The Experts below are selected from a list of 92460 Experts worldwide ranked by ideXlab platform
He-zhong Tian - One of the best experts on this subject based on the ideXlab platform.
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global anthropogenic Atmospheric Emission inventory of twelve typical hazardous trace elements 1995 2012
Atmospheric Environment, 2020Co-Authors: He-zhong Tian, Chuanyong Zhu, Ji-ming HaoAbstract:Abstract Hazardous trace elements (HTEs) cannot be eliminated through microbial degradation in the environment, and moreover, high concentrations of HTEs do not only impose a long term and non-reversible burden on biogeochemical cycling in the ecosystem, but also threaten the health and life of animals and human beings. Taking account of the obvious differences on economic development and technology diffusion among countries, we construct the best available representation of time-varying Emission factors of HTEs for primary anthropogenic activities in five regions of the world. Anthropogenic Atmospheric Emission inventory of twelve typical HTEs (Hg, As, Se, Pb, Cd, Cr, Ni, Sb, Mn, Co, Cu and Zn) characterized by global region, long-term spans and high spatiotemporal resolutions are elaborately established by synthetically using Emission factor methods and ArcGIS tools. Our results show that the global total Emissions of twelve HTEs from primary anthropogenic sources have decreased from about 268262 tons in 1995–216893 tons in 2012, with an annual decline rate of 1%. For HTE Emissions in 2012, coal combustion sources (CC, accounting for about 35–97% of Hg, Se, Cr, Mn, Co and Zn Emissions), liquid fuel combustion (LFC, accounting for about 31% of Pb Emission), nonferrous metal smelting (NFMS, being responsible for about 51–77% of As, Cd and Ni Emissions) and brake wear (BW, contributing about 42–67% of Sb and Cu Emissions) are identified as primary contribution sources for the corresponding HTEs. Asia is the highest HTEs emitting continent in 2012, accounting for approximately 59% of the global total Emissions. Generally, China, Chile, India, Russia, the United States and South Africa represent the top countries with high HTE Emissions from anthropogenic sources. Therein, China ranks as the world's largest country with HTE (except for Sb) Emissions. In contrast, the U.S. is found as the country producing the largest Sb Emission throughout the world. The top Emission intensities of HTEs are found in Eastern and Southern Asia and Eastern Europe.
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Atmospheric Emission inventory of multiple pollutants from civil aviation in china temporal trend spatial distribution characteristics and Emission features analysis
Science of The Total Environment, 2019Co-Authors: Huanjia Liu, He-zhong Tian, Chuanyong Zhu, Xiangyang Liu, Yan Hao, Shuhan Liu, Wei Liu, Xiaoxuan BaiAbstract: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.
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Atmospheric Emission inventory of hazardous air pollutants from china s cement plants temporal trends spatial variation characteristics and scenario projections
Atmospheric Environment, 2016Co-Authors: Shenbing Hua, He-zhong Tian, Chuanyong Zhu, Jiajia Gao, Kun Wang, Yifeng Xue, Yong Wang, Shiheng Duan, Junrui ZhouAbstract:Abstracts A multiple-year comprehensive Emission inventory of typical hazardous air pollutants (HAPs) from China's cement industry for the period 1980–2012, has been established by using technology-based dynamic Emission factors and detailed annual plant-specific cement production from different types of kilns. Our results show that the total Emissions of various HAPs (SO 2 , NO X , CO, PM, Hg, Cd, Cr, Pb, Zn, As, Ni and Cu) have rapidly increased by about 1–21 times at an annual average growth rate of 1–10% over the past three decades. Remarkably uneven spatial allocation features of these pollutants among provinces are observed. HAPs Emissions are primarily concentrated in the eastern and coastal provinces due to the concentration of cement plants and their huge volume of coal consumption. We predict the future Emission trends of HAPs through 2050 based on industry construction and policy guidance, and our scenario analysis indicates that HAPs Emissions will drop substantially because of the combined effects of cement production yields reduction and the increasing application rate of various air pollution control devices. The study suggests that highlighted attention should be paid to this energy-intensive industry to ensure stricter Emission standards are implemented for these HAPs Emissions in the future.
