Top PDF Particle hygroscopicity and its link to chemical composition in the urban atmosphere of Beijing, China, during summertime

Particle hygroscopicity and its link to chemical composition in the urban atmosphere of Beijing, China, during summertime

Particle hygroscopicity and its link to chemical composition in the urban atmosphere of Beijing, China, during summertime

Another key product of AMS measurements is the oxi- dation level and chemical information of organic aerosols. Compared to inorganic species, which exhibit a well- characterized hygroscopic behavior, knowledge on the in- fluence of the water uptake of the organic aerosols remains limited (Kanakidou et al., 2005; Hallquist et al., 2009). The hygroscopicity of organic material varies with its oxidation state (Jimenez et al., 2009), which may be highly variable in the real atmosphere, depending on the history of an air mass. Such variation may present a significant challenge when predicting hygroscopicity, assuming a constant hygro- scopic growth factor of the organic aerosol fraction at a given relative humidity, as has usually been done in closure studies. More recently, some studies have been performed to inves- tigate the relationship between particle hygroscopicity and chemical composition in both field measurements and labo- ratory experiments (Massoli et al., 2010; Wong et al., 2011; Lambe et al., 2011; Rickards et al., 2013; Moore et al., 2012a, b; Suda et al., 2014; Paramonov et al., 2013; Levin et al., 2012). These works specially focused on parametriz- ing the empirical correlations between the atomic oxy- gen : carbon (O : C) ratio and organic hygroscopicity pa- rameter (κ) derived from either hygroscopic growth factor (e.g., Wu et al., 2013; Rickards et al., 2013) or cloud conden- sation nuclei (CCN) activity (e.g., Mei et al., 2013; Wong et al., 2011; Lambe et al., 2011; Chang et al., 2010). Typically, a linear parametrization of the correlation between κ and O:C was presented. Rickards et al. (2013) recently summarized the literature data and pointed out that the systematic vari- ability in parametrizations between organic κ and the O : C ratio determined from the different studies remains large. A recent work done by Suda et al. (2014) tested the influence of the number and location of molecular functional groups on the hygroscopicity of organic aerosols and may improve our understanding the mechanisms of the hygroscopicity of organics.
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Chemical composition, sources, and processes of urban aerosols during summertime in Northwest China: insights from High Resolution Aerosol Mass Spectrometry

Chemical composition, sources, and processes of urban aerosols during summertime in Northwest China: insights from High Resolution Aerosol Mass Spectrometry

(LZU site). The Chengguan district is located in eastern Lanzhou, a densely popu- lated area occupied by government, commerce, culture, and residence structures with relatively few industrial facilities. Supporting meteorological and air quality data were obtained from the government monitor stations located in the same district. The date and time used in this paper are given as Beijing Time (BJT: UTC +8). Note that the

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Measurements of ozone and its precursors in Beijing during summertime: impact of urban plumes on ozone pollution in downwind rural areas

Measurements of ozone and its precursors in Beijing during summertime: impact of urban plumes on ozone pollution in downwind rural areas

Beijing has become more serious in recent years (Hao and Wang, 2005; Shao et al., 2006; Wang et al., 2006). For example, the ambient air quality standard for ozone has frequently been exceeded, with the peak hourly averaged concentration of 286 ppbv recorded (Wang et al., 2006). Beijing is the center of an urban agglomeration in North China. Compared to the other two city cluster regions in China, i.e., the Yangtze River

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Assessment Of NPK In Human Male And Female Urine For Its Fertilising Potential In Agriculture

Assessment Of NPK In Human Male And Female Urine For Its Fertilising Potential In Agriculture

