40 results on '"Yan, Hao"'
Search Results
2. Fine particulate matter (PM2.5/PM1.0) in Beijing, China: Variations and chemical compositions as well as sources
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Lining Luo, Xiaoxuan Bai, Shuhan Liu, Bobo Wu, Wei Liu, Yunqian Lv, Zhihui Guo, Shumin Lin, Shuang Zhao, Yan Hao, Jiming Hao, Kai Zhang, Aihua Zheng, and Hezhong Tian
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Environmental Engineering ,Environmental Chemistry ,General Medicine ,General Environmental Science - Published
- 2022
3. Heterogeneous Variations on Historical and Future Trends of CO2 and Multiple Air Pollutants from the Cement Production Process in China: Emission Inventory, Spatial–Temporal Characteristics, and Scenario Projections
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Zhihui Guo, Xiaoxuan Bai, Shuhan Liu, Lining Luo, Yan Hao, Yunqian Lv, Yifei Xiao, Junqi Yang, and Hezhong Tian
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Environmental Chemistry ,General Chemistry - Published
- 2022
4. Emissions of multiple metals from vehicular brake linings wear in China, 1980–2020
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Zhiqiang Fu, Yiming Wu, Shuang Zhao, Xiaoxuan Bai, Shuhan Liu, Hongyan Zhao, Yan Hao, and Hezhong Tian
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Environmental Engineering ,Environmental Chemistry ,Pollution ,Waste Management and Disposal - Published
- 2023
5. Study on the relationship between crystallization characteristics of quenched droplets and the effect of cell cryopreservation with Raman spectroscopy
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Taijie Zhan, Wenya Niu, Mengdong Cui, Hengxin Han, Hangyu Dang, Ning Guo, Ding Wang, Yan Hao, Chuanbao Zang, and Yi Xu
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Electrochemistry ,Environmental Chemistry ,Biochemistry ,Spectroscopy ,Analytical Chemistry - Abstract
The cryopreservation method of microdroplets has steadily become widely employed in the cryopreservation of microscale biological samples such as various types of cells due to its fast cooling rate, significant...
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- 2023
6. Applying synchronous fluorescence spectra with Gaussian band fitting and two-dimensional correlation to characterize structural composition of DOM from soils in an aquatic-terrestrial ecotone
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Dongping Liu, Yan Hao, Hongjie Gao, Huibin Yu, and Qingqian Li
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Soil ,Lakes ,China ,Environmental Engineering ,Spectrometry, Fluorescence ,Environmental Chemistry ,Humans ,Esters ,Dissolved Organic Matter ,Pollution ,Waste Management and Disposal ,Amides ,Humic Substances - Abstract
Dissolved organic matter (DOM), the primary participant of carbon and nitrogen cycle, has a great impact on the behavior and fate of organic pollutants and heavy metals in eutrophic lakes. The dynamic spectral properties of DOM fractions were revealed in an aquatic-terrestrial ecotone under the different types of land use. Composite soil samples of different depths (0-20, 20-40 and 40-60 cm) were collected from four different land uses along a disturbed-impact gradient in Taihu Lake, China, i.e., grassland (GRL), forest land (FOL), paddy field (PAF), and vegetable field (VEF). DOM mainly consisted of tyrosine-like material (TYLF), tryptophan-like material (TRLF), microbial humic-like material (MHLF), fulvic-like material (FLF) and humic-like material (HLF) within all soil profiles, where TRLF was the dominant component (61.30 %) using synchronous fluorescence spectroscopy (SFS) combined with principal component analysis and Gaussian band fitting. Based on two-dimensional correlation spectroscopy with SFS and Fourier transform infrared, the variation order of DOM fractions was FLF → MHLF → HLF → TRLF → TYLF within the GRL soil profile, and MHLF exhibited an oppositive change with aliphatic OH and amide I in protein. The order of DOM fractions was MHLF → FLF → HLF → TYLF → TRLF within the FOL soil profile, and the change trend of MHLF remained oppositive with aliphatic OH and CO in ester. The order of DOM within the PAF soil profile fractions was TRLF → MHLF → HLF → TYLF → FLF, and changing trends of TYLF were oppositive to aliphatic OH, CH bending vibration, CH bending vibration and CO in ester. The order of DOM fractions was HLF → TYLF → TRLF → FLF → MHLF within the VEF soil profile, where the changing trend TYLF remained oppositive to aliphatic OH, CH deformations in lignin and aliphatic group and amide I in protein. This study may provide important support for alleviating lake water eutrophication or pollution.
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- 2022
7. Radiation Syntheses and Performance of Novel Hierarchically Macro-/Mesoporous Silica Adsorbents with Quaternary Phosphonium for the High Selective Removal of Perrhenate
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Jiuqiang Li, Long Zhao, Shouchao Zhong, Xingxiao Li, Yue Wang, Maolin Zhai, Jing Peng, Yan Hao, and Dong Han
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chemistry.chemical_compound ,Perrhenate ,Adsorption ,Chemical engineering ,Renewable Energy, Sustainability and the Environment ,Chemistry ,General Chemical Engineering ,Environmental Chemistry ,General Chemistry ,Phosphonium ,Mesoporous silica - Published
- 2021
8. Current Status and Potential Assessment of China's Ocean Carbon Sinks
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Chang Liu, Gengyuan Liu, Marco Casazza, Ningyu Yan, Linyu Xu, Yan Hao, Pier Paolo Franzese, and Zhifeng Yang
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Carbon Sequestration ,China ,applied physics ,enhancing potential ,mariculture carbon sink ,Oceans and Seas ,environmental accounting ,resources flows ,General Chemistry ,Carbon ,environmental physics ,Carbon Cycle ,offshore carbon sink ,blue carbon ,ocean carbon sink ,Environmental Chemistry ,Ecosystem - Abstract
The role of ocean carbon sinks in global climate change mitigation and carbon neutrality is still affected by lack of research. Aiming at overcoming the present limitations, a comprehensive and holistic framework and accounting method of ocean carbon sink evaluation are proposed in this study, which consider both carbon sink types and their characteristic carbon storage cycle timescales. The results show that (1) China's total ocean carbon sink is 69.83-106.46 Tg C/year, among which the mariculture, coastal wetlands, and offshore carbon sinks are 2.27-4.06, 2.86-5.85, and 64.70-96.55 Tg C/year, respectively; (2) ocean-based solutions such as coastal protection and restoration, mariculture development, ocean alkalization, ocean fertilization, and marine bioenergy with carbon capture and storage have substantial mitigation potential, but further investigation is required before large-scale deployment; (3) although China's ocean carbon sinks only counterbalanced 3.27-4.99% of its fossil fuel emissions, their tremendous enhancing potential and specific advantages cannot be ignored, and enhancing measures must be taken according to regional characteristics; (4) some uncertainties and limitations still exist, and problems such as double counting, carbon sink offset, and so forth need to be further considered. In a word, this study provides a basis for the development of ocean-based solutions on closing climate mitigation gaps.
