Chain Aliphatic Hydrocarbons Research Articles

Production of low-sulfur fuels from catalytic pyrolysis of waste tires using formulated red mud catalyst

Waste tires (WT) are produced in millions of tons per annum and their safe disposal is always a major environmental challenge because of fire hazards and the increasing cost of landfills. WT has high organic matter content that can be converted into fuels and chemicals if suitable technologies can be developed. Herein we report the in situ catalytic pyrolysis of WT using formulated red mud catalyst to produce low sulfur fuel that can be fractionated or can be used without fractionation. The in situ catalytic pyrolysis was conducted at 450–550 °C using formulated red mud catalyst. The yield of pyrolysis liquids ranged from 35 to 40 wt%. The liquid was very rich in limonene and long chain aliphatic hydrocarbons. The catalyst was effective in removing the sulfur compounds in the oil through reactive adsorption desulfurization mechanism. The sulfur species reacted with hematite, calcite, sodium hydroxide, and zinc oxide to form sulfides and were retained in the catalyst. The minimum sulfur content of the catalytic pyrolysis oil was 0.38 wt%. After catalyst regeneration in air through combustion, the catalyst activity was restored, and the catalyst was reused.

Novel insights into the molecular structure of lignite and its oxidation characteristics: A comprehensive characterization from single molecule of intermediates to complex coal

The structure of lignite is commonly believed to consist of fused aromatic rings (FARs) with 1 and 2 rings and short methylene chains, with few FARs with 3 or more rings and long aliphatic hydrocarbon (LAH) chains. This work presents a controlled stepwise alkali‑oxygen oxidation (AOO) of Xiaolongtan lignite to produce intermediates with characteristic structures. The humic acids and oxidative residues obtained were rich in aromatics and aliphatics, respectively. Based on complementary information of FARs with 3 or more rings and LAHs in the intermediates, a new structural model of lignite (C3661H3435O1036N81S7) from single molecules of intermediates to complex particles has been developed in conjunction with material characterization and computation. There are 43.7% one fused aromatic ring (1FAR), 39.3% 2FAR, 14.7% 3FAR, and 2.4% 4FAR, amount which there 15.9% pyrrole- and 2.4% pyridines- based aromatic rings. The controlled oxidation could prevent the ring-opening reaction of FARs and excessive oxidation of LAHs, thus leading to an in-depth understanding of the AOO process and lignite structure.

New sorbent-based hydrophobic alginic acid derivatives for fat removal in multi-pesticide residues: analysis of a fatty food sample.

Hydrophobic alginic acid derivatives were synthesized with various aliphatic hydrocarbon chains for fat removal in an analysis of multi-pesticide residues in a fatty food sample. First, alginic acid was chemically modified using eco-friendly ultrasound-assisted esterification with different alcohols, namely, hydrophobic alginic acid-methanol (HAA-C1), hydrophobic alginic acid-butanol (HAA-C4), and hydrophobic alginic acid-octadecanol (HAA-C18). The degree of esterification (DE) was determined by titration, and the results ranged from 57.3% to 63.7%. The physicochemical properties of the synthesized hydrophobic alginic acids (HAAs) were studied using FT-IR, XRD, TGA, and FE-SEM. Subsequently, the performance of the HAAs was checked and evaluated for the removal of fat from a fatty food sample by calculating the fat removal percentage and the determination of 214 pesticide residues in the fatty food sample. For the fat removal percentage application, the HAAs were able to efficiently remove between 77% and 83% of the fat; HAA-C18 had the highest percentage. Regarding the pesticide residue application, HAAs were also able to remove the fat content from the fatty food sample without a significant effect on the pesticide substances. The recoveries of the detected pesticide compounds were between 80% and 120% for all HAAs. However, there were various missing pesticide compounds for HAAs. The number of missing pesticide compounds was 19, 6, and 33 for HAA-C1, HAA-C4, and HAA-C18, respectively. HAA-C4 had medium hydrophobicity and it lost fewer pesticides than the other HAAs. This was because the multi-pesticide mixture had various classes of chemical structure; hence, it had different polarity powers. We concluded that HAAs are developable and applicable to be safely used as a green material in diverse fatty food sample analysis applications.