discharge into water is reduced by about 60% irrespective of the type of treatment [10]. Pure urine is sterile but there is the likelihood of cross-contamination with the use of urine separating (Ecosan) toilets [28]. According to Jönsson et al. (2000) separated urine contains a greater part of the total nutrients in normal sewage; 80% of N, 55% of P, and 60% of K in just 1.5% of the volume of the sewage. According to Rheiberger (1936), there are comparable levels of creatine, urea and ammonia nitrogens in urine among primates such as man, mangabeys, baboons and chimpanzees. However, he identified sex differences in creatinine nitrogen coefficients of the male mangabeys, baboons and chimpanzees to be higher than those in the female counterparts. In small cases there was reversal of the magnitude seen in the macaques species precluding an assumption as to the validity of the observation. In analysing sex differences in urine with respect to lysine and α - amino nitrogen, the mean excretion of α - amino nitrogen whether ―total,‖ ―free,‖ or ―bound,‖ was higher for females than for males [22]. Thus, it is possible that the higher rate of amino acid excretion observed in females might be correlated with the sexual cycle, although no evidence of this was observed in the case of the four amino acids studied by Thompson and Kirby (1949) when samples from the same subjects were taken at various stages of the menstrual cycle. The influence of sex (gender) on the level of NPK in human urine has received no attention. Therefore, there is a need to study the effect from the Ecological Sanitation (ECOSAN) perspective, especially under local conditions. This is because gender ECOSAN urinals are going to spring up with the advent of industries and ECOSAN concepts, especially in the developing countries. The use of urine in agriculture has been studied in countries such as Sweden, Germany, Switzerland, South Africa, Burkina Faso and Nigeria. In all these studies, the fertilizing ability of human urine was established as being comparable to that of chemical fertilizers, such as 21% N ammonia. However, in Ghana little U
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Utilization of Electronic Waste Plastic in Concrete

Utilization of Electronic Waste Plastic in Concrete

All over the world, the quantity of electrical and electronic waste generated each year, especially computers and televisions, has assumed alarming proportions. In 2006, the International Association of Electronics Recyclers (IAER) 8 projected that 3 billion electronic and electrical appliances would become WEEE (Waste Electrical and Electronic Equipment) or e-waste by 2010. That would tantamount to an average e-waste generation rate of 400 million units a year till 2010. Globally, about 20- 50 MT (million tons) of e-wastes is disposed off each year, which accounts for 5% of all municipal solid waste. Although no definite official data exist on how much waste is generated in India or how much is disposed of, there are estimations based on independent studies conducted by the NGOs or government agencies. According to the Comptroller and Auditor- General‟s (CAG) report, over 7.2 MT of industrial hazardous waste, 4 lakh tones of electronic waste, 1.5 MT of plastic waste, 1.7 MT of medical
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The Impact of E-Commerce Securi ty, and National Environment  on Consumer adoption of Intern et Banking in Malaysia and  Singapore

The Impact of E-Commerce Securi ty, and National Environment on Consumer adoption of Intern et Banking in Malaysia and Singapore

views an innovation as offering an advantage over previous ways of performing the same task (Roger, 1983; Agarwal & Prasad, 1997). Internet experience and banking need is defined as the degree to which an innovation is viewed as being consistent with the existing values, needs and experiences of a user (Rogers, 1983; Taylor & Todd, 1995). Trialability is the extent to which users would like an opportunity to experiment with an innovation prior to committing to its usage (Roger, 1983; Agarwal & Prasad, 1997). Subjective norm refers to a person’s perception that most people who are important to him or her think he or she should or should not perform the behavior in question (Fishbein & Ajzen, 1975; Tan & Teo, 2000). Self-efficacy is defined as an individual’s self-confidence in his or her ability to perform a behavior (Bandura, 1982; Taylor & Todd, 1995). While, facilitating condition refers to the easy access of technological resources and infrastructure. Government support is consistent with the national systems of innovation theory that posits that government policies may encourage or mandate technology development and adoption (King et. al., 1994; Wolcott et. al., 2001).
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Selection of the temperature of casting the bronzes to plaster moulds

Selection of the temperature of casting the bronzes to plaster moulds

dependence from the temperature of casting the bronze to the mould on Figure 6. From the introduced cross - section of casts from the probe TDAg, it results that it together with considerably grows up the depth of the contraction cavity with the growth of the temperature of casting, and what joins with this executed along its axis the volumetric contraction grows up, especially bronze B555 (Fig. 5a and 6). The bronze B10 is characterizes considerably smaller volumetric contraction (Fig. 5b and 6), however overheated 1180 °C above and cast to the hot plaster mould, in the conditions of the atmospheric pressure, it undergoes strong gassing with what considerable decrease of the depth of the contraction cavity joins (Fig. 5b 1200 ° C and Fig . 6). Zinc as high active metal in the relation of oxygen influences the lower- ing of the content of gases dissolved in the bronze B555. Consid- erably larger content Zn in the chemical composition of the bronze B555 (approx. 5%), in the comparison with the bronze B10 (to 0.5 %), it favours creation on the surface of the solidifica- tion bronze of the layer of oxides Zn and Cu, in the composition natural slags about the smaller mass density from the liquid bronze, making difficult chemical adsorption and dissolving the hydrogen and oxygen in the liquid bronze. Bronze B10 including first of all the admixture approx. 10% Sn, element of little active in the relation to oxygen, it absorbs from surroundings highly both the hydrogen as and the oxygen, what it brings in the conse- quence, together with the growth of the temperature of casting, to gassing the bronze.
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Rare earth elements, U and Th in tunnel dusts of São Paulo city, Brazil

