Degradation of
            Rhodococcus erythropolis
            SY095 modified with functional magnetic Fe
            3
            O
            4
            nanoparticles

Alkali-surfactant-polymer flooding technology is widely employed to extract crude oil to enhance its production. The bacterial strain Rhodococcus erythropolis SY095 has shown high degradation activity of alkane of crude oil. In the past, many treatment strategies have been implemented to reduce oil concentration in wastewater. Previous studies mainly focused on the extracellular products of Erythrococcus rather than its degradation properties. In the current study, we designed an immobilization method to modify the surface of R. erythropolis SY095 with functional Fe 3 O 4 nanoparticles (NPs) for biodegradation of crude oil and separation of the immobilized bacteria after degradation. We characterize the synthesized NPs through various methods, including scanning electron microscope energy-dispersive spectrometer, Fourier transform infrared spectroscopy, X-ray diffraction (XRD) and a vibrating sample magnetometer. We found that the size of the synthesized NPs was approximately 100 nm. Our results showed that R. erythropolis SY095 was successfully coated with functional magnetic NPs (MNPs) that could be easily separated from the solution via the application of an external magnetic field. The coated cells had a high tolerance for heavy metals. Our findings demonstrated that the immobilization of MNPs to bacterial surfaces is a promising approach for the degradation of crude oil.

Download Full-text

Feldspar-banana peel composite adsorbent for efficient crude oil removal from solution

Applied Water Science ◽

10.1007/s13201-020-01335-8 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Folasegun A. Dawodu ◽

Chika J. Abonyi ◽

Kovo G. Akpomie

Keyword(s):

Crude Oil ◽

Oil Spill ◽

Sem Analysis ◽

Banana Peel ◽

X Ray Diffraction ◽

Hydrophilic Nature ◽

Oil Concentration ◽

Pseudo Second Order ◽

Xrd Techniques ◽

Kinetics Of

AbstractThe problem of oil spill pollution associated with the transport of crude oil and its products across the globe is of serious concern. The sorption technique has proved to be promising for oil spill treatment but is limited by the hydrophilic nature of most natural organic sorbents. The combo of natural organic and inorganic sorbents have been found to enhance the hydrophobicity for oil sorption. Therefore this study was aimed at the preparation of a novel feldspar-banana peel biochar composite (FBPC) with enhanced hydrophobicity for the sorption of crude oil. The prepared sorbent was characterised by the scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques, while the crude oil was characterised using standard methods. Batch sorption was used to determine the effect of contact time (30–150 min), temperature (25–100 °C), pH (2.0–10.0), oil concentration (4.0–12.0 g/L) and sorbent dosage (0.1–0.5 g) on sorption. SEM analysis of FBPC revealed a porous structure, while XRD confirmed the crystalline phases of feldspar. The crude oil samples had pH (6.40–6.60), density (0.960 0 0.962 g/cm3), kinematic viscosity (24.0–27.6 cSt) and API gravity (24.25–24.51°). The Langmuir model with R2 > 0.7781 presented the best fit than the Temkin and Freundlich model in the isotherm analysis, while the pseudo-second-order model with R2 > 0.9711 was applicable in the kinetics of sorption. The thermodynamic analysis revealed a decrease in randomness at the crude oil-FBPC interface. The prepared FBPC was found to be an efficient inorganic–organic composite sorbent with enhanced hydrophobicity for the sorption of crude oil.

Download Full-text

Pitting Corrosion and Microstructure of J55 Carbon Steel Exposed to CO2/Crude Oil/Brine Solution under 2–15 MPa at 30–80 °C

Materials ◽

10.3390/ma11122374 ◽

2018 ◽

Vol 11 (12) ◽

pp. 2374 ◽

Cited By ~ 1

Author(s):

Haitao Bai ◽

Yongqing Wang ◽

Yun Ma ◽

Peng Ren ◽

Ningsheng Zhang

Keyword(s):

Carbon Steel ◽

Crude Oil ◽

Energy Dispersive Spectrometer ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Corrosion Properties ◽

