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Abstract: Linear and nonlinear magnetic susceptibilities of a LaCoO3 particle sample were measured to shed light on the surface ferromagnetism of LaCoO3. The ferromagnetic transition temperature T C estimated from the nonlinear magnetic susceptibility agrees well with that inferred from Kouvel–Fisher''s analysis of the linear susceptibility, while the critical exponent γ deduced simultaneously from the same analysis is incompatible with any values reported for 2d and 3d ferromagnetism. The results are discussed in view of surface and/or size effects in detail. [Copyright &y& Elsevier]

The low temperature (4) magnetic properties of chromium(III) oxide particles have been studied. A clear evidence of the presence of weak ferromagnetism is observed below 250 K. The magnetisation curves as a function of the applied field show coercive fields due to the canted antiferromagnetism of the particles. Around 55 K a maximum is observed in the zero-field-cooled curves; this maximum can be assumed as a blocking temperature, similarly to ultrafine ferromagnetic particles. [Copyright &y& Elsevier]

Magnetization curves of Co0.35(SiO2)0.65 granular film were measured from 70 up to 390 K. Although the anhysteretic magnetization loops could be well described using an integral of Langevin functions weighted by a distribution function of moments, the fitting parameters show an anomalous behavior. The median magnetic moments exhibit a low-temperature limit close to zero, and all have values well below the value expected from TEM analyses, with observed differences up to 82%. [Copyright &y& Elsevier]

Many studies have been conducted focusing on the contribution of land emission sources to PM 2.5 in China; however, little attention had been paid to other contributions, especially the secondary contributions from shipping emissions to atmospheric PM 2.5 . In this study, a combined source apportionment approach, including principle component analysis (PCA) and WRF-CMAQ simulation, was applied to identify both primary and secondary contributions from ships to atmospheric PM 2.5 . An intensive PM 2.5 observation was conducted from April 2014 to January 2015 in Qinhuangdao, which was close to the largest energy output port of China. The chemical components analysis results showed that the primary component was the major contributor to PM 2.5 , with proportions of 48.3%, 48.9%, 55.1% and 55.4% in spring, summer, autumn and winter, respectively. The secondary component contributed higher fractions in summer (48.2%) and winter (36.8%), but had lower percentages in spring (30.1%) and autumn (32.7%). The hybrid source apportionment results indicated that the secondary contribution (SC) of shipping emissions to PM 2.5 could not be ignored. The annual average SC was 2.7%, which was comparable to the primary contribution (2.9%). The SC was higher in summer (5.3%), but lower in winter (1.1%). The primary contributions to atmospheric PM 2.5 were 3.0%, 2.5%, 3.4% and 2.7% in spring, summer, autumn and winter, respectively. As for the detailed chemical components, the contributions of shipping emissions were 2.3%, 0.5%, 0.1%, 1.0%, 1.7% and 0.1% to elements & sea salt, primary organic aerosol (POA), element carbon (EC), nitrate, sulfate and secondary organic carbon (SOA), respectively. The results of this study will further the understanding of the implications of shipping emissions in PM 2.5 pollution., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Particulate matter (PM) has been found to damage vital body organs, including the lungs and heart, through vascular damage and oxidative stress. Recently, renal function and chronic urologic diseases have also been found to be related to PM. To investigate this, we reviewed the characteristics of PM related to renal toxicity, including recent studies on the associations of urologic diseases with PM. PM can include constituents that cause renal toxicity, such as lead, cadmium, arsenic, and crystalline silica, which result in renal tubular or interstitial damage. Since 2008, 7 studies have evaluated the renal effects of PM. Two prospective cohort studies and a quantitative study of consecutive patients showed that PM may be related to decreased renal function, as shown by the estimated glomerular filtration rate of diseased or aged participants. Two cross-sectional studies found an association between PM and chronic kidney disease. One of those studies identified the specific renal diseases of immunoglobulin A nephropathy and membranous nephropathy. Two studies that analyzed renal cancer and PM showed no evidence that renal cancer is related to PM. Nine studies were evaluated regarding the relationship of bladder and prostate cancer with PM. The evidence for an association of PM with bladder and prostate cancer is still inconclusive. Although some recently published studies have shown a significant relationship, the causal relationship is not clear. Further well-designed studies on specific renal diseases are required.