Rare earth elements, U and Th in tunnel dusts of São Paulo city, Brazil

en for the certified reference materials basalt BE-N and granite GS-N (SARM). All sub-samples and reference materials were, then, irradiated for 8 h at a thermal neutron flux of, approximately, 5 10 12 n cm -2 s -1 , at the IEA-R1 nuclear research reactor, located at IPEN. The measurements of the induced gamma radiation were done in a gamma spectrometry system, which included a high purity germanium gamma ray detector (Canberra GX20190) and associated electronics. Each sample was measured twice: the first measure occurred 7 to 8 days after the irradiation and, the second one, 7 to 10 days after the first measurement. The quality control of the results was made by the analysis of certified reference material Soil-7 (IAEA), and the results showed relative errors lesser than 10% regarding the certified values.
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Criterion for selection the optimal physical and chemical properties of cobalt aluminate powder used in investment casting process

Criterion for selection the optimal physical and chemical properties of cobalt aluminate powder used in investment casting process

The effect of modification of the surface layer of the castings made from superalloys: Inconel 713C, René 77 and MAR-M 509 was investigated on the cross sections of the castings. The reduction of grain size of invested alloys after modification was obtained independently from the kind of used cobalt aluminate (Fig. 6.). The measurements of the average surface area of grain cross section of γ matrix in the cross section of casting revealed the differences in the size of grains up to the type of modifier. From Figure 6 one can see that the most coarse grain structure characterize the nonmodified castings. The finest macrostructure characterizes the samples which were modified by 5% of Mason Color and Remet powders with higher contamination of cobalt: 39.43%, 34.79
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SOCIAL ECONOMY – A FORM OF INCLUSION AND OF ''REACTIVATING'' OF LABOR IN THE CONTEXT OF THE CURRENT CRISIS

SOCIAL ECONOMY – A FORM OF INCLUSION AND OF ''REACTIVATING'' OF LABOR IN THE CONTEXT OF THE CURRENT CRISIS

)n the context of the cohesion policy, solidarity must represent a support for development . For that purpose, solidarity can be seen as a help for self‐help and its success depends a great deal on the capacity and the training of the people to whom the support of making maximum profit out of these addresses to. This support does not mean exclusively financial support, although it is necessary and important but, of all things, it means an exchange of experiences and cooperation, the development of capacity through training, open discussions with the interested factors and last but not least a critic, but a constructive dialogue between the various levels of government: European, national, regional, local. )n other words, a functional labor market should represent a catalyst for the general objective of the European Union – social and economical cohesion – because it has in view the connections with the different markets of the services and of the goods and generates the necessary income for supporting the participation of the individuals, bringing them together, placing them in collaborations. )n this context, the starting points for promoting the inclusion through the activities of social economy have in view: adapting the institutional environment, developing the public‐private partnership, developing the social dialogue between players, investments in the human capital and supporting the exchange of good practices within the European Union.
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Aerosol composition and sources during the Chinese Spring Festival: fireworks, secondary aerosol, and holiday effects

Aerosol composition and sources during the Chinese Spring Festival: fireworks, secondary aerosol, and holiday effects

Figure 1. Time series of meteorological parameters (a) relative humidity (RH) and temperature (T ); (b) wind direction (WD) and wind speed (WS) at the height of 100 m; mass concentrations of (c) PM 2.5 and NR-PM 1 + BC and (d) submicron aerosol species. Also shown in (a) and (b) is the temperature and wind speed at the height of 8 m which are in blue. The extinction coefficient (b ext ) at 630 nm is shown in (c). Three events, i.e., Lunar New Year (LNY), Lunar Fifth Day (LFD) and Lantern Festival (LF) with significant influences of fireworks are marked in (c). In addition, the classified clean periods (CPs) and polluted events (PEs) are marked as shaded gray and pink areas, respectively.
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Morphological, chemical and optical absorbing characterization of aerosols in the urban atmosphere of Valladolid

Morphological, chemical and optical absorbing characterization of aerosols in the urban atmosphere of Valladolid

