scholarly journals Morphology, Chemical Characterization and Sources of Microplastics in a Coastal City in The Equatorial Zone With Diverse Anthropogenic Activities (Fortaleza City, Brazil)

Author(s):  
Maria E. N. Banegas ◽  
Viviane A. S. Lemos ◽  
Gina L. L. Flores ◽  
Sandra A. Soares ◽  
Johnny Feitosa ◽  
...  

Abstract The aim of the present study was to perform morphological and chemical characterizations of microplastics (MPs) found in seawater samples from the coast of the city of Fortaleza (CE) using Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy and differential scanning calorimetry (DSC). Sampling was performed using a neuston sampler. MPs were separated based on the difference in density. MPs with varied morphologies were found. Fibers and fragments were the most abundant (57% and 36.2%, respectively). FTIR, Raman spectroscopy and DSC confirmed the presence of polyurethane and alkyd resin, polyethylene, polypropylene, polystyrene, polyamide blends, thermoplastic rubber and polyester fibers. Many studies have chemically characterized plastic materials using FTIR, Raman spectroscopy and DSC and common MPs, such as polyethylene, polypropylene, polyamide and polyester, have been characterized. However, characterization becomes more complex when MPs are less common particles, weathered particles and blends of polymers and additives. There is also less information on these types of MPs in commercial polymer databases. Therefore, the MP spectra obtained in this study can serve as a database to compare and characterize common as well as less common, more complex MPs.

Agromet ◽  
2018 ◽  
Vol 32 (1) ◽  
pp. 42
Author(s):  
Ariesta Kusuma Wardhani ◽  
Bregas Budianto ◽  
Yon Sugiarto

Vegetation has a role in reducing CO<sub>2</sub> from anthropogenic activities through photosynthesis. Fuel combustion is one of the activities that greatly contribute to CO<sub>2</sub> emissions. As a city with many destinations, the possibility of CO<sub>2</sub> emissions will increase in Bogor especially on holidays because of motorized vehicle from other cities. This research aims to determine the absorption capability of vegetation in Bogor City in reducing CO<sub>2</sub> emitted from fuel combustion. We analyzed CO<sub>2</sub> data for 2017 by day to obtain traffic levels in the city assuming that people mobility using vehicle was influenced by day. Then we separated CO<sub>2</sub> data into slow and fast photosynthesis rate based on air temperature. We determined the absorption capability of vegetation at daily basis by calculating the difference between the min and the max of CO<sub>2 </sub>concentration divided by the min of CO<sub>2</sub>. Our results showed that the lowest CO<sub>2</sub> level was in Sunday. On that day, the average air temperatur was high indicating the less CO<sub>2</sub> concentration. Our one-way Anova test confirmed this finding. The finding revealed that the absorption capability of vegetation to reduce anthropogenic CO<sub>2</sub> was still limited. To implement Bogor as green city, more vegetations and gardens are needed to balance an increased CO<sub>2</sub>.


Author(s):  
Azhari Amri

Film Unyil puppet comes not just part of the entertainment world that can be enjoyed by people from the side of the story, music, and dialogue. However, there is more value in it which is a manifestation of the creator that can be absorbed into the charge for the benefit of educating the children of Indonesia to the public at large. The Unyil puppet created by the father of Drs. Suyadi is one of the works that are now widely known by the whole people of Indonesia. The process of creating a puppet Unyil done with simple materials and formation of character especially adapted to the realities of the existing rural region. Through this process, this research leads to the design process is fundamentally educational puppet inspired by the creation of Si Unyil puppet. The difference is the inspiring character created in this study is on the characters that exist in urban life, especially the city of Jakarta. Thus the results of this study are the pattern of how to shape the design of products through the creation of the puppet with the approach of urban culture.


