scholarly journals In Situ Bioremediation

2017 ◽  
Author(s):  
Martin Romantschuk ◽  
Riikka Mäkelä ◽  
Vuokko Malk ◽  
Harri Talvenmäki ◽  
Aki Sinkkonen ◽  
...  
Keyword(s):  
Organic Contaminants ◽  
Oil Spills ◽  
Field Tests ◽  
Treatment Method ◽  
Laboratory Modeling ◽  
Contaminant Degradation ◽  
Treatment Measures ◽  
New Research ◽  
Physical And Chemical

For more than 20 years we have tested various approaches for enhancement of bioremediation of sites polluted by organic contaminants. Through collaboration with contractors and site owners, more than 10 actual sites presenting typical problems have been targets for testing and optimization, first by laboratory modeling, and then by applying  lab experiences in application scale. Samples from the sites were used in controlled laboratory conditions to build micro- and mesocosm- setups in which biological, physical, and chemical treatments were tested and combined, with the main goal of achieving optimal biostimulation and contaminant degradation. As soon as lab results were available, these were utilized for in situ field purposes. Lab and field tests were run in parallel, so that each new challenge in the field treatment generated modifications in the laboratory testing, and each new full scale treatment method was preceded by laboratory modeling. Successful bioremediation was achieved in most of the target cases. Lab testing also created the knowledge when not to use bioremediation, and this can be regarded as one of the utilities of our results. Fresh oil spills resulting from accidents is a new research topic. While old contaminated sites often can rely on an adapted indigenous microbial community, new spill sites may be less responsive to mere biostimulation, and therefore more active treatment measures may be required. The results from this oil spill simulation performed at a lysimeter field are currently being gathered.

scholarly journals What Was Released? Assessing the Physical Properties and Chemical Composition of Petroleum and Products of Burned Oil

Oceanography ◽  
2021 ◽  
Vol 34 (1) ◽  
pp. 44-57
Author(s):  
Jürgen Rullkötter ◽  
John Farrington
Keyword(s):  
Oil Spills ◽  
Complex Mixture ◽  
Chemical Properties ◽  
Analytical Techniques ◽  
Ion Cyclotron Resonance ◽  
Model Calculations ◽  
Research Questions ◽  
Physical And Chemical ◽  
And Chemical Properties

The severity of oil spills depends on the quantity of material released and its physical and chemical properties. The total amount of petroleum spilled during the Deepwater Horizon incident and the relative fractions of the chemical compound classes of the Macondo oil were obtained by measurements, observations, and model calculations, with a significant amount of uncertainty. Because petroleum is an extremely complex mixture of many thousands or more of gaseous, liquid, and solid constituents, full elucidation of their compositions at the molecular level is impossible with presently available analytical techniques. This paper reviews published work on widely used analytical techniques and points out that scientists’ varying approaches to research questions and preferences for methods of analysis constitute a source of uncertainty. In addition, the focus is on two technical advancements developed over the last two decades, namely two-dimensional gas chromatography and Fourier transform ion cyclotron resonance mass spectrometry. Both were particularly valuable in the analysis of the spilled Macondo oil and its weathering products. Among the different processes of alteration of the original oil, only in situ oil burning is dealt with in this paper. This review reveals the paucity of data on this mitigation process and shows the need for more systematic coordination of methods in burned oil research studies.

scholarly journals Microbubbles as Proxies for Oil Spill Delineation in Field Tests

2021 ◽  
Vol 9 (2) ◽  
pp. 126
Author(s):  
Yaomei Wang ◽  
Worakanok Thanyamanta ◽  
Craig Bulger ◽  
Neil Bose ◽  
Jimin Hwang
Keyword(s):  
Residence Time ◽  
Field Experiments ◽  
Oil Spills ◽  
Autonomous Underwater Vehicles ◽  
Field Tests ◽  
Field Trials ◽  
Bubble Plumes ◽  
Acoustic Methods ◽  
Long Endurance

