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Evaluating the Effects of Graviton Redshift upon Spiral Galaxy Rotation Curves, Surface Brightness Magnitudes and Gravitational Lensing
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作者 Firmin J. Oliveira 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期967-985,共19页
The effects of the gravitational redshift of gravitons upon spiral galaxy rotation energy are compared to the standard mass to light analyses in obtaining rotation curves. The derivation of the total baryonic matter c... The effects of the gravitational redshift of gravitons upon spiral galaxy rotation energy are compared to the standard mass to light analyses in obtaining rotation curves. The derivation of the total baryonic matter compares well with the standard theory and the rotation velocity is matched to a high precision. The stellar mass distributions obtained from the fit with graviton energy loss are used to derive the surface brightness magnitudes for the galaxies, which agree well with the observed measurements. In a new field of investigation, the graviton theory is applied to the observations of gravitational lenses. The results of these applications of the theory suggest that it can augment the standard methods and may eliminate the need for dark matter. 展开更多
关键词 GRAVITONS Gravitational Redshift Surface brightness Gravitational Lens Lens Mass
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A rapid assessment of MWRI-RM/FY3G brightness temperature
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作者 Wenying He Xinran Xia +5 位作者 Shengli Wu Peng Zhang Hongbin Chen Xiang'ao Xia Yuquan Zhou Miao Cai 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第3期42-46,共5页
2023年4月发射的FY-3G上搭载17个频率的测雨微波成像仪(MWRI-RM),其业务定标的微波亮温(Tb)数据于2023年10月23日公开发布.本文比对了发布10天的MWRI-RM与全球降水测量(GPM)卫星上的微波成像仪(GMI)相匹配的Tb数据,并借助辐射传输模式... 2023年4月发射的FY-3G上搭载17个频率的测雨微波成像仪(MWRI-RM),其业务定标的微波亮温(Tb)数据于2023年10月23日公开发布.本文比对了发布10天的MWRI-RM与全球降水测量(GPM)卫星上的微波成像仪(GMI)相匹配的Tb数据,并借助辐射传输模式进行双差分(DD)交叉定标分析,旨在快速评估新一代MWRI-RM观测数据质量.观测比较表明,MWR1-RM与GMI测量的Tb一致性很好,大多通道的平均偏差(MBE)和均方根误差(RMSE)均小于1K.两种传感器由于观测角度略有不同在水面产生约0.5 K差异.DD分析也展示出MWRI-RM的大多数通道性能与GMI相当接近,尤其是首次启用的高频166 GHz和183 GHz. 展开更多
关键词 FY3G MWRI-RM GMI 亮度温度 双差分方法
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Gamma Correction for Brightness Preservation in Natural Images
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作者 Navleen S Rekhi Jagroop S Sidhu Amit Arora 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2791-2807,共17页
Due to improper acquisition settings and other noise artifacts,the image degraded to yield poor mean preservation in brightness.The simplest way to improve the preservation is the implementation of histogram equalizat... Due to improper acquisition settings and other noise artifacts,the image degraded to yield poor mean preservation in brightness.The simplest way to improve the preservation is the implementation of histogram equalization.Because of over-enhancement,it failed to preserve the mean brightness and produce the poor quality of the image.This paper proposes a multi-scale decomposi-tion for brightness preservation using gamma correction.After transformation to hue,saturation and intensity(HSI)channel,the 2D-discrete wavelet transform decomposed the intensity component into low and high-pass coefficients.At the next phase,gamma correction is used by auto-tuning the scale value.The scale is the modified constant value used in the logarithmic function.Further,the scale value is optimized to obtain better visual quality in the image.The optimized value is the weighted distribution of standard deviation-mean of low pass coefficients.Finally,the experimental result is estimated in terms of quality assessment measures used as absolute mean brightness error,the measure of information detail,signal to noise ratio and patch-based contrast quality in the image.By comparison,the proposed method proved to be suitably remarkable in retaining the mean brightness and better visual quality of the image. 展开更多
