改性竹活性炭去除汞离子

采用溴化钾、碘化钾和硫磺对竹活性炭掺杂改性,利用电感耦合等离子体发射光谱仪测定滤液中汞离子浓度,用除汞效率和吸附容量评价活性炭对溶液中汞离子的吸附性能,探讨其吸附机理。结果表明,掺杂改性明显提高了竹活性炭的除汞性能。原竹活性炭的除汞效率为78.6%,吸附容量为2.210 mg/g;经碘化钾、溴化钾和硫磺掺杂改性后的竹活性炭除汞效率分别为94.3%、93.8%和88.8%,吸附容量分别为2.830、2.813和2.663 mg/g;经溴化钾(碘化钾)和硫磺联合改性的竹活性炭对水溶液中汞离子的吸附性能性能又有提高,其中以先载硫后载溴化钾的方法除汞效果最好,除汞效率达96.6%,吸附容量为2.898 mg/g。     

温度对阶段培养法建立高盐生物系统的影响

腌制废水具有高有机物、含盐量高(7%左右)等特点,废水可生化性在0.4左右,其处理的最大难点在于生化性较差影响正常生物方法的处理和生化段高盐生物系统的建立;本实验主要针对水解酸化工艺,考察了利用阶段培养法建立高盐生物系统的效果及温度对高盐生物系统的影响,实验结果表明,在中温((28±2)℃)下利用阶段培养法可以建立良好的高盐生物系统,对含盐量在5.5%左右的腌制废水处理效果良好,废水B/C由0.4提高为0.6左右,COD去除率为23.81%,微生物活性温度在28.11 mg/L,挥发性脂肪酸(VFA)为34 mmol/L。     

Can conservation of single surrogate species protect co-occurring species?

Conservation of surrogate species is expected to benefit co-occurring species with similar distributions that share the same habitat, yet the usefulness of this approach to protect nontarget species has been extensively challenged. In this study, we aimed to assess whether co-occurring species could be afforded protection under the conservation of two proposed surrogate species, the giant panda and the takin. We undertook a thorough study on the habitat requirements of these two endangered species, based on the analysis of their habitat preferences. The results revealed that the giant panda exhibits more specialized habitat preferences than does the takin and that habitat separation between these species mainly reflected differences in their dietary requirements and preferences. We suggest that these differences might facilitate their coexistence in sympatric areas. Meanwhile, results of a discriminant function analysis showed that protection of giant pandas would protect 82.1 % of the panda’s habitat, but only 25.4 % of the takin’s habitat and just 57.0 % of the joint habitats of these species. Importantly, our results also showed that a joint surrogate species approach to conservation would protect 86.9 % of the panda’s habitat, 53.7 % of the takin’s habitat, and 72.2 % of the joint habitats of these species. This is a higher degree of habitat protection than the single surrogate conservation of pandas. We conclude that the joint surrogate species approach should be adopted to improve biodiversity conservation.     

1986 APCA Government Agencies Directory

Carbonaceous species (organic carbon [OC] and elemental carbon [EC]) and inorganic ions of particulate matter less than 2.5 μm (PM_2.5) were measured to investigate the chemical characteristics of long-range-transported (LTP) PM_2.5 at Gosan, Jeju Island, in Korea in the spring and fall of 2008–2012 (excluding 2010). On average, the non-sea-salt (nss) sulfate (4.2 µg/m³) was the most dominant species in the spring, followed by OC (2.6 µg/m³), nitrate (2.1 µg/m³), ammonium (1.7 µg/m³), and EC (0.6 µg/m³). In the fall, the nss-sulfate (4.7 µg/m³) was also the most dominant species, followed by OC (4.0 µg/m³), ammonium (1.7 µg/m³), nitrate (1.1 µg/m³), and EC (0.7 µg/m³). Both sulfate and OC were higher in the fall than in the spring, possibly due to more common northwest air masses (i.e., coming from China and Korea polluted areas) and more frequent biomass burnings in the fall. There was no clear difference in the EC between the spring and fall. The correlation between OC and EC was not strong; thus, the OC measured at Gosan was likely transported across a long distance and was not necessarily produced in a manner similar to the EC. Distinct types of LTP events (i.e., sulfate-dominant LTP versus OC-dominant LTP) were observed. In the sulfate-dominant LTP events, air masses directly arrived at Gosan without passing over the Korean Peninsula from the industrial area of China within 48 hr. During these events, the aerosol optical depth (AOD) increased to 1.63. Ionic balance data suggest that the long-range transported aerosols are acidic. In the OC-dominant LTP event, a higher residence time of air masses in Korea was observed (the air masses departing from the mainland of China arrived at the sampling site after passing Korea within 60–80 hr).

