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Ambient photolysis frequency of NO

Qi Zou,Keding Lu,Yusheng Wu,Yudong Yang,Zhuofei Du,Min Hu

《环境科学与工程前沿（英文）》 2016年 第10卷 第6期 doi: 10.1007/s11783-016-0885-3

摘要： • Chemical actinometer (CA) was built for NO photolysis frequency, j(NO ), analysis. • CA data (10% accuracy) were compared with spectroradiometer (SR) data. • Long-term j(NO ) measurement was validated by comparison of CA and SR. • Dis-benefit of aerosol on j(NO ) due toparticulate matter (PM ) control on O . The photolysis frequency of NO , j(NO ), is an important analytical parameter in the study of tropospheric chemistry. A chemical actinometer (CA) was built to measure the ambient j(NO ) based on a high precision NO instrument with 1 min time resolution. Parallel measurements of the ambient j(NO ) by using the CA and a commercial spectroradiometer (SR) were conducted at a typical urban site (Peking University Urban Environmental Monitoring Station) in Beijing. In general, good agreement was achieved between the CA and SR data with a high linear correlation coefficient ( = 0.977) and a regression slope of 1.12. The regression offset was negligible compared to the measured signal level. The j(NO ) data were calculated using the tropospheric ultraviolet visible radiation (TUV) model, which was constrained to observe aerosol optical properties. The calculated j(NO ) was intermediate between the results obtained with CA and SR, demonstrating the consistency of all the parameters observed at this site. The good agreement between the CA and SR data, and the consistency with the TUV model results, demonstrate the good performance of the installed SR instrument. Since a drift of the SR sensitivity is expected by the manufacturer, we propose a regular check of the data acquired via SR against those obtained by CA for long-term delivery of a high quality series of j(NO ) data. Establishing such a time series will be invaluable for analyzing the long-term atmospheric oxidation capacity trends as well as O pollution for urban Beijing.

关键词： Photolysis frequency of nitrogen dioxide     Chemical actinometer     Spectroradiometer     Tropospheric ultraviolet visible radiation model    

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Theoretical study on flow and radiation in tubular solar photocatalytic reactor

《能源前沿（英文）》 2021年 第15卷 第3期   页码 687-699 doi: 10.1007/s11708-021-0773-9

摘要： In this paper, based on the mixture flow model, an optimized six-flux model is first established and applied to the tubular solar photocatalytic reactor. Parameters influencing photocatalyst distribution and radiation distribution at the reactor outlet, viz. catalyst concentration and circulation speed, are also analyzed. It is found that, at the outlet of the reactor, the optimized six-flux model has better performances (the energy increase by 1900% and 284%, respectively) with a higher catalyst concentration (triple) and a lower speed (one third).

关键词： photocatalytic hydrogen photoreactor     nume- rical simulation     solar energy     flow model     radiation model    

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Photodegradation of chromophoric dissolved organic matters in the water of Lake Dianchi, China

Yuan ZHANG,Chunming HU,Tao YU

《环境科学与工程前沿（英文）》 2015年 第9卷 第4期   页码 575-582 doi: 10.1007/s11783-014-0664-y

摘要： Water samples were taken from Lake Dianchi, on the Yungui Plateau of southwest China, and experiments were conducted to simulate the photochemical degradation characteristic of chromophoric dissolved organic matter (CDOM) in the lake water. Three groups of experiments under different light conditions: ultraviolet (UV) light, visible light, and dark, were done and variations of fluorescence properties, UV absorbance, and dissolved organic carbon (DOC) concentrations during the experiments were analyzed to study the photodegradation process of CDOM with time. The result showed that light irradiation led to significant photochemical degradation of CDOM, resulting in changes in florescent properties, absorbance losses, decreases in aromaticity and average molecular weight, as well as decline in DOC concentration in the water. It was also observed that UV irradiation had greater effect than visible light did. However, various fluorophores had different sensitivities to the same irradiation condition, that is, protein-like fluorophore at the low excitation wavelengths is more sensitive to UV irradiation than the other fluorophores, and is more readily to undergo photo-degradation. In addition, visible light irradiation did not have significant impact on DOC in the water, with DOC concentration decrease by 5.57% –59.9% during the experiment time. These results may provide new knowledge on the environment behavior of CDOM in the water of Lake Dianchi.

