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Stable carbon isotope compositions of individual light hydrocarbons in oils: New indicator of source facies and maturity
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作者 Donglin Zhang Meijun Li Rongzhen Qiao 《Geoscience Frontiers》 2025年第5期455-469,共15页
Light hydrocarbons(LHs)are key components of petroleum,and the carbon isotopes composition(δ^(13)C)of individual LHs contains a wealth of geochemical information.Forty-four oil samples from five different basins were... Light hydrocarbons(LHs)are key components of petroleum,and the carbon isotopes composition(δ^(13)C)of individual LHs contains a wealth of geochemical information.Forty-four oil samples from five different basins were analyzed using gas chromatography(GC),gas chromatography-mass spectrometry(GC–MS),and gas chromatography-isotope ratio mass spectrometry(GC-IRMS).Theδ^(13)C values of forty-three LHs were recognized and determined by comparing the GC and GC-IRMS methods.The results revealed significant differences inδ^(13)C distribution characteristics among different LH compounds.Theδ^(13)C variation of individual LHs in iso-paraffins showed the widest range,followed by cycloalkanes and aromatics,whereas theδ^(13)C variation in n-paraffins showed the narrowest range.Theδ^(13)C values of most individual LHs are primarily affected by the source facies and thermal evolution.Among them,c-1,3-dimethylcyclohexane(c-1,3DMCH)is mainly sourced from higher plants but may also form through abiotic mechanisms such as catalysis or cyclization.Theδ^(13)C values of c-1,3DMCH(δ^(13)Cc-1,3DMCH)primarily exhibit parental genetic characteristics,enabling effective distinction of oil from different source facies.Specifically,theδ^(13)Cc-1,3DMCH in marine oils,lacustrine oils,terrigenous oils,and coal-formed oils are<–22‰,from–22‰to−20.2‰,from−20.2‰to−18.4‰,and>−18.4‰,respectively.Moreover,maturity is the primary controlling factor forδ^(13)C values of 3MC7(δ^(13)C3MC7,3MC7:3-methylheptane),while the source facies serve as a secondary influence.The plot ofδ^(13)Cc-1,3DMCH andδ^(13)C3MC7 was introduced to classify source facies.Asδ^(13)Cc-1,3DMCH andδ^(13)C3MC7 increase,the source facies transits from marine to lacustrine,then terrigenous,and finally coal facies.Additionally,increasingδ^(13)C3MC7 indicates a relative increase in maturity.Therefore,theδ^(13)Cc-1,3DMCH vs.δ^(13)C3MC7 plot serves as an effective tool for distinguishing source facies and assessing relative maturity. 展开更多
关键词 light hydrocarbons Individual carbon isotope source facies MATURITY
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Shadow-Assisted Sidewall Emission for Achieving Submicron Linewidth Light Source by Using Normal UV Photolithography
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作者 Junlong Li Yanmin Guo +7 位作者 Kun Wang Wei Huang Hao Su Wenhao Li Xiongtu Zhou Yongai Zhang Tailiang Guo Chaoxing Wu 《Nano-Micro Letters》 2025年第10期49-62,共14页
Micro light sources are crucial tools for studying the interactions between light and matter at the micro/nanoscale,encompassing diverse applications across multiple disciplines.Despite numerous studies on reducing th... Micro light sources are crucial tools for studying the interactions between light and matter at the micro/nanoscale,encompassing diverse applications across multiple disciplines.Despite numerous studies on reducing the size of micro light sources and enhancing optical resolution,the efficient and simple fabrication of ultra-high-resolution micro light sources remains challenging due to its reliance on precise micro-nano processing technology and advanced processing equipment.In this study,a simple approach for the efficient fabrication of submicron light sources is proposed,namely shadow-assisted sidewall emission(SASE)technology.The SASE utilizes the widely adopted UV photolithography process,employing metal shadow modulation to precisely control the emission of light from polymer sidewalls,thereby obtaining photoluminescent light sources with submicron line widths.The SASE eliminates the need for complex and cumbersome manufacturing procedures.The effects of process parameters,including exposure dose,development time,and metal film thickness,on the linewidth of sources are investigated on detail.It is successfully demonstrated red,green,and blue submicron light sources.Finally,their potential application in the field of optical anti-counterfeiting is also demonstrated.We believe that the SASE proposed in this work provides a novel approach for the preparation and application of micro light sources. 展开更多
关键词 Submicron light source Quantum dot Photoluminescence PHOTOLITHOGRAPHY Shadow-assisted sidewall emission
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Reconfigurable microring resonators for multipurpose quantum light sources
