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101.
Chemically modified halloysite proved to be an effective adsorbent for the pesticide chlorpropham and 3-chloroaniline from an aqueous solution. Adsorption experiments were conducted using such procedures as the time-dependent (kinetic) procedure and the concentration dependent (isotherm) procedure. Results indicate that the adsorption process is related to the kind of the studied compound. The equilibrium data are well suited to a Freundlich isotherm in the case of both investigated compounds. Adsorption kinetics of chlorpropham and 3-chloroaniline on acid-treated halloysite was successfully described by pseudo-second order kinetic model and the model of Weber and Morris. From the present study, we suggest that the adsorption of chlorpropham and 3-chloroaniline on the modified halloysite is a rather complex process involving two steps: external mass transfer and intra-particle diffusion. 相似文献
102.
Magdalena Rzepka Fatih Özogul Krzysztof Surówka Magdalena Michalczyk 《International Journal of Food Science & Technology》2013,48(6):1318-1326
Quality and safety parameters of Atlantic bonito gravad during 42 days of storage at 7 ± 1 °C were analysed using monitoring sensory quality, microbial contamination, nucleotide degradation products, biogenic amines (BA), trimethylamine (TMA) and thiobarbituric acid reactive substances (TBARS). The shelf‐life of vacuum packed Atlantic bonito gravad was found to be 28 days. Total viable count (TVC) did not exceed 6 log CFU g?1. Malonodialdehyde (MDA) content did not surpass 10 mg kg?1. Nine biogenic amines were detected. Histamine level at the end of the storage was 355.3 mg kg?1. TMA increased from 53.9 to 619.1 mg kg?1. Among indicators based on the products of nucleotide degradation, the H value is best correlated with the sensory assessment. It can be concluded that the storage temperature of bonito gravad must be below 7 °C to prevent the threat to safety and quality posed by biogenic amines, especially histamine. 相似文献
103.
M. Antonia Murcia Magdalena Martínez-Tom M. Carmen Nicols Ana M. Vera 《Food microbiology》2003,20(6):671-679
The stability of the proximate composition (moisture, proteins, lipids and ash) and the microbiological state of cooked ‘ready to eat’ foods in vacuum or modified atmosphere packaging were examined and compared with conventionally packaged (in air) foods. The study was carried out for 7 and 29 days, during which time the food products were stored at 3°C. Vacuum or modified atmosphere packaging were effective for prolonging the shelf-life of the studied products up to 29 days with minimal changes in the proximate composition. Aerobic mesophilic, psychrotrophic microrganisms, and yeasts and moulds increased with time regardless of packaging type but more rapidly under conventional packaging. 相似文献
104.
Food production in four school kitchens was checked in order to improve food safety by establishing a self-regulated control system based on good manufacturing practices (GMPs) and as an introduction to hazard analysis and critical control points (HACCP). A form, which referred to different aspects such as the cleanliness of the installations, personnel hygiene and the prevention of cross-contamination, was used to obtain the necessary data. Furthermore, foods thought to be of high risk were periodically collected for microbiological analysis. Samples for microbiological examination were taken from cutting boards, tables, machines, knives and ingredients (on-line sampling). We used the results as a basis to train foodhandlers to improve the safety of salad preparation, in accordance with GMPs, observing that hygiene improvement depended on chlorine levels in the rinsing water. We also designed several controls for raw materials, cold storage, freezers and available chlorine levels in water. At the end of the study period, we observed a decrease in microbial populations of examined samples, which indicated that the knowledge of hygiene practices on the part of foodhandlers represents a critical control point, as defined by the EC Directive 93/43/EEC on Hygiene of Food Stuffs. 相似文献
105.
Gómez Núñez Jersain García Martínez Magdalena Mompremier Rojacques González Beltrán Beatriz A. Barceló Quintal Icela Dagmar 《Water Resources Management》2022,36(13):5191-5205
Water Resources Management - The behavior of a rainwater harvesting system depends on some variables that cannot be controlled, such as rainfall, building roof size and water consumption. The... 相似文献
106.
