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Polyaniline Formed in Alkaline Solution─A New Luminous Material 被引量:4
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作者 Nian Bing LI (College of Chemistry and Chemical Engineering, Southwest China Normal University, Chongqing 400715) Sheng Tao ZHANG, Pei Dao DING (College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第8期681-684,共4页
Electropolymerization of aniline in KOH solution and properties of the polymer are studied by using in situ reflex ellipsometry, cyclic voltammetry and fluorescence spectroscopic method. The change patterns of ellipso... Electropolymerization of aniline in KOH solution and properties of the polymer are studied by using in situ reflex ellipsometry, cyclic voltammetry and fluorescence spectroscopic method. The change patterns of ellipsometric parameters and the thickness of film in the process of electropolymerization are investigated. The complex refractive indices and the fluorescence spectra of PAN indicate that the PAN is a new kind of luminous material. 展开更多
关键词 POLYANILINE ELECTROPOLYMERIZATION alkaline solution luminous material.
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Study of An Unsymmetrical Shadow Mask PDP with High Luminous Efficacy 被引量:2
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作者 樊兆雯 张雄 +6 位作者 王保平 杨兰兰 屠彦 姜有燕 何万万 李青 汤勇明 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第2期207-210,共4页
A new shadow mask plasma display panel (SMPDP) is presented in this article. The unsymmetrical geometry structure of the discharge cell is its main feature. A macro-cell with a ratio of 40:1 was designed and fabric... A new shadow mask plasma display panel (SMPDP) is presented in this article. The unsymmetrical geometry structure of the discharge cell is its main feature. A macro-cell with a ratio of 40:1 was designed and fabricated. The geometrical parameters and electrode's structure of the discharge cell of the unsymmetrical SMPDP were optimized. Compared with current SMPDP, its luminous efficiency was obviously improved. Then a 32-inch wide video graphics array (WVGA) unsymmetrical SMPDP with a luminous efficacy of 1.8 Lm/W was produced. 展开更多
关键词 SMPDP unsymmetrical SMPDP luminous efficacy MACRO-CELL
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Influence of artificial luminous environment and TCM intervention on development of myopia rabbits 被引量:1
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作者 Yan Liu Yu-Liang Wang +2 位作者 Ke-Lei Wang Fang Liu Xia Zong 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第3期243-248,共6页
Objective:To explore the influence of artificial luminous environment and preventive function of traditional Chinese medicine(TCM) intervention based on "Theory of yin-yang clock" on myopia.Methods:A total o... Objective:To explore the influence of artificial luminous environment and preventive function of traditional Chinese medicine(TCM) intervention based on "Theory of yin-yang clock" on myopia.Methods:A total of 45 New Zealand young rabbits were randomly divided into 5groups,9 for each group.Control group was exposed in natural light.Fluorescent group and full spectrum group were exposed in fluorescent light and full spectrum light,on which basis fluorescent TCM group and full spectrum TCM group were added with "Rizhong Yinyang Formulas",respectively.Optical parameters were measured and the influence of different lights on the serum and retinal dopamine(DA) levels as well as the retinal histopathological tissues was observed.Results:The spectrum of fluorescent light mainly focused at 420-490 nm with the peak value of wavelength near 450 nm,whereas that of full spectrum was wider(400-800 nm) with the peak value near 600 nm.After 4 and 12 weeks,fluorescent group was evidently lower in serum and retinal DA levels(P<0.01).and there was no significant difference among full spectrum group,fluorescent TCM group and full spectrum TCM group(P>0.05).Histopathological observation showed that there was significant difference in pigment epithelium layer,photoreceptor and nerve fiber layer between fluorescent group and control group,but the difference among the test groups was not significant.Conclusions:Fluorescent light has certain influence on retinal histological construction and visual performance.However,TCM intervention may have some degree of protective function on retina. 展开更多
关键词 Full spectrum Artificial luminous environment RETINA DOPAMINE Visual performance Rizhong Yinyang FORMULAS
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Luminous Shapes with Unusual Motions as Potential Predictors of Earthquakes: A Historical Summary of the Validity and Application of the Tectonic Strain Theory 被引量:2
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作者 Michael A. Persinger John S. Derr 《International Journal of Geosciences》 2013年第2期387-396,共10页
