scholarly journals Methods of Analyzing Microsized Plastics in the Environment

2021 ◽  
Vol 11 (22) ◽  
pp. 10640
Author(s):  
Hyunjeong Woo ◽  
Kangmin Seo ◽  
Yonghyun Choi ◽  
Jiwon Kim ◽  
Masayoshi Tanaka ◽  
...  
Keyword(s):  
Thermal Analyses ◽  
False Negative ◽  
Chemical Properties ◽  
Environmental Matrices ◽  
Negative Results ◽  
False Negative Results ◽  
The Subject ◽  
Organic Particles ◽  
Physical And Chemical ◽  
And Chemical Properties

Microplastics are found in various environments with the increasing use of plastics worldwide. Several methods have been developed for the sampling, extraction, purification, identification, and quantification of microplastics in complex environmental matrices. This study intends to summarize recent research trends on the subject. Large microplastic particles can be sorted manually and identified through chemical analysis; however, sample preparation for small microplastic analysis is usually more difficult. Microplastics are identified by evaluating the physical and chemical properties of plastic particles separated through extraction and washing steps from a mixture of inorganic and organic particles. This identification has a high risk of producing false-positive and false-negative results in the analysis of small microplastics. Currently, a combination of physical (e.g., microscopy), chemical (e.g., spectroscopy), and thermal analyses is widely used. We aim to summarize the best strategies for microplastic analysis by comparing the strengths and limitations of each identification method.

scholarly journals Graphene as signal amplifier for preparation of ultrasensitive electrochemical biosensors

2015 ◽  
Vol 69 (1) ◽  
Author(s):  
Jaroslav Filip ◽  
Peter Kasák ◽  
Jan Tkac
Keyword(s):  
Chemical Properties ◽  
Electrochemical Biosensors ◽  
Diverse Range ◽  
High Expectations ◽  
Operational Characteristics ◽  
Signal Amplifier ◽  
Different Types ◽  
The Subject ◽  
Physical And Chemical ◽  
And Chemical Properties

AbstractEarly diagnosis of diseases with minimal cost and time-consumption has become achievable due to recent advances in the development of biosensors. These devices use biorecognition elements for the selective interaction with an analyte and the signal read-out is obtained via different types of transducers. The operational characteristics of biosensors have been reported as improving substantially when a diverse range of nanomaterials is employed. This review presents the construction of electrochemical biosensors based on graphene, atomically thin 2D carbon crystals, a nanomaterial currently the subject of intensive studies. Here, the most attractive directions for graphene applications in biosensor preparation are discussed, including novel detection and amplification schemes exploiting graphene’s unique electrochemical, physical and chemical properties. There is probably a very bright future for graphene-based biosensors, but much further work is required to fulfill the high expectations.

Mineral Oils as Mosquito Larvicides.

1936 ◽  
Vol 27 (2) ◽  
pp. 289-305 ◽  
Author(s):  
David R. P. Murray
Keyword(s):  
Microscopic Examination ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Suitable Material ◽  
Mineral Oils ◽  
The Subject ◽  
Mosquito Larvicides ◽  
Physical And Chemical ◽  
And Chemical Properties

Oil has been used as a mosquito larvicide for about forty years, since L. O. Howard in 1892 first recommended its use, and a large literature has accumulated on the subject, but the physical and chemical properties which make an oil a suitable material for this work are very imperfectly understood. It is clear that the problem is one that can very favourably be studied in the laboratory, for it requires above all an answer to the question “How do larvae die under oil treatment?” which can only be answered by microscopic examination of the larvae.

III. On a crystalline fatty acid from human urine

1868 ◽  
Vol 16 ◽  
pp. 135-139
Keyword(s):  
Chemical Properties ◽  
Fatty Degeneration ◽  
Physical And Chemical Properties ◽  
Fatty Matter ◽  
True Solution ◽  
Abnormal State ◽  
Recorded Instance ◽  
The Subject ◽  
Physical And Chemical ◽  
And Chemical Properties

