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An Assessment Study of Automotive Engine Carbon Removal TechnologyChiu, Ting-Cheng 17 July 2010 (has links)
Human large-scale use of coal, oil, natural gas and other fossil fuels, which emit large quantities of energy use is caused by the greenhouse effect of greenhouse gases, including carbon dioxide increases rapidly, is the culprit of global warming. Man type and species of global warming has brought the threat of the living environment, how to effectively slow down global warming has become the man to face critical issues. According to Taiwan's greenhouse gas emissions from all sectors data show that the transport sector with a significant contribution to greenhouse gas emissions, developed with the vehicle industry, motor vehicles have become the main transport means of transport to daily life, but also resulted in major metropolitan areas and air pollution from carbon dioxide, improve air quality and reduce carbon emissions, should have to be propaganda vehicle maintenance and regular inspection of work, vehicle maintenance facilities for the engine than coke will effectively reduce unnecessary vehicle emissions and pollution, with a view to sustainable human development.
This study to collect relevant information through expert interviews, sorting out the market viability of the Automotive engine carbon removal methods are "bubble-type engine than coke," the "trickle engine program than coke" and "In addition to product hydrogen aircraft engine Carbon Programme "of three. And to identify factors that impact assessment, "the cost of implementation", "when applied to pollution assessment," "clear the effect of coke", "engine damage effects" and "ease of handling," and five. Main and analytic theory, experts in the field to conduct the carbon removal of the vehicle engine is assessed for the valid questionnaires, the use of AHP Analysis Method Comparison of the order of priority or importance, to find consistency through the whole management of the common point of view.
Comprehensive management and access to the whole study found that industry, government, science and other 12 experts were assessing the overall level of the importance of the five ranking for the "impact of engine damage," the most important, were "clear the effect of coke," " when applied to pollution assessment, "" implementation costs "," easy operation "of the last. The engine in the current market feasible than carbon technology, the experts unanimously agree that the "hydrogen aircraft engine program than coke," the most advantage of the actual promotion of environmental protection that, the Government Ying Ying Zao Leung good conduct political Peihehuanjing, provide economic incentives to encourage people to Automotive engine carbon removal and counseling industry to promote environmental protection measures. The research results could serve as references for the Government's future vehicles and the carbon reduction policies.
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Fabrication of mDMFC and Effect of Methanol Modification on its PerformanceLu, Chang-Wei 21 August 2012 (has links)
Direct methanol fuel cell (DMFC) were characterized with low operation temperature, high energy density, rapid activation, easy to obtain, easy to carry, safety, stability and low pollution. Therefore, DMFCs were thought as the next generation of power suppliers to replace lithium battery in the future. In order to meet the miniaturization demand of portable electronic devices, this research tried to fabricate a £gDMFC, simplify component, and lower cost by using MEMS technique. This research used TMAH etching, PEACE, and KOH etching, CNT growth technique to fabricate the hill-like diffusion layer (HDL) electrode which combined the channel structure and through-hole silicon (THS) electrode.
Another emphasis of this research was to improve the bubble cover problem for £gDMFCs. The bubble cover problem resulted from the CO2 bubble generated in methanol oxidation reaction difficultly removed and resulted in adverse effect for reaction. This research tried to use the surfactants which used in electroforming to improve the bubble cover problem by improvement surface tension of fuel.
Experiments show that using the HDL electrode in anode and the THS electrode in cathode would get the maximum power density (0.186 mW/cm2). The powder density of the design £gDMFC is 10 and 2.5 times larger than the one with pure carbon paper electrodes and the HDL electrodes. Surfactant MA was suitable as a wetting of methanol. Bubble size could reduce 1/2 to 1/3 and bubble cover area could reduce 20% by adding MA. Add MA in the fuel cell could help the bubbles remove to avoid the bubble cover problem. Though MA addition would have the adverse effect for methanol reaction, could get the stabile voltage and extend the discharge time.
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Effects of Rainfall and Polysilicon Industrial Pretreated Effluent on Biological Nitrogen RemovalLu, Yi-chieh 04 September 2012 (has links)
The biological treatment is one of the commonly methods of wastewater treatment plant in wastewater treatment processes. The biological treatment can meet water quality standards required by the plant in response to different sewage conditions and qualities. It can purify high pollution loading sewage through the use of microbial metabolic transformation. Through effectively protecting and using water resources, the ecological balance of ocean and river can be maintained and environmental quality can be improved in consequence.
This study analyzes the operations of a wastewater treatment plant, which is part of an urban sewage system. The major sources of inflow to the plant are domestic sewage, followed by rainfall runoff and industrial wastewater. The biological treatment system adopted in the plant is "Biological Nutrient Removal (BNR)". The reason for using BNR is to prevent eutrophication of downstream water bodies due to untreated nitrogen, phosphorus and other nutrient substances in discharged sewages. The design of BNR, which is called "A2O activated sludge method", would increase the anaerobic-anaerobic mixing process for simultaneous removal of the sewage of organic carbon, nitrogen, phosphorus and BOD.