For centuries and on every continent discrete shapes of lights with unusual motions have preceded earthquakes. The numbers of these lights per interval within a region have been strongly correlated with the amount of ... For centuries and on every continent discrete shapes of lights with unusual motions have preceded earthquakes. The numbers of these lights per interval within a region have been strongly correlated with the amount of seismic energy subsequently released within that region. These temporal intervals range between 3 months and 6 months for areas more than 500 kmin radius and less than a month for smaller radii. Other analyses have shown that the same tectonic strain associated with earthquakes is also associated with the display of luminous events before those earthquakes. This strain can be precipitated by injections of fluids into the crust, natural changes in hydrological loads on rivers, or, purposeful displacement of water into reservoirs. The strengths of the associations are sufficient to allow modest forecasting of earthquakes within the boundaries of the region and the temporal interval of analysis. More accurate utilization of these phenomena as prognosticators of specific earthquakes will require a re-evaluation of the manner by which these data are systematically recorded and interpreted. 展开更多
关键词 TECTONIC STRAIN luminous Phenomena Earthquake Forecasting HYDROLOGICAL Loads
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Investigation of thermal behavior of energetic and non-energetic binders on luminous efficiency of high performance miniature flares
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作者 Saeid Bagherpour Mohammad Mahdavi Ebrahim Abedini 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第2期193-197,共5页
Miniature flares containing magnesium/sodium nitrate compounded with different binders were studied for increasing luminosity and luminous efficiency in various fuel oxidizer ratio and flare diameters.Unsaturated poly... Miniature flares containing magnesium/sodium nitrate compounded with different binders were studied for increasing luminosity and luminous efficiency in various fuel oxidizer ratio and flare diameters.Unsaturated polyester, Bisphenol-A epoxy resin, calcium resinate, and nitrocellulose were used as binders for construction the flares. Experimental results showed that luminous efficiency was higher for polyester based flares. Due to the difference in decomposition progress of various binders and the exothermic reaction between binder and oxidizer the luminous efficiency of the mixtures were 31000,28900, 27800 and 25100 cd respectively for polyester, epoxy, calcium resinate, and nitrocellulose. It was found that nitrocellulose as an energetic binder produces the highest light intensity in comparison to other binders, but the burning rate is higher and the burning time is lower than the other binders.Thermal analysis of four binders showed that the heat of reactions was directly related to the amount of light output and luminosity. 展开更多
关键词 MINIATURE FLARE ILLUMINATING compositions luminous efficiency Binder
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ANALYSES OF THE DIFFERENCE BETWEEN IRRIGATED AND NONIRRIGATED AREA FOR LUMINOUS ENERGY UTILIZATION RATIO AND PRODUCTIVE POTENTIALITIES IN NINGXIA
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作者 Sun Fulu Ningxia Center of Climatological Date 《干旱区资源与环境》 CSCD 1993年第Z1期391-396,共6页
Situated in arid and semi-arid lands, the Ningxia Hui Autonomous Region is locatedat the middle reaches of the Yellow River. An adequate system of gravity irrigation was es-tablished in the north of Ningxia. Adding to... Situated in arid and semi-arid lands, the Ningxia Hui Autonomous Region is locatedat the middle reaches of the Yellow River. An adequate system of gravity irrigation was es-tablished in the north of Ningxia. Adding to abundant sunshine, strong solar radiation andmoderate heat, the agriculture is very developed. The south mountainous area of Ningxia, including both Yanchi and Tongxin counties,is short of rain, The vast lands cannot be irrigated. Nonirrigated agriculture and 展开更多
关键词 IRRIGATED AGRICULTURE RAINFED AGRICULTURE luminous Energy Utilization Ratio Productive POTENTIALS
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Diffusion Simulation of Outer Radiation Belt Electron Dynamics Induced by Superluminous L-O Mode Waves
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作者 肖伏良 何兆国 +2 位作者 张赛 苏振鹏 陈良旭 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第3期236-239,共4页
Temporal evolution of outer radiation belt electron dynamics resulting from superluminous L-O mode waves is simulated at L=6.5.Diffusion rates are evaluated and then used as inputs to solve a 2D momentum-pitch-angle d... Temporal evolution of outer radiation belt electron dynamics resulting from superluminous L-O mode waves is simulated at L=6.5.Diffusion rates are evaluated and then used as inputs to solve a 2D momentum-pitch-angle diffusion equation,particularly with and without cross diffusion terms.Simulated results demonstrate that phase space density(PSD)of energetic electrons due to L-O mode waves can enhance significantly within 24 h,covering a broader pitch-angle range in the absence of cross terms than that in the presence of cross terms.PSD evolution is also determined by the peak wave frequency,particularly at high kinetic energies.This result indicates that superluminous waves can be a potential candidate responsible for outer radiation belt electron dynamics. 展开更多
