GENERATION OF SYNTHETIC AND MISSING CLIMATIC DATA FOR PUERTO RICO1

ABSTRACT: Climatic data such as temperature, solar radiation, relative humidity, and wind speed have been widely used to estimate evapotranspiration. Moat of the solar radiation data and portions of the relative humidity data are either not available or missing from the records in Puerto Rico. Depending upon the availability and data characteristics of records, three methods (including a regression technique, an averaging of historical data, and a regional average) were used to generate missing data, and a time series analysis was used to synthesize a series of climatic data. The limitations and applicability of each method are discussed. The results showed that the time series analysis method can be successfully used to synthesize a series of monthly solar radiations for several stations. The regression technique and the regional average can be successfully applied to generate missing monthly solar radiation data. The regression technique and the averaging of historical data have been satisfactorily used to interpolate missing monthly relative humidity. The explained variance (R²) varied from 0.68 to 0.88, which are both significant at the 0.05 level of significance.     

On the plausible association between environmental conditions and human eye damage

The increase in solar ultraviolet radiation can have various direct and indirect effects on human health, like the incidence of ocular damage. Data of eye damage in residents of three suburban regions in Greece and in two groups of monks/nuns and fishermen are examined here. The statistics performed on these data provides new information about the plausible association between increased levels of solar ultraviolet radiation, air-pollution at ground level, and the development of ocular defects.     

荔枝的光合特性

对糯米糍荔枝光合特性的研究结果表明，年平均蒸腾速率为８９３ｇＨ２Ｏ·ｍ－２·ｄ－１，净光合速率为６．５９ｇＣＯ２·ｍ－２·ｄ－１，蒸腾系数为２０２．２５ｇＨ２Ｏ·ｇＤＭ－１，对光合有效辐射能的利用率为１．９５％，说明了荔枝的光合性能和生产潜力。     

Thermal analysis of tilted wick solar distillation-cum-drying system

The performance of the designed tilted wick solar water distillation-cum-drying unit has been tested at water flow rates of 50 and 65 ml/min in the distillation unit. Effect of water flow rates on the heat transfer coefficients of distillation and drying unit for drying ginger has been evaluated. The energy and exergy efficiency of the distillation system have also been evaluated. Average distillates of 2.36 and 2.2 l/m² were collected from the tilted wick solar still at flow rates of 50 and 65 ml/min, respectively. Large variation in convective and evaporative heat transfer coefficients of distillation unit has been observed at given water flow rates. Water flow rate in the distillation unit significantly affects the performance of the drying unit. Average convective heat transfer coefficients of 6.56 and 3.75 W/m^{2 o}C have been observed for drying ginger at flow rates of 50 and 65 ml/min, respectively. Energy and exergy efficiency of the distillation unit have been found to be nearly 19% and 0.9%, respectively. Experimental uncertainty has also been evaluated for distillation and drying units. The distillate cost for the developed distillation-cum-drying unit is calculated as $0.03729/l along with dried ginger of about 2.5 kg/m²/day.     

Thermal energy storage and thermodynamic properties of (E)-3-m-tolylbut-2-enoic acid as a medium temperature phase change material

Phase change materials (PCMs) that can store and release heat energy over the temperature range from 363 to 393 K are crucial for solar absorption cooling, and it is worthy to seek new solid-liquid PCMs candidates that melt and crystallize in this temperature range. In this paper, (E)-3-m-tolylbut-2-enoic acid (mTBEA) was applied as a PCM candidate. Its thermal energy storage properties and thermal stability were systematically investigated. The results showed that mTBEA melted at 382.9 ± 0.5 K and crystallized at about 364 K, with a melting enthalpy (Δ_fusH) of 138.4 ± 6.9 J g^?1 and showed good long-term cyclic stability and thermal stability. The supercooling of mTBEA was stabilized at about 20 K, indicating that the conservation condition of melted mTBEA could be simple. In addition, the melted mTBEA could release all the absorbed thermal energy upon crystallizing. Besides, mTBEA exhibited good thermal stability for it to be applied as PCM. Hence, mTBEA is a promising PCM candidate for solar absorption cooling. Furthermore, the heat capacity of mTBEA was measured by modulated temperature differential scanning calorimetry (MTDSC) over the temperature range from 198.15 to 431.15 K, and the molar thermodynamic functions, [H_T-H_298.15]_m and [S_T-S_298.15]_m, were calculated based on the fitted molar heat capacity data.     