To overcome the environmental impacts of releasing oil into the ocean for testing acoustic methods in field experiments using autonomous underwater vehicles (AUVs), environmentally friendly gas bubble plumes with low rise velocities are proposed in this research to be used as proxies for oil. An experiment was conducted to test the performance of a centrifugal-type microbubble generator in generating microbubble plumes and their practicability to be used in field experiments. Sizes of bubbles were measured with a Laser In-Situ Scattering and Transmissometry sensor. Residence time of bubble plumes was estimated by using a Ping360 sonar. Results from the experiment showed that a larger number of small bubbles were found in deeper water as larger bubbles rose quickly to the surface without staying in the water column. The residence time of the generated bubble plumes at the depth of 0.5 m was estimated to be over 5 min. The microbubble generator is planned to be applied in future field experiments, as it is effective in producing relatively long-endurance plumes that can be used as potential proxies for oil plumes in field trials of AUVs for delineating oil spills.

scholarly journals Comparison of Hydrocarbon-Degrading Consortia from Surface and Deep Waters of the Eastern Mediterranean Sea: Characterization and Degradation Potential

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2246
Author(s):  
Georgia Charalampous ◽  
Efsevia Fragkou ◽  
Konstantinos A. Kormas ◽  
Alexandre B. De Menezes ◽  
Paraskevi N. Polymenakou ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Oil Spills ◽  
Eastern Mediterranean ◽  
Sole Source ◽  
Eastern Mediterranean Sea ◽  
Deep Waters ◽  
Degradation Rates ◽  
Polycyclic Aromatic ◽  
Set Up

The diversity and degradation capacity of hydrocarbon-degrading consortia from surface and deep waters of the Eastern Mediterranean Sea were studied in time-series experiments. Microcosms were set up in ONR7a medium at in situ temperatures of 25 °C and 14 °C for the Surface and Deep consortia, respectively, and crude oil as the sole source of carbon. The Deep consortium was additionally investigated at 25 °C to allow the direct comparison of the degradation rates to the Surface consortium. In total, ~50% of the alkanes and ~15% of the polycyclic aromatic hydrocarbons were degraded in all treatments by Day 24. Approximately ~95% of the total biodegradation by the Deep consortium took place within 6 days regardless of temperature, whereas comparable levels of degradation were reached on Day 12 by the Surface consortium. Both consortia were dominated by well-known hydrocarbon-degrading taxa. Temperature played a significant role in shaping the Deep consortia communities with Pseudomonas and Pseudoalteromonas dominating at 25 °C and Alcanivorax at 14 °C. Overall, the Deep consortium showed a higher efficiency for hydrocarbon degradation within the first week following contamination, which is critical in the case of oil spills, and thus merits further investigation for its exploitation in bioremediation technologies tailored to the Eastern Mediterranean Sea.

scholarly journals The Selection of Treatment Modality for Breast Ductal Carcinoma In Situ: Experience From a Single Institution

2021 ◽  
Vol 28 ◽  
pp. 107327482199742
Author(s):  
Kai-yun You ◽  
Zhuo-fei Bi ◽  
Yu-jia Ma ◽  
Yong-lin Mao ◽  
Wei-liang Zou ◽  
...  
Keyword(s):  
Local Recurrence ◽  
Ductal Carcinoma In Situ ◽  
Adjuvant Radiotherapy ◽  
Carcinoma In Situ ◽  
Ductal Carcinoma ◽  
Multivariable Analysis ◽  
Tumor Grade ◽  
Treatment Method ◽  
Free Survival

Purpose: Although breast conservation surgery(BCS) followed by adjuvant radiotherapy is now the mainstream treatment method for breast ductal carcinoma in situ(DCIS), mastectomy is still performed in some patients who refuse to undergo radiation. However, the most effective treatment method for these patients is still unknown. In the current study, we aimed to compare the survival rates between mastectomy and BCS plus adjuvant radiotherapy in patients with DCIS. Materials and Methods: We performed a retrospective study of 333 patients with DCIS from May 2004 to December 2016. There were 209 patents who were treated with BCS and adjuvant radiotherapy, while the remaining of 124 patients underwent mastectomy. The disease-free survival (DFS) and local recurrence-free survival(LRFS) rates were compared between the 2 treatment groups. Cox proportional hazards regression was performed to explore factors associated with DFS and LRFS. Results: The 10-year local recurrence(LR) rates in the mastectomy and BCS plus adjuvant radiotherapy groups were 2.6% and 7.5%, respectively. There was no difference in the LR rate between the 2 groups. Furthermore the DFS rate was also similar between the mastectomy and BCS plus adjuvant radiotherapy groups. Based on the multivariable analysis, age and tumor grade were significantly correlated with the LRFS and DFS rates. In the subgroup analysis based on the factors of age and tumor grade, patients with a tumor grade of III who underwent mastectomy had better LRFS and DFS rates compared to those who received BCS plus radiotherapy. Conclusion: In patients with DCIS, the long-term efficacy was similar between mastectomy and BCS followed by adjuvant radiotherapy. However, in the subgroup of patients with grade III tumors, mastectomy seems to offer a better LRFS and DFS than BCS plus radiotherapy.