关键词： chromophoric dissolved organic matter     photodegradation     ultraviolet radiation     dissolved organic carbon    

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Preparation and characterization of polyimide/silica/silver composite films

JIANG Lizhong, WU Dezhen, LUO Ning, WU Zhanpeng, MOU Nanxiang

《化学科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 291-295 doi: 10.1007/s11705-008-0059-3

摘要： Polyimide/silica/silver hybrid films were prepared by the sol-gel method combined with single-stage self-metallization technique. The structure of polyimide films in the thermal curing process and the influence of silica content on the migration and aggregation of silver particles to the surface of hybrid films were investigated. The hybrid films were characterized by transmission electron microscopy, dynamic mechanical thermal analysis, Fourier transform infrared spectroscopy, ultraviolet visible spectroscopy and mechanical measurements. The results indicated that there was no degradation of the polyimide matrix after the formation of silica and silver particles. Silica acted as the nucleus for the silver particles. With increasing silica content, more and more silver particles were kept in the hybrid films instead of being migrated onto the surface of the hybrid films and the reflections of hybrid films decreased gradually.

关键词： single-stage self-metallization     spectroscopy     transmission     Polyimide/silica/silver     ultraviolet visible    

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Is atmospheric oxidation capacity better in indicating tropospheric O formation?

《环境科学与工程前沿（英文）》 2022年 第16卷 第5期 doi: 10.1007/s11783-022-1544-5

摘要：

● This study summarizes and evaluates different approaches that indicate O3 formation.

关键词： O3     AOC     O3 formation regime    

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Review on the applications of Tropospheric Emissions Spectrometer to air-quality research: Perspectives

Yuxuan WANG, Yuqiang ZHANG, Jiming HAO,

《环境科学与工程前沿（英文）》 2010年 第4卷 第1期   页码 12-19 doi: 10.1007/s11783-010-0012-9

摘要： The Tropospheric Emissions Spectrometer (TES) aboard the National Aeronautics and Space Administration’s (NASA’s) Aura satellite launched in July 2004 is the first satellite instrument to provide simultaneous retrievals of ozone (O) and carbon monoxide (CO) throughout the Earth’s lower atmosphere. This paper briefly reviews the TES instrument, the retrieval of O and CO profiles, and the validation of the retrievals. The applications of TES O and CO products include mapping the vertical and horizontal distribution of tropospheric O and CO and their correlations, examining the regional and continental outflow, and analyzing the variability of the two species associated with certain weather and climatic conditions, such as El Niño and the Asian monsoon. TES retrievals of O and CO offer an important new source of satellite data over China with good spatial and temporal coverage that can provide evaluation and constraints on the performance of chemical transport models in simulating the general features of ozone pollution over China. Special observations have been conducted and requests may be submitted to the TES team to make geographically focused observations of O and CO over China.

关键词： Tropospheric Emissions Spectrometer (TES)     ozone     carbon monoxide     China    

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A method of determining flame radiation fraction induced by interaction burning of tri-symmetric propanefires in open space based on weighted multi-point source model

Jie JI, Junrui DUAN, Huaxian WAN

《能源前沿（英文）》 2022年 第16卷 第6期   页码 1017-1026 doi: 10.1007/s11708-020-0716-x

摘要： The interaction of multiple fires may lead to a higher flame height and more intense radiation flux than a single fire, which increases the possibility of flame spread and risks to the surroundings. Experiments were conducted using three burners with identical heat release rates (HRRs) and propane as the fuel at various spacings. The results show that flames change from non-merging to merging as the spacing decreases, which result in a complex evolution of flame height and merging point height. To facilitate the analysis, a novel merging criterion based on the dimensionless spacing / was proposed. For non-merging flames ( / >0.368), the flame height is almost identical to a single fire; for merging flames ( / ≤0.368), based on the relationship between thermal buoyancy and thrust (the pressure difference between the inside and outside of the flame), a quantitative analysis of the flame height, merging point height, and air entrainment was formed, and the calculated merging flame heights show a good agreement with the measured experimental values. Moreover, the multi-point source model was further improved, and radiation fraction of propane was calculated. The data obtained in this study would play an important role in calculating the external radiation of propane fire.