Synthesis, characterization, and anticancer properties of iminopyridine platinum(II) complexes containing long aliphatic chains

A series of iminopyridine ligands were prepared from the condensation reaction of 6-methylpyridine-2-carboxaldehyde and long-chain aliphatic primary amines. Square planar platinum(II) complexes were synthesized from the reaction of [PtCl2(η2-coe)]2 (coe = cis-cyclooctene) with two equivalents of ligand. The synthesis of the platinum compounds appears to go through a five-coordinate trigonal pyramidal species where coe remains coordinated initially but eventually dissociates to afford the four-coordinate complexes. Ligands and platinum complexes were characterized using multi-nuclear NMR and FT-IR spectroscopies as well as an X-ray diffraction study for the platinum complex derived from n-hexylamine. The cytotoxic properties of the platinum complexes against the ovarian cancer cell line SKOV-3 using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric method were examined. Relative cytotoxicities of the platinum complexes follow a trend of greater potency with increasing chain length against the SKOV-3 cell line, with the longest aliphatic hydrocarbon chain (C16) exhibiting anticancer effects comparable to that of cisplatin.

Production of polypropylene-derived novel porous carbon nanosheets through aromatization stabilization toward supercapacitor applications

Polypropylene (PP) is a promising precursor for porous carbon materials. However, the thermal treatment of PP would generate volatile hydrocarbons, which makes it still a trouble to prepare PP-derived porous carbon by a one-step methodology. Herein, PP-derived carbon nanosheets were successfully prepared by an aromatization stabilization strategy. The hydrogen atoms in PP are deprived by chloride in CuCl2, resulting the dehydrogenated PP. The aliphatic hydrocarbon chain from the dehydrogenated PP would aromatize into a laddered structure that could undergo carbonization without complete decomposition. The deposition of gaseous hydrocarbons from PP on CuCl would enable the formation of porous carbon nanosheets. The carbon nanosheets would experience activation through further hydrogen deprivation reaction at temperatures above 500°C. Benefiting from this nanosheet structure's short ion diffusion pathway, PP-derived carbon exhibited excellent rate performance as supercapacitor electrodes.

Computational Prodrug Design Methodology for Liposome Formulability Enhancement of Small-Molecule APIs.

Encapsulation into liposomes is a formulation strategy that can improve efficacy and reduce side effects of active pharmaceutical ingredients (APIs) that exhibit poor biodistribution or pharmacokinetics when administered alone. However, many APIs are unsuitable for liposomal formulations intended for parenteral administration due to their inherent physicochemical properties─lipid bilayer permeability and water-lipid equilibrium partitioning coefficient. Too high permeability results in premature leakage from liposomes, while too low permeability means the API is not able to pass across biological barriers. There are several options for solving this issue: (i) change of the lipid bilayer composition, (ii) addition of a permeability enhancer, or (iii) modification of the chemical structure of the API to design a prodrug. The latter approach was taken in the present work, and the effect of small changes in the molecular structure of the API on its permeation rate across a lipidic bilayer was systematically explored utilizing computer simulations. An in silico methodology for prodrug design based on the COSMOperm approach has been proposed and applied to four APIs (abiraterone, cytarabine, 5-fluorouracil, and paliperidone). It is shown that the addition of aliphatic hydrocarbon chains via ester or amide bonds can render the molecule more lipophilic and increase its permeability by approximately 1 order of magnitude for each 2 carbon atoms added, while the formation of fructose adducts can provide a more hydrophilic character to the molecule and reduce its lipid partitioning. While partitioning was found to depend only on the size and type of the added group, permeability was found to depend also on the added group location. Overall, it has been shown that both permeability and lipid partitioning coefficient can be systematically shifted into the desired liposome formulability window by appropriate group contributions to the parental drug. This can significantly increase the portfolio of APIs for which liposome or lipid nanoparticle formulations become feasible.