The occurrence of fatty matter in urine is a somewhat rare phenomenon, and is generally considered as a symptom of disease, or at least of an abnormal state of the system. In most cases it is found associated with albumen, forming the so-called “chylous urine,” in which the fatty matter is suspended in such extremely minute particles as to give the liquid the appearance of milk. In a few instances it has occurred in the shape of fluid oil-globules floating about in the urine; but it is more frequently found enclosed in cells, which sink and form a deposit at the bottom of the vessel. Fatty matter is a constituent of kiesteine , the pellicle which is sometimes formed on the surface of the urine of pregnant women, ant fat resembling butter was obtained from it by Lehmann, though by some authors the very existence of kiesteine as a peculiai deposit is doubted. Lastly, a few cases are described in which a fat-like substance was passed with the urine in the form of small concretions, which, when fresh, were soft and elastic, but dried into hard, yellow, wax-like masses (Heller's urostealith ). In no recorded instance was the fatty matter contained in the secretion in a state of true solution. The accounts which are given of the physical and chemical properties of the fatty matters of urine are extremely vague, and quite insufficient to enable us to identify them, so that it may be concluded that in most cases the quantity obtained was extremely small. Dr. Beale has, indeed, shown that the fatty matter which accumulates in the epithelial cells, passed with the urine in some cases of fatty degeneration of the kidney, contains cholesterine; and Berzelius and Lehmann state that urine, when distilled with the addition of sulphuric acid, yields butyric acid; but in other respects our ignorance is almost complete. None of the works devoted to the subject of urine contain a hint which would lead one to suppose that fatty matter in any form is a constituent of the ordinary healthy secretion.

scholarly journals АНАЛІЗ ВПЛИВУ ГАЗОКОНДЕНСАТНИХ ЗАБРУДНЕНЬ НА СТАН ҐРУНТІВ ПОЛТАВЩИНИ

2014 ◽  
pp. 204-207
Author(s):  
О. I. Санжаревська
Keyword(s):  
Oil And Gas ◽  
Oil Spills ◽  
Chemical Properties ◽  
Mineral Resources ◽  
Gas Condensate ◽  
Negative Results ◽  
Agricultural Use ◽  
Physical And Chemical ◽  
Properties Of Soil ◽  
And Chemical Properties

У статті досліджено фізико-хімічні показникиґрунту, забрудненого нафтогазоконденсатноюсумішшю різної давності: 6 місяців, 12 місяців, 36місяців та проведено його порівняння з ґрунтом, не-забрудненим нафтопродуктами на прикладі Полтав-ської області. Визначено головні негативні наслідкивпливу газоконденсату на ґрунтові екосистеми йзроблені висновки про придатність ґрунту для сіль-ськогосподарського використання та можливі шляхийого покращання. Практична значимість роботиполягає в розробці концептуальних засад поліпшеннястану ґрунтів Полтавського регіону, зокрема за ра-хунок фітомеліоративних заходів; обґрунтуваннішляхи локалізації газоконденсатних виливів і віднов-лення ґрунтів після газоконденсатних забруднень. Poltava Region is one of the leading oil and gas extraction regions of Ukraine. Almost 40 % of Ukrainian gas and every fifth ton of oil with condensate are extracted from depths of Poltava Region, which have unique fields of fuel and power as well as mineral resources. However, during extraction, transportation and processing of oil and gas condensate, oil spills occur, which is associated with accidents and unauthorized ties-in. The result is polluted soil, ground and surface water. We have identified the major negative results of influence on the soil ecosystem gas condensate. It was experimentally determined that the basic physical and chemical properties of soil contaminated with a mixture of gas condensate and comparison with uncontaminated soil mineral oil in Poltava. Conclusions were made concerning the suitability of the soil for agricultural use and possible ways to improve it. There were appeared some problems that should be solved for improving soil Poltava.

scholarly journals SELECTION OF MINERAL RAW MATERIAL FIELDS FOR GLAUCONITE SORPTION MATERIALS

2021 ◽  
Vol 2021 (1) ◽  
pp. 11-18
Author(s):  
D Xadjibaev ◽  
◽  
F Erkabaev
Keyword(s):  
Industrial Development ◽  
High Performance ◽  
Raw Materials ◽  
Thermal Analyses ◽  
Chemical Properties ◽  
Sorption Process ◽  
Raw Material ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
And Chemical Properties