关键词： flame interaction     air entrainment     flame height     multi-point source model     thermal radiation    

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Nongray radiation from gas and soot mixtures in planar plates based on statistical narrow-band spectralmodel

Huaqiang CHU, Qiang CHENG, Huaichun ZHOU, Fengshan LIU

《能源前沿（英文）》 2011年 第5卷 第2期   页码 149-158 doi: 10.1007/s11708-010-0124-8

摘要： The nongray behavior of combustion products plays an important role in various areas of engineering. Based on the statistical narrow-band (SNB) spectral model with an exponential-tailed inverse intensity distribution and the ray-tracing method, a comprehensive investigation of the influence of soot on nongray radiation from mixtures containing H O/N +soot, CO /N +soot, or H O/CO /N +soot was conducted in this paper. In combustion applications, radiation transfer is significantly enhanced by soot due to its spectrally continuous emission. The effect of soot volume fraction up to 1×10 on the source term, the narrow-band radiation intensities along a line-of-sight, and the net wall heat fluxes were investigated for a wide range of temperature. The effect of soot was significant and became increasingly drastic with the increase of soot loading.

关键词： soot     combustion     SNB model     nongray radiation    

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Smart model for accurate estimation of solar radiation

Lazhar ACHOUR, Malek BOUHARKAT, Ouarda ASSAS, Omar BEHAR

《能源前沿（英文）》 2020年 第14卷 第2期   页码 383-399 doi: 10.1007/s11708-017-0505-3

摘要： Prediction of solar radiation has drawn increasing attention in the recent years. This is because of the lack of solar radiation measurement stations. In the present work, 14 solar radiation models have been used to assess monthly global solar radiation on a horizontal surface as function of three parameters: extraterrestrial solar irradiance ( ), duration sunshine ( ) and daylight hours ( ). Since it has been observed that each model is adequate for some months of the year, one model cannot be used for the prediction of the whole year. Therefore, a smart hybrid system is proposed which selects, based on the intelligent rules, the most suitable prediction model of the 14 models listed in this study. For the test and evaluation of the proposed models, Tamanrasset city, which is located in the south of Algeria, is selected for this study. The meteorological data sets of five years (2000–2004) have been collected from the Algerian National Office of Meteorology (NOM), and two spatial databases. The results indicate that the new hybrid model is capable of predicting the monthly global solar radiation, which offers an excellent measuring accuracy of values ranging from 93% to 97% in this location.

关键词： global solar radiation     statistical indicator     hybrid model     spatial database     correlation coefficients    

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Ultraviolet exposure enhanced silicon direct bonding

Guanglan LIAO, Xuekun ZHANG, Xiaohui LIN, Canghai MA, Lei NIE, Tielin SHI,

《机械工程前沿（英文）》 2010年 第5卷 第1期   页码 87-92 doi: 10.1007/s11465-009-0078-x

摘要： Ultraviolet (UV) exposure, as an additional technique following the traditional wet chemical activation processes, is applied to enhance hydrophilic silicon direct bonding. The effects of UV exposure on silicon wafers’ nano-topography and bonding strength are studied. It is found that the surface roughness of silicon wafers initially decreases and then increases with UV exposure time, and the bonding strength increases and then decreases accordingly. The correlations of annealing temperature and annealing time vs. bonding strength are experimentally explored. Results indicate that the bonding strength increases sharply then gently with increasing annealing temperature and annealing time using UV exposure. Besides, the reliability of silicon direct bonding with UV exposure enhancement after the high/low temperature cycle test, constant temperature and humidity test, vibration test and shock test is investigated. It follows from the results that the bonding strength of silicon wafer pairs with UV exposure decreases after the environmental tests, whereas the residual strength is still higher than that without UV exposure, and the variation trends of bonding strength vs. UV exposure time, annealing temperature and annealing time remain unchanged. Therefore, following the traditional wet chemical activation processes, appropriate UV exposure (about three minutes in this study) is effective and promising to enhance silicon direct bonding.

关键词： ultraviolet (UV) exposure     silicon direct bonding     bonding strength     reliability    

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大空间内着火位置对火灾增长的影响

石龙,张瑞芳, 谢启源,付丽华

《中国工程科学》 2008年 第10卷 第11期   页码 37-42

摘要：

以大空间展厅为例，利用火源辐射模型和烟气辐射模型并结合CFAST6.0区域模拟软件的计算结果，对比分析了大空间内不同着火位置下火灾增长的情况。研究结果表明仅考虑火源热辐射的情况下，展厅内着火位置越处于左右中间对称处，其火灾增长越快，热释放速率峰值也越大，达到热释放速率峰值的时间和火灾的持续时间越短，处于展厅中心位置时所有值达峰值。对火源热辐射和烟气辐射综合考虑时，到达热释放速率峰值时间与火灾持续时间的规律同仅考虑火源辐射模型时一致，但热释放速率峰值均有不同程度的提高。

