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2021全球十大工程成就 2

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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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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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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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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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Patterned wafer bonding using ultraviolet adhesive

Rui ZHUO, Guanglan LIAO, Wenliang LIU, Lei NIE, Tielin SHI

《机械工程前沿（英文）》 2011年第6卷第2期页码 214-218 doi: 10.1007/s11465-011-0130-5

摘要：

The process of patterned wafer bonding using ultraviolet (UV) adhesive as the intermediate layer was studied. By presetting the UV adhesive guide-layer, controlling the thickness of the intermediate layer (1– 1.5 μm), appropriate pre-drying temperature (60°C), and predrying time (6 min), we obtained the intermediate layer bonding of patterned quartz/quartz. Experimental results indicate that patterned wafer bonding using UV adhesive is achieved under room temperature. The process also has advantages of easy operation, low cost, and no plugging or leakage in the patterned area after bonding. Using the process, a microfluidic chip for red blood cell counting was designed and fabricated. Patterned wafer bonding using UV adhesive will have great potential in the fabrication of microfluidic chips.

关键词： ultraviolet (UV) adhesive intermediate layer patterned wafer bonding

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Novel Ag-AgBr decorated composite membrane for dye rejection and photodegradation under visible light

Yixing Wang, Liheng Dai, Kai Qu, Lu Qin, Linzhou Zhuang, Hu Yang, Zhi Xu

《化学科学与工程前沿（英文）》 2021年第15卷第4期页码 892-901 doi: 10.1007/s11705-020-2011-0

摘要： Photocatalytic membranes have received increasing attention due to their excellent separation and photodegradation of organic contaminants in wastewater. Herein, we bound Ag-AgBr nanoparticles onto a synthesized polyacrylonitrile-ethanolamine (PAN-ETA) membrane with the aid of a chitosan (CS)-TiO layer via vacuum filtration and partial reduction. The introduction of the CS-TiO layer improved surface hydrophilicity and provided attachment sites for the Ag-AgBr nanoparticles. The PAN-ETA/CS-TiO /Ag-AgBr photocatalytic membranes showed a relatively high water permeation flux (~ 47 L·m ·h ·bar ) and dyes rejection (methyl orange: 88.22%; congo red: 95%; methyl blue: 97.41%; rose bengal: 99.98%). Additionally, the composite membranes exhibited potential long-term stability for dye/salt separation (dye rejection: ~97%; salt rejection: ~6.5%). Moreover, the methylene blue and rhodamine B solutions (20 mL, 10 mg·L ) were degraded approximately 90.75% and 96.81% in batch mode via the synthesized photocatalytic membranes under visible light irradiation for 30 min. This study provides a feasible method for the combination of polymeric membranes and inorganic catalytic materials.

关键词： Ag-AgBr dye rejection photodegradation visible light

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Low temperature synthesis of visible light responsive rutile TiO

John TELLAM, Xu ZONG, Lianzhou WANG

《化学科学与工程前沿（英文）》 2012年第6卷第1期页码 53-57 doi: 10.1007/s11705-011-1165-1

摘要： A nano-structured TiO with rutile phase was synthesized by using the hydrothermal method from a titanium carbide (TiC) nano-powder precursor at low temperature to produce a stable visible light responsive photocatalyst. The rutile phase was formed at temperature as low as 100°C, and both synthesis time and temperature affected its formation. The rutile particles showed a faceted nano-rod structure, and were tested for absorption and photo-degradation ability under visible light. Particles with shorter synthesis times showed higher visible light absorption and corresponding photo-degradation ability, while those synthesized at lower temperatures had lower, but still evident, degradation ability under visible light.

关键词： photocatalysis rutile TiO₂ hydrothermal visible titanium carbide

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Effects of design parameters on performance and cost analysis of combined ultraviolet-biofilter systems

Can WANG, Jinying XI, Hongying HU, Insun KANG

《环境科学与工程前沿（英文）》 2012年第6卷第4期页码 588-594 doi: 10.1007/s11783-012-0433-8

摘要： A conceptual mathematical model was used to evaluate the design parameters of a combined ultraviolet (UV)-biofilter system, and perform a cost analysis. Results showed that the UV light source strength and the gas residence times in the UV system (UVRT) and biofilter (EBRT) had positive effects on the overall chlorobenzene removal efficiency of the system. High ratio of UVRT to EBRT improved the removal efficiency, suggesting that the UV system has a greater effect on the overall performance of the system compared with the biofilter. Analysis of the capital and operating costs showed that the capital costs of the standalone biofilter system were much higher than those of the standalone UV system. However, the biofilter operating costs were lower than those of the UV system. The operating costs of the combined UV-biofilter system increased with increasing UVRT/EBRT ratio, whereas its capital costs decreased.

