction in operating temperature limits the cell performance.
Sm0.5Sr0.5CoO3 (SSC) exhibited higher electrical conductivity (up to 103 S·cm-1), enhanced catalytic activity for oxygen reduction and good compatibility with ceria electrolyte [14,15].
The polarization resistance of SGSC-GDC composite cathodes was calculated using the measured data, which is shown in Fig.4.
Generally, the mechanism of oxygen reduction in cathode related to the following [22-24] : (ⅰ) diffusion and adsorption of gas phase oxygen molecule to cathode surface; (ⅱ) dissociation and ionization of the adsorbed oxygen molecule; (ⅲ) ionic diffusion and conduction of the adsorbed oxygen ion in the bulk electrode; (ⅳ) ionic transfer at the interface between the electrode and the electrolyte.
However, the reduction in operating temperature limits the cell performance.
Sm0.5Sr0.5CoO3 (SSC) exhibited higher electrical conductivity (up to 103 S·cm-1), enhanced catalytic activity for oxygen reduction and good compatibility with ceria electrolyte [14,15].
The polarization resistance of SGSC-GDC composite cathodes was calculated using the measured data, which is shown in Fig.4.
Generally, the mechanism of oxygen reduction in cathode related to the following [22-24] : (ⅰ) diffusion and adsorption of gas phase oxygen molecule to cathode surface; (ⅱ) dissociation and ionization of the adsorbed oxygen molecule; (ⅲ) ionic diffusion and conduction of the adsorbed oxygen ion in the bulk electrode; (ⅳ) ionic transfer at the interface between the electrode and the electrolyte.
Online since: November 2012
Authors: João F. Trencher Martins, Robinson A. dos Santos, Fabio E. da Costa, Carlos H. de Mesquita, Margarida M. Hamada
However, the role of crystal impurities on the detector performance is crucial, then improvements on the chemical purification and the impurity reduction analysis should be achieved [2,3].
Following the same procedure, the obtained crystals were re-grown by twice aiming to purify the crystals (second purification), since the reduction of impurities at each growth is expected.
As it can be observed from this figure, there was a significant reduction of the impurities after the first growth, compared to those found in the raw material.
The stoichiometry of HgI2, the semi quantitative scanning of the elements present on the surface of the crystal purified twice and the elemental composition from the residual salt, after the crystal growth, were performed by SEM-BSE to evaluate the efficiency of HgI2 purification by the PVT technique: all these data are summarized in Table 1.
This information allows the reduction in the concentration of these elements to be accompanied, after each purification process.
Following the same procedure, the obtained crystals were re-grown by twice aiming to purify the crystals (second purification), since the reduction of impurities at each growth is expected.
As it can be observed from this figure, there was a significant reduction of the impurities after the first growth, compared to those found in the raw material.
The stoichiometry of HgI2, the semi quantitative scanning of the elements present on the surface of the crystal purified twice and the elemental composition from the residual salt, after the crystal growth, were performed by SEM-BSE to evaluate the efficiency of HgI2 purification by the PVT technique: all these data are summarized in Table 1.
This information allows the reduction in the concentration of these elements to be accompanied, after each purification process.
Online since: June 2014
Authors: M.K. Roslim, Suhaimi Hassan, K. Izzati
Besides that, significant reduction in boiler operating pressure may cause the boiler circulation to be interrupted without some modification on the existing piping, tubes etc. [14].
The data was collected with initial operating pressure of 0 bar until the operating pressure was build up to 7 bar.
The reduction in heat transfer for low width ratio and high twist ratio might be due to the weakening of disturbance at the boundary layer of the air flow.
Any reduction in number of coil plates inside boiler reduced their efficiency greatly.
[14] Information on http://www1.eere.energy.gov/manufacturing/tech_assistance/pdfs/steam_pressure_reduction.pdf
The data was collected with initial operating pressure of 0 bar until the operating pressure was build up to 7 bar.
The reduction in heat transfer for low width ratio and high twist ratio might be due to the weakening of disturbance at the boundary layer of the air flow.
Any reduction in number of coil plates inside boiler reduced their efficiency greatly.
