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101.
This paper examines the effects of timber harvesting by skidding on some soil properties (sand, silt, clay, pH, organic carbon, bulk density and compaction), herbaceous cover (unit mass) and forest floor (unit weight) properties. Also N (%), P, K, Na, Ca, Mg, Fe, Zn, Cu and Mn (ppm) were determined in all herbaceous cover, forest floor and two soil depth (0–5 cm and 5–10 cm) on skidroad of an oak (Quercus petrea L.) stand in Istanbul Belgrad Forest – Turkey. In this study, obtained results are; the forest floor and the herbaceous cover amount on the skidroad have been found considerably lower than undisturbed area. There were some crucial changes in the characteristics of the soil which has been investigated down to 10 cm depth. Soil bulk density was found quite high in the samples taken from the skidroad subject to compaction compared to the ones on the undisturbed area. Nevertheless, no important difference had been detected between the skidroad and the undisturbed area at both soil depths in terms of organic carbon contents. Moreover, the soil acidity (pH) values showed noteworthy differences in the analysis of soil samples taken from both soil depths on the skidroad and on the undisturbed area. Fe and Cu contents of herbaceous samples on skidroad were significantly higher than undisturbed area. Forest floor on skidroad had significantly higher K content, and significantly lower Zn, Mn and N content compared to undisturbed area. P, Fe, Zn and Mn contents were found significantly lower in 0–5 cm soil depth on skidroad than undisturbed area. In 5–10 cm soil depth, concentrations of N, P, Fe, Zn and Mn were significantly lower, while Mg and Cu contents were significantly higher than undisturbed area. Results indicate that long-term harvest using skidding techniques on these sites had adversely affected soil cation concentrations, physical soil conditions and mass of herbaceous cover and forest floor.  相似文献   
102.
Centri-voltammetry is a method that combines centrifugation and voltammetry. This method, developed by our group in 2003, yielded promising results when applied to trace analysis of metal ios. We demonstrate here the first application of centri-voltammetry to biosensing systems. A xanthine biosensor was constructed by immobilizing xanthine oxidase on a planar platinum electrode which then was placed at the bottom of a centri-voltammetric cell. The experimental parameters were optimized to give two linear ranges. The first is from 0.1 to 1???M, and the second from 5 to 50???M. The RSD is 3.4 (n?=?5). The biosensor was applied to the determination of xanthine in wine and in urine. Calculated recoveries are 101?±?0.61% (n?=?3) for wine samples, and 102?±?0.556% (n?=?3) for urine samples.
Figure
Centri-voltammetry is a method, which combines the advantages of centrifugation and voltammetry. In this work, the performance of biocentri-voltammetry for xanthine detection has been investigated. After the optimization studies and examination of analytical characteristics, developed centri-voltammetric biosensor was applied for xanthine detection in wine and in urine samples.  相似文献   
103.
This work presents the synthesis and characterization of a novel compound, 4-(thiophene-3-ylmethoxy)phthalonitrile (TMP). The spectroscopic properties of the compound were examined by FT-IR, FT-Raman, NMR, and UV techniques. FT-IR and FT-Raman spectra in solid state were observed in the region 4000–400 cm−1 and 3500–50 cm−1, respectively. The 1H and 13C NMR spectra were recorded in CDCl3 solution. The UV absorption spectrum of the compound that dissolved in THF was recorded in the range of 200–800 nm. The structural and spectroscopic data of the molecule in the ground state were calculated using density functional theory (DFT) employing B3LYP exchange correlation and the 6-311++G(d,p) basis set. The vibrational wavenumbers were calculated and scaled values were compared with experimental FT-IR and FT-Raman spectra. The complete assignments were performed on the basis of the experimental results and total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method. Isotropic chemical shifts (13C NMR and 1H NMR) were calculated using the gauge-invariant atomic orbital (GIAO) method. A study on the electronic properties, such as HOMO and LUMO energies, were performed by time-dependent DFT (TD-DFT) approach. The HOMO and LUMO analyses have been used to elucidate information regarding charge transfer within the molecule. Comparison of the calculated frequencies, NMR chemical shifts, absorption wavelengths with the experimental values revealed that DFT method produces good results.  相似文献   
104.
We prove that the order continuous bidual of an Archimedean r-algebra is a Dedekind complete r-algebra with respect to the Arens multiplications.  相似文献   
105.