The study collected the data to analyze the impacts of extreme weather event, i.e. Typhoon Morakot, and the effects of newly developed industrial, i.e. polysilicon industry. Water quality data of inflow and outflow sewages starting from January 2009 to December 2011 were compiled to perform statistical analyses. By plotting various time series figures, the study can effectively explore the variations of pollutant removal under the two designated situations in the biological treatment system.
The results show the abnormal increase in conductivity of effluent which has decreased pollutant removal since August 2010. Besides, the confluence of rainwater and sewage has severely affected the efficiency and quality of the biological treatment process during a typhoon or heavy rain event. This study has identified the potential impacts on a BNR plant which can provide the administration to enhance the effectiveness of the biological treatment plant and the function of sewage purification stability control.
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Control of new follicular wave emergence and rate of follicular maturation in bos indicus-influenced cattle with estradiol benzoate, temporary calf removal and progesteronePack, Julie Diane 15 May 2009 (has links)
Objectives were to determine: 1) whether estradiol benzoate (EB) provides a superior alternative to GnRH for synchronizing emergence, growth and maturation of a new follicular wave for fixed timed AI (TAI) in Bos indicus-influenced cattle using CIDR-based protocols, 2) the effect of 48 h calf removal at CIDR removal on the rate of maturational synchrony of the dominant follicle and 3) the effect of varying the magnitude of peak plasma progesterone (P4) concentrations following CIDR insertion on the suppression of FSH and LH secretion in a CIDR-based protocol using EB. In experiment 1, sixty-four Braford (F-1) females were stratified by BCS, parity and days postpartum and assigned randomly to one of four groups in a 2 x 2 factorial arrangement of treatments: 1) Select-Synch + CIDR, 2) Select-Synch + CIDR with 48 h calf removal, 3) E-Synch + CIDR or 4) E-Synch + CIDR with 48 h calf removal. A greater number of cattle in the EB treated group exhibited NFWE compared to the GnRH group, 29 vs 17 cows for EB and GnRH respectively, (P<0.0006). Intervals to NFWE were also greater in EB treated cattle than in GnRH treated cattle, 4.2 vs 2.7 d for EB and GnRH treated cattle respectively, (P<0.0001). Proportions of GnRH- and EB-treated cows ovulating after CIDR removal did not differ. Post-CIDR suckling status did not affect ovulation frequency or interval to ovulation. In experiment 2, eight pubertal (F-1) heifers were used in a Latin Square design with four treatment levels of P4: 1) EB only, 2) EB and new CIDR, 3) EB and new autoclaved CIDR, 4) EB, new autoclaved CIDR and P4 injection at CIDR insertion. Treatments 2 through 4 increased (P < 0.01) mean plasma P4 concentrations compared to treatment 1, with treatment 4 creating the greatest increase in P4 with the longest duration. Suppression of plasma FSH was greatest in group 4 (P<0.08), with mean 60 h concentrations less than in all other groups. Mean concentrations of LH were lesser in group 4 than groups 1 and 2. Frequencies of occurrence of NFWE and ovulation and intervals to NFWE did not differ among treatments. Results indicate that the use of EB and CIDR to synchronize Brahman x Hereford females may provide better synchronization for TAI compared to GnRH and CIDR based protocols.
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Long-Term Hydrologic Responses To Shrub Removal In A SW Texas Rangeland: Using Soil Chloride To Estimate Deep DrainageBarre, David Anthony 2009 August 1900 (has links)
The Carrizo-Wilcox aquifer is a valuable groundwater resource, situated in a semi-arid
landscape of Southwest Texas, where over-use by dependent farming practices has
lowered aquifer levels. In semi-arid regions, rates of groundwater recharge are
predominantly low due to high potential evapotranspiration rates; however, least
understood is the role that vegetation plays in soil-plant-water dynamics. Vegetation
management potentially plays a major role in countering the loss to recharge because
evapotranspiration (ET) varies with vegetation type and cover. The conversion from
shrubland to grassland likely reduces rooting depths and total plant cover. Subsequently,
deep drainage (percolation below the root zone) will likely increase and lead to
groundwater recharge, at least temporarily. The primary aims of the study were to
identify those biotic and abiotic factors facilitating deep drainage and to examine
differences in recharge for the years following clearing of natural shrub vegetation. Soil
chloride was examined to estimate long-term recharge rates, since its concentration in
the soil is influenced by the movement of water. Short-term soil moisture trends were
also monitored for any water movement deep in the soil profile in response to individual rain events. Rooting depths decreased following removal of vegetation; yet root biomass
unexpectedly increased due to successful grass establishment during the first five years
after treatment. Soil properties did not vary between treatments, indicating that the
majority of chloride differences seen were a consequence of vegetation change. Peak
and total soil chloride concentrations were expected to decrease and occur deeper in the
soil profile 15-30 years following the clearing of woody vegetation. Total chloride
decreased by up to 65% after 30 years and resulted in an estimated 14.9 mm/yr more
recharge compared to adjacent untreated controls. Evidence in this study suggest that
much of this chloride is leached during the first five years following treatment and that
more leaching occurs in especially wet periods. During the wet 2007 growing season,
soil moisture below the root zone increased by up to 17% after vegetation clearing. The
results of this study indicate that hydrologic changes following brush removal were
evident in this system and are likely to positively influence groundwater recharge in the
long-term.