关键词 Natural and aerial images wavelet transform gamma correction brightness preservation
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Chinese Space Telescopes Accurately Measure the Brightest Gamma-ray Burst Ever Detected
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《Bulletin of the Chinese Academy of Sciences》 2023年第1期40-41,共2页
At 2 a.m.on March 29,2023(Beijing Time),the Institute of High Energy Physics(IHEP)of the Chinese Academy of Sciences(CAS),together with some 40 research institutions worldwide,released their latest discoveries on the ... At 2 a.m.on March 29,2023(Beijing Time),the Institute of High Energy Physics(IHEP)of the Chinese Academy of Sciences(CAS),together with some 40 research institutions worldwide,released their latest discoveries on the brightest Gamma-Ray Burst(dubbed as GRB 221009A)ever detected by humanity.With the unique observations made by two Chinese space telescopes,namely Insight-HXMT and GECAM-C,scientists were able to accurately measure how bright and how much energy was released by this burst,which is the key to understanding this historical event. 展开更多
关键词 Det bright bright
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Bright Lights,Big Laughs
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作者 CUI XIAOQIN 《ChinAfrica》 2023年第4期54-55,共2页
Stand-up comedy shows good potential in China as audience turnout at live shows rises On the third floor of Bitaomai Life Plaza, a shopping mall in Beijing, is a comedy club named Kangaroo Comedy. It is a place where ... Stand-up comedy shows good potential in China as audience turnout at live shows rises On the third floor of Bitaomai Life Plaza, a shopping mall in Beijing, is a comedy club named Kangaroo Comedy. It is a place where people can watch a live stand-up comedy show, still a novelty to many Chinese, and indulge in hours of laughter.“Influenced by the popularity of online variety shows,stand-up comedy has gone viral in China over the past few years. 展开更多
关键词 SHOPPING FLOOR bright
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Bright Yellow 2烤烟热激蛋白90生物信息学分析 被引量:17
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作者 陈二龙 苏家恩 +4 位作者 范志勇 朱凯 王德勋 孙军伟 宋朝鹏 《南方农业学报》 CAS CSCD 北大核心 2017年第10期1734-1740,共7页
【目的】分析Bright Yellow 2烤烟热激蛋白90(HSP90)的生物学信息,为揭示烘烤过程中烟叶的烘烤特性提供理论依据。【方法】从NCBI中获取Bright Yellow 2烤烟HSP90蛋白序列Nt HSP-1、Nt HSP-2和Nt HSP-3(Gen Bank登录号分别为BAL42333、B... 【目的】分析Bright Yellow 2烤烟热激蛋白90(HSP90)的生物学信息,为揭示烘烤过程中烟叶的烘烤特性提供理论依据。【方法】从NCBI中获取Bright Yellow 2烤烟HSP90蛋白序列Nt HSP-1、Nt HSP-2和Nt HSP-3(Gen Bank登录号分别为BAL42333、BAL42332和BAM24708),利用生物信息学软件对各序列进行理化特性、跨膜区、信号肽、亚细胞定位、二级结构和三级结构预测分析。【结果】Bright Yellow 2烤烟Nt HSP-1、Nt HSP-2和Nt HSP-3的氨基酸数量分别为812、811和699个,均以酸性氨基酸含量较多,其中谷氨酸(Glu)含量最高,理论等电点均小于5.00,二级结构均以α-螺旋(H)和无规则卷曲(C)为主。Nt HSP-1和Nt HSP-2的亲水性较高,具有较高的稳定性,属于分泌蛋白,具有锚定结构,定位于内质网,其三级结构呈现"r"形,N端内部具有Mg2+结合位点、HATPase_c(ATP酶)和top6b(DNA拓扑异构酶VI)功能域;Nt HSP-3为非分泌型蛋白,定位于叶绿体,三级结构呈现"i"形,N端含有Mg2+结合位点和HATPase_c功能域。【结论】Nt HSP-1和Nt HSP-2可能与烟叶耐烤性有关,而Nt HSP-3可能与烟叶易烤性有关。 展开更多
关键词 烤烟 brightYellow2 热激蛋白90(HSP90) 生物信息学 烘烤
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脐血中CD56^(bright)CD16^(dim)/^-NK细胞亚群的检测 被引量:3
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作者 孙健 陈军浩 张葵 《中国实验诊断学》 2012年第11期2060-2062,共3页
目的了解新生儿脐血NK细胞和CD56bright CD16dim/-NK细胞亚群的比率,探讨CD56bright CD16dim/-NK细胞在脐血低免疫应答中的作用。方法使用血细胞分析仪计数淋巴细胞;采用流式细胞术检测脐血、母亲及对照组中NK细胞和CD56bright CD16dim/... 目的了解新生儿脐血NK细胞和CD56bright CD16dim/-NK细胞亚群的比率,探讨CD56bright CD16dim/-NK细胞在脐血低免疫应答中的作用。方法使用血细胞分析仪计数淋巴细胞;采用流式细胞术检测脐血、母亲及对照组中NK细胞和CD56bright CD16dim/-NK细胞亚群的比率。结果脐血中淋巴细胞计数显著高于母亲及对照组;NK细胞比率无显著性差异;CD56bright CD16dim/-NK细胞高于母亲及对照组;母亲组CD56bright CD16dim/-NK细胞高于对照组。结论脐血中丰富的CD56bright CD16dim/-NK细胞是脐血低免疫应答的原因之一。 展开更多
关键词 脐血 NK细胞 CD56bright CD16dim -NK细胞
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Synthesis of a Fluorophore with Improved Optical Brightness
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作者 Macduff Okuom Mark Wilson +9 位作者 Jordan Groathouse Junsik Lee Dave Symonsbergen Casey Gustafson Mitch Trauernicht Homar Barcena Cassie Reicks Sharmin Sikich Raychelle Burks Andrea Holmes 《International Journal of Organic Chemistry》 2013年第4期256-261,共6页