Implications:?In Northeast Asia, various natural and anthropogenic sources contribute to the complex chemical components and affect local/regional air quality and climate change. Chemical characteristics of long-range-transported (LTP) PM_2.5 were investigated during spring and fall of 2008, 2009, 2011, and 2012. Based on air mass types, sulfate-dominant LTP and OC-dominant LTP were observed. A long-term variation and chemical characteristics of PM_2.5 along with air mass and satellite data are required to better understand long-range-transported aerosols.     

Physicochemical properties of chars at different treatment temperatures

In this study, the physicochemical properties of the char of Indonesian SM coal following heat treatment at various temperatures were evaluated using X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and morphological and specific surface area analysis. Based on these analyses, heat treatment of coal was determined to be the most effective in increasing the coal rank. In the XPS analysis, the C–O and C–O–C groups and quaternary-N species were found to be of a lower grade coal when the pretreatment temperature decreased, meanwhile the C–C group and pyridinic species increased. In the FT-IR analysis, the collapse of the C–O and C–O–C group was observed due to the collapse of the ether group. In SEM and Brunauer–Emmett–Teller (BET) analysis, a decrease in the ether group was shown to be accompanied with the formation of micropores.

Implications Recently, XPS analyses have been reported as coal surface analysis. Usually, they have reported the analysis of the coals with different rank. This study investigated the coal surface characteristics of the coals pretreated at different temperature using various analyses (BET, SEM, XPS, FT-IR), and this study can be the basis for other research and applications.     

Assessment and distribution of antimony in soils around three coal mines, Anhui, China

Thirty-three soil samples were collected from the Luling, Liuer, and Zhangji coal mines in the Huaibei and Huainan areas of Anhui Province, China. The samples were analyzed for antimony (Sb) by inductively coupled plasma-optical emission spectrometry (ICP-OES) method. The average Sb content in the 33 samples was 4 mg kg(-1), which is lower than in coals from this region (6.2 mg kg(-1)). More than 75% of the soils sampled showed a significant degree of Sb pollution (enrichment factors [EFs] 5-20). The soils collected near the gob pile and coal preparation plant were higher in Sb content than those collected from residential areas near the mines. The gob pile and tailings from the preparation plant were high in mineral matter content and high in Sb. They are the sources of Sb pollution in surface soils in the vicinity of coal mines. The spatial dispersion of Sb in surface soil in the mine region shows that Sb pollution could reach out as far as 350 m into the local environment conditions. Crops in rice paddies may adsorb some Sb and reduce the Sb content in soils from paddyfields. Vertical distribution of Sb in two soil profiles indicates that Sb is normally relatively immobile in soils.     

