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应用SUNLIGHT模型求算微起伏区太阳辐射值——以松嫩平原大安古河道区为例 被引量:6
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作者 王权 杨正宇 孙广友 《地理科学》 CSSCI CSCD 北大核心 1998年第6期542-548,共7页
SUNLIGHT模型充分考虑了地形要素对太阳辐射的影响,适用于计算小流域的太阳辐射并较精确地描述其在微起伏区的分布特性.利用SUNLIGHT模型,对松嫩平原大安古河道区太阳辐射的直射辐射和散射辐射进行了计算,并对该古河道区的太阳辐射能的... SUNLIGHT模型充分考虑了地形要素对太阳辐射的影响,适用于计算小流域的太阳辐射并较精确地描述其在微起伏区的分布特性.利用SUNLIGHT模型,对松嫩平原大安古河道区太阳辐射的直射辐射和散射辐射进行了计算,并对该古河道区的太阳辐射能的分布作出精确的描述,为土地潜力性评价提供基础. 展开更多
关键词 古河道区 太阳辐射 sunlight模型 古河道
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Photocatalytic degradation of Acid Blue 62 over CuO-SnO_2 nanocomposite photocatalyst under simulated sunlight 被引量:17
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作者 XIA Hui-li ZHUANG Hui-sheng ZHANG Tao XIAO Dong-chang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第9期1141-1145,共5页
The novel CuO-SnO2 nanocomposite oxide photocatalysts were prepared by simple co-precipitation method, and characterized by X- ray diffraction, transmission electron microscopy, N2 adsorption-desorption measurement an... The novel CuO-SnO2 nanocomposite oxide photocatalysts were prepared by simple co-precipitation method, and characterized by X- ray diffraction, transmission electron microscopy, N2 adsorption-desorption measurement and UV-Vis diffuse reflectance spectroscopy. The photocatalytic activities of CuO-SnO2, evaluated using the photodegradation of Acid Blue 62 as a probe reaction under the irradiation of Xenon light, were also found to be related to the calcination temperature and the molar ratio of Cu to Sn. The maximum photocatalytic activity of the CuO-SnO2 photocatalyst was observed to be calcined at 500~C for 3 h (the molar ratio of Cu to Sn was 1:1) due to the sample with good crystallization and high surface area. It also showed much higher photocatalytic activity in treatment dye wastewater under simulated sunlight irradiation compared to Degussa P25 TiO2. 展开更多
关键词 PHOTOCATALYSIS copper oxide tin dioxide Acid Blue 62 (AB62) simulated sunlight
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Photocatalytic activity of CuO towards HER in catalyst from oxalic acid solution under simulated sunlight irradiation 被引量:7
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作者 姚茂海 唐有根 +2 位作者 张丽 杨海华 阎建辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第10期1944-1949,共6页
CuO was synthesized by thermal decomposition of Cu(NO3)2·3H2O at various temperatures and characterized by powder X-ray diffractometry(XRD) as well as scanning electron microscopy(SEM).The effects of calcination ... CuO was synthesized by thermal decomposition of Cu(NO3)2·3H2O at various temperatures and characterized by powder X-ray diffractometry(XRD) as well as scanning electron microscopy(SEM).The effects of calcination temperature,category of sacrificial reagent,initial sacrificial reagent concentration,and Ag loading content on the photocatalytic activity of the as-obtained CuO sample were investigated.The results show that the as-obtained CuO exhibits high activity for photocatalysis of H2 evolution reaction(HER) in oxalic acid solution under simulated sunlight irradiation.The highest photocatalytic activity of the as-obtained CuO was achieved at the calcination temperature of 1000℃,and oxalic acid was used as the sacrificial reagent with the concentration 0.05 mol/L.H2 evolution rate is as high as 2.98 mmol/(h·g) with 2%(mass fraction) loaded Ag.The possible photocatalytic reaction mechanism on the CuO photocatalyst for HER in oxalic acid solution was also discussed. 展开更多
关键词 copper oxide (CuO) hydrogen evolution reaction (HER) photocatalytic activity oxalic acid simulated sunlight
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Effect of HITRAN Database Improvement on Retrievals of Atmospheric Carbon Dioxide from Reflected Sunlight Spectra in the 1.61-μm Spectral Window 被引量:1
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作者 戴铁 石广玉 张兴赢 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第2期227-235,共9页