[14] Information on http://www1.eere.energy.gov/manufacturing/tech_assistance/pdfs/steam_pressure_reduction.pdf
Online since: October 2016
Authors: K. Karthik, R. Rohith Renish, I. Irfan Ahmed, T. Niruban Projoth
Introduction
Vibrations are undesirable for structures, owing to the need for structural stability, position control, durability, performance and noise reduction.
Performance and noise reduction.
Vibration are of concern to large structures such as air craft, as well as small structures such as electronics, vibration reduction can be attained by increasing the damping capacity (loss of energy) and/or increasing the stiffness (storage modulus).
The loss modulus is the product of these two quantities and thus can be considered a figure of merit for the vibration reduction.
Elejabarrieta. (2011) ‘Dynamic Characterization of High Damping Viscoelastic Materials from Vibration Test data’, Journal of Sound and Vibration, Vol. 330, PP. 3930–3943
Performance and noise reduction.
Vibration are of concern to large structures such as air craft, as well as small structures such as electronics, vibration reduction can be attained by increasing the damping capacity (loss of energy) and/or increasing the stiffness (storage modulus).
The loss modulus is the product of these two quantities and thus can be considered a figure of merit for the vibration reduction.
Elejabarrieta. (2011) ‘Dynamic Characterization of High Damping Viscoelastic Materials from Vibration Test data’, Journal of Sound and Vibration, Vol. 330, PP. 3930–3943
Online since: September 2013
Authors: Yao Jun Ge, Wen Ming Zhang
., Nanjing 210096, China
2 State Key Lab for Disaster Reduction in Civil Engineering, Tongji Univ., Shanghai 200092, China
awenmingzhang@hotmail.com, byaojunge@tongji.edu.cn
Keywords: Aerodynamics, Flutter, Wind tunnel test, Full bridge aeroelastic model, Three-tower suspension bridge, Erection
Abstract: As a new long-span suspension bridge with double main spans and a typical closed streamline cross-section of single box deck, the flutter performance of the Maanshan Bridge during erection was investigated via a full bridge aeroelastic model test.
As it is well known to all, flutter-type aerodynamic instability of suspension bridges is more prone to occur during the early erection stage of the deck because of the significant reduction of overall torsional stiffness in particular.
Fig.1 Elevation of Maanshan Bridge (unit: m) Fig.2 Deck cross-section (unit: mm) According to the observation data, the exponent of mean wind profile at the bridge site is about 0.12, and the basic wind speed at the bridge site (U10), namely the yearly-maximum 10-min averaged mean wind speed at 10m height corresponding to 100-year return period, is 31.8 m/s.
sequence A-V-1 A-L-1 S-L-1 A-T-1 S-T-1 1 18.2% 0.1060 - - - - 2 25.8% 0.1030 0.6046 0.6745 0.4416 0.4434 3 33.3% 0.1032 0.3395 0.3888 0.4311 0.4765 4 40.9% 0.1047 0.1471 0.1473 0.3722 0.3989 5 48.5% 0.1014 0.0895 0.0900 0.3479 0.4077 6 56.1% 0.0969 0.0941 0.0957 0.3525 0.4021 7 63.6% 0.0933 0.0901 0.0921 0.2758 0.3243 8 71.2% 0.0910 0.0842 0.0860 0.2780 0.3254 9 78.8% 0.0896 0.0790 0.0804 0.2525 0.3167 10 86.4% 0.0888 0.0750 0.0761 0.2483 0.3121 11 92.4% 0.0885 0.0731 0.0739 0.2492 0.3128 12 98.5% 0.0883 0.0743 0.0749 0.2616 0.3306 13 100% 0.0883 0.1024 0.1041 0.2819 0.3578 Note: P%–percentage of deck completion; S–symmetric, A–anti-symmetric, V–vertical, L–lateral, T–torsional Fig.3 Evolution of fundamental frequencies Note: S–symmetric, A–anti-symmetric, V–vertical, L–lateral, T–torsional Fig.4 Evolution of frequency ratio Full aeroelastic model The full bridge aeroelastic model test was carried out in the TJ-3 Wind Tunnel of the State Key Laboratory for Disaster Reduction
Analysis and wind tunnel study on wind-resistant performance of the Maanshan Bridge over Yangtze River—part I: wind tunnel test of sectional model, Research Report No.WT200802, State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University, Shanghai, China (2008).
