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21.
This article presents a comprehensive review of the literature on microwave wood testing, offering a critical comparison of
reported methods and techniques. The purpose of this review is to establish current achievements and evaluate the potential
for the application of microwave methods in industry. All reviewed articles are classified based on the way they deal with
four key issues: propagation modeling, measurement technique, hardware implementation, and determination of wood properties.
Currently used methods for propagation modeling are considered first, with particular attention given to the calculation of
propagation factors along the principal directions, because these methods take into consideration wood anisotropy and allow
grain angle detection. Measurement techniques are also considered in more detail, with a qualitative comparison of the two
most advanced techniques: the focused beam technique and the modulated scattering technique. Reported hardware implementation
and methods for determining the wood properties of interest from measured data are reviewed in the final sections. The technology
is mature, but more effort is needed to reach a solution suitable for an industrial environment. This article aims to help
researchers in this field to identify the remaining issues. 相似文献
22.
Mirjana Stojanović Dragi Stevanović Deana Iles Mirko Grubišić Jelena Milojković 《Water, air, and soil pollution》2009,200(1-4):101-108
Uranium is a radiotoxic and chemotoxic heavy metal. Uptake and accumulation of U has been studied in plants native to uranium mine sites, but not in cultivated plants which are commonly consumed by humans. The objective of this study was better understanding of U uptake and accumulation in cultivated plants and whether different contents of uranium (U) in the substrate affect its concentration in plants and their dry matter mass. Two substrate variants for growing plants, which differed in the uranium content: solid wastes (tailings) and tailings mixed with sand (w/w 1:1). Large amounts of solid wastes (tailings) resulting from the exploitation and treatment of uranium ore from the closed uranium mine Gabrovnica–Kalna, on southeast of Serbia, contained generally 15.33 mg U/kg. In the experiment, three plant species (corn NSSC 231, sunflower N.S. Dukat, and green peas Smederevska Palanka) were grown in pots on the four substrate variants during 40 days. Substrate was suffused by drinking water (DW) and “uranium water” (UW), which issue out from the mine, contained 0,053 mg U/ dm3. Obtained results show that when UW was added to tailing concentration of U in plants increased. When the content of U in the substrate was lowered by adding sand, the concentration of U in plants decreased, though was significantly higher in comparison to the variants to which DW was added. Dry matter mass was higher in variants where UW was used. Concentration of U was significantly higher in root than in above-ground parts. 相似文献
23.
Viša Tasić Renata Kovačević Biljana Maluckov Tatjana Apostolovski – Trujić Branislava Matić Mira Cocić Mirjana Šteharnik 《Water, air, and soil pollution》2017,228(6):230
The content of As and heavy metals (Pb, Cd, Ni, and Cu) in total suspended particulate (TSP) and PM10 at 3 locations (Park, Institute, and Jugopetrol) near the copper smelter in Bor (Serbia) has been analyzed within the period 2004 to 2015 with the aim of investigating the seasonal and spatial changes of those pollutants in the suspended particles. The content of As in TSP and PM10 was over the annual EU limit value at all measuring points during the entire period of observation, while contents of Cd and Pb were periodically above the annual EU limits. There were no statistically significant seasonal changes between mean levels of the observed elements in the cold (October–March) and warm (April–September) periods during the year. A strong and moderate positive correlation was detected between the concentrations of each particular element (except Ni) at all measuring points. Additionally, Cd was the most enriched element followed by Pb, As, and Cu, while Ni was low-enriched. The constant air pollution with As particles, sometimes in concentrations even 20 times higher than the permitted annual value, requires urgent undertaking of concrete actions in order to reduce anthropogenic emission of suspended particles in Bor. 相似文献
24.
Andjelkovic M Van Camp J Pedra M Renders K Socaciu C Verhé R 《Journal of agricultural and food chemistry》2008,56(13):5181-5187
The total content of phenolic compounds (TAP) in 29 different monocultivar olive oil samples from France (Aglandau and Tanche) and Spain (Cornicabra, Picual, and Verdial) was assessed by the colorimetric Folin-Ciocalteu method. Also, individual phenolic compounds were determined and quantified by liquid chromatography coupled to mass spectrometry (LC-MS). The French olive oil samples had a lower TAP compared to Spanish samples. The quantity of individual phenolics was similar except for pinoresinol, which was lower in the French olive oil samples. TAP moderately correlated to the sum of quantified compounds (r = 0.64 and p < 0.01) Partial least-squares (PLS) regression analysis emphasized the importance of hydroxytyrosol and the total amount of quantified phenolic compounds by LC-MS in the prediction of the total amount of phenolic compounds as determined by the Folin-Ciocalteu method. The amount of alpha-tocopherol was generally different among the cultivars (Tanche > Picual > Verdial > Aglandau > Cornicabra). Of all quantified phenolic compounds in French olive oil samples, only luteolin correlated well to the altitude of the olive orchards (r = 0.76, p < 0.01). 相似文献
25.
Mihailović Nevena R. Mihailović Vladimir B. Ćirić Andrija R. Srećković Nikola Z. Cvijović Mirjana R. Joksović Ljubinka G. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(3):399-404
Plant Foods for Human Nutrition - A simple and efficient ultrasonic-assisted extraction (UAE) technique was developed in order to find optimal conditions for the extraction of total phenolic... 相似文献
26.
