激光医学中的光辐射量

各种光辐射量的标准符号和定义的使用,在学科联系和国际交流中是非常重要的。许多国家和国际学术机构已认识到激光医学领域需要一套统一的、实用的、适用于世界范围的术语。国家计量局对此也有明确要求。此文所述目前国际上通用的光辐射量的术语、定义和单位,对我国激光医学的科学研究和论文著作的规范化、标准化具有重要意义。

激光医学中光辐射量的测量──国外相关标准测量技术评介

我们已经专文介绍了激光医学中的光辐射量〔１〕。它们是激光临床治疗和基础研究工作中的主要物理量。因此，光辐射量的实验测量成为激光医学领域中临床治疗和研究工作的必备手段。国际电气技术委员会（ＩＥＣ）要求每一个医用激光产品都必须配置激光辐射量测量仪器〔２〕...

倍量光辐射柔光灯的研究与开发

本文论述了一款基于高斯成像理论与非成像光学软件技术结合的具有与普通柔光灯相比光能辐射加倍的节能型"倍量光辐射柔光灯"的研究与设计方法。

日光温室温光环境对黄瓜茎叶生长的影响

观察了冬季日光温室光照和温度条件对黄瓜茎叶生长的影响。结果表明:光辐射量、见光时段小时积温、日均积温及20 cm地温能有效反映黄瓜茎叶生长的动态变化。光辐射量是影响冬季日光温室黄瓜生长的主要因素,而见光时段小时积温对黄瓜茎叶生长有更为直观的影响。冬季连阴几天放晴后,黄瓜植株的生长有一定的滞后期,与10～20 cm的土壤温度回升慢有直接的关系。

日光温室温光条件对黄瓜叶片及瓜条生长的影响

以津强210黄瓜为试材,利用光温环境监测装置,研究了下挖式日光温室春季温光环境的变化对黄瓜结瓜前期叶片及瓜条生长的影响。结果表明:在下挖式日光温室中,春季黄瓜结瓜前期叶面积日均增长量与日均气温和光辐射量呈极显著正相关,瓜条日均增长量与见光时段小时积温也呈极显著正相关;见光时段平均气温、日均气温和日均光照强度也都显著影响着叶面积和瓜条日均增长量,但瓜条日均增长量与夜均气温相关性不显著。

Estimation of Net Primary Productivity of Terrestrial Vegetation in China by Remote Sensing

Among the many approaches for studying the net primary productivity (NPP), a new method by using remote sensing was introduced in this paper. With spectral information source (the visible band, near infrared band and thermal infrared band) of NOAA-AVHRR, we can get the relative index and parameters, which can be used for estimating NPP of terrestrial vegetation. By means of remote sensing, the estimation of biomass and NPP is mainly based on the models of light energy utilization. In other words, the biomass and NPP can be calculated from the relation among NPP, absorbed photosynthetical active radiation (APAR) and the rate (epsilon) of transformation of APAR to organic matter, thus: NPP = ( FPAR x PAR) x [epsilon * x sigma (T) x sigma (E) x sigma (S) x (1 - Y-m) x (1 - Y-g)]. Based upon remote sensing ( RS) and geographic information system (GIS), the NPP of terrestrial vegetation in China in every ten days was calculated, and the annual NPP was integrated. The result showed that the total NPP of terrestrial vegetation in China was 6.13 x 10(9) t C . a(-1) in 1990 and the maximum NPP was 1 812.9 g C/m(2). According to this result, the spatio-temporal distribution of NPP was analyzed. Comparing to the statistical models, the RS model, using area object other than point one, can better reflect the distribution of NPP, and match the geographic distribution of vegetation in China.

飞机风挡透过的光辐射与飞行员视力

简介光辐射对眼组织有急性和慢性影响，尤其是作用剂量超过正常修复能力时。在国家安全部项目支持下，联邦航空局民用航空航天医学研究所对飞机风挡的可见和不可见透过光辐射量进行了测量，本实验主要测量的是紫外线（UV，波长小于380nm）和可见光（波长380～780nm）。方法测量了8种飞机风挡，包括三种风挡来自喷气商用机的麦道88、空客A380和波音727／737，2种风挡来自商用螺旋桨客机Fokker27和ATR42机型，

Studies on Physiological Radiation Spectrum and Fruit Quality of Sweet Cherry in Different Canopies