Atmosphere ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 614
Author(s):  
Muhammad Faisal ◽  
Zening Wu ◽  
Huiliang Wang ◽  
Zafar Hussain ◽  
Chenyang Shen

Heavy metals in road dust pose a significant threat to human health. This study investigated the concentrations, patterns, and sources of eight hazardous heavy metals (Cr, Ni, Cu, Zn, As, Cd, Pb, and Hg) in the street dust of Zhengzhou city of PR China. Fifty-eight samples of road dust were analyzed based on three methods of risk assessment, i.e., Geo-Accumulation Index (Igeo), Potential Ecological Risk Assessment (RI), and Nemerow Synthetic Pollution Index (PIN). The results exhibited higher concentrations of Hg and Cd 14 and 7 times higher than their background values, respectively. Igeo showed the risks of contamination in a range of unpolluted (Cr, Ni) to strongly polluted (Hg and Cd) categories. RI came up with the contamination ranges from low (Cr, Ni, Cu, Zn, As, and Pb) to extreme (Cd and Hg) risk of contamination. The risk of contamination based on PIN was from safe (Cu, As, and Pb) to seriously high (Cd and Hg). The results yielded by PIN indicated the extreme risk of Cd and Hg in the city. Positive Matrix Factorization was used to identify the sources of contamination. Factor 1 (vehicular exhaust), Factor 2 (coal combustion), Factor 3 (metal industry), and Factor 4 (anthropogenic activities), respectively, contributed 14.63%, 35.34%, 36.14%, and 13.87% of total heavy metal pollution. Metal’s presence in the dust is a direct health risk for humans and warrants immediate and effective pollution control and prevention measures in the city.


2021 ◽  
Vol 13 (2) ◽  
pp. 804
Author(s):  
Jean Dubé ◽  
Maha AbdelHalim ◽  
Nicolas Devaux

Many applications have relied on the hedonic pricing model (HPM) to measure the willingness-to-pay (WTP) for urban externalities and natural disasters. The classic HPM regresses housing price on a complete list of attributes/characteristics that include spatial or environmental amenities (or disamenities), such as floods, to retrieve the gradients of the market (marginal) WTP for such externalities. The aim of this paper is to propose an innovative methodological framework that extends the causal relations based on a spatial matching difference-in-differences (SM-DID) estimator, and which attempts to calculate the difference between sale price for similar goods within “treated” and “control” groups. To demonstrate the potential of the proposed spatial matching method, the researchers present an empirical investigation based on the case of a flood event recorded in the city of Laval (Québec, Canada) in 1998, using information on transactions occurring between 1995 and 2001. The research results show that the impact of flooding brings a negative premium on the housing price of about 20,000$ Canadian (CAN).


2020 ◽  
Vol 13 (1) ◽  
pp. 261
Author(s):  
Christos Petsas ◽  
Marinos Stylianou ◽  
Antonis Zorpas ◽  
Agapios Agapiou

The air quality of modern cities is considered an important factor for the quality of life of humans and therefore is being safeguarded by various international organizations, concentrating on the mass concentration of particulate matter (PM) with an aerodynamic diameter less than 10, 2.5 and 1 μm. However, the different physical and anthropogenic processes and activities within the city contribute to the rise of fine (<1 μm) and coarse (>1 μm) particles, directly impacting human health and the environment. In order to monitor certain natural and anthropogenic events, suspecting their significant contribution to PM concentrations, seven different events taking place on the coastal front of the city of Limassol (Cyprus) were on-site monitored using a portable PM instrument; these included both natural (e.g., dust event) and anthropogenic (e.g., cement factory, meat festival, tall building construction, tire factory, traffic jam, dust road) emissions taking place in spring and summer periods. The violations of the limits that were noticed were attributed mainly to the various anthropogenic activities taking place on-site, revealing once more the need for further research and continuous monitoring of air quality.


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Richard Jumeau ◽  
Patrice Bourson ◽  
Michel Ferriol ◽  
François Lahure ◽  
Marc Ponçot ◽  
...  

The possibilities of applications of vibrational spectroscopy techniques (Raman spectroscopy) in the analysis and characterization of polymers are more and more used and accurate. In this paper, our purpose is to characterize Low Density Poly(Ethylene) (LDPE) grades by Raman spectroscopy and in particular with CH2 Raman vibration modes. With temperature measurements, we determine different amorphous and crystalline Raman assignments. From these results and on the basis of the evolution of CH2 bending Raman vibration modes, we develop a phenomenological model in correlation with Differential Scanning Calorimetry and in particular with crystalline lamella thickness determination.