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Atmospheric Emission characteristics and control policies of five precedent controlled toxic heavy metals from anthropogenic sources in china
Environmental Science & Technology, 2015Co-Authors: Ke Cheng, He-zhong Tian, Chuanyong Zhu, Yan Wang, Yongxin Zhang, Xiang Gao, Jiajia GaoAbstract:A bottom-up inventory of Atmospheric Emissions of five precedent-controlled toxic heavy metals (HMs), including mercury (Hg), arsenic (As), lead (Pb), cadmium (Cd), and chromium (Cr), from primary anthropogenic sources in China is established for the period 2000–2010. Total Emissions of HMs demonstrate a gradually ascending trend along with the increase of coal consumption and industrial production, which are estimated at approximately 842.22 t for Hg, 4196.31 t for As, 29272.14 t for Pb, 795.29 t for Cd, and 13715.33 t for Cr for 2010. Coal combustion is found to be the primary source of HMs Emissions. Owing to the dramatic differences of coal use by industrial and power sectors among provinces, spatial allocation performs remarkably uneven characteristics, and spatial distribution features are demonstrated by allocating the Emissions into 0.5° × 0.5° grid cells with GDP and population as surrogate indexes. Further, HMs Emissions from specified anthropogenic sources under three different control scenario...
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Atmospheric Emission inventory of cadmium from anthropogenic sources
International Journal of Environmental Science and Technology, 2014Co-Authors: He-zhong Tian, K Cheng, Dan Zhao, Y Wang, Jing Chen, Xiangyang Liu, Wenru Jia, Zhe HuangAbstract:To demonstrate the Atmospheric Emission characteristics of cadmium (Cd), which is considered an important contaminant to human health and environment, a comprehensive Emission inventory of Cd has been established by applying the best available Emission factors and activity data for the first time. This inventory covers major anthropogenic sources in China and a bottom-up approach is adopted to compile the inventory for the sources where possible. The total Emissions of Cd are estimated at about 743.77 metric tons for the year 2009, of which the contributions of industrial processes and combustion sources are approximately 56.6 and 43.4 %, respectively. Nonferrous metals smelting including copper, lead, and zinc, ranks as the leading source accounting for about 40.6 % of the total. The high contribution results from the rapid growth of nonferrous metallurgical industry that reflects a new focus of Cd Emission pollution in China. Cd Emissions from coal combustion are estimated at approximately 273.69 metric tons, with a share of 36.8 %, in which industrial coal-burning sector is thought to be the primary source. Moreover, Cd Emissions are spatially allocated onto grid cells with a resolution of 0.5A degrees A xA 0.5A degrees, indicating that the Emissions are mainly distributed among the regions of eastern, central and southern China. In addition, the uncertainties in the inventory are quantified by using a Monte Carlo simulation, and the overall uncertainty falls within a range of -15 to 48 %. It implies that more field tests for industrial coal combustion and metals smelting process are very necessary.
Chuanyong Zhu - One of the best experts on this subject based on the ideXlab platform.