[ Objective] The physiological radiation spectrum and fruit quality in different canopies of sweet cherry tree were studied. [ Method] Opti- cal fiber spectrum was applied to determine the physiological radiation spectrum in different canopies of sweet cherry tree. The fruit quality in differ- ent canopies was determined. [Result] The results showed that from the top part to the lower part and from the outer part to inner part of sweet cherry canopy, Me physiological radiation intensity and ratio of short wave light reduced significantly, while ratio of long wave light increased. Fruit mass, Vc, TSS and total sugar content were significantly decreasing, while organic acid content increasing, but the fruit edible percent was similar. Furthermore, the physiological radiation intensity was strong, fruit mass, TSS, Vc and total sugar content increased, but organic acid content re- duced. [ Condusion] The higher and bigger canopy of sweet cherry, the poor and lower physiological radiation intensity, photosynthesis accumula- tion and fruit quality. The study provided theoretical foundation and reference for the trim of sweet cherry.

Modeling Gross Primary Production by Integrating Satellite Data and Coordinated Flux Measurements in Arid and Semi-Arid China

Assessing large-scale patterns of gross primary production (GPP) in arid and semi-arid (ASA) areas is important for both scientific and practical purposes.Remote sensing-based models,which integrate satellite data with input from ground-based meteorological measurements and vegetation characteristics,improve spatially extended estimates of vegetation productivity with high accuracy.In this study,the authors simulated GPP in ASA areas by integrating moderate resolution imaging spectral radiometer (MODIS) data with eddy covariance and meteorological measurements at the flux tower sites using the Vegetation Photosynthesis Model (VPM),which is a remote sensing-based model for analyzing the spatial pattern of GPP in different land cover types.The field data were collected by coordinating observations at nine stations in 2008.The results indicate that in the region during the growing season GPP was highest in cropland sites,second highest in woodland sites,and lowest in grassland sites.VPM captured the temporal and spatial characteristics of GPP for different land covers in ASA areas.Further,Enhanced Vegetation Index (EVI) had a strong liner relationship with GPP in densely vegetated areas,while the Normalized Difference Vegetation Index (NDVI) had a strong liner relationship with GPP over less dense vegetation.This study demonstrates the potential of satellite-driven models for scaling-up GPP,which is a key component for studying the carbon cycle at regional and global scales.

Effect of Substitution Site on Two-Photon Absorption and Excited States Properties of Lipid Droplets Detection NAPBr Dyes:a Theoretical Perspective

Two-photon fluorescence dyes have shown promising applications in biomedical imaging.However,the substitution site effect on geometric structures and photophysical properties of fluorescence dyes is rarely illustrated in detail.In this work,a series of new lipid droplets detection dyes are designed and studied,molecular optical properties and non-radiative transitions are analyzed.The intramolecular weak interaction and electron-hole analysis reveal its inner mechanisms.All dyes are proven to possess excellent photophysical properties with high fluorescence quantum efficiency and large stokes shift as well as remarkable two-photon absorption cross section.Our work reasonably elucidates the experimental measurements and the effects of substitution site on two-photon absorption and excited states properties of lipid droplets detection NAPBr dyes are highlighted,which could provide a theoretical perspective for designing efficient organic dyes for lipid droplets detection in biology and medicine fields.

Physiological responses of macroalga Gracilaria lemaneiformis(Rhodophyta) to UV-B radiation exposure

This paper aims to evaluate the effects of ultraviolet-Bradiation(UVBR) on Gracilaria lemaneiformis,a commercial red macroalga and an important source of agar. To study the in-vitro effect of UVBR on G. lemaneiformis,this plant was cultivated and exposed to photosynthetically active radiation(PAR) at 40 μmol photons/(m2 ·s) and enhanced UVBR(0,0.36,0.72,1.08,1.44,and 1.80 k J/(m 2 ·d)) for 13 days. The samples were processed for histochemical analysis,and the growth rate,photosynthetic pigment contents,photosynthetic performance,reactive oxygen species levels,membrane permeability,malonyl dialdehyde contents and antioxidant capacity of G. lemaneiformis were investigated. After 13 days of exposure to PAR+UVBR,G. lemaneiformis showed photodamage and photoinhibition of photosynthetic pigments(chlorophylla and phycoerythrin),leading to a decreased photosynthetic efficiency. Further,there was a corresponding decrease in the relative growth rates and depigmentation and partial necrosis of the apical segments were noted after exposure to PAR+UVBR. Additionally,UVBR induced excess production of superoxide radicals and hydrogen peroxide,eliciting a marked cellular membrane damage and antioxidative response.