Stocker H Andjelkovic M Oldham S Laffargue M Wymann MP Hemmings BA Hafen E 《Science (New York, N.Y.)》2002,295(5562):2088-2091
The phosphoinositide phosphatase PTEN is mutated in many human cancers. Although the role of PTEN has been studied extensively, the relative contributions of its numerous potential downstream effectors to deregulated growth and tumorigenesis remain uncertain. We provide genetic evidence in Drosophila melanogaster for the paramount importance of the protein kinase Akt [also called protein kinase B (PKB)] in mediating the effects of increased phosphatidylinositol 3,4,5-trisphosphate (PIP3) concentrations that are caused by the loss of PTEN function. A mutation in the pleckstrin homology (PH) domain of Akt that reduces its affinity for PIP3 sufficed to rescue the lethality of flies devoid of PTEN activity. Thus, Akt appears to be the only critical target activated by increased PIP3 concentrations in Drosophila. 相似文献
27.
The essential oil of Achillea clavennae was investigated for its antibacterial activity against some respiratory tract pathogens. Maximum activity was observed against Klebsiella pneumoniae and penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae. The oil also exhibited strong activity against Gram (-) Haemophilus influenzae and Pseudomonas aeruginosa. Gram (+) Streptococcus pyogenes was the most resistant to the oil. 相似文献
28.
Mirjana Stojanović Dragi Stevanović Jelena Milojković Marija L. Mihajlović Zorica Lopičić Tatjana Šoštarić 《Water, air, and soil pollution》2012,223(1):135-144
This work was undertaken to study the influence of soil type and its physical and chemical properties on uranium sorption
and bioavailability, in order to reduce the uncertainty associated with this parameter in risk assessment models and safe
food production. The tests were conducted on three types of Serbian soils: alluvium, chernozem, and gajnjaca, from which 67
samples were taken. Dominant factors of uranium mobilisation: the specific content of total/available form of uranium and
phosphorus, the degree of acidity (pHKCl), and humus content and their correlation, were analysed. Content of available uranium form, according to the type of soil
decreases in the following order: gajnjaca > alluvium > chernozem. It was found the medium correlation between pH values and
available content of uranium in chernozem and gajnjaca, statistically significant at the level of significance of 99% and
the alluvium at the level of significance of 95%. Correlation coefficients in all cases were negative, indicating that the
reduction in pH increases the mobility of uranium and thus its availability for the adoption of the plants. Soil pH was the
only dominant factor that significantly controlled the uranium value with no further significant contribution of other soil
parameters. 相似文献
29.
Mirjana B. ?olovi?Danijela Z. Krsti? Gordana S. Uš?umli?Vesna M. Vasi? 《Pesticide biochemistry and physiology》2011,100(1):16-22
In vitro inhibition of electric eel acetylcholinesterase (AChE) by single and simultaneous exposure to organophosphorus insecticides diazinon and chlorpyrifos, and their transformation products, formed due to photoinduced degradation, was investigated. Increasing concentrations of diazinon, chlorpyrifos and their oxidation products, diazoxon and chlorpyrifos-oxon, inhibited AChE in a concentration-dependent manner. IC50 (20 min) values, obtained from the inhibition curves, were (in mol/l): (5.1 ± 0.3) × 10−8, (4.3 ± 0.2) × 10−6 and (3.0 ± 0.1) × 10−8 for diazoxon, chlorpyrifos and chlorpyrifos-oxon, respectively, while maximal diazinon concentration was lower than its IC50 (20 min). Calculated KI values, in mol/l, of 7.9 × 10−7, 9.6 × 10−6 and 4.3 × 10−7 were obtained for diazoxon, chlorpyrifos and chlorpyrifos-oxon, respectively. However, 2-isopropyl-4-methyl-6-pyrimidinol (IMP) and 3,5,6-trichloro-2-pyridinol, diazinon and chlorpyrifos hydrolysis products, did not noticeably affect the enzyme activity at all investigated concentrations. Additive inhibition effect was achieved for lower concentrations of the inhibitors (diazinon/diazoxon ?1 × 10−4/1 × 10−8 mol/l i.e., chlorpyrifos/chlorpyrifos-oxon ?2 × 10−6/3 × 10−8 mol/l), while an antagonistic effect was obtained for all higher concentrations of the organophosphates. Inhibitory power of 1 × 10−4 mol/l diazinon irradiated samples can be attributed mostly to the formation of diazoxon, while the presence of non-inhibiting photodegradation product IMP did not affect diazinon and diazoxon inhibitory efficiencies. 相似文献
30.
Doolaege EH Raes K Smet K Andjelkovic M Van Poucke C De Smet S Verhé R 《Journal of agricultural and food chemistry》2007,55(18):7283-7287
In this study, two unknown compounds in rosemary oil, containing 3% carnosic acid and 0.3% carnosol, were identified and characterized. After methanol extraction, purification, and analysis by reversed-phase HPLC and LC-MS, a recovery of 92% (+/-8%) of carnosic acid was obtained, but no carnosol was found. However, two unknown compounds with a molecular weight of 330.2 and 302.2 were consistently detected. From additional LC-MS-MS, (1)H NMR, and elemental analyses, it became clear that the first compound (M(w) = 330.2) could not be carnosol. It was hypothesized that it originated from the breakdown of the intramolecular bond of carnosol, followed by the addition of a water molecule. Possibly, an unsaturated double bond was formed after dehydration. Assuming that this compound was an intermediate in the conversion to rosmanol, the second unknown compound (M(w) = 302.2) may have resulted from the breakdown of the intramolecular bond of rosmanol. Similarly, an unsaturated double bond may have been formed. After splitting off carbon oxide, a detectable molecule with a molecular weight of 302.2 was observed. 相似文献