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Online since: October 2014
Authors: Adrian Alexandru Şerbănoiu, Marina Verdeș, Gabriel Teodoriu, Bogdan Serbanoiu, Ion Serbanoiu, Marius Costel Balan
From the perspective of the European Union, which proposes as major objectives: combating the climate change; limiting the vulnerability of EU imports of hydrocarbons; promoting the economic growth and as well as new jobs by ensuring energy with accessible prices - it is proposed as the minimum requirements that by 2020: 20% reduction of energy consumption through energy efficiency and economic development; 20% of the global consumption of energy to be from renewable sources (> 10% bio-fuels); 20% reduction of GHG emissions
Such a scientific approach is all the more interesting as the residential buildings, and not only, have a significant weight in terms of energy consumption, of which approximately 67% is used for heating purposes, which can add to the requirements of the European Union, as in a limited horizon of time, the vast majority of buildings, regardless of the fact that they are new or rehabilitated, to tend to a near-zero energy consumption.
ultimate energy source [RON/kWh] Solar systems ACS – aperture solar collector (absorber) [m2]; η0 – efficiency collector factor to zero losses; a1 (k1) – heat loss coefficient of solar collector, the aperture area [W/(m2•K)]; a2(k2) – enotes the dependence factor temperature coefficient of heat losses of the collector, aperture area, [W/(m2•K2)]; CSS – solar system cost relative to the surface of the absorber [RON/m2]; Solar water heaters Heat accumulators V – the volume of the storage tank [l] CRS –unit cost of the storage tank volume [RON/l] Radiators PR –nominal installed thermal power of the radiator [kW]; ttur –maximum heating temperature [oC] CPR –the unit cost of installed power for radiators [RON/kW] Underfloor heating AFH – heat exchange surface [m2]; ttur – maximum heating temperature[oC] CSE –the emisiv system cost related to the unit of heat exchange surface [RON/m2] We present, the centralized matrix of the results obtained from numerical simulations-indicative data
ultimate energy source [RON/kWh] Solar systems ACS – aperture solar collector (absorber) [m2]; η0 – efficiency collector factor to zero losses; a1 (k1) – heat loss coefficient of solar collector, the aperture area [W/(m2•K)]; a2(k2) – enotes the dependence factor temperature coefficient of heat losses of the collector, aperture area, [W/(m2•K2)]; CSS – solar system cost relative to the surface of the absorber [RON/m2]; Solar water heaters Heat accumulators V – the volume of the storage tank [l] CRS –unit cost of the storage tank volume [RON/l] Radiators PR –nominal installed thermal power of the radiator [kW]; ttur –maximum heating temperature [oC] CPR –the unit cost of installed power for radiators [RON/kW] Underfloor heating AFH – heat exchange surface [m2]; ttur – maximum heating temperature[oC] CSE –the emisiv system cost related to the unit of heat exchange surface [RON/m2] We present, the centralized matrix of the results obtained from numerical simulations-indicative data
Online since: November 2015
Authors: F. Abdullah Sultan, R. Panneer
Preheating Titanium helps in substantially increasing the tool life and improving machinability [3].The principle behind Pre-heating is increasing the difference in hardness between cutting tool and work piece thereby leading to a reduction in the component forces, improved surface finish and longer tool life.
M.Nouari and H.Makich [8] have stated in their research work that a reduction of cutting forces is noticed when the cutting speed increases, owing to the thermal softening of the material caused due to the temperature rise applied externally.
Taguchi has created a transformation of the repetition data to another value which is a response measure of the variation present which is known as signal-to-noise ratio(S/N) presented in Table 3.
M.Nouari and H.Makich [8] have stated in their research work that a reduction of cutting forces is noticed when the cutting speed increases, owing to the thermal softening of the material caused due to the temperature rise applied externally.
Taguchi has created a transformation of the repetition data to another value which is a response measure of the variation present which is known as signal-to-noise ratio(S/N) presented in Table 3.
Online since: April 2022
Authors: Laela Fitriyantina, I Gde Budi Indrawan, Doni Prakasa Eka Putra
The Q-value was calculated using the following equation (1) [4]:
Q= RQDJn × JrJa × JwSRF (1)
where RQD = value of Rock Quality Designation; Jn = amount of discontinuity set; Jr = roughness of the discontinuity surface; Ja = the weathering and filling level of the discontinuity surface; Jw = the pressure and water inflow; SRF = stress reduction factor.