A solar hybrid thermoelectric generator and distillation system

A solar still of a single basin-slope coupled with a finned condensing chamber and installed thermoelectric modules at the bottom of the water basin has been presented in this paper. A mathematical model under steady state conditions has been introduced and improved to investigate the system performance. An increase of solar radiation and ambient temperature or a decrease in wind velocity affect positively the distillation rate, the still efficiency, and the system efficiency. Integrating a condenser and finned condenser increases the distillation rate of the proposed system. The results of the simulation have been verified by comparing them with published theoretical and experimental results, and the comparison shows very good agreement.     

上海气象参数与太阳活动和ENSO的关系

运用2进小波的分解与重构技术分析了太阳活动、厄尔尼诺—南方涛动(ENS0)与上海地区月降水量、月均气压和月均温度序列之间的可能关系。研究结果表明，在不同的时间尺度(频带)上太阳活动和ENS0对上海的月降水量、月均气压和月均温度有不同的影响；在某种程度上ENS0活动对上海月降水量和月均气温的影响强于太阳活动的影响。结果还清楚表明和证实了在不同频带上太阳活动与ENS0活动之间的密切联系。     

Performance analysis of different orc power plant configurations using solar and geothermal heat sources

ABSTRACT

Energy optimization is performed on hybrid solar-geothermal power plant working according to Organic Rankine Cycle and installed in southern Tunisia. The performances of four different configurations of the power plant are studied. Mass and energy balances are established for the different compounds. The effects of the main operating parameters such as the geothermal water temperature, ambient temperature and direct normal irradiation on the power plant performances are analyzed. A code is established using Engineering Equation Solver software (EES) to perform the required calculations. Obtained results show that the hybrid solar-geothermal power plant with a heat recovery system is the most suitable configuration design giving a better overall energy efficiency of 15.77 and13.11% and a maximum net power of 1089 and 1882 kW in winter and summer, respectively. However, in the summer season, using a heat recovery system can valuable only when the water temperature is higher than 66°C. For air-cooled condenser, the suitable condensing pressure is 1 bar in winter and 1.9 bars in summer.     

连城太阳能光伏产业发展现状与战略选择

太阳能光伏产业是21世纪备受世界各国重视的高新技术产业之一,拥有广阔发展前景,基于对太阳能光伏产业链、国内太阳能光伏产业现状的分析及连城太阳能光伏产业现状与面临挑战的分析,提出连城太阳能光伏产业发展战略。     

Degradation of Reactive Yellow 86 with photo-Fenton process driven by solar light

The decolorization of Reactive Yellow 86(RY 86),one of reactive azo dyes,was investigated in the presence of Fenton reagent under solar light irradiation.The decolorization rate was strongly influenced by pH,initial concentrations of H 2 O 2 and Fe(II),and so on.An initial concentration of 40 mg/L was decolored more than 90% after 20 min under optimum conditions.The activation energy of the solar photo-Fenton reaction was 1.50 kJ/mol for RY 86 in the temperature range of 10-60°C.In the kinetic study,the rate constant of RY 86 with OH· radicals could be estimated to be 1.7 × 10 10 L/(mol·sec).The decolorization efficiency of RY 86 under solar light irradiation was comparable to the artificial light irradiation.The decrease of TOC as a result of mineralization of RY 86 was observed during photo-Fenton process.The rate of RY 86 mineralization was about 83% under UV irradiation after 24 hr.The formation of chloride,sulfate,nitrate and ammonium ions as end-products was observed during the photocatalytic process.The decomposition of RY 86 gave two kinds of intermediate products.The degradation mechanism of RY 86 was proposed on the base of the identified intermediates.