In the last three decades much researchhas been carried out to investigate the biologicaleffects of a thinning stratospheric ozone layeraccompanied by an enhanced level of solarultraviolet-B radiation at the Earth’s ...In the last three decades much researchhas been carried out to investigate the biologicaleffects of a thinning stratospheric ozone layeraccompanied by an enhanced level of solarultraviolet-B radiation at the Earth’s surface.Enhanced UV-B radiation affects ecosystems in manyways directly and indirectly. The responses can bebiochemical, physiological, morphological oranatomical, and the direction of the response can varybetween different species, communities andecosystems. In this paper we firstly introduce generalconcepts, and methods for measuring the ecologicaleffects of UV-B radiation. Secondly, we provide anoverview interpretation of the effects of enhancedUV-B on terrestrial ecosystems from recent studies.These studies include effects of UV-B on growth andreproduction, composition of communities,competitive balance, decomposition of litter, andinteractions with other factors etc. Finally, werecommend future research directions to identify theeffects of elevated UV-B radiation on ecosystems inChina.展开更多
It has been more than half a century since the release of the first Shimadzu UV-VIS （UV-visible） spectrophotometer QB-50 in 1952, and during this time more than 160,000 UV-VIS spectrometers have been produced and in...It has been more than half a century since the release of the first Shimadzu UV-VIS （UV-visible） spectrophotometer QB-50 in 1952, and during this time more than 160,000 UV-VIS spectrometers have been produced and installed in a wide variety of different applications. A lot of technical innovations have been implemented to improve the performance and significantly reduce the stray light levels. The latest innovation during development of sophisticated spectrophotometers is based on a new holographic exposure method and optimized etching process which has made it possible to produce both high-efficient and exceptionally low stray light gratings. These LO-RAY-LIGH~ gratings have guaranteed values of stray light at the intermediate position between zero-order and first-order lights. The values are measured by Shimadzu＇s laser stray-light-measuring system. The latest development in the series of UV-VIS spectrophotometers is the UV-2700 which is a true double beam double monochromator system in a compact design for high-precision spectral analysis of a wide range of samples including organic and inorganic compounds, biological samples, optical materials and photovoltaics. The high performance optical system is designed with ＂LO-RAY-LIGH＂ diffraction gratings, featuring highest efficiency and exceptionally low stray light. The spectrophotometer operates in the wavelength range from 185 nm to 900 nm and allows highly sophisticated applications such as direct measurement of high density samples up to 8 absorbance units without dilution.展开更多
Fucoxanthin content of five brown seaweed species of East Java collected from Talango district （Madura sea-Jawa sea） namely Padina australis, Turbinaria conoides, Sargassum cinereum, Sargassum filipendula and Sargas...Fucoxanthin content of five brown seaweed species of East Java collected from Talango district （Madura sea-Jawa sea） namely Padina australis, Turbinaria conoides, Sargassum cinereum, Sargassum filipendula and Sargassum echinocarpum were determined and samples were collected using Global Positioning System （GPS）. Fucoxanthin from those samples was determined using Thin Layer Chromatography （TLC）, High Pressure Liquid Chromatography （HPLC） and Spectrophotometer UV-Vis and the results were then calculated using Seely equation. The pigments separation using HPLC gave a better result compared to TLC, and beside fucoxanthin otlher pigments namely chlorophyll and β carotene were also identified in these samples. Four points of sampling location were chosen using GPS and spot with coordinate positions observed were 113.94444° EL-7.08795° SA; 113.94231° EL-7.08913° SA. The results showed that fucoxanthin content were as follow： Padina australis 0.2674± 0.0046 mg/g; Turbinaria conoides 0.2134± 0.0100 mg/g; Sargassum filipendula 0.1957 ± 0.0173 mg/g; Sargassum cinereum 0.1640 ± 0.0092 mg/g and Sargassum echinocarpum 0.1576 ± 0.0001 mg/g. It can be concluded that Padina australis and Turbinaria conoides contain the most amount of fucoxanthin and it is possible to be cultivated as edible brown seaweed fucoxanthin resources.展开更多
Composite Bi@Bi2O3 microspheres have been synthesized via a microwave-assisted solvothermal route. The Bi@Bi2O3 microspheres had a narrow size distribution in the range 1.2-2.8 mm. Glucose was selected as the reductan...Composite Bi@Bi2O3 microspheres have been synthesized via a microwave-assisted solvothermal route. The Bi@Bi2O3 microspheres had a narrow size distribution in the range 1.2-2.8 mm. Glucose was selected as the reductant, BiCl3 as the bismuth source, and ethylene glycol （EG） as the solvent in the synthesis system. The as-synthesized sample was characterized by X-ray diffraction （XRD）, Raman spectroscopy, X-ray photoelectron spectroscopy （XPS）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, particle diameter distribution, energy dispersive X-ray spectroscopy （EDS）, ultraviolet-visible （UV-vis） spectroscopy, and photoluminescence （PL） spectroscopy. The photocatalytic activities of the Bi@Bi2O3 microspheres were evaluated by the photodegradation of rhodamine B （RhB） and methyl orange （MO） dyes under UV light irradiation. The degradation reached -96.6% for RhB and 100% for MO after 4 h reaction in the presence of the as-synthesized Bi@Bi2O3 microspheres.展开更多
基金the State Key Basic Research and Development Plan(G2000046802-05)the Chinese Academy of Sciencesfor Innovation Key Project(KSCX1-07-02-02)+1 种基金National Tackle-Key-Problem Project(2001BA606A-05-01) the"Western Light”Project of Chinese Academy of Sciences for Talent Plan.
