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31.
Juheon Lee 《Disasters》2021,45(1):158-179
This study aimed to assess the multi‐level effects of natural hazards on trust in Chinese society. Drawing on the Chinese General Social Survey conducted in 2012 and provincial disaster damage records, it examined the association between individuals’ past experiences of disasters and province‐level damage (measured by the number of affected people, deaths, and economic loss) and various forms of trust: in‐group; out‐group; generalised; and political. The findings indicate that Chinese individuals with experience of disasters have higher levels of out‐group trust but lower levels of political trust. Similarly, at the province level, damage owing to disasters over the past three years (2009–11) positively impacted on residents’ out‐group trust while negatively affecting their political trust. However, when provincial damage was aggregated for disasters over the past five years (2007–11), which included the devastating Sichuan earthquake on 12 May 2008, only total deaths had a positive effect on generalised trust.  相似文献   
32.
Real-time quantitative polymerase chain reaction (qPCR) has gained popularity as a technique to detect and quantify a specific group of target microorganisms from various environmental samples including soil, water, sediments, and sludge. Although qPCR is a very useful technique for nucleic acid quantification, accurately quantifying the target microbial group strongly depends on the quality of the primer and probe used. Many aspects of conducting qPCR assays have become increasingly routine and automated; however, one of the most important aspects, designing and selecting primer and probe sets, is often a somewhat arcane process. In many cases, failed or non-specific amplification can be attributed to improperly designed primer-probe sets. This paper is intended to provide guidelines and general principles for designing group-specific primers and probes for qPCR assays. We demonstrate the effectiveness of these guidelines by reviewing the use of qPCR to study anaerobic processes and biologic nutrient removal processes. qPCR assays using group-specific primers and probes designed with this method, have been used to successfully quantify 16S ribosomal Ribonucleic Acid (16S rRNA) gene copy numbers from target methanogenic and ammonia-oxidizing bacteria in various laboratory- and full-scale biologic processes. Researchers with a good command of primer and probe design can use qPCR as a valuable tool to study biodiversity and to develop more efficient control strategies for biologic processes.  相似文献   
33.
Ambient air samples at ten sites in an iron and steel industrial complex were collected from June to December for analyzing polycyclic aromatic hydrocarbons (PAHs). Sixteen species of PAH components in air samples were identified. The results indicate that both gaseous phase and particle‐bound PAHs at the top of the cokemaking plants are unusually high. The profiles of particle‐bound PAHs indicate that the predominant species at the top of, the coke oven batteries are those of high molecular weight components. The major components of particle‐bound PAHs at sampling sites near the fenceline, however, include the medium molecular weight components. The PAH profiles of air samples within the industrial complex show a strong similarity to those of cokemaking plant samples. The concentrations and the specific content of benzo(a)pyrene in the iron and steel industrial complex are higher than those values measured in urban area, petrochemical industry park, and open‐air burning area.  相似文献   
34.
• A spectral machine learning approach is proposed for predicting mixed antibiotic. • Pretreatment is far simpler than traditional detection methods. • Performance of the model is compared in different influencing factors. • Spectral machine learning is promising in the detection of complex substances. Antibiotics are widely used in medicine and animal husbandry. However, due to the resistance of antibiotics to degradation, large amounts of antibiotics enter the environment, posing a potential risk to the ecosystem and public health. Therefore, the detection of antibiotics in the environment is necessary. Nevertheless, conventional detection methods usually involve complex pretreatment techniques and expensive instrumentation, which impose considerable time and economic costs. In this paper, we proposed a method for the fast detection of mixed antibiotics based on simplified pretreatment using spectral machine learning. With the help of a modified spectrometer, a large number of characteristic images were generated to map antibiotic information. The relationship between characteristic images and antibiotic concentrations was established by machine learning model. The coefficient of determination and root mean squared error were used to evaluate the prediction performance of the machine learning model. The results show that a well-trained machine learning model can accurately predict multiple antibiotic concentrations simultaneously with almost no pretreatment. The results from this study have some referential value for promoting the development of environmental detection technologies and digital environmental management strategies.  相似文献   
35.