Brine Solution ◽

Maximum Value ◽

Production Wells ◽

Well Depth

This study aimed to evaluate the corrosion properties of J55 carbon steel immersed in CO2/crude oil/brine mixtures present in the wellbores of CO2-flooded production wells. The main corroded position of wellbore was determined and wellbore corrosion law was provided. Corrosion tests were performed in 30% crude oil/brine solution under the simulated temperature (30–80 °C) and pressure (2–15 MPa) conditions of different well depths (0–1500 m). The corrosion behavior of J55 carbon steel was evaluated through weight-loss measurements and surface analytical techniques, including scanning electron microscopy, energy dispersive spectrometer, X-ray diffraction analysis, and optical digital microscopy. Corrosion rate initially increased and then decreased with increasing well depth, which reached the maximum value of 1050 m. At this well depth, pressure and temperature reached 11 MPa and 65 °C, respectively. Under these conditions, FeCO3 and CaCO3 localized on sample surfaces. Microscopy was performed to investigate corrosion depth distribution on the surfaces of the samples.

Download Full-text

Biodegradation of crude oil by immobilized Exiguobacterium sp. AO-11 and shelf life evaluation

Scientific Reports ◽

10.1038/s41598-021-92122-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Chatsuda Sakdapetsiri ◽

Nitchakarn Kaokhum ◽

Onruthai Pinyakong

Keyword(s):

Crude Oil ◽

Shelf Life ◽

Immobilized Cells ◽

Oil Removal ◽

Oil Dispersant ◽

Rate Of Reaction ◽

Oil Concentration ◽

Degradation Activity ◽

The Relationship ◽

Kinetics Of

AbstractExiguobacterium sp. AO-11 was immobilized on bio-cord at 109 CFU g−1 carrier for the removal of crude oil from marine environments. To prepare a ready-to-use bioremediation product, the shelf life of the immobilized cells was calculated. Approximately 90% of 0.25% (v/v) crude oil removal was achieved within 9 days when the starved state of immobilized cells was used. The oil removal activity of the immobilized cells was maintained in the presence of oil dispersant (89%) and at pH values of 7–9. Meanwhile, pH, oil concentration and salinity affected the oil removal efficacy. The immobilized cells could be reused for at least 5 cycles. The Arrhenius equation describing the relationship between the rate of reaction and temperature was validated as a useful model of the kinetics of retention of activity by an immobilized biocatalyst. It was estimated that the immobilized cells could be stored in a non-vacuum bag containing phosphate buffer (pH 7.0) at 30 °C for 39 days to retain the cells at 107 CFU g−1 carrier and more than 50% degradation activity. These results indicated the potential of using bio-cord-immobilized crude oil-degrading Exiguobacterium sp. AO-11 as a bioremediation product in a marine environment.

Download Full-text

Hexagonal WO3·0.33H2O Hierarchical Microstructure with Efficient Photocatalytic Degradation Activity

Catalysts ◽

10.3390/catal11040496 ◽

2021 ◽

Vol 11 (4) ◽

pp. 496

Author(s):

Wei Li ◽

Tingting Wang ◽

Dongdong Huang ◽

Chan Zheng ◽

Yuekun Lai ◽

...

Keyword(s):

Photocatalytic Degradation ◽

Field Emission ◽

Tungsten Trioxide ◽

Orthorhombic Phase ◽

X Ray Diffraction ◽

Hierarchical Microstructure ◽

Energy Devices ◽

Bet Specific Surface Area ◽

Degradation Activity ◽

Degradation Properties

Structural design and morphological control of semiconductors is considered to be one of the most effective ways to improve their photocatalytic degradation properties. In the present work, a hexagonal WO3·0.33H2O hierarchical microstructure (HWHMS) composed of nanorods was successfully prepared by the hydrothermal method. The morphology of the HWHMS was confirmed by field-emission scanning electron microscopy, and X-ray diffraction, Raman spectroscopy, and thermogravimetric analysis demonstrated that the synthesized product was orthorhombic WO3·0.33H2O. Owing to the unique hierarchical microstructure, the HWHMS showed larger Brunauer–Emmett–Teller (BET) surface and narrower bandgap (1.53 eV) than the isolated WO3·0.33H2O nanorods. Furthermore, the HWHMS showed enhanced photocatalytic activity for degradation of methylene blue under visible-light irradiation compared with the isolated nanorods, which can be ascribed to the narrower bandgap, larger BET specific surface area, and orthorhombic phase structure of the HWHMS. This work provides a potential protocol for construction of tungsten trioxide counterparts and materials similar to tungsten trioxide for application in gas sensors, photocatalysts, electrochromic devices, field-emission devices, and solar-energy devices.

