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841.
The removal of tartrazine from aqueous solutions onto the strongly basic polystyrene anion exchangers of type 1 (Amberlite IRA-900) and type 2 (Amberlite IRA-910) was investigated. The experimental data obtained at 100, 200, 300 and 500 mg/dm(3) initial concentrations at 20 degrees C were applied to the pseudo-first order, pseudo-second order and Weber-Morris kinetic models. The calculated sorption capacities (q(e,cal)) and the rate constant of the first order adsorption (k(1)) were determined. The pseudo-second order kinetic constants (k(2)) and capacities were calculated from the plots of t/q(t) vs. t, 1/q(t) vs. 1/t, 1/t vs. 1/q(t) and q(t)/t vs. q(t) for type 1, type 2, type 3 and type 4 of the pseudo-second order expression, respectively. The influence of phase contact time, solution pH and temperature on tartrazine removal was also discussed. The FTIR spectra of pure anion exchangers and those loaded with tartrazine were recorded, too. 相似文献
842.
Monika M. Prange Wolfgang H. Riepe 《Chemical Engineering and Processing: Process Intensification》1987,22(4):183-191
Phase equilibria were studied of a multicomponent model mixture representing the middle distillate of a coal liquefaction product in the gases carbon dioxide and trifluoromethane at temperatures (308–338 K) and pressures (6–30 MPa) above the critical points of the gases. Partition coefficients and separation factors were determined for the individual mixture components by analysing samples from the coexisting phases. The results show that selectivity due to structural properties (π-bonds, dipole moments, etc.) is superimposed by selectivity due to differences in vapor pressures. The concepts of structure selectivity and vapor pressure selectivity are introduced and changes of these parameters with pressure and temperature are reported. Enhancement factors in the carbon dioxide/model mixture system were calculated and show good agreement with the experimental results. 相似文献
843.
Hyunjung Shin Monika Agarwal Mark R. De Guire Arthur H. Heuer 《Journal of the American Ceramic Society》1996,79(7):1975-1978
Thin films of crystalline TiO2 were deposited on self-assembled organic monolayers from aqueous TiCl4 solutions at 80°C; partially crystalline ZrO2 films were deposited on top of the TiO2 layers from Zr(SO4 )2 solutions at 70°C. In the absence of a ZrO2 film, the TiO2 films had the anatase structure and underwent grain coarsening on annealing at temperatures up to 800°C; in the absence of a TiO2 film, the ZrO2 films crystallized to the tetragonal polymorph at 500°C. However, the TiO2 and ZrO2 bilayers underwent solid-state diffusive amorphization at 500°C, and ZrTiO4 crystallization could be observed only at temperatures of 550°C or higher. This result implies that metastable amorphous ZrTiO4 is energetically favorable compared to two-phase mixtures of crystalline TiO2 and ZrO2 , but that crystallization of ZrTiO4 involves a high activation barrier. 相似文献
844.
Jan L. Balaam Darren Grover Monika Jürgens Andy J. Smith Richard Williams 《The Science of the total environment》2010,408(20):4826-1033
Effluent discharges at Rodbourne sewage treatment works (STWs) were assessed using chemical and in vitro biological analysis as well as modelling predictions. Results showed that Rodbourne STW discharged less estrone (E1) than expected, but similar 17β-estradiol (E2) and 17α-ethinyl estradiol (EE2) to those predicted by a widely cited effluent prediction model. The Exposure Analysis Modelling System (EXAMS) model was set up using measured effluent concentrations as its starting point to predict estrogen concentrations along a 10 km length of the receiving water of the River Ray. The model adequately simulated estrogen concentrations along the river when compared to July 2007 measured data. The model predicted combined estrogen equivalents in reasonable agreement with estrogenicity as measured by passive sampler (POCIS) extracts using the yeast estrogen screen. Using gauged mean flow values for 2007 the model indicated that the most important determinand for estrogen exposure in the Ray was not season, but proximity to the Rodbourne effluent. Thus, fish in the first 3 km downstream of Rodbourne were typically exposed to two or even three times more estrogens than those living 7-10 km further downstream. The modelling indicated that, assuming the effluent estrogen concentrations measured in February 2008 were typical, throughout the year the whole length of the Ray downstream of Rodbourne would be estrogenic, i.e. exceeding the 1 ng/L E2 equivalent threshold for endocrine disruption. 相似文献
845.