关键词： volatile organic compounds ultraviolet (UV) photodegradation biofilter modeling cost analysis

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Tuning nitrogen defects and doping sulfur in carbon nitride for enhanced visible light photocatalytic

《化学科学与工程前沿（英文）》 2023年第17卷第1期页码 93-101 doi: 10.1007/s11705-022-2175-x

摘要： Defect construction and heteroatom doping are effective strategies for improving photocatalytic activity of carbon nitride (g-C₃N₄). In this work, N defects were successfully prepared via cold plasma. High-energy electrons generated by plasma can produce N defects and embed sulfur atoms into g-C₃N₄. The N defects obviously promoted photocatalytic degradation performance that was 7.5 times higher than that of pure g-C₃N₄. The concentration of N defects can be tuned by different power and time of plasma. With the increase in N defects, the photocatalytic activity showed a volcanic trend. The g-C₃N₄ with moderate concentration of N defects exhibited the highest photocatalytic activity. S-doped g-C₃N₄ exhibited 11.25 times higher photocatalytic activity than pure g-C₃N₄. It provided extra active sites for photocatalytic reaction and improved stability of N defects. The N vacancy-enriched and S-doped g-C₃N₄ are beneficial for widening absorption edge and improving the separation efficiency of electron and holes.

关键词： g-C₃N₄ nitrogen defect sulfur doping photodegradation plasma

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Effect of ultraviolet irradiation and chlorination on ampicillin-resistant

Yuchen PANG,Jingjing HUANG,Jinying XI,Hongying HU,Yun ZHU

《环境科学与工程前沿（英文）》 2016年第10卷第3期页码 522-530 doi: 10.1007/s11783-015-0779-9

摘要： Antibiotic resistance is a serious public health risk that may spread via potable and reclaimed water. Effective disinfection is important for inactivation of antibiotic-resistant bacteria and disruption of antibiotic resistance genes. Ampicillin is a widely prescribed antibiotic but its effectiveness is increasingly undermined by resistance. In this study, changes in ampicillin resistance for ( ) CGMCC 1.1595 were analyzed after exposure to different doses of ultraviolet (UV) or chlorine, and damage incurred by the plasmid encoding ampicillin resistance gene was assessed. We reported a greater stability in ampicillin-resistant CGMCC 1.1595 after UV irradiation or chlorination when compared with previously published data for other strains. UV irradiation and chlorination led to a shift in the mortality frequency distributions of ampicillin-resistant when subsequently exposed to ampicillin. The ampicillin hemi-inhibitory concentration (IC ) without disinfection was 3800 mg·L , and an increment was observed after UV irradiation or chlorination. The IC of ampicillin-resistant was 1.5-fold higher at a UV dose of 40 mJ·cm , and was 1.4-fold higher when exposed to 2.0 mg·L chlorine. These results indicate that UV irradiation and chlorination can potentially increase the risk of selection for strains with high ampicillin resistance. There was no evident damage to after 1–10 mg Cl ·L chlorination, while a UV dose of 80 mJ·cm yielded a damage ratio for of approximately 1.2-log. Therefore, high UV doses are required for effective disruption of antibiotic resistance genes in bacteria.

关键词： antibiotic resistance Escherichia coli ampicillin resistance gene ultraviolet irradiation chlorination

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Toward better understanding vacuum ultraviolet–iodide induced photolysis via hydrogen peroxide formation

《环境科学与工程前沿（英文）》 2022年第16卷第5期 doi: 10.1007/s11783-021-1489-0

摘要：

• UV/VUV/I^– induces substantial H₂O₂ and IO₃^– formation, but UV/I^– does not.

关键词： Vacuum ultraviolet Hydrogen peroxide Iodate Hydroxyl radical Redox transition

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Visible-light-driven heterostructured g-CN/Bi-TiO floating photocatalyst with enhanced charge carrier

《环境科学与工程前沿（英文）》 2021年第15卷第6期 doi: 10.1007/s11783-021-1417-3

摘要：

• Bi doping in TiO₂ enhanced the separation of photo-generated electron-hole.

关键词： Bi doping Visible light Algal removal Charge carrier separation

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recyclable BiOBr/silk fibroin-cellulose acetate composite film for efficient photodegradation of dyes under visible

《化学科学与工程前沿（英文）》 2023年第17卷第11期页码 1765-1775 doi: 10.1007/s11705-023-2323-y

摘要： A stable and recyclable of BiOBr/silk fibroin-cellulose acetate composite film was prepared by blending-wet phase transformation and in situ precipitate technology. The cellulose acetate film modified by silk fibroin formed a finger-shaped porous structure, which provided a large space for the uniform growth of BiOBr nanosheets and facilitated the shuttle flow of dyes in film. The morphology, phase structure, and optical properties of the composite films were characterized using various techniques, and their photocatalytic performance for dye wastewater was evaluated under visible light irradiation. Results showed that the BiOBr/SF-CA composite film exhibited efficient photocatalytic activity with 99.9% of rhodamine B degradation rate. Moreover, the composite film maintained high catalytic stability because Bi as the active species deposited on the film showed almost no loss. Finally, the possible photocatalytic mechanisms in the BiOBr/SF-CA composite film were speculated through radical-trapping experiments and electron spin resonance testing.

关键词： BiOBr nanosheet cellulose acetate silk fibroin photocatalytic degradation dye wastewater