Download Full-text

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

Download Full-text

RNA polymerase: Preparation and structural analysis of helical polymers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010011091x ◽

1984 ◽

Vol 42 ◽

pp. 152-153

Author(s):

E. Loren Buhle ◽

Pamela Rew ◽

Ueli Aebi

Keyword(s):

Structural Analysis ◽

Rna Polymerase ◽

Molecular Level ◽

X Ray Diffraction ◽

Helical Polymers ◽

X Ray ◽

E Coli ◽

The Past ◽

Ordered Arrays ◽

Low Ionic Strength

While DNA-dependent RNA polymerase represents one of the key enzymes involved in transcription and ultimately in gene expression in procaryotic and eucaryotic cells, little progress has been made towards elucidation of its 3-D structure at the molecular level over the past few years. This is mainly because to date no 3-D crystals suitable for X-ray diffraction analysis have been obtained with this rather large (MW ~500 kd) multi-subunit (α2ββ'ζ). As an alternative, we have been trying to form ordered arrays of RNA polymerase from E. coli suitable for structural analysis in the electron microscope combined with image processing. Here we report about helical polymers induced from holoenzyme (α2ββ'ζ) at low ionic strength with 5-7 mM MnCl2 (see Fig. 1a). The presence of the ζ-subunit (MW 86 kd) is required to form these polymers, since the core enzyme (α2ββ') does fail to assemble into such structures under these conditions.

Download Full-text

Recent Nanocarrier Approaches for Targeted Drug Delivery in Cancer Therapy

Current Molecular Pharmacology ◽

10.2174/1874467213666200730114943 ◽

2020 ◽

Vol 13 ◽

Author(s):

Rohit Bhatia ◽

Amit Sharma ◽

Raj Kumar Narang ◽

Ravindra K. Rawal

Keyword(s):

Drug Delivery ◽

Polymeric Micelles ◽

Mesoporous Silica Nanoparticles ◽

Treatment Strategies ◽

Human Beings ◽

The Past ◽

Organ Systems ◽

Metal Organic ◽

Continuous Progress ◽

Chemotherapeutic Treatment

: Cancer is one of the most serious health concerns in 21st century whose prevalence is beyond boundaries and can affect any organ of human beings. The conventional chemotherapeutic treatment strategies lack specificity to tumours and are associated with toxic effects on immune system and other organ systems. In the past decades, there has been a continuous progress in the development of smart nanocarrier systems for target specific delivery of drugs against variety of tumours including intracellular gene-specific targeting. These nanocarriers are able to recognize the tumour cells and deliver the therapeutic agent in fixed proportions causing no or very less harm to healthy cells. Nanosystems have modified physicochemical properties, improved bioavailability and long retention in blood which enhances their potency. A huge number of nanocarrier based formulations have been developed and are in clinical trials. Nanocarrier systems include polymeric micelles, liposomes, dendrimers, carbon nanotubes, gold nanoparticles, etc. Recent advancements in nanocarrier systems include mesoporous silica nanoparticles (MSNs), metal organic frame works and quantum dots. In the present review, various nanocarrier based drug delivery systems along with their applications in the management of cancer have been described with special emphasis on MSNs.

Download Full-text

Clinician-Reported Patient Awareness of Symptoms and Severity of Tardive Dyskinesia in Patients Prescribed VMAT2 Inhibitors

CNS Spectrums ◽

10.1017/s1092852920002400 ◽

2021 ◽

Vol 26 (2) ◽

pp. 151-151

Author(s):

Jonathan M. Meyer ◽

Ericha Franey ◽

Leslie Lundt ◽

Betsy Benning ◽

Edward Goldberg ◽

...