A large number of experimental and theoretical investigations of carbon dioxide (CO 2 ) spectra have been conducted since the most recent update of the High-Resolution Transmission Molecular Absorption (HITRAN) da... A large number of experimental and theoretical investigations of carbon dioxide (CO 2 ) spectra have been conducted since the most recent update of the High-Resolution Transmission Molecular Absorption (HITRAN) database. To maintain optimal parameters, the HITRAN 2004 CO 2 line list has been completely replaced by HITRAN 2008 data in the near-infrared region from 4300 cm-1 to 7000 cm-1 . To examine the effect of this change on the retrieval of CO 2 vertical column data from reflected sunlight spectra in the 1.61-μm spectral window, synthetic measurements for a given atmospheric state and instrument setup were generated and compared using radiative transfer model with the line-transition parameters from the HITRAN 2004 and 2008 databases. Simulated retrievals were then performed based on the optimal estimation retrieval theory. The results show that large systematic errors in atmospheric CO 2 column retrievals were induced by the differences in the HITRAN laboratory line parameters in the 1.61-μm region. The retrieved CO 2 columns were underestimated by 10 ppm using the HITRAN 2004 data, and improvements resulting from the use of the improved HITRAN database were more pronounced at a higher spectral resolution. 展开更多
关键词 HITRAN database retrieval of CO 2 reflected sunlight spectra
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Preparation of BiOCl0.9I0.1/β-Bi2O3 composite for degradation of tetracycline hydrochloride under simulated sunlight 被引量:7
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作者 Xiong Ma Kaiyi Chen +5 位作者 Bin Niu Yan Li Lei Wang Jingwei Huang Houde She Qizhao Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第10期1535-1543,共9页
A novel and effective BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst was synthesized through a precipitation method. The structure, morphology, and optical properties of the samples were certified by X-ray diffraction, UV... A novel and effective BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst was synthesized through a precipitation method. The structure, morphology, and optical properties of the samples were certified by X-ray diffraction, UV-Vis diffuse reflectance, scanning electron microscopy, and X-ray photoelectron spectroscopic characterizations. Photocatalytic experiments demonstrated that the synthesized BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst exhibited excellent photocatalytic performance toward the degradation of tetracycline hydrochloride(TCH) under simulated sunlight. Furthermore, the TCH degradation rate of BiOCl0.9I0.1/15%β-Bi2O3 increased by 27.6% and 61.4% compared with those of the pure BiOCl0.9I0.1 and pure β-Bi2O3, respectively. Due to the multiple vacancies and valence states possessed by BiOCl0.9I0.1/x%β-Bi2O3, namely Bi5+, Bi(3-x)+, Bi5+–O, Bi3+–O, I- and I3-, the charge separation in photocatalysis reactions can be effectively promoted. The Mott-Schottky measurements indicate that the conduction band(CB) level of BiOCl0.9I0.1/15%β-Bi2O3 becomes more negative relative to that of BiOCl0.9I0.1, guaranteeing an advantageous effect on the redox ability of the photocatalyst. This study provides a new bright spot for the construction of high-performance photocatalysts. 展开更多
关键词 BiOCl0.9I0.1/β-Bi2O3 DEGRADATION Tetracycline hydrochloride PHOTOCATALYSIS Simulated sunlight
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Photocatalytic H_2 evolution activity of CuO/ZrO_2 composite catalyst under simulated sunlight irradiation 被引量:2
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作者 阎建辉 姚茂海 +2 位作者 张丽 唐有根 杨海华 《Journal of Central South University》 SCIE EI CAS 2011年第1期56-62,共7页