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作者 Yuxing Du Yingwen Liu +6 位作者 ChaoWu Pingyu Zhu Chang Zhao Miaomiao Yu Yan Wang Kaikai Zhang Ping Xu 《Chinese Physics B》 2025年第7期355-363,共9页
Microring resonators(MRRs)are extensively utilized in photonic chips for generating quantum light sources and enabling high-efficiency nonlinear frequency conversion.However,conventional microrings are typically optim... Microring resonators(MRRs)are extensively utilized in photonic chips for generating quantum light sources and enabling high-efficiency nonlinear frequency conversion.However,conventional microrings are typically optimized for a single specific function,limiting their versatility in multifunctional applications.In this work,we propose a reconfigurable microring resonator architecture designed to accommodate diverse application requirements.By integrating a cascaded Mach–Zehnder interferometer(MZI)as the microring coupler,the design enables independent control of the quality factors for pump,signal and idler photons through two tunable phase shifters.This capability allows for dynamic tuning and optimization of critical performance parameters,including photon-pair generation rate(PGR),spectral purity and single photon heralding efficiency(HE).The proposed structure is implemented on a silicon photonic chip,and experimental results exhibit a wide range of tunability for these parameters,with excellent agreement with theoretical predictions.This flexible and multi-functional design offers a promising pathway for high-performance,highly integrated on-chip quantum information processing systems. 展开更多
关键词 microring resonators cascaded Mach-Zehnder interferometer quantum light sources
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New alkylbenzene parameters to identify organic matter sources for source rocks of light oils and condensates from the Tarim Basin and Beibuwan Basin
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作者 Bing-Kun Meng Dao-Fu Song +1 位作者 Yuan Chen Sheng-Bao Shi 《Petroleum Science》 2025年第1期76-89,共14页
As an important component of light hydrocarbon compounds,alkylbenzene compounds lack indicators to indicate the source of organic matter of light oils and condensates.Forty-one oil samples from the Tarim Basin and Bei... As an important component of light hydrocarbon compounds,alkylbenzene compounds lack indicators to indicate the source of organic matter of light oils and condensates.Forty-one oil samples from the Tarim Basin and Beibuwan Basin were analyzed by comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GC-TOFMS).The concentration distributions of thirteen light hydrocarbon compounds with organic matter source and sedimentary environment indication were studied.There is no significant difference in the concentrations of 1-methylpropylbenzene(MPB)in all studied oils.However,the concentrations of 2-MPB in the Tarim swamp oils are higher than that in the Beibuwan lacustrine oils and Tarim marine oils.Based on the significant concentration difference of 1-and 2-MPB in all studied oils,1-/2-MPB(MPBr)was proposed as an indicator to identify the source of organic matter in crude oils.The MPBr values greater than 1.5 indicate that the crude oil mainly comes from lower aquatic organisms,bacteria,and algae.The MPBr values greater than 1.0 and less than 1.5 indicate that crude oil was derived from the combined contributions of lower aquatic organisms,bacteria and algae,and terrestrial higher plants.The MPBr values less than 1.0 suggest that the crude oil was mainly derived from terrigenous higher plants.The MPBr values in crude oils basically are not or slightly affected by depositional environment and secondary alteration.The MPBr values can be used to infer the organic matter origin in sediments,especially for the lack of biomarkers of light oils and condensates. 展开更多
关键词 2-Methylpropylbenzene GC×GC-TOFMS Organic matter source light oils and condensates
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UV-LED对猪场水源重要病原微生物的杀灭效率及其应用研究
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作者 纪春晓 刘剑英 +4 位作者 聂祝运 王东亮 刘德权 邹忠 唐宇龙 《畜牧与兽医》 北大核心 2025年第7期89-96,共8页
旨在探讨紫外发光二极管(UV-LED)对猪场水源中重要病原微生物的灭活效率,并分析经UV-LED消杀的饮水对断奶仔猪生长性能与免疫指标的影响。通过菌落计数法测定UV-LED对副猪格拉瑟菌(Glaesserella parasuis,GPS),猪链球菌2型(Streptococcu... 旨在探讨紫外发光二极管(UV-LED)对猪场水源中重要病原微生物的灭活效率,并分析经UV-LED消杀的饮水对断奶仔猪生长性能与免疫指标的影响。通过菌落计数法测定UV-LED对副猪格拉瑟菌(Glaesserella parasuis,GPS),猪链球菌2型(Streptococcus suis serotype 2,SS2)和肠产毒素型大肠杆菌(enterotoxigenic Escherichia coli,ETEC)3种致病菌菌株的杀灭效率;培养非洲绿猴肾细胞(Vero),非洲绿猴胚胎肾细胞(Marc-145),猪肾细胞(PK-15)与猪肺泡巨噬细胞(PAM),对其分别接种伪狂犬病病毒(PRV)、猪圆环病毒2型(PCV2)、猪繁殖与呼吸综合征病毒(PRRSV)和非洲猪瘟病毒(ASFV),观察细胞病变情况,并计算其病毒滴度,作为UV-LED灭活病毒效果的评价指标;给断奶仔猪饲喂经UV-LED消杀的饮水,测定其对生长性能及血液指标的影响。结果:UV-LED对于水源中的GPS、SS2、ETEC这3种病菌均具有很强的杀灭效果,处理17 s以上时,对以上细菌的杀灭效率可达99.90%以上;对PRV、PCV2、PRRSV、ASFV这4种病毒均具有杀灭作用,但杀灭效果存在一定区别,处理17 s以上可完全灭活PRV、PCV2与PRRSV,而完全灭活ASFV需处理58 s;断奶仔猪饲喂结果表明,给予经UV-LED消杀饮水,可显著减少断奶仔猪腹泻率(P<0.05),改善肠道功能,并且可使断奶仔猪血液中白细胞数、淋巴细胞数与单核细胞数显著下降(P<0.05)。综上,UV-LED消杀处理可以有效消杀水中常见的病原微生物,减少断奶仔猪被病原微生物感染的风险,可应用于水源消毒。 展开更多