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- 2022
9. Exploring the driving factors of haze events in Beijing during Chinese New Year holidays in 2020 and 2021 under the influence of COVID-19 pandemic
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Lining, Luo, Xiaoxuan, Bai, Yunqian, Lv, Shuhan, Liu, Zhihui, Guo, Wei, Liu, Yan, Hao, Yujiao, Sun, Jiming, Hao, Kai, Zhang, Hongyan, Zhao, Shumin, Lin, Shuang, Zhao, Yifei, Xiao, Junqi, Yang, and Hezhong, Tian
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Environmental Engineering ,Environmental Chemistry ,Pollution ,Waste Management and Disposal - Abstract
Unexpected outbreak of the 2019 novel coronavirus (COVID-19) has profoundly altered the way of human life and production activity, which posed visible impacts on PM
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- 2023
10. Solvent-less Dehydrogenative C–H Etherification with Alcohols Using Mechanochemistry
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Qiu-Zi Wu, Zhen-Yuan Xu, Yang-Jie Mao, Hong-Yan Hao, Kun Zhou, Jin Wu, Lei Chen, Shuang Wang, Dan-Qian Xu, and Shao-Jie Lou
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Renewable Energy, Sustainability and the Environment ,Chemistry ,General Chemical Engineering ,Aryl ,Late stage ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Solvent ,chemistry.chemical_compound ,Reagent ,Mechanochemistry ,Environmental Chemistry ,Organic chemistry ,0210 nano-technology ,Ball mill - Abstract
The aromatic C–H bond etherification with alcohols is one of the most atom-efficient ways to construct aryl ethers. However, it often requires a large excess of alcohols as etherification reagents,...
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- 2021
11. Subannual-to-biannual-resolved travertine record of Asian Summer Monsoon dynamics in the early Holocene at the eastern margin of Tibetan Plateau
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Sun, Hailong, Shen, Chuan-Chou, Wu, Chung-Che, Chen, Bo, Yin, Jianjun, Yan, Hao, Dong, Jinguo, An, Dejun, Tang, Shu, and Zhang, Qingming
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Geochemistry and Petrology ,Environmental Chemistry ,Pollution - Abstract
In this study, we present a subannual–biannual-resolved (0.9–2 years) ASM intensity record spanning from 11.6 to 10.0 ka BP (before 1950 AD) inferred from a 230Th-dated travertine δ18O record at Zhangjia Ravine on the eastern margin of the Tibetan Plateau. The ZJG-1 δ18O sequence is characterized by high-frequency fluctuations at decadal to centennial scales. Fluctuating between - 11.15‰ and - 14.78‰ over the δ18O sequence, the fluctuation range gradually decreased from 11.6 to 10.0 ka BP. There are several abrupt changes in the δ18O sequence, which indicate that the ASM in the early Holocene was highly unstable. Comparison with marine records suggests that the Preboreal oscillation (PBO) event could be triggered by a freshwater outburst which led to/resulted in a sudden release of thousands of cubic kilometers of the meltwater to the North Atlantic Ocean. Furthermore, the climate oscillations during the PBO were associated with the complex interplay of solar activity and freshwater outburst, the freshwater outburst may amplify the effect of solar activity when it was in the minima. The rapid warming after the PBO event may be controlled by the common mechanism that induced the Dansgaard–Oeschger warming events during the last glacial period. The further pronounced increases of the travertine δ18O values occurred at about 10.3 ka BP, coinciding roughly with Bond 7 event, also caused by the freshwater outburst and solar activity. This study is not only important to understand the primary driving force of the ASM intensity in the early Holocene, but also essential for evaluate the probability of abrupt climate changes in the future.  
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- 2022
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12. Hydrochemical characteristics in karst reservoirs and its implication for inorganic carbon deposition fluxes
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Liu Zaihua, Yan Hao, Sun Hai-long, Bao Qian, Wei Yu, Han Cuihong, and Ma Song
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geography ,geography.geographical_feature_category ,Total inorganic carbon ,Environmental chemistry ,Earth and Planetary Sciences (miscellaneous) ,Environmental science ,Aquatic Science ,Karst ,Pollution ,Deposition (chemistry) ,Water Science and Technology - Published
- 2021
13. MiR-122 is involved in immune response by regulating Interleukin-15 in the orange-spotted grouper (Epinephelus coioides)
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Nina Wei, QingJian Liang, Xing Liu, Yan Hao, YinHua Liu, and LiPing Peng
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Fish Proteins ,0301 basic medicine ,Orange-spotted grouper ,Spleen ,Aquatic Science ,Biology ,Microbiology ,Fish Diseases ,03 medical and health sciences ,Immune system ,medicine ,Animals ,Environmental Chemistry ,Grouper ,Phylogeny ,Interleukin-15 ,Base Sequence ,Cell growth ,Gene Expression Profiling ,04 agricultural and veterinary sciences ,General Medicine ,Epinephelus ,biology.organism_classification ,Immunity, Innate ,Aeromonas hydrophila ,MicroRNAs ,030104 developmental biology ,medicine.anatomical_structure ,Gene Expression Regulation ,Interleukin 15 ,040102 fisheries ,0401 agriculture, forestry, and fisheries ,Bass ,Gram-Negative Bacterial Infections ,Sequence Alignment - Abstract
Epinephelus coioides is an important economic culture marine fish and is susceptible to various pathogenic diseases. Increasingly evidences showed that miRNAs participated in the regulation of the cell proliferation, differentiation and immune response. MiR-122 has been reported to play an essential role in immune response by triggering an inflammatory reaction. However, the function of miR-122 in response to bacterial infection is unclear in Epinephelus coioides. Herein, we report that miR-122 is involved in response to Aeromonas hydrophila infection of grouper spleen cells (GS). IL-15, IL-6 and IL-1β are inhibited in overexpression miR-122 GS cells, while induced in silence miR-122 GS cells. In addition, IL-15 is predicted to be the target gene of miR-122, which is further confirmed by LUC. Taken together, we propose that miR-122 regulates the immune response to bacterial infection by triggering IL-15.
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- 2020
14. A comprehensive emission inventory of hazardous air pollutants from municipal solid waste incineration in China
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Zhiqiang Fu, Shumin Lin, Hezhong Tian, Yan Hao, Bobo Wu, Shuhan Liu, Lining Luo, Xiaoxuan Bai, Zhihui Guo, and Yunqian Lv
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Air Pollutants ,China ,Environmental Engineering ,Environmental Chemistry ,Incineration ,Dibenzofurans, Polychlorinated ,Solid Waste ,Pollution ,Waste Management and Disposal - Abstract
The Hazardous air pollutants (HAPs) released from increasing municipal solid waste incineration (MSWI) plants have drawn great concerns in China. However, a full picture of their emission characteristics is still urgently needed, especially after the implementation of stricter emission limits on MSWI. In this study, a comprehensive historical emission inventory of HAPs emitted from MSWI plants in China during the period of 2006-2017 was dedicatedly established by integrating with detailed plant-level activity data and renewed localized emission factors. Overall, HAPs emissions initially increased with years, then peaked or slowed increase in the year 2014, but leveled off after 2016 due to the gradually and fully implementing of newly revised national emission standard (GB18485-2014) applied to mainland China and much stricter local standards for several provinces and cities. It was estimated that totally 50,716 tons (t) of NOx, 13,026 t of CO, 7988 t of SO
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- 2022
15. Non-Negligible Stack Emissions of Noncriteria Air Pollutants from Coal-Fired Power Plants in China: Condensable Particulate Matter and Sulfur Trioxide
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Chuanyong Zhu, Lei Duan, Hezhong Tian, Yan Hao, Yunqian Lv, Xiaoxuan Bai, Yang Liu, Shumin Lin, Zhihui Guo, Lining Luo, Bobo Wu, Jiming Hao, Shuhan Liu, Wei Liu, and Shuang Zhao
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China ,Sulfur Oxides ,Air pollution ,010501 environmental sciences ,medicine.disease_cause ,01 natural sciences ,chemistry.chemical_compound ,Stack (abstract data type) ,Air Pollution ,medicine ,Environmental Chemistry ,Coal ,Sulfate ,Sulfur dioxide ,0105 earth and related environmental sciences ,Air Pollutants ,business.industry ,General Chemistry ,Particulates ,Flue-gas desulfurization ,chemistry ,Environmental chemistry ,Sulfur trioxide ,Environmental science ,Particulate Matter ,business ,Power Plants - Abstract
In this study, we investigated the emission characteristics of condensable particulate matter (CPM) and sulfur trioxide (SO3) simultaneously through ammonia-based/limestone-based wet flue gas desulfurization (WFGD) from four typical coal-fired power plants (CFPPs) by conducting field measurements. Stack emissions of filterable particulate matter (FPM) all meet the Chinese ultralow emission (ULE) standards, whereas CPM concentrations are prominent (even exceed 10 mg/Nm3 from two CFPPs). We find that NH4+ and Cl- increase markedly through the ammonia-based WFGD, and SO42- is generally the main ionic component, both in CPM and FPM. Notably, the occurrence of elemental Se in FPM and CPM is significantly affected by WFGD. Furthermore, the established chemical profiles in FPM and CPM show a distinct discrepancy. In CPM, the elemental S mainly exists as a sulfate, and the metallic elements of Na, K, Mg, and Ca mainly exist as ionic species. Our results may indicate that not all SO3 are included in CPM and they co-exist in stack plume. With the substantial reduction of sulfur dioxide (SO2), S distributed in SO3, CPM, and FPM becomes non-negligible. Finally, the emission factors of CPM and SO3 under typical ULE technical routes fall in the ranges of 74.33-167.83 and 48.76-86.30 g/(t of coal) accordingly.