The Influence of Diode and He-Ne Lasers on Corn and Wheat Seeds

The paper presents a study on the effects of low intensity laser irradiation on morphological changes in plants sprouted from maize hybrid seeds （two hybrids） and wheat seeds. Pre-sowing laser irradiation treatment on the seeds was done, intervals from 10 s to 15 min （approximately）, by using a diode laser output power of 12 mW at 904 nm wavelength or with He-Ne laser with output power of 50 mW and 632.8 nm wavelength. Before irradiation seeds were divided into groups （wet and dry, and then in subgroups-irradiated or control groups）. We used maize hybrids, Amilacea and Identata and wheat （Triticum aestivum）. The reflection coefficient in visible range was done for maize varieties. Obtained data show the influence of laser beam to better plant growth. Better results are obtained for dry seed irradiation than for wet. In order to investigate the effect of laser beam and in general to clarify a lot of unsolved photo processes related to bioorganisms at macroscopic and microscopic levels, some optical constants of selected plant families were researched. At the same time, the influence of laser beams of common wavelengths to the selected plants was monitored. Morphological processes of plants （seeds and leaves） irradiated under different conditions and plant growing dynamics were contemplated. The definite correlation analyses of obtained results were made, clearly speaking about the influence of small-dose radiation to characteristics （quantitative and other genetic, bio-stimulating effects） of future plant growth.

Investigation on the binding of （-）-epigallocatechin-3-O-gallate to bovine serum albumin by molecular spectroscopy

The binding of （-）-epigallocatechin-3-O-gallate （EGCG） to bovine serum albumin （BSA） were investigated for the first time with spectral methods, including fluorescence and absorption spectrometry under simulative physiological conditions. A strong fluorescence quenching reaction of EGCG to BSA was observed. It was proved that the fluorescence quenching of BSA by addition of EGCG was a result of the formation of EGCG-BSA complex. The binding constant K and the number of binding sites n were determined at physiological conditions and three different temperatures with fluorescence quenching method. The binding distance R and transfer efficiency E between BSA and EGCG were also obtained according to Forster theory of non-radiation energy transfer. The effects of Al^3＋, Cu^2＋, Mg^2＋ and Fe^2＋ on the binding constant between EGCG and BSA were studied at 298 K. The effect of EGCG on the conformation of BSA was also analyzed by synchronous fluorescence spectroscopy. PACS. 21. 10. Dr; 32. 50. ＋d; 32. 30. Jc; 82.80. Dx

Molecular Frame Photoemission： Probe of the Photoionization Dynamics for Molecules in the Gas Phase

Molecular frame photoemission is a very sensitive probe of the photoionization （PI） dynamics of molecules. This paper reports a comparative study of non-resonant and resonant photoionization of D2 induced by VUV circularly polarized synchrotron radiation at SOLEIL at the level of the molecular frame photoelectron angular distributions （MFPADs）. We use the vector correlation method which combines imaging and time-of-flight resolved electron-ion coincidence techniques, and a generalized formalism for the expression of the Ⅰ（χ, θe, Фe） MFPADs, where χ is the orientation of the molecular axis with respect to the light quantization axis and （θe, Фe） the electron emission direction in the molecular frame. Selected MFPADs for a molecule aligned parallel or perpendicular to linearly polarized light, or perpendicular to the propagation axis of circularly polarized light, are presented for dissociative photoionization （DPI） of D2 at two photon excitation energies, hv=19 eV, where direct PI is the only channel opened, and hv=32.5 eV, i.e. in the region involving resonant excitation of Q1 and Q2 doubly excited state series. We discuss in particular the properties of the circular dichroism characterizing photoemission in the molecular frame for direct and resonant PI. In the latter case, a remarkable behavior is observed which may be attributed to the interference occurring between undistinguishable autoionization decay channels.