关键词 紫外发光二极管(uv-led) 猪场 水源 消毒 病原微生物
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Gas source of the Middle Jurassic Shaximiao Formation in the Zhongjiang large gas field of Western Sichuan Depression:Constraints from geochemical characteristics of light hydrocarbons 被引量:2
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作者 Xiaoqi Wu Jun Yang +4 位作者 Ping Wang Huaji Li Yingbin Chen Chunhua Ni Huasheng Zeng 《Energy Geoscience》 EI 2024年第2期141-151,共11页
The Zhongjiang gas field is a typical large gas field in terrigenous strata of the Western Sichuan Depression.It remains debatable which member of the Upper Triassic Xujiahe Formation served as the source rocks and ho... The Zhongjiang gas field is a typical large gas field in terrigenous strata of the Western Sichuan Depression.It remains debatable which member of the Upper Triassic Xujiahe Formation served as the source rocks and how significant the member contributed to the gas accumulations in the Zhongjiang gas field.In this study,we analyzed the essential characteristics of the Lower Jurassic source rocks and the geochemical features of light hydrocarbons in natural gas from the 2nd(T_(3)χ^(2))and 4th members(T_(3)χ^(4))of the Upper Triassic Xujiahe Formation(T_(3)χ),as well as the Middle Jurassic Shaximiao(J_(2)s)and Qianfoya(J_(2)q)formations.Based on this,we explored the sources of the natural gas in the Zhongjiang gas field and determined the natural gas migration patterns and their effects on the properties of light hydrocarbons in the natural gas.The results indicate that the Lower Jurassic lacustrine source rocks of the Zhongjiang gas field contain humic organic matter,with vitrinite reflectance(R_(0))values ranging from 0.86%to 0.98%.Samples meeting the criterion for effective source rocks[total organic carbon(TOC)content≥0.75%]exhibited an average TOC content of merely 1.02%,suggesting significantly lower hydrocarbon generation potential than source rocks in the underlying T3x,which show higher thermal maturity and TOC contents.For natural gas samples from T_(3)χ^(2),T_(3)χ^(4),J_(2)s,and J_(2)q reservoirs,their C_(5-7)iso-alkane content was significantly higher than their n-alkane content,and their methylcyclohexane(MCH)index ranged from 59.0%to 77.3%,indicating the predominance of methylcyclohexane in C_(7)light hydrocarbons.As indicated by the origin identification and gas-source correlation based on the geochemical features of light hydrocarbons,the natural gas in the Zhongjiang gas field is typical coal-derived gas.The gas from the primary pay zone of the Shaximiao Formation,with significantly high K_(1),(P_(2)+N_(2))/C_(7),and P_(3)/C_(7)values,predominantly originated from the 5th member of the T3x and migrated in the free phase,with a small amount possibly sourced from the Lower Jurassic source rocks.The dissolution and adsorption during gas migration led to a decrease in the aromatic content in C_(6-7)light hydrocarbons and an increase in the isoheptane values.Therefore,their effects must be considered when determining the gas origin and thermal maturity based on the aromatic content in C_(6-7) light hydrocarbons and iso-heptane values. 展开更多
关键词 Zhongjiang gas field source rock Origin of natural gas light hydrocarbon geochemistry Natural gas migration
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On-chip high-energy photon radiation source based on near-field-dielectric undulator
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作者 Fu-Ming Jiang Xin-Yu Xie +1 位作者 Chengpu Liu Ye Tian 《Advanced Photonics Nexus》 2025年第3期29-36,共8页
A new on-chip light source configuration has been proposed,which utilizes the interaction between a microwave or laser and a dielectric nanopillar array to generate a periodic electromagnetic near-field and applies pe... A new on-chip light source configuration has been proposed,which utilizes the interaction between a microwave or laser and a dielectric nanopillar array to generate a periodic electromagnetic near-field and applies periodic transverse acceleration to relativistic electrons to generate high-energy photon radiation.The dielectric nanopillar array interacting with the driving field acts as an electron undulator,in which the near-field drives electrons to oscillate.When an electron beam propagates through this nanopillar array in this light source configuration,it is subjected to a periodic transverse near-field force and will radiate X-ray or evenγ-ray high-energy photons after a relativistic frequency up-conversion.Compared with the undulator which is based on the interaction between strong lasers and nanostructures to generate a plasmonic near-field,this configuration is less prone to damage during operation. 展开更多
