Ozone sensitivity factor: NOX or NMHCs?: A case study over an urban site in Delhi, India

Abstract. High contribution of secondary organic aerosol to the loading of fine particle pollution in China highlights the roles of volatile organic compounds oxidation. Therein, particulate active metallic oxides in dust, like TiO2 and Fe ions, were proposed to influence the photochemical reactions of ambient VOCs. A case study was conducted at an urban site within Xi'an, northwestern China, to investigate the origin and transformation of VOCs during a windblown dust-to-haze pollution episode, and the assumption that dust would enhance the oxidation of VOCs was verified. Local vehicle exhaust (24.76 %) and biomass burning (18.37 %) were found to be the two largest contributors to ambient VOCs. In the dust pollution period, sharp decrease of VOCs loading and aging of their components were observed. Simultaneously, the secondary oxygenated VOCs fraction (i.e., methylglyoxal) increased. Source strength, physical dispersion, and regional transport were eliminated from the major factor for the variation of ambient VOCs. In another aspect, about 2 and 3 times increase of the loading of Iron (Fe) and titanium (Ti) was found in the airborne particle, together with fast decrease of trans-/cis-2-butene ratios which demonstrated that dust can accelerate the oxidation of ambient VOCs and formation of SOA precursors.

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Distribution and variability of total mercury in snow cover—a case study from a semi-urban site in Poznań, Poland

Environmental Science and Pollution Research ◽

10.1007/s11356-016-7627-8 ◽

2016 ◽

Vol 23 (23) ◽

pp. 24316-24326 ◽

Cited By ~ 4

Author(s):

Patrycja Siudek

Keyword(s):

Snow Cover ◽

Total Mercury ◽

Urban Site

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Elemental composition of PM0.25 collected in an urban site of Argentina: A first case study

Spectrochimica Acta Part B Atomic Spectroscopy ◽

10.1016/j.sab.2019.105712 ◽

2019 ◽

Vol 161 ◽

pp. 105712 ◽

Cited By ~ 1

Author(s):

Bethania L. Lanzaco ◽

María Laura López ◽

Luis E. Olcese ◽

Beatriz M. Toselli

Keyword(s):

Elemental Composition ◽

Urban Site ◽

First Case

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Application of simulation technique on debris flow hazard zone delineation: a case study in the Daniao tribe, Eastern Taiwan

Natural Hazards and Earth System Science ◽

10.5194/nhess-11-3053-2011 ◽

2011 ◽

Vol 11 (11) ◽

pp. 3053-3062 ◽

Cited By ~ 22

Author(s):

M. P. Tsai ◽

Y. C. Hsu ◽

H. C. Li ◽

H. M. Shu ◽

K. F. Liu

Keyword(s):

Debris Flow ◽

Debris Flows ◽

Large Scale ◽

Sensitivity Factor ◽

Original Design ◽

Initial Volume ◽

Front Position ◽

Landslides And Debris Flows ◽

Numerical Program

Abstract. Typhoon Morakot struck Taiwan in August 2009 and induced considerable disasters, including large-scale landslides and debris flows. One of these debris flows was experienced by the Daniao tribe in Taitung, Eastern Taiwan. The volume was in excess of 500 000 m3, which was substantially larger than the original design mitigation capacity. This study considered large-scale debris flow simulations in various volumes at the same area by using the DEBRIS-2D numerical program. The program uses the generalized Julien and Lan (1991) rheological model to simulate debris flows. In this paper, the sensitivity factor considered on the debris flow spreading is the amount of the debris flow initial volume. These simulated results in various amounts of debris flow initial volume demonstrated that maximal depths of debris flows were almost deposited in the same area, and also revealed that a 20% variation in estimating the amount of total volume at this particular site results in a 2.75% variation on the final front position. Because of the limited watershed terrain, the hazard zones of debris flows were not expanded. Therefore, the amount of the debris flow initial volume was not sensitive.

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Urban Site Development as Temporal Carbon Storage—A Case Study in Germany

Sustainability ◽

10.3390/su12145827 ◽

2020 ◽

Vol 12 (14) ◽

pp. 5827

Author(s):

Annette Hafner ◽

Simon Slabik ◽

Michael Storck

Keyword(s):

Life Cycle ◽

Carbon Storage ◽

Energy Demand ◽

High Standard ◽

Urban Site ◽

Low Carbon ◽

Building Site ◽

The Sustainable Development ◽

Lca Results

Increasing the use of sustainably sourced wood in construction for temporal carbon storage could be one vital part in the transition towards reaching the sustainable development goals for climate action and sustainable cities and communities. This paper explains the detailed steps from the planning to the realization process and shows how building with wood could be linked to the entire process from the sales of building plots to the realization of projects. Additionally, based on EN 15978, life cycle assessment (LCA) results of the constructed buildings were conducted to calculate the realistic carbon storage and the global warming potential for all new erected buildings on the site. The case study area and living lab is a building site in Munich with 566 flats, which will be finished in 2020 and will be the largest urban timber neighborhood in Germany by then. All development activities are summarized under the concept of building an eco-city with low carbon emissions and a high standard for living for all groups of inhabitants. Eight buildings with different material selections ranging from wood-constructions to wood-concrete hybrid constructions and concrete constructions with different energy standards are environmentally assessed. Results show that about 12.5 million kg of CO2 are stored in the wooden structures over the estimated life cycle of 50 years within this neighborhood. This clearly demonstrates the potential that building with wood has for achieving climate targets. Further results show that heating energy demand and material choices have a significant influence on LCA results.

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