scholarly journals Scratch Properties of Clear Coat for Automotive Coating Comprising Molecular Necklace Crosslinkers with Silane Functional Groups for Various Environmental Factors

Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3933
Author(s):  
Sung Wook Moon ◽  
Jiae Seo ◽  
Ji-Hun Seo ◽  
Byoung-Ho Choi
Keyword(s):  
Environmental Factors ◽  
Functional Groups ◽  
Outer Layer ◽  
Environmental Conditions ◽  
Critical Loads ◽  
Clear Coat ◽  
Automotive Coatings ◽  
Clear Coating ◽  
Automotive Coating ◽  
Scratch Tests

Automotive coatings, which comprise multiple layers, i.e., primer, base coating, and clear coat layers, are exposed to various environmental conditions that pose various types of damages to them. In particular, the outer layer of the automotive coating, i.e., the clear coat, is affected significantly by such damages. Therefore, a reliable and durable clear coat must be developed to improve the appearance of automobiles. In this study, a new clear coat based on an acrylic-based clear coat modified using polyrotaxane crosslinkers, which are necklace-shaped supramolecules composed of ring-shaped host molecules, is developed and characterized. The effects of polyrotaxane and silane on the scratch properties and mechanisms of the clear coating are analyzed. It is observed that the critical loads of the clear coat from scratch tests can be improved by adding optimal molecular necklace crosslinkers comprising silane functional groups. The improvement in the scratch properties of the modified acrylic-based clear coat may be attributed to the crosslinking characteristics and dynamic molecular movements of the polyrotaxane. In addition, the effects of environmental factors on the scratch characteristics of the modified acrylic-based clear coat are investigated by addressing the scratch durability of the clear coat.

scholarly journals Phytoplankton functional groups indicators of environmental conditions in floodplain rivers and lakes of the Paraná Basin

2017 ◽  
Vol 29 (0) ◽  
Author(s):  
Barbara Furrigo Zanco ◽  
Alfonso Pineda ◽  
Jascieli Carla Bortolini ◽  
Susicley Jati ◽  
Luzia Cleide Rodrigues
Keyword(s):  
Environmental Factors ◽  
Functional Groups ◽  
Environmental Conditions ◽  
Trophic State ◽  
Phytoplankton Community ◽  
Paraná River ◽  
Parana River ◽  
Phytoplankton Functional Groups ◽  
Rivers And Lakes ◽  
Floodplain Rivers

Abstract Aim: The objective of this study was to evaluate the efficacy of phytoplankton functional groups as indicators of environmental conditions in floodplain rivers and lakes with different trophic state and connectivity degree to the Paraná River. Phytoplankton functional groups (FGs) cluster sensitive species to environmental variation and can be an alternative for environmental monitoring. Methods Samples were performed quarterly from 2010 to 2013 in the Ivinhema, Paraná and Baia Rivers and in three lakes permanently connected to each river. Results 419 taxa were identified, and those taxa that had values greater than 5% of the total biovolume were classified into FGs (P, C, A, B, MP, H1, W1, J, TD, LO, and N). The lakes presented higher biovolume and were more productive than rivers, especially in the dry periods. The rivers presented light limitation and low phytoplankton development. The FG LO was an indicator in rainy seasons. Both rivers and lakes were mostly oligotrophic. We registered FG indicators only for the lakes (A, B, C, E, LO, P, and W1) and mesotrophic environments (A, B, C, E, J, LO, and P). Conclusion The FGs reflected the seasonal variation and the trophic state of environments in the upper Paraná River floodplain, mainly in the lentic environments. The species-environment relationship (FGs as indicators) was clearer in the lakes, probably because of the longer water retention that allows evidencing the response of the phytoplankton community to environmental factors. On the other hand, the absence of FGs as indicators in the rivers could be due to the high water flow that promotes dispersal stochasticity and masks the relationship between the environmental factors and the phytoplankton community. Thus, phytoplankton FGs proved to be a viable tool to evaluate the environmental conditions in a floodplain.