Conversion of Marine Plastic Litter into Chemicals and Fuels through Catalytic Pyrolysis Using Commercial and Coal Fly Ash-Synthesized Zeolites

A marine plastic litter (MPL) sample, collected during a beach cleanup campaign, underwent thermal and catalytic pyrolyses to demonstrate that valuable hydrocarbon oil and gas can be produced from heterogeneous plastic waste, partly aged and not mechanically recyclable. A low-cost H-X zeolite lab synthesized from coal fly ash (CFA) was tested and compared with two commercial zeolites (H-USY and H-ZSM-5) commonly used in the industrial cracking field. MPL characterization revealed it is mainly composed of polyethylene and polypropylene (52 and 45 wt %, respectively), and it has ideal physicochemical properties as feed for pyrolysis processes. Thermogravimetric analyses demonstrated that catalysts can reduce the degradation temperature of MPL from 472 to 425 °C and from 450 to 421, 342, and 380 °C for H-ZSM-5, H-X/CFA, and H-USY, respectively. These results were confirmed by thermal and catalytic pyrolyses tests performed in a bench-scale reactor. All the catalytic tests were carried out at 450 °C with a liquid phase contact mode. In particular, H-X/CFA, avoiding tar and wax formation, produced up to 87 wt % of light oil with a high content of short chain aliphatic hydrocarbons, obtaining results very similar to those gained with the expensive commercial H-USY. For all the catalytic pyrolysis tests, the produced gases proved to be more than sufficient to sustain the process heat requirement.

Examination of the Structure and Definition of the Mechanism of Formation of Products by Pyrolysis of Tarim Crude Oil

Pyrolysis of crude oil is an important way to generate natural gas. However, the current analysis of pyrolysis gas carbon isotopes and the study of gas generation dynamics are not unified, and the genesis and accumulation of gas reservoirs are needed to conduct in-depth discussions. Therefore, Tarim crude oil samples in China were selected to perform thermal simulation experiments using an autoclave. The pyrolysis hydrocarbon production yield, carbon isotope characteristics and gas-generation process of crude oil samples in Tarim Basin were studied by GC-MS, FT-IR and carbon isotope analysis, respectively. The compositions of the Tarim Oilfield were determined, including the 83.69% content of hydrocarbons, the 14.08% content of aromatic compounds, and lower than 3% content of heteroatom compounds. The non-monotonic linear relationship of C2-5 isotopes may be due to the complexity of crude oil, and the formation of gaseous hydrocarbons can be divided into three stages. The results showed that the δ13C distribution range of C2-5 hydrocarbons was −40.5% to −10.5%, and the δ13C distribution of methane was −53.3% to −27.4%. The lowest δ13C value for methane occurs at 350 °C, and the corresponding carbon isotope value is −53.3%. When the pyrolysis temperature range is 250–300 °C, crude oil undergoes volatilization and preliminary pyrolysis, and the C4-5 output exceeds 95%. When the temperature rises to 300–500 °C, the aliphatic hydrocarbon chain in crude oil begins to crack, the side and branch chains of aromatic and heteroatomic compounds are broken, and C4-5 begins to crack to form C1-3. Finally, the temperature rises to 500–600 °C, and C3-5 begins to deeply crack into C1-2, and eventually all is converted to methane.

Insight into influence of process parameters on co-pyrolysis interaction between Yulin coal and waste tire via rapid infrared heating

Co-pyrolysis of coal and waste tire is an important route to realize their clean and efficient utilization. To study the interaction during co-pyrolysis, the rapid infrared-heated fixed-bed reactor was adapted to explore the effects of heating rate, pyrolysis temperature and mixing ratio on the products distribution, tar quality and compositions during the co-pyrolysis of Yulin coal (YL) and waste tire (WT), and the interaction mechanism was also explored. The results show that heating rate, mixing ratio and pyrolysis temperature exerted the synergistic effect during co-pyrolysis. High heating rate was beneficial to the interaction of coal and waste tire, and the maximum positive synergistic effect of tar production was obtained at the heating rate of 10 °C/s. The content of light tar (boiling point < 360 °C) in co-pyrolysis tar increased gradually with amount of WT added in blends. When the mixing ratio of YL/WT was 1:1, the most remarkable difference between the experimental and calculated contents of light tar in tar suggested obvious positive synergy among the blended samples. In addition, gas production was remarkably suppressed during co-pyrolysis. It is analyzed that H-rich free radicals like H or CH3 produced from the cleavage of aliphatic hydrocarbon chains of WT or other reactions like cyclization stabilize the free radicals from coal pyrolysis and contribute to the improved tar quality and the synergy during co-pyrolysis.