107.
In-vessel composting for utilizing of municipal sewage-sludge 总被引:1,自引:0,他引:1
The amount of sludge generated from wastewater treatment plants has been increasing year-by-year as the sewerage service area expanded. The composting process is considered to be one of the best management methods to stabilize different organic wastes. The main goal of this investigation was to find the optimal ratio of the quantity of the organic waste to the quantity of the sewage sludge. The process of composting was carried out in the Horstmann bioreactor (pilot scale) for 2–3 weeks and then in a compost pile for 6–12 weeks. Seven experiments were performed, with different ratios of the quantity of organic wastes to the quantity of sewage sludge. The results enabled an estimation of the quality of compost and its usefulness and also the usefulness of the bioreactor to be deduced. 相似文献
108.
Mario Rothbauer Peter Ertl Barbara A. Theiler Magdalena Schlager Uwe B. Sleytr Seta Küpcü 《Advanced Materials Interfaces》2015,2(1)
The spatial arrangement of cells in their microenvironment is known to significantly influence cellular behavior, thus making the control of cellular organization an important parameter of in vitro co‐culture models. However, recent advances in micropatterning co‐culture methods within biochips do not address the simultaneous cultivation of anchorage‐dependent and non‐adherent cells. To address this methodological gap we combine S‐layer technology with microfluidics to pattern co‐cultures to study the cell‐to‐cell and cell‐to‐surface interactions under physiologically relevant conditions. We exploit the unique self‐assembly properties of SbpA and SbsB S‐layers to create an anisotropic protein nanobiointerface on‐chip with spatially‐defined cytophilic (adhesive) and cytophobic (repulsive) properties. While microfluidics control physical parameters such as shear force and flow velocities, our anisotropic protein nanobiointerface regulates the biological aspects of the co‐culture method including biocompatibility, biostability, and affinity to non‐adherent cells. The reliability and reproducibility of our microfluidic co‐culture strategy based on laminar flow patterned protein nanolayers is envisioned to advance in vitro models for biomedical research. 相似文献
109.
Beata Anna Nowakowska Katarzyna Pankiewicz Urszula Nowacka Magdalena Niemiec Szymon Kozowski Tadeusz Issat 《International journal of molecular sciences》2022,23(1)
Fetal growth restriction (FGR) is one of the most formidable challenges in present-day antenatal care. Pathological fetal growth is a well-known factor of not only in utero demise in the third trimester, but also postnatal morbidity and unfavorable developmental outcomes, including long-term sequalae such as metabolic diseases, diabetic mellitus or hypertension. In this review, the authors present the current state of knowledge about the genetic disturbances responsible for FGR diagnosis, divided into fetal, placental and maternal causes (including preeclampsia), as well as their impact on prenatal diagnostics, with particular attention on chromosomal microarray (CMA) and noninvasive prenatal testing technique (NIPT). 相似文献
110.
Anna Wajler Anna Kozłowska Magdalena Nakielska Kamila Leśniewska‐Matys Agata Sidorowicz Dariusz Podniesiński Piotr Putyra 《Journal of the American Ceramic Society》2014,97(6):1692-1695
Transparent cobalt‐doped magnesium aluminate spinel (Co:MgAl2O4) ceramics with a submicrometer grain size were prepared by spark plasma sintering. For the first time, the nonlinear absorption of Co:MgAl2O4 transparent ceramics was experimentally demonstrated. Both ground state absorption (σGSA) and excited state absorption (σESA) were estimated using the solid‐state slow saturable absorber model based on absorption saturation measurements performed at 1.535 μm. σGSA and σESA for 0.03 at.% Co:MgAl2O4 were found to be 4.1 × 10?19 cm2 and 4.0 × 10?20 cm2, respectively. In the case of 0.06 at.% Co:MgAl2O4 ceramics, σGSA = 2.6 × 10?19 cm2 and σESA= 5.3 × 10?20 cm2 were determined. 相似文献