scholarly journals Regional environmental controllers influence continental scale soil carbon stocks and future carbon dynamics

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daniel Ruiz Potma Gonçalves ◽  
Umakant Mishra ◽  
Skye Wills ◽  
Sagar Gautam
Keyword(s):  
Environmental Factors ◽  
Land Cover ◽  
Environmental Conditions ◽  
Climate Feedback ◽  
Soil Types ◽  
Climatic Data ◽  
Earth System ◽  
Land Cover Types ◽  
Continental Scale ◽  
Soc Stocks

AbstractUnderstanding the influence of environmental factors on soil organic carbon (SOC) is critical for quantifying and reducing the uncertainty in carbon climate feedback projections under changing environmental conditions. We explored the effect of climatic variables, land cover types, topographic attributes, soil types and bedrock geology on SOC stocks of top 1 m depth across conterminous United States (US) ecoregions. Using 4559 soil profile observations and high-resolution data of environmental factors, we identified dominant environmental controllers of SOC stocks in 21 US ecoregions using geographically weighted regression. We used projected climatic data of SSP126 and SSP585 scenarios from GFDL-ESM 4 Earth System Model of Coupled Model Intercomparison Project phase 6 to predict SOC stock changes across continental US between 2030 and 2100. Both baseline and predicted changes in SOC stocks were compared with SOC stocks represented in GFDL-ESM4 projections. Among 56 environmental predictors, we found 12 as dominant controllers across all ecoregions. The adjusted geospatial model with the 12 environmental controllers showed an R2 of 0.48 in testing dataset. Higher precipitation and lower temperatures were associated with higher levels of SOC stocks in majority of ecoregions. Changes in land cover types (vegetation properties) was important in drier ecosystem as North American deserts, whereas soil types and topography were more important in American prairies. Wetlands of the Everglades was highly sensitive to projected temperature changes. The SOC stocks did not change under SSP126 until 2100, however SOC stocks decreased up to 21% under SSP585. Our results, based on environmental controllers of SOC stocks, help to predict impacts of changing environmental conditions on SOC stocks more reliably and may reduce uncertainties found in both, geospatial and Earth System Models. In addition, the description of different environmental controllers for US ecoregions can help to describe the scope and importance of global and local models.

Emerging investigator series: interacting effects of environmental factors on Daphnia magna removal of Escherichia coli from wastewater

2021 ◽  
Vol 7 (4) ◽  
pp. 726-738
Author(s):  
Seyyed M. H. Abtahi ◽  
Ojaswi Aryal ◽  
Niveen S. Ismail
Keyword(s):  
Escherichia Coli ◽  
Environmental Factors ◽  
Daphnia Magna ◽  
Environmental Conditions ◽  
E Coli

Zooplankton can significantly impact E. coli inactivation in wastewater, but inactivation rates are dependent on environmental conditions.

scholarly journals REDUCING THE INFLUENCE OF ENVIRONMENTAL FACTORS ON THE BENDING DEFORMATION OF CURED CARBON FIBER BY MICROWAVE PROCESSING

2021 ◽  
pp. 56-58
Author(s):  
I. V. Zlobina
Keyword(s):  
Electromagnetic Field ◽  
Composite Materials ◽  
Carbon Fiber ◽  
Environmental Factors ◽  
Flux Density ◽  
Environmental Conditions ◽  
Climatic Factors ◽  
Transverse Load ◽  
Bending Deformation ◽  
Energy Flux Density

The article discusses the results of a study of bending deformation and creep under transverse load of cured polymer composite materials (PCM), which were located for 8 months in full-scale environmental conditions in Saratov. It was found that being under the influence of natural climatic factors for the specified time leads to an increase in the bending deformation of samples from 13,5 to 25,4%, depending on the load. Processing in a microwave electromagnetic field with a frequency of 2450 MHz with an energy flux density of (17-18) x10 mW / cm for 2 minutes reduces bending deformation by (9-18)%, and creep - up to 4 times.