Functional characterization reveals a diverse array of metazoan fatty acid biosynthesis genes.

Long-chain (≥C20 ) polyunsaturated fatty acids (LC-PUFAs) are physiologically important fatty acids for most animals, including humans. Although most LC-PUFA production occurs in aquatic primary producers such as microalgae, recent research indicates the ability of certain groups of (mainly marine) invertebrates for endogenous LC-PUFA biosynthesis and/or bioconversion from dietary precursors. The genetic pathways for and mechanisms behind LC-PUFA biosynthesis remain unknown in many invertebrates to date, especially in non-model species. However, the numerous genomic and transcriptomic resources currently available can contribute to our knowledge of the LC-PUFA biosynthetic capabilities of metazoans. Within our previously generated transcriptome of the benthic harpacticoid copepod Platychelipus littoralis, we detected expression of one methyl-end desaturase, one front-end desaturase, and seven elongases, key enzymes responsible for LC-PUFA biosynthesis. To demonstrate their functionality, we characterized eight of them using heterologous expression in yeast. The P. littoralis methyl-end desaturase has Δ15/17/19 desaturation activity, enabling biosynthesis of α-linolenic acid, eicosapentaenoic acid and docosahexaenoic acid (DHA) from 18:2 n-6, 20:4 n-6 and 22:5 n-6, respectively. Its front-end desaturase has Δ4 desaturation activity from 22:5 n-3 to DHA, implying that P. littoralis has multiple pathways to produce this physiologically important fatty acid. All studied P. littoralis elongases possess varying degrees of elongation activity for saturated and unsaturated fatty acids, producing aliphatic hydrocarbon chains with lengths of up to 30 carbons. Our investigation revealed a functionally diverse range of fatty acid biosynthesis genes in copepods, which highlights the need to scrutinize the role that primary consumers could perform in providing essential nutrients to upper trophic levels.

Evolution of Chemical Component and Physical Properties of Datong Long-Flame Coal After Superheated Water Vapor Pyrolysis

ABSTRACT Datong long-flame coal from China was pyrolysis with superheated water vapor at 300°C to 536°C. Chemical and physical changes of long flame coal, including composition, weight loss, pore fracture structure, density, and water absorption were tested, and the qualitative and quantitative relationships among these changes were analyzed. superheated water vapor pyrolysis removes moisture and volatile components from long flame coals and increases the fixed carbon content. After superheated water vapor pyrolysis, the O/C and H/C atomic ratios of long flame coal decreased due to the decomposition of oxygen-containing functional groups and chain aliphatic hydrocarbons. superheated water vapor pyrolysis increased the porosity of long flame coal by material removal and matrix fracture. Material removal occurs throughout the pyrolysis process but matrix fracture occurs only at the initial stage of the conversion of solid organic matter to oil and gas products. The expansion of pore fractures in long flame coal caused a significant decrease in apparent density and an increase in water absorption. Quantitative analysis revealed the forced water absorption of long flame coal was quadratically polynomial with respect to porosity.

Preparation and Performance Characterization of Exploding Foil Initiator Based on ODPA-ODA Polyimide Flyer.

The exploding foil initiator (EFI) system has been extensively used in ignition and detonation sequences and proved to be of high safety and reliability. Polyimide is considered the ideal flyer material for EFI due to its excellent performance, including thermal stability, outstanding mechanical properties, high radiation resistance, and excellent dielectric properties. In this study, we prepared the EFI based on a polyimide (ODPA-ODA) flyer, which is spin-coated and solidified on patterned copper film in situ. The electric explosion test shows that the prepared EFI has good working performance, and the 4000 V working voltage drove the flyer to reach a maximum velocity of 5096 m/s. The polyimide morphology and chemical structure after the electric explosion was observed by microscope, SEM, XPS, and FTIR, which showed that the polyimide flyer underwent thermal deformation and complex chemical reactions during an electric explosion. A large number of polyimide bonds broke to form new carbonyl compounds, and the opening of aromatic rings was accompanied by the formation of aliphatic hydrocarbon chains. The morphology and chemical structure analysis after the electric explosion test will lay a foundation for us to further understand the working principle and evolution process of polyimide (ODPA-ODA) flyer.