On the other hand, one of the advantages of the Q-system is the rock mass classification includes the SRF (stress reduction factor) parameter, which considers the characteristics of particular zones [1].
The authors would like to thank the Ciliwung Cisadane River Basin Organization for the permission to do research and publish the site investigation data.
On the other hand, one of the advantages of the Q-system is the rock mass classification includes the SRF (stress reduction factor) parameter, which considers the characteristics of particular zones [1].
The authors would like to thank the Ciliwung Cisadane River Basin Organization for the permission to do research and publish the site investigation data.
Online since: March 2012
Authors: Xiao Jing Li, Zhi Hua Gao, Hui Guo, Pei Xin Qu
At the same time, dealing with complex geometric shape still needed other senior characteristics options which included scanning, lofting convex platform/matrix and the localization characteristics of datum axis and datum plane.
When reduction gears is at fault, It often engenders phenomena that gear oil of reduction gears has been emulsified, and the bearing has been rust and corrosion and damaged, which was caused by clotted moisture produced by gear oil in the process that was from hot to cold.
When reduction gears is at fault, It often engenders phenomena that gear oil of reduction gears has been emulsified, and the bearing has been rust and corrosion and damaged, which was caused by clotted moisture produced by gear oil in the process that was from hot to cold.
Online since: May 2012
Authors: Zhao Hua Jiang, Dong Yun Ma, Yu Guang Lv, Ying Wang, Huan Yuan, Hong Liu, Yong Chang Zhu, Yun Jie Zhang, Wei Fang
From crystal data show, it can be observed that there are difference in two kinds of Eu-O bond length from TPPO ligands and TTA anions.
The absorption of P=O in free TPPO shifted from 1184 cm−1 to around 1165 cm−1 meanwhile the appearance of peak at 535 cm−1 due to stretching vibration of Eu–O which indicates the coordination between TPPO,HTTA and Tb3+.The peak of O-H antisymmetric stretching in coodinated HTTA at 3430 cm-1 was weakened compared with enol O-H in free HTTA at 3420 cm-1 .The asymmetric stretching peak of C = O close to thiophene ring shifted from 1656 to 1602 cm-1, the peak close to strong electronegative trifluoromethyl from 1620 to 1524 cm-1 in HTTA,this carbonyl redshift indicates reduction in C = O bond strength after carbonyl oxygen coordinated to europium ions.
Alterations in bond strength lead to shifts of infrared absorption position as well as changes in intensity after the two legands coordination to Eu3+ ion,The absorption of C = C shifted from1597 cm-1 to 1537 cm-1 after coordination.So wave numbers reduction in C = C and C = O reflects average between single and double bonds[6]in chelate rings.
The absorption of P=O in free TPPO shifted from 1184 cm−1 to around 1165 cm−1 meanwhile the appearance of peak at 535 cm−1 due to stretching vibration of Eu–O which indicates the coordination between TPPO,HTTA and Tb3+.The peak of O-H antisymmetric stretching in coodinated HTTA at 3430 cm-1 was weakened compared with enol O-H in free HTTA at 3420 cm-1 .The asymmetric stretching peak of C = O close to thiophene ring shifted from 1656 to 1602 cm-1, the peak close to strong electronegative trifluoromethyl from 1620 to 1524 cm-1 in HTTA,this carbonyl redshift indicates reduction in C = O bond strength after carbonyl oxygen coordinated to europium ions.
Alterations in bond strength lead to shifts of infrared absorption position as well as changes in intensity after the two legands coordination to Eu3+ ion,The absorption of C = C shifted from1597 cm-1 to 1537 cm-1 after coordination.So wave numbers reduction in C = C and C = O reflects average between single and double bonds[6]in chelate rings.
Online since: October 2018
Authors: Elena V. Rzhevskaya, Elina V. Khakyasheva, Diana M. Khakulova, Azamat A. Zhansitov, Azamat L. Slonov, S.Yu. Khashirova
In the filled composites there is a significant reduction in the impact viscosity, while on the stress – strain diagram a yield point disappears, there is embrittlement of the material.