Zirconia-supported CuO (CuO/ZrO2) composite photocatalysts were successfully synthesized via citric acid-assisted sol-gel technique. For comparison, CuO/ZrO2 materials were also prepared by solid state reaction and ... Zirconia-supported CuO (CuO/ZrO2) composite photocatalysts were successfully synthesized via citric acid-assisted sol-gel technique. For comparison, CuO/ZrO2 materials were also prepared by solid state reaction and co-precipitation method. The as-prepared powders were characterized by X-ray diffractometry (XRD), transmission electron microscopy (TEM), and thermogravimetric-differential thermal analysis (TG-DTA). The photocatalytic activity of CuO/ZrO2 catalyst was investigated based on the H2 evolution from oxalic acid solution under simulated sunlight irradiation. The effects of molar ratio of CuO to ZrO2, preparation method, phase change with the calcination temperature and the durability on the photocatalytic activity of the photocatalyst were investigated in detail. It is found that the optimal activity of photocatalytic H2 evolution (2.41 mmol.h i.g-~) can be obtained when CuO/ZrO2 composite photocatalyst is synthesized by sol-gel technique and the mole ratio of CuO to ZrO2 is 40%. The activity of copper oxide supported on monoclinic ZrO2 calcined at higher temperature is much higher than that on tetragonal ZrO2 calcined at lower temperature, and the best calcination temperature is 900 ℃. 展开更多
关键词 CuO/ZrO2 photocatalytic activity hydrogen evolution simulated sunlight
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Effect of Sunlight Exposure and Different Withering Durations on Theanine Levels in Tea (<i>Camellia sinensis</i>) 被引量:1
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作者 Janet Chebet Too Thomas Kinyanjui +1 位作者 John Kanyiri Wanyoko Francis Nyamu Wachira 《Food and Nutrition Sciences》 2015年第11期1014-1021,共8页
Theanine is a non-protein amino acid representing as much as 50% of the total amino acids in black tea and 1% - 2% of dry weight in green tea. It has been shown to be able to reduce high blood pressure, promote relaxa... Theanine is a non-protein amino acid representing as much as 50% of the total amino acids in black tea and 1% - 2% of dry weight in green tea. It has been shown to be able to reduce high blood pressure, promote relaxation, and inhibit caffeine’s side effects among others. This current study explored the effects of sunlight and withering durations on theanine levels in tea shoots. Theanine content from three leaves and a bud, two leaves and a bud and internodes were detected and quantified by using High Performance Liquid chromatography (HPLC). Sunlight exposure experiment was started at dawn (0600 HRS, GMT + 3.00) when the light intensity was low and tea was collected at three-hour interval throughout the day to (1800 Hrs, GMT + 3.00) when the light intensity had dropped. At the start of the experiment, the theanine levels were significantly high but as the intensity of sunlight increased during the day there was a significant drop in theanine levels, and as the sun set the theanine levels increased significantly again in all samples. The results also showed that theanine levels were significantly increased after 15 hours of withering. Three leaves and a bud withered for 3 hours had mean theanine levels of 1.41% and those withered for 15 hours had mean theanine levels of 3.11%. Internodes exhibited higher mean theanine levels than those of leaves. In the light of these results, it’s evident that withering for a longer period of time and harvesting of tea when the light intensity is low ensure high amount of theanine in tea. 展开更多
关键词 Green TEA THEANINE WITHERING Time sunlight Exposure Health Benefits
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Changes in nutrient uptake of phytoplankton under the interaction between sunlight and phosphate in the Changjiang (Yangtze) River Estuary 被引量:4
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作者 FANG Tao LI Daoji YU Lihua LI Yun 《Chinese Journal Of Geochemistry》 EI CAS 2008年第2期161-170,共10页
