Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Chlorophenols”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,171 records · Page 65Linked to original sources
PubMed2006

Characterization and use of high surface area activated carbons prepared from cane pith for liquid-phase adsorption.

Carbonaceous adsorbents with controllable surface areas were chemically activated with KOH at 780 degrees C from char that had been carbonized from cane pith at 450 degrees C. The pore properties including the BET surface area, pore volume, pore size distribution, and mean pore diameter of these activated carbons were characterized and derived using the t-plot method based on N(2) adsorption isotherms. The activated cane pith carbons, with KOH/char ratios of 2-6, exhibited BET surface areas ranging from 912 to 2299 m(2) g(-1). The scanning electron microscopic (SEM) observations revealed that the surface morphology of honeycombed holes on all activated cane pith carbons was significantly influenced by the KOH/char ratio. The adsorption kinetics and equilibrium isotherms of acid blue 74, methylene blue, basic brown 1, p-nitrophenol, p-chlorophenol, p-cresol, and phenol from water at 30 degrees C on the activated carbons were studied. The adsorption kinetics were suitably described by a simplified kinetic model, the Elovich equation. All adsorption equilibrium isotherms were in agreement with the Langmuir equation, and were used to compare the covered area (S(c)/S(p)) of the activated carbons at different KOH/char ratios. The high-surface-area activated carbons were proven to be promising adsorbents for pollution control and for other applications.

Adsorption↗
PubMed2006

Effect of pentachlorophenol and chemical oxygen demand mass concentrations in influent on operational behaviors of upflow anaerobic sludge blanket (UASB) reactor.

Upflow anaerobic sludge blanket (UASB) reactor that was seeded with anaerobic sludge acclimated to chlorophenols was used to investigate the feasibility of anaerobic biotreatment of synthetic wastewater containing pentachlorophenol (PCP) with additional sucrose as carbon source. Two sets of UASB reactors were operated at one time. But the seeded sludge for the two reactors was different and Reactor I was seeded with the sludge that was acclimated to PCP completely for half a year, and Reactor II was seeded with the mixed sludge that was acclimated for half a year to PCP, 4-CP, 3-CP or 2-CP, respectively. The degradation of PCP and the operation fee treating the wastewater are affected by the concentration of MEDS (microorganism easily degradable substrate). So the confirmation of the suitable ratio of [COD] and [PCP] was the key factor of treating the wastewater containing PCP economically and efficiently. During the experiment, the synthetic wastewater with 180.0 mg L(-1) PCP and 1250-10000 mg L(-1) COD could be treated steadily in the experimental Reactor I. The removal efficiency of PCP was more than 99.5% and the removal efficiency of COD was up to 90%. [PCP] (concentration of PCP) in effluent was less than 0.5 mg L(-1). [PCP] in influent could affect proper [COD] (concentration of COD) range in influent that was required for maintenance of steady running of the experimental reactor with a hydraulic retention time (HRT) from 20 to 22 h. [PCP] in influent would directly affect the necessary [COD] in influent when the UASB reactor ran normally and treated the wastewater containing PCP. When [PCP] was 100.4, 151.6 and 180.8 mg L(-1) in influent, respectively, [COD] in influent had to be controlled about 1250-7500, 2500-5000 and 5000 mg L(-1) to maintain the UASB reactor steady running normally and contemporarily ensure that [COD] and [PCP] in effluent were less than 300 and 0.5 mg L(-1), respectively. With the increase of [PCP] in influent, the range of variation of [COD] in influent endured by the UASB reactor was decreasing. The ratios of [COD] and [PCP] in influent could affect removal efficiency of PCP and COD, the concentration of total volatile fatty acids (VFA) in effluent, biogas quantity and methane content in biogas. [PCP] in influent was linearly or semi-logarithmically correlated to [COD] in effluent when [COD] in influent was 5750+/-250 mg L(-1), and so was the relationship between [COD] in influent and [PCP] in effluent when [PCP] in influent was 100.4 or 151.6 mg L(-1), less than the maximum permissible [PCP]. The sources of seeded sludge, the way of sludge acclimation and the characteristics of anaerobic sludge could all affect the UASB reactor capacity treating PCP. When [PCP] were less than 180.8 mg L(-1) for Reactor I and 151.6 mg L(-1) for Reactor II, the variation of [PCP] in influent had little effect on the UASB reactor volume gas production rate and substrate gas production rate. And [VFA] and pH value in effluent were affected a little. Volume biogas production rate and substrate biogas production rate of the UASB reactor were only affected by [COD] and loading rate in influent. But when [PCP] was more than 151.6 mg L(-1) for Reactor II, the biogas production fell quickly and was over 3 days later. [VFA] in effluent from Reactor II increased up to 2198.1 mg L(-1) quickly and the pH value fell to less than 7. Reactor II could not run normally. The component of VFA accumulated quickly was mainly acetate (above 50%). With [PCP] increased from 7.9 to 180.8 mg L(-1) gradually in influent, the methane content in biogas from Reactor II decreased from 70% to 60%, but the reactor could still run normally. Then as for Reactor II, the content of methane have fallen from 75% to 45% or so quickly. And Reactor II could not run steadily. So the conclusion could be drown that too high [PCP] in influent for UASB reactor mainly inhibited the activity of methane-producing bacteria cultures utilizing the acetate.