The aim of this paper is to study on the Genocchi polynomials of higher order on P, the algebra of polynomials in the single variable x over the field C of characteristic zero and P, the vector spaces of all linear functional on P. By using the action of a linear functional L on a polynomial p(x) Sheffer sequences and Appell sequences, we obtain some fundamental properties of the Genocchi polynomials. Furthermore, we give relations between, the first and second kind Stirling numbers, Euler polynomials of higher order and Genocchi polynomials of higher order.  相似文献   
106.
A selective extraction technique based on the combination of membrane assisted solvent extraction and molecularly imprinted solid phase extraction for triazine herbicides in food samples was developed. Simazine, atrazine, prometon, terbumeton, terbuthylazine and prometryn were extracted from aqueous food samples into a hydrophobic polypropylene membrane bag containing 1000μL of toluene as the acceptor phase along with 100mg of MIP particles. In the acceptor phase, the compounds were re-extracted onto MIP particles. The extraction technique was optimised for the type of organic acceptor solvent, amount of molecularly imprinted polymers particles in the organic acceptor phase, extraction time and addition of salt. Toluene as the acceptor phase was found to give higher triazine binding onto MIP particles compared to hexane and cyclohexane. Extraction time of 120min and 100mg of MIP were found to be optimum parameters. Addition of salt increased the extraction efficiency for more polar triazines. The selectivity of the technique was demonstrated by extracting spiked cow pea and corn extracts where clean chromatograms were obtained compared to only membrane assisted solvent extraction or only molecularly imprinted solid phase extraction. The study revealed that this combination may be a simple way of selectively extracting compounds in complex samples.  相似文献   
107.
Journal of Thermal Analysis and Calorimetry - Aminosilane-modified MCM-41 and SBA-15 mesoporous silicas were synthesized using sodium silicate extracted from gold mine tailings slurry in this...  相似文献   
108.
Sargin  Idris  Karakurt  Serdar  Alkan  Sinan  Arslan  Gulsin 《Journal of fluorescence》2021,31(5):1461-1473

In the study, fluorescent imaging of live cells was performed using fluorescent carbon quantum dots derived from edible mushrooms species; Agaricus bisporus, Pleurotus ostreatus, and Suillus luteus as a fluorophore agent. Carbon quantum dots were synthesized through a facile and low-cost method based on microwave irradiation of dried mushroom samples in hydrogen peroxide solution under optimized conditions (microwave energy, solution type, duration of microwave treatment, amount of mushroom). Upon purification with centrifugation, microfiltration, and dialysis, the lyophilized carbon quantum dots were identified through UV–visible, fluorescence and FT-IR, X-ray photoelectron spectroscopy, X-ray diffraction, high-resolution transmission electron microscopy, and quantum yield calculation. Cell viability assessment of the carbon quantum dots was evaluated against human epithelial cell line PNT1A using the Alamar Blue Assay. In vitro fluorescence cell imaging studies demonstrated that the carbon dots could dynamically penetrate the cell membrane and nuclear membrane and localize in both the cytoplasm and the nucleus.

  相似文献   
109.
In the neutral title complex, trans‐bis(2,2′‐imino­di­ethanol‐N,O)­bis­(iso­thio­cyanato)­nickel(II), [Ni(NCS)2(C4H11NO2)2], the iso­thio­cyanate ions and the di­ethanol­amine mol­ecules act as mono­dentate and bi­dentate ligands, respectively. The NiII ion exhibits a distorted octahedral configuration with crystallographically imposed inversion symmetry and NNCS—Ni—Namine and NNCS—Ni—Oamine bond angles of 88.78 (10) and 89.44 (10)°, respectively. The Ni—N bond distances are in the range 2.069 (3)–2.096 (2) Å. The mol­ecules are linked by hydrogen bonds to form a three‐dimensional infinite lattice.  相似文献   
110.
The aim of this study was to evaluate 99mTc labeled human β-defensin-1 (HBD-1) for discrimination between bacterial infection and sterile inflammation. For this purpose, HBD-1 was radiolabeled with 99mTc and its in vivo distribution was evaluated in inflamed rats with Staphylococcus aureus (S. aureus) and sterile inflamed rats with turpentine oil. After injection into inflamed and sterile inflamed rats, 99mTc-HBD-1 was rapidly removed from the circulation via the kidneys. Binding of 99mTc-HBD-1 to inflamed muscle (T/NT = 20 at 120 min) was two times higher than binding to sterile inflamed muscle (T/NT = 10 at 120 min) of rats. It was demonstrated that 99mTc-HBD-1 can be used to detect S. aureus inflammation in rats. However, the radiolabeled antimicrobial peptide showed only poor uptake in sterile inflammation with turpentine oil in rats. As a result, 99mTc-HBD-1 can be useful for detection of bacterial inflammation.  相似文献   
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