基于宽带网的河南省太阳紫外线强度监测系统研究

使用自主研发的Gstar-Ⅱ型太阳紫外线监测仪,建立基于宽带网的河南省城市紫外线强度监测系统。太阳紫外线强度自动监测站将从紫外线传感器获得的气象要素信息传给本地专用计算机,进行数据处理和编码,然后通过互联网把数据信息送到数据业务中心站,数据业务中心站具有对接收数据进行初步处理和进库的功能;各级气象台站可以很方便地通过宽带Internet网WinSock协议进入数据处理中心,按照自己的要求调用全省紫外线强度历史和实时资料,为本地紫外线预报提供有力的科学依据和手段。     

Twenty-five years of spectral UV-B measurements over Canada,Europe and Japan: Trends and effects from changes in ozone,aerosols, clouds,and surface reflectivity

Spectral UV records of solar irradiance at stations over Europe, Canada, and Japan were used to study long-term trends at 307.5 nm for a 25-year period, from 1992 to 2016. Ground-based measurements of total ozone, as well as satellite measurements of the Aerosol Index, the Total Cloud Cover and the surface reflectivity were also used in order to attribute the estimated changes of the UV to the corresponding changes of these factors. The present study shows that over the Northern Hemisphere, the long-term changes in UV-B radiation reaching the Earth's surface vary significantly over different locations, and that the main drivers of these variations are changes in aerosols and total ozone. At high latitudes, part of the observed changes may also be attributed to changes in the surface reflectivity. Over Japan, the UV-B irradiance at 307.5 nm has increased significantly by ∼3%/decade during the past 25 years, possibly due to the corresponding significant decrease of its absorption by aerosols. It was found that the greatest part of this increase took place before the mid-2000s. The only European station, over which UV radiation increases significantly, is that of Thessaloniki, Greece. Analysis of the clear-sky irradiance for the particular station shows increasing irradiance at 307.5 nm by ∼3.5%/decade during the entire period of study, with an increasing rate of change during the last decade, possibly again due to the decreasing absorption by aerosols.     

Influence of rotational darkening on ultraviolet interstellar extinction

Der Einfluß der Rotationsverdunklung schnell rotierender Sterne wird einer Neudiskussion unterzogen. Dafür werden filterphotometrische Helligkeiten vom Satelliten ANS herangezogen. Von schwach verfärbten B Sternen (E(B - V) 0.1 mag) wurden die Helligkeiten vom Einfluß der interstellaren Extinktion befreit. Die Verleilung der Sterne im Rotationsgeschwindigkeits-Farbenindex-Diagramm weist eine Streuung auf, die den Betrag der photometrischen Fehler übersteigt. Die Lage der Sterne im Rotationsgeschwindigkeits-Farbenindex-Diagramm befindet sich in qualitativer Übereinstimmung mit entsprechenden theoretischen Resultaten. Bei der Diskussion von individuell abweichenden Verläufen der interstellaren Extinktion vom durchschnittlichen Extinktionsgesetz sollte der Einfluß der Rotationsverdunklung als eine mögliche Quelle für die Abweichungen in Betracht gezogen und geprüft werden.     

Estimation of the <Emphasis Type="Italic">in situ</Emphasis> Ultraviolet-A absorption of seawater by a simple irradiance inversion model

An irradiance inversion model to estimate the in situ absorption coefficient of seawater has been developed for the Ultraviolet-A (UVA) wavelength domain. Input parameters are sun angle and the up-and downward planar irradiances measured for at least two depths. The present method does not require seawater to be sampled, and is a discrete wavelength method which returns the absorption coefficient at a given wavelength from the irradiances measured at that wavelength without assuming a spectral shape of any optical properties a priori. Comparison between the model results and spectrophotometric measurements shows that the model is practically useful when cloud cover in the atmosphere is ≤ 50%. According to the present method, measurements of the irradiances enable simultaneous observation of the in situ underwater UVA radiation level and the absorption capacity of bulk seawater using a radiometer.     

广西岛坪磷氯铅矿的谱学特征

磷氯铅矿(Pyromorphite)在我国比较罕见,2001年在广西岛坪发现的磷氯铅矿结晶较好,运用XRD、XRFI、R和UV/Vis等分析方法对黄色和绿色样品进行了研究。结果表明,二者XRD谱只是峰强有所不同。在它们的红外吸收谱带中,除了标准的PO43-吸收峰外,在670~800 cm-1之间和430 cm-1左右出现的两组肩峰为SiO44-振动峰。黄色样品的振动频率偏高、半峰宽偏窄、透射率与绿色样品相比较高。通过XRF分析发现黄色晶体比绿色晶体含有更多的Fe3 ,而Fe3 常使矿物呈现黄色,同时证实了黄色磷氯铅矿的红外吸收峰频率偏高是因为它的铅含量低于绿色矿。UV/Vis进一步说明在可见光区的吸收不同是使二者颜色差异的主要原因,Fe离子含量较大使磷氯铅矿呈现黄色。     

Sunlight Degradation of Aquatic Humic Substances Abbau von Huminstoffen unter dem Einfluß von Sonnenlicht

Coloured bog water and an aqueous solution of fulvic acid were exposed to natural sunlight. Up to 67% reduction in colour and 32% reduction in DOC concentration were measured after 12 days exposure. Colour bleaching and reduction in ultraviolet light absorbance were independent of added preservatives. The high molecular weight fraction of dissolved organic matter was most reduced in concentration while substances with low molecular weight increased. The reduction in absorbance (λ = 254 nm) per DOC was most significant for substances with high molecular weight. The final concentration of DOC was highest in samples where microbial activity was suppressed.     

三元络合物在光度法测钍中的应用

本文综述了近十几年中三元络合物在光度法测钍中的进展及显色剂的应用。     

太阳紫外光谱及NO2光解系数的观测

本文讨论了利用自动太阳光谱仪测量地面的紫外辐射光谱,并进一步计算了NO_2的光分解系数.光谱测量范围为310—375nm.测量结果表明,在北京地区秋季NO_2的光解系数变化在(1—4)×10~(-3)S~(-1),有明显的日变化.     

Ultraviolet absorption spectra of some Br-containing haloalkanes

The ultraviolet absorption cross sections were measured for CF₃Br, CF₂ClBr, CF₂Br-CF₂Br, CF₂Br₂, CHF₂Br, CHFBr-CF₃, CH₂Br-CF₃, CHClBr-CF₃ in the wavelength range 190–320 nm at 295 K. The photolysis is concluded to be the minor atmospheric sink for CHF₂Br, CHFBr-CF₃, CH₂Br-CF₃, CHClBr-CF₃.     

紫外线辐射增加对大豆的影响及其估算

在田间及盆栽试验中观测到经超量紫外线（UV280～400 nm）辐射处理的大豆作物，其株型、生理活动及产量均受到不同程度的影响，其影响量随UV辐射强度，大豆品种以及环境条件不同而异。文章还给出了计算紫外线辐射对大豆影响程度的公式，该计算方法效果较好。