Algorithms↗
PubMed2006

Role of the intermediates in the degradation of phenolic compounds by Fenton-like process.

The degradation of three phenolic compounds, 4-chlorophenol, 4-nitrophenol and phenol by Fenton-like process was divided into three phases: the initiation phase, the fast phase and the termination phase. Compared with the initiation phase, the degradation of phenolic compounds, the consumption of H(2)O(2) and the generation of Fe(2+) accelerated dramatically in the fast phase. At the end of the fast phase, about 80% phenolic compounds were removed. After then, the degradation rate slowed down sharply due to the lack of H(2)O(2). The enhancement in the fast phase was caused by the role of some hydroquinone-like intermediates such as hydroquinone, catechol and 4-chlorocatechol, which were identified to reduce Fe(3+) to Fe(2+) quickly. The fast degradation of phenolic compounds promoted the formation of intermediates, thus the concentration of Fe(2+) increased, and vice versa. A reaction pathway describing the role of the hydroquinone-like intermediates was suggested.

Algorithms↗
PubMed2006

Heterogeneous photocatalysed degradation of 4-chlorophenoxyacetic acid in aqueous suspensions.

The photocatalysed degradation of 4-chlorophenoxyacetic acid (4-CPA, 1) has been investigated in aqueous suspensions of titanium dioxide under a variety of conditions. The degradation was studied by monitoring the change in substrate concentration employing UV spectroscopic analysis technique and depletion in total organic carbon (TOC) content as a function of irradiation time. The influence of various parameters such as, different types of titanium dioxide (TiO2) powders, pH, catalyst and substrate concentrations, and in the presence of electron acceptor such as hydrogen peroxide (H(2)O(2)) besides molecular oxygen has been investigated. The effects of these parameters on the degradation rates were found to be significant. The volatile degradation product 4-chlorophenol was analyzed by GC-MS technique and probable pathways for the formation of product has been proposed.

2,4-Dichlorophenoxyacetic Acid↗
PubMed2004

Seasonal and spatial distribution of nonylphenol and IBP in Saemangeum Bay, Korea.

In order to investigate spatial and temporal distribution of organic pollutants in the Saemangeum Bay, organophosphorus pesticides (10), alkylphenols (8), chlorophenols (2), bisphenol A were analyzed from the surface seawater taken in 2002-2003. Most of the analytes were not detected in all stations except nonylphenol and S-benzyl-O,O-di-isopropyl phosphorothioate (IBP). Concentrations of nonylphenol and IBP ranged from ND to 298 ng/l and from ND to 1840 ng/l, respectively. The high levels of nonylphenol and IBP were found in the estuary areas of Mangyeong and Dongjin River. The levels of nonylphenol and IBP in surface seawater varied through seasons and the high levels of nonylphenol and IBP were in summer season (August). Based on real time monitoring of IBP and on correlation between concentrations of target compounds and contents of salinity in seawater, physical mixing and diffusion of seawater were found to be the major factors that affect the spatial distribution of IBP and nonylphenol in the Saemangeum Bay environment.