关键词 DYNAMICS luminous DIFFUSION
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Theoretical and experimental analysis of the effects of the series resistance on luminous efficacy in GaN-based light emitting diodes
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作者 马莉 沈光地 +3 位作者 刘建朋 高志远 徐晨 王勋 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期630-633,共4页
In this paper, a new equivalent circuit model of GaN-based light emitting diodes (LEDs) is established. The impact of the series resistance to luminous efficacy is simulated using the MATLAB software. GaN-based LEDs... In this paper, a new equivalent circuit model of GaN-based light emitting diodes (LEDs) is established. The impact of the series resistance to luminous efficacy is simulated using the MATLAB software. GaN-based LEDs with different n- contact electrode materials (LEDs with Ni/Au and LEDs with Cr/Au) are fabricated. By comparing and analyzing the results of performances, we concluded that both the series resistance and the carrier loss could affect the luminous efficacy severely. LEDs with lower series resistance have higher luminous efficacy and its efficiency droop is alleviated simultaneously. To improve luminous efficacy, the fabrication process should be optimized for lower series resistance. 展开更多
关键词 GaN-based light emitting diodes series resistance luminous efficacy
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Field Study on Indoor Thermal and Luminous Environment in Winter of Vernacular Houses in Northern Hebei Province of China
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作者 Shi-Meng Hao Ye-Hao Song +1 位作者 Jun-Jie Li Ning Zhu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第4期77-83,共7页
In this paper,a climate-adaptation study of vernacular houses in northern Hebei Province has been conducted based on quantitative field surveys. Three typical vernacular houses with different kinds of building envelop... In this paper,a climate-adaptation study of vernacular houses in northern Hebei Province has been conducted based on quantitative field surveys. Three typical vernacular houses with different kinds of building envelopes were selected. The field surveys included investigation on building material and construction,measurement of indoor thermal environment, infrared thermographic study of building envelopes and measurement of luminous environment. The results showed that the indoor air temperatures were below thermal comfort zone from late night till early morning and the horizontal temperature gradient was obvious. The adobe wall showed better thermal performance than the other two. As for the building layout,it is beneficial to put a storeroom on the north side of the house as a temperature buffer zone. Furthermore,due to missing insulation and the informal process of construction,significant amounts of heat escaped from building envelopes,especially from the corner of wall,ceiling and around the openings. The daylight factors on the work plan in the main rooms were accordance with design standards and the level of illuminance met the requirements of family's daily activities. 展开更多
关键词 thermal environment luminous environment vernacular houses sever cold zone
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Development of Flexible Luminous Fabrics for Photodynamic Therapy in Biomedical Applications
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作者 孔令豹 白紫千 《Journal of Donghua University(English Edition)》 EI CAS 2017年第6期719-721,共3页
Fabrics integrating with side-emitting polymer optical fiber( SE-POF) have great potentials for photodynamic therapy( PDT),which is a form of phototherapy recognized as a treatment strategy that is both minimally inva... Fabrics integrating with side-emitting polymer optical fiber( SE-POF) have great potentials for photodynamic therapy( PDT),which is a form of phototherapy recognized as a treatment strategy that is both minimally invasive and minimally toxic.Preliminary research has been undertaken to develop flexible luminous fabrics( FLF) device for PDT used in biomedical applications. The FLF device consists of SE-POFs, textile substrates,light source( LEDs or laser) with proper wavelength,and optical fiber coupling,etc. Different patterns of the fabrics were designed and fabricated purposely,and the light illumination effect was tested including the light power emitting from the patterned optical fiber fabrics,the stability of the illumination,and the light with different wavelengths. The work contributes to the successful development of an efficient and pain-alleviated illumination device for PDT in biomedical application. 展开更多