The synthesis and characterization of a novel fluorophore(1), with potential application as an optical brightener are reported. This compound was prepared by reacting 4,4-diaminostilbene-2,2-disulfonic acid with cyanu... The synthesis and characterization of a novel fluorophore(1), with potential application as an optical brightener are reported. This compound was prepared by reacting 4,4-diaminostilbene-2,2-disulfonic acid with cyanuric chloride in the presence of Na2CO3 followed by the addition of trityl aniline. Solution and solid state fluorescence demonstrated a strong blue/purple emission centered at 450 nm. 1H-NMR spectroscopy, mass spectrometry analysis, elemental analysis, and DOSY-NMR were used for the characterization of the fluorophore. 展开更多
关键词 OPTICAL brightENER FLUOROPHORE Diaminostilbene Cyanuric CHLORIDE OPTICAL brightNESS
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肝细胞癌患者外周血CD3bright T细胞CD27与PD1表达的应用研究 被引量:1
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作者 金方方 刘宁 +3 位作者 严艳 金子铮 文凤 娄金丽 《北京医学》 CAS 2019年第6期460-463,共4页
通过对肝细胞癌(hepatocellular carcinoma, HCC )>者外周血CD3高表达T细胞(CD3brightT细胞)表型特点与治疗前后细胞CD27.PD1表达变化的分析,探讨CD3brightT细胞在肝癌进展中的临床意义。方法选取2018年9月至2019年2月首都医科大学... 通过对肝细胞癌(hepatocellular carcinoma, HCC )>者外周血CD3高表达T细胞(CD3brightT细胞)表型特点与治疗前后细胞CD27.PD1表达变化的分析,探讨CD3brightT细胞在肝癌进展中的临床意义。方法选取2018年9月至2019年2月首都医科大学附属北京佑安医院CD3bnght T细胞阳性的原发性HCC患者23例为HCC组,收集患者术前与术后1个月时临床当天检测剩余的全血标本,同时收集健康人30例为对照组,在流式细胞平台上进行CD3brightT细胞的T细胞受体类型、CD27分子与PD1表达水平的检测,同时收集患者临床资料用于统计学分析。结果CD3bright T细胞主要为述T细胞.HCC组及对照组中T细胞受体(T cell receptor, TCR)表型一致,与丫应细胞呈显著正相关(r= 0.938,P< 0.01 );HCC组外周血CD3bright T细胞主要为CD27阴性,CD3bright CD27*T细胞比例显著低于CD27阳性的CD3*T细胞和CD4-T细胞,差异有统计学意义(P< 0.05);HCC组CD3bright CD27,T细胞比例显著低于对照组(P<0.05),CD3bright PD1-T细胞显著髙于对照组,差异有统计学意义(P< 0.05);HCC组治疗前后,常规T细胞CD27与PD1的表达水平无明显变化,CD3bright CD27-T细胞和CD3bright PDPT细胞在术后水平均显著升高,差异有统计学意义(P<0.05)o结论CD3bright T细胞主要为yST细胞,与-y6T细胞呈显著正相关,可在一定程度上反映外周血y$T细胞的水平。HCC患者外周血中,常规T细胞主要为CD27*T细胞,CD3brightT细胞主要表现为CD27阴性。CD3bright CD27,T细胞和CD3bright PD1-T细胞水平在肝癌术后显著上升,细胞活性及功能发生变化,影响HCC的进展与预后。 展开更多
关键词 肝细胞癌 CD3bright T细胞 CD27 PD 1
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Comparison of the Bright Band Characteristics Measured by Micro Rain Radar (MRR) at a Mountain and a Coastal Site in South Korea 被引量:8
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作者 Joo-Wan CHA Ki-Ho CHANG +1 位作者 Seong Soo YUM Young-Jean CHOI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第2期211-221,共11页
Data from a long term measurement of Micro Rain Radar (MRR) at a mountain site (Daegwallyeong, DG, one year period of 2005) and a coastal site (Haenam, HN, three years 2004-2006) in South Korea were analyzed to ... Data from a long term measurement of Micro Rain Radar (MRR) at a mountain site (Daegwallyeong, DG, one year period of 2005) and a coastal site (Haenam, HN, three years 2004-2006) in South Korea were analyzed to compare the MRR measured bright band characteristics of stratiform precipitation at the two sites. On average, the bright band was somewhat thicker and the sharpness (average gradient of reflectivity above and below the reflectivity peak) was slightly weaker at DG, compared to those values at HN. The peak reflectivity itself was twice as strong and the relative location of the peak reflectivity within the bright band was higher at HN than at DG. Importantly, the variability of these values was much larger at HN than at DG. The key parameter to cause these differences is suggested to be the difference of the snow particle densities at the two sites, which is related to the degree of riming. Therefore, it is speculated that the cloud microphysical processes at HN may have varied significantly from un-rimed snow growth, producing low density snow particles, to the riming of higher density particles, while snow particle growth at DG was more consistently affected by the riming process, and therefore high density snow particles. Forced uplifting of cloudy air over the mountain area around DG might have resulted in an orographic supercooling effect that led to the enhanced riming of supercooled cloud drops. 展开更多