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- 2020
16. Uptake kinetics of nitrogen and phosphorus by Zostera marina
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Pei-Dong Zhang, Zheng Li, Yan-Hao Zhang, and Shi-Qi Li
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Ecology ,biology ,Phosphorus ,chemistry.chemical_element ,Uptake kinetics ,Plant Science ,biology.organism_classification ,Nitrogen ,Michaelis–Menten kinetics ,Absorption rate ,chemistry ,Environmental chemistry ,Zostera marina ,Ecology, Evolution, Behavior and Systematics - Published
- 2020
17. Field measurements on emission characteristics, chemical profiles, and emission factors of size-segregated PM from cement plants in China
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Lining Luo, Yunqian Lv, Shuhan Liu, Yan Hao, Zhihui Guo, Xiaoxuan Bai, Shumin Lin, Bobo Wu, Yifei Xiao, Junqi Yang, Wei Liu, Hezhong Tian, and Shuang Zhao
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Cement ,Air Pollutants ,China ,Environmental Engineering ,business.industry ,Kiln ,Air pollution ,Particulates ,medicine.disease_cause ,Clinker (cement) ,Pollution ,Environmental chemistry ,Air Pollution ,medicine ,Environmental Chemistry ,Environmental science ,Coal ,Particulate Matter ,Emission inventory ,Particle Size ,business ,Waste Management and Disposal ,Air quality index ,Environmental Monitoring - Abstract
Cement manufacturing is a major contributor to ambient particulate matter (PM) pollution in China, threatening urban and regional air quality improvement. Here, we tested the typical outlets (kiln tail, kiln head, and coal mill) in one shaft kiln and three rotary kilns to investigate the mass concentrations, size distributions, and chemical compositions of size-segregated PM. Results show that the concentrations of PM in most samples are lower than the strict local emission standards (10 mg/Nm3). We show that the characteristic chemical compositions in PM for most tested outlets are Ca and Ca2+, while for shaft kiln are K, S, K+, and SO42-, and organic carbon. Elemental carbon accounts for a relatively high proportion of PM emitted from coal mills. Meanwhile, unstable and abnormal operating conditions and variations on feed coal compositions will cause high levels of NH4+ and Cl- in PM from the kiln tail/head. Besides, the emission factors (EFs) of PM2.5, PM10, and PM after air pollution control devices for typical outlets of cement plants are calculated, which fall in ranges of 0.16-2.48, 1.49-18.46, and 3.32-35.35 g/(t of clinker), respectively. It suggests that mass emission characteristics, source profiles, and EFs of PM have changed notably as emission standards become more stringent. We believe the newly detailed size-segregated PM EFs and chemical profiles will help update and compile the refined emission inventory for current cement production in China.
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- 2021
18. Atmospheric Vanadium Emission Inventory from Both Anthropogenic and Natural Sources in China
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Yan Hao, Shuhan Liu, Yunqian Lv, Shumin Lin, Zhihui Guo, Xiaoxuan Bai, Hezhong Tian, Shuang Zhao, Chuanyong Zhu, and Lining Luo
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Air Pollutants ,Urban agglomeration ,business.industry ,Air pollution ,Vanadium ,chemistry.chemical_element ,General Chemistry ,medicine.disease_cause ,Combustion ,Natural (archaeology) ,Lead (geology) ,Coal ,chemistry ,Environmental protection ,medicine ,Environmental Chemistry ,Environmental science ,Industry ,Emission inventory ,business ,Environmental Monitoring - Abstract
Vanadium is a strategically important metal in the world, although sustained exposure under high vanadium levels may lead to notable adverse impact on health. Here, we leverage a bottom-up approach to quantitatively evaluate vanadium emissions from both anthropogenic and natural sources during 1949-2017 in China for the first time. The results show that vanadium emissions increased by 86% from 1949 to 2005 to a historical peak value and then gradually decreased to 12.9 kt in 2017. With the effective implementation of air pollution control measures, vanadium emissions from anthropogenic sources decreased sharply after 2011. During 2011-2017, about half of vanadium emissions came from coal and oil combustion. In addition, industrial processes and natural sources also cannot be ignored, with the total contributions of more than 24%. The high levels of vanadium emissions were mainly distributed throughout the North China Plain and the eastern and coastal regions, especially in several urban agglomerations. Furthermore, the comprehensive evaluation by incorporating contrastive analysis, Monte Carlo approach, and GEOS-Chem simulation shows that vanadium emissions estimated in this study were reasonable and acceptable. The findings of our study provide not only a scientific foundation for investigating the health effects of vanadium but also useful information for formulating mitigation strategies.
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- 2021
19. Spatiotemporal Variations of Ambient Concentrations of Trace Elements in a Highly Polluted Region of China
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Wei Liu, Huanjia Liu, Yuxuan Wang, Bobo Wu, Xiangyang Liu, Shuhan Liu, Chuanyong Zhu, Shumin Lin, Yan Hao, Kai Zhang, Xiaoxuan Bai, Hezhong Tian, Yiming Wu, and Panyang Shao
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Trace (semiology) ,Atmospheric Science ,Geophysics ,Space and Planetary Science ,Environmental chemistry ,Earth and Planetary Sciences (miscellaneous) ,Environmental science - Published
- 2019
20. Smart construction of 3D N-doped graphene honeycombs with (NH4)2SO4 as a multifunctional template for Li-ion battery anode: 'A choice that serves three purposes'
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Hao Yang, Lingpu Jia, Kaipeng Wu, Yan Hao, Yue Pan, Kuibao Zhang, Ke Du, and Guorong Hu
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Fabrication ,Materials science ,010405 organic chemistry ,Graphene ,Doping ,Nanotechnology ,010402 general chemistry ,01 natural sciences ,Pollution ,0104 chemical sciences ,law.invention ,Ion ,Anode ,law ,Environmental Chemistry ,Electronics ,Doped graphene ,Nitrogen source - Abstract
Not only do theoretical studies predict that doping graphene with nitrogen can tailor its electronic properties and chemical reactivity but practical results have also shown that tuning the shapes of graphene could make it more applicable in electronic devices. However, the successful transfer of lab procedures to commercialization and scale-up fabrication of N-doped graphene with specific architectures still faces great challenges at the moment. Herein, we report a smart approach to rationally design and deliberately construct 3D N-doped honeycomb-structured graphene, denoted as 3D-NHrGO, by a (NH4)2SO4-templated self-assembly method in which (NH4)2SO4 plays the role of “a choice that serves three purposes”. (NH4)2SO4 can not only facilitate the ultrafast separation of GO from the obtained mixed liquor of Hummers’ method, but also act as a nitrogen source and a green template to tailor the electronic properties as well as control the morphology of 3D-NHrGO, respectively. Particularly, (NH4)2SO4 can be recovered with simple recrystallization at the end of the synthesis, which makes the process environment-friendly and resource-effective. The compositions, structures, and morphologies of the samples during overall evolution of the synthetic procedure were investigated, and the substitution of N in the graphene framework is also evidenced. When evaluated as an anode material for Li-ion battery, the 3D-NHrGO gives high rate capability and stable cycle life. This research inspires new methodologies in addressing the enormous problems associated with the traditional graphene preparation process while using GO as the precursor, and sheds light on the great potential of industrially viable manufacturing of 3D N-doped graphene architectures for other applications.