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global anthropogenic Atmospheric Emission inventory of twelve typical hazardous trace elements 1995 2012
Atmospheric Environment, 2020Co-Authors: He-zhong Tian, Chuanyong Zhu, Ji-ming HaoAbstract:Abstract Hazardous trace elements (HTEs) cannot be eliminated through microbial degradation in the environment, and moreover, high concentrations of HTEs do not only impose a long term and non-reversible burden on biogeochemical cycling in the ecosystem, but also threaten the health and life of animals and human beings. Taking account of the obvious differences on economic development and technology diffusion among countries, we construct the best available representation of time-varying Emission factors of HTEs for primary anthropogenic activities in five regions of the world. Anthropogenic Atmospheric Emission inventory of twelve typical HTEs (Hg, As, Se, Pb, Cd, Cr, Ni, Sb, Mn, Co, Cu and Zn) characterized by global region, long-term spans and high spatiotemporal resolutions are elaborately established by synthetically using Emission factor methods and ArcGIS tools. Our results show that the global total Emissions of twelve HTEs from primary anthropogenic sources have decreased from about 268262 tons in 1995–216893 tons in 2012, with an annual decline rate of 1%. For HTE Emissions in 2012, coal combustion sources (CC, accounting for about 35–97% of Hg, Se, Cr, Mn, Co and Zn Emissions), liquid fuel combustion (LFC, accounting for about 31% of Pb Emission), nonferrous metal smelting (NFMS, being responsible for about 51–77% of As, Cd and Ni Emissions) and brake wear (BW, contributing about 42–67% of Sb and Cu Emissions) are identified as primary contribution sources for the corresponding HTEs. Asia is the highest HTEs emitting continent in 2012, accounting for approximately 59% of the global total Emissions. Generally, China, Chile, India, Russia, the United States and South Africa represent the top countries with high HTE Emissions from anthropogenic sources. Therein, China ranks as the world's largest country with HTE (except for Sb) Emissions. In contrast, the U.S. is found as the country producing the largest Sb Emission throughout the world. The top Emission intensities of HTEs are found in Eastern and Southern Asia and Eastern Europe.
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Atmospheric Emission inventory of multiple pollutants from civil aviation in china temporal trend spatial distribution characteristics and Emission features analysis
Science of The Total Environment, 2019Co-Authors: Huanjia Liu, He-zhong Tian, Chuanyong Zhu, Xiangyang Liu, Yan Hao, Shuhan Liu, Wei Liu, Xiaoxuan BaiAbstract: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.
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Atmospheric Emission inventory of hazardous air pollutants from china s cement plants temporal trends spatial variation characteristics and scenario projections
Atmospheric Environment, 2016Co-Authors: Shenbing Hua, He-zhong Tian, Chuanyong Zhu, Jiajia Gao, Kun Wang, Yifeng Xue, Yong Wang, Shiheng Duan, Junrui ZhouAbstract:Abstracts A multiple-year comprehensive Emission inventory of typical hazardous air pollutants (HAPs) from China's cement industry for the period 1980–2012, has been established by using technology-based dynamic Emission factors and detailed annual plant-specific cement production from different types of kilns. Our results show that the total Emissions of various HAPs (SO 2 , NO X , CO, PM, Hg, Cd, Cr, Pb, Zn, As, Ni and Cu) have rapidly increased by about 1–21 times at an annual average growth rate of 1–10% over the past three decades. Remarkably uneven spatial allocation features of these pollutants among provinces are observed. HAPs Emissions are primarily concentrated in the eastern and coastal provinces due to the concentration of cement plants and their huge volume of coal consumption. We predict the future Emission trends of HAPs through 2050 based on industry construction and policy guidance, and our scenario analysis indicates that HAPs Emissions will drop substantially because of the combined effects of cement production yields reduction and the increasing application rate of various air pollution control devices. The study suggests that highlighted attention should be paid to this energy-intensive industry to ensure stricter Emission standards are implemented for these HAPs Emissions in the future.
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Atmospheric Emission characteristics and control policies of five precedent controlled toxic heavy metals from anthropogenic sources in china
Environmental Science & Technology, 2015Co-Authors: Ke Cheng, He-zhong Tian, Chuanyong Zhu, Yan Wang, Yongxin Zhang, Xiang Gao, Jiajia GaoAbstract:A bottom-up inventory of Atmospheric Emissions of five precedent-controlled toxic heavy metals (HMs), including mercury (Hg), arsenic (As), lead (Pb), cadmium (Cd), and chromium (Cr), from primary anthropogenic sources in China is established for the period 2000–2010. Total Emissions of HMs demonstrate a gradually ascending trend along with the increase of coal consumption and industrial production, which are estimated at approximately 842.22 t for Hg, 4196.31 t for As, 29272.14 t for Pb, 795.29 t for Cd, and 13715.33 t for Cr for 2010. Coal combustion is found to be the primary source of HMs Emissions. Owing to the dramatic differences of coal use by industrial and power sectors among provinces, spatial allocation performs remarkably uneven characteristics, and spatial distribution features are demonstrated by allocating the Emissions into 0.5° × 0.5° grid cells with GDP and population as surrogate indexes. Further, HMs Emissions from specified anthropogenic sources under three different control scenario...
