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Marzena Malińska Joanna Bugajska Joanna Kamińska Anna Jędryka-Góral 《International journal of occupational safety and ergonomics》2013,19(3):443-449
AbstractAim. The aim of this study was to evaluate working conditions with a notebook computer (notebook) as a potential cause of musculoskeletal disorders. Material and methods. The study had 2 stages. The first one was a questionnaire survey among 300 notebook users. The next stage was an expert analysis of 53 randomly selected workstations. The questionnaire survey included questions about the participants, their working conditions, work organization and also duration of work with a notebook. Results and conclusions. The results of the research showed that most examined operators used a notebook as a basic working tool. The most important irregularities included an unadjustable working surface, unadjustable height of the seat pan and backrest, unadjustable height and distance between the armrests and no additional ergonomic devices (external keyboard, docking station, notebook stand or footstool). 相似文献
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对U型截面弯曲件失稳起皱问题进行了研究,通过板材成形性能实验及起皱模拟实验,对失稳起皱原因进行了分析,为类似的异型截面弯曲件起皱的预防提供了可行的实验分析方法。 相似文献
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Based on the consumer questionnaires of the three traditional retailing centers,Qianmen,Wangfujing and Xidan in Beijing,this article analyzes the present features of consumer composition in the three retailing centers.What is more,the evolution course and function transition of traditional retailing centers is revealed based on the changing of consumer composition in different times.Lastly,the renewal method and development trends of traditional retailing centers are discussed based on the evaluation results in consumers' perspective. 相似文献
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Journal of Material Cycles and Waste Management - Activated carbon (AC) was prepared from wastewater treatment sludge by KOH activation and then used for the adsorptive purification of crude... 相似文献
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Kaushik Himanshu Ranjan Rashmi Ahmad Rakhshan Kumar Alok Prashant Kumar Nitish Ranjan Rajesh Kumar 《Environmental science and pollution research international》2021,28(15):18686-18701
Environmental Science and Pollution Research - The concentration of trace metals Mn, Pb, Ni, Zn, and Cu in the core sediment from Kabar Tal wetland was analyzed to understand the level of... 相似文献
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Hipólito Amanda Caretta Talita de Oliveira Silveira Victória Akemi Itakura Bersaneti Gabrielly Terassi Mali Suzana Celligoi Maria Antonia Pedrine Colabone 《Journal of Polymers and the Environment》2021,29(10):3199-3209
Journal of Polymers and the Environment - Sophorolipids are glycolipid biosurfactants produced by the yeast Starmerella bombicola. They have great potential for application in the food industry due... 相似文献
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Assessing the impact of the Indian Ocean tsunami on households: a modified domestic assets index approach 总被引:1,自引:0,他引:1
Sudha Arlikatti Walter Gillis Peacock Carla S. Prater Himanshu Grover Arul S. Gnana Sekar 《Disasters》2010,34(3):705-731
This paper offers a potential measurement solution for assessing disaster impacts and subsequent recovery at the household level by using a modified domestic assets index (MDAI) approach. Assessment of the utility of the domestic assets index first proposed by Bates, Killian and Peacock (1984) has been confined to earthquake areas in the Americas and southern Europe. This paper modifies and extends the approach to the Indian sub‐continent and to coastal surge hazards utilizing data collected from 1,000 households impacted by the Indian Ocean tsunami (2004) in the Nagapattinam district of south‐eastern India. The analyses suggest that the MDAI scale is a reliable and valid measure of household living conditions and is useful in assessing disaster impacts and tracking recovery efforts over time. It can facilitate longitudinal studies, encourage cross‐cultural, cross‐national comparisons of disaster impacts and inform national and international donors of the itemized monetary losses from disasters at the household level. 相似文献
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Gupta Himanshu Kumar Harish Gehlaut Avneesh Kumar Singh Satish Kumar Gaur Ankur Sachan Sadhana Park Jin-Won 《Journal of Material Cycles and Waste Management》2022,24(2):569-581
Journal of Material Cycles and Waste Management - A great deal of focus has been given to finding a bio-composite film to substitute petroleum-based synthetic plastic in recent years. Many animals... 相似文献
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Antić MP Jovancićević BS Ilić M Vrvić MM Schwarzbauer J 《Environmental science and pollution research international》2006,13(5):320-327
Background, Aims and Scope It is well known that the composition of petroleum or some of its processing products changes in the environment mostly under
the influence of microorganisms. A series of experiments was conducted in order to define the optimum conditions for an efficient
biodegradation of petroleum pollutant, or bioremediation of different segments of the environment. The aim of these investigations
was to show to what extent the hydrocarbons of a petroleum pollutant are degraded by microbial cultures which were isolated
as dominant microorganisms from a surface water of a wastewater canal of an oil refinery and a nitrogen plant. Biodegradation
experiments were conducted on one paraffinic, and one naphthenic type of petroleum during a three month period under aerobic
conditions, varying the following parameters: Inorganic (Kp) or an organic medium (Bh) with or without exposition to light.