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- 2019
21. Study of carbon metabolic processes and their spatial distribution in the Beijing-Tianjin-Hebei urban agglomeration
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Zhifeng Yang, Zhongming Lu, Qiong Wu, Yan Hao, Yan Zhang, Xinyue Zhao, and Ruimin Liu
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Environmental Engineering ,010504 meteorology & atmospheric sciences ,Land use ,Urban agglomeration ,Economies of agglomeration ,Environmental engineering ,chemistry.chemical_element ,010501 environmental sciences ,Spatial distribution ,01 natural sciences ,Pollution ,chemistry ,Transfer (computing) ,Spatial ecology ,Environmental Chemistry ,Environmental science ,Absorption (electromagnetic radiation) ,Waste Management and Disposal ,Carbon ,0105 earth and related environmental sciences - Abstract
It is necessary to reduce carbon emission, and land-use adjustment is one of the potential strategies. In this paper, we calculated the carbon emission and absorption rates in China's Beijing-Tianjin-Hebei agglomeration. We used ArcGIS to simulate their spatial patterns based on land-transfer matrices (land-use transitions) at 5-year intervals. From 2000 to 2015, carbon emission first increased and then decreased, but carbon absorption increased steadily. Transportation and industrial land accounted for 73.0% of carbon emission, whereas forest accounted for 55.0% of carbon absorption. The spatial distributions of emission and absorption evolved, developing obvious spatial gradients. Land transfers leading to increased emission or decreased absorption (negative transfers) increased by 115.1% from 2000 to 2015; the corresponding area of land transferred first decreased and then increased. The area of land transferred increased more slowly than negative carbon transfers, mainly due to transfers to transportation and industrial land, which accounted for 90.0% of the total; the land transfers leading to reduced emissions or increased absorption (positive carbon transfers) and the amount of carbon transferred decreased or increased simultaneously. The area of land transferred increased more than positive carbon transfers. The positive carbon transfers increased slightly at the start of the study, but showed no significant overall change, mainly due to transfers from transportation and industrial land to urban land. However, positive carbon transfers from 2010 to 2015 increased to 21 times the starting value, mainly due to transfers from transportation and industrial land (92% of the total). Our analysis revealed unfavorable transfer directions and sizes and their spatial distribution, thereby providing a scientific basis for regional planning to reduce carbon emission through adjustment of the land use pattern.
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- 2018
22. Effects of Wet Flue Gas Desulfurization and Wet Electrostatic Precipitators on Emission Characteristics of Particulate Matter and Its Ionic Compositions from Four 300 MW Level Ultralow Coal-Fired Power Plants
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Shuhan Liu, Xiaoxuan Bai, Yiming Wu, Chuanyong Zhu, Yan Hao, Shumin Lin, Huanjia Liu, Wei Liu, Hezhong Tian, Weizhao Liang, Bobo Wu, Xiangyang Liu, and Panyang Shao
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Ions ,Air Pollutants ,010504 meteorology & atmospheric sciences ,Waste management ,Ionic bonding ,General Chemistry ,010501 environmental sciences ,Particulates ,Coal fired ,01 natural sciences ,Flue-gas desulfurization ,Coal ,Downstream (manufacturing) ,Environmental Chemistry ,Environmental science ,Particulate Matter ,Power Plants ,0105 earth and related environmental sciences - Abstract
To achieve ultralow-emission (ULE) standards, wet electrostatic precipitators (WESP) installed downstream from wet flue gas desulfurization (WFGD) have been widely used in Chinese coal-fired power plants (CFPPs). We conducted a comprehensive field test study at four 300 MW level ULE CFPPs, to explore the impact of wet clean processing (WFGD and WESP) on emission characteristics of three size fractions of particulate matter (PM: PM
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- 2018
23. Atmospheric emission inventory of hazardous air pollutants from biomass direct-fired power plants in China: Historical trends, spatial variation characteristics, and future perspectives
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Zhihui Guo, Bobo Wu, Shuhan Liu, Yan Hao, Shuang Zhao, Hezhong Tian, Xiaoxuan Bai, Yunqian Lv, Wei Liu, Lining Luo, Jiming Hao, and Shumin Lin
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Environmental Engineering ,010504 meteorology & atmospheric sciences ,business.industry ,Emission standard ,Biomass ,010501 environmental sciences ,Energy transition ,01 natural sciences ,Pollution ,Electricity generation ,Agriculture ,Environmental protection ,Environmental Chemistry ,Environmental science ,Scenario analysis ,Emission inventory ,business ,Waste Management and Disposal ,NOx ,0105 earth and related environmental sciences - Abstract
The agricultural and forestry biomass direct-fired power generation represents an important technology to promote the low-carbon energy transition and agricultural waste reuse in China. In recent years, emissions of hazardous air pollutants (HAPs) caused by the rapid biomass industrialization have attracted increasing attention. To investigate the characteristics of HAPs emitted from biomass power plants in China, a multiple-year comprehensive emission inventory including NOx, SO2, PM, PM10, PM2.5, and trace elements (As, Cd, Cr, Cu, Hg, Pb, Zn) has been established for the period of 2006–2017. As a result of the emission standard (GB13223-2011), emissions of conventional HAPs have declined since 2014. The results show that national total emissions in 2017 were estimated at 29,516.0 t of NOx, 14,192.1 t of SO2, 4100.7 t of PM, 2353.9 t of PM10, 1630.6 t of PM2.5, 3057.2 kg of As, 1622.8 kg of Cd, 8285.8 kg of Cr, 54,443.4 kg of Cu, 132.9 kg of Hg, 66,325.8 kg of Pb, and 175,587.9 kg of Zn, respectively. The majority of HAPs emissions have been concentrated in eastern, northeastern, and central areas of mainland China. Shandong, Heilongjiang, and Anhui represent the top three provinces with the highest HAPs emissions from 2012 to 2017. Besides, the future emissions in 2025 and 2035 under the ultra-low emission policy are predicted with scenario analysis.