关键词 free-electron light source on-chip light source X-ray light source miniature undulator
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Evaluating coarse PM composition and sources based on bulk and molecular speciation of PM_(2.5) and PM_(10) in Nanjing, East China
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作者 Wangnan Cui Zishu Wang +4 位作者 Wei Feng Chao Qin Hong Liao Yuhang Wang Mingjie Xie 《Journal of Environmental Sciences》 2025年第6期155-166,共12页
To understand the differences in the composition and sources of PM_(2.5) and PM_(10) caused by coarse particles,integrated PM_(2.5) and PM_(10) samples were synchronously collected in Nanjing,East China,in summer 2020... To understand the differences in the composition and sources of PM_(2.5) and PM_(10) caused by coarse particles,integrated PM_(2.5) and PM_(10) samples were synchronously collected in Nanjing,East China,in summer 2020 and winter 2020/2021.Bulk and molecular speciation and light absorption measurements of aerosol extractswere performed,followed by positivematrix factorization(PMF)based on the PM_(2.5) and PM_(10) data sets,respectively.The difference in average concentrations of total bulk species between PM_(2.5) and PM_(10) was mainly caused by the distribution of considerable NO_(3)^(–),SO42–,Ca^(2+),and organic carbon(OC)in coarse particles.Coarse PMinfluenced by abrasion products from tirewear and leaves contributed about half of the low-volatility n-alkanes in summer.The contribution of coarse PM to biomass burning tracers and water-soluble OC increased in winter when biomass combustion was excessively active.More than 70%of sugar polyols were attributable to coarse PM in summer,and biomass burning could be an important source in winter.The light-absorbing organic chromophores were almost entirely associated with PM_(2.5),but water-soluble organic carbon(WSOC)exhibited stronger light absorption in PM_(10) extracts than in PM_(2.5) extracts possibly due to the influence of coarse PMon pH.PMF analysis indicated that biomass burning,aqueous-phase reactions,and processed dust were the main contributors of organic matter and its light absorption in winter.Biogenic primary and secondary sources made discernable contributions only in summer.The differences between PM_(2.5) and PM_(10) were likely attributed to mixing of crustal dust,combustion particles,and surface reactions. 展开更多
关键词 Coarse particle Bulk species Organic molecular marker light absorption source apportionment
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The full lifecycle management of scientific data at Hefei Light Source soft X-ray microscopy station
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作者 Haishan Yu Lei Cui +4 位作者 Zhen Zhang Guang Lin Xiaokang Sun DaDi Zhang Gongfa Liu 《中国科学技术大学学报》 CSCD 北大核心 2024年第11期2-7,1,66,共8页
Hefei Light Source(HLS)is a synchrotron radiation light source that primarily produces vacuum ultraviolet and soft X-rays.It currently consists of ten experimental stations,including a soft X-ray microscopy station.As... Hefei Light Source(HLS)is a synchrotron radiation light source that primarily produces vacuum ultraviolet and soft X-rays.It currently consists of ten experimental stations,including a soft X-ray microscopy station.As part of its on-going efforts to establish a centralized scientific data management platform,HLS is in the process of developing a test sys-tem that covers the entire lifecycle of scientific data,including data generation,acquisition,processing,analysis,and de-struction.However,the instruments used in the soft X-ray microscopy experimental station rely on commercial propriet-ary software for data acquisition and processing.We developed a semi-automatic data acquisition program to facilitate the integration of soft X-ray microscopy stations into a centralized scientific data management platform.Additionally,we cre-ated an online data processing platform to assist users in analyzing their scientific data.The system we developed and de-ployed meets the design requirements,successfully integrating the soft X-ray microscopy station into the full lifecycle management of scientific data. 展开更多
关键词 Hefei light source soft X-ray microscopy full lifecycle data acquisition data processing scientific data
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Metamerism Appreciation of Jadeite-Jade Green under the Standard Light Sources D_(65),A and CWF 被引量:6
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作者 GUO Ying WANG Huan +1 位作者 LI Xiang DONG Shirong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2097-2103,共7页