This effect of carbon fiber on impact strength means a reduction in the relative contribution of plastic deformation to the impact strength of filled composites, i.e. the impact strength of the studied samples is determined to a greater degree by the strength of the composite and the resistance to the propagation of fracture.
Thus, based on the analysis of the data of Table. 1, CF with a particle length of 0.2 mm as a filler suppresses the contribution of plastic deformation of the PPSS during impact tests to a slightly lesser extent than a carbon fiber with a particle length of 3 mm.
This effect of carbon fiber on impact strength means a reduction in the relative contribution of plastic deformation to the impact strength of filled composites, i.e. the impact strength of the studied samples is determined to a greater degree by the strength of the composite and the resistance to the propagation of fracture.
Thus, based on the analysis of the data of Table. 1, CF with a particle length of 0.2 mm as a filler suppresses the contribution of plastic deformation of the PPSS during impact tests to a slightly lesser extent than a carbon fiber with a particle length of 3 mm.
Online since: February 2007
Authors: Tao Yan, Xiao Lin Liu, Jian Feng Chen
Large synergistic effects over copper-containing ceria
were reported for CO oxidation [9], SO2 reduction by CO to elemental sulfur [10].
Therefore, with Cu content decreasing, the sample had sharper peaks and larger crystallite sizes, and a reduction of crystallite size from 10 nm for pure CeO2, to 6 nm with Cu/(Cu+Ce) molar ratio equal to 0.1.
Since we are trying to correlate the resistance change during sensing with the XRD and XPS data, it is Fig.4 Sensitivity curve of sensing element containing different CuO calcined at 1023K to 0.5% CO Fig.5 Dynamic response to 0.5% CO at 550K for sensing element CuO calcined at 1023K important to highlight the relationships between these measurements.
Therefore, with Cu content decreasing, the sample had sharper peaks and larger crystallite sizes, and a reduction of crystallite size from 10 nm for pure CeO2, to 6 nm with Cu/(Cu+Ce) molar ratio equal to 0.1.
Since we are trying to correlate the resistance change during sensing with the XRD and XPS data, it is Fig.4 Sensitivity curve of sensing element containing different CuO calcined at 1023K to 0.5% CO Fig.5 Dynamic response to 0.5% CO at 550K for sensing element CuO calcined at 1023K important to highlight the relationships between these measurements.
Online since: March 2007
Authors: Zuo Gui Zhang, Yoshimi Watanabe, Eiji Akiyama, Yasuyuki Katada, Kaneaki Tsuzaki
In this study, the data
are obtained from SEM photographs of low magnification (x200) and every value of volume
fraction is average of five different fields.
From 4 passes to 8 passes, the volume fractions of Si particles have a very slight reduction.
It is considered that some fine Si particles maybe dissolved into Al matrix and lead to reduction of volume fraction of Si particles during ECAP process [14, 18].
From 4 passes to 8 passes, the volume fractions of Si particles have a very slight reduction.
It is considered that some fine Si particles maybe dissolved into Al matrix and lead to reduction of volume fraction of Si particles during ECAP process [14, 18].
Online since: June 2004
Authors: Naoki Oyanagi, Shin Ichi Nishizawa, Takaya Ohno, Kazuo Arai, Tsutomu Yatsuo, Kenji Fukuda, Takaya Suzuki, Yasunori Tanaka
Neudeck et al. [14] suggested that a device including at least "one
elementary" screw dislocation exhibited 5-35 % reduction in breakdown voltage, but their result is
not consistent with ours.
Wahab et al. [15] suggested that it was the high density (>2000 cm-2) of screw dislocations that cuased the serious reduction of breakdown voltage in their large size (1.0 mmφ) 4H-SiC Schottky diode.
On the other hand, changes in ΔVFWD are never seen, even after 11 hours stress (data not shown here), in the diodes on the Lely and high-quality grown areas.
Wahab et al. [15] suggested that it was the high density (>2000 cm-2) of screw dislocations that cuased the serious reduction of breakdown voltage in their large size (1.0 mmφ) 4H-SiC Schottky diode.
On the other hand, changes in ΔVFWD are never seen, even after 11 hours stress (data not shown here), in the diodes on the Lely and high-quality grown areas.