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- 2020
24. Simulation study on the phase holdup characteristics of the gas–liquid-solid mini-fluidized beds with bubbling flow
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Xiangnan Li, Yan Hao, Shili Song, Peng Zhao, and Mengfan Fan
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Materials science ,Steady state ,General Chemical Engineering ,Bubble ,General Chemistry ,Mechanics ,Industrial and Manufacturing Engineering ,Discrete element method ,Physics::Fluid Dynamics ,Fluidized bed ,Phase (matter) ,Volume of fluid method ,Environmental Chemistry ,Fluidization ,Suspension (vehicle) - Abstract
Previous simulations of three-phase fluidization systems based on the Euler-Lagrange approach have made progress in the studies of bubble and suspension dynamics. However, for guiding the operation and design of reactors, it is obviously more practical to obtain the phase holdup characteristics under the steady state. In this study, the hydrodynamic simulations on the gas–liquid-solid mini-fluidized beds (GLS-mFBs) were performed from the initial introduction of bubbling flow to the steady three-phase fluidization using the coupling model of volume of fluid (VOF) and discrete element method (DEM). After the initial process of bubbling flow accompanied by redistribution of phase holdups, i.e., the contraction of fluidized bed, the steady state of the GLS-mFB was achieved and maintained by the interactions between bubbles and fluidized bed. The axial and radial profiles of phase holdups in the steady GLS-mFBs, which is difficult to measure through experiments, are obtained and discussed. It is found that the suspension resistance against the rising bubbles is strengthened by the wall confining effect arising from the shrinkage of bubble-wall gap under smaller column diameter, and the phase holdup characteristics and bubble dynamics are investigated and explained by this effect. The bubble wake, which plays an important role in the momentum exchange between bubbles and suspension, is analyzed in terms of formation mechanism and size changes. It is proved that the VOF-DEM simulation is an effective method to predict the phase holdups of the GLS-mFBs and explain the underlying hydrodynamic mechanism.
- Published
- 2022
25. Migration and Emission Characteristics of Ammonia/Ammonium through Flue Gas Cleaning Devices in Coal-Fired Power Plants of China
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Jiming Hao, Shumin Lin, Hezhong Tian, Xiaoxuan Bai, Yan Hao, Shuhan Liu, Lining Luo, Xiangyang Liu, Huanjia Liu, Shuang Zhao, Wei Liu, Weizhao Liang, Bobo Wu, and Chuanyong Zhu
- Subjects
Flue gas ,Air Pollutants ,China ,Waste management ,Air pollution ,General Chemistry ,010501 environmental sciences ,Coal fired ,medicine.disease_cause ,01 natural sciences ,Power (physics) ,Coal ,Ammonia ,Air Pollution ,Ammonium Compounds ,medicine ,Environmental Chemistry ,Retrofitting ,Environmental science ,Ammonia ammonium ,0105 earth and related environmental sciences ,Power Plants - Abstract
To investigate the up-to-date migration and emission characteristics of NH3/NH4+ in coal-fired power plants (CFPPs) after implementing ultralow emission retrofitting, typical air pollution control ...
- Published
- 2019
26. Variation characteristics of final size-segregated PM emissions from ultralow emission coal-fired power plants in China
- Author
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Bobo Wu, Yan Hao, Shuang Zhao, Shumin Lin, Shuhan Liu, Hezhong Tian, Jiming Hao, Xiangyang Liu, Wei Liu, Xiaoxuan Bai, Lining Luo, and Chuanyong Zhu
- Subjects
China ,010504 meteorology & atmospheric sciences ,Health, Toxicology and Mutagenesis ,Electrostatic precipitator ,Field tests ,010501 environmental sciences ,Coal fired ,Toxicology ,01 natural sciences ,chemistry.chemical_compound ,Size fractions ,Sulfate ,Particle Size ,0105 earth and related environmental sciences ,Air Pollutants ,Large particle ,General Medicine ,Particulates ,Pollution ,Flue-gas desulfurization ,Coal ,chemistry ,Environmental chemistry ,Environmental science ,Particulate Matter ,Environmental Monitoring ,Power Plants - Abstract
The ultralow emission (ULE) retrofits for Chinese coal-fired power plants (CFPPs) are nearing completion. Large-scale and rapid retrofits have resulted in significant changes in the emission level and characteristics of particulate matter (PM). To investigate the variation characteristics of final three size fractions PM (PM2.5, PM10−2.5, PM>10) emissions, we conducted field tests at the outlets of wet flue gas desulfurization (WFGD) and wet electrostatic precipitator (WESP) by a pair of two-stage virtual impactors in eight representative ULE CFPPs. Our results indicate that, after WESP installations, the mass concentrations of final PM are significantly reduced and those of the final total ions and elements decrease as most individual chemical compositions are reduced. WESP presents an excellent removal performance for large particle sizes and high PM concentrations. SO42− is the major ionic component at both the outlets of WFGD and WESP, and its proportion in total ions is reduced to some extent through WESP. Furthermore, the average mass contents of SO42− and most elements in PM2.5 are significantly lower than those in PM10−2.5 and PM>10 whether at the WFGD-outlets or WESP-outlets. By comparison, chemical profiles of PM have substantially changed after ULE retrofits, and those after WFGD (e.g., sulfate, Zn, Pb, and Cu) have also changed relative to existing data. The end-tail emission factors (EFs) of PM2.5, PM10, and PMtotal under the typical ULE technical routes of WESP are calculated in time, and the corresponding EFs are in the range of 2.82–8.97, 15.7–27.6, and 38.6–61.7 g t−1, respectively. We believe the latest detailed PM EFs and the associated chemical profiles provided in this study are more representative of the current emission situations of Chinese CFPPs.
- Published
- 2019
27. Spatial-temporal variation characteristics of air pollution in Henan of China: Localized emission inventory, WRF/Chem simulations and potential source contribution analysis
- Author
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Yan Hao, Shuhan Liu, Hezhong Tian, Shenbing Hua, Yifeng Xue, Huanjia Liu, Bobo Wu, Peipei Qiu, Xiangyang Liu, Kun Wang, Pangyang Shao, and Yiming Wu
- Subjects
Pollution ,Pollutant ,education.field_of_study ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Urban agglomeration ,media_common.quotation_subject ,Population ,Air pollution ,010501 environmental sciences ,medicine.disease_cause ,Atmospheric sciences ,01 natural sciences ,Weather Research and Forecasting Model ,medicine ,Environmental Chemistry ,Environmental science ,Spatial variability ,Emission inventory ,education ,Waste Management and Disposal ,0105 earth and related environmental sciences ,media_common - Abstract
Henan is the most populous province and one of the most seriously polluted areas in China at present. In this study, we establish an integrated atmospheric emission inventory of primary air pollutants in Henan province for the target year of 2012. The inventory developed here accounts for detailed activity levels of 11 categories of primary anthropogenic emission sources, and determines the best available representation of emission factors. Further, we allocate the annual emissions into a high spatial resolution of 3km×3km with ArcGIS methodology and surrogate indices, such as regional population distribution and gross domestic product (GDP). Our results show that the emissions of VOCs, SO2, PM10, PM2.5, NOX, NH3, CO, BC and OC are about 1.15, 1.24, 1.29, 0.70, 1.93, 1.05, 7.92, 0.27 and 0.25milliontons, respectively. The majority of these pollutant emissions comes from the Central Plain Urban Agglomeration (CPUA) region, particularly Zhengzhou and Pingdingshan. By combining with the emission inventory with the WRF/Chem modeling and backward trajectory analysis, we investigate the temporal and spatial variability of air pollution in the province and explore the causes of higher pollutants concentrations in the region of CPUA during the heavily polluted period of January. The results demonstrate that intensive pollutants emissions and unfavorable meteorological conditions are the main causes of the heavy pollution. Besides, Weighted Potential Source Contribution Function (WPSCF) analysis indicates that local emissions remain the major contributor of PM2.5 in Henan province, although emissions from the neighboring provinces (e.g. Shanxi, Shaanxi, Anhui, and Shandong) are also important contributors.