Environmental Monitoring↗
PubMed2004

Development of degenerate and specific PCR primers for the detection and isolation of known and putative chloroethene reductive dehalogenase genes.

Degenerate and specific PCR primers were designed for the detection of chloroethene reductive dehalogenases (CE-RDase), the key enzymes of chloroethene dehalorespiration, based on sequence information of three CE-RDases and three chlorophenol (CP) RDases. For the design of the degenerate primers, seven conserved amino-acid blocks identified with different bioinformatic tools were used. For one block degenerate, primers containing a 5'-consensus clamp region specific for CE-RDases and a 3'-end degenerate core region specific for RDases in general were designed using the Consensus-Degenerate Hybrid Oligonucleotide Primer (CDHOP) design method. Applying the degenerate primers to genomic DNA of Sulfurospirillum multivorans strain K, Dehalobacter restrictus strain PER-K23, and Desulfitobacterium sp. strain PCE1 led to the isolation of the known CE-RDase genes and three new genes encoding putative reductive dehalogenases that cluster with CE-RDases and not with CP-RDases. In addition, primers designed to be specific for the three known CE-RDase genes, namely pceA of S. multivorans, pceA of D. restrictus, and tceA of Dehalococcoides ethenogenes were successfully tested on genomic DNA of different chloroethene-dehalorespiring bacteria. Nested PCR using degenerate primers followed by a PCR with specific primers allowed a sensitive detection of only 10(2) copies per reaction.

Amino Acid Sequence↗
PubMed2004

Chemical inhibition of PCDD/F formation in incineration processes.

This review summarises results of our pilot-scale experiments to find suitable inhibitors for preventing the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) during waste incineration and to specify the role of the main factors affecting the inhibition process, and is based on doctoral dissertation of Ruokojaärvi (2002). Results of previous experiments reported by other researchers are also presented and compared with ours. The detailed aims of our experiments were (1) to compare the effects of different inhibitors on PCDD/F formation during incineration in a pilot plant, (2) to investigate the role of the particle size distribution of the flue gas on the inhibition of PCDD/Fs, and (3) to find the main parameters affecting PCDD/F inhibition in waste incineration. Prevention of the formation of PCDD/Fs with chemical inhibitors and the effects of different supply points, feed temperatures and process parameters were studied in a pilot scale incinerator (50 kW) using light heating oil and refuse-derived fuel as test fuels. Various concentrations of the gaseous inhibitors (sulfur dioxide, ammonia, dimethylamine and methyl mercaptan) were sprayed into the flue gases after the furnace, in addition to which urea was dissolved in water and injected in at different concentrations. The residence time of the flue gas between the furnace and the PCDD/F sampling point was varied in the tests. In another set of urea tests, urea-water solutions at three concentrations were mixed with the RDF prior to incineration. PCDD/F and chlorophenol concentrations, together with other flue gas parameters (e.g. temperature, O2, CO, CO2 and NO), were analysed in the cooling flue gases. The gaseous and liquid inhibitors both notably reduced PCDD/F concentrations in the flue gas, the reductions achieved with the gaseous inhibitors varying from 50 to 78%, with dimethyl amine the most effective, while that produced with urea was up to 90%. The PCDD/F reductions were greater at increased inhibitor concentrations and with increased residence time of the flue gas between the furnace and the sampling point. PCDD/F concentrations in the particle phase decreased much more markedly than those in the gas phase. The urea inhibitor did not alter the particle size distribution of the PCDD/Fs when the amount of inhibitor was adequate. Chemical inhibitors seem to offer a very promising technique for preventing the formation of PCDD/Fs in waste incineration. The addition of urea to the fuel before combustion proved to be very effective approach and could be a useful technique even in the full-scale incinerators.

Journal Article↗
PubMed2003

Monitoring internal exposure to metals and organic substances in workers at a hazardous waste incinerator after 3 years of operation.