There is a complete lack of information about absorption and scattering coefficients in the atmosphere of Valladolid (nei- ther any other towns from center Spain) and its environment is not comparable to other towns in central Europe because the combination of the aridity and the agricultural usage of the land result in aerosol masses that are high compared to other European cities of similar size and population. This is also true for all of central Spain. The absorption coefficients were measured only for particles with aerodynamic diame- ters <1 µm. Larger particles may potentially contribute to the the overall atmospheric absorption coefficient; however, as discussed in the previous section, the majority of carbona- ceous material was found at sizes smaller than 1 µm. Since elemental carbon is the most predominant light absorber in the atmosphere, the measurements of absorption coefficient that we present here are probably good estimates of the total absorption coefficient.
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Biomass-burning impact on CCN number, hygroscopicity and cloud formation  during summertime in the eastern Mediterranean

Biomass-burning impact on CCN number, hygroscopicity and cloud formation during summertime in the eastern Mediterranean

Towards understanding the impacts of the observed BB on clouds, we study the behavior of cloud droplet forma- tion for typical boundary layer conditions. For this, we ap- ply a state-of-the-art cloud droplet formation parameteriza- tion to the observations, assuming typical values of updraft velocity for marine boundary layer clouds. We find that the very high concentrations of CCN during the influence of BB events tend to promote the competition for cloud wa- ter vapor and substantially depress the cloud supersatura- tion down to very low levels (even as low as 0.06 %). As a result, only the largest particles, from 110–150 nm in di- ameter and above, can activate to form cloud droplets. This also means that droplet number becomes highly insensitive to changes in aerosol in the presence of BB; indeed clouds influenced by BB exhibit a relative decrease in maximum supersaturation by 12 %, while at the same time, BB aug- ments the potential droplet number by 8.5 %. These results also support the chemical dispersion/mixing state analysis of the CCN data, as only the largest aerosol sizes sampled activate and are exposed to cloud processing. Based on the average sensitivity of droplet number to changes in aerosol number and composition, and observed variances thereof, we attribute the relative contribution of chemical composi- tion and total aerosol number to the variance of droplet num- ber. We find that the distance from the source is a key pa- rameter that governs the importance of each parameter, with the influence of the chemical composition becoming increas- ingly important (controlling up to 25 % of the droplet num- ber variability) with growing distance from the source. Close
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Chemical characterization of submicron aerosol and particle growth events at a national background site (3295 m a.s.l.) on the Tibetan Plateau

Chemical characterization of submicron aerosol and particle growth events at a national background site (3295 m a.s.l.) on the Tibetan Plateau

The Tibetan Plateau (∼ 2 000 000 km 2 ) is the highest plateau in the world, with an average altitude of over 4000 m a.s.l. The Tibetan Plateau is an ideal location for char- acterizing rural and regional background aerosol due to mi- nor influences of anthropogenic activities. However, chemi- cal characterization of aerosol particles in the Tibetan Plateau is rather limited, and therefore their sources, properties and evolution processes are poorly known. Cong et al. (2015) reported the seasonal variations of various aerosol com- ponents, including carbonaceous species and water-soluble ionic species on the south edge of the Tibetan Plateau. Sul- fate was found to dominate the total ionic mass (25 %), fol- lowed by nitrate. In addition, most aerosol species showed pronounced season variations in the pre-monsoon period due to biomass burning impacts from India and Nepal. Zhao et al. (2013) also characterized the chemical composition and sources of total suspended particulate (TSP) at Lulang on the southeastern TP, based on 1 year of measurements. Similar seasonal variations with higher concentrations dur- ing the pre-monsoon period were observed. The back tra- jectory analysis showed evident transport of air pollutants from south Asia to the TP. The analysis of size-segregated aerosol samples collected at a remote site in the inland of the Tibetan Plateau during 2012 further confirmed the high concentrations of organic carbon (OC) and elemental carbon (EC) during the pre-monsoon period (Wan et al., 2015), al- though their concentrations in PM 1 (2.38 and 0.08 µg m −3 ,
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An Advancement To The Security Level Through Galois Field In The Existing Password Based Technique Of Hiding Classified Information In Images

An Advancement To The Security Level Through Galois Field In The Existing Password Based Technique Of Hiding Classified Information In Images