关键词 Micro Rain Radar bright band thickness and sharpness cloud microphysical processes local characteristics
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Color-stable,reduced efficiency roll-off hybrid white organic light emitting diodes with ultra high brightness 被引量:4
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作者 刘佰全 陶洪 +4 位作者 苏跃举 高栋雨 兰林锋 邹建华 彭俊彪 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期450-453,共4页
High-brightness and color-stable two-wavelength hybrid white organic light emitting diodes (HWOLEDs) with the configuration of indium tin oxide (ITO)/ N, N, N, N-tetrakis(4-methoxyphenyl)-benzidine (MeO-TPD):... High-brightness and color-stable two-wavelength hybrid white organic light emitting diodes (HWOLEDs) with the configuration of indium tin oxide (ITO)/ N, N, N, N-tetrakis(4-methoxyphenyl)-benzidine (MeO-TPD): tetrafluoro-tetracyanoqino dimethane (F4-TCNQ)/N,N-di(naphthalene-1-yl)-N,N-diphenyl-benzidine (NPB)/ 4,4-N,N-dicarbazolebiphenyl (CBP): iridium (III) diazine complexes (MPPZ) 2 Ir(acac)/NPB/2-methyl-9,10-di(2-naphthyl)anthracene (MADN): p-bis(p-N,N-di-phenyl-aminostyryl)benzene (DSA-ph)/bis(10-hydroxybenzo[h] quino-linato)beryllium complex (Bebq2)/LiF/Al have been fabricated and characterized. The optimal brightness of the device is 69932 cd/m2 at a voltage of 13 V, and the Commission Internationale de l’Eclairage (CIE) chromaticity coordinates are almost constant during a large voltage change of 6–12 V. Furthermore, a current efficiency of 15.3 cd/A at an illumination-relevant brightness of 1000 cd/m2 is obtained, which rolls off slightly to 13.0 cd/A at an ultra high brightness of 50000 cd/m2. We attribute this great performance to wisely selecting an appropriate spacer together with effectively utilizing the combinations of exciton-harvested orange-phosphorescence/blue-fluorescence in the device. Undoubtedly, this is one of the most exciting results in two-wavelength HWOLEDs up to now. 展开更多
关键词 white light color stability efficiency roll-off high brightness
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GE Bright Speed 16排螺旋CT维修分析 被引量:1
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作者 曲传强 吴居娟 《中国保健营养(下半月)》 2012年第5期1677-1678,共2页
本文针对工作实践中对GE Bright Speed 16排螺旋CT设备出现的问题提出了对应的处理对策,以期对同行设备管理、维护、维修起到一定借鉴作用。
关键词 GE bright SPEED 16排螺旋CT 维修 处理对策
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Increase of brightness and transmission efficiency in fiat panel display through serial synchronous scanning mode with double buffers 被引量:4
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作者 陈章进 陈峰 +2 位作者 冉峰 徐美华 郑方 《Journal of Shanghai University(English Edition)》 CAS 2007年第3期314-317,共4页
This paper presents a serial synchronous scanning mode in fiat panel display (FPD) by adding a latch buffer between the serializer and the driving buffer. Comparing with conventional techniques, the proposed structu... This paper presents a serial synchronous scanning mode in fiat panel display (FPD) by adding a latch buffer between the serializer and the driving buffer. Comparing with conventional techniques, the proposed structure can efficiently reduce the brightness loss and improve the transmission performance. Theoretical analysis and experimental results show that the ratio between the lightest weight display time and the relative transmission time is a tradeoff between brightness loss and transmission efficiency. 展开更多
关键词 fiat panel display (FPD) serial scanning double buffer brightness loss transmission utilization
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Bright Blue Emission From a New Species of Polymer Diode 被引量:5
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作者 ZHANG Zhilin JIANG Xueyin +2 位作者 XU Shaohong S.Saito T.Nagamoto 《Chinese Physics Letters》 SCIE CAS CSCD 1995年第1期54-57,共4页