The potential adverse effects of hazardous waste incinerators (HWI) continue to be a subject of worry. The construction of the first and up till now only HWI in Spain finished in 1999. Twenty-six subjects employed at this HWI were divided into three groups: plant, laboratory and administration. Plasma analyses of HCB, PCBs (28, 52, 101, 138, 153 and 180), and PCDD/Fs, as well as urinary analyses of 2,4- and 2,5-dichlorophenol (DCPs), 2,4,5- and 2,4,6-trichlorophenol (TCPs), pentachlorophenol (PCP), and 1-hydroxypyrene (1-HP) were carried out. Blood concentrations of Be, Mn, Hg and Pb, and urinary levels of Cd, Cr, Ni and V were also determined. In plant workers, the current levels of organic substances and metals in blood and urine did not show any increase for any of the compounds analysed (excepting urinary V). By contrast, plasma levels of PCDD/Fs and PCBs 28, 52, 101, 138 and 153 were significantly lower than the respective baseline concentrations. The current chlorophenol concentrations in urine were similar or lower than the baseline levels, with the exception of 2,5-DCP that showed a significant increase. The concentrations of organic and inorganic substances found in this study do not differ from those corresponding to non-occupationally exposed subjects.

Adult↗
PubMed2005

Expression profiling of estrogen-responsive genes in breast cancer cells treated with alkylphenols, chlorinated phenols, parabens, or bis- and benzoylphenols for evaluation of estrogenic activity.

We examined expression profiles of estrogen-responsive genes after treatment with alkylphenols (p-cresol (pC), 4-n-ethylphenol (4EP), 4-n-heptylphenol (4HP), 4-t-octylphenol (4OP) and nonylphenol (NP)), chlorinated phenols (4-chlorophenol (4CP), 4-chloro-3,5-dimethylphenol (CDP), 2,4-dichlorophenol (DCP) and pentachlorophenol (PCP)), parabens (methylparaben (MPB), ethylparaben (EPB) propylparaben (PPB) and butylparaben (BuPB)), or bis- and benzoylphenols (bisphenols A and B and p-hydroxybenzophenone (pHBP)) by means of a DNA microarray assay first to evaluate the estrogenic activity of these chemicals and then to understand the structural basis for the activity. By selecting a set of 120 genes showing greater statistical reliability for estrogen, a more reliable assay for each of the chemicals was achieved and, for the chemicals for which data were available, the results were consistent with those of previously reported estrogen receptor-binding and yeast two-hybrid assays except for chlorinated and few other phenols. Evaluation of the chemicals based on gene function indicated that the genes related to proliferation, transcription and transport were mostly up-regulated while significant numbers of genes related to enzymes and signaling were down-regulated. The genes related to transcription showed the highest degree of variation among the six functional categories (enzymes, signaling, proliferation, transcription, transport and others) for the chemicals with relatively high levels of estrogenic activity. These results indicate that the variations in chemicals and their biological effects can be monitored by the appropriate grouping of estrogen-responsive genes.

Breast Neoplasms↗
PubMed2005

Enhanced electro-catalytic degradation of chloroorganic compounds in the presence of ultrasound.

The application of finely divided (black) Pd and Pd-Fe powder in the sono-electro-catalytic reduction of chlorophenoxy herbicides (2,4-D) and chlorophenols (2,4-DCP) in aqueous solutions allows for effective destruction of toxic chlorinated aromatic compounds. At 20 degrees C complete conversion of these compounds is observed within 10 min. On bimetallic Pd/Fe catalyst, intermediates due to the oxidation reaction are detected in addition to the products of dechlorination. The bimetallic catalyst appears to be energetically and economically superior to the Pd. In both cases, the reaction times were considerably shortened in comparison with traditional electro-catalytic processes.

Catalysis↗
PubMed2006

Ultrasonic destruction of phenol and substituted phenols: a review of current research.

Phenol and some of its derivatives such as chlorophenol and nitrophenol have received considerable attention from environmental scientists and engineers, due to their undesirable effects in the water environment, where they end up as a result of improper disposal methods. As a consequence, research has been conducted all around the world with the common goal of reducing their concentrations to allowable limits or converting them to non-toxic, non-hazardous forms that may easily be handled by natural decay processes. Some of this research has focused on ultrasonic techniques, which currently appears to present a convenient but as yet unproven method for large scale water remediation. The goal of this study is to identify and review some of these studies that are directly related with the use of ultrasound in decontaminating effluents with phenol residuals and to summarize the main points of interest and problems encountered.

Phenols↗
PubMed2005

Application of a neural observer to phenols ozonation in water: simulation and kinetic parameters identification.

