家用报警系统DIY实例

当前市场上的各种报警系统种类繁多,各类制造商也是比比皆是,消费者可以随心所欲地选择他们喜欢的系统。各类系统之间的差别也非常有限,下面我们来介绍一套报警设备的DIY方案,供读者参考(由Alicia示范)。     

城市空气中多环芳烃定量测定方法

本文发展了一种对城市空气中多环芳烃(PAH)定量测定的方法。该方法可以用极少量溶剂,相当快地完成测定工作。     

天然水、土壤和岩石中金与腐殖质的相互作用(地球化学和分析综述)

对天然水、土壤和岩石中金与腐殖质相互作用的结果及Au一腐殖酸和AUCL-腐殖酸在体系中相互作用的实验资料进行了研究。研究表明，金与腐殖酸有机质形成配合物的过程，乃是表生带中金的迁移和富集机制的一个重要方面，决定了从联质矿石中萃取金的工艺特点，影响到岩石、矿石、土壤和天然水中金的测定准确性，进而对金矿床普查和评价的效率有决定性的影响。     

Sustainable Development and Strategic Thinking

From an economic point of view, the industrial economy is efficient to overcome situations of a scarcity of goods. From a technological point of view, the resource efficiency of the manufacturing processes of the industrial economy has been permanently improved during the last 200 years. In addition, cleaner processes have been developed. However, from an ecologic point of view, an increasing world population with increasing consumption has produced a ＂global footprint＂ which approaches the carrying capacity of the planet. A circular economy and its high-value spin-offs-a lake economy and a performance or functional service economy-can fulfil customers＇ needs with considerably less resource consumption, less environmental impairment in production and considerably less end-of-life product waste, especially in situations of affluence, when a considerable stock of physical goods and infrastructures exists. Also, in situations of a scarcity of natural resources, both energy and materials, often characterised by rapidly rising resource prices, the economic actors of a circular economy have a high competitive advantage over the actors of the industrial economy, due to much lower procurement costs for materials and energy. From a social point of view, a circular economy increases the number of skilled jobs in regional enterprises. However, the shift from a linear manufacturing economy to a circular or service economy means a change in economic thinking from flow （throughput） management to stock （asset） management： in a manufacturing economy with largely unsaturated markets, total wealth increases through accumulation as resource throughput （flow） is transformed into a higher stock of goods of better quality （but in a manufacturing economy with largely saturated markets, wealth represented by the stock of goods will no longer increase）; in a circular or service economy, total wealth increases through a smart management of existing physical assets （stock） that are adapted to changes in both technology and customer demand. This second approach not only applies to physical capital but equally to social capital, such as health and education and green GDP. To measure the social wealth of a population, it is not the amount of money spent on schools and hospitals that matters, butif this expenditure has led to a better education of the students, and a better health of the people.     

塞浦路斯的地震危险性

<正> 1 地震危险性评定历史地震危险性评定在塞浦路斯虽处于初始阶段,但并未忽视其重要性。地震危险性评定对结构(如构筑物和大坝)的设计安全性参数确定所起的关键作用已有充分认识。到目前为止,已进行了两个场地的地震危险性评定。第一项是确定一大坝坝址预期最大可能地面加速度(Neophyton,1981),第二项估计尼科西亚老城墙以内地区不同烈度地震过程中人员及财产可能损失(Constantinon,1990),研究结果公布于地质调查局的内部报告上。对市区及近郊的岩土工程编图方面,也做了大量工作。测定了Larnaca镇沿海地区的潜在疑难层,如冲积层和高有机含量沉积层(Michaelides,1988)。在塞浦路斯,尽管全国地震危险性图有震中分布图(公元前180～公元1972年)、具有预期最大地面加速度值的观测烈度带图(公元前180～公元1980)和最大能量释放带图(1901～1972),但至今尚未进行综合地震危险性评定研究。     

Characterization of atmospheric aerosol (PM10 and PM2.5) from a medium sized city in São Paulo state, Brazil

Air pollution causes deleterious effects on human health with aerosols being among the most polluting agents.The objective of this work is the characterization of the PM_(2.5) and PM_(10) aerosol mass in the atmosphere.The methods of analysis include WD-XRF and EDS.Data were correlated with meteorological information and air mass trajectories(model HYSPLIT)by multivariate analysis.A morphological structural analysis was also carried out to identify the probable sources of atmospheric aerosols in the city of Sao Jose do Rio Preto,Brazil.The mean mass concentration values obtained were 24.54 μg/m~3 for PM_(10),above the WHO annual standard value of 20 μg/m~3 and 10.88 μg/m~3 for PM_(2.5) whose WHO recommended limit is10 μg/m~3.WD-XRF analysis of the samples revealed Si and Al as major components of the coarse fraction.In the fine fraction,the major elements were Al and S.The SEM-FEG characterization allowed identifying the morphology of the particles in agglomerates,ellipsoids and filaments in the PM_(10),besides spherical in the PM_(2.5).The analysis by EDS corroborated WD-XRF results,identifying the crustal elements,aluminosilicates and elements of anthropogenic origin in the coarse fraction.For the fine fraction crustal elements were also identified;aluminosilicates,black carbon and spherical particles(C and O) originating from combustion processes were predominant.The use of multivariate analysis to correlate air mass trajectories with the results of the morpho-structural characterization of the particulate matter allowed confirmation of the complex composition of the particles resulting from the combination of both local and long-distance sources.     