Methods Microorganisms were analyzed in a surface water sample from a canal (Pančevo, Serbia), into which wastewater from an oil
refinery and a nitrogen plant is released. The consortia of microorganisms were isolated from the water sample (most abundant
species: Phormidium foveolarum - filamentous Cyanobacteria, blue-green algae and Achanthes minutissima, diatoms, algae). The
simulation experiments of biodegradation were conducted with the biomass suspension and crude oils Sirakovo (Sir, paraffinic
type) and Velebit (Ve, naphthenic type). After a three month period, organic substance was extracted by means of chloroform.
In the extracts, the content of saturated hydrocarbons, aromatic hydrocarbons, alcohols and fatty acids was determined (the
group composition). n-Alkanes and isoprenoid aliphatic alkanes, pristane and phytane, in the aliphatic fractions, were analyzed
using gas chromatography (GC). Total isoprenoid aliphatic alkanes and polycyclic alkanes of sterane and triterpane types were
analyzed by GC-MS.
Results and discussion. Paraffinic type petroleums have a significant loss of saturated hydrocarbons. For naphthenic type petroleum,
such a trend has not been observed. The most intensive degradation of n-alkanes and isoprenoid aliphatic alkanes (in paraffinic
oil) and isoprenoids (in naphthenic oil) was observed using the inorganic medium Kp in the light; the microbial conversion
is somewhat lower with Kp in the dark; with organic medium Bh in the light the degradation is of low intensity; with the same
medium in the dark the degradation is hardly to be seen. Steranes and triterpanes were not affected by microbial degradation
under the conditions used in our experiments. Obviously, the petroleum biodegradation was restricted to the acyclic aliphatics
(n-alkanes and isoprenoids).
Conclusion Phormidium foveolarum (filamentous Cyanobacteria - blue-green algae) and Achanthes minutissima (diatoms, algae), microbial
cultures isolated as dominant algae from a surface water in a wastewater canal of an oil refinery and a nitrogen plant, have
degradable effects dominantly involving petroleum hydocarbons. Petroleum microbiological degradation is more intensive when
inorganic medium (in the light) is applied. Having in mind that the inorganic pollutants have been released into the canal
as well, this medium reflects more the natural environmental conditions. Polycyclic alkanes of sterane and triterpane type,
in spite of the fact that these compounds could be degraded, have remained unchanged regarding abundance and distribution.
Since this is the case even for naphthenic type petroleum (which is depleted in n-alkanes), it can be concluded that the biodegradation
of petroleum type pollutants, under natural conditions, will be restrained to the n-alkane and isoprenoid degradation.
Recommendation and Outlook Performed experiments and simulations of petroleum microbiological degradation may serve for the prediction of the fate of
petroleum type pollutants, as well as for definition of conditions for bioremediation of some environmental segments. 相似文献