Presented in this study, a dynamic neural network (DNN) is employed to estimate the states dynamics of the phenols-ozone-water system. A new technique based on the dynamic neural network observer (DNNO) with relay (signum) term is applied to estimate the decomposition dynamics of phenols and to identify their kinetic parameters without any mathematical model usage. The decomposition of phenols (phenol (PH), 4-chlorophenol (4-CPH) and 2,4-dichlorophenol (2,4-DCPH)) and their mixture by ozone, realized in a semi-batch reactor, is considered as a process with uncertain model ("black-box"). Only one parameter monitoring, namely, the ozone concentration in gas phase in the reactor outlet, is measured during ozonation. The variation of this variable is used to obtain the summary characteristic curve for the phenols ozonation. Then, using the experimental decomposition dynamics of phenols and of their mixture, obtained by HPLC method, the proposed DNNO is applied to estimate the ozonation constants of phenols at the different pH 2-12. A good correspondence between the decomposition dynamics and the estimated ones by DNNO is obtained.

Computer Simulation↗
PubMed2006

Fe(III) homogeneous photocatalysis for the removal of 1,2-dichlorobenzene in aqueous solution by means UV lamp and solar light.

Chlorinated hydrocarbons are widely used in chemical industries as solvents and intermediates for pesticides and dyes manufacture. Their presence was documented in rivers, groundwaters and seawaters. In this work, the oxidation of 1,2-dichlorobenzene in aqueous solutions by means of Fe(III) homogeneous photocatalysis under UV lamp and sunlight irradiations is studied. The results show that the best working conditions are found for pH=3.0 and initial [Fe(III)] concentration equal to 1.0x10(-4) molL(-1) although the investigated system can be utilized even at pH close to 4.0 but with slower abatement kinetics. Some dicholoroderivatives, such as 2,3-dichlorophenol, 3,4-dichlorophenol and 2-chlorophenol, are identified as oxidation intermediates. The values of the kinetic constant for the photochemical reoxidation of Fe(II) to Fe(III) are evaluated by a mathematical model in the range 1.58-3.78 Lmol(-1)s(-1) and 0.69-0.78 Lmol(-1)s(-1) for the systems irradiated by UV lamp and sunlight, respectively.

Catalysis↗
PubMed1998

Purification and characterization of the 3-chloro-4-hydroxy-phenylacetate reductive dehalogenase of Desulfitobacterium hafniense.

The membrane-bound 3-chloro-4-hydroxyphenylacetate (Cl-OHPA) reductive dehalogenase from the chlorophenol-reducing anaerobe Desulfitobacterium hafniense was purified 11.3-fold to apparent homogeneity in the presence of the detergent CHAPS. The purified dehalogenase catalyzed the reductive dechlorination of Cl-OHPA to 4-hydroxyphenylacetate with reduced methyl viologen as the electron donor at a specific activity of 103.2 nkat/mg protein. SDS-PAGE revealed a single protein band with an apparent molecular mass of 46.5 kDa. The enzyme contained 0.68 +/- 0.2 mol corrinoid, 12.0 +/- 0.7 mol iron, and 13.0 +/- 0.7 mol acid-labile sulfur per mol subunit. The N-terminal amino acid sequence of the enzyme was determined and no significant similarity was found to any protein present in the gene bank.

Acetates↗
PubMed2000

Micelle-mediated extraction for concentrating hydrophobic organic compounds.

An extraction method based on polymer-induced phase separation of aqueous micellar solutions of octyl-beta-D-thioglucoside (OTG) was assessed for concentrating hydrophobic analytes. Various hydrophobic compounds such as polycyclicaromatic hydrocarbons, alkylbenzenes, alkylphenols, chlorobenzenes, chlorophenols, phthalic esters, pesticides, and steroid hormones could be efficiently concentrated into a small volume of surfactant-rich phase, while hydrophilic matrix components remained in the bulk aqueous phase. The surfactant-rich phase containing concentrated OTG could be directly introduced into the hygro-organic mobile phase of high-performance liquid chromatography with ultra-violet photometric detection. The application of this method greatly enhanced the signal intensity in the chromatogram while reducing the interference of matrix components.