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Atmospheric Emission inventory of hazardous trace elements from China's coal-fired power plants-temporal trends and spatial variation characteristics
Environmental Science and Technology, 2014Co-Authors: He-zhong Tian, Kaiyun Liu, Junrui Zhou, Ji-ming Hao, Peipei Qiu, Chuanyong Zhu, Long Lu, Jiajia Gao, Kun Wang, Shenbing HuaAbstract:Coal-fired power plants are the important sources of anthropogenic Atmospheric releases of various hazardous trace elements (HTE) because a large quantity of Emissions can cause wide dispersion and possible long-distance transportation. To obtain the temporal trends and spatial variation characteristics of various HTE discharged from coal-fired power plants of China, a multiple-year comprehensive Emission inventory of HTE including Hg, As, Se, Pb, Cd, Cr, Ni, and Sb has been established for the period 2000?2010. Thanks to the cobenefit removal effects of conventional particulate matter/sulfur dioxide/nitrogen oxides (PM/SO2/NOx) control devices, Emissions of these 8 toxic elements have shown a gradual decline since the peak in 2006. The total Emissions of Hg, As, Se, Pb, Cd, Cr, Ni, and Sb are substantial and are estimated at about 118.54, 335.45, 459.4, 705.45, 13.34, 505.03, 446.42, and 82.33 tons (t), respectively, in 2010. Shandong, Jiangsu, Shanxi, and Hebei always rank among the top ten provinces with the highest Emissions. Further, future Emissions for 2015 and 2020 are projected with scenario analysis. Advanced technologies and integrated management strategies to control HTE are in great need.
Aamir Ali - One of the best experts on this subject based on the ideXlab platform.
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two year cosmology large angular scale surveyor class observations a first detection of Atmospheric circular polarization at q band
The Astrophysical Journal, 2020Co-Authors: Matthew Petroff, Kathleen Harrington, Aamir Ali, John W. Appel, Charles L. Bennett, Joseph Eimer, Michael K Brewer, Ricardo BustosAbstract:The Earth's magnetic field induces Zeeman splitting of the magnetic dipole transitions of molecular oxygen in the atmosphere, which produces polarized Emission in the millimeter-wave regime. This polarized Emission is primarily circularly polarized and manifests as a foreground with a dipole-shaped sky pattern for polarization-sensitive ground-based cosmic microwave background experiments, such as the Cosmology Large Angular Scale Surveyor (CLASS), which is capable of measuring large angular scale circular polarization. Using Atmospheric Emission theory and radiative transfer formalisms, we model the expected amplitude and spatial distribution of this signal and evaluate the model for the CLASS observing site in the Atacama Desert of northern Chile. Then, using two years of observations at 32.3 GHz to 43.7 GHz from the CLASS Q-band telescope, we present a detection of this signal and compare the observed signal to that predicted by the model. We recover an angle between magnetic north and true north of $(-5.5 \pm 0.6)^\circ$, which is consistent with the expectation of $-5.9^\circ$ for the CLASS observing site. When comparing dipole sky patterns fit to both simulated and data-derived sky maps, the dipole directions match to within a degree, and the measured amplitudes match to within ${\sim}20\%$.