We tested 288 pieces of the polished cabochon jadeite-jade with high quality green and smooth surfaces using the colorimeter Color i5 based on the CIE 1976 L*a*b* uniform color space. The color changes after altern... We tested 288 pieces of the polished cabochon jadeite-jade with high quality green and smooth surfaces using the colorimeter Color i5 based on the CIE 1976 L*a*b* uniform color space. The color changes after alternating three CIE standard light sources D65, A and CWF were compared, and the degree of metamerism was evaluated. The results show that the CIE standard light sources D65, A and CWF increase the chroma of green and turn bluish green into vivid green, which are similar or to nearly colorless and transparent glass-like samples with fine textures. When the three light sources were individually alternated, the lightness of the jadeite-jades showed little change, but the tone changed significantly. Metamerism occurred only in 3 pairs among the 16 samples that were selected by cluster analysis for quality, and the metamerism colors were highly consistent of L*D65∈(43.47, 46.75), C*D65∈(65.20, 68.80) and ho*D65∈(138.10, 140.23). We can conclude that the jadeite-jade green gradually turns to blue when the color temperature of the light source increases. But when considering both the light sources and the samples, D65 is more suitable to be the light source of jadeite-jade green when compared with the light sources CWF and A. Compared with the CIE standard green and high chroma green, high-quality jadeite-jade green has a slight yellow tone, low lightness and high chroma. The special metamerism index decreased to 1 when the light source alternated among D65, A and CWF. Therefore, the color of jadeite-jade green might be slightly influenced by alternating of the light sources. 展开更多
关键词 Jadeite-Jade green CIE standard light source light source alteration special metamerism index
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Early gastric cancer diagnostic ability of ultrathin endoscope loaded with laser light source 被引量:7
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作者 Takuto Suzuki Yoshiyasu Kitagawa +1 位作者 Rino Nankinzan Taketo Yamaguchi 《World Journal of Gastroenterology》 SCIE CAS 2019年第11期1378-1386,共9页
BACKGROUND Conventionally, the low luminous intensity, low image resolution, and difficulty in operation have been reported with the ultrathin endoscope. However, it has markedly advanced recently. The improvement of ... BACKGROUND Conventionally, the low luminous intensity, low image resolution, and difficulty in operation have been reported with the ultrathin endoscope. However, it has markedly advanced recently. The improvement of the diagnostic ability is expected.AIM To compare the early gastric cancer diagnostic ability of an ultrathin endoscope loaded with a laser light source and that of the conventional endoscope.METHODS The target subjects were 375 consecutive patients who underwent endoscopy at our hospital for post-endoscopic submucosal dissection follow-up of gastric cancer from January to August 2018. During endoscopy, the ultrathin endoscope was used in 140 patients(37.3%), and the conventional endoscope was used in235 patients(62.7%). Patient background was adjusted using the propensity score matching method, and gastric cancer detection ability was evaluated in the two groups.RESULTS The gastric cancer detection rate was 7.8% in the ultrathin endoscope group and7.0% in the conventional endoscope group, and the mean intragastric observation time was 4.1 ± 1.7 min in the ultrathin endoscope group and 4.1 ± 1.9 min in the conventional endoscope group, showing no significant differences between the groups. Moreover, the biopsy implementation rate was 31.8% in the ultrathin endoscope group and 41.1% in the conventional endoscope group, and the biopsy prediction rate was 17.9% and 13.2%, respectively, showing no significant differences between the groups.CONCLUSION The gastric cancer diagnostic ability of the ultrathin endoscope loaded with a laser light source was comparable to that of the conventional endoscope. The observation time was also comparable. Thus, endoscopy using the ultrathin endoscope loaded with the laser light source would be the first option in screening examinations of gastric cancer due to its low invasion. 展开更多
关键词 CONVENTIONAL ENDOSCOPE GASTRIC cancer LASER light source Screening ULTRATHIN ENDOSCOPE
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Light absorption properties and potential sources of brown carbon in Fenwei Plain during winter 2018–2019 被引量:8
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作者 Wenyu Zhang Weigang Wang +10 位作者 Jie Li Shuangliang Ma Chaofan Lian Kun Li Bo Shi Mingyuan Liu Yanyu Li QingQing Wang Yele Sun Shengrui Tong Maofa Ge 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第4期53-63,共11页