Chromatography, High Pressure Liquid↗
PubMed2000

Monitoring of priority pesticides and other organic pollutants in river water from portugal by gas chromatography-mass spectrometry and liquid chromatography-atmospheric pressure chemical ionization mass spectrometry.

Gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (LC-APCI-MS) were optimized and applied for the trace-level determination of 42 priority pesticides and 33 priority organic pollutants from European Union Directive EC 76/464. First, off-line solid-phase extraction of 200 ml of river water using an OASIS solid-phase extraction cartridge, followed by GC-MS was used. Next, selected samples that were positive to GC-MS were analyzed by LC-APCI-MS in order to detect further polar byproducts or to improve the determination of previously detected polar analytes. The transformation products of triazine pesticides like deethylatrazine (DEA) and deisopropylatrazine (DIA) and compounds such as diuron and several chlorophenols were positively identified by LC-APCI-MS. The present methodology has also been used for searching for new analytes not included in the EC 76/464 list, like Irgarol, DEA and DIA. In addition it was applied to target pollutants in 43 river water samples from Portugal during a pilot survey from April to July 1999. Atrazine followed by simazine and 2,4,6-trichlorophenol were the most ubiquitous compounds detected in this area. The levels detected of the different compounds were in the range of: 0.01-2.73 microg/l, 0.05-0.74 microg/l, 0.02-1.65 microg/l, 0.02-5.43 microg/l, 0.01-0.40 microg/l, 0.01-0.26 microg/l, 0.02-0.61 microg/l, 0.01-3.90 microg/l, 0.01-1.24 microg/l, 0.02-2.3 microg/l, 0.01-0.13 microg/l and 0.01-0.5 microg/l for atrazine, simazine, terbuthylazine, alachlor, metolachlor, Irgarol, propanil; tributhylphosphate, diuron, 2,4,6-trichlorophenol, deisopropylatrazine and deethylatrazine, respectively.

Atmospheric Pressure↗
PubMed2000

Separation of acidic solutes by nonaqueous capillary electrophoresis in acetonitrile-based media. Combined effects of deprotonation and heteroconjugation.

Nonaqueous capillary electrophoresis (NACE) is a chemical separation technique that has grown in popularity over the past few years. In this report, we focus on the combination of heteroconjugation and deprotonation in the NACE separation of phenols using acetonitrile (ACN) as the buffer solvent. By preparing various dilute buffers consisting of carboxylic acids and tetrabutylammonium hydroxide in ACN, selectivity may be manipulated based on a solute's dissociation constant as well as its ability to form heterogeneous ions with the buffer components. ACN's low viscosity, coupled with its ability to allow for heteroconjugation, often leads to rapid and efficient separations that are not possible in aqueous media. In this report, equations are derived showing the dependence of mobility on various factors, including the pKa of the analyte, the pH and concentration of the buffer, and the analyte-buffer heteroconjugation constant (Kf). The validity of these equations is tested as several nitrophenols are separated at different pH values and concentrations. Using nonlinear regression, the Kf values for the heteroconjugate formation between the nitrophenols and several carboxylate anions are calculated. Also presented in this report are the NACE separations of the 19 chlorophenol congeners and the 11 priority pollutant phenols (used in US Environmental Protection Agency methods 604, 625/1625 and 8270B).

Acetonitriles↗
PubMed2001

In situ derivatisation using pressurized liquid extraction to determine phenols, sterols and carboxylic acids in environmental samples and microbial biomasses.

Pressurized liquid extraction was combined with in-situ derivatisation to extract polar analytes such as phenols (including chlorophenols) sterols and carboxylic acids from environmental and microbial samples. This one-step protocol uses acetic anhydride as an acetylation agent, N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) as an silylation agent, and boron trifluoride-methanol, phenyltrimethyl ammoniumhydroxide and trimethyl sulfoniumhydroxide as methylation agents. It results in faster extraction rates and better or comparable extraction efficiencies when compared to classical approaches. The addition of a silylation agent also facilitates the extraction kinetics of analytes not accessible to silylation (e.g. polycyclic aromatic hydrocarbons or alkylbenzenes). This may be attributed to a dissociative action of the agent to weaken analyte-matrix interactions.

Acetylation↗