We conducted ship-board incubation experiments to investigate changes in nutrient uptake of phytoplankton under different phosphate concentrations and irradiances in the Changjiang River Estuary and its adjacent water... We conducted ship-board incubation experiments to investigate changes in nutrient uptake of phytoplankton under different phosphate concentrations and irradiances in the Changjiang River Estuary and its adjacent waters in China. Under 100% natural irradiance the uptake rates of phosphate, silicate, and nitrate were accelerated at high phosphate levels (1.84 μM), while under low irradiance (about 50% natural irradiance) their uptake rates were restrained at the high but stimulated greatly at the intermediate phosphate concentrations (1.26 μM), as the growth of phytoplankton, changes in nitrite and ammonium uptake didn't follow an obvious pattern. Our results also showed that there were linear relationships between nitrate, silicate and phosphate uptake at different phosphate concentrations under low and high irradiances, and the growth period of phytoplankton was prolonged both at the high phosphate concentrations under high irradiance and at the intermediate concentrations under low irradiance, suggesting that the limitation of phytoplankton growth mainly reflected changes in its growth period, and because no such environment (low irradiance and low phosphate concentrations) actually existed in a high turbidity zone, phytoplankton blooms hardly occurred there. In the absence of irradiance, denitrification occurred readily and phytoplankton was kept decreasing, which resulted in phosphate regeneration. 展开更多
关键词 长江 日光 营养素 浮游植物
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Review on Effects of Sunlight on the Internal Quality of Peach Fruit 被引量:2
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作者 Zhisheng MA Yuehui WANG +2 位作者 Ruixia BAI Jianming LI Yunyun JIA 《Agricultural Biotechnology》 CAS 2021年第1期29-35,共7页
On the basis of referring plenty of literatures, we summed up the research advance in effects of sun light on the internal quality of peach fruit. This paper discussed the effect of light on the internal quality of pe... On the basis of referring plenty of literatures, we summed up the research advance in effects of sun light on the internal quality of peach fruit. This paper discussed the effect of light on the internal quality of peach fruit under the conditions of open cultivation, protected cultivation, bagging and surface covering with reflective film, the mechanism of occurrence and the technical measures to improve the utilization rate of light and light energy, and prospected the future research work. 展开更多
关键词 Peach tree sunlight FRUIT Soluble solid content Organic acid Vitamin C PROTEIN
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Analysis of Vitamin D Status in Men Highly Exposed to Sunlight 被引量:5
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作者 ZHANG Rong Hua HE Deng Hua +4 位作者 ZHOU Biao ZHU Yi Bo ZHAO Dong HUANG Li Chun DING Gang Qiang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第12期913-916,共4页
People living near the equator more easily obtain adequate 25-hydroxyvitamin D [25(OH)D]. However, studies indicated that vitamin D deficiency is common even in the sunniest areas. We mainly analyzed the vitamin D sta... People living near the equator more easily obtain adequate 25-hydroxyvitamin D [25(OH)D]. However, studies indicated that vitamin D deficiency is common even in the sunniest areas. We mainly analyzed the vitamin D status and dietary patterns of men highly exposed to sunlight, and investigated the correlation of vitamin D status with dietary patterns and time for outdoor work or activities. The average vitamin D levels among men highly exposed to sunlight was sufficient, but parts of the population had vitamin D deficiency or insufficiency. Long-term vitamin D deficiency may correlate with obesity and hypertension. These results provide a scientific basis for future research. 展开更多
关键词 Analysis of Vitamin D Status in Men Highly Exposed to sunlight
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Biological effects of indoor sunlight in ruraldweling houses
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作者 Chen Guifu , Qiu Shicong(Wannan Medical College , Wuhu 241001 , China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1995年第4期435-442,共8页
BiologicaleffectsofindoorsunlightinruraldwelinghousesChenGuifu,QiuShicong(WannanMedicalCollege,Wuhu241001,Ch... BiologicaleffectsofindoorsunlightinruraldwelinghousesChenGuifu,QiuShicong(WannanMedicalCollege,Wuhu241001,China)Biologicaleff... 展开更多
关键词 biological effect deactivation of bacteria immunological effect antirachitic effect sunlight.