A distinctive kind of organic carbon aerosol that could absorb ultraviolet-visible radiation is called brown carbon(Br C),which has an important positive influence on radiative budget and climate change.In this work,w... A distinctive kind of organic carbon aerosol that could absorb ultraviolet-visible radiation is called brown carbon(Br C),which has an important positive influence on radiative budget and climate change.In this work,we reported the absorption properties and potential source of Br C based on a seven-wavelength aethalometer in the winter of 2018–2019 at an urban site of Sanmenxia in Fenwei Plain in central China.Specifically,the mean value of Br C absorption coefficient was 59.6±36.0 Mm^(-1) at 370 nm and contributed 37.7%to total absorption,which made a significant impact on visibility and regional environment.Absorption coefficients of Br C showed double-peak pattern,and Br C had shown small fluctuations under haze days compared with clean days.As for the sources of Br C,Br C absorption coefficients expressed strong correlations with element carbon aerosols and primary organic carbon aerosols,indicating that most of Br C originated from primary emissions.The linear correlations between trace metal elements(K,As,Fe,Mn,Zn,and Pb)and Br C absorption coefficients further referred that the major sources of Br C were primary emissions,like coal burning,biomass burning,and vehicle emissions.The moderate relationship between Br C absorption coefficients and secondary organic aerosols suggested that secondary production of Br C also played an important role.The 120 hr backward air mass trajectories analysis and concentration-weighted trajectories analysis were also used to investigate potential sources of Br C in and around this area,which inferred most parts of Br C were derived from local emissions. 展开更多
关键词 Brown carbon light absorption Potential source analysis Fenwei Plain
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Fast recognition using convolutional neural network for the coal particle density range based on images captured under multiple light sources 被引量:6
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作者 Feiyan Bai Minqiang Fan +1 位作者 Hongli Yang Lianping Dong 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第6期1053-1061,共9页
A method based on multiple images captured under different light sources at different incident angles was developed to recognize the coal density range in this study.The innovation is that two new images were construc... A method based on multiple images captured under different light sources at different incident angles was developed to recognize the coal density range in this study.The innovation is that two new images were constructed based on images captured under four single light sources.Reconstruction image 1 was constructed by fusing greyscale versions of the original images into one image,and Reconstruction image2 was constructed based on the differences between the images captured under the different light sources.Subsequently,the four original images and two reconstructed images were input into the convolutional neural network AlexNet to recognize the density range in three cases:-1.5(clean coal) and+1.5 g/cm^(3)(non-clean coal);-1.8(non-gangue) and+1.8 g/cm^(3)(gangue);-1.5(clean coal),1.5-1.8(middlings),and+1.8 g/cm^(3)(gangue).The results show the following:(1) The reconstructed images,especially Reconstruction image 2,can effectively improve the recognition accuracy for the coal density range compared with images captured under single light source.(2) The recognition accuracies for gangue and non-gangue,clean coal and non-clean coal,and clean coal,middlings,and gangue reached88.44%,86.72% and 77.08%,respectively.(3) The recognition accuracy increases as the density moves further away from the boundary density. 展开更多
关键词 COAL Density range Image Multiple light sources Convolutional neural network
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Adaptive illumination light source for online machine vision inspection of tin steel strips 被引量:3
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作者 PENG Tiegen HE Yonghui 《Baosteel Technical Research》 CAS 2013年第4期25-28,共4页
The different reflection characteristics of the surface of tin steel strips and the different speeds of the tinning line demand an adaptive illumination light source for online machine vision inspection. This light so... The different reflection characteristics of the surface of tin steel strips and the different speeds of the tinning line demand an adaptive illumination light source for online machine vision inspection. This light source can be integrated with a time delay integration charge-coupled device (TDI CCD ) to capture the images of moving objects and facilitate inspection of the surface quality of tin steel strips. On-site application show the effectiveness of the TDI camera with the adaptive illumination light source in detecting the surface defects on tin steel strips of three different materials and with different tin coating weights. 展开更多
