This paper proposes a methodology for using mobile telephone-based sensor data for detecting spatial and temporal differences in everyday activities in cities. Mobile telephone-based sensor data has ...great applicability in developing urban monitoring tools and smart city solutions. The paper outlines methods for delineating indicator points of temporal events referenced as 'midnight', 'morning start', 'midday', and 'duration of day', which represent the mobile telephone usage of residents (what we call social time) rather than solar or standard time. Density maps by time quartiles were also utilized to test the versatility of this methodology and to analyze the spatial differences in cities. The methodology was tested with data from cities of Harbin (China), Paris (France), and Tallinn (Estonia). Results show that the developed methods have potential for measuring the distribution of temporal activities in cities and monitoring urban changes with georeferenced mobile phone data.
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2.
Changes in European spring phenology Ahas, R.; Aasa, A.; Menzel, A. ...
International journal of climatology,
30 November 2002, Volume:
22, Issue:
14
Journal Article
The objective of this study is to create an ultra-thin palladium foil with a molecular dynamic (MD) simulation technique on a copper substrate surface. The layer formed onto the surface consists of a ...singular 3D palladium (Pd) nanoparticle structure which, by the cold gas dynamic spray (CGDS) technique, is especially incorporated into the low-cost copper substrate. Pd and Cu have been chosen for their possible hydrogen separation technology applications. The nanoparticles were deposited to the substrate surface with an initial velocity ranging from 500 to 1500 m/s. The particle radius was 1 to 4 nm and an angle of impact of 90° at room temperature of 300 K, in order to evaluate changes in the conduct of deformation caused by effects of size. The deformation mechanisms study revealed that the particle and substrate interface is subject to the interfacial jet formation and adiabatic softening resulting in a uniform layering. However, shear instabilities at high impact speeds were confirmed by the evolution of von Mises shear strain, temperature evolution and plastic strain. The results of this study can be used to further our existing knowledge in the complex spraying processes of cold gas dynamic spray technology.
The concerns of food safety are rising in developing countries such as South Africa as a result of heavy metal contamination of culinary herbs and spices. Spices and herbs are used for therapeutic ...purposes as well as flavoring and coloring food. Heavy metals in spices represent significant health risks due to their high toxicity in high quantities. A total of 20 spices samples were purchased from different registered shops, for heavy metals analysis. The samples were prepared, digested, and analyzed with an inductively coupled plasma mass spectrometer (ICP-MS). To ensure the method's accuracy, Polish Certified Reference Mixed Polish Herbs (INCT-MPH-2) from the Food and Drugs Control Center, Poland, was analyzed. The concentrations of Fe (32.22 ± 1.22–131.1 ± 3.26 mg/kg), As (ND to 0.12 ± 0.04 mg/kg), Cr (0.08 ± 0.01–3.2 ± 0.09 mg/kg), Pb (N.D - 0.21 ± 0.02 mg/kg) and Cd (ND to 0.14 ± 0.08 mg/kg) mg/kg were measured. The results revealed that the concentrations of Cr in all spice samples tested were much higher than the Maximum permissible limit (MPL) values. All spices in this study had THQ and HI values less than one, indicating that consumers will experience no potential health hazards from consuming specific metals through spices. However, continual scrutiny should be maintained.
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•Spices are the dried parts of plants used historically to enhance food's flavor, color, and aroma. .•The species samples were digested using a microwave acid-assisted system.•5 heavy metals were determined simultaneously by ICP-MS.•ICP-MS demonstrated high sensitivity and confirmatory capacity needed for determining heavy metals.•The validated method was applied successfully to spice samples from South Africa.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We took daily near-surface air temperature data from across Europe to calculate a series of 12 biologically relevant temperature summaries. Mean values for two 30 yr periods, 1941–1970 and 1971–2000, ...were compared and rates of change calculated for those meteorological stations with sufficient data. We generated contour maps for these temperature summaries for both 30 yr periods and for the difference between them; we believe these are the first such maps for over a century. Change was most pronounced and most consistent in those variables describing the onset of spring. Between 1971 and 2000, the thermal start of the growing season began on average 0.36 d yr⁻¹ earlier and ended 0.10 d yr⁻¹ later, suggesting an 11 d earlier beginning and 3 d later end of the growing season over the 30 yr period. For all but one of the temperature summaries, change has accelerated in recent time; however, change was not uniform across Europe.
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The bibliometric analysis of nanoparticle-suspended biodiesel engine performance research (NSBEPR) has been presented. Publication data on NSBEPR extracted from the Scopus® database from 2009 to 2021 ...were analyzed using VOS viewer®. The network of co-authorship of participating countries and organizations, citation counts of scientific papers and journals, and co-occurrence of author keyword were analyzed to study the research trend, hotspot, temporal distribution, and future direction. With a sum of 260 scientific publications used in this study, the network analysis revealed India (208 articles and 4514 citations) and the University of Malaya (12 articles and 700 citations) were the most productive country and institution, respectively, concerning NSBEPR. The most cited paper and journal were the work of Shaafi and Velraj (2015) and "Fuel" with 208 and 1256 citations, respectively. The utilization of metal oxides (Al
2
O
3
and CeO
2
) as nanoparticles, waste (cooking oil) and edible (soybean) oils as biodiesel feedstocks, biodiesel blend with diesel (at 20%) as fuel, and the investigation of the same in direct ignition diesel engines were observed as the research hotspots. Future research focused on the deployment of magnetic conditioning, green and novel nanoparticles, hybrid and novel biodiesel, hydrogen, spent tire, and plastic oils as fuel additives.
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Recent warming of Northern Hemisphere (NH) land is well documented and typically greater in wintersolidusspring than other seasons. Physical environment responses to warming have been reported, but ...not details of large-area temperate growing season impacts, or consequences for ecosystems and agriculture. To date, hemispheric-scale measurements of biospheric changes have been confined to remote sensing. However, these studies did not provide detailed data needed for many investigations. Here, we show that a suite of modeled and derived measures (produced from daily maximum-minimum temperatures) linking plant development (phenology) with its basic climatic drivers provide a reliable and spatially extensive method for monitoring general impacts of global warming on the start of the growing season. Results are consistent with prior smaller area studies, confirming a nearly universal quicker onset of early spring warmth (spring indices (SI) first leaf date, -1.2 days decadesuperscript -1), late spring warmth (SI first bloom date, -1.0 days decadesuperscript -1; last spring day below 5°C, -1.4 days decadesuperscript -1), and last spring freeze date (-1.5 days decadesuperscript -1) across most temperate NH land regions over the 1955-2002 period. However, dynamics differ among major continental areas with North American first leaf and last freeze date changes displaying a complex spatial relationship. Europe presents a spatial pattern of change, with western continental areas showing last freeze dates getting earlier faster, some central areas having last freeze and first leaf dates progressing at about the same pace, while in portions of Northern and Eastern Europe first leaf dates are getting earlier faster than last freeze dates. Across East Asia last freeze dates are getting earlier faster than first leaf dates.
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