Determination of chemical characterizations of activated carbons from various raw materials

The objectives of this research were to identify the surface chemical features of activated carbons made of peat, bituminous coal and coconut shell, as well as examine the specific relationship of these properties by using statistical analyses. The results showed that the peat carbons contained much more amounts of Ca, S, P and Mg; however, the bituminous carbons possessed higher contents of Si, Al and Fe. In addition, the content ratios of Al to Si exhibited the Al enrichment phenomenon occurred after the heat treatment. A nonlinear correlation between the pH value and the difference in the amounts of basic and acidic groups was developed. Unfortunately, there were no specific mass ratios found among the acidic functional groups. The results of correspondence analysis (CA) gave a promising confirmation about the EDXRF analysis; moreover, the results of factor analysis (FA) fairly agreed with the findings suggested by CA. Both could explain the specific chemical features of activated carbons made from different materials, especially the CA could differentiate each other in detail.     

Warning signals confer advantage to prey in competition with predators: bumblebees steal nests from insectivorous birds

Aposematic (warning) signals of prey help predators to recognize the defended distasteful or poisonous prey that should be avoided. The evolution of aposematism in the context of predation has been in the center of modern ecology for a long time. But, the possible roles of aposematic signals in other ecological contexts have been largely ignored. Here we address the role of aposematic signals in competition between prey and predators. Bumblebees use visual and auditory aposematic signals to warn predators about their defenses. For 2 years, we observed competition for nestboxes between chemically defended insects, Bombus ardens (and possibly also Bombus ignitus), and cavity nesting birds (Parus minor and Poecile varius). Bumblebees settled in 16 and 9 % of nestboxes (in 2010 and 2011 breeding seasons, respectively) that contained bird nests at the advanced stage of nest building or at the stage of egg laying. Presence of bumblebees prevented the birds from continuing the breeding activities in the nestboxes, while insects took over the birds’ nests (a form of kleptoparasitism). Playback experiments showed that the warning buzz by bumblebees contributed to the success in ousting the birds from their nests. This demonstrates that aposematic signals may be beneficial also in the context of resource competition.     

Temporal variability in atmospheric Hg released from natural and anthropogenic sources in central Taiwan

From September 2011 to February 2012, ambient air particulate and particulate-bound mercury [Hg(p)] concentrations were measured, together with dry deposition using a cold vapor atomic fluorescence spectrometry (CVAFS) analyser, at two characteristic sampling sites in central Taiwan. Results from the sampling site at Westin Park indicated that the lowest particulate dry deposition and lowest average particulate concentrations in total suspended particles (TSP) occurred in September (29.70±7.47 μ g m^?2×min) and February (34.38±13.60 ng m^?3), respectively. Moreover, results from the Gung-Ming junior high school (airport) site, showed that the highest average particulate dry deposition and average highest particulate concentrations in TSP occurred in February (156.76±30.36 μ g m^?2×min) and January (125.49±9.51 ng m^?3), respectively, during the winter. The Dragon Steel Plant and Han-Shian Aerospace Industrial Development Corporation were both nearby. These factors led to the high Hg(p) concentrations at Taichung Airport (TA) compared with Westin Park. Local large suspended particulates from heavy traffic were the main reason for the high average Hg(p) deposition at Westin Park compared with TA in this study.     

强震区小流域泥石流发育特征研究——以四川省绵竹市罗家沟泥石流为例

小流域泥石流因流域面积小,常被人们忽略或未引起足够的重视,却往往造成较大灾害损失;2010年8月13日绵竹市清平乡罗家沟暴发泥石流,一次冲出量约30万m3,而该沟流域面积仅1.4 km2;此次泥石流造成主沟沟口民房被掩埋,1.5 km的道路被毁,3座涵洞、一座小桥被冲毁,并使绵远河改道约200 m左右,直接经济损失约500万.根据现场调查和航空图像解译,分析了泥石流成因,讨论了泥石流形成、运动和堆积过程,并计算了泥石流的力学参数;罗家沟泥石流的实例表明汶川震区小流域泥石流具有较强的隐蔽性和破坏力.因此,在对汶川震区泥石流开展调查和评估工作时,尤其应注意小流域泥石流调查工作,必要时应进行相应的工程治理措施.     

Sources and Distribution of Heavy Metals in East China Sea Surface Sediments

Box cores and surficial sediments collected from the shelf, slope and Okinawa Trough of the East China Sea were analyzed for loss on ignition, and concentration and speciation of Al, Fe, Mn, Pb, Cd, Cu and Zn. in general, concentrations of these metals are higher in the inner shelf and lower in the midshelf, but the highest LOI, Cd and Mn levels are found in the Okinawa Trough. Spatial distributions of these metals in surficial sediments indicate that the Yangtze River is the major source for materials deposited in the inner shelf. the results of a six-stage sequential leaching experiment indicate that the fluvial input includes natural (e.g., Al and Fe) and anthropogenic (e.g., Pb) materials. the depletion concentration of these metals in the midshelf sediments reflects the dominance (～ 70%) of coarse, relict sand, while the enrichments in the inner shelf and the Okinawa Trough sediments are due to the fine grained, organic-rich sediments. the speciation of Mn in the sediments of the Okinawa Trough indicates that its distribution is diagentically or hydrothermally controlled.     