关键词 adaptive illumination light source tin steel strip TDI camera
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Optimization management of hybrid energy source of fuel cell truck based on model predictive control using traffic light information 被引量:2
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作者 Qiuyi GUO Zhiguo ZHAO +1 位作者 Peihong SHEN Peidong ZHOU 《Control Theory and Technology》 EI CSCD 2019年第4期309-324,共16页
Energy optimization management can make fuel cell truck(FCT)power system more efficient,so as to improve vehicle fuel economy.When the structure of power source system and the torque distribution strategy are determin... Energy optimization management can make fuel cell truck(FCT)power system more efficient,so as to improve vehicle fuel economy.When the structure of power source system and the torque distribution strategy are determined,the essence is to find the reasonable distribution of electric power between the fuel cell and other energy sources.The paper simulates the assistance of the intelligent transport system(ITS)and carries out the eco-velocity planning using the traffic signal light.On this basis,in order to further improve the energy efficiency of FCT,a model predictive control(MPC)-based energy source optimization management strategy is innovatively developed,which uses Dijkstra algorithm to achieve the minimization of equivalent hydrogen consumption.Under the scenarios of signalized intersections,based on the planned eco-velocity,the off-line simulation results show that the proposed MPC-based energy source management strategy(ESMS)can reduce hydrogen consumption of fuel cell up to 7%compared with the existing rule-based ESMS.Finally,the Hardware-in-the-Loop(HiL)simulation test is carried out to verify the effectiveness and real-time performance of the proposed MPC-based energy source optimization management strategy for the FCT based on eco-velocity planning with the assistance of traffic light information. 展开更多
关键词 Fuel cell truck hybrid energy source management strategy model predictive control traffic light
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An indoor calibration light source of the transmissometers based on spatial light modulation 被引量:1
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作者 LIANG Jing ZHANG Guoyu +3 位作者 ZHANG Jian XU Da CHONG Wei SUN Jiliang 《Optoelectronics Letters》 EI 2022年第2期65-71,共7页
Aiming at the problem that the calibration results of the transmissometers cannot be traced to the meteorological optical range(MOR) defined by the World Meteorological Organization(WMO). We designed an indoor calibra... Aiming at the problem that the calibration results of the transmissometers cannot be traced to the meteorological optical range(MOR) defined by the World Meteorological Organization(WMO). We designed an indoor calibration light source of the transmissometers based on spatial light modulation, focusing on the design of a non-intersecting CzernyTurner spectroscopic system which achieved a spectral resolution of less than 1 nm in the range from 380 nm to 780 nm. Then, the calibration light source’s spectrum matching model is established and the digital micromirror device(DMD)’s surface illuminance distribution law is simulated and analyzed. Finally, the MOR error of the calibrated light source is inverted. The results show that the simulation spectrum error of the 2 700 K absolute color temperature is below ±7.4% in the wavelength range from 380 nm to 780 nm, and the MOR error meets the requirements of the International Civil Aviation Organization in 40-2 000 m of MOR. 展开更多
关键词 source light ERROR
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Light absorption distribution of prostate tissue irradiated by diffusing light source 被引量:1
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作者 彭东青 谢文明 +3 位作者 郭建 唐嘉铭 李志芳 李晖 《Optoelectronics Letters》 EI 2015年第3期237-240,共4页
Determination of light absorption distribution in the prostate tissue irradiated by diffusing light source is important for the treatment planning.In this paper,a three-dimensional(3D)optical model of human prostate i... Determination of light absorption distribution in the prostate tissue irradiated by diffusing light source is important for the treatment planning.In this paper,a three-dimensional(3D)optical model of human prostate is developed,and the light absorption distribution in the prostate tissue is estimated by Monte Carlo simulation method.Light distribution patterns including 3D distributions in the tissue model irradiated by two diffusing light sources are obtained and compared.Also,the impacts of length and energy of cylinder diffusing light source on the irradiance volume are demonstrated.Those results will be significant for the nondestructive qualitative assessments of photodosimetry in biomedical phototherapy. 展开更多