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The Cosmology Large Angular Scale Surveyor
Millimeter Submillimeter and Far-Infrared Detectors and Instrumentation for Astronomy VIII, 2016Co-Authors: Kathleen Harrington, Tobias A. Marriage, Aamir Ali, John W. Appel, Charles L. Bennett, Fletcher Boone, Michael Brewer, Manwei Chan, David T. Chuss, Felipe ColazoAbstract:The Cosmology Large Angular Scale Surveyor (CLASS) is a four telescope array designed to characterize relic primordial gravitational waves from in ation and the optical depth to reionization through a measurement of the polarized cosmic microwave background (CMB) on the largest angular scales. The frequencies of the four CLASS telescopes, one at 38 GHz, two at 93 GHz, and one dichroic system at 145/217 GHz, are chosen to avoid spectral regions of high Atmospheric Emission and span the minimum of the polarized Galactic foregrounds: synchrotron Emission at lower frequencies and dust Emission at higher frequencies. Low-noise transition edge sensor detectors and a rapid front-end polarization modulator provide a unique combination of high sensitivity, stability, and control of systematics. The CLASS site, at 5200 m in the Chilean Atacama desert, allows for daily mapping of up to 70% of the sky and enables the characterization of CMB polarization at the largest angular scales. Using this combination of a broad frequency range, large sky coverage, control over systematics, and high sensitivity, CLASS will observe the reionization and recombination peaks of the CMB E- and B-mode power spectra. CLASS will make a cosmic variance limited measurement of the optical depth to reionization and will measure or place upper limits on the tensor-to-scalar ratio, r, down to a level of 0.01 (95% C.L.).
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class the cosmology large angular scale surveyor
arXiv: Instrumentation and Methods for Astrophysics, 2014Co-Authors: Thomas Essingerhileman, Aamir Ali, John W. Appel, Charles L. Bennett, Fletcher Boone, Manwei Chan, M Amiri, Derek Araujo, Hsiaomei Cho, David T. ChussAbstract:The Cosmology Large Angular Scale Surveyor (CLASS) is an experiment to measure the signature of a gravita-tional-wave background from inflation in the polarization of the cosmic microwave background (CMB). CLASS is a multi-frequency array of four telescopes operating from a high-altitude site in the Atacama Desert in Chile. CLASS will survey 70\% of the sky in four frequency bands centered at 38, 93, 148, and 217 GHz, which are chosen to straddle the Galactic-foreground minimum while avoiding strong Atmospheric Emission lines. This broad frequency coverage ensures that CLASS can distinguish Galactic Emission from the CMB. The sky fraction of the CLASS survey will allow the full shape of the primordial B-mode power spectrum to be characterized, including the signal from reionization at low $\ell$. Its unique combination of large sky coverage, control of systematic errors, and high sensitivity will allow CLASS to measure or place upper limits on the tensor-to-scalar ratio at a level of $r=0.01$ and make a cosmic-variance-limited measurement of the optical depth to the surface of last scattering, $\tau$.
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class the cosmology large angular scale surveyor
Proceedings of SPIE, 2014Co-Authors: Thomas Essingerhileman, Aamir Ali, John W. Appel, Charles L. Bennett, Fletcher Boone, Manwei Chan, M Amiri, Derek Araujo, Hsiaomei Cho, David T. ChussAbstract:The Cosmology Large Angular Scale Surveyor (CLASS) is an experiment to measure the signature of a gravitational wave background from inflation in the polarization of the cosmic microwave background (CMB). CLASS is a multi-frequency array of four telescopes operating from a high-altitude site in the Atacama Desert in Chile. CLASS will survey 70% of the sky in four frequency bands centered at 38, 93, 148, and 217 GHz, which are chosen to straddle the Galactic-foreground minimum while avoiding strong Atmospheric Emission lines. This broad frequency coverage ensures that CLASS can distinguish Galactic Emission from the CMB. The sky fraction of the CLASS survey will allow the full shape of the primordial B-mode power spectrum to be characterized, including the signal from reionization at low-length. Its unique combination of large sky coverage, control of systematic errors, and high sensitivity will allow CLASS to measure or place upper limits on the tensor-to-scalar ratio at a level of r = 0:01 and make a cosmic-variance-limited measurement of the optical depth to the surface of last scattering, tau. (c) (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Kathleen Harrington - One of the best experts on this subject based on the ideXlab platform.