scholarly journals Enhanced Tensile Strength of Monolithic Epoxy with Highly Dispersed TiO2-Graphene Nanocomposites

2021 ◽  
Vol 5 (7) ◽  
pp. 191
Author(s):  
Yanshuai Wang ◽  
Siyao Guo ◽  
Biqin Dong ◽  
Feng Xing
Keyword(s):  
Tensile Strength ◽  
Epoxy Resin ◽  
Mechanical Performance ◽  
Chemical Properties ◽  
High Mechanical Property ◽  
Graphene Nanocomposites ◽  
Highly Dispersed ◽  
Dispersion State ◽  
Physical And Chemical

The functionalization of graphene has been reported widely, showing special physical and chemical properties. However, due to the lack of surface functional groups, the poor dispersibility of graphene in solvents strongly limits its engineering applications. This paper develops a novel green “in-situ titania intercalation” method to prepare a highly dispersed graphene, which is enabled by the generation of the titania precursor between the layer of graphene at room temperature to yield titania-graphene nanocomposites (TiO2-RGO). The precursor of titania will produce amounts of nano titania between the graphene interlayers, which can effectively resist the interfacial van der Waals force of the interlamination in graphene for improved dispersion state. Such highly dispersed TiO2-RGO nanocomposites were used to modify epoxy resin. Surprisingly, significant enhancement of the mechanical performance of epoxy resin was observed when incorporating the titania-graphene nanocomposites, especially the improvements in tensile strength and elongation at break, with 75.54% and 176.61% increases at optimal usage compared to the pure epoxy, respectively. The approach presented herein is easy and economical for industry production, which can be potentially applied to the research of high mechanical property graphene/epoxy composite system.

scholarly journals Investigation of the Formation Mechanism and Environmental Risk of Tire—Pavement Wearing Waste (TPWW)

2021 ◽  
Vol 13 (15) ◽  
pp. 8172
Author(s):  
Kechen Wang ◽  
Xiangyu Chu ◽  
Jiao Lin ◽  
Qilin Yang ◽  
Zepeng Fan ◽  
...  
Keyword(s):  
Formation Mechanism ◽  
Organic Contaminants ◽  
Asphalt Mixture ◽  
Fine Fraction ◽  
Crumb Rubber ◽  
Environmental Benefit ◽  
The Road ◽  
Open Graded Friction Course ◽  
Volatile Alkanes ◽  
Physical And Chemical

Tire—pavement interaction behaviours result in large amounts of wearing waste matter, which attaches to the surface of the pavement and is directly exposed to the surrounding environment. This kind of matter imposes a great challenge to the environment of the road area. The current study is devoted to carrying out a comprehensive investigation of the formation mechanism of tire—pavement wearing waste (TPWW), as well as the resulting environmental risks. A self-developed piece of accelerated polishing equipment, the Harbin advanced polishing machine (HAPM), was employed to simulate the wearing process between vehicle tires and pavement surfaces, and the TPWW was collected to conduct morphological, physical, and chemical characterisations. The results from this study show that the production rate of TPWW decreases with the increase in polishing duration, and the coarse particles (diameters greater than 0.425 mm) account for most of the TPWW obtained. The fine fraction (diameter smaller than 0.425 mm) of the TPWW comprises variously sized and irregularly shaped rubber particles from the tire, as well as uniformly sized and angular fine aggregates. The environmental analysis results show that volatile alkanes (C9–C16) are the major organic contaminants in TPWW. The Open-Graded Friction Course (OGFC) asphalt mixture containing crumb rubber as a modifier showed the highest risk of heavy metal pollution, and special concern must be given to tire materials for the purpose of improving the environmental conditions of road areas. The use of polyurethane as a binder material in the production of pavement mixtures has an environmental benefit in terms of pollution from both organic contaminants and heavy metals.