- Published
- 2018
28. Erythrocytes-based quartz crystal microbalance cytosensor for in situ detection of cell surface sialic acid
- Author
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Peihui Yang, Lin Zhou, Yan Hao, Bin Zhou, and Xiaojuan Yang
- Subjects
In situ ,Detection limit ,Glycan ,Chromatography ,biology ,Chemistry ,Analytical chemistry ,Nanoprobe ,02 engineering and technology ,Quartz crystal microbalance ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Analytical Chemistry ,Sialic acid ,chemistry.chemical_compound ,Colloidal gold ,Concanavalin A ,Electrochemistry ,biology.protein ,Environmental Chemistry ,0210 nano-technology ,Spectroscopy - Abstract
An erythrocytes (RBCs) cytosensor was first fabricated for in situ analysis of sialic acid (SA) on the cell surface based on a quartz crystal microbalance (QCM). RBCs, as a recognition element, were immobilized on a concanavalin A (ConA)-modified gold chip through the specific recognition between ConA and mannose on the cell surface. 4-Aminobenzeneboronic acid (APBA)-functionalized gold nanoparticles (AuNPs/APBA) were used as a signal amplification nanoprobe for labeling SA on the surface of RBCs. Compared to that of APBA, the frequency response of the cytosensor could be significantly enhanced 18-fold by using a AuNPs/APBA nanoprobe. RBCs can be detected in the range of 2.6 × 103 to 7.2 × 106 cells per mL with a detection limit of 1.1 × 103 cells per mL. The proposed cytosensor was further applied to detect the expression level of SA on normal and diabetic RBCs in situ, which showed that the average number of SA expressed on single normal and diabetic RBC surfaces were 2.1 ± 0.2 × 108 and 8.2 ± 0.7 × 107 with a relative standard deviation of 4.3% and 3.6%, respectively. The strategy shows an in situ and high sensitivity method for the quantitative evaluation of SA expression on RBC surface and provides a new alternative methodology to analyze glycan expression at the cell surface.
- Published
- 2017
29. Seasonal variations in the mass characteristics and optical properties of carbonaceous constituents of PM2.5 in six cities of North China
- Author
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Yan Hao, Bobo Wu, Xiaoxuan Bai, Wei Liu, Shumin Lin, Shuhan Liu, Lining Luo, Shuang Zhao, Huanjia Liu, Jiming Hao, Kai Zhang, Yujiao Sun, and Hezhong Tian
- Subjects
Total organic carbon ,Pollution ,010504 meteorology & atmospheric sciences ,Contribution function ,Health, Toxicology and Mutagenesis ,media_common.quotation_subject ,North china ,Climate change ,General Medicine ,Carbon black ,010501 environmental sciences ,Toxicology ,01 natural sciences ,Beijing ,Environmental chemistry ,Environmental science ,Brown carbon ,0105 earth and related environmental sciences ,media_common - Abstract
Carbonaceous constituents have various adverse impacts on human health, visibility, and climate change. Although comprehensive studies on the characteristics of carbonaceous constituents have been conducted recently, systematic studies covering both the mass characteristics and light-absorption properties of carbonaceous constituents on a regional scale in China are quite limited. In this study, current seasonal measurements of organic carbon (OC) and elemental carbon (EC) in PM2.5 were investigated during autumn and winter (1–30 October 2017 and December 18, 2017 to January 17, 2018) in six selected cities located at the eastern foot of the Taihang Mountains: Beijing, Baoding, Shijiazhuang, Handan, Xinxiang, and Zhengzhou. Seasonal variations were similar when Beijing was excluded. The lowest concentrations of OC (18.33 ± 9.39 μg/m3) and EC (7.66 ± 5.64 μg/m3) were observed in Xinxiang (autumn) and Beijing (winter), respectively, while the highest concentrations of OC (38.43 ± 62.10 μg/m3) and EC (12.24 ± 24.67 μg/m3) occurred in Baoding during winter mainly due to elevated fuel combustion for space heating. The results of the potential source contribution function (PSCF) analysis suggested that border zones between several provinces in North China should be highlighted in order to strengthen pollution control. Moreover, by separating the optical properties of brown carbon from those of black carbon, we were able to estimate the contributions of brown carbon to the PM2.5 total light-absorption coefficient. The results show that the brown carbon absorption coefficient (at 405 nm) in winter at six sites accounted for 21.2%, 33.3%, 34.7%, 39.1%, 48.6%, and 23.3% of the PM2.5 light absorption, which are values that are comparable to the contribution of black carbon in Xinxiang. These results provide a more comprehensive understanding of carbonaceous constituents on a regional scale.
- Published
- 2021
30. Refined assessment of size-fractioned particulate matter (PM2.5/PM10/PMtotal) emissions from coal-fired power plants in China
- Author
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Yujiao Sun, Yan Hao, Shuang Zhao, Wei Liu, Bobo Wu, Hezhong Tian, Zhihui Guo, Shuhan Liu, Xiaoxuan Bai, Jiming Hao, Lining Luo, Shumin Lin, and Chuanyong Zhu
- Subjects
Environmental Engineering ,010504 meteorology & atmospheric sciences ,Environmental engineering ,Field tests ,010501 environmental sciences ,Particulates ,Coal fired ,01 natural sciences ,Pollution ,Two stages ,Environmental Chemistry ,Environmental science ,Retrofitting ,Integrated database ,Emission inventory ,Waste Management and Disposal ,Air quality index ,0105 earth and related environmental sciences - Abstract
Chinese coal-fired power plants (CFPPs) are experiencing large-scale and rapid retrofitting of ultralow emission (ULE), causing significant changes in emission level of particulate matter (PM) from CFPPs. In this study, based on coal ash mass balance over the whole process, an integrated emission factors (EFs) database of three size-fractioned particulate matters (PM2.5, PM10, and PMtotal) for CFPPs is constructed, which covers almost all typical ULE technical routes installed in CFPPs. To verify the reliability of PM EFs established in this study, we compare those with related results based on field tests. Overall, the gaps in the EFs of PM2.5, PM10, and PMtotal obtained by the two methods are not outrageous within a reasonable range. By combined with the refined size-fractioned PM EFs and unit-based activity level database, a detailed high-resolution emission inventory of PM2.5, PM10, and PMtotal from Chinese CFPPs in 2017 is established, with the corresponding total emissions of 143, 207, and 267 kt, respectively. Our estimation of PMtotal emission is comparable to the official statistics announced by China Electricity Council (CEC), which further demonstrates the reliability of PM EFs constructed in this study. Moreover, potential reductions of PM from CFPPs at two stages before and after 2017 are assessed under three application scenarios of major ULE technical routes. We forecast the final annual emissions of PM2.5, PM10, and PMtotal until 2020 will be reduced further, which fall within the range of 86-111 kt, 120-157 kt, and 142-184 kt, respectively, if all CFPPs achieve ULE requirements under the three scenarios. We believe our integrated database of PM EFs of CFPPs has good universality, and the forecast results will be helpful for policy guidance of ULE technologies, emissions inventory compilation, and regional air quality simulation and management.