The structural and pyrolysis characteristics of vitrinite and inertinite from Shendong coal and the gasification performance of chars

Different coal macerals have different pyrolysis characteristics. The in-depth study of their pyrolysis characteristics is helpful to realize coal graded utilization. The objective of this paper is to get more information on structural and pyrolysis characteristics of vitrinite (SD-VC) and inertinite (SD-IC) from Shendong coal (SD-R). SD-VC and SD-IC were separated from SD-R by the float and sink method, and their structure and morphology were characterized by POM, XRD, FTIR, and 13C-CP/MAS NMR. The pyrolysis characteristics of the coal sample and its separated macerals were investigated by TG-FTIR and FBR, and the structural feature and gasification performance of pyrolysis chars were analyzed using FTIR, XRD, and TG. The results show that SD-VC has been enriched from 61.80 vol% to 91.49 vol%, and SD-IC has been enriched from 37.12 vol% to 83.66 vol%. The order of weight loss of coal samples is SD-VC > SD-R > SD-IC, and the maximum weight loss rate of SD-VC is − 5.36 wt%/°C at the final pyrolysis temperature of 800 °C and heating rate and 10 °C/min. The maximum peak temperature of aromatic hydrocarbons from SD-VC pyrolysis moves to the lower temperature region compared with SD-IC. In addition, more coal tar and less char have been generated from SD-VC pyrolysis, 11.02 wt% and 66.36 wt%, respectively. SD-VC pyrolysis tar contains more straight chain aliphatic hydrocarbons such as C21 alkanes and alkyl side chains. The values of d002, Lc and Nave of SD-VC char are smaller than those of SD-IC char, indicating that the graphitization degree of SD-VC char is lower than that of SD-IC char. The gasification time of SD-VC char is shortened by 2.77 min than that of SD-IC char, and its gasification maximum weight loss rate is − 7.03 wt%/°C at 1200 °C and 10 °C/min.

Programmed Macromolecular Assembly by Dipole-Dipole Interactions with Aggregation-Induced Enhanced Emission in Aqueous Medium.

Self-assembling polymers by bioinspired directional supramolecular interactions currently hold great scientific and technological interests. Herein, we report an unorthodox strategy based on a dipole-dipole interaction-mediated extended antiparallel dipolar assembly of a model merocyanine (MC) dye for maneuvering the self-assembly of a highly water-soluble MC-functionalized block copolymer (P2). Unlike traditional amphiphilic block copolymers featuring distinct hydrophobic segments (flexible aliphatic hydrocarbon chains or rigid nonpolar aromatic scaffolds), P2 comprises polyethylene glycol monomethyl ether (PEG) as a hydrophilic block and an unconventional structure-directing acrylate block functionalized with polar MC-dyes in the side chains of every repeat unit. In the absence of any additional hydrophobic assistance, P2 spontaneously self-assembles in water through the continuous opposite alignment of its pendant MCs by multiple dipole-dipole interactions to cancel out their ground state dipole moments, which initially generates an H-aggregated species with ill-defined morphology (Aggregate 1). Upon thermal annealing, Aggregate 1 reorganizes into higher-order core-shell nanodisc-like structures (Aggregate 2) driven by the orthogonal π-stacking interactions of the rigid aromatic framework derived from the extended cofacial MC-stacks. The aromatic interiors of the nanodiscs gain colloidal stability from the externally decorated hydrophilic PEG chains. While the initially formed Aggregate 1, predominantly by dipole-dipole interactions, showed remarkable thermal stability due to the cooperative effect of the polymer chain, the hierarchical assembly guided by relatively weaker dispersion forces of the MC-stacked π-surfaces could be tailored by dilution or thermal treatment. Such organized packing of pendant MCs by the dual effect of dipole-dipole interactions and π-stacking conferred several exciting properties to the P2 assembly in water. Long-range ordered antiparallel stacking of the pendant MCs rendered outstanding aggregation-induced enhanced emission (AIEE) properties to the resultant nanostructures in water with increased fluorescence lifetime, quantum yield, and Stokes shift compared to nonaggregating P2 in CHCl3. The remarkable thermal and kinetic stability of the nanodiscs, their guest loading ability, and very low critical aggregation concentration (CAC) were demonstrated by Förster resonance energy transfer (FRET) studies with an encapsulated donor-acceptor dye pair.