As it is well known to all, flutter-type aerodynamic instability of suspension bridges is more prone to occur during the early erection stage of the deck because of the significant reduction of overall torsional stiffness in particular.
Fig.1 Elevation of Maanshan Bridge (unit: m) Fig.2 Deck cross-section (unit: mm) According to the observation data, the exponent of mean wind profile at the bridge site is about 0.12, and the basic wind speed at the bridge site (U10), namely the yearly-maximum 10-min averaged mean wind speed at 10m height corresponding to 100-year return period, is 31.8 m/s.
sequence A-V-1 A-L-1 S-L-1 A-T-1 S-T-1 1 18.2% 0.1060 - - - - 2 25.8% 0.1030 0.6046 0.6745 0.4416 0.4434 3 33.3% 0.1032 0.3395 0.3888 0.4311 0.4765 4 40.9% 0.1047 0.1471 0.1473 0.3722 0.3989 5 48.5% 0.1014 0.0895 0.0900 0.3479 0.4077 6 56.1% 0.0969 0.0941 0.0957 0.3525 0.4021 7 63.6% 0.0933 0.0901 0.0921 0.2758 0.3243 8 71.2% 0.0910 0.0842 0.0860 0.2780 0.3254 9 78.8% 0.0896 0.0790 0.0804 0.2525 0.3167 10 86.4% 0.0888 0.0750 0.0761 0.2483 0.3121 11 92.4% 0.0885 0.0731 0.0739 0.2492 0.3128 12 98.5% 0.0883 0.0743 0.0749 0.2616 0.3306 13 100% 0.0883 0.1024 0.1041 0.2819 0.3578 Note: P%–percentage of deck completion; S–symmetric, A–anti-symmetric, V–vertical, L–lateral, T–torsional Fig.3 Evolution of fundamental frequencies Note: S–symmetric, A–anti-symmetric, V–vertical, L–lateral, T–torsional Fig.4 Evolution of frequency ratio Full aeroelastic model The full bridge aeroelastic model test was carried out in the TJ-3 Wind Tunnel of the State Key Laboratory for Disaster Reduction
Analysis and wind tunnel study on wind-resistant performance of the Maanshan Bridge over Yangtze River—part I: wind tunnel test of sectional model, Research Report No.WT200802, State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University, Shanghai, China (2008).
Online since: June 2011
Authors: Thotsaphon Threrujirapapong, Hiroyuki Fukuda, Junko Umeda, Katsuyoshi Kondoh
According to the data sheet, mean diameter and length of the CNT were 9.5 nm and 1.5 μm, respectively.
They observed the reduction of surface oxide layer of the Al alloy powder by the diffused Mg from the powder inside over 500°C.
It is obvious that high temperature heating facilitates the reduction of surface oxide into Mg oxide species such as MgO and MgAl2O4 [19, 20].
Therefore, the Mg concentration around CNTs could be reasonably concluded due to the reduction of Al oxide species formed by the desorbed water and O2 from CNTs during the sample fabrication process.
This means that Mg concentration around CNTs was due to the reduction of Al oxide species formed by the desorbed water and O2 from CNTs during the sample fabrication process.
They observed the reduction of surface oxide layer of the Al alloy powder by the diffused Mg from the powder inside over 500°C.
It is obvious that high temperature heating facilitates the reduction of surface oxide into Mg oxide species such as MgO and MgAl2O4 [19, 20].
Therefore, the Mg concentration around CNTs could be reasonably concluded due to the reduction of Al oxide species formed by the desorbed water and O2 from CNTs during the sample fabrication process.
This means that Mg concentration around CNTs was due to the reduction of Al oxide species formed by the desorbed water and O2 from CNTs during the sample fabrication process.
Online since: July 2017
Authors: Lu Liu, Xiang Gao, Cheng Hang Zheng
Titania supported vanadium oxide (V2O5/TiO2) catalysts are excellent catalysts not only for the reduction of nitrogen oxides with NH3 but also for processes of selective oxidation [5-11].