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Study on the Treatment of Sewage by A Combined Upflow Anaerobic Sludge Blanket (UASB) Constructed Wetland ProcessMa, Chia-Chen 12 July 2005 (has links)
Upflow anaerobic sludge blanket (UASB) has been developed and commercially used for treating high-strength wastewaters since 1971, and this process has been extended its applications to domestic sewage treatment since 1980.
Constructed wetlands (CWL) can be treated as a simulated natural treatment system, which use solar radiation as the energy source. By analogy with some removal mechanisms in natural wetlands, constructed wetlands are able to transform and remove pollutants from the wastewater. Other features provided by the constructed wetland include wildlife support, hydrologic modification, erosion protection, and open space and aesthetics. It has been applied for domestic wastewater purification for decades.
In this study, a pilot UASB-CWL reactor was built to test its performance for the removal of organic compounds and nutrients from a sewage with COD (Chemical oxygen demand) in the range of 200-300 mg/L. The UASB reactor has an active liquid volume of 2.5 liters and the CWL includes a 56 L-tank (CWL-1) followed by a 80 L-tank (CWL-2) in which emergent macrophyte (reed, Phragmites australis L.) and floating macrophyte (Pistia stratiotes L.), respectively, were planted. Effects of hydraulic retention time (HRT) of the test water in the reactor on the pollutant removal were tested.
Results indicate that with HRTs of 2, 45, and 64 hours, respectively, in the UASB, CWL-1, and CWL-2, the system exhibited good performances for pollutant removal. The HRTs are equivalent to CODt loadings of 3.06, 0.065, and 0.026 kg/m3.day to the UASB, CWL-1, and CWL-2, respectively. Average total COD (CODt), soluble COD (CODs), total biochemical oxygen demand (BODt), suspended solids (SS), and phosphate-P (P) were 121, 62, 33, 130, and 0.10 mg/L, respectively, and these are equivalent to the removal efficacies of 45-65, 60-80,65-75, 30-50, and 85-95%, respectively. With the operation conditions, average CODt = 28 , CODs = 18, BODt = 10, SS = 18, NH3-N = 18, NO2--N =12 , NO3--N = 1.0, and P = 0.0 mg/L were obtained, and the average removal total efficacies were 93, 93, 90, 75, 72, 95, and 100%, respectively. Effluent qualities are far superior to the national effluent standards for domestic sewage in Taiwan.
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Lead(ii) And Ammonium Exchange On Na Form Of Gordes ClinoptiloliteSedat, Asiroglu 01 September 2006 (has links) (PDF)
ABSTRACT
LEAD(II) AND AMMONIUM EXCHANGE on Na-FORM of GÖ / RDES CLINOPTILOLITE
ASiroglu, Sedat
M.S., Department of Chemical Engineering Supervisor Prof. Dr. Hayrettin Yü / cel
September 2006, 89 pages
Natural zeolites, especially clinoptilolite, have the ability of removing certain cations from wastewater by utilizing ion exchange and adsorption. In this study, ion exchange behaviour of Gö / rdes clinoptilolite at particle size range (0.5-0.25 mm) for lead and ammonium removal was investigated to establish the conditions under which clinoptilolite may be used in an economical and effective manner. Experiments were divided into two parts. Batch and continuous (column) experiments were carried out.
In the batch experiments, experimental isotherms of NH4+-Na+, Pb2+-Na+ binary systems and NH4+-Pb2+-Na+ ternary system were obtained as the graphs of equivalent fractions of exchanging cation in solution versus equivalent fractions of cation in zeolite. It was determined that clinoptilolite has affinity for Pb2+ and NH4+ ions. Finally, the selectivity sequence of Gö / rdes clinoptilolite in the presence of Pb2+ and NH4+ together was determined as Pb2+ > / NH4+ > / Na+.