关键词 flexible luminous fabrics(FLF) photodynamic therapy(PDT) side-emitting fiber polymer optical fiber biomedical application
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Study of Luminous Emission from a Coaxial Plasma Discharge Device in the Presence of External Transverse Magnetic Field
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作者 Tarek M. Allam Hanaa A. El-Sayed Hanaa M. Soliman 《Energy and Power Engineering》 2011年第4期444-449,共6页
The experimental investigations in this paper are focused on the study of luminous radiation emission from coaxial plasma discharge device and the effect of applied transverse magnetic field Btr on it. The experiment ... The experimental investigations in this paper are focused on the study of luminous radiation emission from coaxial plasma discharge device and the effect of applied transverse magnetic field Btr on it. The experiment was done in (1.5 KJ - 10 KV) coaxial plasma discharge device. The discharge is operated in Nitrogen gas at pressures from 1 to 2.2 torr. Helmholtz magnetic coils are placed outside the coaxial electrodes with its axis at a distance = 3 cm from the coaxial electrodes muzzle, then Btr with a maximum induction ≈ 0.85 T is applied perpendicularly to the expanded plasma from the coaxial electrodes muzzle. The diagnostics used in the measurements include a Rogowsky coil and a photomultiplier tube equipped with light collimator. The experimental results showed that the maximum intensity of luminous radiation is detected at axial distance (side view) z = 8 cm and gas pressure, P = 2.2 torr. It also showed that the maximum value of axial luminous plasma zone velocity = 2.383 × 106 cm/s at z = 11 cm and P = 1.4 torr. In mode of presence of external Btr, the investigations have shown that, at P = 1.4 torr the maximum intensity of luminous radiation (detected at end-view position) is reduced by 17%, the full width at half maximum, FWHM of luminous radiation signal is increased by 40 times, while the luminous radiation signal is delayed by ta = 438 μs. In two modes of operation ta and FWHM have approximately a minimum values at P = 1.4 torr. 展开更多
关键词 COAXIAL DISCHARGE luminous Radiation TRANSVERSE Magnetic Field Energy LOSSES
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Theoretical Modeling of Luminous Efficacy for High-Power White Light-Emitting Diodes
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作者 陶雪慧 杨勇 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第3期121-125,共5页
The photometric characteristics of high-power white light-emitting diode (LED) devices are investigated. A theoretical model for the luminous efficacy o[ high-power white LED devices and LED systems is proposed. Wit... The photometric characteristics of high-power white light-emitting diode (LED) devices are investigated. A theoretical model for the luminous efficacy o[ high-power white LED devices and LED systems is proposed. With the proposed theoretical model, the mechanism of the luminous efficacy decrease is explained. Meanwhile, the model can be used to estimate the luminous efficacy oF LEDs under general operation conditions, such as different operation temperatures and injection currents. The wide validity of the luminous efficacy model is experimentally verified through the measurements of different types of LEDs. The experimental results demonstrate a high estimation accuracy. The proposed models not only can be applied to estimate the LED photometric performance, but also is helpful for reliability research of LEDs. 展开更多
关键词 exp Theoretical Modeling of luminous Efficacy for High-Power White Light-Emitting Diodes
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The researchers developed luminous rabbit
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《科技传播》 2013年第16期15-15,共1页
Their efforts produced two rabbits out of a litter of eight that went from being a normal, fluffy(蓬松的) white to glowing green in the dark. The rabbits were born at the University of Istanbul as part of a collaborat... Their efforts produced two rabbits out of a litter of eight that went from being a normal, fluffy(蓬松的) white to glowing green in the dark. The rabbits were born at the University of Istanbul as part of a collaboration between scientists from universities in Turkey and Hawaii. The rabbits glow to show that a genetic manipulation technique can work efficiently, 展开更多
关键词 luminous RABBIT COLLABORATION LITTER UNIVERSITIES
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Exploration on Research Methods for Exploring Human Response to Luminous Environment with Chromogenic Windows Applied
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作者 Runqi Liang Yupeng Wu +1 位作者 Jiawei Yao Yongming Zhang 《Journal of Electronic Research and Application》 2021年第3期34-39,共6页