This paper examines long-run and short-run dynamics of renewable energy consumption on carbon dioxide (CO2) emissions and economic growth in the European Union. This study employs cointegration tests, Granger causality tests and vector error correction estimates to examine the direction of Granger causality, the long-run dynamics of economic growth and energy variables on carbon emissions. This study analyses time series data from the World Development Indicators over the period from1961 to 2012. The results of this study support a link between renewable energy consumption, economic growth, industrialization, exports and CO2 emissions in the long-run and short-run. The results support that the sign of the long-run dynamics from the endogenous variables to the CO2 emissions variable is negative and significant, which implies that the energy and environmental policies of the European Union aimed at curbing CO2 emissions must have been effective in the long-term. Furthermore, renewable energy consumption and exports have significant negative impact on CO2 emissions in the short-run. However, industrialization and economic growth have positive impact on CO2 emissions in the short-run. The results suggest that both economic growth and industrialization must have been achieved at the cost of harming the environment. The finding suggests that the increasing consumption of renewable energy tends to play an important role in curbing carbon emissions in the region.  相似文献   
36.
Environmental Geochemistry and Health - The CO2-rich spring water (CSW) occurring naturally in three provinces, Kangwon (KW), Chungbuk (CB), and Gyeongbuk (GB) of South Korea was classified based...  相似文献   
37.
Particulate matter suspended in the air has adverse effects onhuman health. Its level of concentration is an important parameter in evaluating the degree of hazard it poses to the atmosphere. Conventional methods used in measuring particulatematter are often filter-based, which indicates some disadvantagesbecause such a base requires labor and time. In this study, to achieve real-time measurements, a new electrical method was developed for measuring PM10 and PM2.5 concentrations. The basicprinciple is to electrically charge particles passing through thePM inlet using a corona charger and measure the currents createdby charged particles to obtain the number concentration of particulate matter. A new type inlet based on the particle cupimpactor configuration was designed and its performance was evaluated. A unipolar diffusion charger was developed and thecharger's efficiency was determined experimentally in terms ofPn, which represents the penetration through the charger,P, times the average charge number acquired by a particle,n, for different particle sizes. The correlation was constructed between the PM10 (or the PM2.5) mass concentrationsand the electrical currents due to particles, which were chargedby the diffusion charger.  相似文献   
38.
While the cathode ray tube (CRT) funnel containing lead could be transported to a smelting facility to recover lead, which could be an available option in domestic, a proper technology to recycle a CRT panel must be developed. Thus, it was suggested that CRT panel glass be used as aggregates of concrete blocks and clay bricks. Samples of blocks and bricks were fabricated with CRT powders and tested to measure their strength and absorption rate to determine their qualities, and environmental soundness was determined by measuring the leaching rate of hazardous metals. For concrete blocks, CRT panel glass powders incorporated as aggregates up to 40 % replacing stone powder was proposed as the proper condition for manufacturing blocks. Around 2 % of CRT panel incorporated into clay brick to substitute Kaoline was suggested to fabricate the best quality of clay brick. Results of leaching test met the criteria with much less concentration of hazardous metals, even lead compound containing in the CRT funnel. To conclude, the use of CRT panel powder after crushing it to the proper size as an aggregate of concrete blocks or clay bricks could be one of the appropriate alternatives to recycle for CRT glass waste being generated drastically in a short term.  相似文献   
39.
Along with the world population increase, meat requirement has been also increasing; thus, massive livestock manure has been released leading to problems due to surplus nutrients. To overcome this situation, we should consider availing some nutrient removal or reuse technology. The commonest way to recover resources from livestock manure is by producing liquid fertilizer and compost. However, some technologies are required to make it easier and safer for transportation and handling of manure fertilizer due to various problems such as poor fertilization quality with low maturity, emission of odor, nutrient loss, and disharmony due to fluctuating seasonal and regional supplies and demands. In this study, available technologies for resource recovery from animal wastes were introduced with economic benefits, and an integrated system was proposed including energy flow. The system consisted of anaerobic digestion or microbial fuel cell, struvite precipitation for P recovery, nitrogen enrichment by mechanical vapor compression distillation, and incineration processes (optional). Consequently, the energy output from the system could be sufficient for operating the entire system without the need for extra energy input.  相似文献   
40.
In this study, we propose a process making calcium carbonate and calcium sulfate and recovering absorbent using ammonia absorbent, carbon dioxide, and industrial waste. The main objective of this study is to confirm the possibility of carbon capture and utilization based on waste materials. We assumed desulfurization gypsum and construction waste (ready mixed concrete washing water, waste concrete, etc.) are CaSO4, Ca(OH)2, respectively. And concentration of simulated carbon dioxide gas was 15 vol% similar to flue gas. Calcium carbonate was produced by combination reaction between ionic CO2 in absorbent and metal ion in the solid waste. Experiments were conducted at normal temperature and pressure. Furthermore, the generated products were characterized by X-ray diffraction, and scanning electron microscope.  相似文献   
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