稻壳基活性炭的制备及其对亚甲基蓝吸附的研究

以稻壳为原料,采用K2CO3活化法和H3P04活化法制备了比表面积为1312m^2／g和682m^2／g的活性炭,通过扫描电子显微镜（SEM）、X-射线衍射仪（XRD）对样品进行了表征,并将孔隙发达的活性炭样品用于对亚甲基蓝的吸附,结果表明,K2CO3活化法制备的活性炭样品具有更多的微孔结构;随着亚甲基蓝溶液初始浓度的增加、活性炭吸附时间的延长,亚甲基蓝的去除率呈现逐渐降低和逐渐增大的变化规律,当pH值为6时,活性炭对亚甲基蓝的吸附效果最佳;稻壳基活性炭对亚甲基蓝的吸附等温线符合Langmuir模型,Qm最高可达476．2mg／g;热力学参数△G^0△H^0和△S^0均为负值,表明稻壳基活性炭对亚甲基蓝的吸附是一个自发的放热反应。     

Bacteria inactivation by sulfate radical: progress and non-negligible disinfection by-products

● Status of inactivation of pathogenic microorganisms by SO₄^•− is reviewed. ● Mechanism of SO₄^•− disinfection is outlined. ● Possible generation of DBPs during disinfection using SO₄^•− is discussed. ● Possible problems and challenges of using SO₄^•− for disinfection are presented. Sulfate radicals have been increasingly used for the pathogen inactivation due to their strong redox ability and high selectivity for electron-rich species in the last decade. The application of sulfate radicals in water disinfection has become a very promising technology. However, there is currently a lack of reviews of sulfate radicals inactivated pathogenic microorganisms. At the same time, less attention has been paid to disinfection by-products produced by the use of sulfate radicals to inactivate microorganisms. This paper begins with a brief overview of sulfate radicals’ properties. Then, the progress in water disinfection by sulfate radicals is summarized. The mechanism and inactivation kinetics of inactivating microorganisms are briefly described. After that, the disinfection by-products produced by reactions of sulfate radicals with chlorine, bromine, iodide ions and organic halogens in water are also discussed. In response to these possible challenges, this article concludes with some specific solutions and future research directions.     

Antecedents of early career stage mentoring among Chinese employees

This study examined the mediating influence of protege‐initiated mentoring relationships on the relationship between personality and situational characteristics and mentoring received. Data were obtained from Hong Kong Chinese graduate employees (N=184) in their early career stage. Results of the regression analysis showed that protege‐initiated mentoring relationships mediated the relationship between the personality (extraversion) but not the situational (individual development culture and opportunities for interactions on the job) characteristics and mentoring received. In other words, extraversion was indirectly related to mentoring received through protege‐initiated mentoring relationships but individual development culture and opportunities for interactions on the job were directly related to mentoring received. Additionally, opportunities for interactions on the job indirectly influenced mentoring received through protege‐initiated mentoring relationships. Limitations of the study, implications of the findings and directions for future research are discussed. Copyright © 1999 John Wiley & Sons, Ltd.     

Analysis of injury mechanism of the elderly and non-elderly groups in minor motor vehicle accidents

Abstract

Objective: The purpose of this study is to investigate the injury patterns of noncatastrophic accidents by individual age groups.

Methods: Data were collected from the Korean In-Depth Accident Study database based on actual accident investigation. The noncatastrophic criteria were classified according to U.S. experts from the Centers for Disease Control and Prevention’s recommendations for field triage guidelines of high-risk automobile crash criteria by vehicle intrusions more than 12 in. on occupant sites (including the roof) and more than 18 in. on any site. The Abbreviated Injury Scale (AIS) was used to determine injury patterns for each body region. Severely injured patients were classified as Maximum Abbreviated Injury Scale (MAIS) 3 or higher.

Results: In this study, the most significant injury regions were the head and neck, extremities, and thorax. In addition, the incidence of severe injury among elderly patients was nearly 1.6 times higher than that of non-elderly patients. According to age group, injured body regions among the elderly were the thorax, head and neck, and extremities, in that order. For the non-elderly groups, these were head and neck, extremities, and thorax. Severe injury rates were slightly different for the elderly group (head and neck, abdomen) and non-elderly group (thorax, head and neck).

Conclusions: In both age groups, the rate of severe injury is proportional to an increase in crush extent zone. Front airbag deployment may have a relatively significant relationship to severe injuries.