This study systemically investigated the ambient PM 2.5 (n=108) with comprehensive analyses of the chemical composition, identification of the potential contributors, and estimation of the resultant respiratory physician visits in the residential regions near energy-consuming and high-polluting industries in central Taiwan. The positive matrix fraction (PMF) model with chemical profiles of trace metals, water-soluble ions, and organic/elemental carbons (OC/EC) was applied to quantify the potential sources of PM 2.5 . The influences of local sources were also explored using the conditional probability function (CPF). Associations between the daily PM 2.5 concentration and the risk of respiratory physician visits for the elderly (≥65years of age) were estimated using time-series analysis. A seasonal variation, with higher concentrations of PM 2.5 , metals (As, Cd, Sb, and Pb), OC/EC and ions (i.e., NO 3- , SO 4 2- and NH 4 + ) in the winter than in the spring and summer, was observed. Overall, an increase of 10μgm -3 in the same-day PM 2.5 was associated with an ~2% (95% CI: 1.5%-2.5%) increase in respiratory physician visits. Considering the health benefits of an effective reduction, we suggest that the emission from coal combustion (23.5%), iron ore and steel industry (17.1%), and non-ferrous metallurgy (14.4%), accounting for ~70% of the primary PM 2.5 in the winter are prioritized to control., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Increased ambient concentration of particulate matters are considered as one of major causes for increased prevalence or exacerbation of asthma or asthma like symptoms. Recently, possible temporal variation in risks of PM on mortality has been suggested. We investigated short-term effect of both PM 10 and PM 2.5 on asthma hospitalization, and assessed temporal variation of PM risks in Seoul, Korea, 2003-2011. Generalized additive model was used to estimate PM risks on asthma hospitalization with consideration by long-term trend, influenza epidemic, day of week, meteorological factors. To assess temporal variation of PM risks, year-round PM risks were estimated. Stratified analysis by season and age-group were also conducted. Estimated RRs of PM on asthma hospitalization by an increase of 10㎍/㎥were 1.0084 (95% CI: 1.0041-1.0127) and 1.0156 (95% CI: 1.0055-1.0259) respectively with 7-days lag periods (lag06). PM 2.5 had stronger effect than PM 10 for all age group. Elderly group was most affected by PM. For the analysis of temporal variation of PM risks, we found increasing trend in total population and the elderly group. In the season-specific analysis, we also found increasing trend in winter for PM 10 , and in spring for PM 2.5 . PM 10 and PM 2.5 has adverse effect on asthma hospitalization with evidence suggesting temporal variation in PM risks. Further research will be needed to confirm the temporal variation of PM risk on asthma hospitalization, and to identify casual factors affecting this temporal variation. This study results could be evidentiary materials for establishing valid public health policies to reduce health burden or economic burden of asthma., (Copyright © 2017. Published by Elsevier Inc.)

This study investigates PM 2.5 -bound PAHs for rural sites (Dacheng and Fangyuan) positioned close to heavy air-polluting industries in Changhua County, central Taiwan. A total of 113 PM 2.5 samples with 22 PAHs collected from 2014 to 2015 were analyzed, and Positive Matrix Factorization (PMF) and diagnostic ratios of PAHs were applied to quantify potential PAH sources. The influences of local and regional sources were also explored using the conditional probability function (CPF) and potential source contribution function (PSCF) with PMF-modeled results, respectively. Annual mean concentrations of total PAHs were 2.91 ± 1.34 and 3.04 ± 1.40 ng/m 3 for Dacheng and Fangyuan, respectively, and their corresponding BaP eq were measured at 0.534 ± 0.255 and 0.563 ± 0.273 ng/m 3 in concentration. Seasonal variations with higher PAHs found for the winter than for the spring and summer were observed for both sites. The lifetime excess cancer risk (ECR) from inhalation exposure to PAHs was recorded as 4.7 × 10 -5 overall. Potential sources of PM 2.5 -bound PAHs include unburned petroleum and traffic emissions (42%), steel industry and coal combustion (31%), and petroleum and oil burning (27%), and unburned petroleum and traffic emission could contribute the highest ECR (2.4 × 10 -5 ). The CPF results show that directional apportionment patterns were consistent with the actual locations of local PAH sources. The PSCF results indicate that mainly northeastern regions of China have contributed elevated PM 2.5 -bound PAHs from long-range transports., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Based on a dilution sampling system and domestic burning tests, emission factors (EFs) for eleven heavy metals of V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Sb and Pb in PM 2.5 from raw coal and honeycoal burning were calculated, using their contents in raw coals of different provinces. Then the total emission amounts of heavy metals from residential coals burning in 2012 were calculated and 30 km×30 km grid cell-based emission inventories were established. The results showed that the EFs of Pb, Zn, As and Cu were higher from honeycomb coal burning. They were 27.1, 16.8, 0.99 and 0.97 mg·kg -1 , which were 56, 6, 10 and 2 times of those for raw coal, respectively. The total emissions of V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Sb and Pb in PM 2.5 from residential coal burning in 2012 were 0.5, 30.1, 59.5, 1.1, 29.3, 20.0, 188.9, 64.9, 1.6, 3.4 and 176.7 t. Hunan, Hebei, Inner Mongolia, Henan, and Shandong held higher emission amounts, which were 12.4%, 12.3%, 10.4%, 9.9% and 9.3% of the total emissions of the whole country. Beijing, Henan, Shandong, Hunan, Jiangxi, Guizhou and Inner Mongolia were the regions with higher emission intensities and emission amounts per capita. The spatial distribution showed that the regions with higher annual emissions of Zn and Pb distributed widely, mainly in Inner Mongolia, Hebei, Beijing, Tianjin, Shandong, Henan, Gansu, Hunan and Jiangxi. The emission inventories for heavy metals in fine particles established here are important for regional air quality modeling and human health risk assessment.