The definition analyses of radiation temperature measurement area

In the research of primary spectrum pyrometry, this paper discussed the definition problem of radiation temperature measurement area based on the measurement coordinates. For the linear spectrum emissivity model and improved monotonic spectrum emissivity model, the characteristics of radiation temperature measurement area restricted by the measurement coordinates were theoretically analyzed, through the investigations of the temperature and emissivity coordinate axes. Choosing the specific primary spectrum pyrometer as an example in applications, the theoretical area of radiation temperature measurement of this pyrometer was given and it was verified through blackbody experiments. The discussions of this paper will provide the necessary foundation for the theory research development of primary spectrum pyrometry and the realization of technical applications.

Renewable Energy Sources and Pricing of Electrical Power

This report deals with some characteristics of the electric power system of Bulgaria. Emphasis is put on the benefits of joining the small photovoltaic plants in the tourist areas of the country. As an example of that the town of Pomorie is examined. Data on the quality of the consumed electric energy and the price per a four-member family are presented. The amount of the solar radiation for the town of Pomorie is audited through the PVGIS （Photovoltaic Geographical Information System）. Discussed are the types of photovoltaic panels offered on the market by manufacturers in terms of the received power efficiency. Developed is a model of creating a photovoltaic system on the roof of a house, inhabited by several families. Calculations are made on the cost of the electricity generated by the proposed system. Compared is the cost of the electricity supplied by the electricity provider EVN （Energie Verntinftig Nutzen） in the town of Pomorie to the one that will be obtained using the proposed PV-system.

Theoretical analysis of radiation-balanced double clad fiber laser

In this letter,a theoretical model of radiation-balanced double clad fiber laser is presented.The characteristic of the laser with Yb doped double clad fiber is analyzed numerically.It is concluded that high output laser power can be obtained by selecting output coupling mirror with lower reflectivity,improving Yb doped concentration and choosing fiber length. This result can help us to design radiation balanced fiber laser.

Verification of the stomatal conductance of Nebbiolo grapevine

Wine is one of the most important Italian export products,and Nebbiolo is one of the most respected Italian grapes. In the summer of 2007,a measurement campaign was carried out in a Nebbiolo vineyard located in Vezza d’Alba,near Cuneo,Italy. Using a gauge of trade gases and some other instruments,we recorded the stomatal conductance and also some physiological parameters useful for estimating the dependence of stomatal conductance on environmental variables. The goal of this experiment was improving the parameterization of grapevine evapotranspiration through the assessment of the stomatal conductance and,in particular,of the functional dependence of the stomatal conductance on the following variables:the photosynthetically active radiation,the atmospheric temperature,the atmospheric moisture deficit,and the carbon dioxide concentration. The observations allowed us to check and,in some cases,to adapt the existing general parameterizations found in literature. The results showed some significant differences with the existing parameterizations concerning the atmospheric temperature,the atmospheric moisture deficit,and the carbon dioxide concentration. The parameterizations obtained in this experiment,although referring to a specific plant and site(namely the Nebbiolo at Vezza d’Alba),could allow assessment of the best environmental conditions under which the Nebbiolo grapevine production is the best,and in future could be tested for other grapevines or climates.

Bremsstrahlung Radiation of Fast Electrons in Long Air Gaps

The results of an experiment on discharges in long atmospheric pressure air gaps at a pulsed voltage of amplitude up to 800 kV and risetime 150-200 ns are analyzed. In the experiment, a radiation pulse of photon energy 〉 5 keV and duration 10-20 ns has been detected. It has been shown that the x-ray pulse is due to the ＂runaway＂ of electrons from the head of an anode-directed streamer. The estimated maximum bremsstrahlung energy is about 5-10 keV. The presence of a maximum in the bremsstrahlung spectrum is due to that the photons emitted by electrons are absorbed by atoms of the gas in which the discharge operates.

Facile Synthesis of Coronene Dimers Having Unique Optical Properties

The authors synthesized very pure dimer phase of coroneae by simple heat-treatment and subsequent sublimation purification. It was confirmed by laser desorption/ionization mass spectroscopy measurements that pure dimer phase of coronenes can be obtained by controlling the fusing and sublimation temperatures. The crystal structure of the dimer phase was analyzed by synchrotron XRD （X-ray diffraction） experiments. It was also found that very bright red light is emitted by irradiating ultra violet light （λ = 350 nm） to the dimer phase. The external and internal quantum yields were determined to be 5.56% and 6.95%, respectively.