Blue emitting electroluminescent diode using PVCz doped with perylene and BBOT as electron transport has been constructed.The emission spectrum is a mixture of spectra of BBOT and perylene.A luminance of as high as 68... Blue emitting electroluminescent diode using PVCz doped with perylene and BBOT as electron transport has been constructed.The emission spectrum is a mixture of spectra of BBOT and perylene.A luminance of as high as 680cd/m^(2)with lumen efficiency more then 0.0281m/W have been obtained. 展开更多
关键词 DIODE ELECTROLUMINESCENT bright
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Verification and recalibration of HY-2A microwave radiometer brightness temperature 被引量:2
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作者 ZHAO Yili LI Huimin +1 位作者 CHEN Chuntao ZHU Jianhua 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第3期968-981,共14页
HY-2A is the first one of the Chinese HY-2 ocean satellite series carrying a microwave radiometer(RM)to measure sea surface temperature,sea surface wind speed,atmospheric water vapor,cloud liquid water content,and rai... HY-2A is the first one of the Chinese HY-2 ocean satellite series carrying a microwave radiometer(RM)to measure sea surface temperature,sea surface wind speed,atmospheric water vapor,cloud liquid water content,and rain rate.We verified the RM level 1B brightness temperature(T B)to retrieve environmental parameters.In the verification,TB that simulated using the ocean-atmosphere radiative transfer model(RTM)was used as a reference.The total bias and total standard deviation(SD)of the RM level 1B TB,with reference to the RTM simulation,ranged-20.6-4.38 K and 0.7-2.93 K,respectively.We found that both the total bias and the total SD depend on the frequency and polarization,although the values for ascending and descending passes are different.In addition,substantial seasonal variation of the bias was found at all channels.The verification results indicate the RM has some problems regarding calibration,e.g.,correction of antenna spillover and antenna physical emission,especially for the 18.7-GHz channel.Based on error analyses,a statistical recalibration algorithm was designed and recalibration was performed for the RM level 1B TB.Validation of the recalibrated TB indicated that the quality of the recalibrated RM level 1B TB was improved significantly.The bias of the recalibrated T B at all channels was reduced to<0.4 K,seasonal variation was almost eradicated,and SD was diminished(i.e.,the SD of the 18.7-GHz channel was reduced by more than 0.5K). 展开更多
关键词 HY-2A MICROWAVE RADIOMETER brightNESS temperature(TB) VERIFICATION calibration
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Seasonal and Interannual Variations of Upper Tropospheric Water Vapor Band Brightness Temperature over the Global Monsoon Regions 被引量:2
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作者 钱维宏 朱亚芬 +1 位作者 谢安 叶谦 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1998年第3期55-63,共9页
The upper-troposphere water vapor (UTWV) band brightness temperature (BT) dataset derived from the High-resolution Infrared Radiation Sounder (HIRS) channel 12 of the National Oceanic and Atmospheric Administration (N... The upper-troposphere water vapor (UTWV) band brightness temperature (BT) dataset derived from the High-resolution Infrared Radiation Sounder (HIRS) channel 12 of the National Oceanic and Atmospheric Administration (NOAA) polar satellites from 1979 to 1995 is used to analyze the seasonal and interannual variations for the global monsoon regions. Results show that (i) there are three major regions where the UTWV band BT varies significantly with season, i.e., South Asia, the western coastal South-North America tropical region and the low-latitude African region; (ii) UTWV band BT clearly reveals the water vapor temporal/spatial features as well as the atmospheric circulation structure over the low-latitude during the monsoon onset; and (iii) there is a remarkable relationship between the interannual variation of the UTWV band BT over the monsoon regions and the sea surface temperature anomaly in the eastern equatorial Pacific. 展开更多
关键词 MONSOON Seasonal variation Interannual variability Upper tropospheric water vapor brightness temperature