Keyword(s):

Tardive Dyskinesia ◽

Symptom Severity ◽

Primary Care Physicians ◽

Additional Data ◽

Treatment Strategies ◽

Vesicular Monoamine Transporter ◽

Patient Awareness ◽

Patient Demographics ◽

The Past ◽

Body Regions

AbstractObjectiveVesicular monoamine transporter 2 (VMAT2) inhibitors including valbenazine are first-line therapies for tardive dyskinesia (TD), a persistent movement disorder associated with antipsychotic exposure. This real-world study was performed to assess the association between patient awareness of TD symptoms and clinician-assessed symptom severity.MethodsClinicians who treated antipsychotic-induced TD with a VMAT2 inhibitor within the past 24 months were asked to extract demographic/clinical data from patients charts and complete a survey for additional data, including patient awareness of TD (yes/no) and TD symptom severity (mild/moderate/severe).ResultsData for 601 patients were provided by 163 clinicians (113 psychiatrists; 46 neurologists; 4 primary care physicians). Patient demographics: 50% male; mean age 50.6 years; 55% schizophrenia/schizoaffective disorder; 29% bipolar disorder; 16% other psychiatric diagnoses. Positive relationships were seen between patient awareness and clinician-assessed symptom severity. Awareness was highest in patients with severe symptoms in specific body regions: face (88% vs 78%/69% [awareness by severe vs moderate/mild symptoms]); jaw (90% vs 80%/67%); wrists (90% vs 69%/63%). In other regions, awareness was similar in patients with severe or moderate symptoms: lips (85%/86% vs 68% [severe/moderate vs mild]); tongue (81%/80% vs 73%); neck (80%/78% vs 68%); arms (67%/66% vs 62%); knees (67%/67% vs 53%).ConclusionsIn patients prescribed a VMAT2 inhibitor for TD, patient awareness was generally higher in those determined to have moderate-to-severe symptom severity as assessed by the clinician. More research is needed to understand how awareness and severity contribute to TD burden, and whether different treatment strategies are needed based on these factors.FundingNeurocrine Biosciences, Inc.

Download Full-text

Experimental and Physico-Chemical Comparison of ZnO Nanoparticles’ Activity for Photocatalytic Applications in Wastewater Treatment

Catalysts ◽

10.3390/catal11060678 ◽

2021 ◽

Vol 11 (6) ◽

pp. 678

Author(s):

Stefano Alberti ◽

Irene Basciu ◽

Marco Vocciante ◽

Maurizio Ferretti

Keyword(s):

Wastewater Treatment ◽

Zno Nanoparticles ◽

Energy Dispersive Spectrometer ◽

Chemical Properties ◽

X Ray Diffraction ◽

Commercial Sample ◽

Synthetic Process ◽

Physico Chemical ◽

Photocatalytic Applications ◽

Reflectance Measurements

In this contribution, the photoactivity upon activation by simulated sunlight of zinc oxide (ZnO) obtained from two different synthetic pathways (Acetate and Nitrate) is investigated for water purification. Different reagents and processes were exploited to obtain ZnO nanoparticles. Products have been characterized by means of X-Ray Diffraction, Scanning Electron Microscopy along with Energy Dispersive Spectrometer, Dynamic Light Scattering, and Diffuse Reflectance Measurements, to highlight the different outcomes ascribable to each synthesis. A comparison of characteristics and performances was also carried out with respect to commercial ZnO. Nanoparticles of this semiconductor can be obtained as aggregates with different degrees of purity, porosity, and shape, and their physical-chemical properties have been addressed to the specific use in wastewater treatment, testing their effectiveness on the photocatalytic degradation of methylene blue (MB) as a model pollutant. Excluding the commercial sample, experimental results evidenced a better photocatalytic behavior for the ZnO Nitrate sample annealed at 500 °C, which was found to be pure and stable in water, suggesting that ZnO could be effectively exploited as a heterogeneous photocatalyst for the degradation of emerging pollutants in water, provided that thermal treatment is included in the synthetic process.

Download Full-text