The Vyredox and Nitredox Methods of in situ Treatment of Groundwater

1988 ◽  
Vol 20 (3) ◽  
pp. 149-163 ◽  
Author(s):  
Carol Braester ◽  
Rudolf Martinell
Keyword(s):  
Water Treatment ◽  
Surface Water ◽  
Traditional Method ◽  
Treatment Method ◽  
Nitrate Treatment ◽  
The Past ◽  
The World ◽  
Nitrate And Nitrite ◽  
Iron And Manganese

Nearly one fifth of all water used in the world is obtained from groundwater. The protection of water has become a high priority goal. During the last decades pollution of water has become more and more severe. Today groundwater is more and more used in comparison with surface water. Recently we have seen accidents, which can pollute nearly all surface water very quickly. Generally the groundwater is easier to protect, as well as cheaper to purify, and above all it is of better quality than the surface water. During the past two decades, alternatives to the traditional method of treating the water in filters have been developed, that is in situ water treatment i.e. the VYREDOX and NITREDOX methods. The most common problem regarding groundwater is too high content of iron and manganese, which can be reduced with the VYREDOX method. In some areas today there are severe problems with pollution by hydrocarbons and nitrate as well, and with modification of the VYREDOX treatment method it is used for hydrocarbon and nitrate treatment as well. The method to reduce the nitrate and nitrite is known as the NITREDOX method.

scholarly journals Underwater Holographic Sensor for Plankton Studies In Situ Including Accompanying Measurements

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4863
Author(s):  
Victor Dyomin ◽  
Alexandra Davydova ◽  
Igor Polovtsev ◽  
Alexey Olshukov ◽  
Nikolay Kirillov ◽  
...  
Keyword(s):  
World Ocean ◽  
Field Tests ◽  
Field Measurements ◽  
Measuring Systems ◽  
Water Turbidity ◽  
Background Data ◽  
Average Size ◽  
Size Dispersion

The paper presents an underwater holographic sensor to study marine particles—a miniDHC digital holographic camera, which may be used as part of a hydrobiological probe for accompanying (background) measurements. The results of field measurements of plankton are given and interpreted, their verification is performed. Errors of measurements and classification of plankton particles are estimated. MiniDHC allows measurement of the following set of background data, which is confirmed by field tests: plankton concentration, average size and size dispersion of individuals, particle size distribution, including on major taxa, as well as water turbidity and suspension statistics. Version of constructing measuring systems based on modern carriers of operational oceanography for the purpose of ecological diagnostics of the world ocean using autochthonous plankton are discussed. The results of field measurements of plankton using miniDHC as part of a hydrobiological probe are presented and interpreted, and their verification is carried out. The results of comparing the data on the concentration of individual taxa obtained using miniDHC with the data obtained by the traditional method using plankton catching with a net showed a difference of no more than 23%. The article also contains recommendations for expanding the potential of miniDHC, its purpose indicators, and improving metrological characteristics.

scholarly journals Molecular biology approaches in bioadhesion research

2014 ◽  
Vol 5 ◽  
pp. 983-993 ◽  
Author(s):  
Marcelo Rodrigues ◽  
Birgit Lengerer ◽  
Thomas Ostermann ◽  
Peter Ladurner
Keyword(s):  
Molecular Biology ◽  
Biological Function ◽  
Molecular Approach ◽  
Research Groups ◽  
Blast Search ◽  
Search Facility ◽  
New Research ◽  
And Function ◽  
Functional Analyses

The use of molecular biology tools in the field of bioadhesion is still in its infancy. For new research groups who are considering taking a molecular approach, the techniques presented here are essential to unravelling the sequence of a gene, its expression and its biological function. Here we provide an outline for addressing adhesion-related genes in diverse organisms. We show how to gradually narrow down the number of candidate transcripts that are involved in adhesion by (1) generating a transcriptome and a differentially expressed cDNA list enriched for adhesion-related transcripts, (2) setting up a BLAST search facility, (3) perform an in situ hybridization screen, and (4) functional analyses of selected genes by using RNA interference knock-down. Furthermore, latest developments in genome-editing are presented as new tools to study gene function. By using this iterative multi-technologies approach, the identification, isolation, expression and function of adhesion-related genes can be studied in most organisms. These tools will improve our understanding of the diversity of molecules used for adhesion in different organisms and these findings will help to develop innovative bio-inspired adhesives.

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