Let „S‟ be the password of length „T‟ characters. The password could be of any length and any combination of characters like lower case letters, upper case letters, and special characters. The choice of password doesn‟t affect the performance of the algorithm. It is used to enhance the security of the algorithm by one more level. This password is converted into a binary code and is used for storing one of the bits of the 2BC. It is repeated until all bits are embedded. Let E (i, j) be another randomly selected pixel from the cover image. The lower nibble of E will be used to hide the 2BC‟s obtained from the matching positions of M, in different positions as shown in Fig. 2 based on a password. If the password bit is „0‟, then the first bit of 2BC is saved in position 1, else it is saved in position 2. The second bit of 2BC can be saved using the technique described below. Save the second bit in a specific order. For example, the first 10 bits are hidden in position 1 or 2, whichever, is available after embedding the first bit of the 2BC, the next five bits are hidden in position 3 and next bit is hidden in position 4. Repeat the same pattern until all bits are embedded. By using this approach, the PSNR value can be controlled to some degree.
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The Existence Of Leading Islands Securing And The Border Areas Unitary State Of Indonesia An Analysis In Law Perspective

The Existence Of Leading Islands Securing And The Border Areas Unitary State Of Indonesia An Analysis In Law Perspective

Abstract: The research was carried with the aim to discover the existence of securing the foremost islands and state border region of the Republic of Indonesia reviewed from a legal perspective, which is directly related to the existence of security and dispute resolution methods as well as the governance of the foremost islands and border region in Kalimantan which bordering Malaysia. This study was conducted in Nunukan district and the surrounding provinces of Kalimantan, in this research method that used is normative legal analysis data with juridical and qualitative descriptive approach. The results showed that the security of foremost islands and border region of law perspective in accordance with the Law No. 34 of 2004 regarding the Indonesian National Army has not been implemented to the fullest to realize the security of foremost islands and border region as the frontline of the Republic of Indonesia. The existence of leading islands securing and the border region of the Republic of Indonesia still contain many weaknesses in terms of both governance and security.
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The chemical composition of the snow  in urban environment in the Far North

The chemical composition of the snow in urban environment in the Far North

Наиболее высокие значения Кс изучаемых металлов характерны для снегового покрова (в твердой фазе) сквера и улиц г.. Мурманск максимальные коэффициенты концентрации Ni и Cu получены т[r]

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The comparison of the structure and microhardness of the tool steel C90 and HS 6-5-2 remelted with the electric arc

The comparison of the structure and microhardness of the tool steel C90 and HS 6-5-2 remelted with the electric arc

The samples were remelted on the surface with the electric arc with the use of the FALTIG 315AC/DC apparatus. The single remelting was applied. The treatment parameters were used: amperage of the electric arc I = 100 A, speed of the electrode movement v=200 mm/min. As the plasma formative gas, the argon was used. The treatment has been conducted at the depart- ment of Foundry and Welding of Rzeszow University of Tech- nology. After the remelting, there has been the conventional tempering done 1x1 hour in a temperature of 200°C for the steel C90 and 2x2 hours in the temperature of 560 °C for the steel HS 6- 5-2. Parameters of tempering (temperature, time and multiplicity) of the tested steels were selected according to the standard PN-EN ISO 4957:2002U. The microhardeness measurements were made with the Hanemanna objective mph 100. The load used was 0,064 N, the operating time of the load was 10 s. Metallographic tests were conducted on the optical microscope - Neophot 2 and Tesla BS-340 electronic scanning microscope.
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Gaseous pollutants in Beijing urban area during the heating period 2007–2008: variability, sources, meteorological, and chemical impacts

Gaseous pollutants in Beijing urban area during the heating period 2007–2008: variability, sources, meteorological, and chemical impacts

height of 10 m above the ground level. The 24-h back- ward trajectories were calculated for four time points (00:00, 06:00, 12:00, 18:00 UTC) per day for the observation period. The individual trajectories were grouped into 7 clusters using the clustering tool included in HYSLPIT4.8. Figure 8 shows the mean trajectories for the 7 clusters and their ratios to the total number of trajectories. Observed trace gas concentra- tions are associated with the trajectories and then grouped according to the trajectory clusters, and finally statistics for each group of data are listed in Table 4. Clusters 1, 2, and 7 represent relatively low and slow-moving air parcels con- taining high SO 2 , CO, and NO y concentrations, low O 3 con-
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Population exposure to PM2.5 in the urban area of Beijing.

Population exposure to PM2.5 in the urban area of Beijing.

Based on a hotspot analysis, we can develop statistics regarding populations under continuous exposure. Previous studies used census geographic units as the smallest population exposure unit, but such a unit often has a different risk exposure level. To solve this problem, the area-weighting method was used to calculate the population under exposure. This method involves a straightfor- ward algorithm for areal interpolation. Based on the assumption that population is evenly distributed within a source zone, the constant population density of each zone is initially estimated. Then, the size of each overlapping area between target and source Figure 6. Number of cumulative exceedance days.
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