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two year cosmology large angular scale surveyor class observations a first detection of Atmospheric circular polarization at q band
The Astrophysical Journal, 2020Co-Authors: Matthew Petroff, Kathleen Harrington, Aamir Ali, John W. Appel, Charles L. Bennett, Joseph Eimer, Michael K Brewer, Ricardo BustosAbstract:The Earth's magnetic field induces Zeeman splitting of the magnetic dipole transitions of molecular oxygen in the atmosphere, which produces polarized Emission in the millimeter-wave regime. This polarized Emission is primarily circularly polarized and manifests as a foreground with a dipole-shaped sky pattern for polarization-sensitive ground-based cosmic microwave background experiments, such as the Cosmology Large Angular Scale Surveyor (CLASS), which is capable of measuring large angular scale circular polarization. Using Atmospheric Emission theory and radiative transfer formalisms, we model the expected amplitude and spatial distribution of this signal and evaluate the model for the CLASS observing site in the Atacama Desert of northern Chile. Then, using two years of observations at 32.3 GHz to 43.7 GHz from the CLASS Q-band telescope, we present a detection of this signal and compare the observed signal to that predicted by the model. We recover an angle between magnetic north and true north of $(-5.5 \pm 0.6)^\circ$, which is consistent with the expectation of $-5.9^\circ$ for the CLASS observing site. When comparing dipole sky patterns fit to both simulated and data-derived sky maps, the dipole directions match to within a degree, and the measured amplitudes match to within ${\sim}20\%$.
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The Cosmology Large Angular Scale Surveyor
Millimeter Submillimeter and Far-Infrared Detectors and Instrumentation for Astronomy VIII, 2016Co-Authors: Kathleen Harrington, Tobias A. Marriage, Aamir Ali, John W. Appel, Charles L. Bennett, Fletcher Boone, Michael Brewer, Manwei Chan, David T. Chuss, Felipe ColazoAbstract:The Cosmology Large Angular Scale Surveyor (CLASS) is a four telescope array designed to characterize relic primordial gravitational waves from in ation and the optical depth to reionization through a measurement of the polarized cosmic microwave background (CMB) on the largest angular scales. The frequencies of the four CLASS telescopes, one at 38 GHz, two at 93 GHz, and one dichroic system at 145/217 GHz, are chosen to avoid spectral regions of high Atmospheric Emission and span the minimum of the polarized Galactic foregrounds: synchrotron Emission at lower frequencies and dust Emission at higher frequencies. Low-noise transition edge sensor detectors and a rapid front-end polarization modulator provide a unique combination of high sensitivity, stability, and control of systematics. The CLASS site, at 5200 m in the Chilean Atacama desert, allows for daily mapping of up to 70% of the sky and enables the characterization of CMB polarization at the largest angular scales. Using this combination of a broad frequency range, large sky coverage, control over systematics, and high sensitivity, CLASS will observe the reionization and recombination peaks of the CMB E- and B-mode power spectra. CLASS will make a cosmic variance limited measurement of the optical depth to reionization and will measure or place upper limits on the tensor-to-scalar ratio, r, down to a level of 0.01 (95% C.L.).
Junrui Zhou - One of the best experts on this subject based on the ideXlab platform.