In vitro studies on the induction of sporogenous tissue on leaves of cinnamon fern. I. Environmental factors

1972 ◽  
Vol 50 (12) ◽  
pp. 2673-2682 ◽  
Author(s):  
William H. Harvey ◽  
James D. Caponetti
Keyword(s):  
Environmental Factors ◽  
Light Intensity ◽  
Environmental Conditions ◽  
Light Exposure ◽  
Progressive Increase ◽  
Light Phase ◽  
Sporogenous Tissue ◽  
Light Darkness

Intact, set III, cinnamon fern cataphyll and frond primordia, which were shown to have no predisposition to fertility in situ, produced sporangia when excised and cultured under sterile conditions in Knudson's medium supplemented with various levels of sucrose and maintained on 11 different regimens of light, darkness, and temperature for 10 weeks. Increasing levels of sucrose resulted in increased fertility under all environmental conditions, but the highest percentage of fertility was obtained under conditions of continuous dark at 26 °C. As the length of the light phase of the photoperiods decreased, a progressive increase in induction of fertile leaves was observed, suggesting that periods of long light exposure are inhibitory to the initiation of sporangia. Conversely, as the light intensity was increased, an inhibition of sporophyll differentiation occurred. Sporangia excised from dark-induced sporophylls and cultured in the light produced viable spores which germinated yielding haploid gametophytes that ultimately produced sporophytes.

Bioeroding sponge assemblages: the importance of substrate availability and sediment

2018 ◽  
Vol 99 (2) ◽  
pp. 343-358 ◽  
Author(s):  
Joseph Marlow ◽  
Christine H.L. Schönberg ◽  
Simon K. Davy ◽  
Abdul Haris ◽  
Jamaluddin Jompa ◽  
...  
Keyword(s):  
Coral Reef ◽  
Environmental Factors ◽  
Spatial Variation ◽  
Environmental Conditions ◽  
Sponge Species ◽  
Coral Mortality ◽  
Substrate Availability ◽  
Abiotic Conditions ◽  
Assemblage Composition ◽  
Reef Health

Despite global deterioration of coral reef health, not all reef-associated organisms are in decline. Bioeroding sponges are thought to be largely resistant to the factors that stress and kill corals, and are increasing in abundance on many reefs. However, there is a paucity of information on how environmental factors influence spatial variation in the distribution of these sponges, and how they might be affected by different stressors. We aimed to identify the factors that explained differences in bioeroding sponge abundance and assemblage composition, and to determine whether bioeroding sponges benefit from the same environmental conditions that can contribute towards coral mortality. Abundance surveys were conducted in the Wakatobi region of Indonesia on reefs characterized by different biotic and abiotic conditions. Bioeroding sponges occupied an average of 8.9% of available dead substrate and variation in abundance and assemblage composition was primarily attributed to differences in the availability of dead substrate. Our results imply that if dead substrate availability increases as a consequence of coral mortality, bioeroding sponge abundance is also likely to increase. However, bioeroding sponge abundance was lowest on a sedimented reef, despite abundant dead substrate. This suggests that not all forms of coral mortality will benefit all bioeroding sponge species, and sediment-degraded reefs are likely to be dominated by a few resilient bioeroding sponge species. Overall, we demonstrate the importance of understanding the drivers of bioeroding sponge abundance and assemblage composition in order to predict possible impacts of different stressors on reefs communities.

Modern problems of regionalization of territories and human adaptation in regions with extreme natural and climatic conditions

2021 ◽  
Author(s):  
A.L. Maksimov
Keyword(s):  
Environmental Factors ◽  
Environmental Conditions ◽  
Allostatic Load ◽  
Climatic Conditions ◽  
Extreme Conditions ◽  
Human Adaptation ◽  
Nonspecific Resistance ◽  
Key Words Adaptation ◽  
High Level ◽  
Selection Of