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Possible thermal brightness temperature anomalies associated with the Lushan(China) M_s7.0 earthquake on 20 April 2013 被引量:2
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作者 Tao Xie Weiyu Ma 《Earthquake Science》 CSCD 2015年第1期37-47,共11页
Lushan Ms7.0 earthquake occurred in Lushan county, Ya'an city, Sichuan province of China, on 20 April 2013, and caused 196 deaths, 23 people of missing and more than 12 thousand of people injured. In order to analyze... Lushan Ms7.0 earthquake occurred in Lushan county, Ya'an city, Sichuan province of China, on 20 April 2013, and caused 196 deaths, 23 people of missing and more than 12 thousand of people injured. In order to analyze the possible seismic brightness temperature anomalies which may be associated with Lushan earthquake, daily brightness temperature data for the period from 1 June 2011 to 31 May 2013 and the geographical extent of 25°E-35°N latitude and 98°E-108°E longitude are collected from Chinese geostationary meteorological satellite FY-2E. Continuous wavelet transform method which has good resolution both in time and frequency domains is used to analyze power spectrum of brightness temperature data. The results show that the rela- tive wavelet power spectrum (RWPS) anomalies appeared since 24 January 2013 and still lasted on 19 April. Anomalies firstly appeared at the middle part of Longmenshan fault zone and gradually spread toward the southwestern part of Longmenshan fault. Anomalies also appeared along the Xianshuihe fault since about 1 March. Eventually, anomalies gathered at the intersection zone of Longmenshan and Xianshuihe faults. The anomalous areas and RWPS ampli- tude increased since the appearance of anomalies and reached maximum in late March. Anomalies attenuated with the earthquake approaching. And eventually the earthquake occurred at the southeastern edge of anomalous areas. Lushah earthquake was the only obvious geological event within the anomalous area during the time period, so the anomalous changes of RWPS are possibly associated with the earthquake. 展开更多
关键词 Lushan earthquake brightness temperatureThermal anomaly Wavelet transform Sichuan province
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Cross-calibration of brightness temperature obtained by FY-3B/MWRI using Aqua/AMSR-E data for snow depth retrieval in the Arctic 被引量:3
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作者 Haihua Chen Lele Li Lei Guan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第1期43-53,共11页
This study cross-calibrated the brightness temperatures observed in the Arctic by using the FY-3B/MWRI L1 and the Aqua/AMSR-E L2A.The monthly parameters of the cross-calibration were determined and evaluated using rob... This study cross-calibrated the brightness temperatures observed in the Arctic by using the FY-3B/MWRI L1 and the Aqua/AMSR-E L2A.The monthly parameters of the cross-calibration were determined and evaluated using robust linear regression.The snow depth in case of seasonal ice was calculated by using parameters of the crosscalibration of data from the MWRI Tb.The correlation coefficients of the H/V polarization among all channels Tb of the two sensors were higher than 0.97.The parameters of the monthly cross-calibration were useful for the snow depth retrieval using the MWRI.Data from the MWRI Tb were cross-calibrated to the AMSR-E baseline.Biases in the data of the two sensors were optimized to approximately 0 K through the cross-calibration,the standard deviations decreased significantly in the range of 1.32 K to 2.57 K,and the correlation coefficients were as high as 99%.An analysis of the statistical distributions of the histograms before and after cross-calibration indicated that the FY-3B/MWRI Tb data had been well calibrated.Furthermore,the results of the cross-calibration were evaluated by data on the daily average Tb at 18.7 GHz,23.8 GHz,and 36.5 GHz(V polarization),and at 89 GHz(H/V polarization),and were applied to the snow depths retrieval in the Arctic.The parameters of monthly cross-calibration were found to be effective in terms of correcting the daily average Tb.The results of the snow depths were compared with those of the calibrated MWRI and AMSR-E products.Biases of 0.18 cm to 0.38 cm were observed in the monthly snow depths,with the standard deviations ranging from 4.19 cm to 4.80 cm. 展开更多