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Atmospheric Emission inventory of hazardous air pollutants from china s cement plants temporal trends spatial variation characteristics and scenario projections
Atmospheric Environment, 2016Co-Authors: Shenbing Hua, He-zhong Tian, Chuanyong Zhu, Jiajia Gao, Kun Wang, Yifeng Xue, Yong Wang, Shiheng Duan, Junrui ZhouAbstract:Abstracts A multiple-year comprehensive Emission inventory of typical hazardous air pollutants (HAPs) from China's cement industry for the period 1980–2012, has been established by using technology-based dynamic Emission factors and detailed annual plant-specific cement production from different types of kilns. Our results show that the total Emissions of various HAPs (SO 2 , NO X , CO, PM, Hg, Cd, Cr, Pb, Zn, As, Ni and Cu) have rapidly increased by about 1–21 times at an annual average growth rate of 1–10% over the past three decades. Remarkably uneven spatial allocation features of these pollutants among provinces are observed. HAPs Emissions are primarily concentrated in the eastern and coastal provinces due to the concentration of cement plants and their huge volume of coal consumption. We predict the future Emission trends of HAPs through 2050 based on industry construction and policy guidance, and our scenario analysis indicates that HAPs Emissions will drop substantially because of the combined effects of cement production yields reduction and the increasing application rate of various air pollution control devices. The study suggests that highlighted attention should be paid to this energy-intensive industry to ensure stricter Emission standards are implemented for these HAPs Emissions in the future.
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Atmospheric Emission inventory of hazardous trace elements from china s coal fired power plants temporal trends and spatial variation characteristics
Environmental Science & Technology, 2014Co-Authors: He-zhong Tian, Junrui Zhou, Long Lu, Kun WangAbstract:Coal-fired power plants are the important sources of anthropogenic Atmospheric releases of various hazardous trace elements (HTE) because a large quantity of Emissions can cause wide dispersion and possible long-distance transportation. To obtain the temporal trends and spatial variation characteristics of various HTE discharged from coal-fired power plants of China, a multiple-year comprehensive Emission inventory of HTE including Hg, As, Se, Pb, Cd, Cr, Ni, and Sb has been established for the period 2000–2010. Thanks to the cobenefit removal effects of conventional particulate matter/sulfur dioxide/nitrogen oxides (PM/SO2/NOx) control devices, Emissions of these 8 toxic elements have shown a gradual decline since the peak in 2006. The total Emissions of Hg, As, Se, Pb, Cd, Cr, Ni, and Sb are substantial and are estimated at about 118.54, 335.45, 459.4, 705.45, 13.34, 505.03, 446.42, and 82.33 tons (t), respectively, in 2010. Shandong, Jiangsu, Shanxi, and Hebei always rank among the top ten provinces wi...
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Atmospheric Emission inventory of hazardous trace elements from China's coal-fired power plants-temporal trends and spatial variation characteristics
Environmental Science and Technology, 2014Co-Authors: He-zhong Tian, Kaiyun Liu, Junrui Zhou, Ji-ming Hao, Peipei Qiu, Chuanyong Zhu, Long Lu, Jiajia Gao, Kun Wang, Shenbing HuaAbstract:Coal-fired power plants are the important sources of anthropogenic Atmospheric releases of various hazardous trace elements (HTE) because a large quantity of Emissions can cause wide dispersion and possible long-distance transportation. To obtain the temporal trends and spatial variation characteristics of various HTE discharged from coal-fired power plants of China, a multiple-year comprehensive Emission inventory of HTE including Hg, As, Se, Pb, Cd, Cr, Ni, and Sb has been established for the period 2000?2010. Thanks to the cobenefit removal effects of conventional particulate matter/sulfur dioxide/nitrogen oxides (PM/SO2/NOx) control devices, Emissions of these 8 toxic elements have shown a gradual decline since the peak in 2006. The total Emissions of Hg, As, Se, Pb, Cd, Cr, Ni, and Sb are substantial and are estimated at about 118.54, 335.45, 459.4, 705.45, 13.34, 505.03, 446.42, and 82.33 tons (t), respectively, in 2010. Shandong, Jiangsu, Shanxi, and Hebei always rank among the top ten provinces with the highest Emissions. Further, future Emissions for 2015 and 2020 are projected with scenario analysis. Advanced technologies and integrated management strategies to control HTE are in great need.