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Formation of DNA Strand Breaks in Peripheral Lymphocytes of Rats After Exposure to Natural Sunlight
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作者 Dorival Mendes RODRIGUES-JUNIOR Ana Amélia de CARVALHO MELO +1 位作者 Benedito Borges da SILVA Pedro Vitor LOPES-COSTA 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2012年第2期245-249,共5页
Objective This paper aims to evaluate the genotoxicity in peripheral blood lymphocytes of rats after exposure to sunlight at different time points of day in a tropical region of Brazil(5oS,42oW).Materials and Method... Objective This paper aims to evaluate the genotoxicity in peripheral blood lymphocytes of rats after exposure to sunlight at different time points of day in a tropical region of Brazil(5oS,42oW).Materials and Methods Thirty Wistar-Hannover rats,three months old,were randomly divided into three groups of 10 animals each:Group I [control,without exposure to ultraviolet(UV) radiation],Group II(exposed to sunlight during 08:00 a.m.to 10:00 a.m.),and Group III(exposed to sunlight during 10:00 a.m.to 12:00 a.m.).After a week of exposure,peripheral blood samples were taken from the tail of these animals to prepare smears on two slides per animal.In 24 h after exposure to sunlight in Group III,a new collection was obtained to observe the repair activity.The alkaline comet assay was used in this study to evaluate the genotoxic activity of sunlight(P0.05).Results There was no statistical difference between Group I and II(P=0.672).On the other hand,the exposure to sunlight in Group III showed genotoxic action in comparison to the other groups(P0.0001).Also,there was no significant repair in Group III R(P=0.407).Conclusion This study has shown a genotoxic potential of sunlight(UVA-B) in lymphocytes of mammals from 10:00 a.m.to 12:00 a.m.,due to a higher intensity of UV in this tropical region. 展开更多
关键词 Comet assay DNA damage RATS sunlight Ultraviolet radiation
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Models to predict sunlight-induced photodegradation rates of contaminants in wastewater stabilisation ponds and clarifiers
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作者 Xi-Zhi Niu 《Water Science and Engineering》 EI CAS CSCD 2019年第4期293-297,共5页
Two kinetic models were established for conservative estimates of photodegradation rates of contaminants under sunlight irradiation,in particular for wastewater stabilisation ponds and clarifiers in conventional waste... Two kinetic models were established for conservative estimates of photodegradation rates of contaminants under sunlight irradiation,in particular for wastewater stabilisation ponds and clarifiers in conventional wastewater treatment plants.These two models were designated for(1)contaminants with high photolytic rates or high photolytic quantum yields,whose photodegradation is unlikely to be enhanced by aquatic photosensitisers;and(2)contaminants withstanding direct photolysis in sunlit waters but subjected to indirect photolysis.The effortlessly intelligible prediction procedure involves sampling and analysis of real water samples,simulated solar experiments in the laboratory,and transfer of the laboratory results to realise water treatment using the prediction models.Although similar models have been widely used for laboratory studies,this paper provides a preliminary example of translating laboratory results to the photochemical fate of contaminants in real waters. 展开更多
关键词 sunlight irradiation PHOTODEGRADATION CONTAMINANTS Stabilisation ponds Solar water treatment
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Sunlight loss for femtosecond microstructured silicon with two impurity bands
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作者 方健 陈长水 +1 位作者 王芳 刘颂豪 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第7期177-181,共5页
Black silicon, produced by irradiating the surface of a silicon wafer with femtosecond laser pulses in the presence of a sulfur-bearing gas, is widely believed to be a potential material for efficient multi-intermedia... Black silicon, produced by irradiating the surface of a silicon wafer with femtosecond laser pulses in the presence of a sulfur-bearing gas, is widely believed to be a potential material for efficient multi-intermediate-band silicon solar cells. Taking chalcogen as an example, we analyse the loss of sunlight for silicon with two impurity bands and we find that loss of the sunlight can be minimized to 0.332 when Te^0(0.307 eV) and Te+(0.411 eV) are doped into microstructured silicon. Finally, problems needed to be resolved in analysing the relationship between conversion efficiency of the ideal four-band silicon solar cell and the position of the introduced two intermediated bands in silicon according to detailed balance theory are pointed out with great emphasis. 展开更多