Author(s):  
Nguyen Hong Nam ◽  
Le Gia Thanh Truc ◽  
Khuong Duy Anh ◽  
Laurent Van De Steene

Agricultural and forest residues are potential sources of renewable energy in various countries. However, the difference in characteristics of biomass resources presents challenges for energy conversion processes which often require feedstocks that are physically and chemically consistent. This study presented a complete and comprehensive database of characteristics of a wide range of agricultural and forest residues. Moisture, bulk density, calorific value, proximate and elemental compositions, as well as cellulose, hemicellulose, and lignin compositions of a wide range of biomass residues were analyzed. The major impacts of the variability in biomass compositions to biochemical and thermochemical processes were also discussed.


Author(s):  
Constantin Bulimaga ◽  
◽  
Anastasia Portarescu ◽  

Anthropogenic activities cause damage to the natural ecosystems in the city in various ways, which contributes to the reduction of biodiversity. Considering that biodiversity is becoming more vulnerable to the impact action triggered by urban activities is necessary to monitor it in order to take urgent measures to protect and preserve it. The plant biodiversity study methodology includes methods that help determine phytocenosis parameters and assess biomass in order to estimate the productive potential of phytocenosis. Carrying out the research according to the proposed methodology will make it possible to assess the anthropogenic impact on the terrestrial and riparian vegetation.


MRS Advances ◽  
2017 ◽  
Vol 2 (49) ◽  
pp. 2689-2694
Author(s):  
Karla A. Gaspar-Ovalle ◽  
Juan V. Cauich-Rodriguez ◽  
Armando Encinas

ABSTRACTNanofibrous mats of poly ε-caprolactone (PCL) were fabricated by electrospinning. The nanofiber structures were investigated and characterized by scanning electron microscope, differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, static water-contact-angle analysis and mechanical properties. The results showed that the nanofibrous PCL is an ideal biopolymer for cell adhesion, owing to its biocompatibility, biodegradability, structural stability and mechanical properties. Differential scanning calorimetry results showed that the fibrous structure of PCL does not alter its crystallinity. Studies of the mechanical properties, wettability and degradability showed that the structure of the electrospun PCL improved the tensile modulus, tensile strength, wettability and biodegradability of the nanotemplates. To evaluate the nanofibrous structure of PCL on cell adhesion, osteoblasts cells were seeded on these templates. The results showed that both adhesion and proliferation of the cells is viable on these electrospun PCL membranes. Thus electrospinning is a relatively inexpensive and scalable manufacturing technique for submicron to nanometer diameter fibers, which can be of interest in the commodity industry.


Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3293 ◽  
Author(s):  
C. Broadhurst ◽  
Walter Schmidt ◽  
Jianwei Qin ◽  
Kuanglin Chao ◽  
Moon Kim

Background: Gradient temperature Raman spectroscopy (GTRS) applies the continuous temperature gradients utilized in differential scanning calorimetry (DSC) to Raman spectroscopy, providing a new means for rapid high throughput material identification and quality control. Methods: Using 20 Mb three-dimensional data arrays with 0.2 °C increments and first/second derivatives allows complete assignment of solid, liquid and transition state vibrational modes. The entire set or any subset of the any of the contour plots, first derivatives or second derivatives can be utilized to create a graphical standard to quickly authenticate a given source. In addition, a temperature range can be specified that maximizes information content. Results: We compared GTRS and DSC data for five commercial fish oils that are excellent sources of docosahexaenoic acid (DHA; 22:6n-3) and eicosapentaenoic acid (EPA; 20:5n-3). Each product has a unique, distinctive response to the thermal gradient, which graphically and spectroscopically differentiates them. We also present detailed Raman data and full vibrational mode assignments for EPA and DHA. Conclusion: Complex lipids with a variety of fatty acids and isomers have three dimensional structures based mainly on how structurally similar sites pack. Any localized non-uniformity in packing results in discrete “fingerprint” molecular sites due to increased elasticity and decreased torsion.


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