关键词 FY-3B AMSR-E brightness temperature(T^(b)) CROSS-CALIBRATION snow depth ARCTIC
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The brightness reversal of submarine sand waves in “HJ-1A/B” CCD sun glitter images 被引量:2
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作者 HE Xiekai CHEN Ninghua +1 位作者 ZHANG Huaguo GUAN Weibing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第1期94-99,共6页
The brightness reversal of submarine sand waves appearing in the small satellite constellation for environ- ment and disaster monitoring and forecasting ("HJ- 1A/B") CCD sun glitter images can affect the observati... The brightness reversal of submarine sand waves appearing in the small satellite constellation for environ- ment and disaster monitoring and forecasting ("HJ- 1A/B") CCD sun glitter images can affect the observation and depth inversion of sand wave topography. The simulations of the normalized sun glitter radiance on the submarine sand waves confirm that the reversal would happen at a specific sensor viewing angle, defined as the critical angle. The difference between the calculated critical angle position and the reversal position in the image is about 1', which is excellent in agreement. Both the simulation and actual image show that sand wave crests would be indistinct at the reversal position, which may cause problems when using these sun glitter images to analyze spatial characteristics and migration of sand waves. When using the sun glitter image to obtain the depth inversion, one should take the advantage of image properties of sand waves and choose the location in between the reversal position and the brightest position. It is also necessary to pay attention to the brightness reversal when using "HI-1A/B" CCD images to analyze other oceanic features, such as internal waves, oil slicks, eddies, and ship wakes. 展开更多
关键词 "HJ-1A/B" CCD sun glitter image submarine sand waves brightness reversal Taiwan Banks
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Preparation of Reactive Bright Blue Rare Earth Dyestuffs and Their Spectra Properties 被引量:2
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作者 Liu Xiaozhen Sang Wenbin 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第z1期210-213,共4页
Reactive bright blue rare earth dyestuffs were prepared by using reactive bright blue and lanthanum oxide,praseodymium oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, dysprosium oxide, erbium... Reactive bright blue rare earth dyestuffs were prepared by using reactive bright blue and lanthanum oxide,praseodymium oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, dysprosium oxide, erbium oxide, lutetium oxide, yttrium oxide respectively for dyeing silk cloth.The degree of dyeing of reactive bright blue praseodymium and the degree of fixation of reactive bright blue gadolinium are the biggest, and 22.9% and 7 %are increased with that of reactive bright blue respectively.The spectra of reactive bright blue rare earth and reactive bright blue were studied by UV-VIS.In 200.00 ~ 800.00 nm, reactive bright blue has four absorption peaks, reactive bright blue rare earth has three absorption peaks; in 420.00 ~ 760.00 nm, reactive bright blue has two absorption peaks at 661.50 nm and 625.50 nm, respectively, and λmax is 661.50 nm; reactive bright blue rare earth has one absorption peak at 620.50, 618.00, 622.00, 623.00, 622.50, 619.50, 619.00, 621.00, 624.00, 620.00 nm adding La3+ ,Pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Dy3+, Er3+, Lu3+, Y3+respectively. 展开更多
关键词 REACTIVE bright BLUE UV-VIS absorption spectra DEGREE of DYEING DEGREE of fixation rare earths
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