Kamata [17] found V2O5/TiO2 showed high Hg0 oxidation activity, and this result is in good agreement with the data from other literature and experiments [16, 19].
Three catalyst samples were obtained as follows: (a) the dried precursor was directly calcined at 500 oC for 5 h in the air and denoted as V2O5/TiO2-C; (b) the dried precursor firstly was put into the discharging tube for decomposed and reduction in the air atmosphere for 40 min by DBD plasma, and then the plasma-treated sample was calcined at 500 oC for 5 h in the air, the final sample was nominated as V2O5/TiO2-PC; (c) the dried precursor was firstly calcined at 500 oC for 5 h in the air, then the calcined catalyst was put into the discharging tube and treated by DBD plasma in the air atmosphere for 40 min.
Yang, Low-temperature selective catalytic reduction of NO with NH3 over iron and manganese oxides supported on titania, Appl.
Cen, Mercury Oxidation over a Vanadia-based Selective Catalytic Reduction Catalyst, Energ.
Kamata [17] found V2O5/TiO2 showed high Hg0 oxidation activity, and this result is in good agreement with the data from other literature and experiments [16, 19].
Three catalyst samples were obtained as follows: (a) the dried precursor was directly calcined at 500 oC for 5 h in the air and denoted as V2O5/TiO2-C; (b) the dried precursor firstly was put into the discharging tube for decomposed and reduction in the air atmosphere for 40 min by DBD plasma, and then the plasma-treated sample was calcined at 500 oC for 5 h in the air, the final sample was nominated as V2O5/TiO2-PC; (c) the dried precursor was firstly calcined at 500 oC for 5 h in the air, then the calcined catalyst was put into the discharging tube and treated by DBD plasma in the air atmosphere for 40 min.
Yang, Low-temperature selective catalytic reduction of NO with NH3 over iron and manganese oxides supported on titania, Appl.
Cen, Mercury Oxidation over a Vanadia-based Selective Catalytic Reduction Catalyst, Energ.
Online since: June 2015
Authors: O.I. Nokhrina, I.E. Proshunin, I.D. Rozhihina, I.E. Hodosov, V.G. Osipova
The concentrate is difficult to use for out-of-furnace aluminothermic manganese smelting because the heat, generated in the course of reduction reaction, does not provide effective separation of metal and slag.
Aluminothermic process of Mn3O4 reduction reaction can be described as follows: Mn3O4 + 8/3Al = 3Mn + 4/3Al2O3.
There are no data on possibility of oxidation of Mn3O4 to Mn2О3 or MnO2.
Table. 4 Technical analysis of reducing agents Reducing agent Characteristic Content [С] in working mass, % Аd (ash), % Vdaf (volatile), % Wr (wapour), % Brown coal 2B 49.1 7.83 46.76 35.3 Parabituminous coal D 55.6 5.64 43.53 15.4 Low-caking coal SS 70.02 6.4 34.3 6.4 Coke nut 84.56 9.41 1.83 3.0 Ferrum reduction from iron ore oxides were examined at reducing roasting temperatures 800 о С, 900 оС, 1000 оС, 1100 оС and 1200 °C.
Effect of physical- chemical properties of various coal grades on solid-phase reduction of ferrum from iron ore oxides was determined.
Aluminothermic process of Mn3O4 reduction reaction can be described as follows: Mn3O4 + 8/3Al = 3Mn + 4/3Al2O3.
There are no data on possibility of oxidation of Mn3O4 to Mn2О3 or MnO2.
Table. 4 Technical analysis of reducing agents Reducing agent Characteristic Content [С] in working mass, % Аd (ash), % Vdaf (volatile), % Wr (wapour), % Brown coal 2B 49.1 7.83 46.76 35.3 Parabituminous coal D 55.6 5.64 43.53 15.4 Low-caking coal SS 70.02 6.4 34.3 6.4 Coke nut 84.56 9.41 1.83 3.0 Ferrum reduction from iron ore oxides were examined at reducing roasting temperatures 800 о С, 900 оС, 1000 оС, 1100 оС and 1200 °C.
Effect of physical- chemical properties of various coal grades on solid-phase reduction of ferrum from iron ore oxides was determined.