关键词 Electromagnetic wave absorption Intelligent systems light absorption light sources Monte Carlo methods UROLOGY
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Watts-level ultraviolet-CLED integrated light sources for efficient surface and air sterilization 被引量:1
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作者 Wei Luo Tai Li +7 位作者 Yongde Li Houjin Wang Ye Yuan Shangfeng Liu Weiyun Wang Qi Wang Junjie Kang Xinqiang Wang 《Journal of Semiconductors》 EI CAS CSCD 2022年第7期61-67,共7页
With the epidemic of the coronavirus disease(COVID-19) infection, AlGaN-based ultraviolet-C light emitting diodes(UVC-LEDs) have attracted widespread attention for their sterilization application. However, the sterili... With the epidemic of the coronavirus disease(COVID-19) infection, AlGaN-based ultraviolet-C light emitting diodes(UVC-LEDs) have attracted widespread attention for their sterilization application. However, the sterilization characters of high power integrated light sources(ILSs) haven’t been widely investigated before utilizing in public sanitary security. In this work,by integrating up to 195 UVC-LED chips, high power UVC-LED ILSs with a light output power(LOP) of 1.88 W were demonstrated. The UVC-LED ILSs were verified to have efficient and rapid sterilization capability, which have achieved more than99.9% inactivation rate of several common pathogenic microorganisms within 1 s. In addition, the corresponding air sterilization module based on them was also demonstrated to kill more than 97% of Staphylococcus albus in the air of 20 m3 confined room within 30 min. This work demonstrates excellent sterilization ability of UVC-LED ILSs with high LOP, revealing great potential of UVC-LEDs in sterilization applications in the future. 展开更多
关键词 ultraviolet-C LED integrated light source surface sterilization air sterilization
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Quantum light source devices of In(Ga)As semiconductor self-assembled quantum dots
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作者 Xiaowu He Yifeng Song +15 位作者 Ying Yu Ben Ma Zesheng Chen Xiangjun Shang Haiqiao Ni Baoquan Sun Xiuming Dou Hao Chen Hongyue Hao Tongtong Qi Shushan Huang Hanqing Liu Xiangbin Su Xinliang Su Yujun Shi Zhichuan Niu 《Journal of Semiconductors》 EI CAS CSCD 2019年第7期27-37,共11页
A brief introduction of semiconductor self-assembled quantum dots (QDs) applied in single-photon sources is given. Single QDs in confined quantum optical microcavity systems are reviewed along with their optical prope... A brief introduction of semiconductor self-assembled quantum dots (QDs) applied in single-photon sources is given. Single QDs in confined quantum optical microcavity systems are reviewed along with their optical properties and coupling characteristics. Subsequently, the recent progresses in In(Ga)As QDs systems are summarized including the preparation of quantum light sources, multiple methods for embedding single QDs into different microcavities and the scalability of single-photon emitting wavelength. Particularly, several In(Ga)As QD single-photon devices are surveyed including In(Ga)As QDs coupling with nanowires, InAs QDs coupling with distributed Bragg reflection microcavity and the In(Ga)As QDs coupling with micropillar microcavities. Furthermore, applications in the field of single QDs technology are illustrated, such as the entangled photon emission by spontaneous parametric down conversion, the single-photon quantum storage, the chip preparation of single-photon sources as well as the single-photon resonance-fluorescence measurements. 展开更多
关键词 QUANTUM OPTICS QUANTUM DOTS NANOWIRES light sourceS
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生产过程中应用UV-LED光源在线检测迷迭香酸含量的研究
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作者 张学亮 周冬丽 +2 位作者 李明明 袁志建 吉桂珍 《中国食品添加剂》 CAS 2024年第9期229-233,共5页
本研究采用275~285 nm波段的UV-LED灯替代氘灯作为迷迭香酸含量检测的单波长光源,优化电路设计,自制UV-LED光源。经验证,光源的性能参数:20 min内280 nm波长下的基线最大漂移量为0.005;波长日内波动绝对差值≤0.414 nm,日间波动绝对差值... 本研究采用275~285 nm波段的UV-LED灯替代氘灯作为迷迭香酸含量检测的单波长光源,优化电路设计,自制UV-LED光源。经验证,光源的性能参数:20 min内280 nm波长下的基线最大漂移量为0.005;波长日内波动绝对差值≤0.414 nm,日间波动绝对差值≤0.827 nm;吸光度日内波动绝对差值≤0.023,波长日间波动绝对差值≤0.039;3天内280 nm波长下的光强波动幅度在2%以内,吸光度波动幅度低于0.008。针对迷迭香酸溶液,经验证UV-LED光源检测结果与氘灯光源检测结果线性相关系数0.99以上,并将UV-LED光源成功应用于在线判定迷迭香酸生产最佳吸附饱和点检测,解决了氘灯光源寿命短、在线检测运行成本高等难题。且自制UV-LED光源光强可调,扩大了光纤光谱仪应用范围,这有助于推动企业实现自动化、数字化的进程。 展开更多
关键词 迷迭香酸 光纤光谱仪 uv-led光源 在线检测
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