An efficient way to synthesize biomass-based molybdenum carbide catalyst via pyrolysis carbonization and its application for lignin catalytic pyrolysis

In this study, a simple and rapid method was proposed to synthesize orthorhombic α-Mo2C as catalyst for lignin catalytic pyrolysis. Biomass in-situ pyrolysis products were used as the carbon source and supporter, the carbonization of Mo precursor was realized under rapid heating. Experimental results show that Pine-Mo2C catalyst can achieve lignin pyrolysis vapor bond breaking and deoxidation under normal pressure, and the yield of monocyclic aromatic hydrocarbons is 13.26 wt%, of which aromatic hydrocarbons with side chain account for 74%. The side chain aliphatic hydrocarbons of lignin are effectively retained, and hydrogen consumption is minimized. The characterization of catalyst and experiments of guaiacol, 2-phenoxy-1-phenylethanol and 4,4′-biphenol shows that efficient deoxidation is due to targeted attack of catalyst on C-O. Therefore, Pine-Mo2C shows excellent activity in promoting direct bond breaking deoxidation of lignin.

Reactive molecular dynamics simulations of soot formation in acetylene combustion with hydrogen addition

Soot emission from combustion devices not only reduces energy efficiency but also poses a serious risk to global warming and human health. The reactive molecular dynamics simulation is used to study the soot formation process of acetylene as the initial fuel and oxygen as the oxidant, and the chemical effect of hydrogen addition on the soot formation of acetylene combustion is deeply analyzed in this paper. The study found that: in addition to the hydrogen abstraction acetylene addition mechanism, it is also an important path that the long carbon chain aliphatic hydrocarbon with branched chain form polycyclic aromatic hydrocarbons by condensation after continuous dehydrogenation; the chemical effect of hydrogen addition linearly reduces the number of carbon in soot particles, the bond angle energy and torsion angle energy of soot, resulting in a smaller soot particle size and a sparse soot morphology. The shape of the soot gradually changes from a dense spindle-shaped structure to a sparse planar structure; the main chemical effect of hydrogen doping inhibits the dehydrogenation reaction of aliphatic hydrocarbons and aromatic hydrocarbons mainly through H + CaHb↔CaHb−1 + H2, thereby inhibiting the formation of polycyclic aromatic hydrocarbons and soot nucleation, ultimately leading to a reduction in soot production.

Compound effects of water immersion and pyritic sulfur on the microstructure and spontaneous combustion of non-caking coal

In order to reveal the compound effects of water immersion and pyrite on the microstructure and spontaneous combustion characteristics of non-caking coal, three coal samples from two neighboring mines were selected and prepared. The SEM observation, CO2 and N2 adsorption, XRD, XRF, FTIR tests and low temperature oxidation experiment were carried out on raw coal and soaked coal (S30). Showing that a large number of pores and fissures developed after waterlogging, especially M2 sample, the oxidation of its pyrite content (FeS2) leads to the promotion of pore development in coal matrix. Simultaneously, the presence of pyrite was more favorable for the generation of various functional groups and the maintenance of long chain aliphatic hydrocarbons during soaking. In conclusion, the presence of pyrite contributes to the micro-physical and chemical changes in the coal body during the water immersion, which further promotes the propensity for spontaneous combustion (combining data on oxygen consumption, gas products and CPT changes) of soaked coal.

Cytostatic and Cytotoxic Effects of Hollow-Shell Mesoporous Silica Nanoparticles Containing Magnetic Iron Oxide.