Modeling the contribution of point sources and non-point sources to Thachin River water pollution 总被引:5,自引:0,他引:5
Major rivers in developing and emerging countries suffer increasingly of severe degradation of water quality. The current study uses a mathematical Material Flow Analysis (MMFA) as a complementary approach to address the degradation of river water quality due to nutrient pollution in the Thachin River Basin in Central Thailand. This paper gives an overview of the origins and flow paths of the various point- and non-point pollution sources in the Thachin River Basin (in terms of nitrogen and phosphorus) and quantifies their relative importance within the system. The key parameters influencing the main nutrient flows are determined and possible mitigation measures discussed.The results show that aquaculture (as a point source) and rice farming (as a non-point source) are the key nutrient sources in the Thachin River Basin. Other point sources such as pig farms, households and industries, which were previously cited as the most relevant pollution sources in terms of organic pollution, play less significant roles in comparison. This order of importance shifts when considering the model results for the provincial level. Crosschecks with secondary data and field studies confirm the plausibility of our simulations. Specific nutrient loads for the pollution sources are derived; these can be used for a first broad quantification of nutrient pollution in comparable river basins. Based on an identification of the sensitive model parameters, possible mitigation scenarios are determined and their potential to reduce the nutrient load evaluated.A comparison of simulated nutrient loads with measured nutrient concentrations shows that nutrient retention in the river system may be significant. Sedimentation in the slow flowing surface water network as well as nitrogen emission to the air from the warm oxygen deficient waters are certainly partly responsible, but also wetlands along the river banks could play an important role as nutrient sinks. 相似文献
846.
Klaudyna Krause Agnieszka Pyrczak-Felczykowska Monika Karczewska Magdalena Narajczyk Anna Herman-Antosiewicz Agnieszka Szalewska-Paasz Dariusz Nowicki 《International journal of molecular sciences》2021,22(19)
Vibrio cholerae represents a constant threat to public health, causing widespread infections, especially in developing countries with a significant number of fatalities and serious complications every year. The standard treatment by oral rehydration does not eliminate the source of infection, while increasing antibiotic resistance among pathogenic V. cholerae strains makes the therapy difficult. Thus, we assessed the antibacterial potential of plant-derived phytoncides, isothiocyanates (ITC), against V. cholerae O365 strain. Sulforaphane (SFN) and 2-phenethyl isothiocyanate (PEITC) ability to inhibit bacterial growth was assessed. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values indicate that these compounds possess antibacterial activity and are also effective against cells growing in a biofilm. Tested ITC caused accumulation of stringent response alarmone, ppGpp, which indicates induction of the global stress response. It was accompanied by bacterial cytoplasm shrinkage, the inhibition of the DNA, and RNA synthesis as well as downregulation of the expression of virulence factors. Most importantly, ITC reduced the toxicity of V. cholerae in the in vitro assays (against Vero and HeLa cells) and in vivo, using Galleria mellonella larvae as an infection model. In conclusion, our data indicate that ITCs might be considered promising antibacterial agents in V. cholerae infections. 相似文献
847.
Katarzyna Bujak Przemyslaw Decewicz Joanna M. Rosinska Monika Radlinska 《International journal of molecular sciences》2021,22(20)
Shewanella is a ubiquitous bacterial genus of aquatic ecosystems, and its bacteriophages are also isolated from aquatic environments (oceans, lakes, ice, and wastewater). In this study, the isolation and characterization of a novel virulent Shewanella phage vB_SspS_KASIA and the identification of three prophages of its host, Shewanella sp. M16, including a mitomycin-inducible Mu-like siphovirus, vB_SspS_MuM16-1, became the starting point for comparative analyses of phages infecting Shewanella spp. and the determination of their position among the known bacterial viruses. A similarity networking analysis revealed the high diversity of Shewanella phages in general, with vB_SspS_KASIA clustering exclusively with Colwellia phage 9A, with which it forms a single viral cluster composed of two separate viral subclusters. Furthermore, vB_SspS_MuM16-1 presented itself as being significantly different from the phages deposited in public databases, expanding the diversity of the known Mu-like phages and giving potential molecular markers for the identification of Mu-like prophages in bacterial genomes. Moreover, the functional analysis performed for vB_SspS_KASIA suggested that, despite the KASIA host, the M16 strain grows better in a rich medium and at 30 °C the phage replication cycle seems to be optimal in restrictive culture conditions mimicking their natural environment, the Zloty Stok gold and arsenic mine. 相似文献
848.