Chromogenic windows enable both energy-saving and daylighting regulation.However,the human response to the luminous environment affected by them is difficult to test,since their features of dynamic change and tinting ... Chromogenic windows enable both energy-saving and daylighting regulation.However,the human response to the luminous environment affected by them is difficult to test,since their features of dynamic change and tinting automatically.This study explores the research methods,including experimental design and statistical analysis,by literature review and an experiment demonstration.The results show that a proper size of the test room is significant to obtain desired data,and the advanced VR technologies have the potential to be applied for testing these dynamic variables.Bayesian approaches are recommended to be tried and get more accurate interference about the experimental results. 展开更多
关键词 Chromogenic windows Building luminous environment Human response Statistical analysis Experimental design
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Black Sun: Ocular Invisibility of Relativistic Luminous Astrophysical Bodies
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作者 Jeffrey S. Lee Gerald B. Cleaver 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第4期562-570,共10页
Considered as a gedanken experiment are the conditions under which the relativistic Doppler shifting of visible electromagnetic radiation to beyond the human ocular range could reduce the incident radiance of the sour... Considered as a gedanken experiment are the conditions under which the relativistic Doppler shifting of visible electromagnetic radiation to beyond the human ocular range could reduce the incident radiance of the source, and render a luminous astrophysical body (LAB) invisible to a naked eye. This paper determines the proper distance as a function of relativistic velocity at which a luminous object attains ocular invisibility. 展开更多
关键词 Relativistic Processes Black Hole Physics Reference Systems luminous Astrophysical Body Relativistic Blackbody Spectrum
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Hydrogen sulfide:a luminous future in the postharvest preservation of fruits and vegetables
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作者 Ya-Qin Zhao Liang-Yi Zhao +3 位作者 Shun-Qing Hu Yuan-Yuan Hou Yong-Hua Zheng Peng Jin 《Food Materials Research》 2022年第1期27-37,共11页
Hydrogen sulfide(H_(2)S)has emerged as a signaling molecule that plays a crucial role in the postharvest preservation of fruits and vegetables.This review summarizes the various functions of H_(2)S such as delaying ri... Hydrogen sulfide(H_(2)S)has emerged as a signaling molecule that plays a crucial role in the postharvest preservation of fruits and vegetables.This review summarizes the various functions of H_(2)S such as delaying ripening and senescence,enhancing the resistance to cold and disease,and emphasizes the underlying mechanisms.Appropriate concentrations of H_(2)S primarily operate through stimulating the antioxidant system,while showing positive effects on physiological metabolism relevant to storage quality and shelf life including energy,sugar,proline,phenolic,membrane lipid and cell wall metabolism.Moreover,H_(2)S may reduce storage loss by modulating the expression patterns of senescence-related genes,like those linked to ethylene.The coordination of H_(2)S and nitric oxide(NO)combats ethylene-derived negative effects during ripening and senescence.High concentrations of H_(2)S not only act as a regulator to induce disease resistance,but also as a fungicide to inhibit the growth and pathogenicity of fungi.The intricate crosstalk between H_(2)S and other molecules exists via synergistic and antagonistic roles based on protein persulfidation,which is the major signaling process of H_(2)S and appears to compete with other post-translational modifications(PTMs)for the same cysteine residues.This review summarizes H_(2)S synthesis pathways and also discusses the correlation between the signals of H_(2)S,Ca^(2+)and ABA,while highlighting the intrinsic mechanisms of H_(2)S performing its functions in postharvest preservation. 展开更多
关键词 SULFIDE luminous SYNERGISTIC
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Microwave diagnostics of pulsed atmospheric discharge with electrolytic electrode and long-lived luminous formation in its afterglow
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作者 Shixin Zhao Xingbao Lyu +8 位作者 Aleksandr Astafiev Chengxun Yuan Lin Miao Jingfeng Yao Ying Wang Anatoly Kudryavtsev Aleksandr Chirtsov Gennadii Shabanov Zhongxiang Zhou 《High Voltage》 SCIE EI CSCD 2024年第1期127-136,共10页