关键词： 火灾增长     大空间着火位置     火灾场景设置     火源辐射模型     烟气辐射模型    

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从中国首台紫外-可见光高光谱卫星仪器反演得到的高空间分辨率臭氧廓线 Article

Fei Zhao, Cheng Liu, Qihou Hu, Congzi Xia, Chengxin Zhang, Wenjing Su

《工程（英文）》 2024年 第32卷 第1期   页码 107-116 doi: 10.1016/j.eng.2023.02.020

摘要：

Understanding the vertical distribution of ozone is crucial when assessing both its horizontal and vertical transport, as well as when analyzing the physical and chemical properties of the atmosphere. One of the most effective ways to obtain high spatial resolution ozone profiles is through satellite observations. The Environmental Trace Gases Monitoring Instrument (EMI) deployed on the Gaofen-5 satellite is the first Chinese ultraviolet-visible hyperspectral spectrometer. However, retrieving ozone profiles using backscattered radiance values measured by the EMI is challenging due to unavailable measurement errors and a low signal-to-noise ratio. The algorithm developed for the Tropospheric Monitoring Instrument did not allow us to retrieve 87% of the EMI pixels. Therefore, we developed an algorithm specific to the characteristics of the EMI. The fitting residuals are smaller than 0.3% in most regions. The retrieved ozone profiles were in good agreement with ozonesonde data, with maximum mean biases of 20% at five latitude bands. By applying EMI averaging kernels to the ozonesonde profiles, the integrated stratospheric column ozone and tropospheric column ozone also showed excellent agreement with ozonesonde data. The lower layers (0–7.5 km) of the EMI ozone profiles reflected the seasonal variation in surface ozone derived from the China National Environmental Monitoring Center (CNEMC). However, the upper layers (9.7–16.7 km) of the ozone profiles show different trends, with the ozone peak occurring at an altitude of 9.7–16.7 km in March. A stratospheric intrusion event in central China from August 11 to 15, 2019, is captured using the EMI ozone profiles, potential vorticity data, and relative humidity data. The increase in the CNEMC ozone concentration showed that downward transport enhanced surface ozone pollution.

关键词： Ozone profiles     EMI     Soft calibration     Floor noise correction     Stratospheric ozone intrusion    

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All-inorganic TiO/CsAgBiBr composite as highly efficient photocatalyst under visible light irradiation

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 1925-1936 doi: 10.1007/s11705-023-2344-6

摘要： In recent years, limited photocatalysis efficiency and wide band gap have hindered the application of TiO2 in the field of photocatalysis. A leading star in photocatalysis has been revealed as lead-free Cs2AgBiBr6 double halide perovskite nanocrystals, owing to its strong visible light absorption and tunable band gap. In this work, this photocatalytic process was facilitated by a unique TiO2/Cs2AgBiBr6 composite, which was identified as an S-cheme heterojunction. TiO2/Cs2AgBiBr6 composite was investigated for its structure and photocatalytic behavior. The results showed that when the perovskite dosage is 40%, the photocatalytic rate of TiO2 could be boosted to 0.1369 min–1. This paper discusses and proposes the band gap matching, carrier separation, and photocatalytic mechanism of TiO2/Cs2AgBiBr6 composites, which will facilitate the generation of new ideas for improving TiO2’s photocatalytic performance.

关键词： Cs2AgBiBr6 nanocrystals     visible-light photocatalyst     Cs2AgBiBr6/TiO2 heterojunction    

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通过DOM的光谱特性对长江源头典型高原深水湖泊进行评价

田林锋,胡继伟,李存雄,黄先飞,谢伟芳

《中国工程科学》 2010年 第12卷 第6期   页码 80-84

摘要：

天然溶解有机质（dissolved organic matter, DOM）研究在水体生态环境系统的修复研究中扮演着重要的角色，是近年来水环境研究领域的一个热点和难点。目前，紫外―可见光谱和分子荧光光谱在天然溶解有机质是表征天然溶解有机质的重要有效的手段，也是研究天然溶解有机质的主要手段。红枫湖为贵阳市5 个主要饮用水源地之一，对贵阳市社会发展具有重要作用。采用紫外―可见光谱和分子荧光光谱相结合的研究方法，对采自红枫湖中10个点的水样中天然溶解有机质的光谱特性研究。研究结果表明，红枫湖水体光谱特征主要表现为紫外―可见吸光值参数 E3/E4的变化范围是1.70~8.77。除后五火电厂外，水下10 m比水下5 m的 E3/E4 值要高。此外，荧光指数 f 450/500 的变化范围是1.38~1.52。初步认为红枫湖目前的主要有机物污染是陆源性的。后五火电厂，北湖湖心和张官三点水样的光谱特征与其他地方不同。同时还表明溶解有机质的腐殖化程度与水深具有一定的相关性。