Oyster shell reduces PAHs and particulate matter from incense burning

This is the first report showing reduction of particle matter and PAHs from incense burning by addition of oyster shell. Worshiping ancestors and gods by burning incense sticks and joss paper is a very important tradition in many Asian regions. More than 45 % of families in Taiwan burn incense twice a day. Unlike joss paper burning, most of the incense burning occurs indoors, thus creating a risk for human health. Previous reports have indeed evidenced toxicity of incense, notably due to particulate matter and polycyclic aromatic hydrocarbons (PAHs). However, there are few methods to reduce particle matter and PAHs from incense burning. We hypothesize that oyster shell may be used to reduce incense fumes toxicity. Indeed a large amount of unused oyster shell is discarded due to increasing seafood consumption. Here, two types of incense were made in the laboratory, and then 5–30 % of oyster shells were added to the incense to study the reduction of particle matter and PAHs. Results show that reduction of particle matter and PAH emission increased with oyster shell addition. The reduction of emission factors is ?35 % for mean particle matter, ?21 % for particle-phase PAHs, and ?37 % for benzo[a]pyrene equivalent concentration (BaP_eq), using 30 % oyster shell additive. The addition of 10 % oyster shell reduces the burning time by 8.3 min, increases the burning rate by 3.4 mg/min, and reduces particle matter by 6.4 mg/g incense, particle-phase PAHs by 0.67 μg/g incense, and BaP_eq by 0.23 μg/g incense. The reductions of particle matter, particle-phase PAHs, and BaP_eq correspond to about 640 metric tons, 67, and 23 kg, respectively, per year. Our findings will help to produce safer and cleaner incense.     

矸石山不同造林模式对土壤养分及酶活性影响的研究

本文以抚顺矸石山立地条件下树龄为10年的刺槐Robinia pseudoacacia L.、火炬Rhus typhina Nutt、白榆Ulmus pumila L.、沙棘Hippophae rhamnoides L.林以及植被自然恢复裸地（CK）5种植被恢复模式为研究对象,按土壤发生学层次进行采样,对土壤有机质、碱解氮、有效磷、速效钾、pH、过氧化氢酶、蔗糖酶和脲酶等指标进行研究,结果表明：与CK相比,4种造林模式显著提高了Ah层的土壤有机质和养分含量,其中,有机质、有效磷改良效果最好的是白榆模式,分别增加了194.8%、442.9%;速效钾改良效果最好的是刺槐模式,增加了262.0%;碱解氮则是火炬模式改良效果最好,增加了509.2%。不同造林模式与CK相比增加了各层次的过氧化氢酶、脲酶、蔗糖酶活性,其中,蔗糖酶和过氧化氢酶活性Ah层最大的是火炬模式,增加了134.5%和880.9%;脲酶酶活性最大的是白榆模式,增加了119.1%。从垂直角度看,有机质、碱解氮、过氧化氢酶、脲酶随土层加深含量降低,在C层达到最小值,而速效钾、有效磷、蔗糖酶的最小值则出现在AC层;不同模式对土壤pH影响不一,垂直规律不明显。     

Preparation and characterization of surface modified powder of calcium hydroxide used as chlorine scavenger

In order to avoid existing shortcomings of chlorine leakage treatment, we developed a new chlorine scavenger. The main composition of the chlorine scavenger was calcium hydroxide. The chlorine scavenger was prepared by wet process with water as solvent through adding surface active agent and silicone oil, etc. The influence of surfactant on modified powder was investigated, which included the sodium dodecyl benzene sulfonate, the sodium stearate, the water-soluble silicone oil, the emulsifying silicon oil and the amino silicone oil, and the effect of modification of judgment were illustrated, which mainly involved the sifting rate, the bulk density, the contact angle, on this basis, also the author analyzed the powder of modification by using SEM analysis and size distribution, The modified powder had the following characteristics: high absorptivity, anti-caking, good air permeability and so on. The results showed that overall performance of modified powder was better than the performance of unmodified powder. The adding amount of sodium stearate was preferably 2% while the optimum amount of emulsifying silicon oil and amino silicone oil was 3%. The comprehensive performance of powder modified with compound modifiers was better than the performance of the powder modified with a single modifier. The property of powder modified with sodium stearate and amino silicone oil had a good performance analyzed from the uniformity of particle size distribution of the powder and anti-caking. The powder modified with sodium stearate and emulsifying silicon oil had a good absorption rate of chlorine.     

Green thermal analysis for predicting thermal hazard of storage and transportation safety for tert-butyl peroxybenzoate

Liquid organic peroxides, such as tert-butyl peroxybenzoate (TBPB), have been widely employed in the petrifaction industry as a polymerization formation agent. This study investigated the thermokinetic parameters of TBPB by isothermal kinetic algorithms and non-isothermal kinetic equations, using thermal activity monitor III (TAM III) and differential scanning calorimetry (DSC), respectively. Simulations of 0.5 L, 25 kg, 55 gallon, and 400 kg reactors in liquid thermal explosion models were performed and compared to the results in the literature. A green thermal analysis was developed for a reactor containing TBPB to prevent pollution and reduce the energy consumption by thermal decomposition. It is based on the thermal hazard properties, such as the heat of decomposition (ΔH_d), activation energy (E_a), self-accelerating decomposition temperature (SADT), control temperature (CT), emergency temperature (ET), and critical temperature (TCR). From the experimental results, the optimal conditions to avoid violent runaway reactions during the storage and transportation of TBPB were determined.     

重气扩散研究现状与进展

从重气扩散机理出发,分析了重气的形成原因、扩散过程及扩散影响因素。概述了国内外开展的一系列试验,总结了重气扩散数学模型的研究现状。指出重气扩散的进一步研究应该充分考虑气体多相组分与初始释放状态以及热效应等对扩散过程的影响,并在此基础上建立起能反映真实复杂体系流动的数学模型。