关键词 black silicon solar cell with impurity bands loss of sunlight
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Power Output Improvement of PV Module for Agricultural Use by Using Inexpensive Sunlight Concentrator
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作者 NISHIMURA Ryo 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第4期56-59,共4页
PV modules are used as stand alone power sources for agricultural equipments such as lifting pumps in farms, where the power infrastructure is not yet improved. In order to expand the agricultural use of PV module, th... PV modules are used as stand alone power sources for agricultural equipments such as lifting pumps in farms, where the power infrastructure is not yet improved. In order to expand the agricultural use of PV module, the cost of PV generation should be reduced. In this paper, the power output performance of a commercial PV module was improved by using a sunlight concentrator that could be assembled inexpensively and a simple sun-tracking method. 展开更多
关键词 photovoltaic module photovoltaic power generation sunlight concentration arid region cost reduction
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Studies on Forecast Model of Photosynthetic Active Radiation in Sunlight Greenhouse in Winter in Panjin
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作者 张美玲 陈龙 +2 位作者 辛明月 徐卓 李俊和 《Agricultural Science & Technology》 CAS 2015年第2期214-218,共5页
In order to explore the law of photosynthetic active radiation in winter sunlight greenhouse in Panjin and serve the local facility agriculture better,based on the observed data of sunlight greenhouse microclimate and... In order to explore the law of photosynthetic active radiation in winter sunlight greenhouse in Panjin and serve the local facility agriculture better,based on the observed data of sunlight greenhouse microclimate and of the nearby weather station during winter in 2012,the methods of correlation analysis and stepwise regression analysis were adopted to study characteristics of photosynthetic active radiation in sunlight greenhouse and the ratio of photosynthetic active radiation to global radiation under different weather types during winter,and to set up forecast models of photosynthetic active radiation in sunlight greenhouse under different weather types during winter.The results showed that:(1) the daily variation of photosynthetic active radiation in sunlight greenhouse on sunny and cloudy days were both obvious,and photosynthetic active radiation in sunlight greenhouse was 1-38 W/m^2 when it's cloudy.(2) ηPARon typical cloudy day was the highest,on cloudy day was secondary and on sunny day was the minimum during winter;(3) the methods of stepwise regression analysis were respectively adopted to set up models of the highest daily maximum photosynthetic active radiation,the total daily photosynthetic active radiation,daily maximum global radiation,and the total daily global radiation in sunlight greenhouse associated with climate outside,the models passed the 0.01 level of significance,and fitting test had been carried out:4 factors were fitted well on sunny and cloudy day,but fitted poor on overcast day. 展开更多
关键词 sunlight greenhouse Photosynthetic active radiation MODEL Panjin
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Effects of sunlight on tundra nitrous oxide and methane fluxes in maritime Antarctica
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作者 BAO Tao ZHU Renbin +1 位作者 YE Wenjuan XU Hua 《Advances in Polar Science》 CSCD 2020年第3期178-191,共14页
The relationships of nitrous oxide(N2O)and methane(CH4)emissions to other environmental parameters have been studied extensively in Antarctic terrestrial ecosystems.However,the effects of sunlight on soil N2O and CH4 ... The relationships of nitrous oxide(N2O)and methane(CH4)emissions to other environmental parameters have been studied extensively in Antarctic terrestrial ecosystems.However,the effects of sunlight on soil N2O and CH4 fluxes are neglected across the Antarctic tundra.Here,fluxes of N2O and CH4 from maritime Antarctic tundra soils were measured in the absence and presence of sunlight during three summers.The N2O fluxes averaged-4.6±1.2μg·m^-2·h^-1 in the absence of sunlight and 5.7±1.5μg·m^-2·h^-1 in its presence;CH4 fluxes averaged 119.8±24.5μg·m^-2·h^-1(absence)and-40.5±28.3μg·m^-2·h^-1(presence).The correlations between N2O and CH4 fluxes and other environmental variables(e.g.,soil moisture,temperature,organic and inorganic material)were not statistically significant(P>0.05)at all sites.On average,sunlight significantly increased N2O emissions and CH4 uptake by 10.3μg·m^-2·h^-1 and 160.3μg·m^-2·h^-1,respectively.This study indicates that sunlight is critical for accurately estimating N2O and CH4 budgets from maritime Antarctica and necessary for constraining the role of their emissions from tundra soil. 展开更多
