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The oil palm industry is one of the important sectors in Malaysia. The growth and development of this industry shows that Malaysia is the world second-largest oil palm producers. However, in the fresh fruit bunch (FFB) harvesting process, the harvesters are exposed to many types of work-related musculoskeletal disorders (WMSDs). The FFB harvesters tend to develop WMSDs especially the shoulders and trunk. Hence, it is important to identify the exposure levels, awkward postures and the reaction forces of muscle activity based on the posture and movement of the harvesters when using pole, chisel and loading spike during the harvesting process. The objective of this study was to investigate the effect of the design of oil palm FFB harvesting tools on WMSDs of the upper body. Rapid Upper Limb Analysis (RULA) was used to investigate and assess the exposure level on the harvester body during the harvesting process. The assessment showed that the shoulders and trunk have high exposure level and undergo awkward posture. Human Musculoskeletal Model Analysis (HMMA) was used to identify the reaction force exerted on the muscle during the FFB harvesting process. In this study, 4 muscles were analysed including Triceps, Biceps, Erector Spinae and Psoas Major. The highest reaction force of 16.36 N was found on the left triceps when handling a loading spike. In conclusion, it is important to address the risks by reviewing all possible aspects that contribute to the WMSDs and interventions on the tool design, task and working shifts may be required.  相似文献   
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探索了中温条件下不同粒径聚对苯二甲酸乙二醇酯(PET)微塑料(30 μm和250 μm)在0、0.45、1.44、2.88 mg/g总固体(TS)的添加量下,对剩余污泥和厨余垃圾厌氧共消化过程中每日甲烷产量、累计甲烷产量、溶解性化学需氧量、氨氮、挥发性脂肪酸以及微生物群落结构的影响。结果表明,PET微塑料会抑制甲烷产量、增加氨抑制、酸抑制风险。在微塑料投加量为2.88 mg/g TS时,累计甲烷产量分别下降了54.49 %(30 μm) 和 49.58 %(250 μm)。微生物结果表明:添加微塑料后细菌的多样性增加,古菌的多样性降低。在共消化过程,微塑料抑制了产酸菌PrevotellaProteiniphilum的丰度,同时也抑制了产甲烷菌Methanosaeta的丰度,减弱乙酸产甲烷的途径。相关性分析表明,微塑料的粒径与Euryarchaetota呈显著正相关(r=0.945、p<0.01)。微塑料粒径越小,对产甲烷菌丰度抑制越明显,与其他细菌相比,产甲烷菌对微塑料更为敏感。  相似文献   
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Industrial parks have become the effective strategies for government to promote sustainable economic development due to the following advantages: shared infrastructure and concentrated industrial activities within planned areas. However, due to intensive energy consumption and dependence on fossil fuels, industrial parks have become the main areas for greenhouse gas emissions. Therefore, it is critical to quantify their carbon footprints so that appropriate emission reduction policies can be raised. The objective of this paper is to seek an appropriate method on evaluating the carbon footprint of one industrial park. The tiered hybrid LCA method was selected due to its advantages over other methods. Shenyang Economic and Technological Development Zone (SETDZ), a typical comprehensive industrial park in China, was chosen as a case study park. The results show that the total life cycle carbon footprint of SETDZ was 15.29 Mt, including 6.81 Mt onsite (direct) carbon footprint, 8.47 Mt upstream carbon footprint, and only 3201 t downstream carbon footprint. Analysis from industrial sector perspectives shows that chemical industry and manufacture of general purpose machinery and special purposes machinery sector were the two largest sectors for life cycle carbon footprint. Such a sector analysis may be useful for investigation of appropriate emission reduction policies.  相似文献   
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《Materials Letters》2003,57(5-6):1051-1055
Semiconductor cadmium selenide particles together with europium ions were incorporated into the silica matrix using sol–gel method. Here, the effect of nanocrystals on the absorption and fluorescence features of europium ions is discussed. The fluorescence spectra reveal that the intensity of characteristic emission of europium increases considerably in the presence of CdSe particles. This phenomenon can be explained as due to the energy transfer resulting from electron–hole recombination in the CdSe to the rare earth ion. These zero-dimensional materials, along with the effect of matrix incorporating europium ions, are found to have increased the optical gain.  相似文献   
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As an example of the importance and the potential of in situ structure/function studies, nitrifying aggregates from different zones of a lab-scale fluidised bed reactor were analysed by microelectrode measurements of O2 NH4+, NO2, and NO3 and in situ hybridisation targeting the 16S rRNA of the nitrifying bacteria. A shift trom an ammonia oxidising to a nitrite oxidising community is present along the reactor. In the single aggregates an active nitrifying shell of about 100 gm could be related to the maximum abundance of nitrifiers in this zone. Interestingly, the main actors in this system are not representatives of the well-described genera Nitrosomonas and Nitrobacter but some other ammonia oxidisers from the beta subclass of Protcobacteria and a thus far unknown nitrite oxidising population.  相似文献   
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In Europe, CO2 emissions from the electric power sector and energy intensive industries are capped under a cap-and-trade system (i.e., the EU ETS). When other indirect measures are taken to impact emissions in a specific sector under the cap (such as a push for renewables in the electric power sector), this has implications on the overall allowance price, and on CO2 emissions both from this specific sector and the other sectors under the cap. The central contribution of this paper is the derivation of impact curves, which describe these interactions, i.e., the impact on allowance price and the shift of emissions across sectors. From a set of detailed simulations of the electric power system operation, a so-called “emission plane” is obtained, from which impact curves can be derived. Focus is on interactions between CO2 abatement through fuel switching and measures affecting the residual electricity demand (such as deployment of renewables) in the electric power sector, as well as on interactions with other sectors, both in a short-term framework. A case study for Central-Western Europe is presented. The analysis reveals a substantial impact of renewables on CO2 emissions, and hence on emissions shifts across sectors and/or on the CO2 price.  相似文献   
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For the period September 1984 to November 1985 water samples from the aquatic system of Ioannina basin were analyzed every second month for organochlorine and triazines pesticides. The detected compounds were found to follow a seasonal pattern, with an increment during summer followed by a decrease during winter and an increase again during late spring. This pattern was apparent for Ioannina lake as well as for the Kalamas river connected to it through the Lapsista's canal and tunnel. The results are discussed in terms of the amounts of the detected pesticides used for farming in the vicinity of the Ioannina basin and the seasonal rainfall.  相似文献   
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