In the column studies, removal of lead, ammonium and simultaneous removal of lead-ammonium solutions were investigated. The loading flow rates were selected as 8, 15, and 30 mL/min. The ion exchange capacity of clinoptilolite for lead and ammonium removal showed good performance. Flow rates at 8, 15, 30 mL/min, breakthrough capacities were found as 0.398 meq/g (Pb2+) and 0.337 meq/g (NH4+), 0.299 meq/g (Pb2+) and 0.297 meq/g (NH4+), 0.197 meq/g (Pb2+) and 0.198 meq/g (NH4+) for lead-ammonium-sodium system and corresponding column efficiencies were 63.36%, 51.38%, 34.05%, respectively.
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Multicomponent Ion Exchange On ClinoptiloliteBayraktaroglu, Kerem 01 September 2006 (has links) (PDF)
Zeolites are crystalline, hydrated aluminosilicate minerals that are characterized by their
ability to exchange some of their constituent cations with cations in aqueous solutions,
without a major change in their crystalline structure. Clinoptilolite is the most abundant ype of zeolite and it has received extensive attention due to its favorable selectivity for mmonium and certain heavy metal cations.
The aim of this study is to investigate the binary and ternary (multicomponent) ion xchange behavior of sodium form of Gö / rdes type clinoptilolite for ammonium,cadmium and sodium ions.
For this purpose, NH4
+-Na+,Cd2+-Na+ binary systems and NH4
+-Cd2+-Na+
multicomponent system were investigated both in batch and column systems at 0.1 and
0.01 constant total normality respectively and at 250C constant temperature. As a result
of binary and ternary experiments, clinoptilolite&rsquo / s affinity for both ions but greater
affinity to NH4+ ion than Cd2+ ion was observed and the selectivity sequence of Gö / rdes clinoptilolite was determined as NH4+> / Cd2+> / Na+ in binary and multicomponent batch
and column operations.
Additionally, total ion exchange capacities and maximum exchange levels of Gö / rdes
clinoptilolite for both ions were determined in batch systems whereas breakthrough
capacities and column efficiencies (for three different flow rates) were determined in column systems. Finally, it was concluded that the increase of the flow rate reduced the
breakthrough capacities and column efficiencies of Gö / rdes clinoptilolite for ammonium and cadmium ions in multicomponent column systems involving more than one cation.
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The Study in Degradation of Ammonia with MnO2 as Catalyst for WaterChen, Chi-Ting 25 July 2003 (has links)
Nitrogen oxide in water was a critical factor of eutrophication. The poor tap-water quality in Taiwan was the result of ammonia nitrogen pollution. This research used manganese dioxide as the catalyst to degrade ammonia nitrogen content in water. Controlled factors in our experiment include basic test, optimal reaction condition test, and kinetics. Real water sample was drawn from the Love River for catalysis effect test. Results were then compared with the popularly used titanium dioxide.
Significant findings in this research include: 1) when the manganese dioxide content in water was 2%, the ammonia nitrogen removal rates were 31.80% under UV irradiation, and 22.21 % without light interference; 2) under UV irradiation, manganese dioxide would not affect the catalysis effect due to pH changes; 3) silicate in the water had catalysis effect, while sulfate, phosphate, and nitrate had inhibition effect; 4) manganese dioxide had catalysis effect in seawater, yet the removal rate would decrease as the salt content increases; 5) the rise of water temperature would enhance the ammonia nitrogen removal rate; 6) manganese dioxide had catalysis effect on the treatment of the Love River water, and the ammonia nitrogen removal rate reached 89.50 %; 7) in the biological test, manganese dioxide could effectively degrade the ammonia nitrogen content in water, and improve the survival rate of larval shrimp; 8) comparing to titanium dioxide, manganese dioxide had advantages of low cost, with catalysis effect in both seawater and fresh water under no light condition. As a result, manganese dioxide has significant future application potentials.
In the future, this research will conduct in-depth study on kinetics of degradability of manganese dioxide catalysis on ammonia nitrogen, and to design suitable catalytic reactor for water treatment. Moreover, it is of value to broadly research manganese dioxide related catalytic products, such as catalytic spray, catalytic paint, fluorescent tube, air filter, and catalytic fan...etc.
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Removing Noise from Signals via Neural NetworksZheng, Xiang-Ren 01 August 2003 (has links)
The main objective of this paper is to develop a method of removing noise from signal. This method is based on the radial-basis function networks and the principle of cross-validation in statistics. In this method, we detect noise by estimating the magnitude of validation error after training the network. Besides, this paper applies the concept of predictive coding to select data set from image when the proposed method used to deal with the noise removal problem of two-dimensional image signals. Finally, the proposed method has been employed to deal with noise removal problems of one-dimensional and two-dimensional signals. From the result of simulation, the proposed method could remove noise from signals effectively.
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