关键词 sunlight METHANE nitrous oxide greenhouse gas soil WETLAND ANTARCTICA
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Photocatalytic Degradation of Acid Blue 62 over La/I/TiO2 Nanocomposite Photocatalyst under Simulated Sunlight
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作者 LI Ling ZHUANG Hui-sheng BU Dan 《Journal of Donghua University(English Edition)》 EI CAS 2010年第6期760-763,共4页
In order to explore the photocatalytic activity of the lanthanum and iodine co-doped TiO2,the degradation of acid blue 62 as a probe reaction under simulated sunlight irradiattion was investigated.A novel visible-ligh... In order to explore the photocatalytic activity of the lanthanum and iodine co-doped TiO2,the degradation of acid blue 62 as a probe reaction under simulated sunlight irradiattion was investigated.A novel visible-light-activated La/I/TiO2 nanocomposition photocatalyst was prepared using precipitation-diping method,and characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM)and UV-Vis diffuse reflectance spectroscopy(UV-Vis-DRS).The photocatalytic efficiency of La/I/TiO2 was evaluated by the photodegradation of reactive acid blue 62 as a probe reaction under simulated sunlight irradiationt.Photocatalytic experiment results shows that the La/I co-doped TiO2 catalyst has higher photocatalytic activity than the standard Degussa P25,La-doped TiO2 and I-doped TiO2 photocatalysts under simulated sunlight irradiation,and the way of La/I co-doping extends the absorption spectra of TiO2 and shifts the absorption edge remarkably toward longer wavelength. 展开更多
关键词 simulated sunlight PHOTOCATALYSIS titanium dioxide CO-DOPING acid blue 62(AB62)
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Intermediaries and Targets of the Oxidative Stress Induced by Natural Sunlight in Escherichia coil
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作者 Oscar J. Oppezzo 《Journal of Life Sciences》 2012年第2期130-136,共7页
The lethal effect produced by sunlight in bacteria depends on the photodynamic action of the ultraviolet component of the radiation. Neither the reactive oxygen species involved nor the targets for damage have been ce... The lethal effect produced by sunlight in bacteria depends on the photodynamic action of the ultraviolet component of the radiation. Neither the reactive oxygen species involved nor the targets for damage have been certainly identified, and the aim of this study was to address these issues. During exposures to natural sunlight, photo-protection provided by nitrogen sparging was compared with which provided by the addition of L-histidine (an efficient scavenger for hydroxyl radical and singlet oxygen) or mannitol (an hydroxyl radical scavenger which reacts poorly with singlet oxygen) to the irradiation medium. Both scavengers reproduced for the most part the effect of oxygen depletion, indicating that damage depends mainly on hydroxyl radical generation. Survival of irradiated bacteria decreased considerably when they were cultured using a substrate unsuitable for fermentation, suggesting that respiration impairment is a key factor in cell killing. This observation is in keeping with the notion that the respiratory chain is the main target for the action of sunlight in Escherichia coli. 展开更多
关键词 sunlight survival oxidative damage SCAVENGERS RESPIRATION Escherichia coll.
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Technology issues and prevention strategies on sunlight greenhouse vegetable
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作者 Junjie Hu 《International Journal of Technology Management》 2013年第10期18-20,共3页
Energy-saving solar greenhouse vegetables cultivating is to create and improve microclimate environment with greenhouse in those seasons impossible for open cultivation production and in order to achieve the purpose o... Energy-saving solar greenhouse vegetables cultivating is to create and improve microclimate environment with greenhouse in those seasons impossible for open cultivation production and in order to achieve the purpose of harvest in advance or in delay. Since a greenhouse needs huge construction expenses and high production costs, only though the improvement of facility utilization can we obtain better economic benefits. Vegetable germination and seedling stage need a long time for ground, so they need smaller standing area. So we concentrated in a small area of cultivation can not only create a suitable environment easily, nurture strong age seedling, but also can avoid greenhouse waste. Make transplanting to greenhouse after Seedlings breeding can effectively reduce the fertility cycle and substantially increase greenhouse utilization. 展开更多
关键词 sunlight greenhouse vegetable Vegetable cultivation Temperature Control.
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