- Published
- 2020
31. The significant effect of octa(aminophenyl)silsesquioxane on the electrospun ion-selective and ultra-strong poly-m-phenyleneisophthalamide separator for enhanced electrochemical performance of lithium-sulfur battery
- Author
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Yan Hao, Nanping Deng, Yaofang Zhang, Huijuan Zhao, Gang Wang, Bowen Cheng, and Weimin Kang
- Subjects
Materials science ,General Chemical Engineering ,Nanoparticle ,Lithium–sulfur battery ,02 engineering and technology ,General Chemistry ,Electrolyte ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Industrial and Manufacturing Engineering ,Silsesquioxane ,Electrospinning ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Environmental Chemistry ,0210 nano-technology ,Polysulfide ,Separator (electricity) - Abstract
In this paper, a novel ion-selective and ultra-strong poly-m-phenyleneisophthalamide (PMIA)-based gel polymer electrolyte (GPE) containing fluorinated emulsion and octa(aminophenyl)silsesquioxane (OAPS) nanoparticles is rationally designed for lithium-sulfur batteries by electrospinning. Under the significant effect of OAPS, the PMIA-based GPE acts as a multi-functional separator with exceedingly high electrolyte uptake, exceptional thermal stability and robust mechanical strength. Particularly, the -NH2 groups of OAPS provide an electronegative environment, which facilitate the lithium ions migration while inhibit the negative polysulfide anions transfer. Thus, the PMIA-based GPE exhibits an effective electrostatic shielding effect to restrain lithium polysulfide on cathode side, while vigorously stimulating the transmission of lithium ions. As a great result, the lithium ions migration, the interface impedance and the reversible rate capacity of the assembled lithium-sulfur battery obtain a marked improvement. Meantime, the cell with the PMIA-based separator, adopting conventional sulfur-carbon black as cathode materials, delivers a high initial capacity of 851.1 mAh·g−1 with capacity retention of 458.3 mAh·g−1 after 800 cycles at 0.5 C rate, accompanied by a low capacity decay of 0.057% per cycle. Therefore, the prepared PMIA separator imbedding with OAPS can be deemed as an extraordinary potential candidate for the application in high-performance lithium-sulfur cells.
- Published
- 2020
32. Atmospheric emission inventory of multiple pollutants from civil aviation in China: Temporal trend, spatial distribution characteristics and emission features analysis
- Author
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Yan Hao, Xiaoxuan Bai, Yiming Wu, Bobo Wu, Chuanyong Zhu, Wei Liu, Huanjia Liu, Hezhong Tian, Xiangyang Liu, and Shuhan Liu
- Subjects
Pollutant ,education.field_of_study ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Population ,Cruise ,Civil aviation ,010501 environmental sciences ,engineering.material ,Atmospheric sciences ,01 natural sciences ,Pollution ,Domestic flight ,engineering ,Environmental Chemistry ,Environmental science ,Aviation fuel ,Emission inventory ,education ,Waste Management and Disposal ,NOx ,0105 earth and related environmental sciences - Abstract
A detailed comprehensive emission inventory of multiple air pollutants from civil aviation in China for the historical period of 1980–2015 is developed by using an approach of combining bottom-up with top-down for the first time. Annual emissions of various pollutants present a rapidly ascending trend along with the increase of economic volume and population, which are estimated at approximately 4.77 kt HC, 59.63 kt CO, 304.77 kt NOx, 59,961 kt CO2, 19.04 kt SO2, 3.32 kt PM2.5, 1.59 kt BC, 1.06 kt OC and 5.44 t heavy metals (HMs), respectively, by the year 2015. We estimate the local emissions in 208 domestic civil airports and allocate the total cruise emissions onto 299 main domestic flight segments with surrogate indexes, such as route distance, cargo and passenger turnover. The results demonstrate that emission intensities in central and eastern China are much higher than those in northeastern and western China, and these regions are characterized with high population density, huge economy volume, as well as transit convenience. Furthermore, we have explored emission characteristics of multiple pollutants under different operation modes in 2015. For PM2.5, SO2/CO2/HMs and NOx, the emissions from cruise process constitute the dominant contributor with a share of 89%, 92% and 81%, of the associated total emissions, respectively, comparing with 76% and 71% of the total CO and HC emissions release from Landing and Take-off (LTO) process. Consequently, there are notably different emission characteristics from different flight processes due to various combustion status of aviation fuel. In addition, we predict the future trends of multi-pollutants emissions from China's civil aviation industry through 2050 under three scenarios, and the results indicate that the reduction from the improvement of new technology or new national standards would be largely offset by the rise in multi-pollutants emissions from rapidly aviation fuel growth.
- Published
- 2018
33. Electrolytes Based on TEMPO–Co Tandem Redox Systems Outperform Single Redox Systems in Dye‐sensitized Solar Cells
- Author
-
Gerrit Boschloo, Yan Hao, Jiayan Cong, and Lars Kloo
- Subjects
General Chemical Engineering ,Photoelectrochemistry ,Inorganic chemistry ,tandem‐redox ,Electrolyte ,electrolyte ,Redox ,law.invention ,photoelectrochemistry ,Cyclic N-Oxides ,Electric Power Supplies ,law ,redox chemistry ,Solar cell ,Solar Energy ,Environmental Chemistry ,Molecule ,General Materials Science ,Coloring Agents ,Tandem ,Chemistry ,Communication ,Energy conversion efficiency ,Cobalt ,humanities ,Communications ,solar cell ,Corrosion ,Dye-sensitized solar cell ,General Energy ,Oxidation-Reduction - Abstract
A new TEMPO–Co tandem redox system with TEMPO and Co(bpy)3 2+/3+ has been investigated for the use in dye‐sensitized solar cells (DSSCs). A large open‐circuit voltage (V OC) increase, from 862 mV to 965 mV, was observed in the tandem redox system, while the short‐circuit current density (J SC) was maintained. The conversion efficiency was observed to increase from 7.1 % for cells containing the single Co(bpy)3 2+/3+ redox couple, to 8.4 % for cells containing the TEMPO–Co tandem redox system. The reason for the increase in V OC and overall efficiency is ascribed to the involvement of partial regeneration of the sensitizing dye molecules by TEMPO. This assumption can be verified through the observed much faster regeneration dynamics exhibited in the presence of the tandem system. Using the tandem redox system, the faster recombination problem of the single TEMPO redox couple is resolved and the mass‐transport of the metal‐complex‐based electrolyte is also improved. This TEMPO–Co tandem system is so far the most effienct tandem redox electrolyte reported not involving iodine. The current results show a promising future for tandem system as replacements for single redox systems in electrolytes for DSSCs.
- Published
- 2014
34. The degradation of EDTA by the bimetallic Fe–Cu/O2 system
- Author
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Luming Ma, Jinhong Fan, Xin Liu, and Yan Hao
- Subjects
In situ ,General Chemical Engineering ,Advanced oxidation process ,Inorganic chemistry ,Ethylenediaminetetraacetic acid ,General Chemistry ,Industrial and Manufacturing Engineering ,Catalysis ,chemistry.chemical_compound ,Residue (chemistry) ,chemistry ,Environmental Chemistry ,Hydroxyl radical ,Spectroscopy ,Bimetallic strip - Abstract
The bimetallic Fe–Cu/O 2 process exhibited significantly higher reactivity than did the Fe/O 2 process for the degradation of ethylenediaminetetraacetic acid (EDTA). With the analysis of the soluble Cu 2+ in the solution and decomposition of H 2 O 2 catalyzed by Cu 0 , possible enhanced-pathways at different pHs were suggested. The degradation efficiency of EDTA increased with decreasing initial pH ranging 3–9, however, the reactions proceeded at a weakly-basic to basic condition in most of the reaction time. POD inhibition test showed that in situ generation of H 2 O 2 played a pivotal role in the EDTA degradation, however, the instant concentration analyzed by DPD–POD method was less than 4.5 μM due to rapid subsequent Fenton reaction. Furthermore, DMPO–ESR spectroscopy and BA-trapping experiments detected the in situ generation of OH. The mechanism of EDTA oxidative degraded by the bimetallic Fe–Cu/O 2 process was verified using control experiments of absorption, stripping, and coagulation sedimentation of EDTA in the system, analysis of solid residue, oxidation of O 2 and H 2 O 2 , as well as detection of H 2 O 2 and OH.
