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101.
Emissions of greenhouse gases such as CO2, CO, CH4 and NOX from fossil fuel use are implicated in climate change. The use of bioethanol is one means to reduce fossil fuel use and emissions of greenhouse gases. This study investigated research to produce ethanol from sugar beet and use as fuel in Turkey. The calculated demand for bioethanol amounted to some 220,000 m3 where a 5% ethanol mix in petrol was used. Turkey has the potential to produce 30 million ton of sugar beet, which is sufficient to meet the bioethanol demand. 相似文献
102.
This study is focused on the preparation, characterization and thermal properties of microencapsulated n-heptadecane with polymethylmethacrylate shell. The PMMA/heptadecane microcapsules were synthesized as novel solid–liquid microencapsulated phase change material (microPCMs) by emulsion polymerization method. The chemical and thermal characterization of the microPCMs were investigated using scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA). The diameters of microPCMs were found in the narrow range (0.14–0.40 μm) under the stirring speed of 2000 rpm. The spherical surfaces of microPCMs were smooth and compact. The DSC results show that microPCMs have good energy storage capacity. Thermal cycling test showed that the microPCMs have good thermal reliability with respect to the changes in their thermal properties after repeated 5000 thermal cycling. TGA analyses also indicated that the microPCMs degraded in three steps and have good thermal stability. Based on all results, it can be considered that the PMMA/heptadecane microcapsules as novel solid–liquid microPCMs have good energy storage potential. 相似文献
103.
A series of poly(styrene-co-p-stearoyl styrene) copolymers as novel polymeric solid–solid phase-change materials (SSPCMs) were synthesized by the modification of polystyrene with stearoyl chloride. The chemical structure and crystalline morphology of the synthesized copolymers were determined with Fourier transform infrared spectroscopy and polarized optical microscopy, respectively. The thermal energy storage properties and thermal stability of the SSPCMs were investigated with differential scanning calorimetry and thermogravimetric analysis, respectively. In addition, the thermal conductivity of the SSPCMs was measured with a thermal property analyzer. Moreover, thermal cycling tests showed that the copolymers had good thermal reliability and chemical stability after being subjected to 5000 heating/cooling cycles. The synthesized poly(styrene-co-stearoyl styrene) copolymers as novel SSPCMs have considerable potential for thermal energy storage and temperature-control applications. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
104.
105.
Ahmet Tekin Hassan Elwan Kenneth Pedrotti 《Analog Integrated Circuits and Signal Processing》2010,65(2):225-238
In this paper, a novel universal receiver baseband approach is introduced. The chain includes a post-mixer noise shaping blocker
pre-filter, a programmable-gain post mixer amplifier (PMA) with blocker suppression, a differential ramp-based novel linear-in-dB
variable gain amplifier and a Sallen–Key output buffer. The 1.2-V chain is implemented in a 65-nm CMOS process, occupying
a die area of 0.45 mm2. The total power consumption of the baseband chain is 11.5 mW. The device can be tuned across a bandwidth of 700-KHz to 5.2-MHz
with 20 kHz resolution and is tested for two distinct mobile-TV applications; integrated services digital broadcasting-terrestrial
ISDB-T (3-segment f
c = 700 kHz) and digital video broadcasting-terrestrial/handheld (DVB-T/H f
c = 3.8 MHz). The measured IIP3 of the whole chain for the adjacent blocker channel is 24.2 and 24 dBm for the ISDB-T and DVB-T/H
modes, respectively. The measured input-referred noise density is 10.5 nV/sqrtHz in DVB-T/H mode and 14.5 nV/sqrtHz in ISDB-T
mode. 相似文献
106.
Multirelational k-Anonymity 总被引:1,自引:0,他引:1
Nergiz Mehmet Ercan Clifton Christopher Nergiz Ahmet Erhan 《Knowledge and Data Engineering, IEEE Transactions on》2009,21(8):1104-1117
k-Anonymity protects privacy by ensuring that data cannot be linked to a single individual. In a k-anonymous data set, any identifying information occurs in at least k tuples. Much research has been done to modify a single-table data set to satisfy anonymity constraints. This paper extends the definitions of k-anonymity to multiple relations and shows that previously proposed methodologies either fail to protect privacy or overly reduce the utility of the data in a multiple relation setting. We also propose two new clustering algorithms to achieve multirelational anonymity. Experiments show the effectiveness of the approach in terms of utility and efficiency. 相似文献
107.