关键词： 天然溶解有机质     紫外―可见光谱     分子荧光光谱     相关性    

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Correlations for estimating solar radiation using sunshine hours and temperature measurement in Osogbo

O. S. OHUNAKIN, M. S. ADARAMOLA, O. M. OYEWOLA, R. O. FAGBENLE

《能源前沿（英文）》 2013年 第7卷 第2期   页码 214-222 doi: 10.1007/s11708-013-0241-2

摘要： In this study, the global solar radiation on horizontal surface in Osogbo, Osun state, Nigeria was analyzed using 11-year data (1997–2007). Correlations using linear and quadratic expressions were developed to relate the global solar radiation on horizontal surface based on relative sunshine hours and temperature measurements for evaluating the monthly average daily global solar radiation. The calculated monthly clearness index values indicate that the prevailing weather condition in Osogbo is heavily overcast. All the developed quadratic correlations gave better correlation coefficients (0.834, 0.872 and 0.823 respectively) than the linear models. However, the Hargreaves and Samani related based quadratic model gave the best among the three developed quadratic expressions and is therefore suggested for estimating the monthly global radiation in this site and its surroundings.

关键词： global solar radiation     Hargreaves model     sunshine hour     ambient temperatures     Osogbo    

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标题 作者 时间 类型 操作

Ambient photolysis frequency of NO

Qi Zou,Keding Lu,Yusheng Wu,Yudong Yang,Zhuofei Du,Min Hu

期刊论文

Theoretical study on flow and radiation in tubular solar photocatalytic reactor

期刊论文

Photodegradation of chromophoric dissolved organic matters in the water of Lake Dianchi, China

Yuan ZHANG,Chunming HU,Tao YU

期刊论文

Preparation and characterization of polyimide/silica/silver composite films

JIANG Lizhong, WU Dezhen, LUO Ning, WU Zhanpeng, MOU Nanxiang

期刊论文

Is atmospheric oxidation capacity better in indicating tropospheric O formation?

期刊论文

Review on the applications of Tropospheric Emissions Spectrometer to air-quality research: Perspectives

Yuxuan WANG, Yuqiang ZHANG, Jiming HAO,

期刊论文

A method of determining flame radiation fraction induced by interaction burning of tri-symmetric propanefires in open space based on weighted multi-point source model

Jie JI, Junrui DUAN, Huaxian WAN

期刊论文

Nongray radiation from gas and soot mixtures in planar plates based on statistical narrow-band spectralmodel

Huaqiang CHU, Qiang CHENG, Huaichun ZHOU, Fengshan LIU

期刊论文

Smart model for accurate estimation of solar radiation

Lazhar ACHOUR, Malek BOUHARKAT, Ouarda ASSAS, Omar BEHAR

期刊论文

Ultraviolet exposure enhanced silicon direct bonding

Guanglan LIAO, Xuekun ZHANG, Xiaohui LIN, Canghai MA, Lei NIE, Tielin SHI,

期刊论文

大空间内着火位置对火灾增长的影响

石龙,张瑞芳, 谢启源,付丽华

期刊论文

从中国首台紫外-可见光高光谱卫星仪器反演得到的高空间分辨率臭氧廓线

Fei Zhao, Cheng Liu, Qihou Hu, Congzi Xia, Chengxin Zhang, Wenjing Su

期刊论文

All-inorganic TiO/CsAgBiBr composite as highly efficient photocatalyst under visible light irradiation

期刊论文

通过DOM的光谱特性对长江源头典型高原深水湖泊进行评价

田林锋,胡继伟,李存雄,黄先飞,谢伟芳

期刊论文

Correlations for estimating solar radiation using sunshine hours and temperature measurement in Osogbo

O. S. OHUNAKIN, M. S. ADARAMOLA, O. M. OYEWOLA, R. O. FAGBENLE

期刊论文