文摘In the last three decades much researchhas been carried out to investigate the biologicaleffects of a thinning stratospheric ozone layeraccompanied by an enhanced level of solarultraviolet-B radiation at the Earth’s surface.Enhanced UV-B radiation affects ecosystems in manyways directly and indirectly. The responses can bebiochemical, physiological, morphological oranatomical, and the direction of the response can varybetween different species, communities andecosystems. In this paper we firstly introduce generalconcepts, and methods for measuring the ecologicaleffects of UV-B radiation. Secondly, we provide anoverview interpretation of the effects of enhancedUV-B on terrestrial ecosystems from recent studies.These studies include effects of UV-B on growth andreproduction, composition of communities,competitive balance, decomposition of litter, andinteractions with other factors etc. Finally, werecommend future research directions to identify theeffects of elevated UV-B radiation on ecosystems inChina.
文摘It has been more than half a century since the release of the first Shimadzu UV-VIS （UV-visible） spectrophotometer QB-50 in 1952, and during this time more than 160,000 UV-VIS spectrometers have been produced and installed in a wide variety of different applications. A lot of technical innovations have been implemented to improve the performance and significantly reduce the stray light levels. The latest innovation during development of sophisticated spectrophotometers is based on a new holographic exposure method and optimized etching process which has made it possible to produce both high-efficient and exceptionally low stray light gratings. These LO-RAY-LIGH~ gratings have guaranteed values of stray light at the intermediate position between zero-order and first-order lights. The values are measured by Shimadzu＇s laser stray-light-measuring system. The latest development in the series of UV-VIS spectrophotometers is the UV-2700 which is a true double beam double monochromator system in a compact design for high-precision spectral analysis of a wide range of samples including organic and inorganic compounds, biological samples, optical materials and photovoltaics. The high performance optical system is designed with ＂LO-RAY-LIGH＂ diffraction gratings, featuring highest efficiency and exceptionally low stray light. The spectrophotometer operates in the wavelength range from 185 nm to 900 nm and allows highly sophisticated applications such as direct measurement of high density samples up to 8 absorbance units without dilution.
文摘Fucoxanthin content of five brown seaweed species of East Java collected from Talango district （Madura sea-Jawa sea） namely Padina australis, Turbinaria conoides, Sargassum cinereum, Sargassum filipendula and Sargassum echinocarpum were determined and samples were collected using Global Positioning System （GPS）. Fucoxanthin from those samples was determined using Thin Layer Chromatography （TLC）, High Pressure Liquid Chromatography （HPLC） and Spectrophotometer UV-Vis and the results were then calculated using Seely equation. The pigments separation using HPLC gave a better result compared to TLC, and beside fucoxanthin otlher pigments namely chlorophyll and β carotene were also identified in these samples. Four points of sampling location were chosen using GPS and spot with coordinate positions observed were 113.94444° EL-7.08795° SA; 113.94231° EL-7.08913° SA. The results showed that fucoxanthin content were as follow： Padina australis 0.2674± 0.0046 mg/g; Turbinaria conoides 0.2134± 0.0100 mg/g; Sargassum filipendula 0.1957 ± 0.0173 mg/g; Sargassum cinereum 0.1640 ± 0.0092 mg/g and Sargassum echinocarpum 0.1576 ± 0.0001 mg/g. It can be concluded that Padina australis and Turbinaria conoides contain the most amount of fucoxanthin and it is possible to be cultivated as edible brown seaweed fucoxanthin resources.
基金The financial supports Science Foundation of from the National Natural China （Nos. 20921001 and20535020）, the Innovation Method Fund of China （No 20081885189）, and the National High Technology Research and Development Program of China （No. 2009AA03Z321） are acknowledged.
文摘Composite Bi@Bi2O3 microspheres have been synthesized via a microwave-assisted solvothermal route. The Bi@Bi2O3 microspheres had a narrow size distribution in the range 1.2-2.8 mm. Glucose was selected as the reductant, BiCl3 as the bismuth source, and ethylene glycol （EG） as the solvent in the synthesis system. The as-synthesized sample was characterized by X-ray diffraction （XRD）, Raman spectroscopy, X-ray photoelectron spectroscopy （XPS）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, particle diameter distribution, energy dispersive X-ray spectroscopy （EDS）, ultraviolet-visible （UV-vis） spectroscopy, and photoluminescence （PL） spectroscopy. The photocatalytic activities of the Bi@Bi2O3 microspheres were evaluated by the photodegradation of rhodamine B （RhB） and methyl orange （MO） dyes under UV light irradiation. The degradation reached -96.6% for RhB and 100% for MO after 4 h reaction in the presence of the as-synthesized Bi@Bi2O3 microspheres.