Seismic base isolation using low-cost Scrap Tire Pads (STP) 总被引:1,自引:0,他引:1
This paper focuses on the experimental studies conducted on the development of no-cost seismic base isolation pads using scrap
automobile tire pads (STP). The mechanical and dynamic properties of STP specimens made from different tire brands, with different
number of layers, and orientations are evaluated experimentally. The tests are conducted using (a) axial compression tests,
(b) lumped mass small displacement free vibration, and (c) large displacement (inclined plate and reverse-cyclic) static shear
tests. The results of these STP tests are compared among themselves and against a commercially available laminated rubber
bearing specimen. A general relationship has been proposed which formulates the stiffness differences between the two principal
directions of rectangular pads. The paper includes three hypothetical design applications for the use of STPs.
STPs are prepared by placing 18 cm × 20 cm cut tread sections layers of car tires on top each other. Larger size STPs can
also be formed by placing longer strips of tread sections (integer multiples of tread width) side by side in alternating direction
layers or using a woven structure. Test results have shown that the friction between tire layers is sufficient to keep layers
intact. Although STP application cannot eliminate foundation-basement structural requirements, it presents advantages such
as low-technology no-cost pad, weight reduction, ease of handling, simple shear stiffness adjustment by changing the number
of layers, and environmental benefits by recycling scrap tires. 相似文献
108.
The aims of the present study were to determine biochemical properties of honey samples and to discriminate pure and adulterated honey produced by the standard bee feeding method (control honey), the shaking method (pure blossom honey), and overfeeding (100 kg/colony syrup) with sucrose syrup (adulterated honey). The biochemical properties evaluated were moisture, ash, acidity, hydroxymethylfurfural (HMF), specific sugars (i.e. fructose, glucose, fructose–glucose, sucrose, and maltose), diastase activity, δ13C value (honey), δ13C value (protein), electrical conductivity, potassium, vitamin C, and proline. Fifteen honey samples were analyzed by discriminant analysis stepwise method. Proline, electrical conductivity and sucrose were found as discriminative characters of samples. Based on these three properties 100% of original group cases (samples) correctly classified in their real group. We found that the honey produced by feeding with 100 kg sucrose syrup per colony contained the sucrose as low as pure blossom honey. Therefore, the sugar (sucrose, fructose and glucose) content of honey cannot be used to distinguish between adulterated (sucrose syrup) and pure blossom honey. 相似文献
109.
Cold season heating energy requirements in buildings can be estimated with the degree-hours method based on human comfort levels and available meteorological temperature records for a given area. Such estimations are especially significant for cities where fossil fuel consumption must be eliminated in favor of clean energy alternatives to reduce air pollution. This paper considers the city of Istanbul in Turkey and presents a detailed account for practical energy requirements and fuel consumption calculations. 相似文献
110.
Gross-α and gross-β, activities of eight well and five tap water samples taken in
stanbul were determined. Ra226, Rn222, Pb214, Bi214, K40, Cs137 activity concentrations in four lake, four sea water, one snow and one rain water samples were also analyzed in order to determine their radioactivity. The results obtained showed that, in general, natural activities in drinking water samples did not exceed WHO and ITS guidelines. In sea and lake water, four samples were over WHO and TSI guidelines. Concentrations ranging from 0.007 to 0.04 Bq l−1 and from 0.02 to 0.1 Bq l−1 were observed for drinking water and the gross-α and gross-β activities, respectively. For all samples the gross-β activities were higher than the corresponding gross-α activities. In order to evaluate the annual effective dose equilavent of ingestion of these waters, a conservative dosimetric calculation was carried out using dose conversion factor suggested by the ICRP. An average annual effective dose equivalent of 0.84 μSv y−1 for Ra226 was calculated. 相似文献