- Published
- 2014
35. Study on Membrane Fouling of a Hydrogen-Based Membrane Biofilm Reactor Treating Nitrate-Contaminated Drinking Water
- Author
-
Gang Li, Gao Lei, Jun Yu, Hua Zhang, and Yan Hao Zhang
- Subjects
chemistry.chemical_compound ,Denitrification ,Membrane ,Nitrate ,chemistry ,Sedimentation (water treatment) ,Hollow fiber membrane ,Environmental chemistry ,Membrane fouling ,Biofilm ,Environmental engineering ,General Medicine ,Polyethylene - Abstract
A hollow fiber membrane biofilm reactor (MBfR) using Polyethylene (PE) membranes was investigated for denitrification in nitrate-contimanitated drinking water. The reactor was operated over 85 days with influent nitrate loading increasing gradually. The result showed that maximum of nitrate denitrification rate achieved was 3.84 g NO3ˉ-N/m3/d (1.36 g NO3ˉ-N/m2/d) and the total nitrogen removal was more than 96%. The results also showed that the membrane pollution was mainly caused by the mineral sedimentation and EPS.
- Published
- 2013
36. Research on Characteristics Recognition of Organic Matter in Yellow River Reservoir Water
- Author
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Jian Guang Liu, Kai Li, Hui Liu, Meng Meng Feng, and Yan Hao Zhang
- Subjects
chemistry.chemical_classification ,General Engineering ,Environmental engineering ,Ultrafiltration ,Biodegradation ,Adsorption ,chemistry ,Reservoir water ,Environmental chemistry ,Dissolved organic carbon ,Environmental science ,Water treatment ,Organic matter ,Raw water - Abstract
Six water samples from different Yellow River reservoirs in Shandong were selected. The molecular weight distribution and type of organic matter were determined by using ultrafiltration, adsorption experiments and active bio-sand determination methods. The results show that the proportions of TOC and UV254Subscript text in different molecular weight intervals and the type of organic matter are different. But the proportion of adsorbable dissolved organic matter is the largest, which is more than 80%.In addition, the proportion of biodegradable organic matter (BDOC) is little, so the biodegradability of the raw water is not high.
- Published
- 2011
37. Comparative studies on rigid π linker-based organic dyes: structure-property relationships and photovoltaic performance
- Author
-
Hairong Li, Anders Hagfeldt, Andrew C. Grimsdale, Yuichiro Abe, Feng Zhou, Haibin Su, Yan Hao, Teck Ming Koh, School of Materials Science & Engineering, and Energy Research Institute @ NTU (ERI@N)
- Subjects
Charge separation ,General Chemical Engineering ,Photovoltaic system ,Coloring agents ,Structure property ,Electrochemistry ,chemistry.chemical_compound ,Structure-Activity Relationship ,General Energy ,chemistry ,Computational chemistry ,Science::Chemistry::Physical chemistry::Electrochemistry [DRNTU] ,Thiophene ,Environmental Chemistry ,Organic chemistry ,General Materials Science ,Cyclic voltammetry ,Organic Chemicals ,Coloring Agents ,Linker - Abstract
© 2014 Wiley-VCH Verlag GmbH & Co. KGaA. A series of six structurally correlated donor-π bridge-acceptor organic dyes were designed, synthesized, and applied as sensitizers in dye-sensitized solar cells. Using the most widely studied donor (triarylamine) and cyclopenta[1,2-b:5,4-b′]dithiophene or cyclopenta[1,2-b:5,4-b′]dithiophene[2′,1′:4,5]thieno-[2,3-d]thiophene as π spacers, their structure-property relationships were investigated in depth by photophysical techniques and theoretical calculations. It was found that the photovoltaic performance of these dyes largely depends on their electronic structures, which requires synergistic interaction between donors and acceptors. Increasing the electron richness of the donor or the elongation of π-conjugated bridges does not necessarily lead to higher performance. Rather, it is essential to rationally design the dyes by balancing their light-harvesting capability with achieving suitable energy levels to guarantee unimpeded charge separation and transport.
- Published
- 2014
38. Interactions between heavy metal lead and two freshwater algae
- Author
-
李诚 Li Cheng, 周杨 Zhou Yang, 李源 Li Yuan, 张庭廷 Zhang Tingting, 闫浩 Yan Hao, and 刘璐 Liu Lu
- Subjects
Metal ,Freshwater algae ,Lead (geology) ,Ecology ,Chemistry ,visual_art ,Environmental chemistry ,visual_art.visual_art_medium ,Ecology, Evolution, Behavior and Systematics - Published
- 2014
39. Recyclable copper catalysts based on imidazolium-tagged C2-symmetric bis(oxazoline) and their application in D–A reactions in ionic liquids
- Author
-
Zhi-Huai Li, Jin-Liang Wang, Zhiming Zhou, Xiao Dong, Jun Zhang, Li Dai, Xia Li, Haifeng Huang, Ying-Qiang Liu, Xin Li, and Xiao-Yan Hao
- Subjects
chemistry.chemical_compound ,Cyclopentadiene ,chemistry ,Ionic liquid ,Polymer chemistry ,Environmental Chemistry ,Organic chemistry ,chemistry.chemical_element ,Oxazoline ,Pollution ,Copper ,Catalysis ,Dichloromethane - Abstract
Functional imidazolium ionic liquids have been developed as a new class of versatile catalysts. C2-symmetric and unsymmetric imidazolium-tagged bis(oxazoline) ligands were prepared, and the anions of the ligands were altered by ion-exchange reactions. The catalysts based on the new ligands and Cu(OTf)2 were applied in asymmetric Diels–Alder reactions between N-acryloyl/N-crotonoyloxazolidinones 15 and 1,3-cyclohexandiene/cyclopentadiene 16 in different ionic liquids and in dichloromethane (DCM). The catalysts achieved a high level of activity and enantioselectivity, as well as good recyclability: cycloadduct (S)-17ab was attained at 98% conversion and 97% ee in [Bmim]NTf2. Moreover, the catalyst could be recycled 20 times without an obvious loss of activity or enantioselectivity. By comparison, we deduced that the C2 symmetry of the new ligands was crucial for obtaining high ee values. Toxicity studies of the ligands were performed for the first time.
- Published
- 2011
40. Molecular Design to Improve the Performance of Donor-π Acceptor Near-IR Organic Dye-Sensitized Solar Cells
- Author
-
Xichuan Yang, Yan Hao, Xiuna Wang, Jiayan Cong, Meizhen Zhou, Anders Hagfeldt, and Licheng Sun
- Subjects
Infrared ,Infrared Rays ,General Chemical Engineering ,Nanoparticle ,Photochemistry ,Electric Power Supplies ,mol design donor acceptor complex solar cell ,Solar Energy ,Environmental Chemistry ,General Materials Science ,Organic Chemicals ,Coloring Agents ,Photocurrent ,Chemistry ,business.industry ,Energy conversion efficiency ,Solar energy ,Acceptor ,Carbon ,General Energy ,Semiconductor ,Semiconductors ,Nanoparticles ,business ,Recombination ,dye sensitized solar cell donor acceptor complex - Abstract
A novel near-IR charge-transfer complex, as a D-π-A-type mol., has a lateral anchoring group and a flexible long carbon chain that replaces the Me group of the donor part of the mol. This carbon chain seems to prevent the formation of mol. aggregates on the semiconductor (TiO2) nanoparticles, thus blocking charge recombination at relatively high open-circuit voltages and short-circuit photocurrent densities. This sensitizer dye has a max. IPCE (incident-photon-to-current conversion efficiencies) of 93% at 660 nm and an overall solar-energy-to-electricity conversion efficiency of 5.1%.
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