Approach: Backwashing process was implemented using column of deep bed filter with different media characteristics to provide optimal operation condition. Minimum velocity of fluidization (Vmf) and porosity at minimum fluidization (emf) were investigated under different operation condition and grains size. The results were compared with Wen and Yu equation and Richardson-Zaki correlation, respectively. Backwashing model was developed to predict the effect of fluid shear strength (τa), velocity grade (G), dissipation rate coefficient (Ca), and parameters of random motion (Ca0:5/Re) on the energy dissipation rate during fluidization process. Results: The simulated result of proposed models gives a good convergence to observed data. It was seen that a smaller size of sand media need a lower value of backwash velocity than a higher size for lifting filter media. Fixed bed porosity increased from 0.510 to 0.704 at bigger size of sand media (1.18 mm), while it increased to 0.680 at smaller size of sand media (0.5 mm). The simulated result showed that Richardson-Zaki model has a good convergence with experimental result of expanded porosity for all effective size of sand media. Conclusion: It was concluded that low superficial velocity produced through the system at higher velocity grade (G). In addition to that the fluid shear strength (τa) increased along with expanded porosity. The maximum fluid shear strength (τa) was occurred at porosity equal to 0.730 and in large effective size of sand media (1.18 mm). Also, the lighter particles caused a high increasing rate in the random motion parameters compared with heavier particles. The study showed that the effluent suspended solid and hydrodynamics detachment of deposited fine particles reduces with time of fluidization but it rises with backwash discharge. The bigger grain of sand media has a lower peak point of optimum backwash time than smaller grain due to accumulation a large amount of deposit fine particles. The study was shown that the energy dissipation rate and the velocity grade have a dominant mechanism in filter backwashing and increases with increasing particle population in a expanded bed. The result revealed that the random motion parameter increased along with increasing in fraction solids and a higher rate was appeared in the lighter particles that it caused increasing in random motion parameter compared with heavier particles. [ABSTRACT FROM AUTHOR]

Excessive inter-contamination with heavy metals hampers the application of biological treatment products derived from mixed or mechanically-sorted municipal solid waste (MSW). In this study, we investigated fine particles of <2mm, which are small fractions in MSW but constitute a significant component of the total heavy metal content, using bulk detection techniques. A total of 17 individual fine particles were evaluated using synchrotron radiation-based micro-X-ray fluorescence and micro-X-ray diffraction. We also discussed the association, speciation and source apportionment of heavy metals. Metals were found to exist in a diffuse distribution with heterogeneous intensities and intense hot-spots of <10 μm within the fine particles. Zn-Cu, Pb-Fe and Fe-Mn-Cr had significant correlations in terms of spatial distribution. The overlapped enrichment, spatial association, and the mineral phases of metals revealed the potential sources of fine particles from size-reduced waste fractions (such as scraps of organic wastes or ceramics) or from the importation of other particles. The diverse sources of heavy metal pollutants within the fine particles suggested that separate collection and treatment of the biodegradable waste fraction (such as food waste) is a preferable means of facilitating the beneficial utilization of the stabilized products., (Copyright © 2014. Published by Elsevier B.V.)

Abstract: The low-temperature magnetic properties of Fe1− x Cr x nanoparticles with various chromium content (x=2.4−83.0at%) have been studied. The multiphase particles (α-FeCr, σ-FeCr and Fe/Cr oxides) have a core (metallic)–shell (oxide) structure. The magnetic properties of the Fe–Cr systems depend on the chromium content as well as on the types and relative contributions of the constituent crystalline phases but, in particular, they are determined by long-range interparticle dipolar interactions. The role of the weakly magnetic σ-FeCr phase is also discussed. [Copyright &y& Elsevier]