Reactive uptake of NO2 on volcanic particles: A possible source of HONO in the atmosphere

The heterogeneous degradation of nitrogen dioxide (NO₂) on five samples of natural Icelandic volcanic particles has been investigated. Laboratory experiments were carried out under simulated atmospheric conditions using a coated wall flow tube (CWFT). The CWFT reactor was coupled to a blue light nitrogen oxides analyzer (NO_x analyzer), and a long path absorption photometer (LOPAP) to monitor in real time the concentrations of NO₂, NO and HONO, respectively. Under dark and ambient relative humidity conditions, the steady state uptake coefficients of NO₂ varied significantly between the volcanic samples probably due to differences in magma composition and morphological variation related with the density of surface OH groups. The irradiation of the surface with simulated sunlight enhanced the uptake coefficients by a factor of three indicating that photo-induced processes on the surface of the dust occur. Furthermore, the product yields of NO and HONO were determined under both dark and simulated sunlight conditions. The relative humidity was found to influence the distribution of gaseous products, promoting the formation of gaseous HONO. A detailed reaction mechanism is proposed that supports our experimental observations. Regarding the atmospheric implications, our results suggest that the NO₂ degradation on volcanic particles and the corresponding formation of HONO is expected to be significant during volcanic dust storms or after a volcanic eruption.     

Mercury levels in human population from a mining district in Western Colombia

A biomonitoring study was carried out to examine the adverse impacts of total mercury in the blood(HgB), urine(Hg U) and human scalp hair(HgH) on the residents of a mining district in Colombia. Representative biological samples(scalp hair, urine and blood) were collected from volunteered participants(n = 63) to estimate the exposure levels of THg using a Direct mercury analyzer. The geometric mean of THg concentrations in the hair,urine and blood of males were 15.98 μg/g, 23.89 μg/L and 11.29 μg/L respectively, whereas the females presented values of 8.55 μg/g, 5.37 μg/L and 8.80 μg/L. Chronic urinary Hg(HgU)levels observed in male workers(32.53 μg/L) are attributed to their long termed exposures to inorganic and metallic mercury from gold panning activities. On an average, the levels of THg are increasing from blood(10.05 μg/L) to hair(12.27 μg/g) to urine(14.63 μg/L).Significant positive correlation was found between hair and blood urinary levels in both male and female individuals. Thus the present biomonitoring investigation to evaluate the Hg levels and associated health issues would positively form a framework for further developmental plans and policies in building an ecofriendly ecosystem.     

Shelter, housing and recovery: a comparison of u.s. Disasters

In this paper we examine the issues associated with the temporary sheltering and housing of victims after natural disasters in the United States. Specific topics addressed include differential access to shelter and housing aid according to social class, ethnicity and related demographic factors; the relationship between post-disaster shelter and housing and long-term recovery; the role of social support networks in the sheltering of victims; and the implications of the research for the provision of shelter and housing aid after disasters.     

Recycling of petroleum-contaminated sand

The environmental impact of using petroleum-contaminated sand (PCS) as a substitute in asphalt paving mixtures was examined. An appreciable component of PCS is oily sludge, which is found as the dregs in oil storage tanks and is also produced as a result of oil spills on clean sand. The current method for the disposal of oily sludge is land farming. However, this method has not been successful as an oil content of < 1% w/w is required, and difficulty was encountered in reaching this target. The reuse of the sludge in asphalt paving mixtures was therefore considered as an alternative. Standard tests and environmental studies were conducted to establish the integrity of the materials containing the recycled sludge. These included physical and chemical characterization of the sludge itself, and an assessment of the mechanical properties of materials containing 0%, 5%, 22% and 50% oily sludge. The blended mixtures were subjected to special tests, such as Marshall testing and the determination of stability and flow properties. The experimental results indicated that mixtures containing up to 22% oily sludge could meet the necessary criteria for a specific asphalt concrete wearing course or bituminous base course. To maximize the assay from the recycled material, the environmental assessment was restricted to the 50% oily sludge mixture. Leachates associated with this particular mixture were assayed for total organic residue and certain hazardous metal contaminants. The results revealed that the organics were negligible, and the concentrations of the metals were not significant. Thus, no adverse environmental impact should be anticipated from the use of the recycled product. Our research showed that the disposal of oily sludge in asphalt paving mixtures could possibly yield considerable savings per tonne of asphalt concrete, and concurrently minimize any direct impact on the environment.