The paper considers modern approaches to the zoning of territories and the selection of people for life in extreme environmental conditions, taking into account modern geopolitical challenges. It is shown that it is possible, based on the allostasis concept, to conduct not only the selection of persons with a high level of nonspecific resistance, but also to quantify the degree of extremity of environmental factors using the standard represpiration test. Key words: adaptation, extreme conditions, selection, hypoxia, cold, rerespiration, allostatic load.

scholarly journals Diversity and Preference of Habitat Violin Crabs in Mangrove Areas Pancer Cengkrong Trenggalek Regency, East Java

2019 ◽  
Vol 17 (1) ◽  
pp. 82
Author(s):  
Niken Sawitri ◽  
Sunarto Sunarto ◽  
Prabang Setyono
Keyword(s):  
Environmental Factors ◽  
Natural Resource ◽  
Environmental Conditions ◽  
Diversity Index ◽  
Aquatic Biota ◽  
Vegetation Density ◽  
Mangrove Area ◽  
Living Things ◽  
Mangrove Vegetation ◽  
Mangrove Roots

ABSTRAKMangrove merupakan suatu ekosistem yang khas dan menjadi sumber daya alam yang sangat berperan penting dalam keberlangsungan makhluk hidup. Salah satunya melibatkan faktor lingkungan perairan mangrove yang dapat menyebabkan kesuburan diperairan sehingga banyak ditemukannya biota air yang hidup di kawasan tersebut, salah satunya adalah kepiting biola. Tujuan penelitian ini ialah untuk mengetahui keanekaragaman kepiting biola yang hidup di kawasan mangrove Pancer. Penelitian ini dilaksanakan pada bulan November-Desember 2017 di mangrove Pancer Cengkrong Kabupaten Trenggalek, Jawa timur. Dari penelitian ini ditemukan 7 jenis kepiting biola, yaitu Uca rosea, U.annulipes, U.forcipata, U.crassipes, U.vomeris, U.lactea dan U.paradussumieri. Tujuh spesies kepiting biola menempati beberapa tipe habitat yaitu, substart berpasir, substrat berlumpur, berlumpur dan berpasir, sekitar akar mangrove, serta akar mangrove yang berpasir. Indeks keanekaragaman kepiting biola di kawasan mangrove bagian stasiun 1 (3,4) tergolong tinggi, stasiun 2 (1,8), dan stasiun 3 (1,3) tergolong sedang. Kondisi lingkungan yang ada di seluruh stasiun relatif baik untuk kehidupan vegetasi mangrove dan kepiting biola. Kondisi tersebut ialah pH 7-9, suhu 27-31, salinitas 21,6 ppt, oksigen terlarut 5,5-8 mg/L, dan substrat lumpur berpasir. Kesimpulan dari penelitian ini ialah kerapatan vegetasi mangrove sangat berkaitan dengan kelimpahan jenis (kepadatan) kepiting biola serta banyaknya spesies di dalam suatu komunitas akan mempengaruhi keanekaragaman ekosistem yang ada di kawasan mangrove Pancer. Kata kunci : Kepiting biola, mangrove, keanekaragaman, TrenggalekABSTRACTMangroves are a unique ecosystem and become a natural resource that plays an important role in the survival of living things. One of them involves the environmental factors of mangrove waters that can cause fertility in the waters so that many aquatic biota are found in the area, one of which is a violin crab. The purpose of this study was to determine the diversity of violin crabs that live in the Pancer mangrove area. This research was carried out in November to Desember 2017 in the mangrove Pancer Cengkrong Trenggalek Regency, East Java. The results found seven types of violin crabs, namely Uca rosea, U.annulipes, U.forcipata, U.crassipes, U.vomeris, U.lactea and U.paradussumieri. seven species of violin crabs occupy several types of habitats, namely sandy substrates, muddy substrate, muddy and sandy, around mangrove roots, and sandy mangrove roots. Diversity index of violin crabs in the station 1 (3,4) mangrove area classified as high, station 2 (1,8), and station 2 (1,3) classified as medium. The environmental conditions in al stations are relatively good for the life of mangrove vegetation and violin crabs. These conditions are pH 7-9, temperature 27-32, salinity 21.6 ppt, dissolved oxygen 5.5-8 mg/L, and sandy mud substrate. The conclusion of this study is that mangrove vegetation density is closely related to the abundance of species (density) of violin crabs and the number of species in a community will affect the diversity of ecosystems in the Pancer mangrove area.Keywords: Violin Crab, Mangrove, Diversity, Trenggalek

scholarly journals Effects of environmental conditions and space on species turnover for three plant functional groups in Brazilian savannas