Among the different types of nanoparticles used in biomedical applications, Fe nanoparticles and mesoporous siliceous materials have been extensively investigated because of their possible theranostic applications. Here, we present hollow-shell mesoporous silica nanoparticles that encapsulate iron oxide and that are prepared using a drug-structure-directing agent concept (DSDA), composed of the model drug tryptophan modified by carbon aliphatic hydrocarbon chains. The modified tryptophan can behave as an organic template that allows directing the hollow-shell mesoporous silica framework, as a result of its micellisation and subsequent assembly of the silica around it. The one-pot synthesis procedure facilitates the incorporation of hydrophobically stabilised iron oxide nanoparticles into the hollow internal silica cavities, with the model drug tryptophan in the shell pores, thus enabling the incorporation of different functionalities into the all-in-one nanoparticles named mesoporous silica nanoparticles containing magnetic iron oxide (Fe3O4@MSNs). Additionally, the drug loading capability and the release of tryptophan from the silica nanoparticles were examined, as well as the cytostaticity and cytotoxicity of the Fe3O4@MSNs in different colon cancer cell lines. The results indicate that Fe3O4@MSNs have great potential for drug loading and drug delivery into specific target cells, thereby overcoming the limitations associated with conventional drug formulations, which are unable to selectively reach the sites of interest.

Vaterite in a decrepitated diamond-bearing inclusion in zircon from a stromatic migmatite in the Chinese Sulu ultrahigh-pressure metamorphic belt

Abstract Vaterite was identified in a decrepitated carbonaceous material (CM) bearing inclusion in zircon from a stromatic migmatite in the Chinese Sulu ultrahigh-pressure (UHP) metamorphic terrane. It is associated with nanometer to micrometer anhedral diamonds, aragonite, calcite, amorphous C-Si-O, and amorphous Zr-Si-O materials. The inclusion developed offshoots and abundant indigenous holes. The C-Si-O material is carbon-rich and porous and shows diagnostic Raman bands of highly disordered CM, whereas the Zr-Si-O material is spherulitic or banded with little or no carbon. The observations from focused ion beam–scanning electron microscope (FIB-SEM) and transmission electron microscope (TEM) verify that both diamond and highly disordered CM are of indigenous origin. The formation pathway of vaterite means that an amorphous calcium carbonate (ACC) phase occurred as the precursor of vaterite. The highly disordered CM contains the subsidiary bands at 1150 and 1250 cm−1 on the low-frequency side of the D1 band, suggesting that there exist aliphatic hydrocarbon chains. Thus, the highly disordered CM was derived from carbonization of some kind of organic species in the fluid inclusion. Decrepitation of inclusion resulted in an extremely high supersaturation state of the fluid that induced the precipitation of amorphous materials and released residual fluid out of the inclusion, which became dry and preserved vaterite and amorphous materials.

Evaluation of anti-biofilm potential of biosurfactant extracted from Nocardia species.

Bacterial natural products such as biosurfactants and surface-active agents are important compounds which exhibit many applications in the fields of medicine. The aim of the present study was to isolate and identify Nocardia strains with high biosurfactant production and antibiofilm ability. In the present study, a biosurfactant producing Nocardia species was isolated and identified by a laboratory method. Nocardia species were initially screened and then tested for their ability to produce biosurfactant. The oil spreading test and the surface tension measurements showed that one strain was a biosurfactant producer. The strain with the best surface activity results was selected for further studies and identified by 16S rRNA gene sequencing method. Fourier transform infrared spectroscopy (FTIR) and compositional analysis proved a biosurfactant structure. Oil spreading test and blue agar plate test confirmed biosurfactants and extracellular anionic glycolipids. E24% assay using olive oil revealed strong emulsifying characteristic of the extracted biosurfactant with 100% emulsifying strength. FTIR spectrum indicated the presence of aliphatic hydrocarbon chain (lipid) along with the polysaccharide portion, confirming the glycolipid nature of the biosurfactant. The stability of the biosurfactant produced in different conditions was significant. Increasing concentration of BS significantly inhibited Pseudomonas aeruginosa biofilm. N. coubleae can be a representative of the genus Nocardia for the production of biosurfactants with beneficial physicochemical properties.