Natural minerals, such as bentonite, kaolinite, biotite, vermiculite, and glauconite, which have sufficiently high performance properties in the softening of industrial and waste water, softening and cleaning of heavy metals, are promising. To study the physical and chemical properties of glauconites from various deposits of the country, samples of glauconite mineral were brought from the Parkent, Bukhara, and Karakalpak mountain reserves, their physical and chemical properties were studied, compared with each other, and the optimal reserve was selected. The reserves of these deposits are sufficient and have the potential for industrial development. The purpose of this study is to compare samples of natural mineral reserves of glauconite and select the optimal deposit for raw materials. Methodology. Samples of glauconite minerals from the Parkent, Bukhara and Karakalpak mines were taken as the object of the study. Chemical, mineralogical, and thermal analyses were performed on the samples, and the fractional composition was determined. Scientific novelty. The main part of the mineral glauconite (50-55%) in the raw material is found in fractions of 0.08-0.125 mm. The most suitable raw material was the Parkent glauconite deposit, which has a relatively high content of potassium, which tends to exchange with other metals during the sorption process. The received data. Based on the conducted experiments, samples of glauconites from Parkent, Bukhara, and Karakalpak were subjected to chemical and mineralogical analyses. The maximum amount of the mineral glauconite was found in the fractions of the raw material (less than 0.125 mm). The most suitable deposit of raw materials for processing the mineral glauconite was selected and an environmentally friendly adsorbent was obtained.

scholarly journals The Role of Forensic Anthropology in the Medico-Legal Investigation of Remains Recovered at Sea: Analysis of a Case

2021 ◽  
Vol 1 (3) ◽  
pp. 138-147
Author(s):  
Alessia Leggio ◽  
Pietro Tarzia ◽  
Francesco Introna
Keyword(s):  
Soft Tissues ◽  
Chemical Properties ◽  
Skeletal Remains ◽  
Court Case ◽  
Physical And Chemical Properties ◽  
Biological Profile ◽  
The Subject ◽  
Physical And Chemical ◽  
And Chemical Properties

Forensic anthropological investigations often encounter cases that are difficult to interpret, especially when dealing with skeletal remains found in a marine context. Determining the immersion time in the sea of skeletal remains is a challenge for forensic investigations and answering this would solve many cases in the shortest time possible. The physical and chemical properties of bones change during their time in water and these changes cause difficulties and delays in identifying and reconstructing the biological profile of an unknown subject. In this paper, two forensic cases found at sea were analysed, the case of a disarticulated and extensively skeletonised corpse found on the coast of Reggio Calabria (Italy) and the case of an isolated foot, intact of soft tissues, found only 9 km away, on the coast of Vibo Valentia (Italy). The resolution hypothesis of the two cases was based on three search options because the disappearance of three known individuals was being investigated simultaneously. The investigations were conducted through a multidisciplinary work applying different analyses, including anthropometric, radiological, digital and, finally, genetic analyses. The results made it possible to determine the reconstruction of two biological profiles, both of Case A, the skeletal remain, and Case B, the subject to whom the foot belonged. The almost compatible anthropometric results of the two biological profiles, the presence of two very indicative partial tattoos and a genetic correlation led to the solution of a single court case.

Statistical criteria of stellar population types

1966 ◽  
Vol 24 ◽  
pp. 101-110
Author(s):  
W. Iwanowska
Keyword(s):  
Stellar Population ◽  
Chemical Properties ◽  
Spectrophotometric Study ◽  
Physical And Chemical Properties ◽  
Population Type ◽  
The Galaxy ◽  
Distribution Parameters ◽  
Physical And Chemical ◽  
Statistical Criteria ◽  
And Chemical Properties

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

Tailoring microstructures of materials through biomimetics

1993 ◽  
Vol 51 ◽  
pp. 500-501
Author(s):  
Mehmet Sarikaya ◽  
Ilhan A. Aksay
Keyword(s):  
Chemical Properties ◽  
Design And Synthesis ◽  
Structure Sensitive ◽  
Macro Scale ◽  
Methods Of Synthesis ◽  
Successive Level ◽  
Engineering Materials ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
Synthesis Of Materials

Biomimetics involves investigation of structure, function, and methods of synthesis of biological composite materials. The goal is to apply this information to the design and synthesis of materials for engineering applications.Properties of engineering materials are structure sensitive through the whole spectrum of dimensions from nanometer to macro scale. The goal in designing and processing of technological materials, therefore, is to control microstructural evolution at each of these dimensions so as to achieve predictable physical and chemical properties. Control at each successive level of dimension, however, is a major challenge as is the retention of integrity between successive levels. Engineering materials are rarely fabricated to achieve more than a few of the desired properties and the synthesis techniques usually involve high temperature or low pressure conditions that are energy inefficient and environmentally damaging.In contrast to human-made materials, organisms synthesize composites whose intricate structures are more controlled at each scale and hierarchical order.

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