Nitrated monoaromatic hydrocarbons (nitrophenols,nitrocatechols, nitrosalicylic acids) in ambient air: levels,mass size distributions and inhalation bioaccessibility

Environmental Science and Pollution Research - Nitrated monoaromatic hydrocarbons (NMAHs) are ubiquitous in the environment and an important part of atmospheric humic-like substances (HULIS) and...     

Plant growth regulators and EDTA improve phytoremediation potential and antioxidant response of Dysphania ambrosioides (L.) Mosyakin & Clemants in a Cd-spiked soil

Environmental Science and Pollution Research - Soil pollution due to potentially toxic elements is a worldwide challenge for health and food security. Chelate-assisted phytoextraction along with...     

Measurements,Theories and Simulations of Particle Deposits on Super-Heater Tubes in a CFB Biomass Boiler

The present investigation involves theories, simulations and experiments on deposit layers on super-heater tubes in a circulating fluidised bed in Västerås in Sweden. Simulation of particle trajectories in the vicinity of two super-heater tubes is conducted in a Eulerian-Lagrangian mode for the flue gas and the ash particles from the combustion process. Particle impingements on the tubes are investigated for different particle sizes. Measurements of the buildup of deposit layers in the super-heater environment are conducted using a deposit probe. Deposit layer growth and growth rate is analysed for different probe temperatures, as well as the aspect of sintering on the probe ring surface. Analysis of the probe deposit material and deposits from the super-heaters and from textile filters are chemically analysed. The temperature dependence of the deposit materials viscosity is predicted from the chemical analysis of the samples. A model is included to simulate the effect of the deposit layer thickness on the tube heat exchange. The results from the particle trajectory simulations show that particle larger than 10 mm will mainly impinge on the front of the first tube and that smaller particles are more dispersed due to turbulence and thermophorectic forces, enabling a more even impingement on the whole surface of the tubes. The probe deposit layer growth measurements show significant temperature dependence. The deposit material sintering and distribution is proven to be dependent on; temperature, particle size and exposure time. The stickiness of the deposit material is shown to be dependent on the SiO₂ and alkali relation in the samples, estimated through a viscosity model.     

电偶极辐射场的另一种计算方法

研究电偶极辐射问题的出发点是推迟势公式,本文先用格林函数法求解达朗贝尔方程组,得出推迟势公式;再用特殊函数理论对推迟势公式作展开,得出电偶极辐射场,并对远场和近场分别进行讨论。这种计算方法既能对电偶极辐射问题有一个较全面而且准确的认识,又能将数学思想与物理理论相结合,做到学以自用,融会贯通。     

Construction waste management based on industrial management models: a Swedish case study.

This paper describes a methodology for estimating the true internal costs of construction waste, aimed at promoting environmentally friendly waste management. The study employs cost-benefit analysis, contribution margin analysis, the polluter-pays principle and a mathematical model: the model for Efficient Use of Resources for Optimal Production Economy (EUROPE), which has been introduced previously by the author for assigning industrial costs to waste. The calculations are performed on construction waste created in a case study of a building project. Moreover, waste is regarded as, in a business sense, having the same basic status as any normal industrial product, namely the 'equality principle'. Application of the methodology is suggested to create incentives for environmental and profitability improvement in construction companies and other types of industrial sectors. The results of the case study show the generation of construction waste to substantially decrease the final operating income, due to the internal shadow price cost it creates. This paper is intended to reduce the gap between the choice of waste management procedures and their economic impact, the overall objective being to accomplish an improved industrial environmental situation.     

Measurement method for objective cyclist behavior parameters

Abstract

Objective: The objective of this research is to study the feasibility of measuring behavioral indicators that reflect effects of infrastructure and interaction with other road users.

Methods: An observation study was performed using 6 cameras above a separated cycle path next to a road which included a crossing with both cyclists and cars. A learning method based on Single Shot MultiBox Detector was applied to automatically detect the cyclists, and cyclist tracks were determined. Next, kinematic parameters were calculated from the cyclists’ tracks. Amongst others, the cyclists’ intensity, speed, position on the cycle path, and the distance to each other were analyzed for a busy period as well as for a quiet period of the day.

Results: With the measurement method developed in this study it is possible to analyze the cyclists’ intensity, the space they use at the cycle path, their average velocity, waiting times, the space and velocity amongst each other, and red light negation. However, collisions were not seen in the dataset analyzed, and the data is not sufficiently accurate to analyze sudden braking actions.

Conclusion: It can be concluded that the developed measurement method provides insight of the cyclists’ behavior in such a way that it can already be used for obtaining information to make changes to the infrastructure that will improve the comfort and safety of cyclists. The method could be further developed for doing qualitative comfort and safety analyses, and for doing analyses of the interaction between various types of road participants.