2019 ◽  
Vol 12 (6) ◽  
pp. 1047-1058 ◽  
Author(s):  
Hélio Menegat ◽  
Divino Vicente Silvério ◽  
Henrique A Mews ◽  
Guarino R Colli ◽  
Ana Clara Abadia ◽  
...  
Keyword(s):  
Functional Groups ◽  
Environmental Conditions ◽  
Environmental Gradients ◽  
Species Turnover ◽  
Geographic Distance ◽  
Floristic Composition ◽  
Environmental Variation ◽  
Variance Partitioning ◽  
Plant Functional Groups ◽  
Palm Species

Abstract Aims Different plant functional groups display diverging responses to the same environmental gradients. Here, we assess the effects of environmental and spatial predictors on species turnover of three functional groups of Brazilian savannas (Cerrado) plants—trees, palms and lianas—across the transition zone between the Cerrado and Amazon biomes in central Brazil. Methods We used edaphic, climatic and plant composition data from nine one-hectare plots to assess the effects of the environment and space on species turnover using a Redundancy Analysis and Generalized Dissimilarity Modeling (GDM), associated with variance partitioning. Important Findings We recorded 167 tree species, 5 palms and 4 liana species. Environmental variation was most important in explaining species turnover, relative to geographic distance, but the best predictors differed between functional groups: geographic distance and silt for lianas; silt for palms; geographic distance, temperature and elevation for trees. Geographic distances alone exerted little influence over species turnover for the three functional groups. The pure environmental variation explained most of the liana and palm turnover, while tree turnover was largely explained by the shared spatial and environmental contribution. The effects of geographic distance upon species turnover leveled off at about 300 km for trees, and 200 km for lianas, whereas they were unimportant for palm species turnover. Our results indicate that environmental factors that determine floristic composition and species turnover differ substantially between plant functional groups in savannas. Therefore, we recommend that studies that aim to investigate the role of environmental conditions in determining plant species turnover should examine plant functional groups separately.

Distribution of batoid demersal assemblages on the continental shelf of the Gulf of Tehuantepec

2019 ◽  
Vol 70 (10) ◽  
pp. 1445 ◽  
Author(s):  
Ana María Torres-Huerta ◽  
Ramón Andrés López-Pérez ◽  
Margarito Tapia-García ◽  
Adolfo Gracía
Keyword(s):  
Environmental Factors ◽  
Surface Temperature ◽  
Environmental Conditions ◽  
Hierarchical Cluster ◽  
Comparison Method ◽  
Sea Surface ◽  
Habitat Characteristics ◽  
Small Species ◽  
Gulf Of Tehuantepec ◽  
The Relationship

Information on the relationship between batoid demersal assemblages and environmental factors is scarce. We captured a total of 23414 batoids belonging to 16 species with bottom trawls at 243 sampling stations in the Gulf of Tehuantepec, Mexico. The species Urotrygon rogersi, Urotrygon chilensis and Narcine vermiculatus represented 70.1% of the abundance and 46.3% of the biomass. Five batoid assemblages were identified using hierarchical cluster and similarity profile analyses. Four assemblages were located at depths less than 40m and one assemblage was located at depths between 40 and 62m. The main batoid group was located in front of the most important lagoon complexes. The abundance biomass comparison method indicated that small species were dominant in terms of abundance in most assemblages. The set of environmental conditions and habitat characteristics (longitude, depth and sea surface temperature) present in the Gulf of Tehuantepec predicted important changes in the batoid community and affected its spatiotemporal distribution pattern.

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