Abstract: The influence of different M2+ cations on the effective magnetic anisotropy of systems composed of MFe2O4 (M=Fe, Co and Mn) nanoparticles was investigated. Samples were prepared by the high-temperature (538K) solution phase reaction of Fe (acac)3, Co (acac)2 and Mn (acac)2 with 1,2 octanodiol in the presence of oleic acid and oleylamine. The final particles are coated by an organic layer of oleic acid that prevents agglomeration. Transmission electron microscopy (TEM) images show that particles present near spherical form and a narrow grain size distribution, with mean diameters in the range of 4.5–7.6nm. Powder samples were analyzed by ac susceptibility and Mössbauer measurements, and K eff for all samples was evaluated using both techniques, showing a strong dependence on the nature of the divalent cation. [Copyright &y& Elsevier]

Abstract: The magnetization enhancement in nanoscale mechanosynthesized MgFe2O4 is reported and is discussed in terms of a modified core–shell model, in which a competition between the effects of spin canting and site exchange of cations plays a decisive role. Because of the nearly random distribution of cations, the surface shell of nanoparticles exhibits an effective magnetic moment that is about 2 times larger than that of the particle core. The thickness of the “magnetically active” surface shell is calculated from the size-dependent magnetization measurements. [Copyright &y& Elsevier]

Abstract: A large-scale continuous stirred media mill called the MaxxMill® system in dry mode was used to investigate the comminution characteristics. A limestone powder below 2 mm was used as a feed material. A statistical experimental design was prepared with the major influencing parameters of the MaxxMill®, such as rotational speed of stirrer, feed rate and bead size. The fineness of the ground products obtained under various conditions of the MaxxMill® and the corresponding energy utilisation have been evaluated and analysed. The results have been empirically correlated with the operating parameters. In addition, product size–energy input relations can be described empirically, independent of the parameters used. [Copyright &y& Elsevier]

Epidemiologic evidence for an association between black carbon (BC) and health outcomes is limited. We estimated associations and exposure-response relationships between childhood asthma admission and concentration of BC and PM2.5 (particle less than 2.5mm in aerodynamic diameter) in ambient air in Shanghai using a lag distributed model. The PM2.5 and the BC were significantly associated with childhood asthma admissions in single-pollution model. However, the effects of BC on asthma attacks were slightly stronger than those of PM2.5 after adjusting or not adjusting for NO2 and SO2. In conclusion, our study suggests combustion-associated particles are important in China. Black carbon should be considered as one of the air quality indicators in China., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Indoor and outdoor concentrations of airborne fine particles from internal combustion engines have been measured over periods of 24 h with a time resolution of 10 s. With this time series, the ventilation air exchange rate of different rooms has been computed using a novel approach to the solution of the mass balance equation. A 'mixing time'parameter has been introduced in order to account for the initial non-homogeneous distribution of the pollutants in the rooms. It is demonstrated that this method can be used to determine the impact of health-relevant outdoor particles on the indoor particle concentration. This yields information on the protection a building offers against pollutants entering from outdoors. [ABSTRACT FROM AUTHOR]

The adjuvant effects of various fine particles \[Kanto loam dust, fly ash, carbon black, diesel exhaust particles (DEP), and aluminum hydroxide (alum)] on immunoglobulin E (IgE) antibody production in female BDF mice were examined. In experiment 1, animals both 1 received 25g of each particle intranasally and were exposed to aerosolized Japanese cedar pollen allergens (JCPA) for 30 min/d at 1-wk intervals forthe first 8 wk. This was followed by exposure for 30 min every 3 wk for the next 9 wk. As parameters of allergic rhinitis, measurements were made of JCPA-specific IgE and IgG antibody titers, the proteinadsorbing capacity of each type of particle, and nasal rubbing movements. The increases in anti-JCPA IgE and IgG antibody production in mice treated with aerosolized JCPA plus respective particles were significantly greater than that found with aerosolized JCPA alone. This was associated with no marked differences in the other allergic rhinitis parameters. In experiment 2, after the administration of particles as in experiment 1, about 160,000 grains of Japanese cedar pollen (JCP, native dry pollen) were dropped onto the tip of the nose of mice twice a week for 16 wk. Six weeks after the first immunization, the anti-JCPA IgE antibody titers of groups treated with the respective particles were greater than 1:20, whereas those of mice treated with JCP alone were 1:10. No significant differences in the anti-JCPA IgE and IgG antibody productions, nasal rubbing counts, or histopathological changes were observed after 18 wk. These results suggested the nature of the particles, their capacity to adsorb antigens, and/or their sizemay not be related to enhancement of IgE antibody production nor symptoms of allergic rhinitis. However, IgE antibody production seemed to occur earlier in mice treated with particles than in mice immunizedwith allergens alone. [ABSTRACT FROM AUTHOR]