Jacek Baj Alicja Forma Elbieta Sitarz Kaja Karakua Wojciech Flieger Monika Sitarz Cezary Grochowski Ryszard Maciejewski Hanna Karakula-Juchnowicz 《International journal of molecular sciences》2020,21(24)
The alterations in serum trace element levels are common phenomena observed in patients with different psychiatric conditions such as schizophrenia, autism spectrum disorder, or major depressive disorder. The fluctuations in the trace element concentrations might act as potential diagnostic and prognostic biomarkers of many psychiatric and neurological disorders. This paper aimed to assess the alterations in serum trace element concentrations in patients with a diagnosed schizophrenia. The authors made a systematic review, extracting papers from the PubMed, Web of Science, and Scopus databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Among 5009 articles identified through database searching, 59 of them were assessed for eligibility. Ultimately, 33 articles were included in the qualitative synthesis. This review includes the analysis of serum levels of the following trace elements: iron, nickel, molybdenum, phosphorus, lead, chromium, antimony, uranium, magnesium, aluminum, zinc, copper, selenium, calcium, and manganese. Currently, there is no consistency regarding serum trace element levels in schizophrenic patients. Thus, it cannot be considered as a reliable prognostic or diagnostic marker of schizophrenia. However, it can be assumed that altered concentrations of those elements are crucial regarding the onset and exaggeration of either psychotic or negative symptoms or cognitive dysfunctions. 相似文献
849.
Arthur H. Schmidt Michael Petri Monika Fuchs Hannelore Endres Susanne Kortmann 《Advanced Synthesis \u0026amp; Catalysis》1994,336(3):211-217
Oxocarbons and Related Compounds. 20. By Thiophenols Mediated Conversion of Semisquaric Hydrazides to Squaric-1,2-Diamides In the presence of thiophenols semisquaric hydrazides ( 4 ) are converted into squaric-1,2-diamides ( 6 ) upon heating in alcoholic solution. Proof is given that thiosquaric-S-ester-amides ( 8 ) are intermediates in this process. 相似文献
850.
Mateusz Dawidziuk Anna Kutkowska-Kazmierczak Ewelina Bukowska-Olech Marta Jurek Ewa Kalka Dorothy Lys Guilbride Mariusz Ireneusz Furmanek Monika Bekiesinska-Figatowska Jerzy Bal Pawel Gawlinski 《International journal of molecular sciences》2022,23(2)
Actin molecules are fundamental for embryonic structural and functional differentiation; γ-actin is specifically required for the maintenance and function of cytoskeletal structures in the ear, resulting in hearing. Baraitser–Winter Syndrome (B-WS, OMIM #243310, #614583) is a rare, multiple-anomaly genetic disorder caused by mutations in either cytoplasmically expressed actin gene, ACTB (β-actin) or ACTG1 (γ-actin). The resulting actinopathies cause characteristic cerebrofrontofacial and developmental traits, including progressive sensorineural deafness. Both ACTG1-related non-syndromic A20/A26 deafness and B-WS diagnoses are characterized by hypervariable penetrance in phenotype. Here, we identify a 28th patient worldwide carrying a mutated γ-actin ACTG1 allele, with mildly manifested cerebrofrontofacial B-WS traits, hypervariable penetrance of developmental traits and sensorineural hearing loss. This patient also displays brachycephaly and a complete absence of speech faculty, previously unreported for ACTG1-related B-WS or DFNA20/26 deafness, representing phenotypic expansion. The patient’s exome sequence analyses (ES) confirms a de novo ACTG1 variant previously unlinked to the pathology. Additional microarray analysis uncover no further mutational basis for dual molecular diagnosis in our patient. We conclude that γ-actin c.542C > T, p.Ala181Val is a dominant pathogenic variant, associated with mildly manifested facial and cerebral traits typical of B-WS, hypervariable penetrance of developmental traits and sensorineural deafness. We further posit and present argument and evidence suggesting ACTG1-related non-syndromic DFNA20/A26 deafness is a manifestation of undiagnosed ACTG1-related B-WS. 相似文献