The Gatchina discharge phenomenon holds significant promise as a laboratory model for simulating ball lightning.However,crucial aspects concerning the plasma components of the resulting afterglow remain unresolved.Not... The Gatchina discharge phenomenon holds significant promise as a laboratory model for simulating ball lightning.However,crucial aspects concerning the plasma components of the resulting afterglow remain unresolved.Notably,the measurement of the electron density,a critical parameter,has not been fully achieved thus far.In this study,microwave diagnostics and video recording were employed during a pulsed Gatchina discharge,along with synchronous measurement of discharge current and voltage.Distinct antennas were positioned at different heights to enable separate diagnosis of the discharge and the ensuing long-lived afterglow.The findings revealed that during the active phase of the Gatchina discharge,the plasma density was substantial enough to cause reflection of an electromagnetic wave with a frequency of 20 GHz from this highly conductive object.In the afterglow,the signal experienced only a moderate weakening of 10–20 percent,facilitating the determination of the time dependence of average electron density during the afterglow's passage between the two antennas.These measurements verified the unusually slow plasma decay in the afterglow of the Gatchina discharge,suggesting the potential significance of chemi-ionisation processes involving long-lived(metastable)particles. 展开更多
关键词 holds luminous electrolytic
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乳腺癌分子亚型多参数MRI特征的临床研究
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作者 郭峰 侯信明 +2 位作者 王春锋 张海芹 宋张骏 《中国CT和MRI杂志》 2024年第7期111-113,共3页
目的探讨乳腺肿瘤的多参数MRI特征(T_(2)-WI、ADC值和DCE)以及乳腺密度和背景实质增强(BPE)特征在不同乳腺癌(BC)分子亚型中的差异,以期为临床诊断提供重要参考。方法本研究为回顾性研究,纳入344例患者。所有患者均接受了多参数乳房MRI(... 目的探讨乳腺肿瘤的多参数MRI特征(T_(2)-WI、ADC值和DCE)以及乳腺密度和背景实质增强(BPE)特征在不同乳腺癌(BC)分子亚型中的差异,以期为临床诊断提供重要参考。方法本研究为回顾性研究,纳入344例患者。所有患者均接受了多参数乳房MRI(T_(2)WI、ADC和DCE序列),并根据最新的BIRADS提取特征,使用ROI之间的类内系数(ICC)来评估读者间协议。结果研究人群分为:luminal A 89例(26%),luminal B HER2阳性39例(11.5%),luminal B HER2阴性168例(48.5%),三阴性(TNBC)41例(12%),HER2富集7例(2%)。Luminal内A肿瘤与特殊的组织学类型、最小的肿瘤大小和持续的动力学曲线相关(P均<0.05)。Luminal B HER2阴性肿瘤与最低ADC值相关(0.77×10^(-3)mm^(2)/s^(2)),其预测BC分子亚型的准确性为0.583。TNBC与不对称和中度/显著BPE,圆形/椭圆形肿块,边缘受限和边缘增强相关(P均<0.05)。HER2富集的BC与最大肿瘤大小相关(平均37.28mm,p值=0.02)。结论BC分子亚型与T_(2)WI、ADC和DCE MRI特征相关,ADC有助于预测luminal B HER2阴性病例。 展开更多
关键词 乳腺癌 MRI特征 luminal分型
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Classical Cosmology II. The Einstein Ring
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作者 Lorenzo Zaninetti 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期574-598,共25页
The Einstein ring is usually explained in the framework of the gravitational lens. Conversely here we apply the framework of the expansion of a superbubble (SB) in order to explain the spherical appearance of the ring... The Einstein ring is usually explained in the framework of the gravitational lens. Conversely here we apply the framework of the expansion of a superbubble (SB) in order to explain the spherical appearance of the ring. Two classical equations of motion for SBs are derived in the presence of a linear and a trigonometric decrease for density. A relativistic equation of motion with an inverse square dependence for the density is derived. The angular distance, adopting the minimax approximation, is derived for three relativistic cosmologies: the standard, the flat and the wCDM. We derive the relation between redshift and Euclidean distance, which allows fixing the radius of the Einstein ring. The details of the ring are explained by a simple version of the theory of images. 展开更多
关键词 COSMOLOGY Observational Cosmology Gravitational Lenses luminous Arcs
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YAGG:Ce transparent ceramics with high luminous efficiency for solid-state lighting application 被引量:19
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作者 Hui HUA Shaowei FENG +7 位作者 Zhongyu OUYANG Hezhu SHAO Haiming QIN Hui DING Qiping DU Zhijun ZHANG Jun JIANG Haochuan JIANG 《Journal of Advanced Ceramics》 SCIE CSCD 2019年第3期389-398,共10页
A series of Y2.985Al5–xGaxO12:0.015Ce(YAGG:Ce,x=0,1,2,3,4,5)transparent ceramics were prepared via a solid-state reaction method.Two-step sintering technique was proved to be an effective approach to prepare function... A series of Y2.985Al5–xGaxO12:0.015Ce(YAGG:Ce,x=0,1,2,3,4,5)transparent ceramics were prepared via a solid-state reaction method.Two-step sintering technique was proved to be an effective approach to prepare functional ceramics with high Ga concentration,and Y3Ga5O12(YGG)transparent ceramic was successfully prepared for the first time.According to the variation of Al/Ga ratio,regulation of band structure and luminescence properties of YAGG:Ce transparent ceramics were effectively investigated.When Ga substitutes Al sites,the tetrahedral site is more favorable compared to the octahedral site for Ga to occupy according to the first-principle calculation.A continuous blue shift of the emission from 565 to 515 nm was achieved as Ga was gradually introduced into Y3Al5O12:Ce matrix.High quality green light was obtained by coupling the YAGG:Ce ceramics with commercial blue InGaN chips.Transparent luminescence ceramics accomplished in this work can be quite prospective for high power LED application. 展开更多
关键词 YAGG:Ce transparent ceramics TWO-STEP sintering Al/Ga ratio luminous efficiency green-emitting LEDS
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